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Fire in the OR! How would you have responded? What was done well? What could have been improved upon?
This is a video of a simulation done a number of years ago at the Winter Institute For Simulation Education and Research (WISER) at the University of Pittsburg. It is used with permission of Laederal Corporation and the WISER simulation center.
Video courtesy of WA Kofke M.D.
Precise definitions of disease may change as new diagnostic modalities, newer clinical research and better clinical experience become available. The result of the recent ESC/ACCF/AHA/WHF expert consensus conference to develop a Universal Definition of Myocardial infarction is now available (http://content.onlinejacc.org/cgi/content/full/j.jacc.2007.09.011v1 ). This effort incorporates troponin changes into the definition and clarifies what to call the clinical syndrome of small troponin elevations after PCI or other coronary artery manipulations. If you do not know the difference between myocardial infarction and myocardial necrosis this article is worth reviewing.
David S. Smith, M.D., Ph.D.
Dr. Hecker calls our attention to two studies from Duke University concerning dysfunctional banked blood. Bennett-Guerrero and associates analyzed changes that occur during RBC storage. They showed that, when stored according to American Association of Blood Banks standards, red blood cells rapidly lost nitric oxide (S-nitrosohemoglobin levels fell). RBC deformability also decreased as did the ability of the banked blood to produce RBC dependant vasodilation. This loss of nitric oxide may compromise RBC mediated hypoxic vasodilation and stored RBC may be deficient with respect to their ability to deliver oxygen to tissues (Evolution of adverse changes in stored RBCs, PNAS 2007;104:17063- 68). In another paper, Reynolds and colleagues demonstrated that renitrosylation of the banked blood during storage increased the S-nitrosohemoglobin content and restored vasodilatory activity. They also demonstrated that infusions of renitrosylated RBCs produced greater blood flow in canine coronary arteries than did infusion of the denitrosylated RBCs (S-nitrosohemoglobin deficiency: A mechanism for loss of physiological activity in banked blood. PNAS 2007;104:17058-62). According to Reynolds et al, recent studies have demonstrated that RBCs mediate a nitric oxide based hypoxic vasodilatory activity. Nitric oxide attached to hemoglobin is released under hypoxic conditions. Thus in addition to carrying oxygen, hemoglobin is an important factor in regulating local blood flow. This work and the work of others provides a mechanistic explanation for matching blood flow with metabolic demand in peripheral tissues and also for the matching of ventilation to perfusion within the lung. The hypothesis that banked blood may improve oxygen carrying capacity but may not improve tissue oxygen delivery as long as it is nitric oxide deficient is interesting and consistent with our evolving understanding of the role of nitric oxide in the control of tissue blood flow.
James Hecker M.D., PhD. is Assistant Professor of Anesthesiology and Critical Care at the Hospital of the University of Pennsylvania
Dr. Kukafka discusses the NYHA heart failure classification system The New York Heart Association (NYHA) developed its initial heart failure classification system in 1928. Historically, the NYHA heart failure classification used a patient’s functional capacity to categorize patients. Patients were placed in one of four groups. Class I patients had no symptoms with ordinary physical activity and Class IV patients had symptoms with minimal activity or even at rest. Symptoms included angina, dyspnea, palpitations, and fatigue.
The NYHA heart failure classification system has been used to 1) gauge patients’ overall heart failure symptom burden, 2) follow patients’ status over time, 3) to monitor effects of therapeutic interventions, 4) to compare patients to one another, and 5) as a tool for perioperative risk assessment. For example, a NYHA functional class IV is listed among “active cardiac conditions for which the patient should undergo evaluation and treatment before noncardiac surgery” in the ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery, Class 1 LOE B. However this classification system may be inherently imprecise and is prone to significant interobserver variability.
In 1994, the NYHA heart failure classification system was further revised, which included a second category in addition to the patient’s functional capacity: objective assessment. Using data from electrocardiograms, stress tests, echocardiograms, and radiological imaging, patients were categorized into groups A through D, where group A patients had no objective evidence of cardiovascular disease and group D patients had objective evidence of severe cardiovascular disease.
