Safety Becomes Major ASA Meeting Topic
In Scientific Sessions 100 + Papers:
Editorial: APSF Grows, Expands Scope, Continues Mission
Ellison C. Pierce, Jr. Award Winner Announced
Strategy Outlined to Avoid Hypoventilation
APSF Grant Program Supports Clinical Research
Previously Funded APSF Grants
Simulation Takes Washington By Storm
FDA Continues Support of Anesthesiology Community
Letter to the Editor:
by John H. Eichhorn, M.D.
Technical and scientific exhibits at the October ASA annual meet" in New Orleans featured many products and ideas intended to help promote safety in anesthesia practice.
Manufacturers of anesthesia machines, monitoring systems and automated anesthesia record devices all focused on operating room anesthesia data management system. Various companies now offer integrated systems that collect all the patient and machine monitor data into a central display and alarm panel.
These centralized, integrated systems were developed in response to the long-held belief that the data read-out and alarm messages from up to as many as eight or ten separate devices in various locations around the anesthesia work station can be confusing and distracting. With the new technology, monitoring information is displayed in one central area along with a unified alarm that identifies immediately for the user which device is sounding an alarm and what alarm threshold has been exceeded.
The intention is to provide a total package of the clearest possible information in the most easily accessible format to the clinician doing the case. The implication is that this will help optimize safe anesthesia care by both promoting vigilance and reducing delay in analysis of untoward developments. At this time, no emphasis was placed on the possibility of remote access to the same centralized information package by supervisors and/or teachers.
Instruments capable of monitoring the concentration of volatile anesthetics (usually inspired but some both inspired and expired) were prominently displayed by many manufacturers. Suggestions of potentially safer anesthetic practice through the use of these devices were made by many salespersons. However, inquiries regarding both the mechanism of this enhanced safety and related supporting arguments yielded very little information.
A "closed-system" simple auto-transfusion device for relatively small quantities of blood (two-three units) was displayed. The intention is that this would be used in moderate blood-loss cases for which it would not now be considered worthwhile to set up a U-scale blood retrieval, washing and reinfusion system. The goal is not only avoidance of bank blood but also repletion of volume with autologous blood in patients unlikely under usual circumstances to receive transfusions, potentially improving hemodynamics and recovery.
Once again, 31 companies offered pulse oximeters for sale. There were some new configurations and combinations, but few changes in the basic technology. There was one new instrument containing skin surface pulse oximetry and capnography. Another new capnograph, not yet available for purchase, measures C02 via acoustic wave changes at a surface coated with a special polymer that reversibly binds C02. This technology could support either mainstream or side stream measurements.
For measuring real-time continuous wave form noninvasive blood pressure, a new technology derives arterial pressure from an initial traditional calibration followed by measurements from sensors evaluating the arrival of the pulse wave at the finger and forehead. An apnea monitor intended for use, for example, with any of the many PCA pumps shown in the exhibits employs sensors under the mattress of a regular hospital bed evaluating the patients motion for the rhythmicity of normal breathing.
Among the scientific exhibits (NOTE: see related stories about Pierce Award winners Page 38 and about FDA sponsored material Page 47) there were several safety-related themes. Computer-driven simulator/trainers were again featured, revealing advances in these technologies since last year. Several presentations dealt with optimizing airway management. There was an exhibit on the early detection of air emboli. An exhibit from the Netherlands promoted performance of preanesthetic checklist procedures in a manner analogous to an airliner pilot and co-pilot in a cockpit preparing for take-off. A major exhibit realistically demonstrated electrical hazards and how to increase patient electrical safety in the OR. Finally, exhibits demonstrating a variety of anesthesia quality assurance systems were featured and attracted great interest.
Dr. Eichhorn, Harvard Medical School and Beth Isreal Hospital, Boston, is Editor of the APSF Newsletter.
Back to Table of Contents
by David L. Dull, M.D., John H. Eichhorn, M.D., Daniel P. Nyhan, M.D., Fredrick K. Orkin, M.D. and Howard A. Schwid, M.D.
Diversity, scholarship and clinical relevance characterized the scientific presentations in the Patient Safety, Epidemiology and Education sessions at the 1989 annual meeting of the American Society of Anesthesiologists in New Orleans. There were over 100 presentations in six sessions, a remarkable increase in interest in this relatively new area, during the meeting. Salient aspects of selected presentations are provided here.
Drs. P.M. Kempen (University of Pittsburgh) and D.W. Learned (University of Michigan) collaborated to study whether anesthesia practice patterns might be vectors of infection. Underlying their interest is recent documentation that 3.3% of surgical patients suffer unexplained postoperative hepatitis not related to transfusion. The majority of 139 questionnaire respondents routinely or frequently used one syringe to administer drugs in the intravenous infusion of more than one patient; 98% reuse multiple-dose vials opened by unknown per sons, and 75% did not discard such vials after refilling syringes used in the care of multiple patients. Similarly, a majority of respondents do not clean laryngoscope blades in accordance with guidelines issued by the federal Centers for Disease Control. The investigators speculate that such practices may contribute to the spread of nosocomial viral infection such as hepatitis.
Dr. A.D. Rosenberg and colleagues (Hospital for joint Diseases, New York) surveyed attendees at a major anesthesia meeting for similar infection related perceptions and practices: 60% of respondents reused syringes in the care of several patients, even though 80% believe that a needle inserted into an intravenous infusion port can become contaminated. Although aware of the AIDS and hepatitis hazards, a majority of anesthesiologists had not obtained hepatitis B vaccination and failed to wear gloves and eye protection. The authors concluded that, even though anesthesiologists are aware of infection hazards, many do not implement protective measures for themselves or their patients.
Dr. S. Roth (University of Chicago) reported on adverse cardiopulmonary sequelae to the administration of OKT3, a monoclonal antibody used to prevent or manage renal transplant rejection. Although seizures, fever, tachycardia and hypotension have been reported in awake patients, there have been no reports of side effects in anesthetized patients. In 25 patients, they noted adverse responses in four: two developed severe bradycardia or hypotension; two other patients developed desaturation up to an hour after administration, requiring low levels of PEEP. High dosage of OKT3, concomitant administration of drugs reducing myocardial contractility, and hypovolemia may be risk factors for development of severe responses to OKT3.
