PubMed Health⌕ Search

Biomedical subjects

A G Randolph

Publications and source records attributed to A G Randolph.

16 recordsLinked to original sources
PubMed1998

Benefit of heparin in peripheral venous and arterial catheters: systematic review and meta-analysis of randomised controlled trials.

OBJECTIVE: To evaluate the effect of heparin on duration of catheter patency and on prevention of complications associated with use of peripheral venous and arterial catheters. DESIGN: Critical appraisal and meta-analysis of 26 randomised controlled trials that evaluated infusion of heparin intermittently or continuously. Thirteen trials of peripheral venous catheters and two of peripheral arterial catheters met criteria for inclusion. MAIN OUTCOME MEASURES: Data on the populations, interventions, outcomes, and methodological quality. RESULTS: For peripheral venous catheters locked between use flushing with 10 U/ml of heparin instead of normal saline did not reduce the incidence of catheter clotting and phlebitis or improve catheter patency. When heparin was given as a continuous infusion at 1 U/ml the risk of phlebitis decreased (relative risk 0.55; 95% confidence interval 0.39 to 0.77), the duration of patency increased, and infusion failure was reduced (0.88; 0.72 to 1.07). Heparin significantly prolonged duration of patency of radial artery catheters and decreased the risk of clot formation (0.51; 0.42 to 0.61). CONCLUSIONS: Use of intermittent heparin flushes at doses of 10 U/ml in peripheral venous catheters locked between use had no benefit over normal saline flush. Infusion of low dose heparin through a peripheral arterial catheter prolonged the duration of patency but further study is needed to establish its benefit for peripheral venous catheters.

Adolescent↗
PubMed1998

An evidence-based approach to central venous catheter management to prevent catheter-related infection in critically ill patients.

A systematic search of the literature yielded 102 randomized controlled trials of interventions aimed at reducing central venous catheter-related infections in critically ill patients. The process of critically appraising these trials has begun and clinicians have performed meta-analyses of the data in some areas. There are three main components to the production of evidence-based guidelines in this area: identification of effective interventions, comparison of the relative merit of effective interventions aimed at the source of infection, and assessment of the applicability of the evidence to diverse sub-populations of critically ill patients.

Anticoagulants↗
PubMed1998

Prognosis in the intensive care unit: finding accurate and useful estimates for counseling patients.

OBJECTIVES: Counseling critically ill patients and their families about what the future is likely to hold requires accurate prognostic information. Our goal is to teach clinicians how to find and critically appraise prognostic studies that examine homogeneous populations. CLINICAL EXAMPLE: An article describing the outcomes of a group of children who are in a prolonged, persistent vegetative state. RECOMMENDATIONS: The validity of prognostic studies is increased when: a) the sample of patients is representative; b) patients are homogeneous with respect to prognostic risk; c) follow-up is sufficient to minimize the possibility that the missing patients could alter the interpretation of the results; and d) health outcomes are evaluated, using objective and unbiased criteria. The likelihood of these outcomes over time and the precision around these probability estimates should be easily understandable. Before using the results of these studies to counsel patients and families, practitioners should ensure that the patients in the study and their management are similar to the patient in question, and that follow-up of the subjects is sufficiently long. CONCLUSIONS: The criteria outlined in this article may assist clinicians in interpreting articles describing the prognosis of patients with similar clinical conditions.

Adolescent↗
PubMed1998

Understanding articles comparing outcomes among intensive care units to rate quality of care. Evidence Based Medicine in Critical Care Group.

OBJECTIVES: Comparisons of risk-adjusted outcomes among intensive care units (ICUs) is a relatively new but rapidly expanding area of ICU health services research. By investigating those factors that lead ICUs to have patient outcomes that differ from the average, the overall quality of care across ICUs may be improved. Our goal is to teach clinicians how to evaluate these types of articles. CLINICAL EXAMPLE: An article describing the development and application of an index used to assess the clinical performance and cost-effectiveness of 25 ICUs. RECOMMENDATIONS: Valid comparisons of the outcomes among ICUs are made when: a) the outcome measures are accurate and comprehensive; b) the ICUs being compared serve similar patients; c) the sampling of patients is sufficient and unbiased; d) appropriate risk adjustment is undertaken by applying a valid model to reliably collected data; and e) the comparisons focus on care delivered in the ICU. To evaluate the results of the study, clinicians must evaluate how confident they are that the outcome differences being described are clinically important. Before changes in ICU policy are made based on these outcome differences, it is important to clarify which factors might have resulted in these extreme outcomes and whether these results are applicable in the ICU population that will see the impact of the changes. CONCLUSION: The potential for misinterpretation of outcome performance ratings may decrease if articles describing outcome differences are evaluated, using the criteria outlined in this article.

