Effect of Hemodilution on Brain Damage after Focal Cerebral Ischemia in Rabbits / 대한마취과학회지

BACKGROUND: Hemodilution after focal cerebral ischemia increases cerebral blood flow to ischemic brain tissue and reduces neurologic injury. With rare exceptions, most studies have reduced hematocrit (Hct) to no less than 30%. We studied the effect of moderate hemodilution (hematocrit 27%) on cerebral infarct volume after focal cerebral ischemia in rabbits. METHODS: Twenty rabbits were divided into a control group (n = 10) and a hemodilution group (n = 10). In the control group, cerebral infarction was induced by embolization of the middle cerebral artery using an autologous blood clot without hemodilution. In the hemodilution group (n = 10), hemodilution of around hematocrit 27% was achieved by exchanging arterial blood with 10% hydroxyethyl starch 1 hour before embolization of the middle cerebral artery in the hemodilution group. Seven hours after embolization, coronal brain slices were made with 2 mm thickness at 1 cm from the frontal pole and stained with 2% 2,3,5-triphenyltetrazolium chloride. The infarct volume was quantitated by image analysis of photography of the infarcted area. RESULTS: The infarct volume of the cerebral hemisphere (25.9 +/- 8.9%), subcortex (16.3 +/- 3.1%) in the hemodilution group was significantly smaller than in the control group (34.9 +/- 8.9%, 19.3 +/- 5.1%) (P<0.05), but, in the cortex, the difference of infarct volume is not statistically significant between the control group (23.5 +/- 11.9%) and the hemodilution group (15.6 +/- 2.7%). CONCLUSIONS: These results indicate that moderate hemodilution (hematocrit 27%) reduces neurologic injury after focal cerebral ischemia.

The Influence of Varying Dose and Lockout Interval on Patient-controlled Analgesia Using Meperidine / 대한마취과학회지

BACKGROUND: The lockout interval is a safe guard to prevent patients from taking additional dose before the full effect of the preceding dose. Therefore, it should correlate with the time-to-peak effect of the opioid selected. The time-to-peak effect of meperidine is known to be different from that of morphine and fentanyl. But there have been few reports about the influence of varying lockout interval on IV-PCA using meperidine. So we studied the influence of varying lockout interval with constant hourly maximum dose on IV-PCA using meperidine. METHODS: This study included sixty patients undergoing low abdominal surgery under general anesthesia. After administration of initial dose of meperidine (0.5 mg/kg) they were randomly assigned to three groups according to the lockout interval; Group 1 (6-min lockout interval, 0.2 mg/kg bolus dose), Group 2 (9-min lockout interval, 0.3 mg/kg bolus dose), Group 3 (12-min lockout interval, 0.4 mg/kg bolus dose). We examined NRS pain score, sedation score, satisfaction score, PCA measurements and the incidence of side effects during 24 hours. RESULTS: There were no significant differences in NRS pain score, sedation score, satisfaction score, the amount of meperidine consumed, injections/attempts ratio and the incidence of side effects among three groups. The numbers of injections and attempts were significantly higher in Group 1 than in Group 2 and Group 3 (P<0.05). CONCLUSIONS: The lockout intervals chosen for this study (6-min, 9-min, 12-min) do not influence pain, side effects, satisfaction and meperidine consumption in IV-PCA using meperidine when hourly maximum dose is constantly 2 mg/kg.

Peripheral Effect of Morphine on Mechanical Allodynia in a Rat Model of Neuropathic Pain / 대한마취과학회지

BACKGROUND: The therapeutic effect of morphine on neuropathic pain states was controversial, but there are some reports that systemic morphine reduced pain. Recently, many investigators have reported that locally administered morphine alleviated pain in local inflammatory pain model. Therefore, we designed this study to evaluate the peripheral effect of morphine and its antagonism by naloxone in rats experiencing neuropathic pain. METHODS: Neuropathic pain was produced by tightly ligating the left 5 th and 6 th lumbar spinal nerves of male Spraw-Dawley rats. To evaluate the systemic effect, morphine 200 microgram was injected into the unaffected right paw. Morphine 50, 100 and, 200 microgram were injected into the affected left paw. Naloxone 5, 10 and 20 microgram were injected into the affected left paw ten minutes before morphine 200 microgram was injected into the affected left paw. Before and after drug injection, mechanical allodynia was quantified by the foot withdrawal frequency to von Frey filaments of 5.50 g or 1.48 g, applied to the affected left paw. RESULTS: Morphine 200 g injected into the unaffected right paw did not affect the foot withdrawal frequency on the affected left paw. Morphine 100 and 200 microgram decreased the foot withdrawal frequency. In rats with morphine 200 microgram injected into the left paw, naloxone 5, 10, and 20 microgram increased foot withdrawal frequency. Conclusion: These data represented that morphine injected into the affected paw dose-relatedly reduced mechanical allodynia via peripheral effect and pretreatment of naloxone significantly antagonized the morphine effect.

