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PubMed1992

High frequency jet ventilation: use of the Bain system for entrainment.

The use of a Bain system to convey anaesthetic gases for entrainment during high frequency jet ventilation (HFJV) was evaluated by examining the effect of varying the fresh gas flow (Vf) on the end-tidal carbon dioxide (PECO2) in 46 ASA physical status I and II patients undergoing extracorporeal shock-wave lithotripsy (ESWL). Anaesthesia was induced with methohexitone (1-2 mg.kg-1), fentanyl (1-1.5 micrograms.kg-1) and vecuronium (0.1 mg.kg-1). After endotracheal intubation with a Mallinckrodt Hi-Lo Jet cuffed endotracheal tube, the patient was immersed in a water bath and HFJV at 150 breaths per minute was instituted with an Acutronic AMS 1000 jet ventilator attached to the side channel of the Hi-Lo tube. A Bain system was attached to the proximal end of the endotracheal tube to provide gases for entrainment. Anaesthesia was maintained with an intravenous infusion of methohexitone (5 mg.kg-1.h-1) and 50% nitrous oxide in oxygen for both the jetted and entrained gases. PECO2 was determined at 5-min intervals by a single-breath technique using a calibrated Engstrom Eliza capnograph. Thirty patients were randomly allocated to receive Vf's of 50 (Group 1), 75 (Group 2) and 100 (Group 3) ml.kg-1.min-1, respectively. A further eight patients (Group 4) received a Vf of 100 ml.kg-1.min-1 for 15 min, 75 ml.kg-1.min-1 for the next 15 min and 50 ml.kg-1.min-1 thereafter. In a further group of eight patients (Group 5), Vf was initially 25 ml.kg-1.min-1 for 10 min and was then switched off for the remainder of the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1986

Efficacy of combined treatment with oral and topical acyclovir in first episode genital herpes.

Fifty patients presenting with first episode genital herpes were randomly allocated to seven day treatment with either oral acyclovir plus 5% acyclovir cream or oral acyclovir plus matching placebo cream. Combined treatment with oral and topical acyclovir was associated with a shorter duration of itching in women alone (p = 0.04) but gave no clinical relief of other symptoms, the time to healing of lesions, or the subsequent recurrence rate. Concomitant topical treatment with 5% acyclovir cream confers no advantages on patients who receive oral acyclovir.

Acyclovir↗

PubMed1985

The efficacy of lower axillary sampling in obtaining lymph node status in breast cancer: a controlled randomized trial.

Four hundred and seventeen patients with operable breast cancer treated by simple mastectomy were randomly allocated to have node sampling or total axillary clearance. There was no significant difference in the incidence of node positivity. One hundred and thirty-five patients had node sampling and were randomized at the completion of this procedure to have axillary clearance or to have no further surgery. All node positive patients who went on to have a clearance had positive samples, confirming the accuracy of the sampling technique.

Breast Neoplasms↗

PubMed2005

Renoprotective effect of benazepril on diabetic nephropathy mediated by P42/44MAPK.

The effects of benazepril on P42/44MAPK, angiotensin II expression in renal tissue and renal pathological change of the experimental diabetic rats were assessed and the possible mechanism of benazepril's renoprotective effect was explored. Adult male Wistar rats, 11-12 weeks age, weighing initially 160 to 200 g were randomly allocated into 2 groups: control group (A, n = 6) and experimental group (n = 12). Diabetic rats in experimental group were rendered diabetic by intraperitoneal injection of Streptozotocin (60 mg/kg body weight), and randomly subdivided into B group (diabetic control) and C group (diabetic rats treated with benazepril, 6 mg/kg every day). Studies were performed 8 weeks after induction of diabetes. Twenty-four h urine of every rat was collected to detect urine creatinine. Serum glucose concentration and serum creatinine were determined by collecting blood samples from the inferior vena cava. Body and kidney weight were recorded. Creatinine clearance (Ccr) and ratio of kidney weight to body weight were calculated. Plasma and renal tissue angiotensin II concentration was assayed by radioimmunoassay (RIA). The phospo-p44/42MAPK protein expression was detected by Western-blot. The results showed that benazepril had no significant effect on the blood glucose level in diabetic rats in two experimental groups. Ccr and ratio of kidney weight to body weight were increased in group B (P < 0.01) as compared with normal rats at the end of the 8th week. At the end of the 8th week, Ccr in group C was lower than that in group B (P < 0.01). The ratio of kidney weight to body weight in group C was lower than that in group B at the 8th week. There were glomeruli hypertrophy and slight or moderate mesangium proliferation in diabetic rats, while there was fragmentally proliferative mesangium in group C at the end of the 8th week. Renal tissue angiotensin II concentration was significantly increased in group B, while benazepril could significantly decrease the concentration of angiotensin II in renal tissue. The expression of the phospo-p44/42MAPK protein in group B was increased as compared with group A, while it was decreased in group C as compared with group B. P42/ 44MAPK pathway participated in the pathogenesis of diabetic nephropathy. Benazepril can eliminate high filtration of glomeruli, decrease proteinuria, and eliminate renal hypertrophy as well as renal destruction. Renoprotective effect of benazepril in diabetic rats may be partly related to the inhibition of angiotensin II -P42/44MAPK pathway.

