The Incidence of Hypoxia Following the Use of Hypnotics and Analgesics during Spinal Anesthesia / 대한마취과학회지

BACKGROUND: The purpose of this study was to find out the effect of hypnotics and analgesics on oxygen saturation by pulse oximetry in surgery patients under spinal anesthesia. METHODS: Sixty-five patients classified ASA physical status 1 or 2 scheduled for surgery under spinal anesthesia were studied. These patients were divided into three groups. The 22 subjects of the first group did not receive either midazolam or fentanyl. The 22 subjects of the second group received midazolam. The 21 subjects of the third group received midazolam (0.03 mg/kg) and fentanyl (1.0 microgram/ kg). Oxygen saturation was measured with a pulse oximetry. Measurements were made before spinal anesthesia, 5 minutes, and 10 minutes after starting of spinal anesthesia, 5 minutes, 10 minutes, 30 minutes, and 60 minutes after the start of the operation or intravenous injection of drugs. In addition, measurements were made on arrival in the recovery room, and 5 minutes, 10 minutes, 20 minutes, and 30 minutes after arrival in the recovery room. RESULTS: There were statistically significant differences in oxygen saturation at 5 minutes after the start of the operation or intravenous injection of drugs. The mean oxygen saturation for the first group was 98.2 +/- 1.8%, for the second group 97.9 +/- 2.6%, and for the third group 92.4 +/- 2.8%. Hypoxia cases at 5 minutes after the start of the operation or intravenous injection of a drug occurred in 4.5% of the first group, 9.1% of the second group, and 57.1% of the third group CONCLUSIONS: We concluded that oxygen saturation monitoring should be done routinely in patients receiving hypnotics and analgesics during spinal anesthesia, and oxygen should be administered to patients who develope hypoxia during spinal anesthesia.

Hypoxia from Erroneous Connection of a Nitrogen Tank for an Oxygen Tank: A case report / 대한마취과학회지

We present a case of hypoxia which occurred during the onset of general anesthesia in a small hospital. It was found that one of the oxygen tank which formed the central pipeline gas supply had been erroneously replaced by a nitrogen tank. Lack of strict observance of Compressed Gas Supply Standards by the gas supplier and the hospital personnel allowed it. We also emphasize that the oxygen analyzer should be counted as an essential monitor in every anesthesia. Oxygen analyzer detects the supply of intraoperative hypoxic gas admixture promptly and effectively.

Hypoxia from Erroneous Connection of a Nitrogen Tank for an Oxygen Tank: A case report / 대한마취과학회지

We present a case of hypoxia which occurred during the onset of general anesthesia in a small hospital. It was found that one of the oxygen tank which formed the central pipeline gas supply had been erroneously replaced by a nitrogen tank. Lack of strict observance of Compressed Gas Supply Standards by the gas supplier and the hospital personnel allowed it. We also emphasize that the oxygen analyzer should be counted as an essential monitor in every anesthesia. Oxygen analyzer detects the supply of intraoperative hypoxic gas admixture promptly and effectively.

Desaturation of Pulse Oximetry by Intraoperative Using of Subcutaneous Blue Dye: A case report / 대한마취과학회지

Pulse oximetry is a noninvasive, reusable device that is being used routinely in anesthesia procedure for monitoring oxygen saturation. This is a very beneficial device that can quickly detect of hypoxia, the most common cause of anesthesia-related death. However, in clinical uses, false desaturation readings are frequently found to be caused by various factors. Such as by the use of intraoperative blue dye, which can falsely decrease oxygen saturation as determined by pulse oximetry. We therefore report our findings concerning prolonged decreased pulse oximetry readings due to the intraoperative use of blue dye subcutaneously.

Comparison of Oxygen Saturation of Pulmonary Artery and Superior Vena Cava during Mitral Valve Replacement / 대한마취과학회지

BACKGROUND: Mixed venous oxygen saturation (SO2) has been considered as an important parameter during therapy of critically ill patients. But pulmonary artery catheterization for monitoring of SO2 involves risks and sometimes may be contraindicated. The purpose of this study was to evaluate whether SO2 could be replaced by oxygen saturation of superior vena cava (SvcO2). METHODS: We inserted pulmonary artery catheter in 38 patients scheduled for undergoing mitral valve replacement. Blood samples for SO2 were drawn from PA ports of pulmonary artery catheter, blood samples for distal SvcO2 were drawn from CVP ports of pulmonary artery catheter and blood samples for proximal SvcO2 were drawn from distal ports of sheat introducer. RESULTS: There was no significant difference between SO2 and SvcO2 (79.6% and 79.9%, 78.0%), and also no significant difference between distal and proximal SvcO2 (79.9%, 78.0%). Correlation of SO2 and SvcO2 was good (r=0.69: PA and SVCD, r=0.62: PA and SVCP). CONCLUSION: We conclude that mixed venous oxygen saturation might be replaced by oxygen saturation of superior vena cava during mitral valve replacement.