Evidence-Based Medicine↗
PubMed1998

Tunneling short-term central venous catheters to prevent catheter-related infection: a meta-analysis of randomized, controlled trials.

OBJECTIVE: To evaluate the efficacy of tunneling short-term central venous catheters to prevent catheter-related infections. DATA SOURCES: MEDLINE, EMBASE, conference proceedings, citation review of relevant primary and review articles, personal files, and contact with expert informants. STUDY SELECTION: From a pool of 225 randomized, controlled trials of venous and arterial catheter management, we identified 12 relevant trials and included seven of these trials in the analysis. DATA EXTRACTION: In duplicate, independently, we abstracted data on the population, intervention, outcomes, and methodologic quality. DATA SYNTHESIS: Tunneling decreased bacterial colonization of the catheter by 39% (relative risk of 0.61; 95% confidence interval [CI] of 0.39 to 0.95) and decreased catheter-related sepsis with bacteriologic confirmation by 44% (relative risk of 0.56; 95% CI of 0.31 to 1) in comparison with standard placement. The majority of the benefit in the decreased rate of catheter-sepsis came from one trial at the internal jugular site (relative risk of 0.30, 95% CI of 0.10 to 0.89) and the reduction in risk was not significant when the data from five subclavian catheter trials were pooled (relative risk of 0.71, 95% CI of 0.36 to 1.43). Tunneling was not associated with increased risk of mechanical complications from placement or technical difficulties during placement. However, this outcome was not rigorously evaluated. CONCLUSIONS: Tunneling decreases central venous catheter-related infections. However, current evidence does not support routine tunneling until its efficacy is evaluated at different placement sites and relative to other interventions.

Bacteremia↗
PubMed1998

Benefit of heparin in central venous and pulmonary artery catheters: a meta-analysis of randomized controlled trials.

OBJECTIVE: To evaluate the effect of heparin on thrombus formation and infection associated with use of central venous and pulmonary artery catheters. DATA SOURCES: We used MEDLINE, EMBASE, citation review of relevant primary and review articles, personal files, and contact with expert informants. STUDY SELECTION: Fourteen randomized controlled trials evaluating prophylactic doses of heparin or heparin bonding were included. DATA EXTRACTION: In duplicate, independently, we abstracted data on the population, intervention, outcome, and methodologic quality. DATA SYNTHESIS: Prophylactic heparin decreases catheter-related venous thrombosis (relative risk [RR], 0.43; 95% confidence interval [CI], 0.23, 0.78) and bacterial colonization (RR, 0.18; 95% CI, 0.06, 0.60) of central venous catheters and may decrease catheter-related bacteremia (RR, 0.26; 95% CI, 0.07, 1.03). Heparin bonding decreases the risk of pulmonary artery catheter clot formation within 24 h (RR, 0.08; 95% CI, 0.02, 0.37). CONCLUSIONS: Heparin administration effectively reduces thrombus formation and may reduce catheter-related infections in patients who have central venous and pulmonary artery catheters in place. Cost-effectiveness comparisons of unfractionated heparin, low molecular weight heparin, and warfarin are needed.

Adult↗
PubMed1997

Factors explaining variability among caregivers in the intent to restrict life-support interventions in a pediatric intensive care unit.

