Respiratory Depression Following Cesarean Delivery With Single-Shot Spinal With 100 μg Morphine

Abstract

Purpose: We aimed to evaluate the rate of cumulative bradypnea time (total bradypnea time/total monitoring time) and its related factors in these parturients.Methods: This was a prospective observational study of women undergoing elective and non-elective cesarean delivery under single-shot spinal including 0.1 mg morphine. The Berlin Questionnaire was used to screen for sleep apnea syndrome preoperatively. Respiratory rate and oxygen saturation (SpO2) were monitored continuously using an adhesive acoustic respiration sensor and pulse oximeter, respectively, at least 6 hours after cesarean delivery. Bradypnea was defined as a respiratory rate < 8 bpm lasting at least 25 s (sustained bradypnea) and at least 15 s (immediate bradypnea), respectively. Hypoxemia was defined as SpO2 < 92% lasting at least 25 s (sustained hypoxemia) and at least 15 s (immediate hypoxemia) multiple regression analysis was applied to assess related factors to the rate of cumulative sustained bradypnea.Results: Of 159 patients with a mean body mass index of 26.0 kg/m2, the Berlin Questionnaire was positive in 16.3%, and 77 (48.4%) experienced sustained bradypnea. The median rate of cumulative sustained bradypnea time was 0.70 % (interquartile range 0.35 to 1.45) without any related factors. The incidence of immediate bradypnea and sustained and immediate hypoxemia were 58.5%, 24.5%, and 37.7%, respectively. However, none of the factors were statistically significant. Conclusion: After cesarean delivery performed with intrathecal morphine 0.1 mg, respiratory depression events were commonly observed. However, the rate of cumulative bradypnea time was very low and there were no related factors.Trial registration number and date of registration: UMIN Clinical Trials Registry (UMIN 0035832) and Dec. 24th, 2018