Safety Topics Prominently Featured
Dr. Euliano Named 1995 APSF Young Investigator
Editorial: The State of the APSF and of Older Anesthesiologists
Selected Comments on "Aging Anesthesiologists" from Questionnaire Respondents:
Letters to the Editor
APSF Exhibit at ASA Shows Real Gas Pipeline Problems
Safety Danger in Cost Cutting Discussed at ASA
ASA Exhibits Also Showcase Safety Concerns
Two New ASA Safety Videotapes Premiere
APSF Awards 3 Safety Research Grants
Sample Publications Resulting from APSF Grant-Supported Research More Than $1 Million in Grants Awarded in Seven Years
Pierce Award Winners
by Susan K. Palmer, M.D., Douglas C. Guyton, M.D., Robert C. Morell, M.D., and Gerald L. Zeitlin, M.D.
At the annual meeting of the American Society of Anesthesiologists in San Francisco October 15-19, patient safety was again the underlying theme of a significant number of scientific presentations.
For example, a scientific poster session was held Wednesday morning, October 19, during which 29 abstracts were presented regarding patient safety, epidemiology, history and education. Topics included anesthesia simulators, postoperative nausea and vomiting, the safety of sevoflurane, and several outcome indicators related to coronary artery bypass surgery.
Three posters dealt with the use of anesthesia simulators. Members of the Department of Anesthesiology from the University of Copenhagen at Herlev, Denmark, led by Dr. A. Lindekaer, studied the performance of eight anesthesiologists in the simulated scenario of unexpected ventricular fibrillation. Although the principles of ACLS were largely followed, the subjects were inconsistent in their performance and case management.
Dr. D. Gaba and colleagues, from Stanford and the Palo Alto VA Medical Center, examined interrater reliability of performance assessment during simulated episodes of cardiac arrest and malignant hyperthermia. Their results indicate that a single rater had a much greater chance of differing significantly from the mean score of five raters than did the score of a team of two raters. They suggested that evaluation reliability might be improved if:
1. raters are paired; 2. discussion is allowed prior to rating performance; 3. a simplified rating scale is used; and 4. specific performance behaviors are defined.
A survey of anesthesiologists' attitudes toward simulators was conducted by Dr. R. Riley and colleagues from Royal Perth Hospital in Australia and the University of Pittsburgh. This study surveyed 181 Australian and American anesthesiologists. Results revealed that 73% of staff were in favor of departmental purchase of a simulator and 69% were willing to undergo evaluation using a simulator. Only 28% were supportive of compulsory simulator testing for re-certification. Many were concerned with cost.
Dr. T. Grasela and colleagues (part of a multicenter phase IV study and affiliated with SUNY in Buffalo, NY) reported an observational study on the effect of anticholinesterase agents on the incidence of postoperative nausea and vomiting (PONV). This study was conducted at 391 hospitals and included 6,908 patients. The authors found a slight increase in PONV in patients who received either neostigmine or pyridostigmine compared to patients receiving no anticholinesterase. They also noted a significant decrease in PONV in those patients receiving edrophonium. Dr. R. Mirakhur et al. (The Queen's University and the Royal Victoria Hospital in Belfast, Ireland, as well as the University of Oklahoma) presented data which demonstrated the inability of atropine or glycopyrrolate to decrease nausea and vomiting after strabismus surgery, despite their success in inhibiting the oculocardiac reflex. P. Diemunsch and colleagues conducted a multi-center dose ranging study of the ability of granisetron, a 5-HT3 antagonist, to prevent postoperative nausea and vomiting. This study was sponsored by SmithKline Beecham and involved 35 medical centers in Europe and South Africa. Compared to placebo, granisetron was found to be effective at post induction doses of I and 3 mg.
Renal Safety of Sevoflurane
T. Stickler and colleagues (Abbott Labs) described the incidence of inorganic fluoride concentrations > 50 mol/L (considered by many to be the threshold blood level for concern about nonoliguric renal failure) in children and adults who were anesthetized with sevoflurane or reference agents (halothane, isoflurane or enflurane). 1,771 patients were included in the study in which 1,174 patients received sevoflurane and 597 received reference agents. 58 adults (8.1%) of adult patients in the sevoflurane group had inorganic fluoride concentrations @ 50 mol/L. No children nor any patients in the reference groups had inorganic fluoride levels exceeding the 50 mol/L threshold. No cases of renal failure were observed.
CABG and CPK
J. Ramsay from Emory University, working with co-authors from UCSF and The Medical College of Wisconsin, examined the association between Q-wave myocardial infarction (MI) and CPK-MB elevation after elective coronary artery bypass surgery. They found a weak relationship between these two indicators. Depending on the definition of myocardial infarction and the threshold for CPK-MB elevation, the incidence of a diagnosis of postoperative MI could vary from > 20% to < 2%. They believe that this variability could be an important consideration in outcome studies. A. Aggarwai's group (same affiliations) examined the levels of CPK-MB following coronary bypass surgery at 15 medical centers throughout the United States. They presented the incidence of peak serum CPK-MB exceeding different threshold values. Their results indicate that release of this enzyme occurs as a continuum rather than occurring as a threshold phenomenon. These authors believe that this data may also have importance in the interpretation of complication and outcome studies.
Dr. K. Tuman and colleagues from Rush University, UCSF, the University of New Mexico and Harvard University reported on the effect of preoperative 8-blocker and calcium channel blocker therapy on the incidence of myocardial infarction and death after coronary artery bypass surgery. 2,284 patients undergoing CABG procedures at 24 medical centers were included in their database. The authors were not able to identify a beneficial outcome effect of either of these preoperative therapies on the incidence of postoperative MI or death. They speculate that these preoperative medications may not have adequate protective effects during and following the period of cardiopulmonary bypass. This study did not examine the effect of intraoperative or postoperative administration of either 8-blockers or calcium channel blockers.
Cardiac Anesthesia and Monitoring
Researchers at the Cleveland Clinic were able to use a unique cardiac data registry to examine the relationship between post-cardiac surgery arrhythmias and mortality. The registry of information was compiled concurrently during each patient's intensive care unit stay. Data concerning serious arrhythmias in more than 3,000 patients showed that postoperative occurrence of a serious arrhythmia was a marker for higher mortality (15.6%) versus those patients who had no serious arrhythmias (1.7%). Female patients showed a greater incidence of arrhythmias (22.6%) compared to male patients (16.4%) even though other markers of cardiac disease were comparable. Mortality increased in the following order: supraventricular tachycardia, 13.5% mortality; heart block, 16.2%; ventricular tachycardia, 25.5%; and asystole, 74%.
Pediatric anesthesiologists at New England Medical Center in Boston studied the effect of transesophageal echocardiography (TEE) on hemodynamics in small infants undergoing cardiac procedures. They were able to document the disappearance of an arterial waveform in an extremity or the fall of blood pressure or oxygen saturation after placement of the TEE probe in infants weighing less than seven kilograms with cyanotic heart malformations. They recommend monitoring oxygen saturation in all extremities and consideration of removal of TEE probes during cardiopulmonary bypass if oxygen saturation or blood pressure falls in any extremity.
Anesthesiologists at Hahnemann University found that deflation of a thigh tourniquet routinely produces a shower of venous embolism greater than 3 mm in diameter detectable by TEE. Their study of embolic phenomena during two surgical techniques for total knee replacement showed that right ventricular embolism were almost always detected after tourniquet deflation. The period immediately following tourniquet deflation may present special risks for some patients since emboli were also seen in the left ventricle of 3 out of 56 patients studied.
Quality improvement data gathered during all anesthetic cases at the University of Colorado Health Sciences Center were examined to gain information about common problems with spinal and epidural blocks. The most common complication of 2,368 regional blocks performed in a 12-month period was failure of the blocks to anesthetize adequately for the planned surgery, which occurred in 4.8% of spinals and 3.8% of epidurals. Failure of epidural anesthesia occurred slightly more often in the older and sicker general operating room patients (7.7%) than in the obstetric patients (2.6%). Concerning complications, there was only one toxic reaction, two high blocks, and two extended duration blocks. No long term problems were recorded. Knowledge of realistic potential failure rates for major regional blocks can help practitioners and patients plan and prepare for alternate anesthetic methods.