OBJECTIVE: To explore patient-related factors which influence the decisions of pediatric intensive care unit (ICU) caregivers to restrict life-support interventions. DESIGN: Cross-sectional survey. SETTING: A university-affiliated pediatric ICU. SUBJECTS: All physicians and nurses caring for oncology or cardiology ICU patients. INTERVENTIONS: Seven patient characteristics were systematically presented in 16 theoretical case scenarios. MEASUREMENTS AND MAIN RESULTS: Individual linear regression models were constructed for each participant by calculating the importance caregivers placed on seven patient characteristics when deciding about starting intravenous vasopressors, performing chest compressions, and withdrawing life support. We compared the numerical and descriptive (very low, low, moderate, high) probability of survival. We surveyed 86 caregivers and 56 (65%) responded. The most important factors influencing decisions were family preferences (76% of decisions), followed by probability of survival (50%), and functional status (47%). There was marked variability among respondents in 38 (79%)/48 of the questions; 20% to 50% of caregivers chose opposing directions of patient management when they were asked to indicate the likelihood that they would perform a specific life-support intervention. The same term was never used by all respondents to describe the probability of survival for a scenario. CONCLUSION: Critically ill children and their families could face markedly different attitudes about the restriction of life-support interventions, depending on which nurses and physicians are involved in their care.

Activities of Daily Living↗
PubMed1996

Ribavirin for respiratory syncytial virus lower respiratory tract infection. A systematic overview.

OBJECTIVE: To systematically review the evidence evaluating the efficacy of aerosolized ribavirin for the treatment of infants with respiratory syncytial virus lower respiratory tract infection. DESIGN: A computerized search of MEDLINE from 1975 to the present, a review of the reference lists of each retrieved article, and contact with experts. PATIENTS: infants with documented respiratory syncytial virus lower respiratory tract infection who were the subjects of 8 double-blind randomized placebo-controlled trials. METHODS: Two independent reviewers assessed study quality and extracted data on the study populations, the drug regimens, and clinically relevant outcome measurements. RESULTS: Ribavirin does not significantly reduce mortality rate (relative risk [RR] = 0.42, 95% confidence interval [CI] = 0.13, 1.44) or lower the probability of respiratory deterioration (RR = 0.42, 95% CI = 0.16, 1.34) when meta-analysis is used to pool the outcomes of 3 trials, although strong trends in the direction of benefit are present. No study found ribavirin to shorten length of hospitalization. Results on length of ventilation and oxygen supplementation are conflicting. CONCLUSIONS: Use of ribavirin in infants with respiratory syncytial virus lower respiratory tract infection is not supported by evidence of significant benefit. However, previous studies lack sufficient power to rule out a potential reduction in mortality rate or respiratory deterioration. A large randomized controlled trial of ribavirin for ventilated and other high-risk patients is needed.

Antiviral Agents↗
PubMed1996

Acyclovir prophylaxis in late pregnancy to prevent neonatal herpes: a cost-effectiveness analysis.

OBJECTIVE: To compare the cost-effectiveness of oral acyclovir prophylaxis in late pregnancy to the current strategy of cesarean delivery for genital herpes lesions in the prevention of neonatal herpes transmission from mothers with recurrent genital infections. METHODS: Decision analysis was used to evaluate the clinical outcomes and direct costs of a prevention program from the health care payer's perspective. Probabilities were obtained from the literature and experts. Cost data were based on hospital costs and a cohort of herpes-infected neonates. RESULTS: Acyclovir prophylaxis during late pregnancy followed by cesarean delivery for genital lesions at delivery in women with recurrent genital herpes requires 1818 women to follow this strategy to prevent one neonatal infection and 7.4 women to take acyclovir to prevent one outbreak of genital herpes at delivery, at a cost (above no intervention) of over $493,000 per neonatal infection prevented, $1.1 million per neonatal death or disability prevented, and $1444 per maternal outbreak prevented. Cesarean delivery for genital herpes lesions requires 386 women with recurrent herpes to undergo cesareans to prevent one neonatal infection, at a cost of more than $1.3 million per neonatal infection prevented and more than $3 million per neonatal death or disability prevented. If acyclovir is given and herpes lesions still occur, the incremental cost of requiring cesarean delivery for these women over vaginal delivery with culture and follow-up of exposed infants is more than $1.4 million per neonatal infection prevented. CONCLUSION: Oral acyclovir prophylaxis in late pregnancy for women with recurrent genital herpes is more cost-effective than the current strategy of cesarean delivery for all women presenting with genital herpes lesions.

Acyclovir↗
PubMed1996

Ultrasound guidance for placement of central venous catheters: a meta-analysis of the literature.

