Physical activity school intervention: context matters.

School-based interventions for increasing physical activity among children are widespread, however there is still a lack of knowledge about how school context factors are linked to implementation quality and effectiveness of programmes. The aim of this paper is to examine teacher-perceived effectiveness of a Danish national classroom-based health programme 'Active Around Denmark' and in particular, to investigate whether perceptions vary as a function of school social context factors. After completion of the programme all teachers (N = 5.892) received an electronic questionnaire. 2.097 completed the questionnaire (response rate 36%) and 1.781 datasets could be used for analysis. The teachers were asked about their perceptions of changes in children's attitudes towards and levels of physical activity after the competition. Our results indicated that certain contextual factors, such as schools' prioritization of health promotion, teachers' support by their school principal in implementation as well as teacher's satisfaction with the school' physical environment made a significant difference in teacher-perceived effectiveness. To conclude, teacher-perceived effectiveness of the health programme does vary as a function of school social context factors.

Estimation of pulmonary diffusion resistance and shunt in an oxygen status model.

A compartment model of the transport of oxygen from the alveoli to the tissues is described. In patients with both pulmonary shunt and alveolar resistance to diffusion of oxygen, the model is used to simulate their response to variations in the inspired oxygen fraction. These simulation results are compared to the responses from a patient with respiratory malfunction, indicating that the method can identify patients where not only a pulmonary shunt but also a high alveolar resistance to diffusion of oxygen is clinically significant. Estimation of pulmonary shunt and oxygen diffusion resistance can be done in two different implementations of the model. In the first implementation the estimates are generated by numerical solution of the equations of the compartment model. In the second implementation the equations have been used to construct a causal probabilistic net where biological uncertainties and uncertainties in the measurements can be represented.

Postoperative hypophosphataemia and muscle function.

Muscle function tests of the triceps brachii muscle were performed before operation and on the third postoperative day in ten patients undergoing elective cholecystectomy. Electromyograms (EMGs) were recorded by surface electrodes during sustained isotonic and isometric muscle contraction with a constant force of 20 per cent of the preoperative maximal voluntary contraction. Root-mean-square of the EMG was calculated together with the neuromuscular efficiency and measures of the fatiguability. These parameters were compared with changes in the simultaneously measured serum phosphate concentrations. Mean (s.e.m.) neuromuscular efficiency measured after 32-40 s of muscle contraction decreased 14(5) per cent after operation (P less than 0.01), whereas the mean fatiguability of the muscle was unchanged. Mean serum phosphate concentration was 0.87(0.06) mmol/l before operation and 0.79(0.06) mmol/l 3 days after the operation (P greater than 0.05). Two patients developed severe postoperative hypophosphataemia (serum phosphate concentration less than 0.50 mmol/l). Postoperative muscle function deterioration was not associated with changes in the serum phosphate level (P greater than 0.10; r = 0.03). We conclude that patients undergoing cholecystectomy develop postoperative deterioration in skeletal muscle function, which is not associated with serum phosphate concentration.

Serum creatine kinase-B activity in patients with chronic lower-limb ischemia and after leg amputation.

Serum creatine kinase-B (CK-B) activity was measured and electrocardiograms (ECG) recorded before and after operation in two groups of ten orthopedic patients. Group I underwent lower-limb amputation because of severe, chronic ischemia of the leg and group II (controls) had knee prosthesis implantation or knee ligament surgery. In group I the number of patients with CK-B activities exceeding the discrimination value (0.25 muka-tal/l) for acute myocardial infarction preoperatively and 2, 24, 48, 72 hours, and at 7 days postoperatively were, respectively, three, three, five, three, two and nil. In Group II the serum CK-B activity remained below the myocardial infarction discrimination value in all patients at all times. No ECG abnormalities indicating myocardial infarction appeared in any patient of either group. The study indicates that severe, chronic lower-limb ischemia and amputation of the leg may cause elevation of non-cardiac CK-B activity in serum that can interfere with enzymatic recognition of acute myocardial infarction.

Serum and urinary phosphate during and after prolonged muscular ischaemia in non-exercising men and women.

