Afterwords: The Quality of Medical Accident Investigations and Analyses

Adverse events, or accidents, in healthcare can have significant clinical outcomes including loss of property, health (morbidity), and life (mortality). Healthcare accidents have features that make post-event investigations particularly difficult. The investigation and analysis of medical accidents is intended to discover information that explains the nature and cause of what occurred in the interest of preventing or minimizing future loss. The thorough, objective investigation of medical adverse events rarely happens due to the complexity of the environment, litigation, risk, and socio-political implications. Special concerns can undermine investigation depth, breadth, and quality. Healthcare's distinct difference from other high hazard sectors such as aviation and nuclear power requires a unique approach. Healthcare accident examination requires detailed domain knowledge and the use of diverse investigation methods. This paper describes the current state of medical accident analysis, obstacles to understanding such accidents and strategies to overcome them, as well as future investigation and analysis approaches.

Use of colour-coded labels for intravenous high-risk medications and lines to improve patient safety

PROBLEM

Labelling of high-risk drug infusions and lines is a well-recognised safety strategy to prevent medication errors. Although hospital wards characterised by multiple high-risk drug infusions use different types of labelling, little is known about the contribution of a colour-coded label (CCL) to patient safety.

SETTING

A quality improvement programme audit at a tertiary care facility, the Hadassah University Medical Center Ein Kerem, Jerusalem, Israel.

STRATEGY FOR CHANGE

A CCL for intravenous (IV) high-risk medications and lines was designed to promote safer medication administration at the intensive care unit bedside and in other acute wards.

METHODS

The purpose of the study was to compare a new CCL method (intervention) with the current labelling method (control). Laboratory simulation, imitating an intensive care unit, was designed. Safety of the medication treatment and overall duration of nurses' orientation with drugs and lines at the patient's bedside were measured.

EFFECTS OF CHANGE

The use of the new CCL improved proper identification of IV bags (p<0.0001), reduced the time required for description of overall drugs and lines (p = 0.04), improved identification of errors at the treatment setting-drugs and lines (p = 0.03) and reduced the average performance time for overall tasks (p<0.0001).

LESSONS LEARNT

The use of CCLs for IV high-risk medications and lines can improve patient safety and improve medical staff efficiency.

Between scylla and charybdis: a bleomycin-exposed patient with Cohen syndrome

Chemotherapy with bleomycin may cause a syndrome of pulmonary sensitivity to supranormal inspired oxygen concentrations that persists for an unknown period of time after exposure. We present a mentally retarded adolescent patient in whom supranormal inspired oxygen was temporarily necessary to manage her difficult airway. Subsequently her pulmonary function deteriorated acutely and, after intermittent stabilization, irreversibly. In this case, bleomycin exposure may have played a pivotal role in modulating minor insults to trigger fatal acute respiratory distress syndrome (ARDS).

A look into the nature and causes of human errors in the intensive care unit. 1995



Objectives: The purpose of this study was to investigate the nature and causes of human errors in the intensive care unit (ICU), adopting approaches proposed by human factors engineering. The basic assumption was that errors occur and follow a pattern that can be uncovered.

Design: Concurrent incident study.

Setting: Medical-surgical ICU of a university hospital.

Measurements and main results: Two types of data were collected: errors reported by physicians and nurses immediately after an error discovery; and activity profiles based on 24-h records taken by observers with human engineering experience on a sample of patients. During the 4 months of data collection, a total of 554 human errors were reported by the medical staff. Errors were rated for severity and classified according to the body system and type of medical activity involved. There was an average of 178 activities per patient per day and an estimated number of 1.7 errors per patient per day. For the ICU as a whole, a severe or potentially detrimental error occurred on average twice a day. Physicians and nurses were about equal contributors to the number of errors, although nurses had many more activities per day.

Conclusions: A significant number of dangerous human errors occur in the ICU. Many of these errors could be attributed to problems of communication between the physicians and nurses. Applying human factor engineering concepts to the study of the weak points of a specific ICU may help to reduce the number of errors. Errors should not be considered as an incurable disease, but rather as preventable phenomena.

