Anesthesia and poliomyelitis: A matched cohort study

BACKGROUND: Poliomyelitis is a viral infectious disease caused by 1 of the 3 strains of poliovirus. The World Health Organization launched an eradication campaign in 1988. Although the number of cases of poliomyelitis has drastically declined, eradication has not yet been achieved, and there are a substantial number of survivors of the disease. Survivors of poliomyelitis present a unique set of challenges to the anesthesiologist. The scientific literature regarding the anesthetic management of survivors of poliomyelitis, however, is limited and primarily experiential in nature. Using a retrospective, matched cohort study, we sought to more precisely characterize the anesthetic implications of poliomyelitis and to determine what risks, if any, may be present for patients with a history of the disease. METHODS: Using the Mayo Clinic Life Sciences System Data Discovery and Query Builder, study subjects were identified as those with a history of paralytic poliomyelitis who had undergone major surgery at Mayo Clinic Rochester between 2005 and 2009. For each case, 2 sex- and age-matched controls that underwent the same surgical procedure during the study period were randomly selected from a pool of possible controls. Medical records were manually interrogated with respect to demographic variables, comorbid conditions, operative and anesthetic course, and postoperative course. RESULTS: We analyzed 100 cases with 2:1 matched controls and found that the peri- and postoperative courses were very similar for both groups of patients. Pain scores, postanesthesia care unit admission, length of postanesthesia care unit stay, intensive care unit admission, length of intensive care unit stay, and initial extubation location were not significantly different between the 2 groups. Looking at pulmonary complications in our primary outcome, there was no significant difference between the 2 groups (17% vs 14% for polio versus control, respectively; conditional logistic regression odds ratio = 1.5; 95% confidence interval, 0.7-3.3; P = 0.33). In addition, no difference was noted in those requiring a code or rapid response team intervention (4% vs 3% for polio versus control; P = 0.46) and the 30-day mortality rate was also not significantly different, with 2% of polio patients dying compared with 3% of controls (P = 0.79). The analysis of the primary outcome was repeated for the subset of patients with a history of poliomyelitis who had persistent neurologic deficits preoperatively (n = 36) and their matched controls (n = 72). In this subset analysis, there were 4 (11%) polio patients and 8 (11%) control patients who experienced pulmonary complications (conditional logistic regression odds ratio = 1.00; 95% confidence interval, 0.27-3.72; P = 1.00). The percentage of patients experiencing specific pulmonary complications of interest was similar between groups (postoperative mechanical ventilation: 6% vs 8% for polio and control patients, respectively; prolonged mechanical ventilation: 0% vs 1%; reintubation: 8% vs 4%; pulmonary infection: 6% vs 6%; and aspiration: 0% vs 1%). CONCLUSIONS: This study suggests that patients with a history of poliomyelitis do not seem to have an increased risk of pulmonary complications in the perioperative period. However, an odds ratio as great as 3.3-fold may be present.