No abstract available.
Adhesives*

Since the first report by Drury and Szent-Gyorgyi in 1929, the inhibitory influences of adenosine on the heart have repeatedly been described by many investigators. A lot of investigations on the working mechanisms of adenosine have been focused mainly on the effects on the coronary blood flow. However, the cellular mechanisms underlyiag the inhibitory action of adenosine on the SA node are not well understood yet. Furthe-rmore, the physiological role of adenosine in the regulation of the heart beat remains still to be explored. Thus, this study was undertaken to examine the behavior of the rabbit SA node ander the influence of adenosine, and the interactions between adenosine and aminophylline on the SA node, and then to compare these results with those of acetylcholine. At the same dosage range, adenosine suppressed the sinus rate and atrial contractility even in the reserpinized preparation. The spontaneous firing rate of the SA node at 35degrees C (mean+/-SEM, n=16) was 154+/-3.3 beats/min. The parameters of action potential were: maximum diastolic potential(MDP), -73+/-1,7 mV; overshoot(OS), 9+/-1.4 mV; slope of pacemaker potential(SPP), 94+/-3.0 mV/sec. Adenosine suppressed the firing rate of the SA node in a dose-dependent manner. This inhibitory effect appeared at the concentration of 10(-4)M and was potentiated in parallel with the increase in adenosine concentration. Changes in the action potential by adenosine were dose-dependent as show by the increase of MDP and the decrease of SPP until 10(-4)M. Above this concentration, however, the amplitude of the action potential decreased markedly due to the simultaneous decrease of both MDP and OS. Dipyridamole, which is known to block the adenosine transport aross the cell membrane, definately potentiated the action of adenosine. The effects of adenosine on the SA node were inhibited by aminophylline. However, the similar effects of acetylcholine to those of adenosine were not reversed by aminophylline. These results suggest that adenosine suppressed the pacemaker activity by acting dire-ctly on the membrane of the SA node, and the effects of adenosine on SA node are sele-ctively inhibited by aminophylline.
Acetylcholine ; Action Potentials ; Adenosine ; Aminophylline ; Cell Membrane ; Dipyridamole ; Fires ; Heart ; Humans ; Membranes ; Research Personnel

To evaluate the typical appearance and the influence in the image interpretation of the metallic artifact which is known as one of the patient-related field artifacts, we analysed the magnetic resonance (MR) images of 40 patients (the total number of metallic materials were 45) acquired at MR 1.5T unit. All patients were screened for the presence of metal. The metallic implants were surgical wires and clips, orthopedic devices, and the other miscellaneous materials. The artifacts produced by metallic objects can be seen on MRI as the focal loss of signal and/or the local distortion of the image. Regardless of their ferromagnetic properties, metallic implants created regional artifacts in their images. Ferromagnetic materials, such as a lead fragment, showed severe artifacts and nonferromagnetic metals showed mild to moderate artifacts. The conspicuity of artifact was related tot he composition, mass, shape, orientation, and the location of the metallic objects in the body. Under high magnetic field strength, there were no significant differences between the various pulse sequences. Artifacts are particularly prominent on gradient-echo images. Our findings indicate that MR imaging of patients with standard nonferromagnetic metallic materials can be successfully performed and usefully interpretated.
Artifacts* ; Humans ; Magnetic Fields ; Magnetic Resonance Imaging* ; Magnets ; Metals ; Orthopedics

Spontaneous pneumothorax is a known, but relatively rare complication of pulmonary metastases of sarcoma. A 19-year-old man was presented with chest pain and dyspnea for three days and was diagnosed as left pneumothorax. After bleb resection, microscopic examination revealed metastatic osteosarcoma forming subpleural fistula and dystrophic calcification. Four years ago, he had had limb salvage operation and chemotherapy for osteosarcoma of left femur. After two and a half years he had a bleb resection for right pneumothorax without any evidence of metastasis. Six months later, he was found to have a 4x3cm sized lung mass in the right lower lobe. After lobectomy, he was diagnosed as pulmonary metastasis of osteosarcoma. Pneumothorax is the common complication of metastatic osteosarcoma to the lung and it may be presented before the pulmonary metastasis is clinically evident. It is important to recognize a pneumothorax of the patients with osteosarcoma as a possible sign of metastases.
Blister ; Chest Pain ; Drug Therapy ; Dyspnea ; Femur ; Fistula ; Humans ; Limb Salvage ; Lung ; Neoplasm Metastasis* ; Osteosarcoma* ; Pneumothorax* ; Sarcoma ; Young Adult

