Disclosures. Closed Claims Reports: Review of Anesthetic Complications. ASA Closed Claims Database. Outline

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1 Closed Claims Reports: Review of Anesthetic Complications Disclosures Funded by NHLBI & Hamilton Endowment Funds (UCSF Department of Anesthesia). Jae-Woo Lee, MD Associate Professor in Residence University of California San Francisco Outline Background to ASA Closed Claims Database Perioperative Nerve Injury Postoperative Visual Loss Registry Liability Association with Subspecialties (i.e. Chronic Pain, OB and Pediatrics) ASA Closed Claims Database Background: Database started in 1984 to study anesthesia injuries to improve patient safety and prevent injury. Adverse anesthesia malpractice insurance claim files of >35 professional liability companies in the United States, representing 1/3 of all practicing anesthesiologists. Now contains 8954 claims with 5230 claims since Claims for damage to teeth/dentures or files with inadequate information were excluded (resulting in 27% rejection rate). Metzner et al. Best Practice & Research Clinical Anaesthesiology 25: ,

2 ASA Closed Claims Database Strengths and Limitations: Able to study a large collection of relatively rare anesthetic events. However, the incidence and risk of anesthetic-related adverse events are unknown due to the absence of numerator data regarding the total number of adverse events and the denominator data for the total number of anesthetic procedures performed. No control groups for comparison. Useful for study pattern of injury and identify risk factors to improve patient safety. Trends Claims for death or permanent brain damage decreased from 44% of claims between to 31% of claims from In 1975, death or permanent brain damage accounted for 56%. In 2000, death or permanent brain damage accounted for 27%. Of the underlying mechanisms, respiratory related events decreased while cardiovascular events increased. Metzner et al. Best Practice & Research Clinical Anaesthesiology 25: , Cheney et al. Anesthesiology 105:1081-6, Trends While claims for surgical anesthesia involving death and permanent brain damage has declined: Claims for acute and chronic pain has increased. Claims for MAC anesthesia has increased. MAC Anesthesia Claims: Claims from 1990 to Involved older patients with higher ASA classification compared to GA or RA. Common surgical procedures involved elective eye surgery (21%) or facial plastic surgery (26%). 40% of claims involved death or permanent brain damage, with respiratory depression the most frequent cause. 17% of cases involved burn injuries or OR fires. Nearly 50% of cases were judged preventable with additional or better monitoring. Cheney et al. Anesthesiology 105:1081-6, Metzner et al. Best Practice & Research Clinical Anaesthesiology 25: , Bhananker et al. Anesthesiology 104:228-34,

3 MAC Anesthesia Claims: Perioperative Nerve Injuries Low incidence (Approx. 0.03% at the U of Michigan). Injuries from stretch, ischemia and compression. Injury from Peripheral Nerve Blocks. Bhananker et al. Anesthesiology 104:228-34, Cheney et al. Anesthesiology 90:1062-9, Welch et al. Anesthesiology 111:464-6, Perioperative Nerve Injuries: Ulnar Neuropathy (25%): Incidence < 0.5% of non-cardiac surgeries. In ASA Closed Claims Project: Only 9% associated with known causes. 27% of cases, padding to the elbow was explicitly stated. 7% of cases occurred during MAC with spinal, epidural or local. Etiology of nerve palsy is multi-factorial. Cheney et al. Anesthesiology 90:1062-9, Lee & Cassorla, Basics of Anesthesia, 6 th Edition, Chapt 19, Editors. Miller and Pardo. 3

4 Ulnar Neuropathy (cont.): Warner et al: 57% experience palsy > 24 hrs after surgery. 70% male, 9% bilateral. Predominance of male may be anatomical. No association with patient position or anesthetic technique. Brachial Plexus (19%): Etiology: Stretching or compression due to long superficial course in axilla between two points of fixation, the vertebra and the axilla fascia in association with the mobile clavicle and humerus. Associated predominantly with cardiac surgery (4.9%) (median sternotomy) vs. non-cardiac surgery (0.02%). Other risk factors (DM, Vitamin def., ETOH, Tobacco, Cancer, etc.) yet to be substantiated. ASA Closed Claims Project: 10% related to positioning: 50% involving shoulder braces in Trendelenburg position, malposition of the arms, sustained neck extension. 16% associated with nerve block, particularly the axillary block. Warner MA. Mayo Clinic Proc. 73:567-74, Brachial Plexus (19%): Recommendation for Prevention of Nerve Injury: Britt & Gordon Can Anaesth Soc J 11:514-36, Lee & Cassorla, Basics of Anesthesia, 6 th Edition, Chapt 19, Editors. Miller and Pardo 4

