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PubMed2001

Endoscopic versus open subfascial division of incompetent perforating veins in the treatment of venous leg ulceration: long-term follow-up.

PURPOSE: Subfascial division of incompetent perforating veins seems to be a successful treatment for patients with venous leg ulceration (CEAP 6). For postoperative wound complications, endoscopic techniques are more common than open subfascial division of incompetent perforating veins (Linton procedure). We investigated the long-term results of ulcer healing and recurrence rates and compared them with preoperative and postoperative duplex findings. METHODS: Patients with venous ulceration on the medial side of the lower leg were randomly allocated to endoscopic exploration or open exploration by means of the modified Linton approach. Ulcer healing and recurrence rates were documented. RESULTS: Thirty-nine patients were randomly allocated to exploration, 19 patients to open subfascial division of incompetent perforating veins (Linton group), and 20 patients to subfascial endoscopic division of incompetent perforating veins (SEPS group). During the follow-up period, four patients in the SEPS group died, all of causes other than the venous leg ulcer. Because of a squamous cell carcinoma that had developed in the venous ulcer, one patient in the SEPS group underwent a below-knee amputation. In a mean follow-up period of 50.6 months, the venous ulceration of all 18 patients in the Linton group who were available for follow-up initially healed. The recurrence rate in this group was 22% (4 patients). In the SEPS group, the mean follow-up period for 19 patients was 46.1 months, with the ulceration healing in 17 patients and a recurrence rate of 12% (2 patients). The presence of deep venous incompetence (DVI) did not influence the recurrence rates (P =.044, Fisher exact test), but it significantly influenced the development of new incompetent perforating veins (3 of 10 without DVI; 7 of 10 with DVI; P =.011, binomial test). CONCLUSION: The long-term follow-up results of the endoscopic division of perforating veins are comparable with those of the open division of perforating veins (modified Linton procedure).

Adult↗

PubMed2001

Lithium for maintenance treatment of mood disorders.

BACKGROUND: Mood disorders are common, disabling and tend to be recurrent. They carry a high risk of suicide. Maintenance treatment, aimed at the prevention of relapse, is therefore of vital importance. Lithium has been used for some years as the mainstay of maintenance treatment in bipolar affective disorder, and to a lesser extent in unipolar disorder. However, the efficacy and effectiveness of prophylactic lithium therapy has been disputed. Low suicide rates in lithium-treated patients have led to claims that lithium has a specific anti-suicidal effect. If so, this is of considerable importance as treatments for mental disorders in general have not been shown convincingly to be effective in suicide prevention. OBJECTIVES: 1. To investigate the efficacy of lithium treatment in the prevention of relapse in recurrent mood disorders. 2. To examine the effect of lithium treatment on consumers' general health and social functioning, its acceptability to consumers, and the side-effects of treatment. 3. To investigate the hypothesis that lithium has a specific effect in reducing the incidence of suicide and deliberate self-harm in persons with mood disorders. SEARCH STRATEGY: The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR) and The Cochrane Controlled Clinical Trials Register (CCTR) were searched. Reference lists of relevant papers and major text books of mood disorder were examined. Authors, other experts in the field and pharmaceutical companies were contacted for knowledge of suitable trials, published or unpublished. Specialist journals concerning lithium were hand searched. SELECTION CRITERIA: Randomised controlled trials comparing lithium with placebo, where the stated intent of treatment was maintenance or prophylaxis. Participants were males and females of all ages with diagnoses of mood disorder. Discontinuation studies (in which all participants had been stable on lithium for some time before being randomised to either continued lithium treatment or placebo substitution) were excluded. DATA COLLECTION AND ANALYSIS: Data were extracted from the original reports independently by two reviewers. The main outcomes studied were related to the objectives stated above. Data were analysed for all diagnoses of mood disorder and for bipolar and unipolar disorder separately. Data were analysed using Review Manager version 4.0. MAIN RESULTS: Nine studies were included in the review, reporting on 825 participants randomly allocated to lithium or placebo. Lithium was found to be more effective than placebo in preventing relapse in mood disorder overall, and in bipolar disorder. The most consistent effect was found in bipolar disorder (random effects OR 0.29; 95% CI 0.09 to 0.93 ). In unipolar disorder, the direction of effect was in favour of lithium, but the result (when heterogeneity between studies was allowed for) did not reach statistical significance. Considerable heterogeneity was found between studies in all groups of patients. The direction of effect was the same in all studies; no study found a negative effect for lithium. Heterogeneity may have been due to differences in selection of participants, and to differing exposures to lithium in the pre-study phase resulting in variable influence of a discontinuation effect. There was little reported data on overall health and social functioning of participants under the different treatment conditions, or on the participants' own views of their treatment. Descriptive analysis showed that assessments of general health and social functioning generally favoured lithium. Small absolute numbers of deaths and suicides, and the absence of data on non-fatal suicidal behaviours, made it impossible to draw meaningful conclusions about the place of lithium therapy in suicide prevention. REVIEWER'S CONCLUSIONS: This systematic review indicates that lithium is an efficacious maintenance treatment for bipolar disorder. In unipolar disorder the evidence of efficacy is less robust. This review does not cover the relative efficacy of lithium compared with other maintenance treatments, which is at present unclear. There is no definitive evidence from this review as to whether or not lithium has an anti-suicidal effect. Systematic reviews and large scale randomised studies comparing lithium with other maintenance treatments (e.g. anti-convulsants, antidepressants) are necessary. Outcomes relating to death and suicidal behaviour should be included in all future maintenance studies of mood disorder.

