Students' community health service delivery: experiences of involved parties.

For several years the School of Nursing Science and the School of Psychosocial Behavioural Science, of a specific university, have been offering health care services in response to some of the health needs of a disadvantaged community as part of their students' experiential learning. However, these health care services were rendered independently by these two schools, implying that no feedback system existed to evaluate the worth and quality of these student-rendered health care services. The objectives of this research were to explore and describe the experiences of senior nursing and social work students, the experiences of health service delivery organisations concerned and the experiences of the disadvantaged community members receiving such health care services, as well as to investigate which communication models were apparent with regard to the major factors within health communication. An exploratory descriptive qualitative research design was used. Focus group discussions were held, interviews were conducted and field notes taken. Focus group discussions and interviews were transcribed and analysed by the research team to determine themes and sub-themes using the open coding technique. The results of the three groups showed similarities. The health service delivery organisations also identified a communication barrier, although the students were prepared to bridge it. The health service delivery organisations and the community felt positive towards the students and what they offered to the organisations and to the patients. A greater need for multi-disciplinary team work was recognised by al parties concerned. Recommendations focus on improved student accompaniment by lecturers; extending health care delivery to include a multi-disciplinary team approach by students; as well as improving the delivery of health care services.

Hydrocephalus induced chorea.

Chorea can result from many causes, and the diagnostic workup can be challenging. Although often accompanied by other extrapyramidal symptoms, hydrocephalus has not been mentioned as a possible cause of chorea to date. Here we report an unusual case of chorea secondary to normal pressure hydrocephalus, which clearly improved after shunt placement.

Cardiotoxic effects of pavetamine extracted from Pavetta harborii in the rat.

Previous studies have shown that crude extracts from Pavetta harborii as well as dried plant material have cardiotoxic effects on rats and sheep that can lead to heart failure. The active component has since been isolated and identified. This substance has been named pavetamine. The aim of this study was to determine whether pavetamine has cardiotoxic effects similar to those seen in previous reports, when administered to rats intraperitoneally. Sprague Dawley rats received two doses, initially 4 mg/kg and then 3 mg/kg pavetamine respectively and were monitored for 35 days before cardiodynamic parameters were measured by inserting a fluid-filled catheter into the left ventricle via the right carotid artery. These values were compared to those of control rats that had received only saline. Pavetamine significantly reduced systolic function and body mass in the treated rats, which indicates that it has the potential to induce heart failure in this animal model.

The natural course of non-functioning pituitary macroadenomas.

OBJECTIVE: The natural history of non-functioning pituitary macroadenomas (NFMA) has not been completely elucidated. Therefore, we evaluated pituitary function, visual fields, and tumor size during long-term follow-up of non-operated patients with NFMA. DESIGN: Follow-up study. PATIENTS: Twenty-eight patients (age 55 +/- 3 years) with NFMA, not operated after initial diagnosis, were included. RESULTS: Initial presentation was pituitary insufficiency in 44%, visual field defects in 14%, apoplexy in 14%, and chronic headache in 7% of the patients. The duration of follow-up was 85 +/- 13 months. Radiological evidence of tumor growth was observed in 14 out of 28 patients (50%) after duration of follow-up of 118 +/- 24 months. Six patients (21%) were operated, because tumor growth was accompanied by visual field defects. Visual impairments improved in all the cases after transsphenoidal surgery. Spontaneous reduction in tumor volume was observed in eight patients (29%). No independent predictors for increase or decrease in tumor volume could be found by regression analysis. CONCLUSION: Observation alone is a safe alternative for transsphenoidal surgery in selected NFMA patients, without the risk of irreversibly compromising visual function.

An unexpected cause of a recurrent cerebral hemorrhage.

A 4-year-old previously healthy boy presented with a non-traumatic right parietal hemorrhage. A second life-threatening left cerebral hemorrhage occurred three weeks later and was decompressed with a craniotomy. Transthoracic echocardiography revealed a hypermobile elongated tumor of the mitral valve. The cardiac tumor was successfully resected three weeks after the craniotomy. Histological examination of the cardiac tumor revealed a papillary lesion of spindle cells with smooth muscle cell differentiation. In view of the histological findings and the clinical symptoms, a cellular myofibroblastic tumor was considered the most likely diagnosis in our patient. Although a cardiac tumor is a rare cause of a cerebral hemorrhage, a cardiac evaluation is recommended in pediatric patients with a cerebral hemorrhage of unknown etiology.

The role of cromakalim and a nitric oxide synthase blocker in cardiac arrhythmia in the intact baboon model.

