No abstract available.
Adolescent* ; Humans

The deliberate hypotension with esmolol or sodium nitroprusside(SNP) was provided subsequently in random order with six dogs. Anesthesia was maintained with 0.8 vol% halothane, end-tidal, in N2O/O2, 50: 50, with vecuronium. Mean arterial pressure was reduced 30-35% to 70 mmHg, with use of SNP or esmolol. Mean arterial pressure, heart rate, mean pulmonary arterial pressure, arterial blood gas analysis, and cardiac output were measured both prior to the deliberate hypotension and at 70 mmHg of mean arterial pressure induced with esmolol or SNP. The following results were observed; 1) The mean doses required were 725+/-250 ug/kg/min in esmolol and 12+/-2 ug/kg/min in SNP. 2) Esmolol was associated with a decrease in cardiac output (from 2.13+/-0.23 to 1.27+/-0.23 L/min), in heart rate (from 128+/-14 to 91+/-11/min), and an increase in central venous pressure (from 9.2+/-3.27 to 11.60+/-3.21 mmHg)(p<0.05). 3) SNP decreased systemic vascular resistance from 41111+/-484 to 2175+/-451 dynessec/cm5 (P<0.05), trended to increase heart rate. 4) A change in arterial blood gas analysis before and during deliberate hypotension with esmolol or SNP was not significant. As to mechanism of hypotensive effect, SNP caused decrease in systemic vascular resistance by 47% but esmolol significantly reduced cardiac output by 40% and heart rate by 29%. The result of present study suggests that when moderately deliberate hypotension with only esmolol was done, the potential for marked myocardial depression must be recognized. The differences in pharmacologic properties for the different hypotensive agents suggest that combinations of these agents may be provide a pharmacologic profile superior to either agent alone.
Anesthesia ; Animals ; Arterial Pressure ; Blood Gas Analysis ; Cardiac Output ; Central Venous Pressure ; Depression ; Dogs* ; Halothane ; Heart Rate ; Hemodynamics* ; Hypotension* ; Nitroprusside* ; Sodium* ; Vascular Resistance ; Vecuronium Bromide

Transient increases in blood pressure and heart rate(HR) at the end of anesthesia and during extubation are common. Tomori and Widdicombe observed that mechanical stimulation of four areas of the upper respiratory tract (nose, epipharynx, laryngopharynx, tracheobnchial tree) induced reflex cardiovascular responses associated with enhanced neuronal activity in the cervical sympathetic efferent fibers. In susceptible patients, even this short period of hypertension and tachycardia can result in myocardial ischemia or increased intracranial pressure. The purpose of present study was to evaluate the effect of esmolol in attenuating cardiovascular responses to extubation under general anesthesia with endotracheal intubation. A sixty healthy patients who underwent elective noncardiac operation under general anesthesia (N2O-O2-enflurane) with endotracheal intubation were randomly divided into two groups : one was placebo group that received intravenous injection of 0.1 cc/kg normal saline, the other was esmolol group that received intravenous injection of 1 mg/kg esmolol. Extubation was performed when the patients could breathe spontaneously and open their eyes on command. In practice extubation was done between 2 and 4 minutes after drug(esmolol or saline) injection. The measurement of systolic blood pressure and heart rate was obtained one minute before extubation and every minute for 5 minutes after extubation, then rate-pressure product was calculated. The results were as follows; 1) When compared to pre-extubation systolic blood pressure, systolic blood pressure for 2 minutes after extubation in both groups increased significantly but systolic blood pressure was more rapidly returned to pre-extubation level in the esmolol group than in the placebo group. When compared to pre-extubation systolic blood pressure, after extubation the number of patients in whom systolic blood pressure increased more than 20% was significantly fewer in the esmolol group than in the saline group. 2) When compared to pre-extubation heart rate, heart rate at 1 minute after extubation in the placebo group increased significantly but heart rate after extubation in the esmolol group did not change significantly. 3) When compared to pre-extubation rate-pressure product, rate-pressure product for 2 minutes after extubation in both group increased significantly. At 4 minutes after extubation, rate-pressure product in the saline group increased significantly when compared to rate-pressure product in the esmolol group. These results suggest that intravenous injection of 1 mg/kg esmolol before extubation blocks heart rate elevation following extubation under general anesthesia and is effective for rapid return to the pre-extubation level of systolic blood pressure.
Anesthesia ; Anesthesia, General ; Blood Pressure ; Heart ; Heart Rate ; Humans ; Hypertension ; Hypopharynx ; Injections, Intravenous ; Intracranial Pressure ; Intubation, Intratracheal ; Myocardial Ischemia ; Neurons ; Reflex ; Respiratory System ; Tachycardia

