The Effect Of Phenylephrin Prevention Hypotension By Combine Spinal-Epidura Anesthesia For Gynaecology

Objiective: To study the effect of phenylephrine on hypotension and hemodynamics during combined spinal-epidural anesthesia for gynaecology.Methods: Sixty ASAI～II patients scheduled for gynaecology under combined spinal-epidural anesthesia were divided into there experimental groups: phenylephrine 100μg( group P),ephedrine 8mg ( group E) and Ringer's solution(group R) .Each group inovolves 20 patients . The epidural space was identified at the L3-4 interspace.The speed of infusion to cavitas subarachnoidealis in all patients was 0.2ml/s. epidural catheter was inserted 3.5 cm into the epidural space and secured with tap.All patients had an intravenous catheter inserted in a peripheral arm vein and Ringer's solution was administered 10m/kg before anesthesia.Epidural administration of anesthesia according to the decision . HR,BP,Sp02 and ECG were continuously monitored when patients entering the room.Phenylephrine was put on a drip in 100μg before spinal anesthesia in P group. Ephedrine was put on a drip in 5mg before spinal anesthesia in E group.R group were injected lactated Ringers solution at the rate of 25ml/min, 15ml/ kg. The foundation values of SBP,DBP,HR after patients entering room (T₀),after pretreatment (T₁) were recorded .The change of BP and HR of 5min (T2),10min (T3),15min (T4 ) were observed and recorded after intrathecal local anesthetic administration. The value and the occurring time of the lowest blood pressure and heart rate during surgering,the incidenc and the numbers of hypotension, bradycardia, respiratory depression, shivering, nausea and vomit, postdural puncture headache (PDPH)etc, they are recorded .Rsults: It doest exist significant differences among three groups of the time of SBP, DBP, HR when entering the operating room. the difference was not statistically significant (P>0.05). SBP, DBP, HR of three groups of patients within 60min were decreased, P group of patients in T2, T3 and T4 time point T0, compared with BP, HR no significant change (P>0.05). Group E patients in T2, T3 and T4 time point and at the same time point T0, and P compared with BP, HR no significant change (P>0.05),no statistically significant difference (P>0.05). R patients T2, T3 and T4 time points T0 and at the same point in the BP and HR compared with A group changed significantly (P<0.05). Three sets of BP and HR significantly different trends, the gap was statistically significant (P<0.05). P, E, Rgroup after anesthesia were 1, 2, 2cases of hypotension, ephedrine 10mg were given after the correction, the two groups was statistically different (P<0.05). All patients had no significant respiratory depression, nausea, vomiting and headache after surgery.Conclusion: Low dose of phenylephrine pretreatment significantly reduced incidence of hypotension except of patients with severe heart and lung disease before anesthesia.