Norepinephrine With Ephedrine Versus Norepinephrine Alone During Spinal Anesthesia for Cesarean Delivery

We hypothesize that the addition of ephedrine to norepinephrine infusion could decrease the incidence of post spinal hypotension(PSH) in parturient undergoing C.S under spinal anesthesia and minimize the changes in heart rate

Aim of the work: To compare between concomitant use of norepinephrine infusion with ephedrine versus use of norepinephrine infusion alone on maternal B.P following induction of spinal anaesthesia for C.S delivery. Statistical analysis Sample Size: Our primary outcome is the incidence of post-spinal hypotension. In a previous study incidence of post spinal hypotension in the noradrenaline group was 32%. We calculated a sample size that could detect at least 50% difference between study groups. Using MedCalc Software version 14 (MedCalc Software bvba, Ostend, Belgium), a sample size of 246 patients will be needed to have a study power of 80% and alpha error of 0.05. The number was increased to be 260 envelopes (130 envelopes per group) to compensate for possible dropouts. Statistical analysis: Analysis of data will be performed using Statistical package for social science (SPSS) software, version 26 for Microsoft Windows (SPSS Inc., Chicago, iL, USA). Categorical data will be reported as frequency and percentages and will be analyzed using chi-squared test. Continuous data will be checked for normality using Kolmogorov-Smirnov test. Normally distributed data will be presented as means ±standard deviations and will be analyzed using unpaired student t-test. Skewed data will be expressed as medians(quartiles) and will be analyzed using Mann Whitney U test. A two-way repeated measures ANOVA will be used to evaluate dose (between-groups factor) and time (repeated measures)". P value of 0.05 or less will be considered significant.