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K L Posner

Publications and source records attributed to K L Posner.

At least 19 recordsLinked to original sources
PubMed2002

Unexpected cardiac arrest among children during surgery, a North American registry to elucidate the incidence and causes of anesthesia related cardiac arrest.

Relatively rare adverse events, such as unexpected cardiac arrest, are difficult to study in the clinical setting. These events are often unpredictable in their occurrence (prompting interest in their investigation) and do not occur with sufficient frequency in any single institution to provide an adequate sample for analysis. A disease-specific registry is an epidemiological technique that can be used to collect data on a set of relatively rare unpredictable events. This approach was adopted for investigation of cardiac arrest in children when it became apparent from analysis of malpractice claims that a significant clinical problem existed. This report provides a brief historical account of the development of the Pediatric Peri-Operative Cardiac Arrest (POCA) Registry and elaborates on the methodology including strengths, weaknesses, and practical implementation issues.

Adolescent↗
PubMed1999

Comparative efficacy and safety of ondansetron, droperidol, and metoclopramide for preventing postoperative nausea and vomiting: a meta-analysis.

UNLABELLED: Postoperative nausea and vomiting are important causes of morbidity after anesthesia and surgery. We performed a meta-analysis of published, randomized, controlled trials to determine the relative efficacy and safety of ondansetron, droperidol, and metoclopramide for the prevention of postoperative nausea and vomiting. We performed a literature search of English references using both the MEDLINE database and a manual search. Double-blinded, randomized, controlled trials comparing the efficiency of the prophylactic administration of ondansetron, droperidol, and/or metoclopramide therapy during general anesthesia were included. A total of 58 studies were identified, of which 4 were excluded for methodological concerns. For each comparison of drugs, a pooled odds ratio (OR) with a 95% CI was calculated using a random effects model. Ondansetron (pooled OR 0.43, 95% CI 0.31, 0.61; P < 0.001) and droperidol (pooled OR 0.68, 95% CI 0.54, 0.85; P < 0.001) were more effective than metoclopramide in preventing vomiting. Ondansetron was more effective than droperidol in preventing vomiting in children (pooled OR 0.49; P = 0.004), but they were equally effective in adults (pooled OR 0.87; P = 0.45). The overall risk of adverse effects was not different among drug combinations. We conclude that ondansetron and droperidol are more effective than metoclopramide in reducing postoperative vomiting. IMPLICATIONS: We performed a systematic review of published, randomized, controlled trials to determine the relative efficacy and safety of ondansetron, droperidol, and metoclopramide for preventing postoperative nausea and vomiting. Ondansetron and droperidol were more effective than metoclopramide in reducing postoperative vomiting. The overall risk of adverse effects did not differ.

Adult↗
PubMed1999

Adverse cardiac outcomes after noncardiac surgery in patients with prior percutaneous transluminal coronary angioplasty.

