The Continuous Monitoring of Mixed Venous Oxygen Saturation for the Estimation of Cardiac Output Changes for Liver Transplantation in Dogs / 대한마취과학회지

BACKGROUND: In the management of liver transplantation, massive blood loss, interruption of venous retum to the heart, sudden infusion of acidic, cold and hyperkalemic blood from the graft, and uses of inotropic and vasoactive agents make cardiac output (CO) change unpredictably. We tried to find convenient method to estimate the change of CO by mixed venous oxygen saturation (SvO2) which can be monitored by pulmonary artery catheterization with fiberoptic oximeter using a spectrophotometer, By adapting the equation of oxygen transport and oxygen consumption(VO2), the equation CO=V/O2(Hbx0.134)x1/(SaO2-SvO2) can be obtained. If we assume the VO2 and hemoglobin concentration is constant and hypoxemia is excluded, CO might be proportional to I/(100-Sv O2). METHOD: For the management of orthotopic liver transplantations in 5 mongrel dogs, we continuously monitored Sv O2 with fiberoptic pulmonary catheter and intermittently measured the CO by thermodilution method according to operative phases. The Pearsons correlation coefficients between CO and mean arterial pressure, CO and S vO. and CO and 1/(100 SvO2) were measured in each dog. RESULT: The correlation coefficients between CO and 1/(100 SvO2) are raging from 0.74 to 0.98 with a corrected mean of 0.847 and significant in all dogs (p<0.05), and the correlation coefficients between CO and SvO2 are ranging from 0.67 to 0.96 with a corrected means of 0.786 and significant in 4 of 5 dogs. CONCLUSIONS: For the management of liver transplantation, the continuous monitoring of mixed venous oxygen saturation by a fiberoptic pulmonary catheter is helpful to detect changes of cardiac output.

The Relationship between Whole Body Oxygen Delivery and Oxygen Consumption in Anhepatic Phase of Canine Liver Transplantation / 대한마취과학회지

BACKGROUND: In patients of sepsis, especially combined with multiple organ failure syndrome, the whole body oxygen consumption is delivery dependent even above the critical oxgen delivery. This phenomenon is named as 'pathologic oxygen delivery dependency'. Multiple organ failure syndrome is characterized by maldistribution of oxygen delivery, tissue oxygen diffusion disturbance and inability of oxidative phosphorylation of anaerobic metabolites owing to hepatic failure. In liver transplantation, the anhepatic phase is characterized by uneven microperfusion due to surgical manipulation and 'total hepatic failure'. We hypothesized that there might be oxygen delivery dependency in anhepatic phase of liver transplantation. METHODS: In 14 canine orthotopic liver transplantations, whole body oxygen delivery (DO2) and oxygen consumption (VO2) were calculated as the product of cardiac output and, arterial oxygen content and arterial-venous oxygen content difference, respectively, according to the operative phases. Then the relationship between DO2 and VO2 was analyzed by correlation analysis in each operative phases. RESULTS: In control and four reperfusion phases no significant correlation was found. But in two anhepatic phases (10 minutes after inferior vena cava cross clamping, 5 minutes before reperfusion), significant correlation was found (R=0.79, 0.72, p<0.005, 0.01 repectively). In postinduction phase (50 minutes after induction), significant correlation was found (R=0.62, p<0.05), but strength of correlation was lower. CONCLUSIONS: This study showed the oxygen delivery dependency in anhepatic phase of liver transplantation. Therefore supranormal oxygen supply advocated in multiple organ failure syndrome and sepsis might be applicable to management of anhepatic phase of selected recipients.