Dr. U. Adourian (The Johns Hopkins University) reported on a study of the immunoreactivity of four commercial preparations of prolamine, prompted by an interest in determining whether they differed in their propensity to cause actual allergic reactions. Using the sera of patients who were known to have experienced life-threatening reactions to prolamine, no differences were found. Thus, there is no apparent advantage to using any particular preparation when reversing heparin anticoagulation.
Dr. S. Aubas (Hospital Lapeyronie, France) reviewed 186 cardiac arrests occurring among 102,468 anesthetics in a university hospital. Of these, 1 5 7 cardiac arrests were deemed unrelated to anesthetic management, with 144 deaths due largely to hemorrhage, ventricular failure after cardiopulmonary bypass and multiple organ failure. Of the 29 cardiac arrests related to anesthetic management, 14 occurred during induction (2 deaths), 14 during maintenance (8 deaths), and one during immediate postoperative recovery (death). Causes of these cardiac arrests included absolute or relative anesthetic overdosage, some with associated hypovolemia, hypoxemia and multiple etiologies. The 11 deaths related to anesthetic management involved multiple etiologies (5 cases), myocardial ischemia (3), dysrhythmia (1), hypoxemia (1), and relative overdosage (1). Cardiac arrest during regional anesthesia had a higher incidence but better outcome than during general anesthesia
ASA Closed Claims
Dr. H.S. Chadwick (University of Washington) presented the obstetric subset from the ASA Closed Claim study, a review of 1455 (thus far) claims of medical malpractice relating to anesthesia care157 (11%) of the claims related to Cesarean section or vaginal delivery, with two-thirds of the cases involving the former. Despite the use of regional anesthesia in 66% (77% of vaginal delivery, 61 % of Cesarean section), respiratory problems predominated: pulmonary aspiration in 6% (10% of vaginal delivery, 5% of Cesarean section) compared to only 2% in the non-obstetric claims. Injuries covered a wide range, including headache, pain during anesthesia, seizure, newborn brain damage and maternal death. Payments were made in 5 1 % of claims, with a median payment of $225,000, compared to 58% of non-obstetric claims with a median payment of $80,000.
Dr. D.A. Kroll and others from the University of Washington examined the incidence of nerve injury among the cases in the ASA Closed Claims Study. Ulnar nerve injuries during general anesthesia were, by far, the most common problem seen. Two thirds of the-se were associated with malpositioning of the arm. Nearly even at second and third on the list were femoral/sciatic injuries associated with regional anesthesia and brachial plexus injuries (appearing in about a 2:1 ratio of general to regional anesthetics). The median and radial nerves were the other identified sites of injury. The authors commented that often the standard of care had been met and the injury was a poor outcome not involving negligence. Also, there was a tendency for late reporting so that many injuries were not identified until more than one week after the anesthetic.
Dr. M. Fischler and colleagues from France discussed the safety of using intramuscular midazolam in a relatively high dose (0. I mg/kg) as a premedication prior to retrobulbar block for ophthalmic surgery. There was minor but statistically significant hemodynamic depression and frequent but brief oxygen desaturation (never below 85% but 8 of 69 between 85 and 90%). Routine pulse oximetry in these patients was recommended.
Gastric acid aspiration prophylaxis received attention. Dr. B.R. Jacobs et.al. from Yale suggested administrating controlled-release metoclopromide was a valuable therapy. The H-2 blocker famotidine was shown effective in reducing acid by Dr. B. P. Capehart from Texas Southwestern Medical Center and Dr. E.A.M. Faure from the University of Chicago suggested that, in an emergency, the sodium bicarbonate solution intended for IV injection can be given PO as an effective short-term acid neutralizing measure.
Confirmation of the value of inspection of the hypopharynx as a means to predict difficult intubations was presented by Dr. S.M. Cohen (Michael Reese Medical Center). Preoperatively, patients were given one of three classifications according to the ability to see tonsillar pillars and uvula. These classes correlated directly with the degree of difficulty of laryngoscopy and the frequency of difficult intubation. It was suggested that this simple test is the stronger predictor of potential problems.
Dr. T. Pederman of the University of Copenhagen reported on the risk of death associated with anesthesia and surgery in a study of 7306 consecutive patients undergoing non-cardiac surgery. The overall in-hospital mortality was 1.2%, but was as high as 76% for emergency gastrointestinal surgery in elderly patients with chronic heart failure and renal failure. Only one in twenty deaths occurred during anesthesia and the remainder were due to progression of the underlying illness.
Dr. M. Pine (University of Chicago) presented a risk model that effectively separates patients into risk categories. The risk model uses a limited number of risk factors including age, emergency status, ASA classification, and NYHA class. The risk category can be used to estimate prognosis and monitor the outcomes of care within an institution.
Dr. L.M. Borland described the Quality Assessment system implemented at the Children's Hospital of Pittsburgh. Preoperative, intraoperative and follow-up information are entered into a microcomputer for analysis with commercially available database management software. This quality assessment system will delineate types and frequency of anesthesia-related problems in children. Post-op vomiting, hypoxia, laryngospasm and post-intubation croup were the most common events identified. It is suggested this system could be adopted by other institutions for the evaluation of pediatric anesthesia care.
Dr. J.N. Cashman from Guy's Hospital in London reported his study of the effect of sleep deprivation on mood and cognitive performance. Residents evaluated after having less than four hours of continuous sleep on a call night reported a subjective feeling of fatigue and clumsiness, and did have some impairment of memory, concentration, dexterity and reaction time demonstrated by objective testing, but the differences were not statistically significant.
Dr. J.L. Lichtor (University of Chicago) also presented a study of the effect of sleep deprivation, reporting impairment of auditory, visual, and divided reaction times and coordination, although only auditory reaction time was significantly impaired. Interestingly, the magnitude of change on all tests was identical to that seen in a group of volunteers with a blood alcohol level of 0.05%.
There were two abstracts presented concerning the use of anesthesia simulators. The first was by Dr. H.A. Schwid (University of Washington). This simulator models cardiac and respiratory physiology and a variety of drugs used in anesthesia on a computer. The study asked two questions: is this system a useful teaching tool and is the system user friendly? Based on interviews with subjects, the authors concluded the simulator was a valid teaching tool, predictive of responses in the operating room. Because the simulator required usually less than 20 minutes to learn, it was judged user friendly.
The second abstract was presented by Mr. A. DeAnda (a medical student working with Dr. D.M. Gaba of Stanford University). It examined the role of human error as a source of anesthetic mishaps, using an anesthesia simulator. 88% of the unplanned mishaps (mishaps occurring during the simulation, but not part of the original simulation plan) resulted from human error and that most were either due to incorrect monitor usage or inappropriate allocation of the anesthesiologist's attention. (During which the anesthesiologist's attention was diverted from the main problem by a secondary distraction, usually one of the monitors.)