Serum inorganic phosphate (Pi) concentrations and urinary Pi excretions were measured in nine patients undergoing abdominal aortic bypass grafting (group I) and in nine patients undergoing lower limb arterial embolectomy (group II). In group I, serum Pi concentrations were normal until 24 h after reperfusion, when they decreased, reaching their nadir at 48 h (median Pi 0.45 mmol 1(-1). The urinary phosphate clearance relative to the creatinine clearance (Cp/Cc) increased 5 min after reperfusion reaching a maximal median value (0.454) in the 2-24-h collection period. In group II, eight patients had a normal and one had a subnormal serum Pi before reperfusion. None developed hypo- or hyperphosphataemia and the Cp/Cc remained unchanged. Daily urinary Pi excretion was higher in group I than in group II (P less than 0.03). The authors concluded that the regional muscular ischaemia in non-exercising men and women was not associated with hyperphosphataemia. The possible influence of major surgery and anaesthesia on phosphate homeostasis should be considered.

Complement and leukocyte changes during major vascular surgery.

To gain further insight into the effects of major vascular surgery involving the abdominal aorta on complement and leukocytes, serial measurements of leukocyte and differential counts, plasma concentrations of C3d, and granulocyte elastase bound to alpha1 proteinase inhibitor (E-alpha1PI) were made after aorta declamping in a group of patients not receiving blood or plasma. In the hours after declamping, lymphocyte count decreased, whereas an increase was noticed in leukocytes, neutrophils, and plasma E-alpha1PI. Complement activation was not found. Previous reports on complement activation during aortic surgery probably reflect the administration of blood and plasma during the surgical procedures. Whether aortic cross-clamping or interaction between granulocytes and the aortic prothesis is responsible for the release of lysosomal enzymes during the procedure warrants further studies.

Non-cardiac creatine kinase-B activity in serum after abdominal aortic bypass surgery.

Serum creatine kinase (CK) and creatine kinase isoenzyme MB (CK-B) were measured and electrocardiogram (ECG) recorded preoperatively and 24, 48 and 72 hours and 7 days after abdominal aortic bypass grafting in ten patients. No ECG abnormality indicating acute myocardial infarction (AMI) appeared and no patient had chest pain. CK-B was below the discrimination value for AMI in all cases preoperatively, but increased significantly after the operation to a maximal median value of 15 (range 5-32) U/l at 48 hours. The time-activity curve of CK paralleled that of CK-B, reaching a maximal median value of 814 (range 289-1972) U/l at 48 hours. On day 7 CK and CK-B had normalized. The CK-B activity relative to CK activity remained below 6% in all patients. Elevated serum CK-B activity should be utilized with caution for the diagnosis of perioperative AMI in patients undergoing aortic bypass grafting.

Rhabdomyolysis and acute renal failure following an overdose of doxepine and nitrazepam.

A 50-year-old woman developed rhabdomyolysis and myoglobinuric renal impairment after an oral dose of 250 mg nitrazepam and 1,250 mg doxepin. Serum creatinine increased from 70 mumol/l to 472 mumol/l in two days. Serum creatine phosphokinase reached a maximal level of 391 mu kat/l (reference range less than 2.5 mu kat/l) on the third day and serum myoglobin was maximally 910 nmol/l (reference range less than 4.5 nmol/l) on the fourth day after the overdose. Passive and active movements of the knees and ankles became increasingly restricted, but the patient felt no muscle pain. Diuresis decreased to 20-22 ml/hour in spite of repetitive doses of furosemide, but was enforced to greater than 100 ml/hour by vigorous infusion of saline. Haemodialysis was avoided on this regimen. It is suggested that in patients intoxicated with nitrazepam and/or doxepin, rhabdomyolysis should be suspected when a rapidly increasing serum concentration of creatinine is found, even in the absence of muscle pain.

Delayed hypercalcemia after non-oliguric acute renal failure associated with rhabdomyolysis.

Alterations in the calcium metabolism are a characteristic paraclinical finding in patients with oliguric acute renal failure associated with rhabdomyolysis. A 20-year-old male operated on under general anesthesia developed non-oliguric acute renal failure due to malignant hyperthermia with rhabdomyolysis (urine myoglobin greater than 20,000 nmol/l; reference range less than 0.85 nmol/l). On the 20th postoperative day hypercalcemia was found, reaching a maximum serum level of 3.74 mmol/l (reference range 2.18-2.65 mmol/l) on the 27th postoperative day. Delayed hypercalcemia in non-oliguric acute renal failure associated with rhabdomyolysis has not been reported previously. This case suggests that prolonged control of the serum calcium level should be performed in patients with rhabdomyolysis, even in the absence of oliguria.

Lower limb transcutaneous oxygen tension during aortic bypass grafting.

