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G Guyatt

Publications and source records attributed to G Guyatt.

At least 37 records · Page 2Linked to original sources
PubMed2001

Health-related quality of life in chronic liver disease: the impact of type and severity of disease.

OBJECTIVE: The type and severity of chronic liver disease may have different effects on health-related quality of life (HRQL). The aim of our study was to determine whether HRQL in patients with chronic liver disease differs by type and severity of disease and to identify which clinical and physiological factors affect this impairment. METHODS: In this study, HRQL was measured with a generic (Short Form 36) and a liver disease-specific (Chronic Liver Disease Questionnaire) questionnaire. Clinical, demographic, and laboratory data were collected at office visits. Patient's HRQL scores were compared with the published norms and to the chronically ill populations. A total of 353 patients (mean age 50 yr, 51% men) with chronic liver disease, either viral disease (hepatitis B and C), cholestatic disease (primary biliary cirrhosis or primary sclerosing cholangitis), or hepatocellular disease were enrolled in the study. RESULTS: In general, HRQL in patients with chronic liver disease was lower than the normal population and was similar to that of patients with chronic obstructive pulmonary disease or congestive heart failure. In cirrhotic patients, some dimensions of HRQL were less impaired in patients with cholestatic disease than in those with hepatocellular diseases. More severe disease (higher Child's class) was associated with a lower Chronic Liver Disease Questionnaire score and the Short Form 36's physical component summary scores. Older age had a weak negative association with the physical aspects of HRQL. CONCLUSIONS: We conclude that chronic liver disease substantially reduces HRQL, and this impact does not differ markedly by type of disease. Older age and measures of disease severity were associated with poorer HRQL.

Age Factors↗
PubMed2001

Regular versus as-needed short-acting inhaled beta-agonist therapy for chronic obstructive pulmonary disease.

Regular short-acting inhaled beta-agonist therapy is of uncertain benefit in patients with chronic obstructive pulmonary disease (COPD). We conducted a randomized, concealed, double-blind, placebo-controlled crossover trial in two periods, each of 3-mo duration, involving 53 patients with a smoking history of > 20 pack-years, an FEV1 of < 70% predicted, and an FEV1/VC ratio of < 0.7 after inhalation of 200 microg albuterol. All patients received regular ipratropium bromide at 20 microg per puff in 2 puffs four times daily, beclomethasone at 250 microg per puff or equivalent corticosteroid in 2 puffs twice daily, and open-label inhaled albuterol as needed. Interventional therapy consisted of regular inhaled albuterol (100 microg per puff, in 2 puffs four times daily) versus placebo. Patients used twice as much active albuterol in the regular use period (mean: 8.07 puffs of coded and 4.68 puffs of open-label medication; total: 12.75 puffs daily) than during the as-needed period (mean: 6.34 puffs of open-label albuterol daily). Despite greater beta-agonist use, patients showed similar results during treatment and control periods for all outcomes. Differences between active and placebo periods were: FEV1: -0.04 L (95% confidence interval [CI]: -0.09 to 0.01 L); slow vital capacity: 0.04 L (95% CI: -0.12 to 0.20 L); 6-min walk test distance: -3.1 m (95% CI: -16.8 to 10.5 m); and Chronic Respiratory Questionnaire scores for dyspnea: 0.02 (95% CI: -0.13 to 0.16); fatigue: -0.02 (95% CI: -0.25 to 0.20); mastery: 0.01 (95% CI: -0.20 to 0.24); and emotional function: 0.02 (95% CI: -0.20 to 0.24). We found that in patients with COPD, use of regular short-acting inhaled beta-agonists resulted in twice as much beta-agonist use without physiologic or clinical benefit as did use on an as-needed basis.

Administration, Inhalation↗
PubMed2001

Grades of recommendation for antithrombotic agents.

The strength of any recommendation depends on two factors: the trade-off between benefits and risks, and the strength of the methodology that leads us to estimates of the treatment effect. The framework that we used for this conference captures these factors. We grade the trade-off between benefits and risks in two categories: (1) the trade-off is clear enough that most patients, despite differences in values, would make the same choice; and (2) the trade-off is less clear, and each patient's values will likely lead to different choices. We grade methodologic strength in three categories: (1) randomized trials, ideally summarized in a meta-analysis, that show consistent results; (2) randomized trials with inconsistent results; and (3)observational studies. The framework summarized in Table 1 therefore generates recommendations from the very strong (1A: benefit/risk clear, methods strong) to the very weak (2C: benefit/risk questionable, methods weak). Whatever the grade of recommendation, clinicians must bring their judgment considering local and individual patient circumstances, and patient values, to bear in making individual decisions. In general, however, they should place progressively greater weight on expert recommendations as they move from 2C to 1A.

Fibrinolytic Agents↗
PubMed2001

Predicting success in weaning from mechanical ventilation.