UNLABELLED: In this retrospective cohort study, we compared adverse cardiac outcomes after noncardiac surgery among patients with prior percutaneous transluminal coronary angioplasty (PTCA), patients with nonrevascularized coronary artery disease (CAD), and normal controls. Inpatient hospital discharge abstracts from all nonfederal acute care hospitals in Washington State linked to death certificates were evaluated. Patients > or =45 yr old with prior PTCA who underwent noncardiac surgery from 1987 to 1993 were matched by age, sex, surgery type, and discharge year to 686 patients with CAD and to 2155 normal controls (no CAD). We compared risk for adverse cardiac outcomes (death, myocardial infarction, angina, congestive heart failure, malignant dysrhythmia, cardiogenic shock, coronary artery bypass graft, or PTCA) within 30 days. Patients with PTCA had twice the risk of adverse cardiac outcome as normal controls (odds ratio [OR] 1.98; P < 0.001), with a higher risk of angina (OR 7.84), congestive heart failure (OR 2.06), and myocardial infarction (OR 3.86) but a lower risk of death (OR 0.46; P < 0.001). Patients with PTCA had half the risk of adverse cardiac outcome as patients with CAD (OR 0.50; P < 0.001), including less risk of angina (OR 0.51) and congestive heart failure (OR 0.40; P < 0.001), but no difference in myocardial infarction (P = 0.304) or death (P = 0.436). No difference was found between 142 patients with recent PTCA (< or =90 days before noncardiac surgery) matched to patients with CAD (OR 0.90; P = 0.396). Patients revascularized by PTCA >90 days before noncardiac surgery seem to have a lower risk of poor outcome than nonrevascularized patients, although not as low as normal controls. For recent PTCA patients, the lack of difference compared with CAD patient outcomes requires a larger sample size for verification. Present findings do not lend support to a role for prophylactic PTCA to improve noncardiac surgery outcomes. This investigation did not control for CAD severity, medical management, or comorbidities. Study of these factors is needed before the clinical implications of PTCA for noncardiac surgical risk can be completely assessed. IMPLICATIONS: Hospital records showed patients with prior percutaneous transluminal coronary angioplasty were twice as likely as healthy patients to have an adverse cardiac outcome after noncardiac surgery, although their risk was reduced by half compared with patients with untreated coronary artery disease. Further study of the role of percutaneous transluminal coronary angioplasty in modulating noncardiac surgery risk is needed.

Aged↗
PubMed1999

Awareness during anesthesia: a closed claims analysis.

BACKGROUND: Awareness during general anesthesia is a frightening experience, which may result in serious emotional injury and post-traumatic stress disorder. We performed an in-depth analysis of cases from the database of the American Society of Anesthesiologists Closed Claims Project to explore the contribution of intraoperative awareness to professional liability in anesthesia. METHODS: The database of the Closed Claims Project is composed of closed US malpractice claims that have been collected in a standardized manner. All claims for intraoperative awareness were reviewed by the reviewers to identify patterns of causation and standard of care. Logistic regression analysis was used to identify independent patient and anesthetic factors associated with claims for recall during general anesthesia compared to other general anesthesia malpractice claims. RESULTS: Awareness claims accounted for 79 (1.9%) of 4,183 claims in the database, including 18 claims for awake paralysis, i.e., the inadvertent paralysis of an awake patient, and 61 claims for recall during general anesthesia, ie., recall of events while receiving general anesthesia. The majority of awareness claims involved women (77%), younger than 60 yr of age (89%), American Society of Anesthesiologists physical class I-II (68%), who underwent elective surgery (87%). Most (94%) claims for awake paralysis represented substandard care involving errors in labeling and administration, whereas care was substandard in only 43% of the claims for recall during general anesthesia (P < 0.001). Claims for recall during general anesthesia were more likely to involve women (odds ratio [OR] = 3.08, 95% confidence interval [CI] = 1.58, 6.06) and anesthetic techniques using intraoperative opioids (OR = 2.12, 95% CI = 1.20, 3.74), intraoperative muscle relaxants (OR = 2.28, 95% CI = 1.22, 4.25), and no volatile anesthetic (OR = 3.20, 95% CI = 1.88, 5.46). CONCLUSIONS: Deficiencies in labeling and vigilance were common causes for awake paralysis. Claims for recall during general anesthesia were more likely in women and with nitrous-narcotic-relaxant techniques.

Adult↗
PubMed1999

Nerve injury associated with anesthesia: a closed claims analysis.

BACKGROUND: Nerve injury associated with anesthesia is a significant source of morbidity for patients and liability for anesthesiologists. To identify recurrent and emerging patterns of injury we analyzed the current American Society of Anesthesiologists (ASA) Closed Claims Project Database and performed an in-depth analysis of claims for nerve injury that were entered into the database since the authors' initial report of the subject. METHODS: The ASA Closed Claims Database is a standardized collection of case summaries derived from the closed claims files of professional liability insurance companies. Claims for nerve injury that were not included in the authors' 1990 report were reviewed in-depth. RESULTS: Six hundred seventy (16% of 4,183) claims were for anesthesia-related nerve injury. The most frequent sites of injury were the ulnar nerve (28%), brachial plexus (20%), lumbosacral nerve root (16%), and spinal cord (13%). Ulnar nerve (85%) injuries were more likely to have occurred in association with general anesthesia, whereas spinal cord (58%) and lumbosacral nerve root (92%) injuries were more likely to occur with regional techniques. Ulnar nerve injury occurred predominately in men (75%) and was also more apt to have a delayed onset of symptoms (62%) than other nerve injuries. Spinal cord injuries were the leading cause of claims for nerve injury that occurred in the 1990s. CONCLUSION: New strategies for prevention of nerve damage cannot be recommended at this time because the mechanism for most injuries, particularly those of the ulnar nerve, is not apparent.

