Preoperative anterior thigh temperature does not correlate with perioperative temporal hypothermia during cesarean delivery with spinal anesthesia: Secondary analysis of a randomized control trial

Association between preoperative toe perfusion index and maternal core temperature decrease during cesarean delivery under spinal anesthesia: a prospective cohort study

Background

The main mechanism of body temperature decrease during cesarean delivery under spinal anesthesia is core-to-peripheral redistribution of body heat, attributable to vasodilation. Perfusion index (PI) obtained with a pulse oximeter helps to assess peripheral perfusion dynamics by detecting the change in peripheral vascular tone. This study aimed to examine whether preoperative toe PI could predict the decrease in core temperature induced by spinal anesthesia during cesarean delivery.

Methods

Parturients undergoing scheduled cesarean delivery under combined spinal-epidural anesthesia from September 2019 to March 2020 were enrolled in this single-center prospective cohort study. All parturients received 0.5% hyperbaric bupivacaine (10 mg) with fentanyl (15 μg) intrathecally. A pulse oximeter probe was placed on the left second toe for continuous PI measurement. The 3 M™ Bair Hugger™ Temperature Monitoring System placed over the right temporal region was used to record core temperature over time. We evaluated the association between the maximum core temperature decrease, which is the primary outcome, and the preoperative toe PI at operating room (OR) admission using a segmented regression model (SRM) and a generalized additive model (GAM). The maximum core temperature decrease was defined as the difference between core temperature at OR admission and minimum intraoperative core temperature.

Results

Forty-eight patients were evaluated. In the SRM, the slope for the association between the maximum core temperature decrease and the preoperative toe PI changed from 0.031 to 0.124 after PI = 2.4%. Likewise, with the GAM, there was a small core temperature decrease when preoperative toe PI was greater than 2.0 to 3.0%.

Conclusions

Low preoperative toe PI was associated with maternal core temperature decrease during cesarean delivery under spinal anesthesia. Preoperative toe PI is a simple, non-invasive, and effective tool for the early prediction of perioperative core temperature decrease during cesarean delivery.

Trial registration

UMIN Clinical Trials Registry (registry number: UMIN000037965).

Effect of Preoperative Oral Carbohydrate Loading on Body Temperature During Combined Spinal-Epidural Anesthesia for Elective Cesarean Delivery

BACKGROUND

Intraoperative hypothermia is a common complication after neuraxial block in cesarean delivery. At least 1 animal study has found that carbohydrate loading can maintain the body temperature of rats during general anesthesia, but it is unclear whether carbohydrate loading is beneficial for body temperature maintenance in parturient women during combined spinal-epidural anesthesia (CSEA) for elective cesarean delivery.

METHODS

Women undergoing elective cesarean delivery were randomized into a control group (group C), an oral carbohydrate group (group OC), or an oral placebo group (group OP), with 40 women in each group. Core body temperature (Tc) and body surface temperature (Ts) before and after cesarean delivery, changes in Tc (ΔTc) and Ts (ΔTs), and the incidence of side effects (eg, intraoperative shivering) were compared among the groups.

RESULTS

The postoperative Tc (core body temperature after cesarean delivery [Tc2]) of group OC (36.48 [0.48]°C) was higher than those of group C (35.95 [0.55]°C; P < .001), and group OP (36.03 [0.49]°C; P = .001). The ΔTc (0.30 [0.39]°C) in group OC was significantly smaller than those in group C (0.73 [0.40]°C; P = .001) and group OP (0.63 [0.46]°C; P = .0048).

CONCLUSIONS

Oral carbohydrate loading 2 hours before surgery facilitated body temperature maintenance during CSEA for elective cesarean delivery.