Antimanic Agents↗

PubMed1999

Pain after primary inguinal herniorrhaphy: influence of surgical technique.

BACKGROUND: Pain is an important problem after ambulatory hernia repair. To assess the influence of the surgical technique on postoperative pain, two separate randomized, patient-blinded, controlled trials were performed in men with an indirect inguinal hernia. STUDY DESIGN: In study A, 48 patients with an internal inguinal ring smaller than 1.5 cm were randomly allocated to either simple extirpation of the hernial sac or extirpation plus annulorrhaphy. In study B, 84 patients with an internal inguinal ring wider than 1.5 cm were randomly allocated to extirpation plus annulorrhaphy or extirpation plus Lichtenstein mesh repair (modified). All operations were performed under unmonitored local anesthesia with standardized perioperative analgesia using methadone and tenoxicam. Pain was scored daily for the first postoperative week and after 4 weeks on a four-point verbal-rank scale (no, light, moderate, or severe pain) during rest, while coughing, and during mobilization (rising to the sitting position). Use of supplementary analgesics (paracetamol) was recorded. Cumulative daily pain scores for the first postoperative week and the number of patients who used supplementary analgesics were the main outcome measures. RESULTS: There were no significant differences in cumulative pain scores or use of supplementary analgesics between the treatment groups in either study. Cumulative pain scores were significantly higher during coughing and mobilization than during rest in both studies. CONCLUSIONS: Choice of surgical technique for open repair of a primary indirect inguinal hernia has no influence on postoperative pain.

Adolescent↗

PubMed1976

A headache protocol for nurses: effectiveness and efficiency.

To test the effectiveness and efficiency of a nurse-administered protocol for headache in the primary care setting, we conducted a prospective controlled trial. Two hundred three randomly allocated patients were evaluated by nurses using the protocol who managed independently 55.2% of the patients and received physician consultation on the others. A total of 193 patients were randomly allocated to the physician-control group. Nurse-protocol group patients experienced equivalent symptomatic relief and expressed significantly greater satisfaction with the care they had received than did patients in the physician-control group. A retrospective study of the presenting findings in patients with serious diseases of the CNS provided evidence supporting the safety of the protocol logic. We conclude that nurse-protocol management of headache in this primary care practice was effective and efficient.

