Tracheal constriction by morphine and by fentanyl in man

The effects of morphine and fentanyl on tracheal smooth muscle tone were studied in 38 patients during induction of anesthesia. Endotracheal tube cuff pressure was used to measure tracheal tone. Anesthesia was maintained with nitrous oxide, 70 per cent in oxygen, and pancuronium and ventilation was controlled with a respirator. Morphine, 0.5 mg/kg, produced a biphasic response, initially causing tracheal dilatation and then tracheal constriction. Ten minutes after morphine injection, cuff pressure increased to significantly (21 +/- 8 per cent) above control. Morphine-induced tracheal constriction could be completely blocked by the prior administration of atropine, 0.5 mg. Fentanyl, 0.006 mg/kg, also produced significant tracheal constriction, cuff pressures increasing to 44 +/- 11 per cent above control at 10 min. Fentanyl-induced tracheal constriction could be blocked by pretreatment with droperidol, 0.25 mg/kg. At equianalgesic doses, morphine and fentanyl produced similar tracheal constriction.     

Lower extremity lengthening by Wagner's method and by callus distraction

Fifty-three patients underwent 64 lengthenings of the femur or tibia by the Wagner technique or by the callus distraction method. Thirty-six femoral and 28 tibial segments were lengthened. Simultaneous lengthening of the femur and tibia was performed in seven limbs. Three segments underwent repeat lengthenings. The average length gained by the Wagner method was 5.1 cm in the femur and 5.4 cm in the tibia. Length gains by callus distraction were 4.9 cm in the femur and 4.5 cm in the tibia. Complication rates were fewer and less severe with callus distraction. The number of operations, days of hospitalization, and length of total treatment were less in patients operated on with the callus distraction method than in those who underwent the Wagner technique.     

Tarsal tunnel syndrome caused by synovial cysts and by neurilemmoma

Summary The tarsal tunnel syndrome is the least frequent nerve entrapment of the peripheral nerves. Its etiology is varied and sometimes difficult to determine. The anamnestic data are very important in the initial diagnosis. Clinical data should always be supported by electromyography. We report two typical cases caused by synovial cysts and neurilemmoma. In these case histories we think it necessary to perform MRI as it gives valuable information on the morphology that the surgeon will have to deal with and provides visual confirmation of the diagnosis. Analyzing the results, we specified the constant need for a routine prevention of cicatricial fibrosis.     

Enhancement by hyponatremia and hyperkalemia of ventricular conduction and rhythm disorders caused by bupivacaine

Intraventricular conduction disorders and reentrant arrhythmias in dogs can be produced by high plasma bupivacaine concentrations. The authors' aim was to determine if these conduction disturbances also occurred at moderate plasma bupivacaine concentrations (2.2-3.7 micrograms/ml) when in association with other factors which affect intracardiac conduction, such as hyponatremia and hyperkalemia. Thus, duration of the QRS complex, ventricular conduction time, and effective refractory period (ERP) was measured during ventricular pacing at 180 beats per min in 46 anesthetized, closed-chest dogs separated into five treatment groups as follows: group I, an iv bolus of 4 mg/kg of bupivacaine plus an infusion of 0.1 mg.kg-1.min-1 of bupivacaine followed in 50-60 min by 10 ml.kg-1.min-1 of 1.5% glycine iv to produce dilutional hyponatremia; group II, 1.5% glycine alone, as above; group III, bupivacaine, as above, followed in 50-60 min by 0.05 mmol.kg-1.min-1 of KCl iv to produce hyperkalemia; group IV, KCl alone, as above; and group V, bupivacaine, as above, except that the duration of infusion was 90 min. QRS duration and ventricular conduction time, which were prolonged approximately 33% and 61%, respectively, by bupivacaine alone were additionally prolonged 29% and 44%, respectively, when serum sodium concentration was lowered to 114 mmol/l and potassium concentration was raised to 7.7 mmol/l. The combinations of bupivacaine and hyponatremia, and bupivacaine and hyperkalemia tended to increase ERP more than did bupivacaine alone, although these changes were not statistically significant. Wave burst arrhythmias and episodes of ventricular tachycardia occurred spontaneously or were triggered by pacing in those dogs in which conduction time was most prolonged.(ABSTRACT TRUNCATED AT 250 WORDS)     