The Effect of Intraperitoneal Hyperthermic Perfusion on the Postoperative Liver Function in Cancer Patient / 대한마취과학회지

BACKGROUND: Intraperitoneal hyperthermic perfusion (IPHP) has been introduced in clinical practice to improve the survival of cancer patients. But despite of this advantage, postoperative hepatic dysfunction may occur more severely after IPHP than general anesthesia. The protective mechanism of liver is destroyed by hyperthermia as the result. The purpose of this study is to evaluate the effect of intraperitoneal hyperthermic perfusion on the postoperative liver function in cancer patients. METHODS: Sixty patients with ovarian cancer were divided into two groups; 30 patients undergone only radical hysterectomy (control group), and 30 patients undergone radical hysterectomy combined with IPHP (IPHP group). Anesthesia was performed with enflurane-N2O-O2 in both groups. Serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and albumin levels were evaluated before anesthesia, 1, 3, 5, 7, 10 and 14th days after surgery on both groups. RESULTS: Postoperative SGOT levels were increased on 1, 3, 5, 7, 10 and 14th days in both groups, and on 1, 3 and 5 days postoperatively were increased more significantly in IPHP group than control group, but there were no significant difference between both groups after post-operative 7 days. SGPT levels were increased more significantly on 1, 3 and 5 days postoperatively in IPHP group than control group. Albumin levels were decreased more significantly on 1 and 3 days postoperatively in IPHP group than control group. CONCLUSION: We consider that postoperative liver function in cancer patients is influenced by the intraperitoneal hyperthermic perfusion.

Does Heparin Reduce Neurologic Injury in Rabbits That Occurs From Air Emboli? / 대한마취과학회지

BACKGROUND: Neurological injury after cerebral air embolism may be due to thromboinflammatory responses at sites of air-injured endothelium. Because heparin inhibits multiple thromboinflammatory processes. we hypothesized that heparin would decrease neurological impairment after cerebral air embolism. METHODS: Anesthetized rabbits received either heparin (n=14) or saline (n=13), 5 minutes before air injection (150 microliter/kg). Heparin was given as a 200 IU/kg bolus and followed by a constant infusion of 75 IU/kg/h for 2 hours. Equal volumes of salines were given to saline group. Two hours later, anesthesia was discontinued. Rabbits were neurologically evaluated 24 hours after air embolism. RESULTS: Heparin group had significantly less neurological impairment at 24 hours (34 14) than saline controls (52 8) (p=0.0013). CONCLUSIONS: When given prophylactically, heparin decreases neurological impairment caused by severe cerebral arterial air embolism.

Dosage Dependent Neurologic Impairment after Cerebral Air Embolism in Rabbit / 대한마취과학회지

BACKGROUND: A long-term objective is to understand the pathogenesis of neurologic injuries associated with cardiac surgery, cardiopulmonary bypass, and circulatory arrest. Our specific aims are to establish a dose of air which results in moderate to severe neurologic defects in normothermic (37degrees C) rabbits. METHODS: To first establish a dose of air which would cause unequivocal neurologic impairment, anesthetized rabbits received either 0, 50, 100 or 150 microgram l/kg of air into the internal carotid artery(n=5 in each group). One hour later, anesthesia was discontinued and animals were recovered. Animal were neurologically evaluated at 24 hours using a zero(normal) to 97(coma) point scale. RESULTS: There was a clear relationship between the dose of air injected and the severity of neurologic impairment at 24 hours, p=1.1x10(-7). Rabbits receiving 50 micrograml/kg of air were minimally affected and were difficult to distinguish from controls. In contrast, rabbits receiving 150 micrograml/kg of air were uniformly and unequivocally impaired. CONCLUSION: we recommend for future cerebral air embolism studies, 150 microgram l/kg as the optimal dose of air which would reliably produce viable subjects for 24 hours with marked unequivocal, neurologic impairment.

Anesthesia for Liver Transplantation / 대한마취과학회지

We experienced one case of anesthesia for liver transplantation in 32-year-old male patient with liver cirrhosis. The liver donor was 27-year-old male patient who was diagnosed brain death due to car accident. The operation was finished successfuly for 12 hours with intensive monitoring and treatrnent with using TEG and RIS. Patient was transfered to ICU after operation with intubated state. Extubation was done 2 days after operation and patient discharged without complication about 2 months later.