Treatment of and outcomes from hypotension in the post-anaesthesia care unit: A single-centre retrospective cohort study.

Abstract

Hypotension after non-cardiac surgery is common and associated with harm. Anaesthetists treat hypotension in the post-anaesthesia care unit (PACU) with intravenous (IV) fluids and vasopressor medications. Our aim was to determine the incidence of hypotension after these treatments. We conducted a single centre retrospective cohort study of all adult patients who were hypotensive (systolic blood pressure less than 90 mmHg) in the PACU after non-cardiac, non-obstetric surgery over a one-year period. The primary outcome was a composite of hypotension or vasopressor infusion in the 24 h after PACU discharge. During the study 459 patients were hypotensive in the PACU. No treatment was administered in 232 (51%) episodes, IV fluid alone was administered in 138 (30%) episodes, vasopressors alone were administered in 22 (5%) episodes, and both fluid and vasopressors were administered in 67 (14%) patients. A total of 167 patients (36%) met the primary outcome, of which 118 (25%) were hypotensive and 49 (11%) required vasopressor infusions. The treatment group was significantly associated with the primary outcome (P < 0.001), with 36 (15%) patients who received no treatment becoming hypotensive, compared with 67 (46%, P < 0.001) patients who received IV fluid alone, 12 (55%, P < 0.001) who received vasopressors alone and 52 (75%, P < 0.001) who received both IV fluid and vasopressors. Patients who were hypotensive in the PACU frequently developed later hypotension or required vasopressors in the 24 h after PACU discharge. Treatments delivered in the PACU had limited long-term effectiveness. Novel treatments to protect patients from subsequent hypotension are urgently needed.