Acetabular bone deficiencies encountered during the revision hip arthroplasties should be recon- structed to provide the implant stability and to restore the normal center of rotation of hip and the leg length. We revised the loosened acetabular cup by grafting fresh-frozen bulk femoral head and inserting uncemented cup in 17 hips of 15 patients. The average follow-up period was 2 years and 3 months. The acetabular bone deficiencies were type 2A in 6 hips, type 2B in 8, type 3A in 1 and type 3B in 2 by Paprosky's classification. Three blocks of femoral head were grafted in 3 type 3 deficiencies, but only one in type 2 deficiencies. The cup-host bone contact was 41% on the average. However, the cup-host bone contact in the zone I was present only in 12 out of 17 hips and its average was 14%. Incorporation of the allograft into the host bone occurred between 5 months and 1 year and 7 months (average, 8,6 months) after revision surgery. Significant radiographic loosening sign was noted only in 2 hips which had not only type 3B bone deficiencies reconstructed with 3 blocks of femoral head allograft but also no cup-host bone contact in zone I . The bulk allograft of fresh-frozen femoral head demonstrated acceptable results in type 2 acetabular bone deficiencies, although the follow-up period was relatively short. Reconstruction of type 3B acetabular bone deficiencies by using multiple blocks of femoral head allograft had been failed. We presumed that the lack of the graft stability and the intimate contact between the grafts and host bone was the cause of failure.
Acetabulum* ; Allografts* ; Arthroplasty ; Classification ; Follow-Up Studies ; Head* ; Hip ; Humans ; Leg ; Transplants

No abstract available.
Child* ; Humans ; Joints* ; Tuberculosis, Osteoarticular*

Adenosine triphosphate-sensitive potassium channel (KATP channel) closed by intracellular adenosine triphosphate (ATP) appears widely distributed in the vascular system. Activation of vascular smooth muscle KATP channel with hyperpolarizing agents such as lemakalim results in membrane hyperpolarization, a consequent reduction in calcium influx through voltage-dependent calcium channel, and leads to vessel relaxation. In contrast to KATP channel activation in vascular smooth muscle cell, KATP channel-induced hyperpolarization of endothelial cells results in an increase in calcium influx, which could stimulate the production of nitric oxide and prostacyclin from the endothelial cell. KATP channels response to change in the cellular metabolic status like ischemia and hypoxia, and are the target of a variety of synthetic and endogenous vasoactive substance. KATP channel openers are used as therapeutic agent for cardiovascular disease. Endogenous KATP channel-induced vasodilation is functionally important because it has been shown to modulate the pulmonary vasoconstrictor response to hypoxia and systemic hypotension in the pulmonary circulation, enhance tissue perfusion in response to hypoxia and severe hypotension in the systemic circulation. In virtro, halothane and intravenous anesthetics attenuated KATP channel agonist, lemaklim-induced vasodilation. The coronary vasodilation by volatile anesthetics such as isoflurane, enflurane and halothane was associated with activation of KATP channel in coronary artery. Further investigation is required to determine signal transduction pathway in detail stimulated by KATP channel agonist in human blood vessel and effect of anesthetics on the KATP channel-induced signal transduction, and role of KATP channel of pathophysiology of vascular disease such as hypertension, angina.
Adenosine Triphosphate* ; Adenosine* ; Anesthetics* ; Anesthetics, Intravenous ; Anoxia ; Blood Vessels ; Calcium ; Calcium Channels ; Cardiovascular Diseases ; Coronary Vessels ; Cromakalim ; Endothelial Cells ; Enflurane ; Epoprostenol ; Halothane ; Humans ; Hypertension ; Hypotension ; Ischemia ; Isoflurane ; KATP Channels ; Membranes ; Muscle, Smooth, Vascular* ; Nitric Oxide ; Perfusion ; Potassium Channels* ; Potassium* ; Pulmonary Circulation ; Relaxation ; Signal Transduction ; Vascular Diseases ; Vasodilation

BACKGROUND: Type 2 diabetes is usually preceded by a long and clinically silent period of increasing insulin resistance. The purpose of this study is to demonstrate that rosiglitazone and metformin fixed-dose combination therapy (RSG/MET) will safely and effectively control glycemia as a first line of oral therapy, better than rosiglitazone (RSG) or metformin (MET) monotherapy in Korean type 2 diabetes patients. METHODS: This study was a 32-week, multicenter, randomized, double-blind study. Twenty-seven type 2 diabetes patients (males 14; females 13) were included and randomly divided into the rosiglitazone, metformin group, or rosiglitazone /metformin combination groups. The primary objective of this study was to determine the change in HbA1c from baseline (week 0) to week 32. The secondary end-points were to determine changes in fasting plasma glucose (FPG) and homeostasis model assessment insulin resistance (HOMA-IR), from baseline to week 32. Other cardiovascular risk markers were also assessed. RESULTS: At week 32, there were significant reductions in HbA1c and FPG, in all three treatment groups. There was no statistical difference in HbA1c among the three groups, but the decrease in FPG in the RSG/MET group was statistically significant compared to the MET group (P < 0.05). RSG/MET significantly reduced HOMA-IR at week 32 compared to baseline, but there was no difference among the three groups. RSG/MET significantly decreased high-sensitive C-reactive protein (hs-CRP) value at week 32, compared to baseline. There were increases in adiponectin from baseline to week 32 in the RSG and RSG/MET groups, and the increase in the RSG/MET group was statistically significant compared to that of the MET group (P < 0.05). At week 32, there was a significant decrease in plasminogen activator inhibitor-1 (PAI-1) in all three treatment groups, but no statistically significant difference among them. The RSG/MET group significantly decreased in terms of urinary albumin-creatinine ratio at week 32, compared to baseline. CONCLUSIONS: In this study, rosiglitazone and metformin combination therapy was effective in glycemic control as an initial therapy, and it improved cardiovascular risk markers in Korean type 2 diabetes patients.
Adiponectin ; C-Reactive Protein ; Diabetes Mellitus, Type 2 ; Double-Blind Method ; Fasting ; Female ; Glucose ; Homeostasis ; Humans ; Insulin Resistance ; Metformin ; Plasma ; Plasminogen Activators ; Thiazolidinediones