5 Nerve Injury from Peripheral Nerve Blocks: Analyses of Closed Claims Database since 1990: Nerve Injury from Regional Anesthesia: Represented 2% of claims in the acute pain and surgical setting (neuraxial, eye or chronic pain blocks were excluded). 69% of patients were ASA I-II 64% involved outpatient procedures. 71%, regional anesthesia for the surgical procedure, 29% acute pain procedure. 68% of peripheral nerve block claims were associated with temporary or non-disabling injuries. 16% permanent/disabling injuries, 5% involved with brain damage and 11% with death. Lee et al. Int Anesth Clinics 49:56-67, Peripheral nerve blocks associate brain damage or death: local anesthetic toxicity (seizures/arrhythmia), prolonged hypotension (beach chair), hypoxia. No claims associated with ultrasound-guided blocks. Lee et al. Int Anesth Clinics 49:56-67, Key Points: Peripheral nerve injury, although rare, represents >18% of cases in the ASA Closed Claims Database, second only to death. It may result from patient positioning. The mechanisms of injury are stretching, compression, and ischemia. Ulnar neuropathy is the most common postoperative nerve injury, followed by injury to the brachial plexus, lumbosacral nerve roots, and spinal cord. Not all postoperative neuropathies, including ulnar neuropathy, are currently explainable and may not be entirely preventable. Many postoperative ulnar nerve deficits do not appear to be related to intraoperative patient position as they appear days after surgery. The ASA issued a Practice Advisory in 2000 for the prevention of perioperative peripheral neuropathies. However only 6 of 509 studies reviewed met the standard for a scientifically proven relationship between intervention and outcome. Perioperative Eye Injury or Visual Loss: Incidence 0.056% or 4% of ASA Closed Claims Database. Closed Claims Project Database: Corneal abrasion most common from (31%). Optic Nerve injury most common from (38%) Significant increase in median payment over these two periods, primarily related to permanent nature of the injuries to the optic nerve and central retinal artery or vein occlusion in association with spine surgery. Lee et al. Anesthesiology A2058,

6 Perioperative Visual Loss: Patient risk factors: Older age, Hypertension, Diabetes, Atherosclerosis, Morbid Obesity, Tobacco. Intraoperative risk factors: Prolonged or induced hypotension (>40 min below baseline 30 min), Use of vasopressors, Long duration of surgery, Excessive blood loss or crystalloid use, Anemia or hemodilution, Prone positioning (Spine surgery), Cardiac surgery (Embolism & Hypo-perfusion). Postoperative Visual Loss (POVL) Registry Since 1999, 131 cases reported. 73% involved spine surgeries, 9% involved CPB. Spinal fusion surgery more than doubled from Among spine surgeries (n = 93), 89% ischemic optic neuropathy (ION, predominantly posterior) and 11% central arterial occlusion (CRAO). Patients with ION were healthy (64%, ASA I & II) and 73% male. 66% of ION were bilateral, of which 42% of ION recovered vision. Lee et al. Anesthesiology 105: 652-9, Postoperative Visual Loss Study Group. Anesthesiology 116:15-24, POVL Among Spine Patients In a multi-center case control design study, multivariate risk factors for ION after prone spine surgery compared to patients without ION: Male sex, OR 2.53 ( ) Obesity, OR 2.83 ( ) Wilson frame, OR 4.3 ( ) Anesthesia duration, OR per 1 h, OR 1.39 ( ) EBL, OR per 1 L, OR 1.34 ( ) Colloid as a percent of non-blood replacement, OR per 5%, OR 0.67 ( ). Key Points: Based on the Closed Claims Database since 1995, the most common eye injuries are no longer corneal abrasions but optic nerve injury. Postoperative visual loss is a rare but devastating complication that is associated with the prone position and spine surgery. It s causes are multifactorial and incompletely understood. Ischemic optic neuropathy is the most common etiology of postoperative visual loss. In prone time surgery, risks factors for ION include male sex, obesity, the use of the Wilson frame, anesthetic duration, EBL and colloid use as % of non-blood volume infused. Lee et al. Anesthesiology 105: 652-9, Postoperative Visual Loss Study Group. Anesthesiology 116:15-24,