Meta-analysis (statistically combining several similar studies) has become popular because it may demonstrate relationships or significant differences among clinical techniques which individual studies could not confirm. Anesthesiologists at the University of Cincinnati College of Medicine analyzed qualifying studies comparing pencil-point spinal needles with Quinke spinal needles to show that the Quinke-type needles were three times more likely to cause post-dural puncture headaches.
Problems with Intubations and Resuscitation
Difficult intubations are not easy to predict with precision, but patients who present for uvuloplasty are at least 24 times more likely to be impossible to intubate than the general population of operating room patients, according to Dr. B. Shapiro and colleagues at Northwestern University Medical School. The uvuloplasty patients studied were not morbidly obese but were still impossible to intubate in 3.8% of cases and difficult to intubate in 13.5% of cases.
Videotape recordings of intubations and resuscitation were used to analyze errors in technique by Dr. N. Jefferies and colleagues at the University of Maryland. Video was able to record improper cricoid pressure or neck stabilization techniques as well as difficulties with ventilator set-ups. When asked to self report errors during these resuscitations, practitioners tended to report adverse outcomes rather than procedural (process) errors.
At Massachusetts General Hospital, a study of emergency resuscitation found that managing the families of arrested patients and identifying the leader of the code teams were frequent problems. Missing supplies and/or malfunctioning equipment also plagued at least one third of the resuscitations. Although the identified problems were not contributory, a 30% immediate death rate following attempted resuscitation was recorded for these inhospital arrests.
At Dalhousie University, a study was conducted of the efficiency of airway management during in-hospital arrests. The plastic disposable laryngoscopes stocked in code carts were discovered to provide less-than-adequate visualization and even fractured on occasion. The study also found that small endotracheal tubes (6.0 mm or less) were needed and seldom available.
Using a bench set-up to simulate patient tissue resistances, Dr. S. Glowacki of Jefferson Medical College tried to induce current flow in a pulmonary artery (PA) catheter using a standard electrocautery unit. Although measurable current could be induced between the electrodes of the ejection fraction PA catheter, it was not clear that sufficient current could be induced in this manner to be a cause of arrhythmias with the use of these two devices together in the usual operating room setting.
The importance of education and vigilance in patient safety was underscored by a study performed by Drs. R. Leyssius and C. Kalkman from The Netherlands. In the first phase of their study, they determined the incidence, severity and duration of hypoxemic episodes in 450 PACU patients, with the PACU personnel unaware of the data collection. In phase two, they repeated their study with the PACU personnel aware of the data collection, and with an explicit written instruction to prevent desaturation below 90%. Reductions in incidence and severity of desaturation of 25-40% from Phase I to Phase H were reported. Four to six months after the study, data was again collected without the knowledge of PACU personnel (Phase HI). Unfortunately, the results of Phase III showed little difference from Phase 1, indicating that the improvements caused by increased awareness and vigilance during Phase 11 were not long lasting. It was felt to be of interest to see if the improvements occurring in Phase 11 could be sustained during a program of continuous education and increased awareness.
Computerization figured prominently in the 1994 meeting. Frequently cited reasons for reliance on computers included reduced costs (and even increased remuneration!), increased speed of information dissemination, and improved manipulation of data. "The automated record" stood as the goal in many presenters' not-too-distant future.
Reporting from the University of Florida Dr. G. Gibby demonstrated improved capture of comorbidity diagnoses using a computerized pre-op evaluation form. Review of the computerized pre-op form resulted in reporting additional diagnoses in 22/180 records, and altered DRG coding in 5/180. Improved DRG coding results in more accurate epidemiologic data used for reporting purposes and scientific investigation. Dr. Gibby related the improved capture of comorbidity diagnoses not only to the readable, retrievable form that doesn't forget or omit, but also to the anesthesiologist's 'fresh perspective caring for the total patient' that results in a more complete listing of both acute and chronic medical problems. Another benefit was an additional $41,492 (a 1.5% increase) in reimbursement as a result of more accurate coding!
Dr. L. Mark, Johns Hopkins University, reported the development of an "Anesthesiology Consultant Report,' designed to facilitate communication between the anesthesiologist and primary physician. An alternative to patients as the messengers ("Something happened during my surgery, somebody said my heart stopped.'), the report establishes a direct physician-to-physician link, legibly summarizing specific anesthetic concerns and perioperative events that may be of importance to the patient's future health care. The negative aspects of an additional form 'to unravel the mysteries of the anesthetic record' were offset by the high rate of acceptance (82%) among the surgeons and primary we physicians to whom the report was delivered. Personal computers increased the speed and reduced the cost of producing these reports.
Dr. D. Doblar from the University of Alabama at Birmingham developed a scanner-based Continuous Quality Improvement System utilizing a personal computer. Such a system provides the flexibility to create practice-specific CQI indicators with ease. Rapid access to continuously updated CQI data risk adjusted to the specific patient population makes current individual and department profiles immediately available. Other advantages include reduced labor costs for data collection and processing.
Dr. R. Westerlund, New York University, validated the quality assurance process with a report on 65,008 cases from his institution. Consolidating input from QA forms, patient and physician reports, anesthetic records, as well as from 'word of mouth,' Dr. Westerlund utilized the QA process to identify and analyze problems. The QA process focused education in specific areas and appeared to lead to decreases in PACU reintubations, unplanned extubations, pulmonary edema, PACU respiratory depression, and allergic reactions to latex. Cooperative efforts with the pharmacy department led to decreased likelihood of drug misidentification due to look-alike ampules, and joint ventures with the surgery department resulted in better fluid management and blood product utilization.
Examining the reliability of QA data acquisition, investigators at the Massachusetts General Hospital looked specifically at inpatient units' reporting of adverse drug events (ADE) that resulted in patient injury. They determined that reliance on Incident Reports alone was fraught with error, fading to discover 94% of cases of patient injury. Pilot studies showed voluntary submission captured 10% of events, while intensive chart review captured 90%. They suggested computerized ordering to minimize illegibility and transcription errors, facilitation of anonymous reporting of events, and 'self-correcting teams" that find their own solution to problems and report to administrators.
Dr. L. Mark of Johns Hopkins reviewed the first III patients enrolled in the Medic Alert Difficult Airway/intubation Registry. Verifying the Registry's utility, she showed that anticipated difficulty with airway management was associated with significantly fewer intubation techniques (2.3/patient) and fewer adverse events (22%) when compared to unanticipated difficulty (3.7 techniques/patient; 44% adverse events). Interestingly, conventional laryngoscopy was successful in less than 20% of patients with difficult airways, prompting Dr. Mark to suggest that when difficult laryngoscopy/difficult airway is encountered, 'changing technique may be more beneficial than changing blades.' More reports will be forthcoming, as more patients are added to the database and as registered patients reenter the healthcare system for additional treatment.
Follow-up surveys of 61 patients enrolled in the Medic Alert Difficult Airway/Intubation Registry showed 100% satisfaction with the overall process of enrollment, despite a high rate of adverse events (19/61, or 31%) in " group. Each enrollment form includes text specifically designed to address patient concerns and answer the most frequently asked questions. In addition, enrollees are provided with a visible Medic-Alert emblem, a wallet card, and a 24-hour emergency response system including FAX transmission of airway management records. Physicians are urged by the investigators to refer patients to the registry as an important step in relaying vital information to family and health care providers, information that may prevent future disasters.
Dr. D. Mangano from University of California at San Francisco presented preliminary data from the McSPI Research Group demonstrating an association between adverse postoperative outcomes and increased hospital costs. Vascular complications and stroke lengthened hospital stay by 60-70%, and stroke, CHF, and global encephalopathy increased ICU utilization by 40-50%. Stated, but not addressed, was reduction of the incidence of adverse outcomes (and healthcare costs) by improving quality of care. This awaits further study and analysis.
Another study from the McSPI Research Group Institutions examined the utilization of blood products in coronary artery bypass surgery. In a group of patients selected to be at low risk for transfusion there was good agreement among the 23 institutions for transfusion when the hemoglobin level was low; however, marked disparity in use of blood products was evident as the higher hemoglobin values were encountered. The incidences of complications and outcome data were lacking. However, marked differences in risk of complications from blood transfusion as well as inconsistent allocation of limited blood bank resources have obvious patient safety implications. The authors concluded that, despite the issuance of national consensus statements between 1985-88, substantial variability of practice persists, and a more aggressive approach to rational transfusion practice is warranted.