Ambulatory Care↗

PubMed1998

Tamoxifen in treatment of hepatocellular carcinoma: a randomised controlled trial. CLIP Group (Cancer of the Liver Italian Programme)

BACKGROUND: Results from small randomised trials on tamoxifen in the treatment of hepatocellular carcinoma (HCC) are conflicting. We studied whether the addition of tamoxifen to best supportive care prolongs survival of patients with HCC. METHODS: Patients with any stage of HCC were eligible, irrespective of locoregional treatment. Randomisation was centralised, with a minimisation procedure accounting for centre, evidence of disease, and time from diagnosis. Patients were randomly allocated best supportive care alone or in addition to tamoxifen. Tamoxifen was given orally, 40 mg per day, from randomisation until death. RESULTS: 496 patients from 30 institutions were randomly allocated treatment from January, 1995, to January, 1997. Information was available for 477 patients. By Sept 15, 1997, 119 (50%) of 240 and 130 (55%) of 237 patients had died in the control and tamoxifen arms, respectively. Median survival was 16 months and 15 months (p=0.54), respectively. No differences were found within subgroups defined by prognostic variables. Relative hazard of death for patients receiving tamoxifen was 1.07 (95% CI 0.83-1.39). INTERPRETATION: Our findings show that tamoxifen is not effective in prolonging survival of patients with HCC.

Adult↗

PubMed2000

The effects of cell size and ploidy on cell allocation in mouse chimaeric blastocysts.

In a previous study of mouse tetraploid<-->diploid chimaeric blastocysts, tetraploid cells were found to be more abundant in the trophectoderm than the inner cell mass (ICM) and more abundant in the mural trophectoderm than the polar trophectoderm. This non-random allocation of tetraploid cells to different regions of the chimaeric blastocyst may contribute to the restricted tissue distribution seen in post-implantation stage tetraploid<-->diploid chimaeras. However, the tetraploid and diploid embryos that were aggregated together differed in several respects: the tetraploid embryos had fewer cells and these cells were bigger and differed in ploidy. Each of these factors might underlie a non-random allocation of tetraploid cells to the chimaeric blastocyst. A combination of micromanipulation and electrofusion was used to produce two series of chimaeras that distinguished between the effects of cell size and ploidy on the allocation of cells to different tissues in chimaeric blastocysts. When aggregated cells differed in cell size but not ploidy, the derivatives of the larger cell contributed significantly more to the mural trophectoderm and polar trophectoderm than the ICM. When aggregated cells differed in ploidy but not cell size, the tetraploid cells contributed significantly more to the mural trophectoderm than the ICM. In both experiments the contributions to the polar trophectoderm tended to be intermediate between those of the mural trophectoderm and ICM. These experiments show that both the larger size and increased ploidy of tetraploid cells could have contributed to the non-random cell distribution that was observed in a previous study of tetraploid<-->diploid chimaeric blastocysts.

Animals↗

PubMed2003

Ant venom immunotherapy: a double-blind, placebo-controlled, crossover trial.

BACKGROUND: The jack jumper ant Myrmecia pilosula is responsible for about 90% of ant venom anaphylaxis in southeastern Australia. We aimed to establish whether M pilosula venom immunotherapy (VIT) prevents lifethreatening sting anaphylaxis in otherwise healthy adults. METHODS: We did a double-blind, placebo-controlled crossover trial of M pilosula VIT. Participants were randomly allocated either immunotherapy, in accordance with the semirush hyposensitisation regimen, or placebo. The primary endpoint was systemic reaction after a deliberate sting challenge. Analysis was per protocol. FINDINGS: We randomly allocated 68 healthy volunteers (aged 20-63 years) who were allergic to M pilosula venom to placebo (33) and VIT (35). Four on placebo were stopped early and 12 on VIT had their treatment allocations revealed before the sting challenge, thus 29 on placebo and 23 on VIT were included in the primary analysis. Objectively defined systemic reactions to sting challenges arose in 21 of 29 participants (72%) on placebo (8 reactions were associated with hypotension) and none of 23 on VIT (p<0.0001). Of the remaining 12 on VIT who underwent sting challenges after treatment allocations were revealed, only one reacted to sting challenge with transient urticaria that did not require treatment. After crossover of the placebo group to VIT, one of 26 had a reaction to sting challenge (transient urticaria). In all patients who had VIT, we recorded objective systemic reactions in 22 of 64 (34%) during VIT; two of which were hypotensive. INTERPRETATION: In well motivated, highly allergic, but otherwise healthy adults, VIT is highly effective in prevention of M pilosula sting anaphylaxis. The risk of systemic reactions during VIT means that treatment should be given where there is immediate access to resuscitation facilities.

