A systematic review of risk factors for postinduction hypotension in surgical patients undergoing general anesthesia

Clinical evidence has proved that postinduction hypotension (PIH) is very prevalent in surgical patients undergoing general anesthesia, and commonly develops within 20 min after the induction of general anesthesia. However, the risk factors for PIH are not clear till now, therefore, a systematic review of current evidence was conducted.

PubMed, Embase, Cochrane library, and Web of Science were searched for articles published in English up to June 2021. The following search items were used: postinduction, postintubation, propofol induction, anesthesia induction, general anesthesia induction, hypotension, risk factor, general anesthesia, surgery. The articles were screened using the inclusion and exclusion criteria, and the data from included studies were extracted and analyzed.

Twelve studies were included. Seven studies reported the association between age and PIH, and six showed age was a risk factor. Five or three studies reported the association between mean arterial pressure (MAP) and PIH or between systolic blood pressure (SBP) and PIH, but the results were conflicting. Results from two studies regarding gender and PIH were conflicting. Two studies reported that weight was negatively correlated with PIH. Low baseline blood volume, emergency operation, long-term intake of the angiotensin converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) were risk factors for PIH. One study showed that ASA III-V, propofol induction, and increasing fentanyl dosage were risk factors for PIH.

Aging, ASA III-V, emergency operation, low baseline blood volume, long-term intake of ACEI/ARB, propofol induction, and increasing fentanyl dosage are potential risk factors for PIH, while body weight gain is a protective factor. Based on the current evidence, it is difficult to determine whether baseline blood pressure or gender is associated with the development of PIH.