In a retrospective analysis, investigators at the Mayo Clinic estimated the incidence of dental injuries that led to dental consultation and recommendation for intervention/repair. Such injury occurred in 1/3,064 general anesthetics and 1/41,938 local or regional anesthetics with intravenous sedation. In each group injury was most commonly associated with intubation and use of oral airways, respectively, and the cost of repair ranged from $18 to $3,603. Risk factors for injury included general anesthesia with tracheal intubation, preexisting poor dentition, and increased difficulty of intubation. Limited cervical motion was a prominent feature of the patient with a difficult airway. Interestingly, the level of training of anesthesia personnel did not correlate with the incidence of tooth injury.
There were several posters of considerable interest that in past years would not have been thought of as being core patient safety issues; they illustrate the extraordinarily rapid shifts in 'spearhead' issues affecting the practice of anesthesia.
Four posters dealt with various aspects of sterility and prevention of infection. Dr. J. Scharf and colleagues from the University of South Florida examined again the question of whether perioperative blood transfusion, by suppressing the patient's immune function, produced increased rates of post surgical infection. Despite using antibiotics routinely and microaggregate filters in the blood administration equipment, they found significantly more deep wound infections, wound dehiscence and multiple infections in transfused than in nontransfused patients. They point out that there were many confounding factors (e.g. length of operation) but by using logistic regression they found only ASA Classification and transfusion to be reliable predictive factors for infection.
In a thoughtful laboratory study, Dr. P. Langevin and associates placed an external inoculum of staphylococcus Aureus in a Monoject syringe and observed the effects of multiple subsequent injections. One cc of a precisely prepared culture was placed into the barrel of a syringe above the plunger. With each depression of the plunger, they found rapidly increasing numbers of 'colony forming units' in the sterile liquid previously placed below the plunger seal. They therefore recommend that indeed a syringe of this type should not be used more than once in a case.
Dr. M. Brown and colleagues of Wayne State University asked whether the re-use of syringes with a T-port extension (with a back check valve) plugged into the main conduit of a blood-containing IV set is safe. An expired unit of blood was placed in a pressure infuser and maintained at 300 mm Hg. Six 10 [email protected] syringes containing saline were connected at various points along the IV line each via a T-port extension. Samples of this saline were taken at various times between 15 n-minutes and three hours. There was no blood contamination in any of the samples taken from the proximal portions of the T-port or the syringes themselves. This study has significant implications for both patient safety and cost savings.
Dr. A. Layon and associates found an interesting difference in the ability of bacterial species to survive contact with the soda lime used in C02 absorbers. They found that ' was killed after the briefest contact with soda lime granules whereas Mycobacterium Avium survived up to one hour in direct contact. Of equal interest is their additional finding that both bacterial species, in an aerosolized medium, passed readily through the soda lime, i.e., between the granules.
The authors of all the above four studies state that further study is required to clarify the implications for clinical practice.
Dr. Palmer is Professor of Anesthesiology at the University
of Colorado Health Sciences Center, Denver; Dr. Guyton is Assistant Professor
of Anesthesiology at the University of Mississippi SOM/Medical Center,
Jackson; Dr. Morell is Assistant Professor of Anesthesiology at The Bowman
Gray School of Medicine of Wake Forest University, Winston-Salem, NC, and
Dr. Zeitlin is from the Brigham and Women's Hospital, Boston, and is an
Instructor in Anesthesia, Harvard Medical School.
Carbon Monoxide: What Should We Do?
Editor's Note: Reports in the last two APSF Newsletters concerning CO toxicity from the interaction of halogenated ether anesthetics and C02 absorbents have received a great deal of attention. Note that the experimental conditions in which this phenomenon can be induced on a lab bench involve absorbents deliberately dried to a very abnormally low (or absent) water content a highly unusual situation. Questions have been raised by Newsletter readers as to what all this means, particularly for daffy anesthetic practice in the O.R. An experienced observer of anesthesiology who also has a background in related research provides perspective and context through his opinions on these developments:
by Ralph A. Epstein, M.D.
Clinical decisions are most difficult when there is incomplete scientific knowledge. This is currently the situation the clinician faces in deciding how to react, if at all, to recent reports of the potential threat of anesthesia-induced carbon monoxide toxicity.
Carbon monoxide is toxic in very low concentrations. The severity of toxicity depends both on the duration of exposure and on the concentration inhaled. Other influencing factors include the level of exercise and coexisting medical conditions. From a practical standpoint, exposure to greater than 50 ppm for eight hours should be avoided. Even brief exposure to greater that 200 ppm is considered hazardous. Carbon monoxide reacts with hemoglobin to form deoxyhemoglobin. Textbooks of environmental medicine provide standard tables which predict carboxyhemoglobin level as a function of carbon monoxide concentration in inspired air and of duration of exposure. (1) For example, exposure to 1,000 ppm for one hour would be expected to produce 30% carboxyhemoglobin.
The toxicity of carbon monoxide is by no means limited to direct replacement of oxygen on hemoglobin. Even a small concentration of carboxyhemoglobin causes the oxygen-hemoglobin dissociation curve to shift sharply to the left, thereby preventing the normal unloading of oxygen in the capillary bed. Thus, the patient can suffer tissue hypoxia while the blood partial pressure of oxygen is high. Moreover, carbon monoxide also poisons the cytochrome enzyme system, further depressing the utilization of oxygen.
It is difficult to know exactly at what carboxyhemoglobin levels mortality occurs because most victims receive therapeutic oxygen between the time of exposure and arrival at a health care facility where the carboxyhemoglobin level is determined. However, the peak level can be estimated from the known half W of carboxyhemoglobin. It is generally thought that death may result from carboxyhemoglobin levels of 50 percent in young healthy victims. Patients with underlying cardiovascular disease may be at risk from significantly lower levels.
In recent years, anesthesiologists have not concerned themselves very much with iatrogenic carbon monoxide poisoning. This is in part because closed circle anesthesia fell out of favor after cyclopropane disappeared from clinical use. With closed circle anesthesia, there had been occasional reports of carbon monoxide build up in the anesthetic circuit, especially in patients who had required significant blood transfusions. Smoking by the blood donor and hemoglobin destruction were thought to be factors.
Confusion and Concern
Reports and discussion of iatrogenic carbon monoxide toxicity in the last two issues of the APSF Newsletter have therefore caused both confusion and concern in the anesthesia community. This has been compounded by the fact that the Newsletter is not a peer-reviewed journal. The information was therefore presented as "news,' rather than in sufficient detail to allow full critical review. Nevertheless, the practicing anesthesiologist needs to decide whether the facts, as they are now known, require changes in clinical practice.
In the Summer issue of the Newsletter, Lentz' reported a case of unanticipated carbon monoxide toxicity. Although it was not stated until an explanatory note appeared in the Fall issue, the patient was receiving desflurane. The author astutely recognized that the case occurred Monday morning and postulated that something happened to the anesthesia system during prolonged disuse which ultimately led to the release of carbon monoxide. Without understanding the specific mechanism, he made the common sense (but probably incorrect) recommendation that, after a weekend of disuse, the anesthesia system should be purged with a high flow of fresh gas prior to use. This seemed reasonable, particularly because it did not appear that there would be any disadvantage from such a strategy.
In the same Summer issue, Moon' reviewed 29 recent cases of high levels of carboxyhemoglobin from three institutions. AU occurred after the anesthesia machine had been unused for at least two days. Moon reported, however, that he was unable to detect clinically significant amounts of carbon monoxide after experimentally exposing anesthetic agents to soda lime. He postulated that carbon monoxide might be adsorbed by soda lime and then released after a period of disuse. Again, flushing the system with a high fresh gas flow seemed reasonable.
Other Monday Events
This was not the first time that an adverse event had been associated with an anesthesia machine that had been unused over a weekend. Over a decade ago, we had noted that inhalation inductions in children were sometimes prolonged on Monday mornings. (4) In a series of studies, we showed that, with our particular anesthetic circuit, the soda lime dried out if the fresh gases were inadvertently left flowing over the weekend. The dry soda lime then adsorbed huge quantities of inhalation agents, markedly slowing induction. The amount adsorbed was roughly proportional to the degree of absorbent drying.