We identified 65 observational studies of weaning predictors that had been reported in 70 publications. After grouping predictors with similar names but different thresholds, the following predictors met our relevance criteria: heterogeneous populations, 51; COPD patients, 21; and cardiovascular ICU patients, 45. Many variables were of no use in predicting the results of weaning. Moreover, few variables had been studied in > 50 patients or had results presented to generate estimates of predictive power. For stepwise reductions in mechanical support, the most promising predictors were a rapid shallow breathing index (RSBI) < 65 breaths/min/L (measured using the ventilator settings that were in effect at the time that the prediction was made) and a pressure time product < 275 cm H2O/L/s. The pooled likelihood ratios (LRs) were 1.1 (95% confidence interval [CI], 0.95 to 1.28) for a respiratory rate [RR] of < 38 breaths/min and 0.32 (95% CI, 0.06 to 1.71) for an RR of > 38 breaths/min, which indicate that an RR of < 38 breaths/min leaves the probability of successful weaning virtually unchanged but that a value of > 38 breaths/min leads to a small reduction in the probability of success in weaning the level of mechanical support. For trials of unassisted breathing, the most promising weaning predictors include the following: RR; RSBI; a product of RSBI and occlusion pressure < 450 cm H2O breaths/min/L; maximal inspiratory pressure (PImax) < 20 cm H2O; and a knowledge-based system for adjusting pressure support. Pooled results for the power of a positive test result for both RR and RSBI were limited (highest LR, 2.23), while the power of a negative test result was substantial (ie, LR, 0.09 to 0.23). Summary data suggest a similar predictive power for RR and RSBI. In the prediction of successful extubation, an RR of < 38 breaths/min (sensitivity, 88%; specificity, 47%), an RSBI < 100 or 105 breaths/min/L (sensitivity, 65 to 96%; specificity, 0 to 73%), PImax, and APACHE (acute physiology and chronic health evaluation) II scores that are obtained at hospital admission appear to be the most promising. After pooling, two variables appeared to have some value. An RR of > 38 breaths/min and an RSBI of > 100 breaths/min/L appear to reduce the probability of successful extubation, and PImax < 0.3, for which the pooled LR is 2.23 (95% CI, 1.15 to 4.34), appears to marginally increase the likelihood of successful extubation. Judging by areas under the receiver operator curve for all variables, none of these variables demonstrate more than modest accuracy in predicting weaning outcome. Why do most of these tests perform so poorly? The likely explanation is that clinicians have already considered the results when they choose patients for trials of weaning.

APACHE↗
PubMed2001

Trials comparing alternative weaning modes and discontinuation assessments.

We identified 16 randomized controlled trials (RCTs) of methods for weaning patients from mechanical ventilation, 8 of which were trials of discontinuation assessment strategies, 5 of which were trials of stepwise reduction in mechanical ventilatory support, and 3 of which were trials comparing alternative ventilation modes for weaning periods lasting < 48 h. We found that different thresholds for deciding when a patient is ready for a trial of spontaneous breathing, different criteria for a successful trial, and different thresholds for extubation may overwhelm the impact of alternative ventilation strategies. Nevertheless, the results of these studies suggest the possibility that multiple daily T-piece weaning or pressure support may be superior to synchronized intermittent mandatory ventilation. Other RCTs suggest that early extubation with the back-up institution of noninvasive positive-pressure ventilation as needed may be a useful strategy in selected patients.

Evidence-Based Medicine↗
PubMed2001

Trials of miscellaneous interventions to wean from mechanical ventilation.

We found eight randomized controlled trials (RCTs) of miscellaneous interventions that were designed to facilitate the process of weaning from mechanical ventilation. The two RCTs of high-fat/low-carbohydrate enteral nutrition found favorable physiologic effects on CO2 production and respiratory quotient, rendering this type of nutrition potentially useful in patients with impaired ventilatory reserve; however, no conclusions can be made about the outcomes of the duration of ventilation and weaning success. The two RCTs of postextubation use of noninvasive ventilation are conflicting, showing potential short-term physiologic benefit in one study, but no benefit in terms of reintubation rates or other morbidity. These RCTs are less promising than other applications of noninvasive ventilation such as those in patients with COPD exacerbations. One RCT showed no improvement in success of weaning with exogenous growth hormone administration. In the setting of very frequent baseline blood gas analyses, one RCT of oximetry and capnography was associated with significantly fewer blood gas analyses. Biofeedback to enhance safe and rapid weaning showed a dramatically lower duration of ventilation in one RCT that did not report the weaning methods used. One RCT of preextubation acupuncture showed lower rates of laryngospasm in the acupuncture group. Overall, these studies were underpowered for clinically important outcomes. Multidisciplinary, patient-centered, holistic, and non-pulmonary approaches to weaning may provide additional safe, effective adjunctive methods of hastening liberation from mechanical ventilation.

