Karen L. Posner

Adverse respiratory events in anesthesia: a closed claims analysis.

Adverse outcomes associated with respiratory events constitute the single largest class of injury in the American Society of Anesthesiology Closed Claims Study (522 of 1541 cases; 34%). Death or brain damage occurred in 85% of cases. The median cost of settlement or jury award was +200,000. Most outcomes (72%) were considered preventable with better monitoring. Three mechanisms of injury accounted for three-fourths of the adverse respiratory events: inadequate ventilation (196; 38%), esophageal intubation (94; 18%), and difficult tracheal intubation (87; 17%). Inadequate ventilation was used to describe claims in which it was evident that insufficient gas exchange had produced the adverse outcome, but it was not possible to identify the exact cause. This group was characterized by the highest proportion of cases in which care was considered substandard (90%). The esophageal intubation group was notable for a recurring diagnostic failure: in 48% of cases where auscultation of breath sounds was performed and documented, this test led to the erroneous conclusion that the endotracheal tube was correctly located in the trachea. Claims for difficult tracheal intubation were distinguished by a comparatively small proportion of cases (36%) in which the outcome was considered preventable with better monitoring. A better understanding of respiratory risks may require investigative protocols that initiate data collection immediately upon the recognition of a critical incident or adverse outcome.

Management of the Difficult Airway

BACKGROUND The purpose of this study was to identify the patterns of liability associated with malpractice claims arising from management of the difficult airway. METHODS Using the American Society of Anesthesiologists Closed Claims database, the authors examined 179 claims for difficult airway management between 1985 and 1999 where a supplemental data collection tool was used and focused on airway management, outcomes, and the role of the 1993 Difficult Airway Guidelines in litigation. Chi-square tests and multiple logistic regression analysis compared risk factors for death or brain damage (death/BD) from two time periods: 1985-1992 and 1993-1999. RESULTS Difficult airway claims arose throughout the perioperative period: 67% upon induction, 15% during surgery, 12% at extubation, and 5% during recovery. Death/BD with induction of anesthesia decreased in 1993-1999 (35%) compared with 1985-1992 (62%; P < 0.05; odds ratio, 0.26; 95% confidence interval, 0.11-0.63; P = 0.003). In contrast, death/BD associated with other phases of anesthesia did not significantly change over the time periods. The odds of death/BD were increased by the development of an airway emergency (odds ratio, 14.98; 95% confidence interval, 6.37-35.27; P < 0.001). During airway emergencies, persistent intubation attempts were associated with death/BD (P < 0.05). Since 1993, the Airway Guidelines were used to defend care (8%) and criticize care (3%). CONCLUSIONS Death/BD in claims from difficult airway management associated with induction of anesthesia but not other phases of anesthesia decreased in 1993-1999 compared with 1985-1992. Development of additional management strategies for difficult airways encountered during maintenance, emergence, or recovery from anesthesia may improve patient safety.

Anesthesia-related cardiac arrest in children: initial findings of the Pediatric Perioperative Cardiac Arrest (POCA) Registry.

Background The Pediatric Perioperative Cardiac Arrest (POCA) Registry was formed in 1994 in an attempt to determine the clinical factors and outcomes associated with cardiac arrest in anesthetized children. Methods Institutions that provide anesthesia for children are voluntarily enrolled in the POCA Registry. A representative from each institution provides annual institutional demographic information and submits anonymously a standardized data form for each cardiac arrest (defined as the need for chest compressions or as death) in anesthetized children 18 yr of age or younger. Causes and factors associated with cardiac arrest are analyzed. Results In the first 4 yr of the POCA Registry, 63 institutions enrolled and submitted 289 cases of cardiac arrest. Of these, 150 arrests were judged to be related to anesthesia. Cardiac arrest related to anesthesia had an incidence of 1.4 ± 0.45 (mean ± SD) per 10,000 instances of anesthesia and a mortality rate of 26%. Medication-related (37%) and cardiovascular (32%) causes of cardiac arrest were most common, together accounting for 69% of all arrests. Cardiovascular depression from halothane, alone or in combination with other drugs, was responsible for two thirds of all medication-related arrests. Thirty-three percent of the patients were American Society of Anesthesiologists physical status 1–2; in this group, 64% of arrests were medication-related, compared with 23% in American Society of Anesthesiologists physical status 3–5 patients (P < 0.01). Infants younger than 1 yr of age accounted for 55% of all anesthesia-related arrests. Multivariate analysis demonstrated two predictors of mortality: American Society of Anesthesiologists physical status 3–5 (odds ratio, 12.99; 95% confidence interval, 2.9–57.7), and emergency status (odds ratio, 3.88; 95% confidence interval, 1.6–9.6). Conclusions Anesthesia-related cardiac arrest occurred most often in patients younger than 1 yr of age and in patients with severe underlying disease. Patients in the latter group, as well as patients having emergency surgery, were most likely to have a fatal outcome. The identification of medication-related problems as the most frequent cause of anesthesia-related cardiac arrest has important implications for preventive strategies.