In the Fall issue of the Newsletter, Fang and Eger (5)' shed additional light on the carbon monoxide problem. In brief, they reported that desflurane, enflurane and isoflurane all broke down in the presence of purposely dried carbon dioxide absorbents, releasing very high concentrations of carbon monoxide. They mentioned (without presenting specific data) that halothane and sevoflurane produced very little carbon monoxide.
In this laboratory situation, the concentration of carbon monoxide produced was alarmingly high. With the worst case combination of desflurane and completely dry barium hydroxide lime, the carbon monoxide concentration was almost 20,000 ppm. Desflurane produced a carbon monoxide concentration of about 15 times isoflurane and barium hydroxide lime about two times soda lime. However, even the best case combination of isoflurane and completely dry soda lime produced a concentration of 500 ppm, about 10 times more than is reasonable for chronic exposure. Fortunately, even moderate degrees of hydration of the absorbents greatly decreased the concentration of carbon monoxide produced. No carbon monoxide was produced in the presence of normally hydrated absorbents with any anesthetic agent.
[t is difficult to know what to do with all of this data. Though much of it illuminates important concepts, the data is really tangential to the clinical question. For example, under what clinical conditions (if any) do absorbents become sufficiently dry to cause halogenated ethers to break down to form carbon monoxide? Flow rate of dry gases, duration of flow and the design details of actual absorbers in clinical use certainly must be considered. What is the role of details of the circuit design? When we Discovered in 1982 the adsorption of anesthetics by soda lime that had become inadvertently dry, we were using a pediatric circuit specifically designed to humidify anesthetic gases. The dry fresh gases entered this circuit between the inspiratory valve and the absorber; the 'pop-off' valve was located between the absorber and the expiratory valve. Thus, unlike a modem circuit, all of the dry gas had to pass through the soda lime, even if the circuit was detached from the patient. This is not true with most modem circuits. Moreover, how rapidly does each of the currently used absorbents give up water and how rapidly are they rehydrated by the release of water from neutralization of carbon dioxide and by adsorbing exhaled water vapor? Finally, we cannot even be completely certain at this point whether the carbon monoxide levels found in these patients were due solely to the mechanism discovered by Fang and Eger.
It would be easy to decide what to do if there were sufficient, confirmed, peer reviewed data. At a minimum, I would like to know the the course of carbon monoxide concentration measured on both sides of the absorber during clinical conditions. I would particularly be interested in the time course of carbon monoxide production during rehydration of the dried absorbent.
Still, the clinician needs to decide what best to do in the face of an incomplete understanding of this potentially dangerous phenomenon. I believe " is the time for a measured response rather than for a radical change in clinical practice. We need to remember that modern anesthetics, as currently used with absorbents, are actually very safe. I would not switch immediately to sevoflurane or halothane. The former is not yet available in the United States and the latter, for understandable reasons, has been largely replaced with more modern drugs. I would not even discontinue the use of desflurane, when indicated, in favor of isoflurane, even though, under very specialized laboratory conditions using completely dry absorbents, desflurane produces 15 times more carbon monoxide than isoflurane. These laboratory conditions may represent only very rare and brief clinical conditions. Likewise, the difference between soda lime and bariurn hydroxide lime is relatively small, and it is not yet known whether this difference exists under more typical clinical conditions. Furthermore, I would not, at this point, redesign the anesthesia machine to guard against dry absorbent.
My reticence to quickly make large changes in practice does not reflect my lack of concern about carbon monoxide toxicity. On the contrary, I believe that academic and industrial research is urgently needed to better delineate the problem. Without question, additional data might very well alter my reticence, but I can only base my actions on data that is currently available.
I would, however, modify my behavior to adhere more carefully to good clinical practice. It is clear to me that there are several good reasons not to allow carbon dioxide absorbents to dry out. I would first make sure that I understood the details of the anesthetic circuit I was using. In the very unlikely event that I were using a circle system in which the fresh gas inlet was located between the expiratory check valve and the absorber (so that all of the fresh gas was forced through the absorbent even when the Wye piece was open), I would completely change the absorbent at the start of each day and avoid the prolonged use of high fresh gas flows.
If I were using a conventional circle system, I would simply take care to turn off the fresh gas at the end of each case. I would instruct my technicians to follow up on this in the event I forgot. If I could not be sure that this would be done reliably, I would change the absorbent more frequently, perhaps every Monday morning. I believe this is all that is required by the facts as we now know them.
Dr. Epstein, Professor of Anesthesiology at the University of Connecticut, is a member of the Editorial Board of the APSF Newsletter.
1. Kurt TL. Chemical Asphyxiants. In: Environmental and Occupational Medicine, 2nd Ed, edited by WN Rom. Boston: Little, Brown and Co., 1992, p 541.
2. Lentz RE. CO poisoning during anesthesia poses puzzles. APSF Newsletter 9:14-15,1994.
3. Moon RE. Cause of CO poisoning, relation to halogenated agents still not dear. APSF Newsletter 9:14-16,1994.
4. Grodin WK. Epstein RA. Halothane adsorption complicating the use of soda lime to humidify anesthetic gases. Brit. J. Anaesth. 54:555-559,1982.
5. Fang ZX. Eger El. Source of toxic CO explained: -CHF2 anesthetic + dry absorbent. APSF Newsletter 9:25-30,1994.
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Dr. Tammy Yachabach Euliano
Dr. Tammy Yachabach Euhano has been named the 1995 APSF Young Investigator. Dr. Euhano will extend the physiologic models of the Gainesville Anesthesia Simulator to accurately reflect the obstetric patient and will then develop scenarios to be used in conjunction with simulation-based training. Her work will include the development of a structured, simulator-based learning curriculum for obstetrical anesthesia, and she will evaluate the learning effectiveness of the curriculum by comparing it to a traditional approach. Her investigative project will examine four specific hypotheses about how physician understanding, rate of acquisition of knowledge, and ability to diagnose and treat specific complications will differ between simulator and traditional curricula. She will also attempt to determine if there are differences in either comfort or confidence levels of residents who are trained using simulator-based curricula versus traditional curricula.
Dr. Euliano received her M.D. degree from the University
of Florida College of Medicine and completed her internship and then residency
in anesthesia there. She will be working under the guidance of Dr. Michael
Good, Associate Professor of Anesthesiology, with whom she has already
been collaboration on various aspects of enhancing anesthesia training
via innovative technologies. The results of Dr. Euliano's work will add
obstetric skills to simulator-based training and development curricula.
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As this editorial is being written, Thanksgiving is upon us. It occurs to me that we should give thanks for the success all of us have had in the past decade in making the administration of anesthesia such a safe undertaking. While the progress is truly remarkable, all is not perfect, however. Perhaps it never will be. I am aware of one anesthesia mishap in this country this year which is reminiscent of the early 1980's in which a breathing system disconnect during mechanical ventilation was unrecognized, resulting in the death of a young man. The anesthesia machine was old and without appropriate alarms.
Today, anesthesia safety covers an ever-broadening range of subject matter. During the last several months there has been correspondence in this Newsletter concerning the role of the aging anesthesiologist. Recently I was asked to speak to an anesthesia society about aging as well as fatigue. In preparing for the talk, I reviewed Dr. David Caba's chapter on "Human Work Environment and Simulators" in the new edition of Miller's textbook, which contained a section entitled 'Aging.' Everyone should read it.
Also, I was given a list of questions by the society concerning problems they have among their membership in working out solutions in different groups for the anesthesiologists who are getting .older." On that basis, I prepared a questionnaire and sent it out in a most-unscientific manner to some 75 anesthesiologists.
I received more than 50 replies. For your information, I give you the data. The questions and graphs of the responses are shown. In addition, I received a number of comments, some of which are noted (the comments were not randomly selected).
Kenneth W. Travis, M.D., who initiated the recent correspondence concerning advancing age among anesthesiologists, has written a research grant, much more scientifically designed than my questionnaire, to examine further the role of anesthesiologist aging as it relates to performance and, potentially, patient safety. Hopefully over the next year or two we will have more answers.
Have a safe 1995.
Ellison C. Pierce, Jr., M.D.
President, Anesthesia Patient Safety Foundation
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"I view this through my own 68-year-old point of view and I guess, like most of us, I feel like I'm in the slower aging cohort.
