Patient Safety Theme at ASA Meeting Echoed in Exhibits

Patient safety was featured as a significant elemental theme of the entire American Society of Anesthesiologists (ASA) Annual Meeting in October in San Francisco. Both the Scientific and the Commercial Exhibits at the meeting also contained strong safety components. New and recurrent patient safety concerns were presented throughout the Exhibits along with proposed technical and educational safety improvement strategies.

Scientific Exhibits Span Wide Spectrum of Safety Topics

High-fidelity simulator training as a teaching tool and a mechanism for practice improvement has often figured prominently in patient safety programs. This year’s APSF E.C. Pierce Award winner for the best safety-related scientific exhibit went to a team from the University of Florida for a new and remarkable tool to teach placement of thoracic epidural catheters and blocks. A spine fabricated by 3-D printing from actual patient CT scans was encased in gel, giving a soft-tissue model that provides a realistic-feeling “back” for the simulated block placement. There is continuous ultrasound going and the Tuohy needle has trackers in it so that a high-resolution 3-D virtual image of both the anatomy and the needle path are together displayed on a large video screen in real time above the mannequin. The computer-controlled image can be rotated and angled to show multiple views and orientations, allowing the “student” to see and understand anatomic features of this block placement in ways not before possible, with the goal of rapid and maximally safe mastery of this challenging regional anesthetic procedure.

Two Scientific Exhibits concerned fires in the OR. A very engaging and emphatic exhibit was presented by a team from the University of Oklahoma. It was based on a real incident in an outpatient OR where construction in an adjacent space led to an electrical fire that sent copious thick smoke into an OR suite containing pre-op, anesthetized, and post-op patients; electric power, including some of the emergency back-up, failed. Hurried evacuation was conducted, without injuries, but possibly less efficiently than desired. After the debriefing, an educational video (“wrong-way, right-way”) was developed to teach both effective OR evacuation protocols and fire prevention in general (on YouTube as “Fire Safety, OUmedicine”). Another exhibit, from Robert Wood Johnson University Hospital, concerned patients set on fire during MAC procedures on the upper body when there is open delivery (nasal cannulae or mask) of supplemental O2 under a drape over the face (a recent topic of articles and editorials in the national anesthesiology literature). Inappropriate electrocautery use in the O2-enriched surgical field atmosphere ignites a sponge, towel, or drape (or even residual alcohol-based skin prep solution), thus burning the patient, often severely. The presenters showed a modification of a previously presented face mask for the patient that is fashioned from a clear plastic face shield often worn by surgeons in the OR. The unit functions to prevent the supplemental O2 from pooling under the drapes and leaking into the surgical field.

An exhibit essentially dealing with human factors but with great safety implications was presented by a team from the University of North Carolina. A retrospective case analysis revealed that established guidelines for treatment (of PONV in the study example) were often not followed in real-life practice. The conclusion was that there is “significant deviation from existing guidelines,” and the more generalized patient safety implications when the findings are extrapolated are obvious.

Finally, a high-tech approach to the risk of damage from excessive pressure to skin or nerves was presented by a team from Boston University. The wireless disposable thin-film sensors that are applied to a patient’s vulnerable anatomic points measure pressure on the skin and are monitored remotely by telemetry, with alarm thresholds appropriate to the situation. Whether in the OR, ICU, or chronic care, excessive force over time on so-called “pressure points” can cause injury. In the OR, the goal of the technology is to help prevent positioning injuries.

Commercial/Technical Exhibits Include Multiple Safety Themes

In the Commercial Exhibits, many familiar safety themes were presented as they have been in recent years, but there were several new ideas and new twists that attracted attention. Also, it appeared that the trend to more and more international exhibitors with products for sale in the U.S. continued even further this year.