Dr. F. Rhoton (Case Western Reserve) investigated the distribution of critical incidents among anesthesia residents during their first year of anesthesia training at five anesthesia training programs. These investigators demonstrated that the frequency of critical incidents peaked during the months of October and November. They also demonstrated that a small fraction of the residents, 15.5%, were responsible for 58.6% of all critical incidents that occurred. This is an ongoing project with the ultimate goal being to identify patterns of performance that lead to problems and effective means of modifying these patterns.
Dr. I. Moyers (University of Iowa) studied the development of clinical signs of hypoxia during normocapnia in a swine model. During slow incremental decreases in the FiO2 heart rate and blood pressure did not change until PAO2<20 mmHg. The findings reinforce the need to monitor FiO2 and SaO2 during anesthesia. Dr. J.T. Moller (University of Copenhagen) dealt with the incidence of hypoxia in the recovery room. 55% of patients developed at least one hypoxemic episode, defined as a SaO2 of less than 90% for greater than 20 seconds, while in the recovery room and that 22% of patients were hypoxemic at time of discharge from the recovery room. The authors are currently investigating the association between perioperative hypoxemia and morbidity in a multi-institutional study. Dr. I.B. Gross (University of Pennsylvania) concerned the efficacy of supplemental oxygen in preventing hypoxemia during sedation with midazolam and meperidine. Application of oxygen by nasal cannula significantly decreased the incidence and duration of hypoxia in the patients studied.
Dr. E.D. Kharasch (University of Washington) presented data indicating that there is a stress-related significant decrease in serum potassium concentrations in the immediate pre-induction period. These investigators demonstrated an average decrease in the immediate preinduction potassium concentration of 0.8 mEq./L. compared to potassium concentrations measured one-to-two days preoperatively. Almost 50% of the patients previously normokalemic would have been considered hypokalemic by traditional criteria at the time of induction. Accordingly, the authors suggest observation of such values does not warrant either potassium administration or postponement of surgery.
Dr. R. Christopherson (Johns Hopkins) and Dr. G. McCloskey (Yale) both presented papers relating to cardiovascular management and morbidity/mortality in the perioperative period. Dr. Christopherson looked at the incidence of intra and postoperative tachycardia in patients undergoing lower limb major vascular surgery who were randomized to either epidural or general anesthesia. This study was motivate-d by the premise that tachycardia is a major determinant of myocardial oxygen supply and may significantly and adversely alter patient outcome. A rigorous protocol was utilized to quantitate duration of tachycardia in each group. Moreover, a uniform approach to treating tachycardia was utilized. The authors demonstrated that tachycardia occurred more frequently postoperatively than intraoperatively in both the epidural and general anesthesia patient groups, and that the frequency of tachycardia was similar in both groups.
In a retrospective study, Dr. McCloskey looked at the incidence of unscheduled postoperative ICU admissions for evaluation of potential perioperative myocardial infarction. During this study, 53 patients out of 15,030 were evaluated to rule out myocardial infarction. Four patients sustained myocardial infarction and two of these died within 48 hours. Only the presence of postoperative angina was a significant predictor of myocardial infarction. Seventy percent of the cardiovascular events that resulted in admission to the ICU occurred in the PACU. This is consistent with the previously cited observation. Further, the authors concluded that transfer to the ICU too rule out an MI due to mild hemodynamic instability is not cost effective. They suggest that patients developing an MI can be readily distinguished based on the magnitude of the hemodynamic compromise and the presence of greater than 1 mm ST segment depression.
Influence of Technique
Two separate papers examined the influence of regional vs. general anesthesia in two different settings. In a paper by Dr. J.H. McIsaac from Hartford Hospital the influence of the type of anesthesia [epidural vs. general vs. combined epidural-general] on intraoperative blood loss, intra and postoperative blood transfusions, and length of hospital stay were examined in patients who were undergoing radical prostatectomy. intraoperative blood loss and the associated necessity for both intra and post-operative blood transfusions was significantly increased in those patients who had general anesthesia as opposed to those who had either epidural alone or combined epidural with fight general anesthesia. The duration of hospital stay was also significantly longer in patients who received general anesthesia.
In contrast, in a study by Dr. B. Kim from Yale, the type of anesthesia employed [regional vs. general] did not influence outcome in patients who were undergoing hip fracture pinning. This also was a retrospective study but the end points monitored were outcome events rather than physiological parameters. Outcome parameters similar in both groups included significant cardiovascular morbidity (cardiac failure, myocardial infarction and angina) respiratory complications and the development of deep venous thrombosis.
Dr. G. Bashein from the University of Washington examined the influence of aspirin ingestion within seven days of surgery on the incidence of reoperation for bleeding after coronary artery bypass grafting. In this retrospective case control study, the investigators demonstrated that aspirin ingestion was associated with significantly increased risk of reoperation with an estimated odds ratio of 1.82. The aspirin patients had the anticipated significantly longer ICU stays and longer post-operative hospital course than did the controls. It was suggested that in an individual patient the presence of apparently normal platelet count and bleeding time does not necessarily prevent the increased risk associated with recent aspirin ingestion.
Drs. Dull (University of Iowa), Eichhorn (Harvard), Nyhan
(Johns Hopkins), Orkin (University of California, San Francisco), and Schwid
(University of Washington) moderated scientific sessions on patient safety
and epidemiology at the ASA.
Back to Table of Contents
In September, the Anesthesia Patient Safety Foundation turned four; this year has been a good one. The number of anesthesiologists who checked off their Foundation membership on the ASA dues statement exceeded 4,000, reducing the ASA original $100,000 guarantee to zero now. In addition, other regular members and corporate members have increased. The Parker B. Francis Foundation starter grant of $ 1 00,000 annually for three years was extended for a final fourth year; this funding has, of course, contributed very significantly to the initial success and financial stability. Foundation members should be aware of industry support, as noted each quarter in the Newsletter. Yearly, regular members receive membership certificates and corporate members receive plaques to place on their booths at the ASA Annual Meeting.