BACKGROUND: A tourniquet is commonly used to achieve a bloodless field in surgery of the extremities. However, the anesthesiologist is concerned about the adverse effects of hypertension which occur during general anesthesia. In this study, we assessed the effects of lidocaine infiltration in the tourniquet site on blood pressure and heart rate during tourniquet inflation under general anesthesia. METHODS: Forty patients of ASA class I or II, scheduled for knee surgery, were randomly divided into two groups. In group 1 underwent general anesthesia and in group 2 also underwent general anesthesia and combined with 1% lidocaine infiltration in the tourniquet site. The changes of systolic and diastolic blood pressure and heart rate were measured before and after toumiquet inflation, after skin incision and 30 min after inflation. RESULTS: Comparing group 1 with group 2, there were significant increases after tourniquet inflation to 30 min after inflation in systolic and diastolic blood pressure in group 1 (p<0.05). However, there were no significant changes in heart rates in either group. CONCLUSIONS: The above results demonstrate that patients who received lidocaine infiltration in the tourniquet site showed less increase in blood pressure during tourniquet inflation.
Anesthesia, General ; Anesthetics ; Blood Pressure* ; Extremities ; Heart Rate* ; Heart* ; Humans ; Hypertension ; Inflation, Economic ; Knee ; Lidocaine* ; Skin ; Tourniquets*

BACKGROUND: Tracheal extubation, as well as intubation, causes hypertension and tachycardia. The aim of this study was to compare the effect of verapamil, lidocaine to lidocaine-verapamil combination in attenuating the cardiovascular changes following tracheal extubation and emergence from anesthesia. METHODS: Eighty patients (ASA physical status 1) were randomly assigned to one of four groups (n=20 each) ; saline (control), 1 mg/kg lidocaine, 0.05 mg/kg verapamil and lidocaine-verapamil combination. These medication were given intravenously 2 min before tracheal extubation. Changes in blood pressure and heart rate were measured following tracheal extubation. RESULTS: Lidocaine, verapamil and their combination all attenuated the changes of heart rate and blood pressure. The inhibitory effect on changes of heart rate and blood pressure were miximum in group of the combination of lidocaine and verapamil. CONCLUSION: We conclude that the verapamil 0.05 mg/kg and lidocaine 1 mg/kg given iv concomitantly 2 min before tracheal extubation is a more effective prophylaxis than verapamil or lidocaine for attenuating the cardiovascular changes associated with tracheal extubation.
Airway Extubation* ; Anesthesia ; Blood Pressure* ; Heart Rate* ; Heart* ; Humans ; Hypertension ; Intubation ; Lidocaine* ; Tachycardia ; Verapamil*

Pneumothorax was recognized as a potential hazard of mechanical ventilation during anesthesia. Because the gases used in anesthesia are delivered from cylinder and wall outlets at higher than atmospheric Pressure, the possibility of damage to the lung is over present. Alveolar rupture may occur when there is free transmission of high pressure to the alveoli during tracheal intubation at the start of anesthesia. We had a case of tension pneumothorax developed during the use of Jackson-Rees modification with Ayres T-piece for primary closure of laceration on right hand in 4 years old child under general anesthesia. The patient was presented of acute respiratory distress resulting from pneumothorax and subcutaneous emphysema just after tracheal intubation. The tension pneumothorax was noticed on chest X-ray. This complication was the result of undesirable alveolar ventilation with high fresh gas flow by accidental using of oxygen flush valve. With the prompt decision of diagnosis of tension pneumothorax and aggresive treatment, the patient recovered uneventfully and discharged 7 days later.
Anesthesia ; Anesthesia, General ; Atmospheric Pressure ; Child ; Child, Preschool ; Diagnosis ; Gases ; Hand ; Humans ; Intubation ; Lacerations ; Lung ; Oxygen ; Pneumothorax* ; Respiration, Artificial ; Rupture ; Subcutaneous Emphysema ; Thorax ; Ventilation

Congentally corrected transposition of the great vessels can best be defined as a malformation in which the aorta and pulmonary artery are transposed in relation to each other but in which the flow of blood is in the physiologic direction. And in addition to the malposition of great vessels, there is an inversion of the ventrice,. Unfortunately this basic malformation seldom exists withot complicating cardiovascular anomalies. We had experienced a case of congenitally corrected transposition of the great vessels associated with itral?insufficiency in 13year-old boy, who presented the most above mentioned findings. We have made diagnosis by cardiac catheterization and selective angiocardiographic study.
Aorta ; Cardiac Catheterization ; Cardiac Catheters ; Diagnosis ; Humans ; Male ; Pulmonary Artery ; Transposition of Great Vessels*