Adolescent↗
PubMed1999

Trends in quality of anesthesia care associated with changing staffing patterns, productivity, and concurrency of case supervision in a teaching hospital.

BACKGROUND: The authors used continuous quality improvement (CQI) program data to investigate trends in quality of anesthesia care associated with changing staffing patterns in a university hospital. METHODS: The monthly proportion of cases performed by solo attending anesthesiologists versus attending-resident teams or attending-certified registered nurse anesthetist (CRNA) teams was used to measure staffing patterns. Anesthesia team productivity was measured as mean monthly surgical anesthesia hours billed per attending anesthesiologist per clinical day. Supervisory ratios (concurrency) were measured as mean monthly number of cases supervised concurrently by attending anesthesiologists. Quality of anesthesia care was measured as monthly rates of critical incidents, patient injury, escalation of care, operational inefficiencies, and human errors per 10,000 cases. Trends in quality at increasing productivity and concurrency levels from 1992 to 1997 were analyzed by the one-sided Jonckheere-Terpstra test. RESULTS: Productivity was positively correlated with concurrency (r = 0.838; P<0.001). Productivity levels ranged from 10 to 17 h per anesthesiologist per clinical day. Concurrency ranged from 1.6 to 2.2 cases per attending anesthesiologist. At higher productivity and concurrency levels, solo anesthesiologists conducted a smaller percentage of cases, and the proportion of cases with CRNA team members increased. The patient injury rate decreased with increased productivity levels (P = 0.002), whereas the critical incident rate increased (P = 0.001). Changes in operational inefficiency, escalation of care, and human error rates were not statistically significant (P = 0.072, 0.345, 0.320, respectively). CONCLUSIONS: Most aspects of quality of anesthesia care were apparently not effected by changing anesthesia team composition or increased productivity and concurrency. Only team performance was measured; the role of individuals (attending anesthesiologist, resident, or CRNA) in quality of care was not directly measured. Further research is needed to explain lower patient injury rates and increases in critical incident reporting at higher concurrency and productivity levels.

Anesthesia↗
PubMed1999

Airway injury during anesthesia: a closed claims analysis.

BACKGROUND: Airway injury during general anesthesia is a significant source of morbidity for patients and a source of liability for anesthesiologists. To identify recurrent patterns of injury, the authors analyzed claims for airway injury in the American Society of Anesthesiologists (ASA) Closed Claims Project database. METHODS: The ASA Closed Claims database is a standardized collection of case summaries derived from professional liability insurance companies closed claims files. All claims for airway injury were reviewed in depth and were compared to other claims during general anesthesia. RESULTS: Approximately 6% (266) of 4,460 claims in the database were for airway injury. The most frequent sites of injury were the larynx (33%), pharynx (19%), and esophagus (18%). Injuries to the esophagus and trachea were more frequently associated with difficult intubation. Injuries to temporomandibular joint and the larynx were more frequently associated with nondifficult intubation. Injuries to the esophagus were more severe and resulted in a higher payment to the plaintiff than claims for other sites of airway injury. Difficult intubation (odds ratio = 4.53, 95% confidence interval [CI] = 2.36, 8.71), age older than 60 yr (odds ratio = 2.97, 95% CI = 1.51, 5.87), and female gender (odds ratio = 2.43, 95% CI = 1.09, 5.42) were associated with claims for pharyngoesophageal perforation. Early signs of perforation, e.g., pneumothorax and subcutaneous emphysema, were present in only 51% of perforation claims, whereas late sequelae, e.g., retropharyngeal abscess and mediastinitis, occurred in 65%. CONCLUSION: Patients in whom tracheal intubation has been difficult should be observed for and told to watch for the development of symptoms and signs of retropharyngeal abscess, mediastinitis, or both.