Functional Capacity |
Objective Assessment |
Class I. Patients with cardiac disease but without resulting limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea, or anginal pain. |
A. No objective evidence of cardiovascular disease. |
Class II. Patients with cardiac disease resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea, or anginal pain. |
B. Objective evidence of minimal cardiovascular disease. |
Class III. Patients with cardiac disease resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes fatigue, palpitations, dyspnea, or anginal pain. |
C. Objective evidence of moderately severe cardiovascular disease. |
Class IV. Patients with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms of heart failure or the anginal syndrome may be present even at rest. If any physical activity is undertaken, discomfort is increased. |
D. Objective evidence of severe cardiovascular disease |
Examples of patient classification:
REFERENCES:
1) The Criteria Committee of the New York Heart Association. Nomenclature and Criteria for Diagnosis of Diseases of the Heart and Great Vessels. 9th ed. Boston, Mass: Little, Brown & Co; 1994:253-256.
2) Fleisher LA, et al: ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery). Circulation. 2007;116.
3) Hunt SA, et al: ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure): developed in collaboration with the American College of Chest Physicians and the International Society for Heart and Lung Transplantation: endorsed by the Heart Rhythm Society. JACC, 2005;46;1-82.
Dr. Kukafka is a cardiac anesthesia fellow at UPENN
James Szalados MD, JD (Anesthesiology News, August 2007) discusses “the legal implications of anesthesia record shortcomings.” He cites two recent cases in which failure to properly review anesthesia records contributed to problems in defense. In case one there was a 93 minute gap in vital sign recording which was attributed to interrupted data transmission to the automated anesthesia record. In a second case a precipitous fall in end tidal carbon dioxide was not documented on the paper print out but was present when the stored data base was accessed. Dr. Szalados raises the following questions: 1) “which of the records – paper or electronic – is the “official” medical record for the case?” 2) “What is the duty of the professional to verify his or her records?” Dr. Szalados notes that there is the expectation that “medical records are … accurate, legible and complete; the signing physician is expected to authenticate the record and vouch for its truthfulness; and the use of an automated record does not necessarily absolve the signing physician of liability.” Dr Szalados notes that the “determination of which document represents the “official” medical record is … a fairly settled area of law... wherever the automated data are first collected and stored is the “original” record. Copies are never considered to have the same value as the actual document and may be contested. Printouts are secondary documents that may not accurately reflect the electronic data…When printouts and “final” versions of electronic patient records do not concur, the defense case will be unexpectedly compromised at trial.” A key difference between a manually generated anesthesia record and an electronic record is that the paper record of a manually generated record is the “original” record. In contrast an electronic record may contain information in its data base not present on the paper print out that could prove significant if care becomes a point of litigation.
David S Smith M.D., Ph.D.
An Associated Press article from April 10, 2007 discusses the plight of a patient who became severely depressed and committed suicide by a self inflicted gun shot wound after being aware during surgery. According to the lawsuit filed, the anesthesiologists gave the patient muscle relaxants but failed to administer any general anesthetic until 16 minutes after the first abdominal incision. The lawsuit claims that the 71 year old man was never told of the improper anesthesia administration and was tormented by doubts as to whether his memories were real. The lawsuit claims that for two weeks after his surgery the victim could not sleep, could not be left alone, suffered nightmares, and thought that people were trying to bury him alive (www.boston.com).
David S. Smith, M.D., Ph.D.
Drs. Kofke and Scott faced a challenge, an intubated intensive care patient required an MRI. The MRI compatible ventilator was broken. Instead of cancelling the case, Dr Kofke set up a Mapelson F circuit that allowed the patient to be manually ventilated from the foot of the MRI table. The jury-rigged system worked well and justified once again the need for knowing about Mapelson circuit design.
An excellent review of Mapelson circuit design can be found at Anesthesia Breathing Systems by Professor MR Shankar and BS Shanker M.D.
Dr. WA Kofke is Professor of Anesthesiology and Critical Care and Director of Neurosurgical Anesthesia at UPENN
Benjamin Scott M.D. is an anesthesia resident at UPENN
Handoffs are ubiquitous, relief for lunch, relief at the end of a shift, transfer of the patient to nursing in the PACU or SICU all involve a handoff. Analysis of sentinel events by the Joint Commission has shown that Inadequate or inappropriate communication is a major source of medical error. Some have estimated that communication may be involved in up to 26% of medical error. Handoffs are not unique to medicine. However in other endeavors in which handoffs are common such as air traffic control the handoffs are structured and practiced to increase the probability of a successful transition. In medicine handoffs are often unstructured, ad hoc and often done hurriedly as one care giver is on the way home or going to another assignment (Solet DJ et al: Lost in translation: Challenges and opportunities in physician-to-physician communication during patient handoffs. Acad Med 2005;80:1094-1099). Pothier et al observed the handoff process for 12 simulated patients over 5 consecutive handoff cycles. A purely verbal handoff led to loss of all data after three cycles. Note taking resulted in 69% of the data not being correctly transmitted. When a printed form was combined with a verbal handoff the data loss was minimal (Pilot study to show the loss of important data in nursing handover. Br J Nurs 2005;14:1090-3). Other studies have found that a structured handoff tends to minimize the loss of information. To help address the problem of handoffs the Joint Commission has adopted patient safety goal 2E as a requirement for health care institutions seeking their accreditation. Specifically health care institutions such as HUP must Implement a standardized approach to “hand off” communications, including an opportunity to ask and respond to questions.