BACKGROUND: Since a change in venous capacitance significantly alters venous return and thus affects cardiac output, it is important to know the effects of vasodilators on venous capacitance. The purpose of this study was to examine the effects of sodium nitroprusside and nitroglycerin on venous capacitance during induced hypotension in halothane anesthetized dogs. METHODS: Fourteen mongrel dogs(SNP group: 7, NTG group: 7), weighing 10~15 kg, were anesthetized with N2O 1.5L/min-O2 1.5L/min-halothane 0.5vol%. Each dog received only one drug. In dogs anesthetized with N2O-O2-halothane, mean arterial pressure(MAP) was decreased by 15%(mild hypotension) and 30%(deep hypotension) of control value by sodium nitroprusside(SNP) and nitroglycerin (NTG), respectively. Venous capacitance was assessed before and during induced hypotension by measuring mean circulatory filling pressure(MCFP). MCFP was measured after arresting the circulation by tightening of superior vena cava and inferior vena cava snares simultaneously. RESULTS: As compared with MCFP before induced hypotension, MCFP was significantly decreased by SNP at deep hypotension and NTG at mild hypotension and deep hypotension. As compared with MCFP at mild hypotension, MCFP at deep hypotension was significantly decreased by NTG and SNP, respectively. CONCLUSIONS: These results suggest that NTG has potent venodilating effect at mild and deep induced hypotension, whereas SNP has venodilating effect only at deep induced hypotension.
Animals ; Cardiac Output ; Dogs* ; Halothane* ; Hypotension* ; Nitroglycerin* ; Nitroprusside* ; Pharmacology ; SNARE Proteins ; Sodium* ; Vasodilator Agents ; Vena Cava, Inferior ; Vena Cava, Superior

BACKGROUND: Obese type 2 diabetic subjects are recently increasing in Korea, indicating the importance of insulin resistance rather than insulin secretory defects in the pathophysioloy of type 2 diabetes. The purpose of this study is to evaluate the safety and efficacy of fixed dose rosiglitazone/metformin combination therapy in poorly controlled subjects with type 2 diabetes mellitus. METHODS: 12 type 2 diabetic subjects who had a HbA1c > 11% or fasting plasma glucose > 15 mmol/L were included. After a 2 week screening period, the subjected took the fixed does rosiglitazone/metformin for 24 weeks. The treatment with rosiglitazone/metformin began at week 0 with an initial dose of 4 mg/1000 mg and, unless tolerability issues arose, subjects would be increased to 6 mg/1500 mg at week 4 and at week 8 to the maximum dose of 8 mg/2000 mg. The primary object of this study was to characterize the magnitude of HbA1c reduction from baseline after 24 weeks of rosiglitazone and metformin treatment in poorly controlled type 2 diabetics. RESULTS: The mean age of the subjects was 48.9 +/- 10.6 years old, body mass index was 25.0 +/- 3.5 kg/m2, HbA1c was 12.0 +/- 1.0%, and fasting plasma glucose was 16.3 +/- 3.1 mmol/L. HbA1c was reduced to 7.54 +/- 1.45% and fasting plasma glucose reduced to 7.96 +/- 2.38 mmol/L at week 24. The proportion of HbA1c responder who showed the reduction from baseline of > or = 0.7% or HbA1c < 7% was 11 among 12 subjects (91.7%). 41% of the subjects (5 among 12 subjects) achieved HbA1c level < 7.0% and 75% (9 among 12 subjects) achieved HbA1c level < 8.0%. CONCLUSIONS: In this study, rosiglitazone and metformin combination therapy was effective in glycemic control in poorly controlled subjects with type 2 diabetes mellitus.
Body Mass Index ; Diabetes Mellitus, Type 2 ; Fasting ; Glucose ; Insulin ; Insulin Resistance ; Korea ; Mass Screening ; Metformin ; Plasma ; Thiazolidinediones