The arrhythmogenic effect of adenosine triphosphate (ATP)-sensitive potassium channel openers is controversial and may be dependent on the type of animal model used. Information on the effect of these drugs in the normal primate model is limited. The purpose of this study was first to determine the arrhythmogenic properties of cromakalim in the baboon and second to determine whether N-omega-nitro-L-arginine methyl ester (L-NAME) has any effect on the induced arrhythmia. Adult (2-4 years old) baboons (Papio ursinus) were anesthetized with a continuous i.v. infusion of ketamine (100 mg/ ml), diazepam (5 mg/ml), and saline (ratio 2:2:50) at a rate of 40-60 ml/h. Sympathetic responses were inhibited by administration of propranolol (1 mg/kg) before the start of the experiments. Cromakalim (30 microg/kg) was administered before and after L-NAME (7.5 mg/kg), and the parameters were monitored for 15 min after each intervention. A Millar double-tipped microcatheter was used to record left ventricular and aortic pressures. Lead II of the ECG was monitored. During a 15-min period after administration of cromakalim, 22.3 +/- 6.0 abnormal ventricular complexes were recorded. L-NAME administration significantly reduced these abnormal complexes to 4.5 +/- 2 (paired t test, p < or = 0.05). We therefore conclude that cromakalim has arrhythmogenic properties in the baboon and that these can be attenuated by L-NAME.

Stability of cardiodynamic and some blood parameters in the baboon following intravenous anaesthesia with ketamine and diazepam.

The stability of cardiodynamic and some blood parameters during a slow, continuous infusion of a combination of ketamine and diazepam is reported. Contractility (dP/dt), myocardial relaxation (Tln), left ventricular end-diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP), arterial blood pressure and certain blood parameters were assessed in 3 male and 3 female juvenile baboons (Papio ursinus). Anaesthesia was induced with 15 mg/kg ketamine i.m. and maintained with a continuous i.v. infusion (40-60 ml/h) of ketamine and diazepam. The mixture consisted of 2 ml ketamine (100 mg/ml), 2 ml diazepam (5 mg/ml) and 50 ml saline. A period of 75 +/- 10 min was allowed for preparation of the animals, after which lead II of the ECG, femoral artery blood pressure and left ventricular pressure were recorded at 15-min intervals for a period of 2 h: the total duration of anaesthesia was 195 min. Arterial blood samples were analysed at 30-min intervals for blood gases, electrolytes, glucose and insulin. Left ventricular parameters were derived from the left ventricular pressure curve. Tln, LVSP and LVEDP showed small fluctuations. Contractility decreased (p < 0.037) at the 195-min interval. No arrhythmias or ECG changes were seen, while blood pressure decreased gradually. Serum calcium concentration decreased and blood glucose levels increased gradually over time. Anaesthesia and analgesia were sufficient and no other drugs were necessary. The animals appeared sedated and dazed 60-80 min after the procedure. A continuous infusion of a combination of ketamine and diazepam for a duration of 150 min can provide stable anaesthesia for cardiodynamic measurements.

The low transverse Pfannenstiel incision and the prevalence of incisional hernia and nerve entrapment.

OBJECTIVE: The authors determined the prevalence of incisional hernia and nerve entrapment in patients with a low transverse Pfannenstiel incision. SUMMARY BACKGROUND DATA: The literature on the Pfannenstiel incision suggests an incisional hernia rate of 0.0% to 0.5%. However, in these series, physical examination, which is essential in the authors' view, was not performed. To the authors' knowledge, the prevalence of nerve entrapment after the Pfannenstiel incision is not known or has never been published. METHODS: All adult women, operated on between 1986 and 1992 using a Pfannenstiel incision and not having had another lower abdominal incision other than for laparoscopy, were invited for follow-up at the outpatient department. All patients were interviewed and subjected to a physical examination, with special interest to the presence of incisional hernia or nerve entrapment. RESULTS: In patients having had a Pfannenstiel incision, no incisional hernias were found. In patients also having had a laparoscopy, the incisional hernia rate was 3.5%. Nerve entrapment was found in 3.7%. The length of the incision was identified as a risk factor (p = 0.02). CONCLUSIONS: Incisional hernia is a rare complication of the Pfannenstiel incision. Complications of nerve damage, however, are not uncommon and should be recognized. When possible, nerves should be identified and preserved, especially when extending the incision more laterally.

Some adverse cardiodynamic effects of prostaglandin E2 in congestive heart failure.

The cardiodynamic effects of prostaglandin E(2) (PGE(2)) were studied in both healthy sheep and in animals with congestive heart failure (CHF). Merino ewes were equipped surgically with high fidelity micromanometers and left ventricular pressures measured. Heart rate, left ventricular systolic and end-diastolic pressures, +dP/dt and T(ln) were calculated on a computer from the recorded pressure curves. The paired t-test was used to determine the statistical significance of the differences. PGE(2) (25 mu g/kg) significantly improved the cardiac contractility and relaxation rate of healthy sheep and significantly reduced the heart rate, while the loading conditions under which the heart operates were not significantly affected. In contrast to healthy sheep, PGE(2) significantly reduced the contractility and relaxation rate of sheep with congestive heart failure and significantly increased the preload while heart rate and afterload were significantly reduced. The study suggests that despite the promising vasodilatory, positive inotropic and relaxation rate actions of PGE(2) in normal hearts, PGE(2) might not be a suitable therapeutic agent for CHF, because of the worsening effect it has on the cardiodynamics and loading conditions of the failing heart.

The dose-related hyper-and-hypokalaemic effects of salbutamol and its arrhythmogenic potential.