The recurrent themes included information management technology systems that facilitate statistics and data mining designed to help promote quality and safety of care. Some systems touted cloud data storage as an advantage, but without presentation of specific details of any special security features related to potential HIPAA privacy concerns. Exhibits of simulators using high-fidelity patient mannequins as clinical teaching tools revealed several ever-more-realistic interactive features that help bring the simulation experience closer and closer to capturing almost frighteningly realistic presentations. Likewise, a “medical skills trainer” system of “virtual patients” that are synthetic models based on actual anatomy from the Visible Human Project is likely most suited to training for surgical endoscopy, but may well have potential applications for training in various anesthesia procedures. Ultrasound as a tool for regional anesthesia block placement (as well as other potential uses) was widely displayed throughout the vast exhibit hall, although somewhat less so that last year. Likewise, various systems for intraoperative medication safety with bar-code readers and label printers were shown, but not as many as in prior years.

Noninvasive cardiac output measurement devices were more prominently featured than in prior years. One model involves the placement of 4 special sensor electrodes (2 on the chest and one on each carotid artery) that sense the change in red blood cell orientation caused by contraction of the left ventricle—from which a computer can derive stroke volume and then cardiac output by extrapolation, with both displayed continuously. A new device for continuous noninvasive blood pressure monitoring that produces a real-time waveform appearing like that of an intra-arterial catheter pressure tracing involves 2 mini-cuffs on 2 adjacent fingers. A cuff stays inflated enough to plethysmographically sense arterial pressure, and the function shifts to the other finger every 30-60 minutes in order to prevent any potential deleterious effect to a finger distal to a cuff. The manufacturer, from Austria, suggested that, eventually, this device also will calculate and display continuous cardiac output and systemic vascular resistance in real time.

“Thermal management system” is the modern term for a patient warming device. The usual competing claims for different traditional whole-body types were prominent. In addition, one company displayed “dry” IV infusion fluid warmers that have a plastic foam sheath containing a heating element that encircles the normal IV tubing all the way to the IV catheter in the patient, avoiding the need for any additional disposable supplies to facilitate fluid warming and preventing any cooling of the IV infusion in the last tubing segment.

The activated charcoal filter device intended to remove residual potent volatile anesthetic from an anesthesia machine and circuit during or prior to any concern about triggering agents for malignant hyperthermia has had its color changed to bright orange from gray. This is intended to help remind users to remove it after the case for which it was used.

Many Monitoring Modalities

New variants in patient monitoring technologies with safety implications were seen in multiple exhibits. Several of the cerebral oxygen monitors emphasized their potential value during general anesthetics in the beach-chair position, such as for shoulder arthroscopy. The orthostatic pressure-head consideration and also the surgeon’s common request for deliberate hypotension to limit vision-obscuring bleeding in the joint space have been associated with cerebral hypoperfusion injuries in such patients. An entirely different type of new monitor gives a continuous real-time reading of the gas pressure in the endotracheal tube cuff during general anesthesia, purported to help prevent tracheal mucosal injury/pressure necrosis. Another new monitor for patients having surgery in the prone position is a specialized headrest that contains a digital camera attached to a 4.3 inch LCD monitor that clamps to an IV pole and displays a continuous picture of the patient’s eyes from below, assisting in preventing direct trauma to the eyes and possibly also excessive pressure or edema associated with potential vision loss during very long head-down prone cases with major blood loss. Further, a different company stressed the potential value of having an alternative to putting the pulse oximeter sensor on an extremity – a new sensor that is a low-pressure (painless) spring clamp on to the nasal ala, the lateral wall of the nostril. The manufacturer states that problems of limb peripheral vasoconstriction, access, or movement are thus eliminated, and that response times to changes in hemoglobin saturation are faster than with the traditional fingertip oximeter probes.

Regarding monitoring of patients who are not under general anesthesia, a new product responsive to the guideline that all patients having moderate or deep sedation for procedures should have qualitative monitoring for the presence of expired CO2 as a ventilation monitor, one company offered a facemask with a built-in port for connection to a capnograph sampling line. Considering a similar safety issue for post-op patients receiving IV opioids and at risk for ventilatory compromise, one exhibitor presented a new “respiratory motion monitor” involving a strip of electrodes/sensors placed on the patient’s chest that not only measures respiratory rate, but can be calibrated to also display continuous real-time tidal volume and minute ventilation. Company promotional material cited data showing that the device accurately reflected changes seen with each dose of narcotic in a given patient.