The size of the Board of Directors has been increased from 30 to 40, with the following among the new members: C. Rollins Hanlon, M.D. Executive Consultant of the American College of Surgeons; C. Raymond Larkin Jr., President and Chief Operating Officer of Nellcor, Inc.; Jeffrey J. Langan, General Manager, Clinical Systems Business Unit, Hewlett Packard; Jeffrey M. Beutler, M.S., C.R.N.A., Deputy Executive Director, American Association of Nurse Anesthetists; Nancy Gondringer, M.A., C.R.N.A.; Casey 0. Blitt, M.D.; Robert A. Caplan, M.D.; John H. Eichhorn, M.D.; David M. Gaba, M.D.; and Alan D. Sessier, M.D. The complete Board and committee membership will be published in the March APSF Newsletter.
For the fourth consecutive year, three significant grants for patient safety research have been awarded, as noted elsewhere in the Newsletter. It should be recognized that during these four years, the number of scientific papers presented at the ASA Annual Meeting in the areas of patient safety, epidemiology and education increased dramatically, to well over 100 this past October. The Foundation has organized three symposia examining the role of the use of simulators in anesthesia resident teaching and training. As announced in this issue, awards for the best scientific exhibits on patient safety at the ASA Annual Meeting were given.
Interest overseas continues to grow; the Foundation has developed plans to invite each year an anesthesiologist from a less advantaged country to visit the USA as an APSF Visiting Professor, probably at the time of the ASA Annual Meeting.
Lastly, of considerable significance is the current debate as to whether or not anesthesia morbidity or mortality have improved dramatically in recent years and, if they have, why? 1,2 There, however, appears no doubt that in the USA anesthesiologists' medical malpractice insurance premiums are leveling off or declining, with the fall in award costs and consequent reduction in risk relativity factors for anesthesioloSists.3 Certainly all of us are pleased with these occurrences.
The Foundation Executive Committee and Board of Directors urge all practitioners of anesthesia to become members and supporters of the Foundation.
Ellison C. Pierce, Jr., M.D. President, APSF
1. Eichhorn, JH: Prevention of intraoperative anesthesia accidents and related severe injury through safety monitoring. Anesthesiology, 1989;70:572.577.
2. Orkin FK: Practice standards: the Midas touch or the emperor's new clothes? Anesthesiology. 1989;70:567-57 1. 3. Pierce EC: Introduction. In Pierce EC Jr. (ed.) Risk Management in Anesthesia. Inter Anesthesiol Clin. 1989;27(3): 133-136.
Back to Table of Contents
The Anesthesia Patient Safety Foundation announced, at the conclusion of the ASA Annual Meeting, the selection of James T. Roberts, M.D. and co-authors from the Department of Anesthesia at Massachusetts General Hospital as the recipients of the Ellison C. Pierce, Jr. Award for 1989.
The award was made for their Scientific Exhibit titled "Three New Approaches to Safer Airway Management." The award consists of a $500 prize to the authors and a Certificate of Recognition to the sponsoring institution.
The Ellison C. Pierce, Jr. Award is presented periodically to the exhibitor and sponsor of the Scientific Exhibit at the ASA Annual Meeting that best demonstrates new and effective methods of safe anesthesia practices.
The 1989 runner-up was N. Ty Smith, M.D. and co-authors
from San Diego for their Scientific Exhibit titled "Sleeper-A Computer
Based Anesthetic Trainer".
Back to Table of Contents
by Beverly Nichols, CRNA, B.S.
During inhalation anesthesia, the patient's airway is connected to a breathing system through which gases are delivered and eliminated. In addition to these functions, most anesthesia systems are capable of positive pressure ventilation of the patient's lungs. It is well known that inadequate or inappropriate ventilation during anesthesia has been responsible for many mishaps. How to avoid inappropriate ventilation, including the avoidance of delivering gases with inappropriately low FiO2, is the subject of this discussion.
Current models of anesthesia machines and ventilators incorporate many features specifically designed to optimize their saw. Due to budgetary constraints faced by most institutions, many anesthesia practitioners do not have the luxury of frequently replacing all their old equipment with newer systems incorporating new safety features. We must strive, therefore, to make our existing anesthesia machines and delivery systems as safe as budget and design will allow. This can be achieved by always monitoring the performance of the equipment and sometimes by modifying it. Where neither can satisfy safety requirements, a machine or ventilator must be replaced.
The following are features of anesthesia machines and delivery systems that deserve attention:
1. Standing Ventilator Bellows
Older anesthesia ventilators were equipped with bellows that ascend during inspiration. The bellows are weighted to ensure descent and filling during expiration. When disconnected from the patient, the ventilator's weighted bellows will fall and aspirate air, and it will continue to function, aspirating and delivering room air. Listening to the ventilator or monitoring inspiratory or even expiratory tidal volume will not reveal a disconnection of the ventilator from the patient. Some ventilators have pressure alarms that are activated when a predetermined pressure-for instance, 8 cm of water-is not reached during inspiration. However, this pressure may be reached during inspiration even after disconnections depending on the size and location of the leak, the inspiratory flow rate, and the tidal volume set. In some systems, the low pressure alarm limits can be adjusted. It is important in these systems to set the alarm threshold * below peak inspiratory pressure (the highest setting that fails to activate the alarm during normal mechanical ventilation).
Because, after a disconnection, the ventilator with an ascending (hanging) bellows (see Figure 1) will continue to move up and down and because a low pressure alarm may not he triggered, it is essential that the patient's ventilation be monitored by auscultation (pretracheal, precordial or esophageal), inspection of chest excursion and capnography. The standing bellows (rising on exhalation) on modem ventilators will function only if the patient exhales into the bellows via a correctly connected breathing system, causing the bellows to ascend. Usually, if there is a disconnection, the bellows will not function. However, the clinician must be aware that partial obstruction of disconnected tubing and high fresh gas flow can cause the bellows to rise.
Figure 1: Circle breathing system and ventilator shown late in expiration with the expiratory valve still open. Top: Hanging Bellows Ventilator. In a disconnection, the weighted bellows will have aspirated ambient air. The APL ("pop-off") valve is positioned as found in many older anesthesia machines. The valve must be closed when the ventilator is in use. Bottom: Standing Bellows Ventilator. 'Me bellows will not rise in a disconnection, as the bellows will not fill spontaneously. The APL valve is positioned as found in many modem anesthesia machines. The valve need not be closed when the ventilator is in use.
2. Bag Pop-off */ventilator Selector Valve.
*The "pop-off" valve is formally called the adjustable pressure limiting (APL) valve.
