Core Temperature Changes according to Premedication / 대한마취과학회지

BACKGROUND: It is well known that body core temperature reduces during general anesthesia. Midazolam premedication for relieving anxiety might also reduce body core temperature by inhibiting tonic thermoregulatory vasoconstriction in elderly patients. Therefore, an effort to maintain temperature must be started before anesthesia. This study was designed to evaluate the effect on body core temperature of midazolam, atropine and glycopyrrolate, which are commonly used for premedication. METHODS: Six hundred and eleven patients of ASA physical status 1 or 2, aged 18 to 65, were involved in this study. They were randomly assigned to premedication with: 1) saline control (n = 92); 2) midazolam 0.04 mg/kg (n = 96); 3) midazolam 0.04 mg/kg with glycopyrrolate 0.004 mg/kg (n = 117); 4) midazolam 0.04 mg/kg with atropine 0.01 mg/kg (n = 93); 5) glycopyrrolate 0.004 mg/kg (n = 116); and 6) atropine 0.01 mg/kg (n = 97). All premedication was given intramuscularly about 30 min before operation. Temperatures were measured at the tympanic membrane at the time of premedication and 30 min after premedication. RESULTS: Temperatures increased slightly after injection in the control (0.14 +/- 0.36oC; mean +/- SD) and this increase was less in the midazolam group (0.07 +/- 0.39oC). The changes of temperature in the midazolam with glycopyrrolate (0.16 +/- 0.39oC), midazolam with atropine (0.19 +/- 0.40oC), and in the glycopyrrolate group were no different from that of the control group. However, there was a statistically significant increase in temperature after injection in the atropine group (0.26 +/- 0.42oC) versus the control group. Compared with the midazolam group, a statistically significant increase in temperature was observed in the midazolam with atropine, the glycopyrrolate, and in the atropine group. CONCLUSIONS: From these results, low dose midazolam (0.04 mg/kg), midazolam with glycopyrrolate, and midazolam with atropine for premedication have little affect on temperature. Midazolam with glycopyrrolate premedication is recommended for preserving body core temperature.

Atrial Fibrillation Treated by Propafenone during Induction of General Anesthesia: A case report / 대한마취과학회지

We experienced a case of unexpected atrial fibrillation (AF) developed during induction of general anesthesia. The patient was a 71-year-old woman diagnosed with a cerebral aneurysm. She had no history of heart or lung disease. Preoperative laboratory results, chest x-ray, arterial blood gas analysis and vital signs were within normal limits except ST and T changes in a preoperative ECG. Preoperative echocardiography showed left heart enlargement but other findings were nonspecific. AF combined with decreased blood pressure and increased heart rate developed during induction of general anesthesia. Digoxin and esmolol were given for heart rate control. Propafenone was used for chemical cardioversion through a naso-gastric tube. Thirty minutes after medication, AF disappeared and vital signs returned to the preoperative condition.