Adult↗

PubMed1989

Chlorthalidone does not increase the hypotensive effect of nifedipine in essential hypertensives: a crossover multicentre study.

To determine whether the combination of nifedipine + chlorthalidone exerts an additive antihypertensive effect when compared with single-drug treatment, we studied 66 uncomplicated essential hypertensives, with diastolic blood pressure of greater than 100 and less than 115 mmHg. At the end of a 1-month washout placebo period, using a double-blind crossover design, the patients were randomly allocated to nifedipine (20 mg twice a day), chlorthalidone (25 mg once a day), the two drugs combined at the same doses and the corresponding placebo. Compared with the randomly allocated placebo, the three active treatments significantly reduced blood pressure without changing the heart rate or body weight. Both the absolute and percentage decreases in mean blood pressure induced by nifedipine and the combination compared with placebo were similar and significantly greater than those induced by chlorthalidone. Taken together, these data show that the combination of nifedipine + chlorthalidone does not exert any additive antihypertensive effect compared with nifedipine alone. This finding indicates that the combination of a dihydropyridine calcium antagonist + a thiazide diuretic is probably devoid of any particular clinical significance in the treatment of uncomplicated essential hypertensives.

Adult↗

PubMed1999

Searching for the evidence in pre-hospital care: a review of randomised controlled trials. On behalf of the Ambulance Response Time Sub-Group of the National Ambulance Advisory Committee.

OBJECTIVES: To identify randomised controlled trials (RCTs) which evaluate aspects of pre-hospital care; to perform categorisation by theme; to compare the sensitivity and precision of the search databases. DATA SOURCES: August 1997 updates of MEDLINE and EMBASE databases, using the Datastar online system. Papers published in 1987 or later were included, with no language restrictions. STUDY SELECTION: A trial was eligible for inclusion if it was judged, by two independent and blinded assessors, that participants followed up in the trial were definitely or possibly assigned prospectively to one of two or more alternative forms of healthcare with random allocation or a quasi-random method of allocation. RESULTS: The literature search retrieved 849 papers, of which 569 (67%) were in MEDLINE and 486 (57%) in EMBASE. Forty one (5%) were confirmed as reports of RCTs or quasi-RCTs, and the total number of individual trials was 38. Ten of these trials dealt with thrombolytic drugs; 14 were concerned with other drugs, 12 with equipment, and two with other interventions. Four trials were based on a sample size of more than 1000, and seven reported a statistically significant effect on mortality. All 41 papers were in EMBASE, and all but one were also in MEDLINE. CONCLUSIONS: Evidence based policy making with respect to the organisation of pre-hospital services cannot depend on RCTs. In the current relative absence of such evidence, practitioners and decision makers must use alternative information sources. A future review could examine a broader range of literature and be based on a wider search of published and unpublished material.

Abstracting and Indexing↗

PubMed2003

[Ethical problems in randomized clinical studies from the aspect of statistics. Part II: when should patient randomization be stopped of modified?].

The ethical responsibility to the randomized study participants demands that the results be monitored during the course of the trial. The interim evaluation of the trial results may lead to the premature stopping. However, the repeated statistical testing inflates the probability of false positive error. Hence statistical adjustments are necessary. The probabilistic rules for the random allocation of patients may be changed during the course of the trial according to the observed responses.

Humans↗

PubMed2000

Peripheral retinal ablation for threshold retinopathy of prematurity in preterm infants.