Adolescent↗
PubMed1997

Adverse anesthetic outcomes arising from gas delivery equipment: a closed claims analysis.

BACKGROUND: Anesthesia gas delivery equipment is a potentially important source of patient injury. To better define the contribution of gas delivery equipment to professional liability in anesthesia, the authors conducted an in-depth analysis of cases from the database of the American Society of Anesthesiologists Closed Claims Project. METHODS: The database of the Closed Claims Project is composed of closed US malpractice claims that have been collected in a standardized manner. All claims resulting from the use of gas delivery equipment were reviewed for recurrent patterns of injury. RESULTS: Gas delivery equipment was associated with 72 (2%) of 3,791 claims in the database. Death and permanent brain damage accounted for almost all adverse outcomes (n = 55, 76%). Equipment misuse was defined as fault or human error associated with the preparation, maintenance, or deployment of a medical device. Equipment failure was defined as unexpected malfunction of a medical device, despite routine maintenance and previous uneventful use. Misuse of equipment (n = 54, 75%) was three times more common than equipment failure (n = 17, 24%). Misconnects and disconnects of the breathing circuit made the largest contribution to injury (n = 25, 35%). Reviewers judged that 38 of 72 claims (53%) could have been prevented by pulse oximetry, capnography, or a combination of these two monitors. Overall, 56 of 72 gas delivery claims (78%) were deemed preventable with the use or better use of monitors. The year of occurrence for claims involving gas delivery equipment ranged from 1962 to 1991 and did not differ significantly from claims involving other adverse respiratory events. CONCLUSIONS: Claims associated with gas delivery equipment are infrequent but severe and continue to occur in the 1990s. Educational and preventive strategies that focus on equipment misuse and breathing circuit configuration may have the greatest potential for enhancing the safety of anesthesia gas delivery equipment.

Anesthesiology↗
PubMed1997

Cost-effective reduction of neuromuscular-blocking drug expenditures.

BACKGROUND: Anesthetic drug expenditures have been a focus of cost-containment efforts. The aim of this study was to determine whether expenditures for neuromuscular-blocking agents could be reduced without compromising outcome, and to determine whether such a cost-effective pattern of neuromuscular blocker use could be sustained. METHODS: Education, practice guidelines, and paperwork barriers were used to persuade anesthesiologists to substitute low-cost neuromuscular-blocking drugs (pancuronium or a metocurine-pancuronium combination) for a more costly neuromuscular-blocking drug (vecuronium). Neuromuscular-blocking drug use in all patients during a historical control period (6 months; n = 4,804) was compared with that during two consecutive 1-yr periods of intervention (n = 9,761/n = 10,695). Expenditures for vecuronium and for all neuromuscular-blocking drugs were compared for the control and intervention periods. The rate of complications related to neuromuscular-blocking drugs was determined by an ongoing continuous quality improvement program. RESULTS: Vecuronium use decreased by 76% during the first and second yr of intervention, compared with the historical period (P < 0.01). The cost of neuromuscular-blocking drugs decreased by 31% (P < 0.01) and 47% (P < 0.01) for the first and second yr, respectively. The complication rate related to neuromuscular-blocking drugs was 0.081% in the historical period and 0.11% and 0.093% during the intervention periods (P = 0.29 and 0.41). CONCLUSION: Practice guidelines, education, and paperwork barriers used together substantially reduced the expenditures for neuromuscular-blocking drugs for 2 yr without adversely affecting clinical outcome.

Adult↗
PubMed1996

Variation in expert opinion in medical malpractice review.

