ABSTRACT
Objective To study the effects of ephedrine and phenylepbedrine for maintenance of arterial pressure during combined spinai/epidural anesthesia (CSEA) for caesarean section. Methods Forty patients, ASA grade Ⅰ - Ⅱ, who were scheduled for caesarean section by CSEA were randomly divided into two groups, when patients were hypotension, phenylephedrine 100 μg (group P, 20 cases ) or ephedrine 10 mg (group E, 20 cases). The variety of blood pressure (Bp), heart rate (HR) and oxyhemoglobin saturation (SpO2) were monitored; recorded before anesthesia (T0), at 15 min after anesthesia (T1), fetuses were taken out of uterus (T2) and at the end of operation (T3); umbilical arterial blood gas analysis was monitored; neonatal Apgar score was investigated. Results Umbilical arterial blood gas analysis of pH,PaO2, PaCO2, HCO3-, SaO2 were normal in two groups, there were no significant difference in PaO2, PaCO2 and SaO2 between two groups, but pH and HCO3- in group P were higher than those in group E [7.38±0.07 vs7.30±0.02 and (21.5±3.4) mmol/L vs (19.3±3.3) mmol/L] (P <0.05). There were no significant difference in Apgar score and Bp between two groups. Compared with group P, the HR in group E was increased obviously at T1 and T2 (P < 0.05). Conclusion Phenylephedrine is the vasopresser that most closely meets the criteria for the best vasopressor to use in obstetric patients.
ABSTRACT
Twenty-six total intravenous anesthesia was performed in 23 ASAⅡorⅢpatients with various advanced malignancies undergoing whole body hyperthermia (WBH). Their age ranged from 32 to 67 yrs and body weight between 42 and 77 kg. The patients had no hypertension, coronary artery disease or diabetes mellitus. Anesthesia was induced with midazolam 5-10 mg, fentanyl 0.1 mg, propofol 1.5-2.5 mg?kg-1 and vecuronium 0.12 mg?kg-1 and maintained withⅣinfusion of midazolam (0.08-0.16 mg?kg-1?h-1), remifentanil (0.05-0.15?g?kg-1?h-1) and vecuronium (0.08-0.15 mg?kg-1?h-1). The patients were mechanically ventilated (VT = 8-12 ml?kg-1, RR= 10-18 bpm, FiO2 = 1.0) after tracheal intubation. PETCO2 was maintained at 35 mm Hg. ECG, MAP, HR, CVP, SpO2 , PETCO2 , peak airway pressure, VT, RR, minute ventilation (MV), urine output, core temperature (lower esophageal and naso-pharyngeal) and surface temperature were continuously monitored. Swan-Ganz catheter was placed in 15 patients. MPAP, PCWP and cardiac output (CO) were measured and Qs/Qt, cardiac index (CI) and stroke index (SI) were calculated. WBH was induced in an ultra-red radiation hyperthermic cabin (type ET-SpaceTM-1) and was divided into 3 phases:Ⅰwarming phase (lower esophageal temperature increased gradually to 41.8℃) ;Ⅱhyperthermic phase (lower esophageal temperature was maintained at 41.8℃for 1 h) andⅢcooling phase (core temperature was gradually decreased to 38.5℃without any cooling measures). Blood samples were taken from artery and Swan-Ganz catheter 15 min after induction of anesthesia (baseline), at 39℃, 40℃, 41℃and 41.8℃during warming phase, at the late hyperthermic phase and at 40℃and 38.5℃during cooling phase for blood gas analysis, determination of blood electrolytes and sugar. As the temperature was increasing, HR, CI, SI, CVP, MPAP, PCWP, Qs/Qt and peak airway pressure were gradually increased while MAP, PaO2 , pHa, BE and blood glucose and K+ were decreasing during warming phase (Ⅰ). These changes reached the peak levels at the late period of hyperthermic phase (Ⅱ) and then gradually returned to baseline during cooling phase (Ⅲ) . Vasoactive drugs and fluid infusion including crystalloid and colloid were needed to maintain hemodynamic stability in 69% patients. Acidosis had to be corrected in 54% patients. Severe hypotension and pulmonary edema occurred in 4 patients. Continuous hemodynamic monitoring, respiratory support, maintenance of circulatory stability and correction of acidosis and hypokalemia were the key factors in the management of patients during WBH.