American Society of Anesthesiologists physical status classification predicts perianesthetic morbidity and mortality of companion pigs

Objective: To determine and describe the morbidity and mortality following the procedural sedation and general anesthesia of pigs at a tertiary university large animal referral hospital. Methods: Medical records of all pigs undergoing procedural sedation or general anesthesia from January 2019 until December 2023 were reviewed in this single-center, cohort, observational analysis. Information regarding patient demographics, sedation/anesthetic protocol, recovery from sedation/anesthesia, and perianesthetic complications was analyzed for each anesthetic event. Logistic regression analysis was used to examine the variables associated with morbidity and mortality. Results: 447 procedural sedation or general anesthetic events for 304 pigs were analyzed. Intraprocedural anesthetic complications were observed in 117 of 214 procedural sedation events (54.7%) and 185 of 233 general anesthesia events (79.4%). The most frequent intraprocedural complication was low peripheral oxygen saturation (177 of 438 [40.4%]). There were increased intraprocedural anesthetic complications in pigs with an American Society of Anesthesiologists (ASA) status of III-IV when compared to an ASA status of I or II (OR, 3.236; 95% CI, 1.52 to 6.81). Death due to a perianesthetic complication was observed following 7 of 447 events (1.6%). An ASA status of III-IV was associated with increased mortality within 48 hours (OR, 25.40; 95% CI, 7.25 to 89.93). Conclusions: Porcine perianesthetic morbidity and mortality were associated with ASA physical status classification. Clinical Relevance: Thorough preanesthetic assessment for porcine patients is imperative. Pulse oximetry and oxygen supplementation should be utilized during the perianesthetic period.