Angiotensin II↗

PubMed1989

Preterm labour in twin pregnancies: can it be prevented by hospital admission?

Women attending a twin pregnancy antenatal clinic underwent cervical palpation to calculate a cervical score by subtracting dilatation from length. Those with a score of -2 or less at or before 34 weeks are at especially high risk of preterm labour. A total of 139 such women were randomly allocated either to receive bed-rest in hospital or to continue conventional outpatient management. No beneficial effect of bed-rest could be identified in prolonging twin pregnancy or improving fetal outcome.

Bed Rest↗

PubMed1986

Is driving gas flow rate clinically important for nebulizer therapy?

Ten patients with stable asthma were studied to see whether the flow rate used to drive a nebulizer was clinically important. Each received 1 mg of salbutamol in 2 ml of physiological saline via a Sandoz 'Lifeline' nebulizer driven by piped oxygen at 8, 6 and 4 litres/min on separate randomly allocated occasions. Although the time for nebulization was significantly longer as flow rate was reduced, there was no significant difference in the bronchodilator response.

Adult↗

PubMed1982

A double-blind placebo-controlled trial of methylprednisolone pulse therapy in active rheumatoid disease.

To confirm the findings of uncontrolled trials that methylprednisolone pulse therapy (MPPT) is a safe treatment for active rheumatoid disease, a double-blind trial was conducted in which 20 patients with active rheumatoid disease were randomly allocated to receive an infusion of either 1 g methylprednisolone or placebo. Methylprednisolone produced significant improvement in all clinical variables measured, a benefit which was sustained for at least 6 weeks. The placebo produced only transient improvement in some of the clinical variables measured. when the 10 placebo groups patients were later given an infusion of 1 g methylprednisolone, they too showed significant clinical benefit. The methylprednisolone also gave rise to improvements in some haematological and biochemical variables.

Adult↗

PubMed1985

Randomised controlled trial of azathioprine withdrawal in autoimmune chronic active hepatitis.

To assess the value of azathioprine in the maintenance therapy of autoimmune chronic active hepatitis a controlled trial of azathioprine withdrawal was carried out in 50 patients who had been maintained in remission on a combination of azathioprine and prednisolone. The patients were randomly allocated to remain on combination therapy (23) or to discontinue azathioprine (27). These 2 groups were comparable at the start of the study. Over a follow-up period of up to 3 years, biochemical and histological relapse occurred in 8 patients in the azathioprine-withdrawal group but in only 1 patient in the combination-therapy group. Cumulative probability of relapse was 32% among the patients in the withdrawal group, compared with 6.0% for those in the combination group.

Adult↗

PubMedDate not supplied

Estimating the causal effects of treatment.