Detection of firearm imprints on the hands of suspects: effectiveness of PDT reaction

Pyridyldiphenyl triazine (PDT) and three of its analogues were compared as practical reagents for visualizing unseen impressions left on the hands of a person who has held a firearm. The parent compound, PDT, gave the best results using intensity and clarity as measuring criteria. The effectiveness of the PDT reaction was then studied on 147 volunteers who had held firearms in their hands. Identifiable impressions of the metallic parts of the weapons were developed on the hands of 103 volunteers (70%). Results with females were slightly higher than with males, however, the difference was possibly statistically insignificant, and needs further study. Ferroprint and Ferrotrace, 5 commercial preparations that are based on the PDT reaction, have become a part of the professional equipment of every crime scene technician in Israel.

Perceptual-motor coordination in an endoscopic surgery simulation

BACKGROUND

This study examined perceptual-motor coordination with an apparatus that simulated a situation representative of endoscopic surgery.

METHODS

Participants were trained with one arrangement of the apparatus, then tested with an alternative arrangement in which either the positions of the camera, the surgeon, or the objects in the surgical field were altered.

RESULTS

Results showed that changes of either the camera's position or the surgeon's position disrupted performance. However, when the camera and surgeon positions were changed together, skilled performance was maintained.

CONCLUSIONS

This suggests that skill depends on a consistent mapping between the virtual hands and eyes, but not on the particular visual or motor orientations. The results suggest that movements of the camera during surgery can disrupt coordinated action. Also, in the design of training simulators, the mapping between camera and instruments may be more important than the static appearance of the displays or the topology of the movements.

Successful resuscitation using aminophylline in refractory cardiac arrest with asystole

Adenosine antagonists may have therapeutic potential in cardiopulmonary resuscitation. Aminophylline, a widely available adenosine antagonist, is not included in the Guidelines for Advanced Life Support by the European Resuscitation Council or the American Heart Association. This report addresses a case of out-of-hospital cardiac arrest caused by inferior wall myocardial infarction in which effective circulation was restored subsequent to aminophylline administration, after prolonged conventional resuscitation had resulted in asystole.

The safety of air transportation of patients with advanced lung disease. Experience with 21 patients requiring lung transplantation or pulmonary thromboendarterectomy

Air travel can cause severe respiratory decompensation in a patient with advanced lung disease due to high altitude hypoxemia. We report our experience in flying 21 patients with advanced lung disease to a medical center remote from Israel for lung transplantation or pulmonary thromboendarterectomy (PTE). All patients had severe lung disease with marked hypoxemia (PaO2, 40 to 59) and 16 had significant pulmonary hypertension. Nine patients (with emphysema and pulmonary fibrosis) required single lung transplant, four (with cystic fibrosis and emphysema) required double-lung transplant, six (with primary or secondary pulmonary hypertension) required heart-lung transplant, and two (with major vessel pulmonary thrombosis) required PTE. All patients were flown by commercial aircraft to centers located 2,634 to 13,181 km away from Israel. Length of flight was between 4 and 21 h. Patients were given oxygen supplementation during the flight and were monitored by portable oximeters. All but three patients were hemodynamically stable and 19 of them were escorted by physicians. All but one hemodynamically unstable patient who died on board arrived safely at their destinations. We conclude that with careful preparation, sufficient oxygen supply, oximetric monitoring, and medical escort, almost any patient with severe lung disease can travel by air to any necessary destination.

Assessment of physician competence in prehospital trauma care

In an attempt to develop a model to measure the competence of physicians providing emergency care under difficult field conditions, 75 Israeli army medical corps physicians were evaluated through the use of four instruments: a debriefing interview, peer assessment, self-assessment and written examination. The special on-site assessment model was designed to examine actual events, enabling an assessment of performance in real situations rather than simulated cases. Significant positive correlations were found between the results of the written examination and the peer evaluation on two of four measures (r = 0.36, P = 0.001; r = 0.23, P = 0.05) as well as on the two measures regarding self-evaluation and peer evaluation (r = 0.54, P = 0.001; r = 0.38, P = 0.05). It was found that those physicians who were trained in the army's medical officer course scored significantly higher on the written examination (P = 0.001) and were rated more highly by their senior peers (P = 0.048) than those who did not receive such training. It was concluded that it is advantageous to use a combination of knowledge (written examination) and performance (peer assessment or self-assessment) measures in order to arrive at a more comprehensive assessment of competence. In addition, the written examination format should be expanded and developed to include more clinical vignettes requiring treatment decisions, making this instrument a more clinically oriented measure of physician competence in trauma care.