Comparative Clinical Study of Pofol(Dong-guk Pharm Co.) with Diprivan(ICI Pharm Co.): Evaluation of Efficacy and Safety of Intravenous anesthetics "Pofol" / 대한마취과학회지

Propofol is a new, rapidly effective, short-acting intravenous sedative-hypnotic agent that can be used for induction and maintenance of general anesthesia. This study was performed to evaluate the efficacy and safety of domestic product Pofol in comparison with Diprivan for the management of total intravenous general anesthesia by double blind method. This study was approved by the Clinical Research Committee of SNUH. Test drugs were administered in a double-blinded fashion for the anesthesia. Seventy-four patients(aged 18-60 yr, operation time below two hours) were induced anesthesia with bolus injection of 2 mg/kg of test drug for 20 seconds and then anesthesia was maintained with continuous infusion method by syringe pump. Infusion dose of test drug during maintenance of anesthesia was controlled to maintain the systolic blood pressure measured at ward +/-20%. To evaluate the efficacy of drug, induction dose, mean maintenance dose, time to loss of conciousness after injection of induction dose and awakening time were measured or calculated. To evaluate the safety of drug, pain after injection of drug, recovery condition of patients and adverse events or side effects were recorded. Changes of blood pressure and heart rate were measured and arterial blood gas was also analyzed during perianesthetic period. There were no statistically significant differences in sex, age, weight, duration of anesthesia and ASA physical status distribution between Pofol group(P) and Diprivan group(D). There were no differences in induction dose and mean maintenance dose between P and D (mean+SD, 121+/-25 mg and 0.213+/-0.064 mg/kg/min vs 125+/-27 mg and 0.233+/-0.058 mg/kg/min, respectively). Time to loss of conciousness, time to response and time to orientation after cessation of drug were 14+/-19 sec, 10 min 2 sec+/-5 min 39 sec, 17 min 16 sec+/-9 min 43 sec for P and 14+/-26 sec, 12 min 52 sec+/-8 min 42 sec, 22 min 47 sec+/-14 min 17 sec for D. But there were no statistically differences between P and D, respectively. The incidence of pain after injection was 65.7% for P and 52.7% for D. Recovery from anesthesia was assessed as smooth in 82.9% for P and 91.7% for D. Adverse events during induction were recorded in four patients (apnea(1), opisthotonus(2) and hypotension(1)) for P and in two patients (apnea(1), bradycardia(l)) for D. The number of patients showed adverse events during maintenance of anesthesia and postanesthesia recovery period were same to P and D as 8 patients. Even though the characters of adverse events to P and D were different, the incidence rate was not different between two drugs. These adverse events were resolved without any specific treatment. In conclusion, there were no differences in efficacy and safety between Pofol and Diprivan.

Blood Pressure and Heart Rate Changes and the Patient Response following I.V. Administration of Fentanyl during Awake Fiberoptic Nasotracheal Intubation / 대한마취과학회지

The purpose of this prospective study was to evaluate the patient response and the changes of blood pressure and heart rate following intravenous administration of various dosage of fentanyl during awake fiberoptic nasotracheal intubation. After verbal informed consent, the 44 ASA status I or II patients undergoing oral and maxillofacial surgery were randomly assigned to receive 0(N=11), 1(N=11), 2(N=11), 3(N=l1) ug/kg of fentanyl, On arrival to operating room, midazolam 2 mg and glycopyrrolate 0.2 mg were administered for premedication. And then, EKG, blood pressure and peripheral O2 saturation were monitored continuously. Local anesthesia was induced with the gargling of 4% lidocaine 10ml, the transtracheal injection of 4% lidocaine 3ml and nasal spray 10% lidocaine 0.5ml. After that each dose of fentanyl was given to each groups. And then fiberoptic intubation was performed with continuous verbal contact to confirm the patient response and ventilatory status during intubation. During fiberoptic intubation, the peak level of blood pressure and heart rate were recorded. We compare the difference of blood pressure and heart rate between the value of just before fiberoptic intubation and the peak value during fiberoptic intubation and discomfort score according to fentanyl dosage on the first day of postoperation. The change of blood pressure and the time required for intubation was less and shortest in the 2 ug/kg of fentanyl group. But there were no significant differences in heart rate and discomfort score. We conclude that 2 ug/kg of fentanyl minimize the change of blood pressure as well as intubation time. But the change of dosage of fentanyl was not helpful to decrease the discomfort score.