Equipment with this selector switch locks out the bag and pop-off valve when the switch is turned to the ventilator mode (figure 1, bottom). In machines lacking the device, the practitioner must remember to close the pop-off valve when connections the patient to the ventilator (Figure 1, top). Otherwise, part of the tidal volume likely will be delivered to the ambient air (or scavenging system) instead of to the patient. Monitoring peak inspiratory pressure and expired tidal volume help in detecting such a leak through the open pop-off valve. Captio8raphy and eventually pulse oximetry will also reveal the effects of inadequate ventilation due to a leak through the open pop-off valve.
3. Locking Common Gas Outlet
A locking connection at the anesthesia machine outlet prevents the unintentional disconnection of the fresh gas delivery hose from the machine. Depending on circumstances, a partial disconnection here will decrease the delivery of fresh gas to the breathing system below the volume set on the flow meters on the anesthesia machine. This can set the stage for a progressive decrease in FiO2, as the patient may consume more oxygen than is supplied in the partially diverted fresh gas flow. Monitoring FiO2 with an oxygen analyzer and pressure in the breathing circuit are essential safety measures to guard against this unusual but potentially devastating development. As with other disconnects, a disconnection between anesthesia machine and common gas outlet creates a huge breathing system leak.
4. Breathing System Pressure Monitor
During manual positive pressure ventilation, partial or complete obstruction of the airway or breathing system components can be detected by the feet of the breathing bag upon compression. With mechanical ventilation, the clinician must rely on a pressure gauge to detect excessive pressures. In older machines, a mechanical manometer (the Bourdon gauge) was employed. The clinician has to inspect mechanical gauges frequently in order to detect unusual pressures. Modern equipment employs solid state electronic pressure monitors with an audible alarm in case of sustained, excessively high, or inappropriately low peak pressures in the breathing circuit.
5. Valve Function in Circle Systems
The unidirectional valves in the inspiratory and expiratory limb of a breathing circle system prevent rebreathing. Inspection of the valve leaflets during ventilation ran detect some valve malfunc6ons. Difficult to see are malfunctions caused by a warped valve disc. Spirometry in the circle system helps monitor valve function. If the inspiratory valve becomes incompetent, some of the expired volume returns into the inspiratory limb of the breathing circle; the expired tidal volume, therefore, is reduced. A spirometer in the expired limb will help diagnose an incompetent inspiratory valve. When the expiratory valve malfunctions, gas flow in the expiratory limb becomes bi-directional; a bi-directional flow meter will reveal this evidence of an incompetent expiratory valve as reverse flow. Typical capnograms for valve malfunctions are shown in Figures 2 and 3.
6. Scavenger Connections
In older anesthesia machines, it was possible to connect mistakenly the scavenging system to the breathing circuit. With such misconnection, catastrophe will result because the patient cannot inhale or exhale. Sensing the pressure in the breathing circuit with monitors armed with appropriate low (subatmospheric) and high alarms and monitoring and expired tidal volume will help provide an early alert to this rare but very serious error.
Modem anesthesia machines are standardized so that all connections of the breathing circuit are either 15 mm or 22 mm and the scavenging fittings are 19 nun or a diameter index safety system (DISS). Accordingly, the dissimilarities of the fittings make incorrect connections much more difficult.
7. Diameter Index Safety System
In years gone by, it was possible to connect oxygen or nitrous oxide from the central supply to either the nitrous oxide or oxygen system of the anesthesia machine. Male/female connectors that are specific for each gas, the DISS, reduce the hazard of having nitrous oxide piped into the oxygen flow meter of the anesthesia machine. However, even this safeguard does not rule out the possibility of accidental crossing of gas pipelines, for instance during renovation or maintenance in the hospital in which gas pipelines must be manipulated. Therefore it is essential and now universally recognized that the oxygen concentration must be monitored in the breathing circuit of the patient, usually in the inspired side. With rapidly responding oxygen analyzers, both inspired and expired oxygen can be monitored.
8. The Pin Index Safety System
The pin index safety system is to gas cylinders what the diameter index safety system is to pipes carrying compressed gases. It assures that only an oxygen cylinder can be attached to the oxygen yoke, a nitrous oxide cylinder connected to the nitrous oxide yoke, and so on. This is accomplished by two pins on the anesthesia machine that match with holes on the cylinder. Unfortunately, when one pin falls out or when several washers instead of a single one are used, the pin index system can be defeated. Therefore, the oxygen monitor in the breathing system provides an essential backup safety feature.
Valves PEEP valves can be added to any machine utilizing 22 mm fittings. Some PEEP valves are unidirectional and therefore, when placed inappropriately in the inspiratory limb, can obstruct flow entirely. Several deaths have been linked to this. Monitoring pressure in the breathing system, monitoring expired tidal volume and the capnogram, and carefully observing the patient's ventilation will help prevent the inappropriate placement of PEEP valves. Manufacturers have incorporated PEEP valves into modem anesthesia machines, thereby making it difficult to place them incorrectly. Note, however, that some of these integral PEEP valves can be hard to read and are easily accidentally left "on" from one patient to the next and this may be dangerous.
10. The C02 Absorber Bypass Switch
On older anesthesia machines, it was possible to bypass the carbon dioxide absorber in order to increase the patient's alveolar PC02When the bypass was unintentially turned on, or when the clinician failed to turn it off, patients developed severe hypercarbia. Monitoring carbon dioxide in the breathing system will help to prevent this occurrence.
Modem anesthesia machines no longer carry a bypass switch for the carbon dioxide absorbent. Presented here are comments and suggestions regarding ten features of older anesthesia delivery systems. AN can he involved with inadequate ventilation under anesthesia. Attention to the points outlined here should help eliminate accidents associated with these older configurations.
Ms. Nichols is Chief Nurse Anesthetist, Department of Anesthesiology, University of Texas, Health Science Center at Houston.
Editor's note: Letters to the editor on this topic of
older anesthesia equipment are welcome and will be considered for publication
in a future issue.
REVERSE FLOW OCCURS IN THE INSPIRATORY HOSE
Figure 2: Capnograms with normal valve function (top) and with a detective inspiratory valve (middle and bottom). End-tidal values were increased in the latter two. In the middle panel the volume of gas deposited into the inspiratory hose during expiration was smaller than the next inspiratory volume. Therefore, the capnogram eventually reached the baseline. In the bottom figure, the inspired volume was not large enough to replace all carbon dioxide-containing expired gas, and the capnogram could not reach baseline. A sloping descending limb of the capnogram is typical for an incompetent inspiratory valve.