BACKGROUND: Expert opinion in medical malpractice is a form of implicit assessment, based on unstated individual opinion. This contrasts with explicit assessment processes, which are characterized by criteria specified and stated before the assessment. Although sources of bias that might hinder the objectivity of expert witnesses have been identified, the effect of the implicit nature of expert review has not been firmly established. METHODS: Pairs of anesthesiologist-reviewers independently assessed the appropriateness of care in anesthesia malpractice claims. With potential sources of bias eliminated or held constant, the level of agreement was measured. RESULTS: Thirty anesthesiologists reviewed 103 claims. Reviewers agreed on 62% of claims and disagreed on 38%. They agreed that care was appropriate in 27% and less than appropriate in 32%. Chance-corrected levels of agreement were in the poor-good range (kappa = 0.37; 95% CI = 0.23 to 0.51). CONCLUSIONS: Divergent opinion stemming from the implicit nature of expert review may be common among objective medical experts reviewing malpractice claims.

Anesthesiology↗
PubMed1995

Changes in clinical practice in response to reductions in reimbursement: physician autonomy and resistance to bureaucratization.

This analysis of field data from 1991 and 1992 examines the process of joint decision making between cardiothoracic surgeons and anesthesiologists in a U.S. hospital as they made changes in clinical practice in response to reimbursement reductions. Although these physicians have concurrent responsibility for patient care in the operating room, their domains of authority are ambiguous. Much clinical decision making was found to be based on charismatic authority. In making practice changes, cardiothoracic surgeons maintained all and anesthesiologists most of their charismatic authority, expanding the conventional range of physician practice while prescribing specific practices for nonphysician providers. Ambiguity of joint physician authority over patient care was left unresolved, and the economic goals of the practice changes were not realized. Physicians resisted the bureaucratic claim to authority rooted in cost accounting by resorting to the need for nonroutinized clinical decisions.

Anesthesiology↗
PubMed1994

Burns from warming devices in anesthesia. A closed claims analysis.

BACKGROUND: Prevention of hypothermia is an important aspect of anesthetic management. Methods used for its prevention may, however, cause cutaneous burns. We reviewed the American Society of Anesthesiologists (ASA) Closed Claims Project database to determine if there were recurrent patterns of injury arising from intraoperative warming methods. METHODS: The ASA Closed Claims Project database is a collection of closed malpractice claims that have been reviewed in a standardized format. All claims for burns were reviewed. RESULTS: Among the 3,000 total claims there were 54 burns, of which 28 resulted from materials or devices used to warm patients. Intravenous fluid bags or bottles warmed in an oven and then applied to the patient's skin were responsible for 18 of the 28 (64%) burns associated with warming devices. These burns from intravenous fluid bags or bottles occurred in predominantly healthy (ASA physical status 1-2) young (age 38 +/- 17 yr, mean +/- standard deviation) women undergoing routine gynecologic or peripheral orthopedic surgery under general anesthesia. Of the eight burns from electrically powered warming equipment, five resulted from circulating-water mattresses. CONCLUSIONS: Intravenous fluid bags or bottles warmed in an operating room oven represent a hazard to anesthetized patients. Because intravenous fluid bags or bottles are not an efficient method of patient warming, there seems to be little justification for their use.

Adult↗
PubMed1994

Linking process and outcome of care in a continuous quality improvement program for anesthesia services.

We developed a continuous quality improvement (CQI) program for anesthesia services based on self-reporting of critical incidents and negative outcomes through a dichotomous (yes/no) response on the anesthesia record. Immediate case investigation provides data for systematic peer review of anesthesia management. Trend analysis of the database of critical incidents and negative outcomes identifies opportunities for improvement. The CQI program resulted in the reporting of nearly twice as many problems related to anesthesia management (5% of all anesthetics) as did the checklist it replaced (2.7%). Escalation of patient care (3.2%) and operational inefficiencies (2.2%) were more common than patient injury (1.5% of all anesthetics). Among the 537 cases with anesthesia management problems were 119 human errors and equipment problems (22%). Regional nerve blocks and airway management represented the most common problem areas. Improvement in anesthesia services was made through prompt implementation of strategies for problem prevention devised by the practitioners themselves through peer review, literature review, and clinical investigations.

