Central venous pressure in humans during short periods of weightlessness.

Central venous pressure (CVP) was measured in 14 males during 23.3 +/- 0.6 s (mean +/- SE) of weightlessness (0.00 +/- 0.05 G) achieved in a Gulfstream-3 jet aircraft performing parabolic flight maneuvers and during either 60 or 120 s of +2 Gz (2.0 +/- 0.1 Gz). CVP was obtained using central venous catheters and strain-gauge pressure transducers. Heart rate (HR) was measured simultaneously in seven of the subjects. Measurements were compared with values obtained inflight at 1 G with the subjects in the supine (+1 Gx) and upright sitting (+1 Gz) positions, respectively. CVP was 2.6 +/- 1.5 mmHg during upright sitting and 5.0 +/- 0.7 mmHg in the supine position. During weightlessness, CVP increased significantly to 6.8 +/- 0.8 mmHg (P less than 0.005 compared with both upright sitting and supine inflight). During +2 Gz, CVP was 2.8 +/- 1.4 mmHg and only significantly lower than CVP during weightlessness (P less than 0.05). HR increased from 65 +/- 7 beats/min at supine and 70 +/- 5 beats/min during upright sitting to 79 +/- 7 beats/min (P less than 0.01 compared with supine) during weightlessness and to 80 +/- 6 beats/min (P less than 0.01 compared with upright sitting and P less than 0.001 compared with supine) during +2 Gz. We conclude that the immediate onset of weightlessness induces a significant increase in CVP, not only compared with the upright sitting position but also compared with the supine position at 1 G.

Heart rate responses to moderate linear body accelerations: clinical implications in aeromedical evacuation.

Linear accelerations during take-off and landing were measured in both civilian and military aircraft usually involved in aeromedical evacuations in Denmark. Accelerations of similar durations and magnitudes were induced in six healthy subjects transported in an ambulance in different supine positions. Heart rate responses recorded depended significantly on the position of the subject. It was concluded that seriously ill patients must be positioned transversely to the axis of acceleration during aeromedical evacuation.

Computer diagnosis in jaundice. Bayes' rule founded on 1002 consecutive cases.

Extensive clinical and clinical chemical information was collected from 1002 consecutive jaundiced patients. Initial selection of variables based on Chi 2-tests or Mann-Whitney U-test allowed the removal of 64 of the 107 variables originally collected. A further selection of variables was carried out using a modified version of Bayes' rule thus reducing the number of variables from 43 to 22. Of the 982 patients with a final diagnosis 743 patients (76%) could be classified correctly into one of 13 diagnostic categories. The Bayes' rule was also applied to a test group of a further 110 jaundiced patients and found to perform equally well: of 108 patients with a final diagnosis 81 (75%) were correctly classified. A comparison between the clinician's diagnosis and the computer-aided diagnosis according to Bayes' rule demonstrated agreement with regard to one of the 13 diagnostic alternatives in 734 patients (75%), of whom 81 patients were wrongly diagnosed. In the test group agreement upon diagnosis was found in 80 patients (74%). By plausibly combining the computer-aided and the clinician's preliminary diagnoses, more correct classifications were obtained than with either method alone. Many diagnostic modalities such as ultrasound examination, CT-scan, and direct cholangiography are at hand today for the differential diagnosis of jaundice. Computer-aided diagnosis using Bayes' rule has proved a reliable tool for the clinician and can be used in the planning of a diagnostic strategy for the individual jaundiced patient.

Postvagotomy diarrhoea and dumping treated with reconstruction of the pylorus.

The results of reconstruction of the pylorus in 12 patients with disabling diarrhoea and/or dumping after vagotomy and pyloroplasty are reported. Eight patients, primarily operated on with a truncal vagotomy and pyloroplasty, all indicated frequent diarrhoea as their principal symptom. After the reconstruction operation the stools were normalized in five, and the frequency of diarrhoea was reduced considerably in two patients. Three of four patients who had had a selective vagotomy and pyloroplasty complained of severe dumping after all kinds of food; after the reconstruction these symptoms were milder and provoked by sweets and milk only. The fourth patient with heavy diarrhoea as the principal symptom had postoperatively a slight reduction of the frequency. The operation is easy to perform, and no complication was encountered. The pathogenesis of the symptoms is discussed, and it is recommended that patients with disabling diarrhoea and/or dumping after vagotomy and pyloroplasty undergo a reconstruction of the pylorus.

Treatment of pathological fractures.

The treatment of 30 patients with 34 pathological fractures is reported. Twenty-six femoral fractures and one ulnar fracture were fixed internally, whereas five fractures of the humerus, one of the radius, and one of the clavicle were treated non-operatively. Twenty-two of the patients were discharged from hospital (21 were mobilized) and eight died in the postoperative period. All patients became free of pain, and bony union occurred in 12 of the fractures. Thirteen per cent of the patients lived less than 1 month whereas 20 per cent lived more than 24 months after fracture. Previously published figures and our results indicate the place of prophylactic nailing of certain femoral metastases, perhaps also in connection with local irradiation of the metastases.

Double-blind randomised clinical trial of a pepsin-inhibitory pentapeptide (pepstatin) in the treatment of duodenal ulcer.

In a double-blind randomised clinical trial a specific inhibition of peptic activity with a pentapeptide, pepstatin, had no significant advantage over placebo in the ulcer healing and symptomatology of duodenal ulcer. Thus, the inhibition of pepsin in human gastric juice does not appear to have a major influence on the healing of duodenal ulcer.

Postoperative pulmonary complications in upper abdominal surgery. A randomized clinical comparison between physiotherapy and blow-bottles.

Blow-bottles were compared with conventional postoperative pulmonary physiotherapy in a randomized trial of 98 patients undergoing gastric or biliary tract surgery. Radiological evidence of postoperative pulmonary lesions found by "blind" evaluation of the films occurred with the same frequency in the two groups (30.6%). Blow-bottles were found preferable to physiotherapy because they are less time-consuming.

Antibody titre changes and skin reactivity in patients with liver cirrhosis undergoing portocaval shunt operation.

Ten patients with liver cirrhosis undergoing portocaval shunt operation have been followed immunologically during their postoperative course regarding antibody titres to various antigens, viral as well as bacterial. The antibody determinations included rubella, vaccinia and cytomagalo viruses, diptheria toxoid, Candida albicans, streptolysin O, typhoid and paratyphoid O and H and the syphilis reactions: Kahn, Wassermann and Meinicke. Twenty-one blood donors served as controls. Skin test reactions to diptheria, Candida albicans, streptokinase and tuberculin were performed on the same patients. Eight patients submitted to cholecystectomy served as controls for pre-and postoperative skin tests and antibody titres. The liver cirrhosis group before operation had a significantly higher number of elevated antibody titres concomitant with a significantly reduced skin test reactivity to diphtheria toxoid and streptokinase. An increase in the number of elevated antibody titres was seen after portocaval shunt operation. In no case was a higher antibody titre associated with an increase in skin reactivity to the corresponding antigen. A number of significant titre changes to viral antigens were seen in the postoperative course without clinical evidence of the corresponding viral disease. Thes findings indicate that under certain circumstances antibody titre changes should be interpreted with caution.