BACKGROUNDEpinephrine infiltration of the nasal mucosa causes hypotension during functional endoscopic sinus surgery (FESS) under general anesthesia. A prospective randomized-controlled study was designed to determine whether relatively light general anesthesia is superior to fluid expansion in reducing epinephrine-induced hypotension during FESS.

METHODSNinety patients undergoing elective FESS under general anesthesia were randomly assigned to three groups with 30 patients in each. Each patient received local infiltration with adrenaline-containing (5 microg/ml) lidocaine (1%, 4 ml) under different conditions. For Group I, anesthesia was maintained with propofol 2 microg/ml and rimifentanil 2 ng/ml by TCI. Group II (control group) and Group III received propofol 4 microg/ml and rimifentanil 4 ng/ml, respectively. In Groups I and II, fluid expansion was performed with hetastarch 5 ml/kg within 20 minutes; hetastarch 10 ml/kg was used in Group III. Mean arterial pressure (MAP) and heart rate (HR) were recorded at 30-second-intervals for 5 minutes after the beginning of local infiltration. Simultaneously, the lowest and the highest MAP were recorded to calculate the mean maximum increase or decrease percent in MAP for all patients in each group. Data analysis was performed by chi(2) test, one-way analysis of variance, or one-way analysis of covariance.

RESULTSHemodynamic changes, particularly a decrease in MAP accompanied by an increase in HR at 1.5 minutes (P < 0.05), were observed in all groups. The mean maximum decrease in MAP below baseline was 14% in Group I, 24% in Group III and 26% in Group II. There were statistically significant differences between Group I and Groups II and III (P < 0.05). The mean maximum increase in MAP above baseline was 9% in Group I, 6% in Group III and 2% in Group II.

CONCLUSIONRelatively light general anesthesia can reduce the severity of epinephrine-induced hypotension more effectively than fluid expansion during FESS under general anesthesia.

Adolescent ; Adult ; Anesthesia, General ; Endoscopy ; Epinephrine ; adverse effects ; Female ; Humans ; Hypotension ; chemically induced ; prevention & control ; Male ; Middle Aged ; Paranasal Sinuses ; surgery ; Plasma Volume ; Prospective Studies

We designed a randomized, double-blinded study to determine the efficacy and safety of 0.5 mg/kg intravenous ephedrine for the prevention of hypotension during spinal anesthesia for cesarean delivery. Patients were randomly allocated into two groups: ephedrine group (n=21) and control group (n=21). Intravenous preload of 15 mL/kg lactated Ringer's solution was given. Shortly after the spinal injection, ephedrine 0.5 mg/kg or saline was injected intravenous for 60 sec. The mean of highest and lowest heart rate in the ephedrine group was higher than those of control group (P<0.05). There were significant lower incidences of hypotension and nausea and vomiting in the ephedrine group compared with the control group (8 [38.1%] vs. 18 [85.7%]); (4 [19%] vs. 12 [57.1%], respectively) (P<0.05). The first rescue ephedrine time in the ephedrine group was significantly longer (14.9+/-7.1 min vs. 7.9+/-5.4 min) than that of the control group (P<0.05). Neonatal outcome were similar between the study groups. These findings suggest, the prophylactic bolus dose of 0.5 mg/kg intravenous ephedrine given at the time of intrathecal block after a crystalloid fluid preload, plus rescue boluses reduce the incidence of hypotension.
Adult ; *Anesthesia, Spinal/adverse effects ; Blood Pressure/drug effects ; *Cesarean Section ; Ephedrine/administration & dosage/*therapeutic use ; Female ; Heart Rate/drug effects ; Humans ; Hypotension/chemically induced/prevention & control ; Injections, Intravenous ; Postoperative Nausea and Vomiting/prevention & control ; Pregnancy ; Vasoconstrictor Agents/administration & dosage/*therapeutic use