BACKGROUND: This section is under preparation and will be included in the next issue. OBJECTIVES: In premature infants with threshold retinopathy of prematurity (ROP) does peripheral retinal ablation, by any means, reduce the incidence of adverse ophthalmic outcome? SEARCH STRATEGY: The standard search strategy of the Cochrane Neonatal Review Group was used. This included a search of the Cochrane Neonatal Group Register of Clinical Trials, MEDLINE, EMBASE, previous reviews including cross references, abstracts from pediatric and ophthalmologic meetings, letters and expert informants. Search terms included "Retinopathy of Prematurity" [MeSH Terms], "Retrolental Fibroplasia" [All Fields] and "Lightcoagulation" [All Fields] or "Cryosurgery" [All Fields]. In addition, a personal bibliographic database was used as a cross-reference. SELECTION CRITERIA: All trials in human premature infants with threshold ROP utilizing random or quasi random allocation to either peripheral retinal ablation of the avascular retina, by any means, or concurrent control group with independent outcome assessment were initially selected for review. Following methodologic review, only studies using random allocation were selected for data extraction. DATA COLLECTION AND ANALYSIS: Relevance and validity were assessed by the two authors and consensus reached. Each author extracted clinical outcomes from valid reports independently. Data analysis was conducted according to the standards of the Cochrane Neonatal Review Group. MAIN RESULTS: Two randomised trials were identified. Data from these studies show that peripheral retinal ablation reduces the risk of (1) early unfavorable retinal structure from 47. 9% to 28.1% (absolute risk reduction 19.8% [95% CI 27.9 - 11.8%]), (2) unfavorable retinal structure in early childhood from 44.3% to 26.3% (absolute risk reduction 18% [95% CI 27.0 - 9.1%]) and (3) unfavorable visual acuity in early childhood from 63% to 50.6% (absolute risk reduction 12.2% [95% CI 21.2 - 3.1]). In addition, visual fields in sighted eyes were slightly smaller in the treated (51.3 degrees +/- 11.8 degrees ) group as compared to the control (58.2 degrees +/- 14.5 degrees ) group. REVIEWER'S CONCLUSIONS: Peripheral retinal ablation reduces the incidence of adverse ophthalmic outcome in premature infants with threshold ROP. In sighted eyes, peripheral retinal ablation may reduce the size of the visual field. At this stage, long term outcomes remain unknown.

Cryosurgery↗

PubMed1991

Randomised controlled trial of day and in-patient psychiatric treatment. 2: Comparison of two hospitals.

Acutely ill patients presenting for admission in two district psychiatric services were randomly allocated to day-hospital or in-patient care. In both services a quarter of all admissions could not be allocated because they were too ill (half of these were compulsory admissions); these patients were predominantly manic and schizophrenic patients with pronounced psychotic symptoms and disturbed behaviour. In one service 80% (41/51) of patients randomly allocated to day-hospital treatment were successfully engaged in treatment compared with 54% (19/35) in the other service. This difference arose because only patients with mildly disturbed behaviour could be treated at the second day hospital. For patients who were successfully allocated, the outcome of treatment was similar in terms of psychiatric symptoms and social functioning. The results of a treatment trial for acutely ill patients in one district service cannot be generalised to other district services without due attention to the factors, such as staffing levels, which determine the degree of disturbed behaviour that can be tolerated in the day hospital.

Acute Disease↗

PubMed2003

A randomized sequential allocation study to determine the minimum effective analgesic concentration of levobupivacaine and ropivacaine in patients receiving epidural analgesia for labor.

BACKGROUND: This study was designed to determine and compare the minimum local analgesic concentrations of levobupivacaine and ropivacaine when used in epidural obstetric analgesia. METHODS: In a double-blind study, healthy women requiring epidural analgesia for labor pain were randomized to receive either ropivacaine or levobupivacaine. Drugs were administered as a 20-ml epidural bolus. The concentration of each started at 0.11% and increased or decreased at intervals of 0.01%, depending on the response of the previous patient, using the technique of up-down sequential allocation. Minimum local analgesic concentrations were calculated using the formula of Dixon and Massey. Efficacy was assessed using visual analog pain scores and motor and sensory block assessments, and safety was assessed by recording maternal and fetal/neonate vital signs and adverse events. RESULTS: Forty-seven patients received levobupivacaine, and 47 received ropivacaine. Minimum local analgesic concentrations for levobupivacaine (0.077%; 95% CI, 0.058-0.096%) were lower than those for ropivacaine (0.092%; 95% CI, 0.082-0.102%). The 0.015% difference was not statistically significant. There was no notable difference between treatment groups in the proportion of patients reporting drug-related adverse events. CONCLUSIONS: Levobupivacaine was 19% more potent than ropivacaine and provided similar safety results.