"My personal observations about the older physician, that is somebody over the age of 60 (now I'm calling on my Medical Board background), is that these physicians tend to get into 'trouble' more frequently than younger physicians do.
"I think it will be an exceptional anesthesiologist who reaches retirement age and carries a full clinical load, takes night call, and maintains the intensity of cases.
"I think in most groups that seniority warrants "perks."
"Most physicians desire to retire sooner, rather than later. Have never had to deal with a physician unable to perform duties because of age.
"Senior members should recognize that they may not be able to work as much as they would like to in order to be sure that they won't have to work more than they care to. Younger members should realize that any rules adopted will eventually apply to them.
"I don't feel that an anesthesiologist needs to have razor sharp reflexes as few events occur in anesthesia that require a response in that time frame. The speed of one's reflexes should not be confused with a lack of vigilance this is where the experienced anesthesiologist has a significant edge over the neophyte by being able to recognize the initial, subtle changes. This permits early, low key intervention rather than heroic rescue maneuvers. Good luck is the end product of good design.
"Don't try to establish 'mandatory" number of hours that 'elderly" anesthetists can work, or mandatory retirement ages. These should be flexible and depend on each individual.
"The manner in which we handled this issue with our senior partner served us well. Step I was to delete call at equal pay and to select less stressful cases for him. Step 2 was to encourage him to work fewer weeks per year or to work part-time on a per them basis for several years. During this time we utilized this person for vacation relief during regular hours. At Step 3 this person voluntarily retired with his prestige and dignity intact.
"I really feel that one must handle this issue on a case-by-case basis.
"Our Board has designated a fatiguing call as any 24 hour call period in which one does not get at least six hours of uninterrupted sleep during the last 12 hours of the call period. Anesthesia personnel should not sign up to give anesthetics in any clinical context or location after taking a designated fatiguing call."
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APSF Treasurer Notes Accountability
To the Editor
Following up on discussion that occurred in conjunction with the APSF annual meeting in October at the time of the ASA meeting, I take this opportunity to inform all ASA/APSF members that the APSF forwards complete financial statements to the ASA three times each year. Additionally, APSF officers communicate frequently with the ASA Treasurer and Assistant Treasurer regarding financial matters and these ASA officers are invited to the summer APSF Executive Committee meeting to discuss any issues relating to APSF finances.
Casey Blitt, M.D. Treasurer, APSF
CO Researcher Notes, Compares CO Production From Different Absorbents
Not to be Basis for Choice
To the Editor
Data presented in our recent publication' concerning the production of carbon monoxide (CO) from the degradation of volatile anesthetics by carbon dioxide absorbents was not intended to be used as the sole basis for choosing a particular absorbent or anesthetic.' The data show a greater production of CO from a given anesthetic exposed to Baralyme brand absorbent at comparable levels of absorbent dryness. Dryness is important because drying of the absorbent to below-normal levels of water content increases production of CO, particularly as complete dryness is approached. If fresh, dry gas flows over, and dries the soda lime and Baralyme equally, CO production might be particularly increased with Baralyme. However, this presumes equal drying of the absorbents. Reports assert, without publication of supporting comparative data, that the hydrate of barium hydroxide in Baralyme' resists drying more than the mixture of water and absorbent found in soda lime.',' If true, this would modify the presumption of equal drying, and thus may balance or change the relative likelihood of CO production associated with the use of one absorbent as opposed to the other. Further studies will be needed to assess these and other factors as determinants of absorbent and anesthetic choice.
Edmond I. Eger, II, M.D.,
Professor and Vice Chairman for Research University of California, San Francisco, CA
1. Fang Z, Eger El II. Factors causing the production of carbon monoxide from the action of carbon dioxide absorbents on volatile anesthetics. APSF Newsletter 1994; 9: 25-28.
2. Andrews J. Inhaled anesthetic delivery systems. ed: R Miller, Anesthesia, 4th edition. New York: Churchill Livingston, 1994: p. 207.
3. Adriani J, Batten D. The efficiency of mixtures of
barium and calcium hydroxides in the absorption of carbon dioxide in rebreathing
appliances. Anesthesiology 1942; 3: 1-10.
Is It OK to Read During OR Cases?
To the Editor
Since beginning my anesthesia career in 1977, I have ofttimes seen anesthesia practitioners reading novels, newspapers, magazines, and even, sometimes, professional journals during cases. When I attempted this myself, I realized that I sometimes neglected my charting, did not notice significant events, or did not hear questions addressed to me by the surgeon. I decided that reading during cases was not a safe practice and ceased to do so other than to look up a quick reference. Recently I was shocked when our Chief of Surgery said that he had never seen an anesthesia provider who did not read during cases.
I believe that distracting oneself from monitoring one's patient results in a lack of vigilance that could lead to a problem. But some of my peers feel that modern monitoring equipment with built-in alarms makes reading during cases, especially regional anesthetics, an acceptable practice. I would like to see a discussion of the practice of reading during cases -both related medical literature and non-medical "pleasure reading" -in an open forum such as the APSF Newsletter. C. Carl
Bostek, Lt. Col., USAF
Chief, Nurse Anesthesia Services Elmendorf AFB, AK
No Need to Avoid Spinal Narcotics
To the Editor
I read with interest the article by Dr. C.D. Blitt and associates published recently in the APSF Newsletter. However, I disagree with No. 2 of their "New Guidelines' which states: "Avoidance of subarachnoid opioids.' My concern is that they gave no scientific evidence to support their statement while, historically, the safety of subarachnoid opioids has been established, provided the type is carefully chosen and the dose is properly administered. For example, we have been adding 0.2 mg morphine to spinal bupivacaine for cesarean section for many years' and published the safety of the technique in a prospective study in 19911. In fact, no special monitoring equipment or place for postoperative stay is required if the dose of intrathecal morphine is limited to 0.2 mg. For vaginal delivery, intrathecal opioids, either alone or part of combined spinal-epidural technique, have been found useful and safe." We have been routinely using intrathecal opioids for labor. Therefore, if 'avoidance of subarachnoid opioids' is chosen to be the guideline for a certain group of physicians, I hope this is not misinterpreted to be the standard of care for all. Otherwise, their statement could have serious medicolegal consequences.
Ezzzat 1. Abouleish, M.D. Department of Anesthesiology
The University of Texas Health Science Center Houston, TX
1. Blitt CD, Kaufer-Bratt C, Ashby J, Caillett JR: QA program reveals safety issues, promotes development of guidelines: Arizona practice is model. APSF Newsletter 9:17-19,1994.
2. Abouleish El Rawal N, Fallon K, Hernanez D:Combined intrathecal morphine and bupivacaine for cesarean section. Anesthesia & Analgesia 67:370-374,1988.
3. Abouleish El Rawal N, Rashad N: The addition of subarachnoid morphine 0.2 to hyperbaric bupivacaine for cesarean section: A prospective study of 856 cases. Regional Anesthesia 16:137-140,1991.
4. Abouleish El Rawal N, Tobon-Randall 8, Rivera-Weiss M, Meyer B, Wu A, Rashad MN: A clinical and laboratory study to compare the addition of 0.2 mg morphine, 0.2 mg epinephrine or their combination to hyperbaric bupivacaine for spinal anesthesia in cesarean section. Anesthesia & Analgesia 77:457-462,1993.
5. Abouleish A, Abouleish El Camann W: Combined spinal epidural analgesia in advanced labor. Canadian Journal of Anesthesia 41: 575-578,1994.
6. Camann W: Intrathecal sufentanil for labor analgesia: effect of added epinephrine. Anesthesiology 78: 870874,1993.
7. Howet JE, Arkoosh VA, Norris MC, Huffnagle HJ, Silverman NS, Leighton BL: Comparison among intrathecal fentanyl, meperidine, and sufentanil for labor analgesia: Anesthesia & Analgesia 75:734-739,1992.
8. Coldwell LE, Rosen MA, Schnider SM: Subarachnoid morphine
and fentanyl for labor analgesia: efficacy and adverse effects. Regional
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by Mark P. Fritz, M.D.
Several scientific papers presented at this year's annual meeting of the American Society of Anesthesiologists demonstrate how substantial cost savings can be safely achieved through relatively simple changes in practices. Anesthesiology departments are under increasing economic pressures to reduce costs. As various cost saving measures are considered, it is important that we look at how we can best reduce costs without compromising the quality of care and patient safety. The following is a composite summary of the scientific papers presented in the sessions on "Cost Containment in Anesthesia."