OBJECTIVE: To provide a relatively non-technical review of recent statistical research on the analysis and interpretation of the results of randomised controlled trials in which there are possibly all three of the following types of protocol violation: non-adherence to allocated treatment, contamination (that is, patients receiving treatments other than the one to which they were allocated) and attrition (missing outcome data). METHODS: The estimation methods involve the use of potential outcomes (counterfactuals) in the definition of a causal effect of treatment and in drawing valid inferences concerning its size. RESULTS: The methods are explained through the use of simple arithmetical expressions involving the counts from three-way contingency tables (Outcome by Treatment Received by Random Allocation). Illustration is provided through the use of a hypothetical data set. CONCLUSIONS: Recent advances in statistical methodology enable one to estimate treatment effects from the results of randomized trials in which the treatment actually received is not necessarily the one to which the patient was allocated. These methods allow one to make adjustments to allow for both non-compliance and loss to follow-up. Even for such a 'broken' randomised trial, inference concerning causal effects is safer than that from data arising from an observational study that never involved random allocation in the first place.

Humans↗

PubMed1986

Evaluation of therapeutic modalities in the control of Hodgkin's disease.

The results achieved in three different studies carried out on patients affected by Hodgkin's disease are discussed. In study No. 1, 58 patients with pathological Stage I-II were treated with only a "Mantle" field irradiation. The complete remission (CR) rate was 98% with an actuarial overall survival of 90%, and a median of follow-up of 80 months. Thirty-one percent of patients relapsed. In study No. 2, 42 patients were randomly allocated to receive only MOPP chemotherapy versus extended field irradiation; CR rate was 68 and 95%, respectively (p less than 0.05). The overall survival rate was 100% in the radiotherapy group and 82% in the MOPP group. No relapses have been observed in patients treated with MOPP. In study No. 3, 218 patients affected by advanced Stage HD were randomly treated with 6 cycles of MOPP chemotherapy versus 6 cycles of ABVD chemotherapy. In the MOPP group the CR rate, the relapse-free survival rate (RFS), and overall survival (OS) rates at 60 months were 77, 68, and 76% respectively, whereas, in the ABVD group the CR, the RFS, and OS rates at 60 months were 75, 77 and 80% respectively, (p less than 0.05). These data and statistical comparisons are analyzed.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1982

Radiation and nitroimidazoles in supratentorial high grade gliomas: a second clinical trial.

As a continuation of a previous controlled trial using "high-dose" metronidazole as a specific sensitizer of hypoxic cells, we used a more efficient nitroimidazole derivative (misonidazole, MISO) in combination with higher doses of radiation in patients with supratentorial high-grade astrocytomas. Sixty-six patients were stratified according to functional level and histological grading, and randomly allocated within 2 weeks of operation of 1 of 3 therapeutic groups: 1, conventional radiation alone; 2, large fractions of radiation with high-dose metronidazole; and 3, radiation as in Group 2 but with equitoxic doses of MISO. We examined survival as the principal end-point of the study. Neither by increasing the dose of radiation over the previous study, nor by using a more efficient sensitizer, were we able to improve survival over the current conventional daily fractionated radiation.

Adult↗

PubMed1983

Myocardial protective effect of maintained beta-blockade in aorto-coronary bypass surgery.

Twenty-nine patients were randomly allocated to two groups before undergoing aorto-coronary bypass surgery. In one group the beta-blocking medication was withdrawn three days preoperatively, and in the other group it was maintained. The patients in the latter group were additionally given 100 mg metoprolol per os two hours before surgery. The degree of myocardial injury, as judged from cumulated activity of S-CK B, was less when the beta-blockade was maintained.

Adrenergic beta-Antagonists↗

PubMed1987

An experiment to change detection and management of mental morbidity in primary care.

A randomized clinical trial was conducted in a group practice for the primary care of adult patients to address the effect of feedback to providers of information from a psychiatric screening questionnaire, the General Health Questionnaire (GHQ). The practice is staffed by faculty, residents, and health care extenders of The Johns Hopkins University School of Medicine's Division of Internal Medicine. The patient population was drawn mainly from the inner city community in Baltimore that surrounds the hospital, where the practice is physically based. The GHQ was administered at the time of a regular visit to the practice and results made available to the clinicians for randomly allocated subsamples of their patients. The study results showed that feedback of GHQ information led to only marginal effects on overall detection of mental health problems among the patients in general. However, marked increases in detection occurred among the elderly, blacks, and men, subgroups that ordinarily have relatively low rates of detection of mental morbidity by primary care practitioners. Feedback of GHQ information did not affect management.

Adolescent↗

PubMed1979

Psychological rehabilitation after myocardial infarction.

