Impact of interval between induction of spinal anesthesia to delivery on umbilical arterial cord ph of neonates delivered by elective cesarean section

Abstract

Background To evaluate the impact of interval between induction of spinal anesthesia to delivery of the fetus by elective cesarean section on umbilical arterial pH and neonatal outcome. Patients and methods Two hundred and twenty pregnant women who were planned for elective cesarean section at term under spinal anesthesia were recruited. Minimum systolic, diastolic and mean arterial blood pressures (SBP, DBP, MAP) and largest pressure decrease (SBP, DBP, MPA) were also recorded. Induction of spinal anesthesia to delivery interval was measured. Following delivery, umbilical arterial cord analysis for pH and base deficit were done. Apgar scores at 1 min and at 5 min, neonatal intensive care unit (NICU) admission, need for mechanical ventilation and incidence of hypoxemic-ischemic encephalopathy were recorded. Results Induction of spinal anesthesia to delivery interval was 25.7 ± 5.6 min. Lowest SBP and MAP reached during cesarean delivery were 88.9 ± 7.3 mmHg and 60.4 ± 5.6 mmHg, respectively. MAP < 65 mmHg was reached in 136 (62%) patients with a decrease of MAP of > 20% in 149 (68%) patients. Duration of the longest hypotension episode was 3.3 ± 2.2 min. All patients required ephedrine administration for hypotensive episodes with an average dosage of 11.4 ± 3.2 mg. Umbilical pH of 7.3 ± 0.1 and base deficit of 8.3 ± 4.4 mmol/l were recorded. Apgar scores at 5 min were 8.5 ± 1.2. Eight (3.6%) neonates were admitted in the NICU. One neonate needed mechanical ventilation. There were no cases of hypoxemic-ischemic encephalopathy. There were inverse correlations between induction of spinal anesthesia to delivery interval, body mass index (BMI) and duration of longest hypotension episode in relation to umbilical pH (r = -0.817, -0.395 and -0.268, respectively). Cut off value for induction of spinal anesthesia to delivery interval greater than 27 min predicted an umbilical pH of < 7.2. Cut off value for the duration of the longest hypotension episode greater than 5 min predicted an umbilical pH of < 7.2. Cut off value for BMI greater than 35 kg/m2 predicted an umbilical pH of < 7.2. Conclusion Prolonged interval between induction of spinal anesthesia to delivery could be associated with neonatal acidosis. This could be aggravated by maternal obesity and prolonged duration of hypotension episodes during cesarean delivery.

Exploring factors influencing skin incision to the delivery time and their impact on neonatal outcomes among emergency cesarean deliveries indicated for non-reassured fetal heart rate status

“…Unsurprisingly, numerous studies showed a significant association between longer S-D intervals and more detrimental newborn outcomes, consistent with our findings ( 4 – 19 ). However, some factors influencing S-D time have no impact on neonatal outcomes.…”

The Association of Fetal Acidemia With Adverse Neonatal Outcomes at Time of Scheduled Cesarean Delivery

“…Other risk factors identified for fetal acidemia were longer times between neuraxial placement to delivery and skin incision to delivery. These align with previous literature 3,4 and highlight the importance of effective coordination of the care team to minimize pre-delivery time following anesthetic administration. Hysterotomy to delivery time is a similar risk factor that was not explicitly analyzed in this study but has been identified in previous literature.…”

Spinal Hypotension and Time from Spinal-to-Delivery in Scheduled Cesarean Deliveries: Association with Neonatal Acidosis

“…5 Similarly, Hassanin et al 13 reported that 100% of their patients received predelivery vasopressors, but notably, prophylactic administration was not standard of care, and more than two-thirds (67.7%) of their patients had a recorded MAP that was >20% drop from baseline after spinal administration. 13 In all these studies, the authors reported that prophylactic vasopressors may have been used at the discretion of the anesthesiologist but that the practice was not considered routine. In addition, several prior studies found time from spinalto-delivery to be independently associated with neonatal acidosis.…”

“…Finally, we have provided data on CMAO, which prior publications did not. 2,4,5,13 We acknowledge several limitations to our study. This was a single-center study which may decrease generalizability.…”