Figure 3: With an incompetent expiratory valve,
endtidal values increase, and inspiratory values do not return to baseline.
The same picture is seen when the carbon dioxide (CO2) absorber is exhausted.
However, increasing fresh gas flow lowers both end-tidal and inspired values
when the C02 absorber is exhausted, but not when the expiratory valve is
Back to Table of Contents
by Jeffery B. Cooper, Ph.D.
The APSF has provided support for 11 research projects over the past three years. These were selected from 86 applications reviewed by the Scientific Evaluation Committee. What is the process by which the grants are selected? What kinds of projects have we sponsored? What issues are targeted in the applications? What has been the product of our efforts?
The Scientific Evaluation committee is composed of nine members. Each reviews every application, writes a brief critique, and assign a priority score. The scores are tabulated and the top group (from 30% to 50% of all applications, depending on the distribution of scores) is ranked a second time with each reviewer having the benefit of the others' critiques (this is important given the diversity of interests of the committee). The top applications are funded depending upon the total funds available. The winners are announced at the annual meeting of the APSF Board of Directors, held on the Friday or Saturday of the Annual Meeting of the ASA. The turn around time is fast; the application deadline is June 15, winners are announced in mid-October and funds are available January 1.
The criteria used in judging applications are stated in the announcement of the grant program. The guidelines for application provided from the APSF administrative office also gives examples of what types of projects may be of interest: new clinical methods for prevention and/or early diagnosis of mishaps, evaluation of new and or re-evaluation of old technologies for prevention and diagnosis, identification of predictors of patients and/or anesthetists at increased risk for mishaps, development of innovative methods for study of low frequency events, and methods for measurement of cost-effectiveness of techniques designed to increase patient safety.
The 86 applications were received from 57 institutions. The proposed topics define what this diverse set of investigators believe constitutes the essence of anesthesia patient safety and can be classified within the following subjects: outcome assessment, monitoring, training, risk assessment, specific injury prevention (study or solution of a defined problem), alarms, simulators, quality assurance, incident study, clinical study, human factors and device development. Most applications have elements involving at least two categories.
Many applications (26) addressed the prevention of injury associated with a specific complication, incident, outcome or clinical problem, e.g., myocardial infarction, disconnection, esophageal intubation, excessive blood loss, awareness, difficult airway, syringe swap. The foci included
development of improved monitoring approach, new device or technique or a method to better predict occurrence of the event. Twenty-one projects involved monitoring, most often assessment of efficacy or effectiveness in general or for some specific problem or development of a new or improved modality. Nine projects proposed to attack the ubiquitous problem of alarms, most often how to better integrate them or improve upon the rate of false alarms.
Twenty projects proposed the study of outcome. Many were targeted at specific are-as such as day surgery, pediatrics, the elderly, or a specific anesthetic technique, e.g., spinal anesthesia or operative procedure, e.g., C-section. Also, ten applications proposed some form of study of anesthesia incidents, developing systems to collect them, establishing how often they happen, determining how training can prevent them or studying how clinicians respond to them. Nine projects related to assessment of risk, i.e., predicting when problems or outcomes are more likely to occur, either in general or for specific problems or populations.
Nine applications related to the study or improvement of clinician training or the use of training to prevent a specific problem. Six projects addressed human factors issues, while seven projects dealt with simulators specifically as means to study human factors or training.
Of the 11 applications approved and funded (see Table), two categories of study stand out - outcome study and simulators (five each). Yet, the exact topic of an application was probably not the most important factor in its being selected for funding. Often , other reasons were responsible for applications being downgraded. Many simply were not well written, did not have adequate justification for the study or did not have a sound research plan. Frequently, no hypothesis %,as stated or statistical issues were inadequately appreciated or not sufficiently explained. It is likely that innovation is given more weight in the reviewers' judgments (the concept of simulators has never been specifically mentioned in the list of topics of possible interest to the APSF). Perhaps the best advice that can be given to applicants is to seek the counsel of someone experienced in research and the pursuit of funding.
It is still too early to judge if the APSF research grant program is directed to the right things. The earliest projects we have helped to support have produced, good publications with new and innovative information; witness the work of Cohen et. al., in Manitoba, Gaba, et. al., at Stanford and Schwid in Seattle. Several ongoing project are very promising.
The APSF encourages investigators and inventors to submit their ideas for review. Even if not APSF funded, the effort can be the basis of a search for funds elsewhere, often from a hospital or department. The proposal format is comparatively simple and the turnaround time is relatively fast (efforts will be made to speed up feedback on unsuccessful proposals even sooner next year to hasten the process of improvement and resubmission to another potential funding source). If successfully funded by the APSF, it seems that investigators often set a great deal of additional support from their institutions, perhaps because the approval of the highly critical Committee on Scientific Evaluation indicates that the work is meaningful and scientifically acceptable. In fact, the APSF may be an important mechanism for departments to get outside peer review for patient safety efforts, which have few other sources of support.
The Research Grants Program is seen as one of the more important functions of the APSF. It has clearly stimulated much new thinking about patient safety. While unfortunate that our funding is so limited, it appears to date that the re-sources have been and are being put to good use.
1990 Research Grants Awards
Mark Warner, M.D. , Department of Anesthesiology, Mayo Clinic: Epidemiological Analysis of Perioperative Mortality and Major Morbidity
This project seeks to define predictive risk factors, etiologies and incidence of perioperative mortalities and major morbidities by budding upon the existing Mayo Anesthesia Database and integrating it with the ongoing Rochester Epidemiology Project and other institutional databases. These other databases and extensive, describing the population of the surrounding county, and should provide a set of information rarely available for analysis of anesthesia outcomes.
David Woods, Ph.D., Department of Industrial and Systems Engineering, Ohio State University: Human Performance in Anesthesia: A Corpus of Cases Analyzed Using Cognitive Science Techniques
Dr. Woods will bring his background in cognitive and experimental psychology to the study of human performance in anesthesia. Using descriptions from the Ohio State Department of Anesthesia mortality and morbidity conferences, he will apply a process-tracing methodology derived from cognitive science to trace the flow of information and the activation of knowledge during these events. The project will produce a collection of encoded protocols. This is an exciting opportunity for interdisciplinary study.
Howard Schwid, M.D., Department of Anesthesiology, University of Washington, School of Medicine: Evaluation of Anesthesiologists' Responses to Simulated Critical Incidents Using the Anesthesia Simulator Recorder
Dr. Schwid, previously funded by the APSF Grant Research Program for work on his simulator/recorder, will now use that device to grade skills of one hundred anesthesiologists in managing cases. The study wig help determine how well anesthesiologists are prepared to manage a particular critical incident and examine the relationship between performance and years of experience and retraining.