The value of psychological counselling in rehabilitating patients after myocardial infarction was assessed. A total of 143 men who had recently had a myocardial infarction were randomly allocated to either a group receiving intensive rehabilitation or a control group, their outcome being examined after six months. Patients with neurotic, introverted personalities had a poor outcome in the control group but a satisfactory outcome when rehabilitated. Neurotic personalities responded to help, and rehabilitative measures did not increase neurosis. In addition all patients with a negative attitude towards their illness and future had a poor outcome but those with a positive attitude did well. Selection by simple methods of patients who would benefit from psychological rehabilitation seems desirable.

Adult↗

PubMed1979

A comparative trial of two oral cholecystographic contrast media--iocetamic acid (Cholebrin) and iopanoic acid (Telepaque).

A comparative trial was made between two oral cholecystographic agents, iocetamic acid (Cholebrin) and iopanoic acid (Telepaque), Fifty patients were given Cholebrin and another 50 were given Telepaque by random allocation. The cholecystographic qualities of the two contrast media showed no significant difference. It was noted that contrast medium within the bowel at the time of the investigation tended to be homogeneous rather than granular with Cholebrin, and the significance of this is discussed. Gastrointestinal side-effects were common with both contrast media, but there was a significantly lower incidence of diarrhoea with Cholebrin than with Telepaque. Various biochemical parameters of hepatic and renal function were measrued in 40 random patients and showed no clinically significant alteration following ingestion of the contrast media.

Administration, Oral↗

PubMed1985

A review of clinical trials in the surgical treatment of cerebrovascular disease.

The major treatable risk factors in thromboembolic stroke are hypertension and transient ischemic attacks (TIA). Two prospective hospital series of TIA provide no evidence that either medical or surgical therapy is superior to the other or to supportive treatment. However, the treated groups were not shown to be comparable. Only the joint cooperative study on extracranial arterial occlusion provided random allocation of TIA patients to surgery or no surgery. The published conclusion comparing course after discharge was that surgery was of significant benefit. However, when the groups were compared from the point of randomization and when later TIA alone were excluded, there was not even a suggestion that the surgery groups did better than the others. Sample size was such, though, that a possible reduction of stroke occurrence by one-half could not be excluded with the data at hand, leaving the ultimate decision as to the potential value of surgery in TIA to the clinician.

Arterial Occlusive Diseases↗

PubMed1988

Low-dose antacids and pirenzepine in the treatment of patients with non-ulcer dyspepsia and erosive prepyloric changes. A randomized, double-blind, placebo-controlled trial.

One hundred consecutive patients with non-ulcer dyspepsia (NUD) and the endoscopic diagnosis of erosive prepyloric changes (EPC) were included in a 4-week double-blind, placebo-controlled trial. The patients were randomly allocated to treatment with either Al-Mg antacids (one tablet four times daily; acid-neutralizing capacity, 120 mmol/day) or antacid placebo, in combination with either pirenzepine (50 mg twice daily) or pirenzepine placebo. Ninety patients completed the study. Symptoms improved during the 4 weeks in all treatment groups, irrespective of the treatment given. Neither pirenzepine nor antacid was significantly superior to placebo. Re-endoscopy after 4 weeks of treatment showed no significant change in the EPC grade. No serious side effects were observed, but xerostomia occurred more frequently in patients treated with pirenzepine than in those treated with placebo (p less than 0.01).

Adult↗

PubMedDate not supplied

Role of carotid endarterectomy in asymptomatic carotid stenosis. A Veterans Administration Cooperative Study.

A multi-centered cooperative study is being undertaken to determine the role of carotid endarterectomy in the treatment of asymptomatic carotid stenosis. The primary objective is to compare the incidence of transient ischemic attacks, stroke, and death in previously asymptomatic patients with arteriographically confirmed internal carotid stenoses (greater than or equal to 50%) randomly allocated to carotid endarterectomy and aspirin therapy versus aspirin therapy alone. Ten Veterans Administration Medical Centers (VAMC) in the United States are participating. The study will be conducted over a period of eight years. The first three years will be devoted to acquiring and randomizing patients, after which all patients will be followed clinically for a minimum of five years. It is anticipated that approximately 500 patients will be recruited into the study.

Arterial Occlusive Diseases↗