Anesthesia Department, Hospital↗
PubMed1993

A comparison of pediatric and adult anesthesia closed malpractice claims.

BACKGROUND: Since 1985, the Committee on Professional Liability of the American Society of Anesthesiologists has evaluated closed anesthesia malpractice claims. This study compared pediatric and adult closed claims with respect to the mechanisms of injury, outcome, the costs, and the role of care judged to be substandard. METHODS: Using a standardized form and method developed for analysis of closed claims, the American Society of Anesthesiologists Closed Claims Data Base was used to compare pediatric with adult anesthesia-related adverse events. RESULTS: Of the 2,400 total claims, 238 (10%) were in the pediatric age group (15 yr of age or younger). The pediatric claims presented a different distribution of damaging events compared with that of adults. In particular, respiratory events were more common among pediatric claims (43% versus 30% in adult claims; P < or = 0.01). The mortality rate was greater in the pediatric claims (50% versus 35% in adult claims; P < or = 0.01), anesthetic care more often was judged less than appropriate (54% versus 44% in adult claims; P < or = 0.01), the complications more frequently were thought to be preventable with better monitoring (45% versus 30% in adult claims; P < or = 0.01), and the distribution of payments to the plaintiff was different (median payment, $111,234 versus $90,000 in adult claims; P < or = 0.05). Many of the differences between pediatric and adult claims were explained by a higher prevalence of patient injury caused by inadequate ventilation in the pediatric claims (20% versus 9% in adult claims; P < or = 0.01). In pediatric compared with adult inadequate ventilation claims, poor medical condition and/or obesity (6% versus 41%; P < or = 0.01) were uncommon associated factors. Cyanosis (49%) and/or bradycardia (64%) often preceded cardiac arrest in pediatric claims related to inadequate ventilation, resulting in death (70%) or brain damage (30%) in previously healthy children. Although clinical clues suggested hypoxemia as a common mechanism of injury, the files did not contain enough information to explain the genesis of hypoxemia in these claims. CONCLUSIONS: Comparison of adult and pediatric closed claims revealed a large prevalence of respiratory related damaging events--most frequently related to inadequate ventilation. In the opinion of the reviewers, 89% of the pediatric claims related to inadequate ventilation could have been prevented with pulse oximetry and/or end tidal CO2 measurement. However, pulse oximetry appeared to prevent poor outcome in only one of seven claims in which pulse oximetry was used and could possibly have done so.

Adolescent↗
PubMed1992

Eye injuries associated with anesthesia. A closed claims analysis.

Claims against anesthesiologists for eye injuries were analyzed as part of the ASA Closed Claims Project. Eye injury occurred in 3% of all claims in the database (71 of 2,046). The payment frequency for eye injury claims was higher than that for non-eye injury claims (70% vs. 56%; P less than or equal to 0.05). The median cost of eye injury claims was less than that for other claims ($24,000 vs. $95,000; P less than or equal to 0.01). Two distinct subsets were identified. The first was characterized by corneal abrasion during general anesthesia (25 of 71 claims; 35%). Claims for corneal abrasion were characterized by low incidence of permanent injury (16%) and low median payment ($3,000). Reviewers were able to identify a mechanism of injury in only 20% of claims for corneal abrasion. The second subset of eye injury was characterized by patient movement during ophthalmologic surgery (21 of 71; 30%). Blindness was the outcome in all cases. Sixteen of the claims involving movement occurred during general anesthesia, and 5 occurred during monitored anesthesia care. The median payment for claim involving movement was 10 times greater than for non-movement claims ($90,000 vs. $9,000; P less than or equal to 0.01). Anesthesiologist reviewers deemed the care rendered in the general anesthesia "movement" claims as meeting standards in only 19% of claims. From the perspective of patient safety, as well as risk management, these data suggest two specific needs: research directed at better understanding of the etiology of corneal abrasion and clinical strategies designed to assure patient immobility during ophthalmic surgery.

Adult↗