Acute complications in the post-anaesthesia care unit after infrainguinal surgery for lower limb ischaemia - a prospective observational cohort study.

Background: Arterial surgery for lower limb ischaemia is a frequently performed procedure in patients with severe cardio-pulmonary comorbidities, making them high-risk patients for acute postoperative complications with a need for prolonged stay in the post-anaesthesia care unit (PACU). However, detailed information on complications during the PACU stay is limited, hindering mechanism-based interventions for early enhanced recovery. Thus, we aimed to systematically describe acute complications and related risk factors in the immediate postoperative phase after infrainguinal arterial surgery. Patients and methods: Patients transferred to the PACU after infrainguinal arterial surgery due to chronic or acute lower limb ischaemia were consecutively included in a six-month observational cohort study. Pre- and intraoperative data included comorbidities as well as surgical and anaesthetic technique. Data on complications and treatments in the PACU were collected every 15 minutes using a standardised assessment tool. The primary endpoint was occurrence of predefined moderate or severe complications occurring during PACU stay. Results: In total, 155 patients were included for analysis. Eighty (52%) patients experienced episodes with oxygen desaturation (<85%) and moderate or severe pain occurred in 72 patients (47 %); however, circulatory complications (hypotension, tachycardia) were rare. Preoperative opioid use was a significant risk factor for moderate or severe pain in PACU (59 vs. 38% chronic vs. opioid naive patients (P = 0.01). Conclusions: Complications in the PACU after infrainguinal arterial surgery relates to saturation and pain, suggesting that future efforts should focus on anaesthesia and analgesic techniques including opioid sparing regimes to enhance early postoperative recovery.