A look into the nature and causes of human errors in the intensive care unit

OBJECTIVES

The purpose of this study was to investigate the nature and causes of human errors in the intensive care unit (ICU), adopting approaches proposed by human factors engineering. The basic assumption was that errors occur and follow a pattern that can be uncovered.

DESIGN

Concurrent incident study.

SETTING

Medical-surgical ICU of a university hospital.

MEASUREMENTS AND MAIN RESULTS

Two types of data were collected: errors reported by physicians and nurses immediately after an error discovery; and activity profiles based on 24-hr records taken by observers with human engineering experience on a sample of patients. During the 4 months of data collection, a total of 554 human errors were reported by the medical staff. Errors were rated for severity and classified according to the body system and type of medical activity involved. There was an average of 178 activities per patient per day and an estimated number of 1.7 errors per patient per day. For the ICU as a whole, a severe or potentially detrimental error occurred on the average twice a day. Physicians and nurses were about equal contributors to the number of errors, although nurses had many more activities per day.

CONCLUSIONS

A significant number of dangerous human errors occur in the ICU. Many of these errors could be attributed to problems of communication between the physicians and nurses. Applying human factor engineering concepts to the study of the weak points of a specific ICU may help to reduce the number of errors. Errors should not be considered as an incurable disease, but rather as preventable phenomena.

Utility of postmortem computed tomography in trauma victims

A possible way to circumvent the continuing decline in the number of autopsies is to perform computed tomography after death. The present study compares the pathologic findings of postmortem CT tomography (PMCT) in trauma fatalities with those disclosed upon conventional forensic autopsy. Within 6 hours of death, the bodies of 25 trauma victims underwent total body CT scanning, all with permission of the relatives, followed by conventional autopsy in 13 cases under court order. The pathologist and roentgenologist were unaware of each other's findings. The pathologic findings of PMCT plus conventional autopsy provided more information than either examination alone. Of the total 127 pathologic findings, 44.9% were diagnosed by both conventional autopsy and PMCT, 29.9% were not revealed by PMCT, whereas conventional autopsy missed 25.2%, and PMCT detected more bone injuries than did autopsy, whereas the latter was superior to PMCT in discovering soft-tissue pathologic states. In all, PMCT revealed 70.5% and autopsy 74.8% of the pathologic states. Although PMCT was not more effective than conventional autopsy in exposing pathologic entities, it increased the yield of findings when combined with conventional autopsy. Where conventional autopsy is unattainable, PMCT may be effective in shedding light on the pathologic state and mechanism of death in trauma fatalities.

Pregraduate training in emergency medicine

A panel session on undergraduate education in Emergency Medicine from a worldwide perspective was conducted at the Seventh World Congress of Emergency and Disaster Medicine in Montreal, in May, 1991. Desmond Colohan MD, of the University of Toronto (Canada) was the panel moderator. Panel speakers were: Louis Binder MD, Texas Tech University Health Services Center (USA); Wolfgang Dick MD, University of Mainz (Germany); Bernard Nemitz MD, Faculty de Medicine d'Ameins (France); Yoel Donchin MD, Hadassa Medical Organization (Israel); and Noriyoshi Ohashi MD, Tsukuba Medical Center (Japan).

Cardiac vagal tone predicts outcome in neurosurgical patients

OBJECTIVE

To evaluate the relationship between presurgical levels of cardiac vagal tone and outcome in neurosurgical patients.

DESIGN

Prospective series.

SETTING

Respiratory ICU in a university hospital.

PATIENTS

Fifty-one adults admitted to the respiratory ICU between 1982 and 1985. Forty-two patients were scheduled for elective neurosurgery, and nine patients suffered from head trauma.

INTERVENTIONS

Ten minutes of electrocardiographic (EKG) data were recorded before medical intervention. Neurosurgical patients scheduled for surgery had EKG data recorded 24 hrs before their operation. Trauma patients had EKG data recorded immediately after arrival in the respiratory ICU.