Anesthetic drug costs are a major portion of pharmacy budgets. Costs of anesthetic drugs (particularly vecuronium, isoflurane, and propofol) represent significant expenses in the hospital's pharmacy budget.
Five agents account for more than 80% of anesthetic drug expenditures. Vecuronium, isoflurane, propofol, midazolam, and atracurium account for the vast majority of a typical departments expenses for pharmaceuticals.(1,2,3,7,9)
More judicious use of expensive intermediate-acting nondepolarizing neuromuscular blocking agents results in substantial savings. Restricting intermediate-acting agents to specific indications (rapid sequence inductions where succinylcholine is contraindicated, and cases of less than 60-90 minutes duration) results in dramatic savings.(1,2,9) Education on price of agents and alternatives (pancuronium/metocurine) may be important.(1,2,7,8,9) Properly using multidose vials or having the pharmacy prepare doses in labeled and tamper-sealed syringes can reduce wastage of unused syringes."
Use lower fresh gas flows when using volatile agents. A large number of practitioners use greater than 4 L/min total fresh gas flow (FGF) with inhalational agents. Reducing FGF after the initial 'wash-in' period results in substantial savings in volatile agents. (2,3,4,7,8) Many pediatric hospitals use low-volume pediatric circle circuits rather than nonrebreathing (Mapleson D, Bain, Jackson-Rees) circuits to reduce FCF and conserve inhalational anesthetics.(2)
Using fentanyl (20ml) rather than more expensive narcotics. Some savings can be achieved through using 'economy size' ampules of fentanyl (i.e., one 20 ml ampule rather than two 10 ml ampules) and by using equipotent doses of fentanyl in place of sufentanil and alfentanil. (5,7,8)
Reduce wastage of propofol and midazolam. Large amounts of propofol and midazolam are wasted every day (leftover propofol from 50 ml vials and midazolam from 5 mg or 10 mg vials). Better planning of anticipated dose can help to reduce waste.(9)
Compare the costs of various vendors regularly. The "disposables" market is quite competitive and you can often find vendors with comparable products at a lower cost.(7)
Consider going back to re-usable products. Many departments can realize significant savings by returning to reusable supplies (such as pulse oximeter probes and breathing circuits). (8) You must remember to include the original purchase cost plus the processing costs (cleaning & disinfecting) and eventual replacement costs when comparing reusables to disposables.
Reduce wastage of emergency drugs through pharmacy 'batching' of labeled, sealed syringes. A large number of syringes are never used, but were drawn up in case they were needed (succinylcholine, ephedrine, lidocaine), Pharmacies can often prepare unit dose syringes, properly labeled and sealed, that can be saved until they expire.(2,5,9)
Anesthesiologists have a poor understanding of the costs of the drugs they are using. Price posting and educational programs can improve cost consciousness. Residents and faculty had difficulty in accurately estimating the costs of various anesthetic drugs and supplies. Posting the costs of various agents and having educational programs may increase cost awareness, and possibly modify practice habits(3,6,7,8,9)
Pharmacy markups may mask some cost savings. Some hospital pharmacies charge patients and insurance carriers much more than the true acquisition costs. Cost savings that are realized may be obscured by pharmacy pricing policies.''
No increase in morbidity or mortality was reported in implementing these cost-containment measures. Many of these papers specifically looked for any complications that could be attributed to cost containment measures. The sample sizes are small, but no additional complications were reported.
In summary, it would seem that significant savings can be realized by most departments through small changes in daily practices without compromising patient safety.
Dr. Fritz is from the Mason Clinic in Seattle, WA, and chaired the 1994 ASA Subcommittee on Patient Safety, Epidemiology, and Education section of the Annual Meeting.
1. Freund, P. Anesthesiology 1994 Vol 81(3A):Al 197.
2. Holzman, R. Anesthesiology 1994 Vol 81 (3A): A1198.
3. Williams, M. Anesthesiology 1994 Vol 81 (3A): A1199.
4. Williams, M. Anesthesiology 1994 Vol 81 (3A): A1200.
5. Greenberg, C Anesthesiology 1994 Vol 81 (3A): A1202.
6. Shapiro, D. Anesthesiology 1994 Vol 81(3A):A1203.
7. Becker Jr., K. Anesthesiology 1994 Vol 81 (3A): A1204.
8. Parks, J. Anesthesiology 1994 Vol 81 (3A): A1205.
9. Munshi, C. Anesthesiology 1994 Vol 81 (3A): A1206.
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by John H. Eichhorn, M.D.
Technical and scientific exhibits offered at the ASA meeting in October contained many patient safety-related ideas and products.
Among the scientific exhibits, definitely the most dramatic was entitled 'Beyond the Walls' (see photos on Pages 45, 48, and 52) which displayed the hazards discovered in investigations of problems with medical gas and vacuum systems within the walls of medical facilities. Real-life, very frightening examples of contamination, obstruction, and misconnection of pipelines, often oxygen pipelines, were displayed. Even a dead bird in a medical air system inlet (the cause of a foul odor in the compressed air) was exhibited in a glass case. The elaborate, comprehensive, thought-provoking exhibit was prepared by Dr. Ervin Moss, Chairman of the APSF Subcommittee on Medical Gas and Vacuum Systems, Dr. Joseph Pepper of Ohmeda, Mr. Fred Evans, President of Medical Gas Management of Bethany, Oklahoma, Dr. Todd Peterson of University of Arizona, Mr. Tom Nagle of Ohmeda, and Mr. Pete Winboume of Medical Gas Management. AU who viewed this exhibit gained new insight into the often incredible substances and problems that can plague medical gas pipeline systems and, thus, often create very serious anesthesia patient safety problems that are obscure and difficult to identify because they are "beyond the walls.'
Several exhibits were similar to prior presentations. Notable among these was display of a device that helps guide an endotracheal tube into the trachea blindly through the use of multiple capnographic samples. A new scientific exhibit this year offered information about an instrument that does sound wave confirmation of correct intubation of the trachea.
Airway issues were prominently featured in the scientific displays. There was an excellent presentation of the history and historical perspective of airway management (see photo on Page 48). Several displays dealt with the teaching of airway techniques, including a description of the 'airway rotation' for residents at the University of California, San Diego. Also featured was an 'interactive hypermedia approach" to the teaching of the ASA difficult airway algorithm from Wilford Hall Medical Center in Texas. Further, the department at Rush Presbyterian in Chicago outlined its integrated program in airway management and displayed the instructional material used to teach fiberoptic intubation techniques.
Other scientific displays with specific safety implications included demonstration of a new device used as an epidural needle introducer intended to make it easier to find the epidural space while reducing the likelihood of unintended events and also a presentation based on the need to correctly diagnose the rare but devastating event of failure of the oxygen supply to the cardiopulmonary bypass machine during cardiac surgery.
Among the technical exhibits, there were the standard, expected displays of multiple possible mix-and-match configurations of what are now traditional electronic monitors for various physiologic and anesthetic parameters.
As with the scientific displays, airway equipment, devices, and techniques appeared very prominently in the exhibit hall. There were multiple new devices to aid in the manipulation and negotiation of difficult airways. Several inventive and even radical variants of the traditional laryngoscope were displayed, by both new and established manufacturers. New blade configurations for traditional laryngoscopes were touted as significant advances. A new directional stylette to assist in tube placement seemed to offer novel ways to direct a tube in unusual ways. Once the tube has been successfully passed, several manufacturers offered 'improved" ways to secure the tube in place and ensure safety from this aspect.
Parenthetically, there were several exhibits offering reportedly better ways (some involving tapes and hooks) to secure catheters of various, types in place for the desired interval.
Patient temperature maintenance again figured strongly in the technical exhibits. Combinations of traditional devices were offered, but there seemed to be no startling new advances in technology. Adding humidity to breathing systems was the main theme of six displays.
Several information management systems were prominently displayed among the exhibits. Teaching programs, patient information retrieval, and literally mountains of information on CD-ROM were offered as new advantages of these systems.
While possibly more provider-safety oriented than directly impacting patient safety, needleless injection systems were stressed heavily among the exhibits. There were at least ten different displays in place.