Transcutaneous oxygen tension (tcPO2) was measured continuously at the foot of 10 patients during abdominal aortic bypass grafting. Median tcPO2 before surgery was 38.5 mmHg (range: 14-74 mmHg) increasing to 79.0 mmHg (range 44-104 mmHg) after insertion of the vascular prosthesis (p less than 0.01). Eight successful vascular reconstructions were correctly identified intraoperatively. One was correctly identified as failed and one was correctly identified as unchanged compared with the preoperative clinical status. Our results indicate that tcPO2-monitoring may contribute to quality assurance by intraoperative identification of failed or insufficient vascular reconstructions.

[Effects of induction and supplementary doses of atracurium. Dose-response relationship, spontaneous reversion period, cardiovascular effect and clinical signs of histamine liberation]. / Wirkung der Induktions- und Ergänzungsdosen von Atracurium. Dosis/Response-Verhältnis, spontane Reversionszeit, kardiovaskuläre Effekte und klinische Zeichen einer Histaminfreisetzung.

The effects of an induction dose of atracurium 0.6 mg/kg and supplementary doses of 0.2 mg/kg and 0.1 mg/kg were investigated in 20 patients undergoing non-urgent laparotomy while anesthetized with halothane-N2O-O2. Atracurium was the only muscle relaxant used. Complete neuromuscular block was achieved in all patients, lasting an average of 37 min. Following a supplementary dose of 0.2 mg/kg or 0.1 mg/kg the neuromuscular block was extended on average for a further 25 min (range 13-37 min) or 15 min (range 5-30 min), respectively. The time to spontaneous reversion of complete neuromuscular block at TOF = 0.75 was 39 min (mean). Neither blood pressure nor pulse rate changed significantly following injection of the induction dose. In 3 patients (15%) there was a brief period of erythema with no simultaneous change in pulse rate or blood pressure after administration of the induction dose. The erythema did not recur in the same patients following the supplementary doses. Transitory rises in AST and LDH were noted in 1 patient.

Severe hypophosphatemia following elective abdominal aortic bypass grafting.

Serum phosphate levels and urinary phosphate excretion were investigated in ten patients undergoing elective abdominal aortic bypass grafting. The abdominal aorta was cross-clamped peroperatively for 50-95 min. The median serum phosphate was within reference range (0.80-1.55 mmol/l) during cross-clamping and for the first 24 hours after revascularization of the lower limbs. At 48 hours there was statistically significant fall in the serum phosphate level in all patients, with median reaching a nadir of 0.49 mmol/l. At 72 hours this level had risen to 0.69 mmol/l, and reference range had been regained 7 days postoperatively. The median urinary phosphate excretion (mmol) was 38.4 during the first 24 postoperative hours, and 34.7 and 10.0 on the 2 subsequent days. The median ratio of urinary phosphate to creatinine clearance was, respectively, 0.47, 0.37, 0.09 and 0.08 on postoperative days 1, 2, 3 and 7. The study indicated that patients undergoing aortic bypass grafting with protracted regional muscular ischemia may constitute a risk group with respect to development of severe postoperative hypophosphatemia.

Hypermyoglobinemia after successful arterial embolectomy.

Myoglobin concentrations in serum and urine were measured in eight patients who underwent successful arterial embolectomy in the femoral or iliac arteries. Median serum myoglobin levels significantly increased after revascularization to a maximum of 4741 micrograms/L (reference range: 0 to 80 micrograms/L) 2 hours postoperatively, with a concomitant and correlated increase in the urine myoglobin concentration. Three days after the operation, serum myoglobin concentrations were still substantially elevated in three patients. None of our patients suffered permanent renal damage, but transient renal impairment was noted in five patients, as evaluated from the serum and urine beta 2-microglobulin concentrations. We found an association between the concentrations of myoglobin in serum and urine (Spearman's rho: 0.66; p less than 0.001) and between the concentrations of myoglobin in urine and beta 2-microglobulin in urine (Spearman's rho: 0.65; p less than 0.001). Our results indicate a transient renal impairment associated with hypermyoglobinemia and myoglobinuria, even after successful arterial embolectomy.

Neuroleptic malignant syndrome during perphenazine treatment.

A 50-year old woman developed symptoms of a neuroleptic malignant syndrome with myoglobinuric renal failure during treatment with perphenazine. After discontinuation of perphenazine and repetitive haemodialysis, the patient recovered. Clinical characteristics of the syndrome, differential diagnosis and various therapeutic possibilities are shortly reviewed.