MEASUREMENTS AND MAIN RESULTS

Cardiac vagal tone was evaluated using a vagal tone index, quantified from the EKG. Cardiac vagal tone monitored before surgical intervention significantly distinguished between the outcome groups only for the elective neurosurgical patients. Age, gender, heart rate, Glasgow Coma Scale scores, and tumor location, size, and malignancy were not related to outcome in the elective neurosurgery group. However, within the trauma group, low Glasgow Coma Scale scores were significantly related to poor outcome.

CONCLUSIONS

Cardiac vagal tone may offer important predictive value by alerting the physician to the functional consequence of head injury. Information relating to autonomic nervous system functioning, such as the vagal tone index used in this study, may provide additional information that will complement the computed tomography scan results. This study demonstrates that the vagal tone index is a predictive factor that may be efficiently extracted from the heart rate pattern routinely monitored in ICUs.

[Assessment of IDF physicians in in-field trauma]

The system of care delivery of in-field trauma was assessed, leading to suggestions for improving the system and military medical training. This study reports the feasibility and validity of various methods of assessing the performance of Israel Defense Force physicians in administering trauma care. The methods included a standardized medical debriefing with filling in of a report form by a senior traumatologist, his review of the physician's performance, self-assessment by the physician, and a written test. 5 senior traumatologists with extensive experience in military trauma care were trained to assess the physicians' performance within 24-48 hours of incidents involving moderate to severe trauma injuries. 75 physicians who had been involved in the care of the in-field trauma patients during a 1-year period, November 1988 to October 1989, were assessed. Analysis of the results clearly indicated 2 areas for assessment: a) knowledge, mainly levels of comprehension and application in relevant areas of trauma and b) performance, including immediate diagnosis, treatment skills, and triage. The best method for evaluating knowledge was the written test, not peer review nor self-evaluation. However, the traumatologist's evaluation of care performance was highly correlated with the physician's self-assessment. For comprehensive assessment of in-field care it is advisable to integrate the 2 methods: performance review by a traumatologist and a comprehensive written test. Information gained from such assessment could improve the planning of in-service trauma training and the posting of physicians within the military framework.

A novel approach to military combat trauma education

A heterogeneous group of 77 physicians on compulsory or reserve military service were exposed to a 5-day course in trauma management, specifically designed for military medical personnel. Cognitive knowledge of trauma care delivery of the medical officers was assessed by means of multiple-choice written tests, which were held before and upon completion of the course. The significantly improved (p less than 0.0001) scores of the post-course test demonstrate the value of a condensed trauma educational program. Analysis of the background variants (i.e., medical education, military, and residency training, and time since graduation) revealed that the relatively short but intensive course sufficed to surmount the difficulties inherent in instructing a student body composed of individuals with dissimilar professional experience. We advocate the institution of a compact course in trauma treatment, with the specific aim of enhancing the medical officer's knowledge in this critical field of medical care.

Trauma anesthesia for disasters. Anything, anytime, anywhere

Field anesthesia can be practiced safely and effectively but requires special training to acquire familiarity with the techniques. Because field anesthesia may be required even in sophisticated countries for entrapment situations, skill should be maintained by practicing the appropriate techniques on a regular basis. Field anesthetic techniques are not second rate methods; they are just different. Although improvisation in the disaster situation has merit, it is not the place for experimenting with new and untried techniques.

Military medicine: trauma anesthesia and critical care on the battlefield

This article presents a few of the basic guidelines that must be considered once a decision is made to provide anesthesia and advanced surgical care in the battlefield--or in civilian catastrophes (for example, terrorist incidents, and man-made or natural disasters) that resemble the battlefield. However, it must be stressed that the most central consideration in battlefield anesthesia is the selection, training, and experience of the battlefield anesthesiologist. There are strict guidelines for providing safe anesthesia under the dire circumstances of war or similar civilian circumstances; the properly trained and experienced TA/CCS, however, will be best able to deliver battlefield anesthesia and to improvise equipment and agents for its safest delivery in those circumstances.

Pulmonary barotrauma including orbital emphysema following inhalation of toxic gas

Severe pulmonary barotrauma occurred following smoke and toxic gas inhalation in a 20-year-old male. He developed pneumothorax, pneumomediastinum, and extensive facial subcutaneous emphysema which intensified during treatment with positive pressure ventilation. Following the appearance of diplopia and exotropia, orbital emphysema was demonstrated radiologically. The diplopia and exotropia were manifestations of mechanical interference in extra-ocular muscle function by the intra-orbital air, an unusual expression of pulmonary barotrauma.