Among patients scheduled for elective thoracic surgery at the Medical Center of Kyung Hee University, 15 patients undergoing lobectomy or pneumonectomy were selected. Three different ventilatory modes were employed and compared to the two-lung ventilation with 50% oxygen (control). First, patients were ventilated with 50% oxygen and left the unventilated lung to deflate during one lung ventilation (test 1). Second, continuous positive airway pressure (CPAP) of 10 cmH2O was applied to the ventilated lung while patients were under one lung ventilation with 50% oxygen (test 2). Lastly, patients were ventilated with 100% oxygen and unventilated lung was left to deflate during one lung ventilation (test 3). PaO2, A-aDO2 and Qsp/QT of three different ventilatory modes were observed and compared to that of control, and that of test 2 to test 1. The results were as followed: 1) Mean PaO2 in test 1 and test 2 were 98+/-24.0 mmHg and 126+/-34.8 mmHg, respectively and were significantly decresed as compared to the PaO2 of control, 234+/-21.4 mmHg. Comparing the PaO2 of test 1 and test 2, there was statistically significant increase in test 2 (P<0.01). 2) Comparing with A-aDO2 of control (68+/-22.5 mmHg), A-aDO2 in both test 1 and test 2 were significantly increased to 210+/-24.3 mmHg and 184+/-33.4 mmHg, respectively. there was significantly decreased in test 2 as compared to test 1 (P<0.01). 3) Shunt percentages (Qsp/QT) were measured as 8.3+/-2.3% in control, 25.4+/- 6.7% in test 1, 19.8+/-3.2% in test 2. Shunt percentages of test 1 and test 2 were increased significantly as compared to the control. Comparing the shunt percentages of test 1 and test 2, there was decreased in test 2 (P<0.01). Based on the above results, the application of appropriate CPAP to the unventilated lung during one lung ventilation is thought to be very effective in preventing hypoxemia. But, vigorous and meticulous monitoring, surveilance of patients and one lung ventilation with 100% oxygen are essential depending on the conditions of ventilated lung and long duration of one lung ventilation.
Anoxia ; Continuous Positive Airway Pressure ; Humans ; Lung* ; One-Lung Ventilation* ; Oxygen* ; Pneumonectomy ; Thoracic Surgery ; Ventilation

PURPOSE: To compare 3D ultrasound (3D-US) with 2D ultrasound (2D-US) in terms of their usefulness and limitations in the diagnosis of breast masses. MATERIALS AND METHODS: We obtained 2D and 3D US images of 37 breast lesions present in 20 cases of fibroadenoma, nine of cancer, and eight of fibrocystic disease proven in a total of 26 cases [fibroadenoma (n=13), breast cancer (n=9), fibrocystic disease (n=4)] by histologic examination, and by clinical evaluation and clinical evaluation with sonographic imaging in eleven. When comparing 3D and 2D-US images we had no prior information regarding detection rate according to the size of lesions, whether or not internal and boundary echo patterns could be interpreted, accurate differentiation between tumorous and non-tumorous lesions, or the accuracy with which benign and malignant tumors could be differentiated. RESULTS: For lesions of 1 cm or less in diameter the detection rate of 3D-US was lower than that of 2D-US, but for lesions over 1 cm there was no difference between the two modalities. In fibroadenoma and breast cancer, 3D-US was more useful than 2D-US for the evaluation of both internal and boundary echo, but with fibrocystic disease and in the diagnosis of tumor/non-tumor, there was no significant difference. In breast cancer, however, 3D-US more accurately determined malignancy, and in fibroadenoma, because of the pseudospicule revealed by 3D-US, this modality was less exact in determining benignancy. CONCLUSION: In the evaluation of internal and boundary echo in breast mass diagnosis, 3D-US was more useful than its 2D counterpart. For lesions of 1 cm or less in diameter, however, the detection rate of 3D-US was low, and since in some benign cases a pseudospicule was apparent, the possibiliy of confusion with malignancy arose. For these reasons, the usefulness of 3D-US was limited.
Breast Neoplasms ; Breast* ; Diagnosis* ; Fibroadenoma ; Ultrasonography