Adult↗

PubMed2002

Glycopyrronium and hypotension following combined spinal-epidural anaesthesia for elective Caesarean section in women with relative bradycardia.

The ability of glycopyrronium to reduce the severity of hypotension following subarachnoid block in parturients with a relative bradycardia was evaluated in a double-blind randomised controlled study. Women with a resting heart rate of < or = 80 beat x min(-1) presenting for elective Caesarean section were randomly allocated to receive either glycopyrronium 2 microg x kg(-1) or normal saline intravenously once positioned for combined spinal-epidural anaesthesia. Following spinal injection of 2.6 ml hyperbaric bupivacaine 0.5% and fentanyl 15 microg, women randomly allocated to the saline group were given 6 mg ephedrine so that all parturients received some prophylaxis against hypotension other than the fluid preload. Further ephedrine and fluid boluses were administered if mean arterial pressure fell 20% or more from resting values. Using a sequential analysis technique, analysis after the first 20 subjects indicated the study should be stopped, with no difference in ephedrine requirements or hypotension between the groups. We conclude that pretreatment with glycopyrronium 2 microg x kg(-1) is no more effective than 6 mg ephedrine in preventing hypotension following subarachnoid block in parturients with relatively low resting heart rates.

Adult↗

PubMed1997

Comparison of effects of albendazole sulfoxide on in vitro produced bovine embryos and rat embryos.

OBJECTIVE: To evaluate and compare effects of albendazole sulfoxide (ABZSO) on rat embryos and bovine embryos produced in vitro. ANIMALS: In vitro produced bovine embryos. Rat embryos recovered from naturally bred Sprague-Dawley rats. PROCEDURE: 4- and 8-cell bovine embryos were randomly allocated to ABZSO or vehicle control groups. After 48 hours, embryos were evaluated for cell number and blastomere morphology. Rat embryos of similar stages, flushed from the uterine tube on gestational day 2-5, were randomly allocated to treatment or control groups. After 24 hours, embryos were evaluated as described previously. RESULTS: 44% of control bovine embryos divided in culture (> or = 16-cell stage). Fifteen percent of the controls had morphologic abnormalities, including disparity in blastomere size and cytoplasmic vacuoles and stippling. Treated (> or = 1 microgram of ABZSO/ml) bovine embryos differed (P < 0.0001) from controls, with 4% development and 93% abnormal morphology. Forty-five percent of control rat embryos divided in culture. Treated (> or = 500 ng of ABZSO/ml) rat embryos differed (P < 0.0003) from controls with regard to ability to divide. There were no consistent morphologic abnormalities in rat embryos. CONCLUSIONS: In vitro produced bovine embryos were susceptible to ABZSO at a concentration > or = 1 microgram/ ml, resulting in decreased ability to divide and presence of gross morphologic abnormalities. Rat embryos produced in vivo and exposed in vitro to ABZSO at a concentration > or = 500 ng/ml had decreased ability to divide in culture. CLINICAL RELEVANCE: Despite severe effects of ABZSO (> or = 1 microgram/ml) on bovine embryo development in vitro, it is beyond the scope of this study to speculate whether a therapeutic dosage of albendazole (10 mg/kg of body weight) would result in necessary concentrations of ABZSO in vivo to disrupt embryogenesis.

Abnormalities, Drug-Induced↗

PubMed1994

Comparative trial of quinapril versus captopril in mild to moderate congestive heart failure. Quinapril/Captopril Congestive Heart Failure Study Group.

