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Haemodynamic responses to nicardipine in humans anaesthetised with halothane.

The haemodynamic effects of an infusion of nicardipine were studied noninvasively before, during and after halothane anaesthesia in man, using a simple technique to achieve constant plasma drug concentrations. Eighty patients were randomly allocated to receive an intravenous infusion of either nicardipine or normal saline. Systolic and diastolic arterial pressures were significantly lower and heart rate significantly higher throughout the infusion than before infusion (p less than 0.001, all variables) in those patients who received nicardipine. The hypotension induced by nicardipine was not affected by induction of anaesthesia; halothane significantly reduced the nicardipine-induced tachycardia (p less than 0.001). Nicardipine caused no cardiac rhythm disorders. This technique for the intravenous administration of nicardipine achieves appropriate stable plasma concentrations, is devoid of severe haemodynamic disturbance and appears to be safe to use during halothane anaesthesia in patients with normal left ventricular function.

Adolescent↗

A randomized control trial of a vegetarian diet in the treatment of mild hypertension.

The effect of an ovo-lacto-vegetarian (OLV) diet on blood pressure was assessed in a randomized, controlled, crossover trial in 58 mild untreated hypertensive subjects recruited from the Perth Centre for the 1983 NHF Risk Factor Prevalence Survey. Subjects were randomly allocated to one of three groups; the first maintained their usual diet throughout 12 weeks; the other two were given an OLV diet for either the first or second 6 weeks of the 12-week trial. Introduction of an OLV diet was associated with a significant fall in systolic blood pressure, on average of the order of 5 mmHg, which was unrelated to change in urinary sodium, potassium or body weight. It was concluded that a vegetarian diet may have an adjunctive role in control of mild hypertension, but that in view of likely problems with acceptability those dietary components responsible for the blood pressure differences need to be identified.

Adult↗

Preinduction atropine or glycopyrrolate and hemodynamic changes associated with induction and maintenance of anesthesia with propofol and alfentanil.

Total intravenous anesthesia by infusions of propofol and alfentanil may be associated with decreases in heart rate and blood pressure. The effects of two vagolytic agents on these hemodynamic changes were studied in 24 ASA physical status 1 patients undergoing body surface surgery. Patients were randomly allocated to receive atropine 10 micrograms/kg, glycopyrrolate, 5 micrograms/kg, or 0.9% sodium chloride, intravenously, 5 min before induction of anesthesia with loading doses of alfentanil, 50 micrograms/kg and propofol 1 mg/kg. Anesthesia was maintained with infusions of alfentanil 50 micrograms.kg-1.hr-1, and propofol 10 mg.kg-1.hr-1 for the first 10 min, 8 mg.kg-1.hr-1 for the next 10 min, and 6 mg.kg-1.hr-1 thereafter. Patients given glycopyrrolate before anesthesia had significantly higher arterial pressures than did patients receiving either atropine or saline, even though heart rates increased equally after glycopyrrolate and atropine.

Adult↗

A randomized trial of librarian educational participation in clinical settings.

In order to evaluate the librarian's educational role in patient care settings, an information service was provided for health professionals, patients, and families by two part-time clinical librarians. Eight clinical areas were randomly selected from a pool of settings which met predetermined entry criteria. Four of these settings were randomly allocated to the experimental maneuver (that is, the clinical librarian service), and four were control settings. Results showed that the clinical librarians were accepted by health professionals and that services to all groups were viewed as successful. Significant differences in information-seeking patterns were found between study and control groups of health professionals. In particular, the study group was more likely to use the library for direct patient care and rated the librarian and library resources more highly as sources of information. This time-limited and education-oriented model would be useful for settings in which a full-time librarian program is not feasible.

Attitude↗

Intravenous sedation for ocular surgery under local anaesthesia.

Anterior segment ophthalmic surgery is commonly performed under local anaesthesia. In order to improve patient comfort, a variety of sedation techniques has been employed in the past. The object of this study was, firstly, to determine whether continuous intravenous sedation during surgery offered any advantages in patients premedicated with temazepam and metoclopramide, and, secondly, to compare midazolam to propofol for this purpose. Forty nine patients were randomly allocated to receive no intravenous sedation (n = 15), continuous propofol infusion (n = 17), or continuous intravenous midazolam infusion (n = 17) after peribulbar anaesthesia. Each technique provided cardiovascular and respiratory stability and allowed early recovery with minimal postoperative sequelae. Unexpected ocular field movement occurred more commonly in the patients receiving intravenous sedation, although statistical significance was not shown (p = 0.06). Significantly more patients in the intravenous sedation groups reported amnesia (p = 0.03). Patient acceptability was good irrespective of the technique used. This study suggests that continuous sedation using propofol or midazolam is not beneficial and should be avoided in ophthalmic patients who have received a simple premedication.