Respiratory sinus arrhythmia during recovery from isoflurane-nitrous oxide anesthesia

Heart rate and respiratory patterns were monitored in ten ambulatory female patients undergoing elective laparoscopy. The patients were anesthetized with isoflurane-nitrous oxide. An index of cardiac vagal tone determined from the heart rate pattern by quantifying the amplitude of respiratory sinus arrhythmia was elevated over four 10-min periods: before induction of anesthesia; during maintenance of anesthesia; upon arrival in the recovery room; and 20-30 min later when the patient was fully conscious. All ten patients' vagal tones were lowest during maintenance of anesthesia. During the recovery periods vagal tone increased and approached the conscious level. On-line analysis of respiratory sinus arrhythmia may provide a physiological index of the level of anesthesia and the rate of recovery.

Metkephamid-induced Flehmen in lambs

When metkephamid, a systemically active analog of methionine enkephalin, was administered intracisternally to male or female prepubescent lambs as early as the first week of life, we observed a behavioral pattern akin to Flehmen, which is a well-characterized grimace displayed by mature ungulates during mating. This metkephamid-induced Flehmen was preceded by transient bradycardia and apnea followed by somnolence for approximately 1 hour, during which Flehmen was observed intermittently. Pretreatment with the specific opiate antagonist, naloxone, blocked this behavioral response. These observations indicate that endogenous opioid peptides may be involved in Flehmen.

Spectral analysis of fetal heart rate in sheep: the occurrence of respiratory sinus arrhythmia

Respiratory sinus arrhythmia is a pattern of rhythmic variation in the heart rate that occurs at the frequency of respiration and is mediated principally by the vagus nerve. Spectral analysis can decompose the variance of a series of sequential measures into constituent frequencies to measure and verify whether there is respiratory sinus arrhythmia in utero in the fetal lamb. Recordings of heart period were obtained from electrodes implanted under fetal skin in six chronic preparations. Respiratory rate and heart period were recorded immediately after delivery and daily for the next 5 days. Respiratory sinus arrhythmia was clearly demonstrated in the neonatal lambs, and the same frequency of respiratory sinus arrhythmia was observed in the fetus and in the newborn lamb (0.8 to 0.1 Hz). There was a reproducible pattern of change in respiratory sinus arrhythmia from 27 days before delivery until term, with a decline in the amplitude of respiratory sinus arrhythmia 4 to 8 days before delivery. We conclude that respiratory sinus arrhythmia was demonstrated in fetal sheep and may serve as an indicator of the integrity of the central nervous system in the fetus and the neonate.

Epidural morphine does not affect the duration of action of epidural 2-chloroprocaine following Caesarean section

The effect of epidural morphine on the duration of action of epidural 2-chloroprocaine was studied in a double-blind fashion in 30 patients following elective Caesarean section. When compared to epidural saline controls (n = 15), patients (n = 15) who received epidural morphine (4.0-5.0 mg) did not experience a prolongation or reduction in the duration of the somatic or sympathetic nervous system blockades produced by epidural 2-chloroprocaine.

Fetal response to voluntary maternal hyperventilation. A preliminary report

Maternal hyperventilation can cause transient reduction in fetal oxygen tension. Fifty women with normal and high-risk pregnancies, between the 32nd and 43rd week, were voluntarily hyperventilated; in 33, fetal heart rate (FHR) acceleration or transient tachycardia were observed (reactive FHR). Of the 33 pregnancies the outcome was good in 30 (91%) as judged by the absence of perinatal death, no fetal distress in labor and no intrauterine growth retardation (IUGR). In 14 patients in whom there was no FHR response to maternal hyperventilation (non-reactive FHR), the outcome of pregnancy was significantly worse; one infant died neonatally, 10 were either chronically (IUGR), or acutely distressed. Only in 3 was the outcome good (21%). The study showed that there is good correlation between a "reactive" FHR and favorable neonatal outcome, and between a "non-reactive" FHR and an unfavorable neonatal outcome.