Dr. Cooper, Mass. General Hospital, Boston, is Chairman
of the APSF Scientific Evaluation Committee
Back to Table of Contents
David M. Gaba, M.D.
Stanford University School of Medicine Veterans Administration Medical Center
Evaluation of Problem Solving Using Realistic Simulations
Marsha Cohen, M.D.
University of Manitoba Canada
Defining Outcomes Associated with Anesthesia: A Pilot Study
Dwayne Westenskow, Ph.D. University of Utah
A Safer Anesthesia Machine Through Model-Based Alarm
Lance Lichtor, M.D.
University of Chicago
The Risk of Surgery and Anesthesia: A Retrospective Analysis
Howard Schwid, M.D.
University of Washington
The Anesthesia Simulator-Recorder: A Device to Quantify Anesthesiologists' Responses to Critical Incidents
Eugene Betts, M.D.
The Children's Hospital of Philadelphia
Evaluation of the Incidence of Oxygen Desaturation, laryngospasm and Bronchospasm in Children with Upper Respiratory Tract Infections Undergoing Anesthesia.
Deborah Kitz, Ph.D.
University of Pennsylvania
The Incidence and Magnitude of Intra-operative Physiologic Changes. A Foundation for Developing Artificial Intelligence Tools
Randall Carpenter, M.D. Virginia Mason Medical Center
Identification of Patients at Risk for Developing Adverse Effects During Spinal Anesthesia
Michael Good, M.D. University of Florida
Can Simulation Teach Clinical Skills?
David Gaba, M.D. Stanford University
A Model Course in Handling intra-operative Critical Incidents: Training and Practice to Prevent Anesthesia Mishaps
Charles Cote, M.D. Massachusetts General Hospital
A Prospective Evaluation of Combined Pulse Oximetry and
Expired Carbon Dioxide Monitoring in Anesthetizing Pediatric Patients
Back to Table of Contents
by Ingrid C. Mellone
On the eve of the Anesthesia Simulator Curriculum Conference in Rockville, Maryland, a gray cloud loomed over the best-laid Anesthesia Patient Safety Foundation and Food and Drug Administration (FDA) plans. Hurricane Hugo had ripped through the Caribbean and was bound for the U.S. mainland. The forecast projected its path through the Washington, D.C. area. But D.C. was spared, and the conference began as planned Saturday, September 23.
Ninety-two exhibitors and educators from the U.S. and Europe convened to explore how Anesthesia Simulators and Training Devices (ASTRADS) could enhance a curriculum for anesthesia personnel. For the last ten years, ASTRADs had existed in isolation at their development sites. No one had ever considered their joint strength as teaching tools.
A subject addressed by all ASTRAD developers to date and important to all anesthesia practitioners is the uptake and distribution of inhaled anesthetics. This was selected as the subject for the model ASTRAI) curriculum. Arthur J.L. Schneider, M.D. of Pennsylvania State University (Hershey) and Arnold 1. Berry, M.D. of Emory University developed the curriculum, which utilizes the potential of each ASTRAD to help the trainee understand uptake and distribution.
Basically, the curriculum follows the aviation industry's use of simulators and training devices. Pilots first acquire skills using training devices that reproduce real phenomena only to the degree needed to teach a specific learning objective. After acquiring many skiffs from various training devices, the student pilot trains on a simulator, which matches the real world in great dew by integrating learned skills and adding the stresses of reality.
Similarly, the uptake and distribution curriculum starts the student with a physical model and, over several steps of increasing complexity, enables him to progress to full anesthesia simulation.
Eight exhibitors described their ASTRADs on Saturday morning. Dwayne R. Westenskow, M.D. from the University of Utah, "An Oil/Water
Model of Uptake and Distribution"; James H. Philip, M.D. of Brigham & Women's Hospital, "An Electronic Model of Induction of Anesthesia"; Maricopa Medical Center's Jerry M. Calkins, M.D., "Interactive Teaching of Uptake and Distribution"; N. Ty Smith, M.D. (University of California, San Diego), "Clinical Problems and Uptake and Distribution Models"; Howard A. Schwid, M.D. of the University of Washington, "Models of Pharmacodynamics of Uptake and Distribution"; Reid M. Rubsamen, M.D. (Massachusetts General Hospital), "A Database of Pathophysiologic Events. What to Expect"; Michael L. Good, M.D. of the University of Florida, "A Simulator with Preprogrammed Events and Explanatory Graphics"; and Stanford University's David M. Gaba, M.D., "A Simulator that Incorporates OR Stress".
On Saturday afternoon, the attendees were divided into groups that visited four different ASTRADs for an hour each. The attending educators saw how well-designed educational plans could be enhanced by incorporating computerized training devices and simulators into curricula.
Four additional investigators spoke about their ASTRADs on Sunday morning: Dr. P. Tonner of the University of Bonn, West Germany, "The Uptake of Volatile Anesthetics as a Scientific Basis for Computer-Controlled inhalational Anesthesia in the Operating Room"; Mauricio C. Leon, M.D. of the University of South Florida, "Pulmonary and Artificial Ventilation Mechanics Simulation"; Rhoda D. Levine, M.D. of Albert Einstein College of Medicine, "Computer-Assisted Instruction in Anesthesia"; and Colin F. Mackenzie, M.B. of the University of Maryland, "Simulation of Trauma Anesthesia".
A lively general discussion followed. Participants examined: different learning styles and their roles in anesthesia instruction; how simulators inherently match certain learning styles; how best to coordinate developmental efforts and 'Set financial support for further research; and how to make ASTRADS, whose designs are unique to each investigator, more universally available and computer compatible.
The curriculum itself and proceedings of the conference are available for $25.00 from Mr. Ken Bower at the APSF office. The FDA's Division of Training Support took advantage of the gathering by videotaping interviews with the exhibitors and demonstrations of the ASTRADS. The resultant material wig be made available through the APSF next year.
The investigators thank the FDA (grant number FD-R-00049M 1) and APSF for sponsoring this meeting, the second of its kind in two years.
Ms. Mellone, Department of Anesthesia, University of Florida,
Gainesville, worked with Dr. I.S. Gravenstein to produce this conference.
