Perioperative hypotension and discharge outcomes in non-critically injured trauma patients, a single centre retrospective cohort study

Background: There is a lack of information on the effect of age on perioperative care and outcomes after minor trauma in the elderly. We examined the association between perioperative hypotension and discharge outcome among non-critically injured adult patients. Methods: We conducted a retrospective study of non-critically ill patients (ISS <9 or discharged within less than 24 h) who received anaesthesia care for surgery and Recovery Room care at a level-1 trauma centre between 5/1/2012 and 11/30/2013. Perioperative hypotension was defined as systolic blood pressure (SBP) <90 mmHg (traditional measure) for all patients, and SBP <110 mmHg (strict measure) for patients >= 65 years. Poor outcome was defined as death or discharge to skilled nursing facility/hospice. Results: 1744 patients with mean ISS 4.4 across age groups were included; 169 (10%) were >= 65 years. Among patients >= 65 years, intraoperative hypotension occurred in >75% (131/169, traditional measure) and in > 95% (162/169, strict measure); recovery room hypotension occurred in 2% (4/169) and 29% (49/169), respectively. Mean age-adjusted anaesthetic agent concentration (MAC) was similar across age groups. Opioid use decreased from 9.3 (SD 5.7) mg/h morphine equivalents in patients <55 years to 6.2 (SD 4.0) mg/h in patients over 85 years. Adjusted for gender, ASA score, anaesthesia duration, morphine equivalent/hr, fluid balance, MAC and surgery type, and using traditional definition, older patients were more likely than patients <55 to experience perioperative hypotension: aRR 1.21, 95% CI 1.11-1.30 for 5564 and aRR 1.19, 95% CI 1.07-1.32 for ages 65-74. Perioperative hypotension was associated with poor discharge outcome (aRR 1.55; 95% CI 1.04-2.31 and aRR 1.87; 95% CI 1.17-2.98, respectively). Conclusion: Despite age related reduction in doses of volatile anaesthetic and opioids administered during anaesthesia care, and regardless of hypotension definition used, non-critically injured patients undergoing surgery experience a large perioperative hypotension burden. This burden is higher for patients 55-74 years and older and is a risk factor for poor discharge outcomes, independent of age and ASA status. (C) 2017 Elsevier Ltd. All rights reserved.