The effect of spinal anesthesia on pulse oximetry / 대한마취과학회지

BACKGROUND: Pulse oximetry provides valuable data on the arterial oxygen saturation. Significant impairment in the arterial oxygen saturation can occur under vasoconstriction, hypothermia, and hypotension. This study compared the percutaneous oxygen saturation (SpO2) at the hand and the foot with the arterial oxygen saturation (SaO2) during spinal anesthesia. METHODS: Twenty eight, ASA physical status 1 or 2, patients received a spinal block with 0.5% hyperbaric bupivacaine. Two pulse oximeter probes were applied to the index finger and second toe of the patients, and the SpO2 values were recorded before, 10, 20, and 30 minutes after the intrathecal injection. The SaO2 was measured before and 30 minutes after the intrathecal injection. RESULTS: During spinal anesthesia, there were similar changes in the SpO2 value from the hand. However, there was a progressive decrease in SpO2 of the foot of 97.6 +/- 2.8%, 97.3 +/- 2.8%, and 97.2 +/- 3.3% at 10, 20, and 30 minutes, respectively (P < 0.05 compared with the baseline). There were significant differences between the hand and foot SpO2 in 20 and 30 minutes (0.79 +/- 1.55%, 0.93 +/- 1.86%) after the intrathecal injection. The SaO2 value was similar before and 30 minutes after the intrathecal injection. Before spinal anesthesia, there were significant differences between the SaO2 (96.4 +/- 2.6%) and SpO2 values of the hand (98.1 +/- 2.6%) and the foot (98.3 +/- 2.6%). CONCLUSIONS: During spinal anesthesia, it is appropriate to measure the SpO2 from the hand because it dose not change significantly.

The Effect of Desflurane with Remifentanil for Hemodynamic Responses to Skin Incision

BACKGROUND: Desflurane can induce sympathetic nervous activity and increase mean arterial blood pressure and heart rate, especially when used above the concentration of MAC-BAR. Opioids can reduce this response during general anesthesia. We compared the effect of the use of 1 ng/ml remifentanil and 50% N2O with 1 MAC desflurane for cardiovascular responses to skin incision with the effects of the use of sevoflurane. METHODS: We recruited 47 patients with ages between 20 and 60 years, and ASA physical status 1, who were scheduled for appendectomy surgery under general anesthesia. The patients were divided into two groups. Anesthesia was induced with remifentanil (target-controlled effect-site concentration of 2 ng/ml), 2 mg/kg propofol and 0.7 mg/kg rocuronium. After tracheal intubation, anesthesia was maintained as follows. Group D (desflurane) was administered an end-tidal concentration of 4.0% desflurane with remifentanil (target-controlled effect-site concentration of 1 ng/ml) and 50% N2O. Group S (sevoflurane) was administered an endtidal concentration of 1.1% sevoflurane with remifentanil (targetcontrolled effect-site concentration of 1 ng/ml) and 50% N2O. The mean arterial blood pressure and heart rate were measured at baseline, after tracheal intubation, every minute for 3 minutes before skin incision, and for 5 minutes after skin incision. RESULTS: There was no difference in the changes of mean arterial blood pressure and heart rate between the patients in the two groups before and after skin incision. CONCLUSIONS: As with sevoflurane, the addition of 1 ng/ml remifentanil to 1 MAC desflurane and 50% N2O can effectively blunt the cardiovascular responses to skin incision.

The Effect of Folate Defficiency on Plasma Cholesterol and Antioxidative System in Ethanol-fed Rats

Chronic alcoholism is considered a common cause of malnutrition. Especially, micronutrient deficiency may playa critical role in the incidence of alcoholic liver diseases. This study was conducted to investigate the effect of folate deficiency and ethanol consumption on cholesterol metabolism and the antioxidative system in rats. Plasma concentration of total cholesterol was increased by ethanol administration in folate-fed rats. HDL-cholesterol tended to be higher in the folate-fed group, but it was not significant. The plasma and hepatic levels of malondialdehyde were increased after chronic ethanol feeding, but dietary folate depressed the plasma malondialdehyde content of rats. Ethanol or folate feeding did not significantly change alcohol dehydrogenase activity. But folate feeding increased catalase activity in ethanol-fed rats. There was no significant change in superoxide dismutase activity among the experimental groups. Glutathione peroxidase activity tended to decrease by chronic ethanol feeding, but dietary folate did not affectthe glutathione peroxidase activity of chronic ethanol-fed rats. Glutathionine-S-transferase activity was not affected by ethanol feeding or folate deficiency. The plasma and hepatic levels of retinol decreased after chronic ethanol feeding. The hepatic level of retinol significantly decreased in ethanol-fed rats by folate deficiency. The plasma level of alpha-tocopherol tended to be low in the folate deficient group with ethanol feeding, but there was no difference among the experimental groups in the hepatic level of alpha-tocopherol. These results demonstrate that chronic ethanol consumption changes the plasma cholesterol metabolism and antioxidative system of rats, and optimal folate feeding in ethanol-fed rats exerts protective effects to some extent.