Aged↗

Colloid versus crystalloid cardioplegia. A prospective, randomized clinical study.

The effects of adding colloid (dextran 40, Rheomacrodex) to cardioplegic solution were studied in 55 men undergoing bypass grafting for uncomplicated coronary artery disease. The patients were randomly allocated to group I (n = 27), in which 35 g dextran 40 was added to the St Thomas II cardioplegic solution, or group II (n = 28), which received a standard crystalloid cardioplegic solution. The groups were comparable in regard to preoperative and intraoperative data. In group I the pulmonary vascular resistance index was transiently elevated after extracorporeal circulation and both oxygen consumption and arteriovenous oxygen content difference 2 hours postoperatively were greater than in group II, suggesting better microcirculation. Postoperative normalization of the chest X-rays was more rapid in group I. The clinical course was similar in the two groups.

Cardioplegic Solutions↗

Preoperative external biliary drainage in obstructive jaundice. A prospective controlled clinical trial.

57 patients with obstructive jaundice were randomly allocated to surgery with preoperative external biliary drainage (29 patients) and without preoperative external biliary drainage (28 patients). 22 patients ultimately underwent laparotomy after a mean of 11.7 days of drainage and 25 had surgery without preoperative drainage. The postoperative complication rate was low and similar in both groups but complications associated with the drainage procedure were substantial. Perioperative mortality was 4/28 (14%) in the drainage group and 4/27 (15%) in the non-drainage group. There seems to be no advantage associated with routine preoperative external biliary drainage before surgery for obstructive jaundice.

Acute Kidney Injury↗

Chronic non-asthmatic cough is not affected by inhaled beclomethasone dipropionate. A controlled double blind clinical trial.

Thirty-one patients with a dry cough for at least 1 h duration in more than half of the last 30 days and with no recent respiratory infection participated in a clinical trial to evaluate the effect of inhaled beclomethasone dipropionate (BDP). Lung function was normal and reversibility was excluded by spirometry before and after bronchodilator and by no diurnal variation in home peak flow monitoring. Only one had significant eosinophilia and only three were mildly hyperreactive by bronchial provocation with histamine. After a 1-week run-in period the patients were randomly allocated to receive either BDP 4 puffs of 50 micrograms b.i.d., or placebo. After 2 weeks the patients were crossed over and received the alternative treatment for another 2-week period. The degree of cough, disturbance of night sleep and peak expiratory flow morning and evening were recorded daily in a diary. Spirometry was performed at each control visit. A significant period effect from run-in to period 1 and/or from period 1 to period 2 was demonstrated for cough and disturbance at night but not for peak flow or spirometry. However, no significant treatment effect was found for any of the measured variables.

Administration, Inhalation↗

Does timing of hemodilution influence the stress response and overall outcome?

This study was designed to assess the stress response of acute hemodilution (AH) in patients subjected to radical cystectomy. Forty adult male patients were randomly allocated into a control group (n = 10) where homologous blood transfusion was used, a preinduction AH group (n = 20) where AH was performed before lumbar epidural block and induction of anesthesia, and into a postinduction group (n = 10) where AH was performed after induction of anesthesia. Monitored variables included hemodynamic, hematological and coagulation factors, liver function tests, and serum hormones. AH performed in awake or in anesthetized patients did not result in significant hemodynamic disruption, or result in detectable end-organ or stress-hormone changes when compared to control patient outcomes after radical cystectomy. Hemodilution can be performed by protocol for patients who are undergoing this procedure without major adverse effects.

Adult↗

Randomised, controlled trial of squatting in the second stage of labour.

A new obstetric aid, the 'Birth Cushion' allows the parturient to sink into a supported squatting posture for the second stage of labour and delivery; it fits onto conventional delivery beds. A prospective, controlled trial of 427 primiparae compared the outcome of labour in women randomly allocated to squatting (218) or conventional semirecumbent (209) management. The squatting group had significantly fewer forceps deliveries (9% vs 16%) and significantly shorter second stages (median length of pushing 31 vs 45 min) than the semirecumbent group. There were fewer perineal tears, but more labial tears, in the squatting group. Apgar scores, blood loss, and post-partum vulvar oedema were similar in both groups. 82% of the women in the squatting group maintained upright positions for most of the second stage, and reported great satisfaction with the supported squatting position. The traditional birth posture of squatting can be easily adapted for modern labour management and has advantages for women in their first labour.