Epidural morphine for the control of pain after cesarean section

Epidural morphine was evaluated for the control of postoperative pain after cesarean section (CS). Sixty-five patients undergoing elective CS with epidural bupivacaine were studied. Of these, 40 were given a single dose of 4 mg of morphine through an epidural catheter on termination of surgery. The remaining 25 patients received no postoperative epidural medication. In all cases, the catheters were withdrawn before the patients left the operating theater and 15 mg doses of papaveretum (OMNOPON) ordered as required for pain relief. The ward staff was unaware of the study. The time between the termination of surgery and the first administration of postoperative narcotic was noted, as was the total dose, for 48 h. The epidural morphine was associated with a prolonged period of postoperative analgesia and a greatly reduced total papaveretum requirement for the 48 h (30.9 mg for the study group in contrast to 67.6 mg for the controls). The difference between the two groups was significant (P less than 0.001). We concluded that epidural morphine is an efficient method for the control of postoperative pain following CS, a single dose of 4 mg providing relief from pain for 8 to 12 h and sometimes longer.

Traumatic rupture of the thoracic aorta during pregnancy. Surgical considerations

This is a report of successful management of a traumatic rupture of the thoracic aorta in pregnancy. Both mother and daughter are alive and well 24 months after the injury. The various aspects of the surgical and supportive treatment are discussed.

Prolonged effect of bupivacaine hydrochloride after cuff release in i.v. regional anaesthesia

Bupivacaine hydrochloride 0.25% and 0.50% solutions, were administered 115 times by the i.v. regional route to 64 surgical patients and in 38 subjects suffering from pain syndromes. The clinical effects were limb numbness up to 20 h following cuff release, while analgesia and weakness of the limb muscles were evident 5 h after the tourniquet. Clinical and electrophysiological findings revealed a dose relationship of the effects. Toxic signs were noted in three patients in whom the cuff was released in a one-step fashion. In 11 patients, mean arterial plasma concentrations of bupivacaine reached 3.7 micrograms ml-1 after administration of 0.5% bupivacaine 40 ml, 5 min after final cuff release, and decreased gradually thereafter. In selected conditions which do not require a bloodless field and in certain intractable pain states, i.v. regional anaesthesia with high-dose bupivacaine (200 mg of 0.5% solution) may be a simple and effective technique.

Epidural morphine analgesia in second-trimester induced abortion

Epidural administration of 2 mg of morphine to 16 patients who were undergoing induced abortion in the second trimester of pregnancy abolished labor pains in 10 of them within 10 to 20 minutes after treatment was begun. The pain did not recur until the abortion process started, sometimes hours later. In one patient, the relief of pain was achieved with an additional top up dose of 1 mg 15 minutes later. In the other five patients in whom the morphine had no appreciable effect, the addition of 4 ml of 0.5% bupivacaine hydrochloride, also injected epidurally, successfuly abolished pain. Because of the beneficial and prolonged action of morphine, as well as the lack of side effects, continuous epidural analgesia with low doses of it--supplemented, if necessary, with small quantities of bupivacaine--is effective for treatment of labor pains in induced abortion in the second trimester of pregnancy. The involvement of the anesthetist from the very beginning of the induction procedure is highly recommended.

Effect of sodium bicarbonate on the kinetics of bupivacaine in i.v. regional anaesthesia in dogs

Changes in pH studied in vitro affected considerably the distribution of bupivacaine between the erythrocyte and incubation medium: in an acidic medium, the uptake of bupivacaine by erythrocytes was decreased. The acidosis induced in vivo in dogs' limbs during i.v. regional anaesthesia (IVRA) with bupivacaine was corrected by injecting sodium bicarbonate into the occluded limb. The concentration of bupivacaine in the cephalic vein was measured in dogs under. IVRA. After removal of the tourniquet, the drug concentration-time relationship showed a biexponential pattern of decline. Injection of sodium bicarbonate into the limb 10 min before the release of the tourniquet suppressed the rate at which the concentration of bupivacaine decreased during the second phase. This slower rate of drug release from the tissues may prolong residual analgesia.

Emotional reactions during lumbar extradural anaesthesia

The degree of anxiety of 26 male and female patients undergoing hernia repair while receiving lumbar extradural anaesthesia was measured using the galvanic skin response. The single, most anxiety-provoking feature during the surgical procedures proved to be verbal interactions directly concerned with the patient's well-being. The psychological implications of this feature are discussed.