7 Chronic Pain Management: Claims arising from chronic pain management have increased over time, accounting for 10% of anesthesia malpractice claims in the 1990s. Chronic Pain Management: Nerve injury and pneumothorax were the common complications cited. 40% of all claims involved epidural steroid injections; death and brain death were more common with epidural injections when steroids were combined with local anesthetics. From , payments for claims from chronic pain management was similar to those from surgical/obstetric cases, perhaps reflexing an increase in severity of the injury. Fitzgibbon et al. Anesthesiology 100: , Fitzgibbon et al. Anesthesiology 100: , Chronic Pain Management (Cervical Spine): From , claims from cervical intervention represented 22% of all chronic pain management claims. 59% experienced spinal cord damage with direct needle trauma (31%) as the predominant cause. General anesthesia or sedation was used in 67% of cervical procedures associated with spinal cord injury compared to only 19% of procedures without spinal cord injury. 25% who developed spinal cord injuries were not responsive during the procedure. Rathmell et al. Anesthesiology 114: , Chronic Pain Management (Medication): From , 17% of chronic non-cancer pain claims were from medication management issues. Compared to other chronic pain claims, patients tended to be younger men with back pain. Death was the most common outcome in medical management claims (57% compared to 9% for other chronic pain claims). Factors associated with death included long-acting opioids, other psychoactive mediations and 3 factors associated with medication misuse. Most claims (82%) involved patients who did not cooperate in their care (69%) or inappropriate medication management by the physician (59%). Fitzgibbon et al. Anesthesiology 112:948-56,

8 Chronic Pain Management (Medication): Most common forms of inappropriate medication management were inadequate communication with other prescribing physicians and inadequate monitoring of medication compliance. Obstetric Anesthesia: Since 1990, maternal death and newborn death/brain damage, which were the most common complications, decreased significantly. Associated with a decrease in respiratory events (24% to 4%) such as inadequate oxygenation/ventilation, aspiration & esophageal intubation (Less use of GA). Incidence of difficult intubation has remained the same. Whereas, claims for maternal nerve injury and back pain has increased substantially. 21% 21% Fitzgibbon et al. Anesthesiology 112:948-56, Davies et al. Anesthesiology 110:131-9, Obstetric Anesthesia: Most claims (71%) for newborn death/brain damage were associated with non-reassuring FHR tracing and with urgent/emergent C/S. Anesthesia was judged to have contributed in only 22% of cases (anesthesia delay, poor communication with OB, substandard care). Maternal nerve injury, 80% were temporary/non-disabling. Associated with regional anesthesia and, more commonly, vaginal delivery. Radiculopathy of a lumbar or sacral root were the most common injuries. Does not account for nerve injury from obstetric causes. Davies et al. Anesthesiology 110:131-9, Pediatric Anesthesia: Claims for death (41%) and brain damage (21%) from , despite decreasing, remain the most common causes of pediatric anesthesia injuries. Cardiovascular (26%) and respiratory (23%) events were the most common damaging events. 79% of claims involved patients with ASA I-II. Common surgical procedures involved the airway (33%) such as dental, ears, nose, throat and maxillofacial procedures. Jimenez et al. Anesth Analg 104:147-53,

9 Pediatric Perioperative Cardiac Arrest Registry: : Formed in 1994 to study the causes and outcomes from perioperative cardiac arrests in anesthetized children (Voluntary Participation of 80 North American Institutions). From , 49% (N = 193) of cardiac arrest reported were related to anesthesia. Cardiovascular (41% of arrests) were the most common inciting event: 1) hypovolemia from blood loss and 2) hyperkalemia from transfusion of stored blood. Respiratory causes (27% of arrests): laryngospasm remain the most common inciting event. Medication related arrests accounted for 18% (i.e. halothane and cardiac depression). From , represented the most common cause. Jimenez et al. Anesth Analg 104:147-53, Bhananket et al. Anesth Analg 105:344-50, Conclusions: ASA Closed Claims Database is a very useful tool to study infrequent complications in anesthesia care, esp. the raise of trends such as injury from peripheral nerve blocks or brain damage/spinal cord injury during procedures in the beach chair position. Hospitals and Departments can institute standard operating procedures to prevent rare complications (i.e. use of ultrasound for nerve blocks). However, regardless of the number of claims, no causality can be drawn from patient demographics, surgery and postoperative care due to the inherent limitation of the database. More research (clinical and basic) is needed to understand the mechanisms underlying common anesthetic complications. 9