Overall, again this year, there were probably not any profound breakthroughs equivalent to "the next pulse oximeter' displayed at the meeting. There were, however, several innovative and creative ideas and products shown that eventually may or even likely will have incremental positive effects on anesthesia patient safety.
Dr. Eichhorn, Professor W Chairman of Anesthesiology at
the University of Mississippi, is an APSF Director and Editor of the Newsletter.
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by Ellison C. Pierce, Jr., M.D.
ASA Videotape 22, 'Crisis Management in Anesthesia,' was prepared in consultation with David Gaba, M.D., and his colleagues, including Dr. Stephen Howard. This production provides an overview of the key principles of crisis resource management and focuses on the mandate for the anesthesiologist to take charge when a life-threatening crisis develops during surgery.
Practical guidelines are offered on appropriate allocation of attention, management of all available resources, exercise of strong leadership, sensible distribution of the workload, and effective communication with the OR team.
Dr. Gaba's colleagues from Stanford and the Palo Alto Veterans Affairs Medical Center play the staff roles during two engaging vignettes simulating evolving crises during anesthesia to allow the viewer to see the principles in practice. One is centered on a 20-year-old man having knee surgery under general anesthesia and the other a 72-year old patient with COPD undergoing splenectomy.
Both desirable and undesirable behaviors under stress are demonstrated and these behaviors are subsequently critiqued by Dr. Gaba and Dr. Howard.
The film provides a memorable learning experience for every anesthesiologist who lives with the pressure of a potential crisis case after case on a daily basis.
This videotape was shot on location at the Palo Alto Veterans Affairs Medical Center in California. In addition to the primary author, Dr. Gaba, contributions by the following are acknowledged: Steven K. Howard, M.D., Kevin J. Fish, M.D., Richard Botney, M.D., and Brendan Flanagan, M.D.
The production of 'Crisis Management in Anesthesia' was funded by the Burroughs Wellcome Company; and distribution was begun in the fall of 1994 by Burroughs Wellcome. The film was produced by GWF Associates, Holmdel, NJ.
ASA Videotape 23, 'Memory and Awareness in Anesthesia,' was prepared in consultation with Dr. Peter Sebel, Dr. Charles McLeskey and Dr. Robert Caplan. This film alerts the anesthesiologist to the problem of patient awareness during anesthesia, a serious issue considering the potential consequences. Since about 70% of awareness episodes may result from the choice of anesthesia technique, it is imperative that anesthesiologists are mindful of contributory factors. Reported incidence figures may represent just the 'tip of the iceberg.'
During this film, which describes conditions that contribute to intraoperative awareness, the consultants provide specific recommendations for avoiding the occurrence of unintended and undesirable patient awareness during anesthesia. In addition, Dr. Caplan points out techniques for a postoperative patient interview by the anesthesiologist to determine whether awareness might have occurred. The responsibilities of the anesthesiologist, if an awareness episode has occurred, are then explained.
The importance of vigilance in preventing patient awareness is underscored by the testimonial of Ms. Andrea Thaler, a patient who states her episode of awareness was traumatic, with longterm negative sequelae.
Dr. Sebel concludes that intraoperative patient awareness can be prevented by adherence to definitive recommendations combined with careful monitoring of both patient and equipment.
The ASA funded the production of 'Memory and Awareness in Anesthesia,' and Burroughs Wellcome Company will distribute it in the Winter
of 1994-5. The film was produced by GWF Associates, Holmdel, NJ.
Dr. Pierce is president of APSF and executive producer
of the ASA Patient Safety Videotape Series.
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Publications from Past Grant Sponsored Research Number over 100 to Date
by Jeffrey B. Cooper, Ph.D.
The Anesthesia Patient Safety Foundation has selected three projects to receive research grant awards beginning on January 1, 1995. This was an especially competitive year; twenty-six applications were submitted. There were many new themes represented in the proposals and a noticeable improvement in the quality of the writing and experimental design.
This year's grants were awarded to:
Mark A. Warner, MD and Co-investigator Denise J. Wedel, MD, Department of Anesthesiology, Mayo Clinic
Title: Profiles and Outcomes of Anesthetized Patients Who Have Undiagnosed Muscular Dystrophy.
This project will address the recent, controversial proposed restriction of succinylcholine use by the Food and Drug Administration. The objective of the study will be to determine the risk of an anesthesiologist encountering a young patient with undiagnosed muscular dystrophy (MD) and the rates of mortality and morbidity associated with anesthetics for patients with undiagnosed MD. If sufficient mortality or major morbidity are identified, a case-control study will be performed to determine risk factors for those outcomes.
The study will use as its source of data the unique database that has been assembled from patients in Olmsted County, MN, and the Mayo Clinic between 1957-1993. An earlier grant from the APSF to the same principal investigator contributed to analysis of other aspects of this database, resulting in numerous publications (see below). It is hoped that this study will provide more objective information that perhaps could be used to guide decision making concerning this timely issue.
Mark A. Warner, M.D.
Susan Black, MD, Department of Anesthesia, University of Florida, College of Medicine
Title: Prolonged Postoperative Cognitive Dysfunction in Elderly Patients
Prolonged postoperative cognitive dysfunction is a recognized, but poorly characterized postoperative complication. Dr. Black will lead an effort at one of eleven institutions, each studying 200 patients and adhering to the same protocol, to identify the incidence of PPOCD in elderly patients and test the hypothesis that there is a correlation between perioperative hypoxemia and this event.
The international multi-center study has its main funding from the European Community and involves ten European hospital sites. Data will be analyzed at the University of Eindhoven in Holland. This is a unique opportunity to develop a sufficiently large database to study an elusive problem. Prior experience in psychometric testing by key investigators in the group has lead to development of a well designed battery of tests that should better quantitate the higher cognitive functions related to memory, attention, concentration, shifting ability, speed of information processing and other functions.
Susan Black, M.D.
Davy C.H. Cheng, MD and Co-investigators Jacek Karski, MD, Charles Peniston, MD, Tirone David, MD, Alan Sandler, MD, Department of Anesthesia, The Toronto Hospital, University of Toronto
Title: Is Early Extubation Safe in Patients Following Coronary Artery Bypass Graft Surgery? A Prospective Randomized Controlled Outcome Study
Dr. Cheng will build on a completed pilot study to examine a question of intense current interest. The larger issue is also of special importance: increasing pressures to reduce health care costs present new challenges for patient safety. This investigation will use a randomized controlled trial to assess the safety of early extubation, which is becoming a practice following coronary artery bypass graft surgery and other major procedures in an effort to move patients through the perioperative system more quickly. The hypothesis to be tested is that a modified, low-dose narcotic technique with propofol and early tracheal extubation following CABG surgery is safe compared to 'conventional" high-dose narcotic anesthetic technique and later tracheal extubation.
Davy C.H. Cheng, M.D.
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The first APSF research grant awards were announced in 1986; the first projects were conducted in 1987. Since that time and including this year, there have been a total of 30 projects receiving grant awards in twenty different institutions with a total of over $ 1.1 million of funding support. These funds have particularly high leverage because they cannot be used for institutional overhead and because frequently the department involved provides additional support to the investigator. This is reflected in the large number of publications deriving from APSF supported research. Investigators funded during the years 1987 through 1992 inclusively have reported a total of approximately 50 articles published or in press and another 50 abstracts. A sampling of these is listed below with the principal investigator indicated in boldface. The diversity of topics supported by the APSF is indicated by the titles.