OBJECTIVE: To compare the efficacy and safety of captopril twice a day with quinapril once a day for the treatment of mild to moderate congestive heart failure in a multicentre, double-blind, randomly allocated, parallel-group, 12-week study. METHODS: Exercise capacity, M-mode echocardiographic left ventricular measurements and clinical signs and symptoms were evaluated. After a 2-week, single-blind, placebo washout period, the patients were randomly allocated to double-blind treatment with either captopril twice a day or quinapril once a day; the initial doses of 12.5 and 5 mg, respectively, were increased to 25 and 10 mg, respectively, in the first month, and 50 and 20 mg in the second and third months, as required to achieve adequate blood pressure control. Baseline diuretic and/or digitalis therapy was allowed during the study, so that the patients were maintained in a stable condition. RESULTS: Data from 70 captopril- and 76 quinapril-treated patients were analysed. Both angiotensin converting enzyme inhibitors displayed comparable efficacy. Both drugs were well tolerated, with a low drop-out rate (11.4% for captopril and 10.5% for quinapril). CONCLUSION: Treatment with 20 mg quinapril once a day was as effective and safe for the treatment of congestive heart failure as 100 mg captopril administered twice a day.

Aged↗

PubMed1998

Persistence of the activity of topical ivermectin against biting lice (Bovicola bovis).

To assess the persistence of the activity of topical ivermectin against a natural challenge with biting lice (Bovicola bovis), 90 mixed-breed cattle that had been treated to remove lice, were blocked by bodyweight within sex and randomly allocated to three treatments: untreated control, doramectin at 200 micrograms/kg by subcutaneous injection, and ivermectin at 500 micrograms/kg by topical application. Forty-five pens were blocked into three groups of 15, and the blocks of pens were randomly allocated to three 14-day challenge periods starting 21, 28 and 35 days after treatment. There were five pens per treatment for each challenge period, and one B bovis-infested donor calf was introduced into each pen containing two principal calves at the start of the challenge period for that block of pens. The calves were examined thoroughly for B bovis seven, 14 and 21 days after the introduction of the donors. There were no significant differences between the control and doramectin groups for the numbers of animals infested, or the geometric mean louse counts at the final examination for any of the challenge periods. At the final examination for each challenge period, the louse counts of the cattle treated with topical ivermectin were all zero, and significantly (P < 0.05) fewer cattle treated with topical ivermectin were infested than either the controls or cattle treated with doramectin.

Animals↗

PubMed1999

Reducing myoclonus after etomidate.

BACKGROUND: The authors hypothesized that myoclonus after etomidate is dose-related, could be suppressed when small doses of etomidate were administered before induction, and is unassociated with seizure-like activity on electroencephalogram (EEG). METHODS: Three studies were performed. In the first study, 36 men were randomly assigned to receive 0.025, 0.050, 0.075, 0.100, 0.200, or 0.300 mg/kg of etomidate. In a second crossover study, eight men were randomly allocated to receive either a pretreatment dose of 0.050 mg/kg etomidate or placebo 50 s before 0.300 mg/kg etomidate was injected. EEG was recorded for subjects in the first two studies. In a third study, 60 patients were randomly allocated to one of three pretreatment doses of etomidate: 0.030, 0.050, or 0.075 mg/kg before 0.300 mg/kg was given. RESULTS: In Study 1, myoclonus was not observed after 0.025 or 0.050 mg/kg etomidate. One volunteer had myoclonus after 0.075 mg/kg and another after 0.100 mg/kg etomidate; three had myoclonus after 0.200 mg/kg; and five after 0.300 mg/kg. Incidence of myoclonus was dose-related (P < or = 0.01). In Study 2, two volunteers (25%) with etomidate pretreatment had mild myoclonus compared to six (75%) with placebo pretreatment (P < or = 0.05). EEG changes, other than delta waves, were not seen during myoclonic epochs. In Study 3, myoclonus was less likely after the small pretreatment doses (0.030 or 0.050 mg/kg) than after the large dose (0.075 mg/kg, P < or = 0.01). CONCLUSIONS: Incidence and intensity of myoclonus after induction with etomidate are dose-related, suppressed by pretreatment, and unassociated with seizure-like EEG activity.

Adult↗