OBJECTIVE: To evaluate the effect of real-time ultrasound guidance using a regular or Doppler ultrasound technique for placement of central venous catheters. DATA SOURCES: We searched for published and unpublished research using MEDLINE, citation review of relevant primary and review articles, conference abstracts, personal files, and contact with expert informants. STUDY SELECTION: From a pool of 208 randomized, controlled trials of venous and arterial catheter management, eight published randomized, controlled trials were identified. DATA EXTRACTION: In duplicate, independently, we abstracted data on the population, intervention, outcome, and methodologic quality. DATA SYNTHESIS: Ultrasound guidance significantly decreases internal jugular and subclavian catheter placement failure (relative risk 0.32; 95% confidence interval 0.18 to 0.55), decreases complications during catheter placement (relative risk 0.22; 95% confidence interval 0.10 to 0.45), and decreases the need for multiple catheter placement attempts (relative risk 0.60; 95% confidence interval 0.45 to 0.79) when compared with the standard landmark placement technique. CONCLUSIONS: When used for vessel location and catheter placement real-time, ultrasound guidance or Doppler ultrasound guidance improves success rates and decreases the complications associated with internal jugular and subclavian venous catheter placement.

Catheterization, Central Venous↗
PubMed1996

Testing and validation of computerized decision support systems.

Systematic, through testing of decision support systems (DSSs) prior to release to general users is a critical aspect of high quality software design. Omission of this step may lead to the dangerous, and potentially fatal, condition of relying on a system with outputs of uncertain quality. Thorough testing requires a great deal of effort and is a difficult job because tools necessary to facilitate testing are not well developed. Testing is a job ill-suited to humans because it requires tireless attention to a large number of details. For these reasons, the majority of DSSs available are probably not well tested prior to release. We have successfully implemented a software design and testing plan which has helped us meet our goal of continuously improving the quality of our DSS software prior to release. While requiring large amounts of effort, we feel that the process of documenting and standardizing our testing methods are important steps toward meeting recognized national and international quality standards. Our testing methodology includes both functional and structural testing and requires input from all levels of development. Our system does not focus solely on meeting design requirements but also addresses the robustness of the system and the completeness of testing.

Artificial Intelligence↗
PubMed1993

Cesarean delivery for women presenting with genital herpes lesions. Efficacy, risks, and costs.

OBJECTIVE: To assess the effect of cesarean delivery on neonatal and maternal morbidity and mortality and their associated costs for two populations of women presenting with genital herpes lesions at delivery: those with and those without a history of genital herpes. DATA SOURCES: MEDLINE (search for herpes simplex virus and neonatal, cesarean, and mortality) and recognized experts. DATA EXTRACTION: The quality of the overall data used for baseline values was graded using a predetermined scale. RESULTS: The practice of cesarean delivery for women with a history of genital herpes lesions that recur at delivery results in more than 1580 excess cesarean deliveries performed for every poor neonatal outcome prevented, a cost per neonatal herpes case averted of $2.5 million and a cost per quality-adjusted life-year gained of $203,000. For these women, lowering the efficacy of cesarean delivery or the herpes simplex virus vertical transmission rate could result in maternal deaths outnumbering neonatal deaths prevented. In contrast, cesarean delivery for women with no history of genital herpes simplex virus who have lesions at delivery has low maternal costs per neonatal benefit and saves money. CONCLUSIONS: Women who present with their first clinical episode of genital herpes at delivery should have a cesarean section performed. However, the current practice of cesarean delivery for women with a history of genital herpes lesions that recur at delivery results in high maternal morbidity and mortality at substantial financial expense, underscoring the urgency of examining alternative management strategies.

Cesarean Section↗
PubMed1990

Screening for Chlamydia trachomatis in adolescent males: a cost-based decision analysis.

To evaluate the cost and benefits of screening tests for Chlamydia trachomatis in adolescent males, we developed a decision analysis model and compared the leukocyte esterase urine dipstick test with culture, with direct-smear fluorescent antibody (DFA), and with the option of no screening (no treatment). The leukocyte esterase test has the lowest average cost-per-cure ($51) compared with direct-smear fluorescent antibody ($192) and culture ($414). Compared with the DFA, we estimate that the leukocyte esterase test saves over $9,727 per cohort of 1,000 sexually active adolescent males screened. Sensitivity analyses show the leukocyte esterase test results in a lower cost-per-cure and lower overall costs (per cohort) than culture and direct-smear fluorescent antibody at any prevalence of C. trachomatis infection, and lower overall costs (per cohort) than no screening at prevalences above 21 percent.

Adolescent↗