Sang CN, Berde CB, Safety in Pediatric Regional Analgesia Study Group. A multicenter study of safety and risk factors in pediatric regional analgesia. Anesthesiology, 1994 (in press)
Strafford MA, Wilder RT, Sethna NF, Berde CB. The risk of infection from pediatric epidural analgesia is low. Anesth Analg, 1994 (in press)
Berde CB. Convulsions associated with pediatric regional
anesthesia. Anesth. Analg. 75:164-6,1992 Lui SS, Paul GE, Carpenter RL, WU R: Prolonged P-R interval is a risk factor for bradycardia during spinal anesthesia. Regional Anesthesia, 1994 (in press)
Carpenter RL, Caplan RA, Brown DL, Stephenson CA, Wu R: Incidence and risk factors for side effects of spinal anesthesia. Anesthesiology 76:906-916,1992
Cohen MM, Duncan PG, Tweed WA, Biehl D, Pope WDB, Perry M, Merchant R. "The Canadian four centre study on anaesthetic outcomes: 1. Description of methods and populations. ' Can J Anaesth 39:420-429,1992
Cohen MM, Duncan PG, Pope WDB, Tweed WA, Biehl, MacWilliam L, Merchant R. "The Canadian four centre study on anesthetic outcomes E. Can outcomes be used to assess quality of care in anesthesia?" Can J Anaesth 39:430-439,1992
Duncan PG, Cohen MM, Biehl D, Tweed WA, Pope WDB, Merchant R, DeBoer D. "The Canadian four centre study of anaesthetic outcomes: III Are anesthetic complications predictable in day surgical practice?' Can j Anaesth 39: 440-448, 1992
Rolf N, Cote' CJ. Diagnosis of clinically unrecognized endobronchial intubation in pediatric anesthesia: Which is more sensitive pulse oximetry or capnometry? J Pediatric Anesthesia 2: 31-35,1992
Rolf N, Cote' CJ. Frequency and severity of desaturation events during general anesthesia in children with and without upper respiratory infections. j Clin Anesth 4: 200-203,1992
Cote' CJ, Rolf N, Liu LM, Goudsouzian NG, Ryan JF, et
al. A single-blind study of combined pulse oximetry and capnography in children. Anesthesiology 74:9W987,1991
Gaba DM, Howard SK, Fish KJ, et al. Anesthesia crisis resource management training: Teaching anesthesiologists to handle critical incidents. Aviat. Space Environ. Med. 63: 76370,1992
DeAnda A, Gaba DM. The role of experience in the response to simulated critical incidents. Anesth Analg 72:308315,1991
De Anda A, Gaba DM. Unplanned incidents during comprehensive anesthesia simulation. Anesth Analg 71: 77-82, 1990
Gaba DM, De Anda A. The response of anesthesia trainees to simulated critical incidents. Anesth Analg 68.444-451,1989
Gaba DM, De Anda A. A comprehensive anesthesia simulation environment: Recreating the operating room for research and teaching. Anesthesiology 69:387-394,1988
Good ML, Gravenstein JS. Training for safety in an anesthesia simulator. Sern Anesth 12: 235-n, 1993
Hartniannsgruber M, Good ML, Carovano RG, Lampotang S, Gravenstein JS. Anasthesiesimulatoren and traingsgerate. Anaesthetist 42:46249,1993
Loeb RG, Brunner JX, Nathan L. Pace, MD. The Utah anesthesia machine. Anesthesiology 70:999-1007,1989
Sa=a SK, Schork MA, Guinto FC. A study of radiologic imaging techniques and airway grading to predict a difficult endotracheal intubation. I Chn Monit, 1994 (in press)
Schwid HA. Computer simulations and management of crifical incidents. Academic Medicine 69: 213,1994
Schwid HA, (YDonnell D. Anesthesiologists' responses to simulated critical incidents. Anesthesiology 76: 495-501,1992
Schwid HA, (YDonneU, D. Educational malignant hyperthermia simulator. j Chn Monit 8: 201-208,1992
Schwid HA, O'Donnell D. The anesthesia simulatorrecorder: A device to train and evaluate anesthesiologists' responses to critical inddents. Anesthesiology 72: 191-197, 1990
Warner MA, et al. Lower-extremity motor neuropathy associated with surgery performed on patients in a fithotomy position. Anesthesiology 81: 6 12,1994
Warner MA, et al. Clinical significance of pulmonary aspiration during the perioperative period. Anesthesiology 78: 56-62,1993
Warner MA, et al. Major morbidity and mortality within one month of ambulatory surgery and anesthesia. JAMA 270: 1437-1441,1993
Weinger MB, Hemdon OW, Zomow MH, Paulus MP, et al. An objective methodology for task analysis and workload assessment in anesthesia providers. Anesthesiology 80: 77-92, 1994
Orr JA, Westenskow DR. A breathing circuit alarm sys, tern based on neural networks. J Chn Monit 10: 101-109,1994
Myh,ea KC, Orr JA, Westenskow DR. Integration of monitoring for intelligent alarms in anesthesia: Neural networks can they help? J Chn Monit 9: 31-37,1993
Westenskow DR, Orr JA, Simon FH, Ing D, Bender Hj, Frankenberger H. Intelligent aknns reduce anesthesiolo&es response time to critical faults. Anesthesiology 77:1074-1079, 1992
Dr. Cooper is an Aswiate Professor of Anaesthesia at Haroard
Medical School and Director 0 Bionxdkal Engineering, Maswchusetts General
Hospital, Boston. He has been the chairman of the APSF Committee on Scientific
Evaluation since 1989.
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Pierce Award Winners: One of the 1994 Ellison C. Pierce Auards given by the APSF at the ASA Annual Meeting for the best exhibit(s) related to anesthesia patient safety went to members of the APSF Subco?nmittee on Medical Gas and Vacuum Systems: (L-R) Mr. Pete Winbourne of Medical Gas Management, Bethany, OK; Ervin Moss, M.D., Chairman of the Subcommittee and consultant to the New Jersey State Society of Anesthesiologists; Mr. Fred Evans, President, Medical Gas A4anagenient, Mr. Tom Nagle, Senice Marketing Manager, Ohmeda, Wison, W7, Todd Peterson, M.D., Department of Anesthesiology, University of Arizona; and (not pictured here) Joseph Pepper, Ph.D., President, Medical Systems Division, Ohmeda, Liberty Corner, NJ. The elaborate and thought-provoking exhibit was titled 'Look Beyond the Walls' and demonstrated real-life examples of an amazing and comprehensive array of problems that can occur usually unnoticed until critical - with medical gas systems. In the foreground is a dead bird that was trapped in the air inlet of a compressor, causing afoul odor in the medical air system of that facility.
Pierce Award Winners: The other of the 1994 Ellison
C. Pierce Awards given by the APSF at the ASA Annual Meeting for the best
exhibit(s) related to anesthesia patient safety went to Robert A. Berman,
M.D., an anesthesiologist from Denver, CO, shown here seated on the left
with his son, Jonathan C. Berman, M.D., also an anesthesiologist. Dr. Berman's
exhibit was titled "History of Airway Management: One Man's Perspective'
and it chronicled many developments 0 devices and technizues promoting
safe airway management,
"Look. Beyond the Walls" Award winning exhibit
on contaminated gas pipelines Pgs. 45 and 47.
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The Anesthesia Patient Safety Foundation Newsletter is the official publication of the nonprofit Anesthesia Patient Safety Foundation and is published quarterly at Overland Park, Kansas. Annual membership: Individual $25.00, Corporate $500.00. This and any additional contributions to the Foundation are tax deductible. Copyright, Anesthesia Patient Safety Foundation, 1995
The opinions expressed in this newsletter are not necessarily those of the Anesthesia Patient Safety Foundation or its members or board of directors. Validity of opinions presented, drug dosages, accuracy and completeness of content are not guaranteed by the APSF.
APSF Executive Committee:
Ellison C. Pierce Jr., M.D., President; Burton A. Dole, Jr., Vice-President; David M. Gaba, M.D., Secretary; Casey D. Blitt, M.D., Treasurer; E.S Siker, M.D.; Executive Director; Robert C. Black; Robert A. Caplan, M.D.; Jeffrey B. Cooper, Ph.D.; Joachim S. Gravenstein, M.D.; W. Dekle Rountree, Jr.
Newsletter Editorial Board:
John H. Eichhom, M.D., Editor; David E. Lees, M.D. and Gerald L. Zeitlin, M.D., Associate Editors; Stanley J. Aukburg, M.D., Jan Ehrenwerth, M.D., Ralph A. Epstein, M.D., Nancy Gondringer, C.R.N.A., Robert C. Morell, M.D. Jeffrey S. Vender, M. D.
Editorial Assistant: Nola Gibson, Ph.D.
Address all general, membership, and subscription correspondence to:
Anesthesia Patient Safety Foundation
c/o Mercy Hospital
1400 Locust Street
Pittsburgh, PA 15219
Address Newsletter editorial comments, questions, letters, and suggestions to:
John H. Eichhorn M.D.
Editor, APSF Newsletter
Department of Anesthesiology
University of Mississippi Medical Center
2500 North State Street
Jackson, MS 39216-4505
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