Title: A Prophylactic Phenylephrine Infusion for Preventing Hypotension during Spinal Anaesthesia for Caesarean Section and to Study its Effects on APGAR Score and Umbilical Artery Blood pH

Authors: Bilal Mohammad, Pavan Dhulkhed, P.B. Jamale, Tushar Munnoli, V.K. Dhulkhed

 DOI:  https://dx.doi.org/10.18535/jmscr/v4i12.34

Abstract

BACKGROUND: Hypotension after spinal anaesthesia for caesarean section is a common complication. The usual approach to use vasopressors in this clinical setting is reactive rather than proactive; spinal anaesthesia induced hypotension is allowed to develop and then treated accordingly. We have, insteadstudied prophylactic phenylephrine infusion for prevention of hypotension and its effects on APGAR score and umbilical artery blood pH.

METHOD: Nonlaboring patients scheduled for elective cesarean sections were randomly allocated into two groups of 30 each. Group I received intravenous prophylactic phenylephrine infusion at 100 mcg minute-1for 3minutesafter spinal anaesthesia. Then each minute systolic arterial pressure(SAP) was measured and infusion stopped if SAP> 20% baseline and continued or restarted, otherwise. Intravenous phenylephrine bolus100 mcg was given when SAP is decreased to <20% of baseline. Group II received ephedrine 6 mg bolus only when SAP decreased to <20% of base line. After1minute of spinal anaesthesia; Heart rate (HR), SAP were recorded every minute till the extraction of the baby. After the delivery of the baby, APGAR score at 1 and 5 minutes were noted. Umbilical artery blood pHwas analysed.

RESULTS: Prophylactic phenylephrine infusion decreased the incidence (2of 30 [6.66%] versus 29 of 30[96.66%]) of hypotension compared with control. Heart rate was significantly lower in the infusion group. Umbilical artery blood pH and APGAR scores were similar.

CONCLUSION: Prophylactic phenylephrine infusion is an effective and simple method of reducing the incidence of hypotension during spinal anaesthesia for cesarean delivery, with no adverse effect on neonatal outcome.

KEYWORDS: Prophylactic Phenylephrineinfusion, Spinalanaesthesia,Maternal hypotension, Cesarean section.

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Corresponding Author

Dr Bilal Mohammad

Post Graduate Student, Department of Anaesthesiology,

Krishna Institute of Medical Sciences, Karad, Maharashtra, India

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