Always the Airway

As always, reflecting the fact that airway manipulation issues remain some of the most vexing “unsolved” patient safety challenges, airway tools figured significantly in the commercial exhibits having patient safety implications. Various pieces of airway equipment involving video in a wide variety of permutations and combinations were prominently featured. One, a new “VLM” (video laryngeal mask) device from Spain, seemed to attract extra attention from attendees. It is an intubating supraglottic mask that is also on a reusable curved handle that has a video camera in it and small screen on it, allowing gas delivery and ventilation during video imaging of the larynx through the mask showing the ET being guided into the trachea. There are also integral tubes for suction of airway secretions and also gastric aspiration. The manufacturer also recommends it for “staged extubation,” particularly in morbidly obese patients, where the video mask would be inserted and then the ET withdrawn from the larynx into the pharynx under video imaging, allowing inspection of the airway and also additional time with some airway support from the supraglottic mask as the patient emerges. Another manufacturer, from England, offered a standard-looking laryngoscope handle claimed to contain a rechargeable battery that can last up to one year. One company displayed a video laryngo/broncho scope with a video chip in the tip—rather than in the handle at the proximal end of a fiberoptic bundle—thus giving a bigger picture with a wider field of view in the airway. Further, one other exhibitor showed a flexible light-wand with an attached video camera that transmits its image wirelessly to a 7-inch video screen clamped to the IV pole or equivalent. The wand is completely covered with a disposable impermeable plastic sheath so it does not need cleaning between uses. Directing the wand into the larynx under direct video image allows the previously loaded ET to be advanced off the wand easily into the trachea. Finally, a new ET introducer (that can be used in conjunction with a standard video laryngoscope or without) has a telescoping plastic stylet inside a bendable cannula. The cannula is directed “around the corner” into the airway and the internal stylet is then advanced with the operator’s thumb out of the cannula into the trachea, after which the ET is advanced down over the apparatus, completing the intubation.

Focus on the Future

 

Figure 1. Google Glasses.
http://www.google.com/glass/start/what-it-does/

Possibly the most futuristic exhibit at the meeting was an interactive monitoring system for the OR based on Google Glasses. Still a prototype and not commercially available, the glasses mesh with an information management system that captures all the clinical vital signs and information, which are then projected inside the glasses on to what looks like a miniature monitor screen, constantly within the operator’s field of vision. The glasses will have a microphone allowing recording of spoken notes and also a camera to allow recording video of what the operator is seeing. Eventually, the glasses will become a command center for an automated anesthesia system, where, for example, the concentration of delivered volatile anesthetic could be increased or decreased by simply speaking a command that will be “heard” by the glasses and transmitted wirelessly to the anesthesia machine. The presentation focused on the technology of the glasses, but it is easy to imagine this anesthesia system also incorporating “smart” technology.
As a “smart” follow-on, last but far from least is the apparent arrival of the long-anticipated era of commercially available user-friendly algorithm-driven “decision support” software for anesthesia practice. Cleveland Clinic has partnered with 3 commercial firms to market an anesthesia information management system (AIMS) that incorporates software that automatically provides "advanced clinical guidance" through its "decision support system" to anesthesia professionals using the product. Inspired originally by the example of the autopilot and its component alarms in an airplane, this AIMS processes all the input of vital signs and events with the goal of analyzing the progress of the anesthetic and providing the earliest possible warning of any untoward trends by issuing a “tap on the shoulder” in the form of an advisory alarm and also specific recommended remedies that go beyond “generic tips" or simply a checklist. The overall AIMS also promotes remote simultaneous monitoring of many care locations, implied to enhance supervision, efficiency, and patient safety. The ultimate goal is to extend the technology “throughout the acute care environment,” according to the company.

Overall, patient safety themes among both types of exhibits well reflected the focus of the 2013 ASA Annual Meeting. This emphasizes ongoing efforts that both have yielded success in improving anesthesia patient safety and also demonstrate challenges yet remaining.


 

Dr. Eichhorn, Professor of Anesthesiology at the University of Kentucky, founded the APSF Newsletter in 1985 and was its Editor until 2002. He remains on the Editorial Board and serves as a senior consultant to the APSF Executive Committee.