[Pathway of the radial artery located with a small-caliber Doppler probe for arterial cannulation in pediatric patients].

The pathway of the radial artery of 23 patients, ranging in age from 17 days to 10 years, was located with a small-caliber Doppler probe, 1.5 mm in diameter, and the artery was punctured along the pathway traced on the skin surface. In all patients the arterial pathway, including its branch and diameter, was shown clearly. In 11 patients, ranging in weight from 5 to 24 kg, the artery was greater than 0.5 mm in diameter and was cannulated easily. In another 4 patients, all less than 3 kg in weight, the artery under the thin skin layer was cannulated successfully in three of them. However, among the remaining 8 patients, ranging in weight from 3 to 5 kg, cannulation was successful in only two cases. The thick tissue layer, including the skin and the subcutaneous layer over the small artery, was thought to interfere with the accurate location of the artery in the other six patients. Nevertheless, the arterial pathway traced on the skin surface facilitated successful percutaneous cannulation by another method in these six. Visualization of the arterial pathway by the small-caliber Doppler probe was thought to be helpful for percutaneous cannulation, with or without another cannulation method.

Effect of dose of cyclosporine or FK506 and antithrombotic agents on cardiac allograft vascular disease in heterotopically transplanted hearts in rats.

BACKGROUND: We compared the severity of cardiac allograft vascular disease in rats treated with cyclosporine or FK506 and studied the effect of antithrombotic agents on cardiac allograft vascular disease. METHODS: One group each was treated with 2 and 5 mg/kg/day of cyclosporine. Two other groups were injected with heparin and dipyridamole, respectively, in addition to cyclosporine. Four other groups were similarly divided by dose of FK506 (0.1 or 0.25 mg/kg/day) and concomitant anticoagulant treatment. RESULTS: Grade of rejection and percentage stenosis of coronary arteries were lower in groups with high doses of immunosuppressive agents or with heparin. Major histocompatibility class II antigens were expressed by the endothelium of grafted hearts, and IgM and C3 were deposited in the intimal and medial layers in all groups except those administered the higher doses of immunosuppressive drugs. However, no remarkable differences in density of major histocompatibility class II antigens were found between groups demonstrating expression of these antigens. On the other hand, the intensity of IgM or C3 expression grew significantly as coronary stenosis increased in severity. CONCLUSIONS: A significant difference in severity of cardiac allograft vascular disease was not found between the groups treated with cyclosporine and FK506, and cardiac allograft vascular disease was almost entirely suppressed when doses of cyclosporine and FK506 sufficient to suppress graft rejection were administered. Our findings also showed that concomitant heparin administration reduced the extent of allograft rejection and the incidence of cardiac allograft vascular disease.

Trans-septal left atrial catheterisation.

A newly designed 4 FG double-lumen catheter with the second port located either 5 or 7 cm proximal to the tip was tested in five children undergoing open heart surgery. The catheter was inserted percutaneously and initially positioned in the superior vena cava, right atrium or inferior vena cava. During cardiopulmonary bypass, the tip of the catheter was repositioned manually in the left atrium across the interatrial septum. In all patients, left atrial pressure was monitored successfully while central venous pressure was monitored with the second port positioned in the superior vena cava. Removal of the catheter from the left atrium was easily performed and caused no problems.

[A case report of a burn produced by the probe of a pulse oximeter].

We experienced a case of burn produced by the pulse oximeter probe at the finger of a patient. Patient was a 75-year old man scheduled to transurethral prostatectomy. The pulse oximeter probe made by Physio-Control Co. was attached at his finger and was connected to a pulse oximeter manufactured by Ohmeda Co. Soon after the start of Spo2 measurement the anesthetist became aware of abnormal heating of the probe and removed it immediately. But unfortunately a small thermal injury was formed at patient's finger. Abnormally excessive current went through the detector diode and heated the finger probe. Attention to correct connection between the pulse oximeter probe and the finger is necessary before use.

[Effect of midazolam as a premedicant].

A new benzodiazepine-type drug, midazolam, was administered intramuscularly as a premedicant to 155 patients aged from 16 to 81 years with ASA status 1 or 2. The hypnotic action and the effect on the upper airway tract of midazolam were evaluated. Hypnosis appeared 5 minutes after the administration of midazolam, reached its plateau after 20 minutes and started to decline after 30 minutes. The hypnotic effect showed dose-dependent increase in doses ranging from 0.05 to 0.20 mg.kg-1. No age-dependent differences in hypnosis were observed except for teenage group which showed stronger hypnosis than the other age groups. There was no problem on the upper airway tract for all age groups at the dosage of 0.05 mg.kg-1, but in the patients over 40 years increasing dosage tended to obstruct the upper airway tract. Along with the appearance of hypnosis, cough and breath holding, suggesting retention and aspiration of saliva, were observed. The appropriate dosage of midazolam for premedication was considered to be 0.05 mg.kg-1.

[Spinal anesthesia of only one lower extremity with hypobaric tetracaine].

For spinal anesthesia of only one lower extremity, effect factors, assumed to influence the level of anesthesia including the degree of head-down position of the patients during injection, the volume of the drug and the rate of its injection, are studied using 0.2% hypobaric tetracaine solution in water. Seventy-two patients having the surgery of one lower extremity were divided into 7 groups according to the difference in the degree of head-down position (0, 2 and 5 degrees), in the volume (3, 5 and 7 ml) and the rate (0.2, 0.1 and 0.05 ml.s-1) of injection of tetracaine solution. Patients, in lateral position with the operative side up during injection and 20 minutes after injection, were checked for the level of hypesthesia and analgesia on both operative side and non-operative side. Except 2 groups of the patients who were in horizontal position during injection or who are injected with 7 ml of tetracaine solution all at once, the upper level of analgesia in the operative side is well controlled at T10, although in some patients the additional injection of small amount of tetracaine solution was needed. In these patients, the analgesic level in the non-operative side is restricted within S level, and HR and BP changes were very slight. The rate of injection had no effect on the analgesic level on both operative side and non-operative side.