Back to Table of Contents
The Food and Drug Administration's (FDA) Center for Devices and Radiological Health (CDRH) presented two exhibits at the recent American Society of Anesthesiologists' annual meeting as part of a continuing effort to support the goal of greater safety in anesthesia.
One of the exhibits was a component part of the cooperative study of pre-operative anesthesia equipment checkout procedures currently being conducted by the George Washington University Department of Anesthesiology and the FDA. This project, discussed in previous Newsletter articles, has been designed to measure the effectiveness of anesthesiologists' equipment checkout and to assess their understanding of anesthesia equipment as well as to determine to what extent the FDA pre-use checklist, published in 1986, is a useful tool in the detection of machine faults.
Considerable thanks are due to the 130 anesthesiologists who contributed to the study by participating in the exercises conducted at the checklist exhibit. These participants will receive their individual results and the overall results win be presented in a journal article that will be submitted for publication.
FDA also cosponsored another scientific exhibit, entitled "Central Venous and Pulmonary Artery Catheters Complications and Avoiding Them." This exhibit was authored by Drs. D. Paulus, R. Virmani, E. Pierce, N. Gravenstein and W. Scott (FDA/CDRH). The exhibit consisted of. (1) presentation of anatomy relative to the placement of CVCs and PA Catheters with a number of anatomic illustrations specifically developed for this purpose; (2) radiographs depicting various catheter-related complications; (3) photographs of the gross pathology of catheter related mishaps; (4) two handouts of published information on catheter complications: "Complications Associated with Central Venous Catheters: a Survey" by Dr. Scott and a generic newsletter article on CVC Complications developed by the CVC-working Group; and (5) actual operating room cases on videotape showing surgical technique-related complications. The exhibit was well received and attended by approximately 500-600 anesthesiologists.
As a follow-up to the cooperative successes at the ASA annual meeting, FDA will investigate several possible educational projects, including the journal article on validation of the checkout procedures and an exhibit highlighting the benefits of improved patient safety. In the CVC area, a videotape on possible complications of their use is being developed. FDA will keep the readers of the Anesthesia Patient Safety Foundation Newsletter informed about progress on these and related activities.
Back to Table of Contents
Care Team Concept Evokes Positive Comments
To the Editor:
Dr. Benjamin H. Gorsky has taken exception to the aviation anesthesia analog and his objection may be correct. However, the central issue is not the appropriate analogy but rather an open forum for our common problem. There are solo-CRNAs and solo anesthesiologists, but, it is my understanding that the CRNA-anesthesiologist team is the most frequently seen professional relationship. Large numbers of these intelligent people continue to voluntarily form this professional structure. This implies that they are meeting their practice and economic needs or some other form of association would replace it. I do not observe any change at this time. I feel that all of us in anesthesia have common ground and common problems deserving of our attention and energies, for example, patient safety and also outside intervention in our practice. nom Bloomquist, CRNA
Anesthesia Technologists and Technicians ... Experienced "Helping Hands"
To the Editor:
I was particularly interested to see in the June, 1989 APSF Newsletter concerns regarding the lack of experienced "helping hands" causing a near accident in the operating room, the lack of an "extra person" to help speed the safe delivery of anesthesia and keep up with productivity, and another look at Anesthesia Assistants as an idea for added safety through the use of retired anesthesiologists.
In response, I would like to emphasize that there are trained "helping hands" for the anesthetist and anesthesiologist-these are professional anesthesia technicians and techologists. I have been an anesthesia technician for 1 3 year; some of my colleagues have even more years of experience, and most of the hospitals in my area consider us vital to competent anesthesia care.
Anesthesia technicians and technologists assist with technical preparations for inducing anesthesia, intubation and airway management, and other facets of high risk cases. At my institution we manage the anesthesia workroom and are responsible for setup, calibration, and troubleshooting all anesthesia equipment; some also operate specialized devices, such as "'cell savers". We provide necessary anesthesia equipment and technical support for all permanent and temporary anesthetizing locations-OR, Labor and Delivery, X-Ray, Cat Scan, Cardiac Cath Lab, and now the MRI scanner. We maintain anesthesia supplies, coordinate equipment acquisition and maintenance, inservice anesthesiology and OR personnel, and help assure quality control by coordinating preventative maintenance and product alerts and recalls. As patient charges pertain to anesthesia equipment, many of us have responsibility for revenue control. We contact vendors, conduct necessary research for capital expenditures and coordinate the purchase of equipment compatible with other hospital departments.
At this time, no formal educational program exists for anesthesia technicians. However, technical organizations supporting these educational needs have been established in California, Colorado, and Washington, and legislation designed to promote professional training and accreditation is being discussed. In California, the California Association of Anesthesia Technologists and Technicians are fortunate to have had an ongoing working relationship with the California Society of Anesthesiologists, one which provides a consistent liason and gives nurturing support.
Recently, the American Society of Anesthesia Technologists and Technicians was formed. We see this as a forum for all technologists and technicians to share experiences, concerns, obtain further education, and establish appropriate certification guidelines. Individually, we see ourselves as responsible guardians of the anesthesia equipment, and essential pairs of experienced "helping hands". We look to the anesthesia community for recognition and support.
Katherine Morgan, Anesthesia Technician President-Elect, Calif. Assoc. of Anesthesia Technologists and Technicians
Back to Table of Contents
The Anesthesia Patient Safety Foundation Newsletter is the official publication of the nonprofit Anesthesia Patient Safety Foundation and is published quarterly in March, June, September, and December 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 Patent Safety Foundation, 1988.
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; W. Dekle Rountree Jr., Vice-President; E.S. Siker, M.D., Secretary; Burton A. Dole, Jr., Treasurer; Jeffrey B. Cooper, Ph.D.; Joachim S. Gavenstein, M.D.; James E Holzer, J.D.
Newsletter Editorial Board: John H. Eichhorn, M.D., Stanley J. Aukburg, M.D., Jeffrey M. Beutler, C.R.N.A., M.S., Ralph A. Epstein, M.D., David E. Lees, M.D., Bernard V. Wetchler, M.D., Mr. Mark D. Wood
Address all general, membership, and subscription correspondence to:
Administrator Anesthesia Patient Safety Foundation
515 Busse Highway
Park Ridge, IL 60068
Address Newsletter editorial comments, questions, letter, and suggestions to:
John H. Eichhorn, M.D. Editor, APSF Newsletter; Dept. Anesthesia
Beth Israel Hospital, DA-7 1 7 Boston, MA 02215
Back to Table of Contents