Adult↗

Is aspiration of middle ear effusions prior to ventilation tube insertion really necessary?

A prospective double blind randomized trial of 55 children undergoing myringotomy and insertion of ventilation tubes for bilateral middle ear effusions was undertaken. The aim of the study was to assess the need for clearance of the middle ear by aspiration prior to the insertion of ventilation tubes. The day before surgery the children were assessed by clinical examination, pure tone audiometry and impedance audiometry. At the time of surgery each child underwent bilateral myringotomy, with aspiration of the right or left ear only on a randomly allocated basis. Standard ventilation tubes were then inserted. Postoperative evaluation up to three months following surgery showed no significant differences between the aspirated and the non-aspirated middle ears. We conclude that routine evacuation of the middle ear prior to ventilation tube insertion is not necessary.

Child↗

Obesity and beta-blockers: influence of body fat on their kinetics and cardiovascular effects.

Beta-blockers are among the most widely used antihypertensive drugs. They differ from each other in regard to several factors such as: beta-agonist activity, beta 1-selectivity and solubility. Aim of this work was to evaluate the influence of obesity on the kinetics and the antihypertensive effect of two Beta-blockers with different solubility such as: the water-soluble, atenolol and the liposoluble, metoprolol. The study was carried out according to an open randomized cross-over design. Eight obese hypertensive patients, after a two week washout period, were randomly allocated to a four week treatment. After a two week intermediate washout period, each patient switched to the other treatment for an additional four week period. On the first and the last day of each treatment the subjects were hospitalized to collect blood samples for the assay of the two drugs and to measure cardiovascular parameters. Obesity does not exert any effect on the kinetics of the water-soluble beta-blocker, atenolol, while markedly interferes with that of the liposoluble, without any apparent influence on its anti-hypertensive effect. These findings extend to obese hypertensives the concept that the plasma concentrations of beta-blocking agents are not reliable predictors of their therapeutic effect.

Adipose Tissue↗

A randomised controlled trial to investigate the effect of a high fibre diet on blood pressure and plasma fibrinogen.

Two hundred and one subjects (147 men and 54 women) were randomly allocated to either a high cereal fibre diet or a low cereal fibre diet for four weeks. Each group then followed the alternative diet for a further four weeks. Cereal fibre intakes were 19g/d (31 g/d 21 g/d total fibre) and 6g/d (19g/d total fibre) on the high and low fibre diets respectively (p less than 0.001). Energy, protein, fat, carbohydrate, and alcohol intakes calculated from weighed intake records did not differ between the two diets, although there was a slight difference in body weight, the mean being 0.3 kg heavier at the end of the high fibre period. The high cereal fibre diet had no detectable effect on blood pressure or plasma fibrinogen.

Adolescent↗

A random walk model for evaluating clinical trials involving serial observations.

For clinical trials where the variable of interest is ordered and categorical (for example, disease severity, symptom scale), and where measurements are taken at intervals, it might be possible to achieve a greater discrimination between the efficacy of treatments by modelling each patient's progress as a stochastic process. The random walk is a simple, easily interpreted model that can be fitted by maximum likelihood using a maximization routine with inference based on standard likelihood theory. In general the model can allow for randomly censored data, incorporates measured prognostic factors, and inference is conditional on the (possibly non-random) allocation of patients. Tests of fit and of model assumptions are proposed, and application to two therapeutic trials of gastroenterological disorders are presented. The model gave measures of the rate of, and variability in, improvement for patients under different treatments. A small simulation study suggested that the model is more powerful than considering the difference between initial and final scores, even when applied to data generated by a mechanism other than the random walk model assumed in the analysis. It thus provides a useful additional statistical method for evaluating clinical trials.

Algorithms↗

The Christie hospital adjuvant tamoxifen trial--status at 10 years.