电化学发光法测定HBV标志物与荧光定量PCR-HBV-DNA结果的分析比较

目的探讨HBV标志物与HBV-DNA的相关性,更加准确地了解患者HBV感染、病毒复制和传染性情况,为临床制定合理的治疗方案、疗效观察和预后评估提供依据。方法用电化学发光法测定HBV标志物,用实时荧光定量PCR方法检测HBV-DNA。结果 HBV标志物模式1～5均有HBV-DNA阳性检出,其中模式4的检出率最高（81.7%）,而且DNA含量也最高;模式6～9均为DNA阴性。在乙肝五项指标中,HBeAg的定量结果与HBV-DNA含量相关性最大（r=0.713）。结论 HBV标志物和HBV-DNA既相关又有所不同,应将两者结合起来并相互补充才能更好的反映患者HBV病毒复制和传染性情况。     

Myocardial depression by nitrous oxide and its reversal by Ca++.

The effects of 50 per cent nitrous oxide on isometric contractile force of electrically stimulated cat papillary muscle suspended in a Tris-buffered solution at five concentrations of Ca++ ranging from 1 to 15 mM were studied. Compared with an equal concentration of nitrogen, or with pure oxygen, nitrous oxide caused a highly significant reduction in contractile force, averaging 22 per cent at 2.5 mM Ca++. This reduction in force, like that caused by halothane, could be antagonized by increasing [Ca++] in the bathing medium. However, the reductions in force caused by equinarcotic concentrations of halothane and nitrous oxide are significantly different in magnitude, suggesting that the mechanisms of anesthetic action in the central nervous system and in the myocardium may not be the same.     

Acceptance of preoxygenation in clinical routine by patients and by anaesthesiologists

Preoxygenation is a simple technique to expand the time under planned apnea till the patient is endangered by hypoxia. In this study, we analysed how preoxygenation is used by anaesthesiologists in clinical routine and how this method is tolerated by the patients. One hundred and twenty-one anaesthesiologists of 4 hospitals were interviewed anonymously about training level, rank, indication for preoxygenation and techniques of preoxygenation, as well as their estimation of the patients' discomfort during preoxygenation. Data on 100 patients about oxygen-mask-tolerance were acquired by an anonymous questionnaire from a standard quality control inquiry. We received back 76 of the 121 questionnaires of anaesthesiologists (63 %). Fifty-nine percent of the anaesthesiologists (45/76) preoxygenated in clinical routine. With increasing training time and higher ranks, less anaesthesiologists preoxygenated routinely: junior residents: 80 %; senior residents: 68 %; consultants: 60 %; assistant medical directors: 48 %.80 % of the anaesthesiologists (61/76) used imperfect techniques for preoxygenation (e. g. oxygen-flow < 8 l/min). At the time of preoperative evaluation, the patients estimated the discomfort during preoxygenation on a continuous scale (1 to 10) as 2 (median; 1 - 7: 95 % confidence interval). Postoperatively, the patients mentioned no discomfort: 1 (1 - 1). The anaesthesiologists overestimated their patients' discomfort significantly with 5 (3 - 7) (p < 0.001).In conclusion, preoxygenation, a simple safety procedure, is not routinely used by many anaesthesiologists and imperfect methods are often employed. A possible reason for the anaesthesiologists' reluctance to preoxygenate is an overestimation of the patients' discomfort, though the patients tolerate preoxygenation very well.     

Interleukin-6 is produced by bone and modulated by parathyroid hormone

Interleukin-6 (IL-6) is a cellular regulatory molecule, the diverse functions of which relate to cells both within and outside the immune system. In this report we demonstrated that bone tissue, specifically osteoblasts, produce interleukin-6 and that this function can be modulated by the osteotrophic hormone parathyroid hormone (PTH). Given that the complex process of bone remodeling is now thought to be regulated not only by systemic hormones but also by locally produced factors, the existence of a parathyroid hormone-stimulated production of interleukin-6 by osteoblasts may have important physiological significance.     

Urea excretion in white rats and kangaroo rats as influenced by excitement and by diet

Reprinted from The American Journal of Physiology, Vol. 181, No.1, April, 1955.