Effectiveness of Combined Strategies for the Prevention of Hypothermia Measured by Noninvasive Zero-Heat Flux Thermometer During Cesarean Section

Abstract

Background: Perioperative hypothermia (body temperature <36°C) is a common complication of anesthesia increasing the risk for maternal cardiovascular events and coagulative disorders, and can also influence neonatal health. The aim of our work was to evaluate the impact of combined warming strategies on maternal core temperature, measured with the SpotOn. We hypothesized that combined modalities of active warming prevent hypothermia in pregnant women undergoing cesarean delivery with spinal anesthesia. Methods: Seventy-eight pregnant women were randomly allocated into three study groups receiving warmed IV fluids and forced-air warming (AW), warmed IV fluids (WF), or no warming (NW). Noninvasive core temperature device (SpotOn) measured maternal core temperature intraoperatively and for 30 min after surgery. Maternal mean arterial pressure, incidence of shivering, thermal comfort and newborn's APGAR, axillary temperature, weight, and blood gas analysis were also recorded. Results: Incidence of hypothermia was of 0% in AW, 4% in WF, and 47% in NW. Core temperature in AW was constantly higher than WF and NW groups. Incidence of shivering in perioperative time was significantly lower in AW and WF groups compared with the NW group (p < 0.04). Thermal comfort was higher in both AW and WF groups compared with NW group (p = 0.02 and p = 0.008, respectively). There were no significant differences among groups for the other evaluated parameters. Conclusion: Combined modalities of active warming are effective in preventing perioperative hypothermia. The routine uses of combined AW are suggested in the setting of cesarean delivery.

Keywords: SpotOn; cesarean delivery (CD); core temperature; perioperative hypothermia; spinal anesthesia.

Figure 1

Flowchart of patient's enrolment.

Figure 2

Core temperature (CT°) variation during the perioperative time. Data are expressed in terms of mean ± standard deviation. NW, IV fluids at room temperature and no forced-air warming; WF, warmed IV fluids; AW, warmed IV fluids and forced-air warming; P, p-value; CT°, core temperature, expressed in °C; T°OR, temperature in the operating room, expressed in °C; CT°, core temperature; T5, T15, T25, T35, T45, and T55: 5, 15, 25, 35, 45, and −55 min from baseline, respectively. £, AW vs. WF (p = 0.023); *, AW vs. NW (p = 0.001); #, AW vs WF (p = 0.025); §, AW vs NW (p < 0.001); °, WF vs NW (p = 0.047); +, AW vs NW (p < 0.001); ç, WF vs NW (p = 0.004); ò, AW vs. NW (p < 0.001); &, AW vs. WF (p = 0.001).

Figure 3

Thermal comfort score evaluation (TCS) during the perioperative time. Thermal comfort score evaluation. Data are expressed in terms of mean ± standard deviation. TCS, thermal comfort score (mm); NW, IV fluids at room temperature and no forced-air warming; WF, warmed IV fluids; AW, warmed IV fluids and forced-air warming; T20, at 20 min from baseline; T40, at 40 min from baseline. *, NW vs. WF (p = 0.04); #, NW vs. AW (p = 0.007); +, NW vs. WF (p < 0.001); §, NW vs. AW (p = 0.02); ç, NW vs. WF (p = 0.008).