1. The hypokalaemic effect of salbutamol after more than 30 min of administration has been well described. A hyper-and-hypokalaemic effect for adrenaline has been reported, but no such hyperkalaemic effect for salbutamol. 2. The possible hyper-and-hypokalaemic effects of salbutamol with the concomitant potential for pro-arrhythmia were assessed in the baboon (Papio ursinus). 3. Male and female baboons were anaesthetized with ketamine (15 mg kg-1) and maintained with 6% pentobarbitone as spontaneously breathing animals. Six baboons in each group received either 10, 100 or 500 micrograms kg-1 salbutamol i.v. Lead II of the ECG and femoral i.a. blood pressure were recorded continuously for 10 min. Arterial blood samples were collected at 0 min and then after 3 and 10 min of salbutamol administration. 4. All the animals developed sinus tachycardia (above 200 beats min-1) within 30 s of each dose of salbutamol administration and the high heart rate persisted throughout the experiment. All the animals were hyperkalaemic after 3 min and hypokalaemic after 10 min for each dose of salbutamol. Left ventricular conduction defects were seen in 3 animals during the hyperkalaemic phase. No arrhythmia was seen during the hypokalaemic phase. 5. Salbutamol has a transient hyperkalaemic and a more prolonged hypokalaemic effect in the baboon. The hypokalaemia could not be associated with arrhythmia although conduction defects were associated with the hyperkalaemia. 6. Since salbutamol is used as a bronchodilator in asthmatic patients and to treat acute hyperkalaemia, it is suggested that caution should be exercised when using salbutamol in high doses to treat acute asthma especially during the first few minutes of administration. The finding of hyperkalaemia with salbutamol questions its use in the treatment of hyperkalaemia.

Cardiodynamic improvement following PGE1 administration in sheep with congestive heart failure.

The cardiodynamic effects of Prostaglandin E1 were studied in sheep with congestive heart failure. Six Merino ewes were equipped surgically with high fidelity micromanometers and left ventricular pressures measured. Heart rate, left ventricular systolic and end-diastolic pressures, [+dP/dt]max and a single-exponential time constant (T) were calculated on a computer from the recorded pressure curves and the Wilcoxon signed rank test used to determine the statistical significance of the differences. Prostaglandin E1 (20 micrograms.kg-1) significantly improved left ventricular contractility and relaxation rate as seen respectively from [+dP/dt]max and the single-exponential time-constant and reduced the afterload conditions under which the heart operated, during various stages of congestive heat failure, without significant tachycardia during the more advanced stages of the disease. The results show that [+dP/dt]max increased between 16% (stage 4) and 38% (stage 1); T shortened between 14% (stage 4) and 25% (stage 1) and left ventricular systolic pressure decreased between 14% (stage 4) and 21% (stage 1) when prostaglandin E1 was administered during four stages of left ventricular pump failure, which ranged from a 20% decrease in [+dP/dt]max (congestive heart failure stage 1) to a 50% decrease in [+dP/dt]max (congestive heart failure stage 4). In contrast to normal animals, prostaglandin E1 caused an increase in left ventricular end-diastolic pressure during the more advanced stages of pump failure. Nevertheless the favourable cardiodynamic changes brought about by prostaglandin E1 administration might contribute, together with afterload reduction, to a general haemodynamic improvement during congestive heart failure.

Evidence of direct positive inotropic and chronotropic actions by PGE1 not mediated by cyclic AMP in conscious sheep.

The underlying mechanism for the cardiac responses to PGE1 has not yet been fully elucidated. In order to investigate a possible role for cyclic AMP in the positive inotropic and chronotropic actions of prostaglandin E1 (PGE1) in conscious sheep, theophylline-ethylenediamine was used to inhibit phosphodiesterase activity. Any significant potentiation or the lack of potentiation of the measured cardiac response to PGE1 was then used as a criterion to establish whether the cardiac actions of PGE1 were produced by an alteration in the intracellular levels of cyclic AMP. The results suggest that PGE1 produced positive inotropic and chronotropic actions in conscious sheep, which is neither caused by the autonomic nervous system (baroreflexes) nor by changes in intracellular cyclic AMP levels. Further research seems warranted to establish whether a relationship exists between Ca2+ and the contractile response of PGE1. Such a relationship could then possibly explain the positive inotropic action of PGE1 in conscious sheep.

Compilation of regression equations employing the RR interval for the correction of systolic time interval measurements for heart rate in sheep.

The aim of this study was to determine the validity of regression equations relating RR interval and heart rate to systolic time intervals in sheep. Regression equations were compiled employing the RR interval to correct systolic time intervals for heart rate in six Merino ewes. A range of heart rates was obtained by means of pharmacological intervention as well as electrical pacing. Heart rate did not affect the pre-ejection period, isovolumetric contraction time, the pre-ejection period to left ventricular ejection time ratio, the ratio QS2/QT, electrical delay (Q1), or the PR interval. Heart rate did, however, affect the duration of electromechanical systole (QS2), left ventricular ejection time and mechanical systole (S1S2). The study showed that it was preferable to correct the systolic time intervals using the RR interval rather than the heart rate. Bazett's equation to correct electrical systole (QT) for heart rate in humans was also validated in sheep.