Intravenous anesthetics' impact on human uterine contractility to be compared in vitro, informing postpartum hemorrhage prevention

Poor uterine tone, or uterine atony, is the leading cause of postpartum hemorrhage (PPH), a major contributor to maternal mortality worldwide. While general anesthesia has been linked to increased blood loss compared to regional anesthesia during cesarean sections, the specific impact of intravenous anesthetic agents on uterine contractility remains largely understudied in human tissue. Current evidence from rat models suggests high doses of these drugs might reduce uterine tone, whereas low-dose ketamine could increase it. Understanding these effects is crucial, as oxytocin is the primary uterotonic drug used to prevent and treat PPH, and anesthetic choices could modulate its efficacy.

This in-vitro study will compare three intravenous anesthetic induction agents on human myometrial tissue strips under physiological laboratory conditions. Myometrial strips will be obtained and maintained in organ baths. Following a 2-hour equilibration, the strips will be washed and exposed to physiological saline solution (PSS) for 30 minutes. The primary endpoints are the agents' impact on spontaneous uterine contractility and contractility induced by 10-7 M oxytocin for 10 minutes, followed by continuous oxytocin exposure for 60 minutes. This will be the first study to directly compare these specific drugs on human uterine tissue, aiming to determine their dose-dependent effects.