From November 1976 to June 1982, a randomised clinical trial was carried out at the Christie Hospital, Manchester, to test the clinical efficacy of tamoxifen (TAM) as an adjuvant to surgery for patients with operable breast carcinoma. Following surgery, premenopausal women were randomly allocated to have either TAM 20 mg day-1 for one year or an irradiation menopause (the previous standard treatment). Postmenopausal women had TAM 20 mg day-1 for one year or no further treatment (Controls). A total of 1005 patients were entered into the trial of whom 961 are evaluable at 10 years from the inception. At 10 years the analysis shows no significant difference in overall and disease free survival between premenopausal women given TAM or an irradiation menopause. For premenopausal node negative patients there would appear to be a trend in favour of the TAM treated patients with a 93% ten year survival vs. 82% for the irradiation menopause group (P = 0.09). When the disease free survival of all 961 patients is analysed, allowing for node status, then there is a marked trend in favour of the TAM treated patients (P = 0.07). Of the patients originally allocated to TAM 47% had an irradiation menopause on relapse and 73% of the postmenopausal control patients had TAM on relapse. The incidence of side effects and second primary tumours is discussed as well as the possible effects of varying the length of time over which adjuvant TAM is administered.

Adult↗

Serum prolactin assays have no prognostic value in treatment of prostatic cancer by orchidectomy or estrogens.

Eighty patients (54-75 years) with cytologically and/or histologically confirmed cancer of the prostate (CAP) were randomly allocated to either orchidectomy (ORX, n = 41) or combined intramuscular and oral estrogen treatment (ESTR, n = 39). Serum levels of prolactin (PRL) were determined prior to treatment and 6, 12 and 24 months after initiation of the treatment. In the ORX group, 32 patients responded to the treatment and 9 did not. In the ESTR group, 27 patients responded and 12 did not. Serum PRL levels were significantly increased by ESTR treatment in responders as well as in nonresponders, but were not affected by ORX. There were no differences in PRL values between responders and nonresponders at any time in any of the two treatment groups. It is concluded that serum PRL assays have no prognostic value in the employed endocrine treatment of CAP.

Aged↗

A double-blind controlled trial of high dose methylprednisolone in patients with multiple sclerosis: 1. Clinical effects.

A randomised double-blind, placebo-controlled trial of high-dose, pulsed intravenous methylprednisolone was carried out in 50 individuals with multiple sclerosis; 22 patients were in acute relapse and 28 had chronic progressive disease. After a baseline assessment using the Kurtzke functional and expanded disability status scales each patient was randomly allocated to intravenous treatment with methylprednisolone (500 mg) or a saline placebo administered as a single daily dose for 5 days. Clinical assessments were repeated at 1 and 4 weeks after starting treatment. The results from all 50 patients showed a highly significant effect in favour of methylprednisolone treatment (p less than 0.001). In patients with relapse, there was a significant decrease in clinical disability scores at 1 and 4 weeks in the methylprednisolone treated group compared with controls (p less than 0.05 for each comparison). In the chronic progressive group, disability scores at 4 weeks only were significantly lower after treatment with methylprednisolone (p less than 0.01), mainly attributable to improvement in pyramidal function.

Adolescent↗

Performance evaluation of heat-stressed commercial broilers provided water-cooled floor perches.

A study was conducted to determine whether water-cooled floor perches would be utilized by commercial broilers exposed to a constant hot ambient environment; and subsequently, whether utilization of these perches would improve performance beyond those provided uncooled floor perches. A total of 330 day-old commercial broiler chicks were randomly allocated to six pens (2.44 m2) in an environmentally controlled facility and maintained in a thermoneutral brooding environment for 16 days. Following this period, 240 birds were selected on a body weight basis and randomly assigned to the six pens. A perch constructed from steel pipe (2.44 m length, 5.0 cm diameter) was then placed diagonally on the litter covered floor of each pen. The birds were first exposed to a thermoneutral period (27.7 C), during which time cooling of the perches in three replicate pens was initiated by circulating tap water. The other three experimental pens received ambient perches. Ambient temperature was then raised to 32.6 C for the following 4 wk. The results of the present study showed that utilization of water-cooled perches by broilers was greater (P less than or equal to .01) than ambient perch utilization throughout the 32.6 C period. Average daily gain was greatest (P less than or equal to .01) for broilers exposed to cool perches. Additionally, they consume more feed (P less than or equal to .05), on a daily basis, than those given ambient perches during the heat-stress period. Broilers exposed to water-cooled perches also had a more efficient gain to feed ratio (P less than or equal to .01). At the completion of the study, final body weight and total body weight gain were greater (P less than or equal to .05) for broilers given water-cooled perches compared with those exposed to ambient perches. Total amount of feed consumed and total feed efficiency were only moderately affected (P less than or equal to .10) by perch treatments. These results indicated that water-cooled perches were beneficial in improving broiler performance during periods of high environmental temperatures.

Animals↗