Effects Of Different Vasopressor On Maternal And Fetus During Spinal Anesthesia For Emergency Cesarean Delivery

Objective: After combined spinal-epidural anesthesia,the cesarean section of the maternal hypotension is an important theme of obstetric anesthesia.Most of the studies focused on the elective cesarean section,however,our studies are to compare the different treatments of vasopressors for the emergency caesarean section maternal hypotension and influences on maternal and fetus.Methods: The maternal are chosen from Yan'an University Affiliated Hospital,who are to receive emergency caesarean section,ASA?-?,from July 2016 to December 2016.And they are divided into 3 groups randomly :Ephedrine Group(E),Phenylephrine Group(P)and Norepinephrine Group(NE).On arrival at the operating room,standard noninivasive monitoring is applied.Blood pressure is measured every 3 minutes,baseline systolic blood pressure and heart rate are calculated as the three successive measurements of systolic blood pressure.Blood pressure is measured at 1min interval after spinal injection.When the systolic blood pressure is lower than 80% of the baseline blood pressure or the absolute value of the systolic blood pressure is less than 100 mm Hg,the groups are given ephedrine 1 ml(8 mg / ml)?phenylephrine 1ml(100?g / ml)and norepinephrine 1ml(5?g / ml).The result of the interval measurement for blood pressure is still hypotension,vasopressors are given continuously until the blood pressure returns to normal range.The period from onset of hypotension until its correction is considered as one hypotension episode.Intravenous atropine 0.5mg is administered if a HR < 60 beats/min is associated with hypotension,or the HR is < 50 beats/min irrespective of SBP.The duration of each blood pressure and heart rate measurement,the times of medication,the duration of hypotension,the fetal umbilical cord blood parameters and the Apgar score are recorded from the spinal injection to the fetus delivery.Result: 1.The general situation of the three groups of the maternal and the differences from the spinal anesthesia injection to the fetus are not statistically significant(P>0.05).2.Comparison of results of the three groups,the incidence of PH,PO2,PCO2,BE,lac,fetal acidosis and Apgar score are similar in umbilical cord blood,the differences are not statistically significant(P>0.05).3.Baseline heart rate,baseline blood pressure,the longest duration of hypotension,the highest and the lowest blood pressure during the study period are not statistically significant(P > 0.05).The number of episodes of hypotension,the total times of hypotension,the highest systolic blood pressure after treatment and the lowest heart rate during the study period are comparable,the differences are statistically significant(P <0.05)The number of maternal hypotension episodes?the total times of hypotension and The highest systolic blood pressure after treatment and the differences between Group E and Group NE are statistically significant(P = 0.019,P = 0.004,P = 0.007).There are no significant differences between Group E and Group P(P> 0.05).There are no significant differences between Group P and Group NE(P> 0.05).Comparison of the lowest heart rate during the study period,the differences between Group E and Group P are significant(P=0.04),the differences between Group P and Group NE are statistically significant(P=0.022),there are no significant differences between Group E and Group NE.4.The HR and SDP trends after spinal injection are compared after the first 10 minutes.The blood pressures of the three groups at 8th minute(ie,about two minutes after treatment)are significantly different from the statistical significance(P = 0.033).Blood pressures are significantly different between Group E and Group NE(P = 0.009).At 8th,9th,10 th min,the differences of the heart rate in the three groups were statistically significant(P = 0.035 P = 0.005 P = 0.013).HR: There are significant differences between Group E and Group P,the differences between Group P and Group NE are statistically significant,there are no significant differences between Group E and Group NE.5.Comparison of the maternal adverse reactions among the three groups.nausea and vomiting and reflex hypertension are similar,the differences are not statistically significant,bradycardia is statistically significant(P <0.05).Conclusion:Ephedrine,Phenylephrine and Norepinephrine can be used safely and effectively for emergency cesarean section of the maternal hypotension treatment.However,the use of high doses of ephedrine still need to be cautious,it may cause fetal PH reduction and fetal acidosis.Phenylephrine may be a better choice for mothers with tachycardia.Norepinephrine may become the main of vasopressors obstetric anesthesia,but the optimal dose and the use of the program also need to be studied further.