At a national level AORN (Association of Perioperative Registered Nurses) is taking a leadership role in adapting standardized approaches to handoffs to the perioperative environment (http://www.aorn.org/PracticeResources/ToolKits/PatientHandOffToolKit/ ). There are a number of structured approaches to medical handoffs. Though AORN has not advocated a particular approach all of the advocated approaches have common elements including 1) handoff done in a setting of minimal interruption, 2) handoff done in a way that allows for questions and read back, and 3) handoff done in a consistent and predictable manner to minimize the risk of lost or overlooked information (see for power point presentation on this subject http://www.aorn.org/docs_assets/55B250E0-9779-5C0D-1DDC8177C9B4C8EB/44F75AF4-17A4-49A8-867C0BA6257E239D/HandOff_Standardizing.ppt#256,1,Standardizing Hand offs for Patient Safety ). Many feel that the I-SBAR approach is consistent and easily modifiable to the perioperative environment and to various levels of patient complexity. In this paradigm I stands for introduction, S for Situation (current issues), B for Background, A for Assessment and R for Recommendations/Requests. Within each category there are subcategories that help structure the communication and decrease the risk that key pieces of information are. Another pneumonic is “I Pass the Baton” standing for Introduction, patient, assessment, situation, safety concerns, background, actions, timing, ownership and next. A final popular pneumonic is 5-Ps which stands for patient, plan, purpose, problems, precautions.
The key question relates to whether or not transfers of patient care between residents or between residents and non anesthesia care givers would be improved by a more formal approach compared to what is currently being done?
David S. Smith, M.D., Ph.D.
*Wrong sided surgery continues as a problem in the State of Pennsylvania. According to the Patient Safety Authority* (June, 2007 press release) the data show “every other day in Pennsylvania healthcare facilities an actual adverse event or near miss of wrong-site surgery occurs... In a 30-month time period (June 2004-December 2006) the Authority received reports of 427 near misses and serious events of wrong site surgery...Of the events that reached the patient in the operating room, 69% were wrong sided surgeries, 14% were wrong body part surgeries, 9% were wrong procedure and 8% were wrong patient…Orthopedic and ophthalmologic procedures were the most common for wrong-site surgeries.” The risk factors for wrong site surgeries included: “multiple procedures and or multiple surgeons, communication breakdowns, time pressures, incomplete preoperative assessments, and organizational cultural factors that are not conducive to promoting teamwork such as an attitude that surgeon’s decisions should never be questioned.” In many cases the patient or the family was the key factor in preventing the wrong site surgery from occurring (see Patient Safety Advisory Newsletter June 2007 for a very detailed discussion of this problem http://www.psa.state.pa.us/psa/lib/psa/advisories/v4n2_june_2007/jun_2007_v4_n2_article_wrong-site_surgery.pdf ).
The Patient Safety Authority is an independent state agency charged with taking steps to reduce and eliminate medical errors by identifying problems and recommending solutions that promote patient safety. Their web site is very good and their newsletters very helpful.
David S. Smith, M.D., Ph.D.
In a 1989 letter to the editor of Anesthesiology, Barbara Leighton described her Greengrocer's Model of the Epidural Space. We have found this "simulator" to be a fun and useful introduction to epidural anesthesia. Many of our residents prefer this model to more expensive simulators. The Department's version is as shown:
According to Dr. Leighton the banana represents in turn the skin, subcutaneous tissue and ligamentum flavum. She noted that the average banana can be used about 30 attempts. A balloon (not visible in this photo) represents the Dura. As Dr. Leighton noted in her letter, the thin skin of an air or water filled balloon identifies undue pressure on the "dura" with a loud dry pop (double click on each image to enlarge it)
David S. Smith, M.D., Ph.D.