Unexpected cardiac arrest during spinal anesthesia: a closed claims analysis of predisposing factors.

Fourteen cases of sudden cardiac arrest in healthy patients who received spinal anesthesia were discovered in a preliminary review of 900 closed insurance claims for major anesthetic mishaps. All patients were resuscitated from the intraoperative cardiac arrest, but six suffered such severe neurologic injury that they died in hospital. Of the eight survivors, only one exhibited sufficient neurologic recovery to allow independence in daily self-care. In view of the unexpected nature of the cardiac arrests, as well as the ultimate severity of injury, these cases were analyzed in detail to determine whether there were recurring patterns of management that may have contributed to the occurrence or outcome of these anesthetic mishaps. Two patterns were identified. The first was the intraoperative use of sufficient sedation to produce a comfortable-appearing, sleep-like state in which there was no spontaneous verbalization. Cyanosis frequently heralded the onset of cardiac arrest in patients exhibiting this degree of sedation, suggesting that unappreciated respiratory insufficiency may have played an important role. The second pattern appeared to be an inadequate appreciation of the interaction between sympathetic blockade during high spinal anesthesia and the mechanisms of cardiopulmonary resuscitation. Prompt augmentation of central venous filling through the use of a potent α-agonist and positional change might have improved organ perfusion, shortened the duration of cardiac arrest, and lessened the degree of neurologic damage.

Anesthesia-Related Cardiac Arrest in Children: Update from the Pediatric Perioperative Cardiac Arrest Registry

BACKGROUND:The initial findings from the Pediatric Perioperative Cardiac Arrest (POCA) Registry (1994–1997) revealed that medication-related causes, often cardiovascular depression from halothane, were the most common. Changes in pediatric anesthesia practice may have altered the causes of cardiac arrest in anesthetized children. METHODS:Nearly 80 North American institutions that provide anesthesia for children voluntarily enrolled in the Pediatric Perioperative Cardiac Arrest Registry. A standardized data form for each perioperative cardiac arrest in children ≤18 yr of age was submitted anonymously. We analyzed causes of anesthesia-related cardiac arrests and related factors in 1998–2004. RESULTS:From 1998 to 2004, 193 arrests (49%) were related to anesthesia. Medication-related arrests accounted for 18% of all arrests, compared with 37% from 1994 to 1997 (P < 0.05). Cardiovascular causes of cardiac arrest were the most common (41% of all arrests), with hypovolemia from blood loss and hyperkalemia from transfusion of stored blood the most common identifiable cardiovascular causes. Among respiratory causes of arrest (27%), airway obstruction from laryngospasm was the most common cause. Vascular injury incurred during placement of central venous catheters was the most common equipment-related cause of arrest. The cause of arrest varied by phase of anesthesia care (P < 0.01). Cardiovascular and respiratory causes occurred most commonly in the surgical and postsurgical phases, respectively. CONCLUSIONS:A reduction in the proportion of arrests related to cardiovascular depression due to halothane may be related to the declining use of halothane in pediatric anesthetic practice. The incidence of the most common remaining causes of arrest in each category may be reduced through preventive measures.

Nerve injury associated with anesthesia.

The authors examined the American Society of Anesthesiologists Closed Claims Study database to define the role of nerve damage in the overall spectrum of anesthesia-related injury that leads to litigation. Of 1,541 claims reviewed, 227 (15%) were for anesthesia-related nerve injury. Ulnar neuropathy represented one-third of all nerve injuries and was the most frequent nerve injury. Less-frequent sites of nerve injury were the brachial plexus (23%) and the lumbosacral nerve roots (16%). In a large proportion of cases, the exact mechanism of injury was unclear despite evidence of intensive investigation in the claim files. Median payment for nerve damage claims involving disabling injury was

Awareness during anesthesia: a closed claims analysis.

56,000, which was significantly lower than the

Airway injury during anesthesia: a closed claims analysis.

225,000 median payment for claims for disabling injury not involving nerve damage (P less than 0.01). The closed claims reviewers judged that the standard of care had been met significantly more often in claims involving nerve damage than in claims not involving nerve damage. The authors conclude that nerve damage is a significant source of anesthesia-related claims but that the exact mechanism of nerve injury is often unclear. In particular, ulnar nerve injuries seemed to occur without identifiable mechanism.

The american society of anesthesiologists postoperative visual loss registry : Analysis of 93 spine surgery cases with postoperative visual loss

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.

Injury and liability associated with monitored anesthesia care: 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.