Occurrence of Symptomatic Hypotension in Patients Undergoing Breast Free Flaps: Is Enhanced Recovery after Surgery to Blame?

Background: Enhanced recovery after surgery (ERAS) initiatives improve postoperative function and expedite recovery, leading to a decrease in length of stay. The authors noted a high rate of postoperative symptomatic hypotension in patients undergoing abdominal free flap breast reconstruction and wished to explore this observation. Methods: Subjects undergoing abdominal free flap breast reconstruction at the authors' institution from 2013 to 2017 were identified. The ERAS protocol was initiated in 2015 at the authors' hospital; thus, 99 patients underwent traditional management and 138 patients underwent ERAS management. Demographics and perioperative data were collected and analyzed. Postoperative symptomatic hypotension was defined as mean arterial pressure below 80 percent of baseline with symptoms requiring evaluation. Results: A significantly higher rate of postoperative symptomatic hypotension was observed in the ERAS cohort compared with the traditional management cohort (4 percent versus 22 percent; p < 0.0001). Patients in the ERAS cohort received significantly less intraoperative intravenous fluid (4467 ml versus 3505 ml; p < 0.0001) and had a significantly increased amount of intraoperative time spent with low blood pressure (22 percent versus 32 percent; p =0.002). Postoperatively, the ERAS cohort had significantly lower heart rate (77 beats per minute versus 88 beats per minute; p < 0.0001) and mean arterial pressure (71 mmHg versus 78 mmHg; p < 0.0001), with no difference in urine output or adverse events. Conclusions: The authors report that ERAS implementation in abdominal free flap breast reconstruction may result in a unique physiologic state with low mean arterial pressure, low heart rate, and normal urine output, resulting in postoperative symptomatic hypotension. Awareness of this early postoperative finding can help better direct fluid resuscitation and prevent episodes of symptomatic hypotension.