Acupuncture↗
PubMed2001

Trials comparing early vs late extubation following cardiovascular surgery.

We identified 10 randomized trials that compared alternative management approaches to patient care during and following cardiovascular surgery. One overall strategy involved a modification of anesthesia, in particular, a reduction in the dosage of fentanyl and benzodiazepine or the substitution of fentanyl for propofol (five randomized controlled trials [RCTs]). Pooled results show a shorter duration of ventilation (7 h) and a shorter duration of hospital stay (approximately 1 day) associated with lower anesthetic doses. The second strategy involved early vs late extubation once patients were admitted to the ICU (five RCTs). Pooled results show a shorter duration of ventilation (13 h) and a shorter duration of ICU stay (half a day) associated with early extubation. An additional 8 nonrandomized trials had findings that were consistent with the 10 RCTs. Reintubation, complications, and mortality rates were too low to draw conclusions about these outcomes. Overall, these studies indicate that anesthetic, sedation, and early-extubation strategies in selected cardiac surgery patients are associated with a shorter duration of mechanical ventilation and shorter lengths of ICU and hospital stays.

Cardiac Surgical Procedures↗
PubMed2000

Using and understanding sedation scoring systems: a systematic review.

OBJECTIVE: To systematically review instruments for measuring the level and effectiveness of sedation in adult and pediatric ICU patients. STUDY IDENTIFICATION: We searched MEDLINE, EMBASE, the Cochrane Library and reference lists of the relevant articles. We selected studies if the sedation instrument reported items related to consciousness and one or more additional items related to the effectiveness or side effects of sedation. DATA ABSTRACTION: We extracted data on the description of the instrument and on their measurement properties (internal consistency, reliability, validity and responsiveness). RESULTS: We identified 25 studies describing relevant sedation instruments. In addition to the level of consciousness, agitation and synchrony with the ventilator were the most frequently assessed aspects of sedation. Among the 25 instruments, one developed in pediatric ICU patients (the Comfort Scale), and 3 developed in adult ICU patients (the Ramsay scale, the Sedation-Agitation-Scale and the Motor Activity Assessment Scale), were tested for both reliability and validity. None of these instruments were tested for their ability to detect change in sedation status over time (responsiveness). CONCLUSION: Many instruments have been used to measure sedation effectiveness in ICU patients. However, few of them exhibit satisfactory clinimetric properties. To help clinicians assess sedation at the bedside, to aid readers critically appraise the growing number of sedation studies in the ICU literature, and to inform the design of future investigations, additional information about the measurement properties of sedation effectiveness instruments is needed.

Adult↗
PubMed2000

Impact of liver transplantation on health-related quality of life.

This study is designed to measure the impact of orthotopic liver transplantation (OLT) on patients' health-related quality of life. Two types of health-related quality-of-life questionnaires were administered at baseline and after OLT: generic (Medical Outcomes Study Short Form 36) and liver specific (Chronic Liver Disease Questionnaire). We also recorded clinical, demographic, and laboratory data. Pre-OLT scores of liver transplant candidates were compared with those of the general population and patients with congestive heart failure (CHF) and chronic obstructive pulmonary disease (COPD). Thirty-seven liver transplant candidates were evaluated: 25 men and 12 women; age, 50.2 +/- 12 years; Child's class A, 3 patients; class B, 30 patients; class C, 4 patients; and galactose elimination capacity, 277 +/- 81. Health-related quality-of-life scores for patients awaiting liver transplants were significantly lower than those for patients with COPD and CHF and those in the general population. Sex and cause of liver disease did not affect the scores. There was a weak but significant inverse correlation between some aspects of health-related quality of life and both age (r = -0.31 to -0.34) and worsening of the Child-Pugh score (r = -0.32 to -0.43). All measured aspects of health-related quality of life significantly improved after OLT, and mental health scores were indistinguishable from the population norms. Similar improvements were evident in physical and disease-specific aspects of health-related quality of life, but some residual dysfunction persisted.

Female↗
PubMed2000

The use of a simulated environment (easy street) to retrain independent living skills in elderly persons: a randomized controlled trial.

BACKGROUND: Older adults who receive training for functional skills in contextually appropriate environments may show greater functional improvement than persons trained in a traditional environment. Functionally limited older adults receiving training in contextually appropriate environments (simulated home and community settings) may show greater improvement in activities of daily living (ADL) than persons trained in a traditional manner. METHODS: Eighty-eight patients from a day hospital, aged 65 years or older, were randomized to either receive rehabilitation in a simulated environment (Easy Street) or in a gymnasium setting. Rehabilitation focused on retraining functional skills in a contextually appropriate environment (Easy Street) or in a traditional setting (gymnasium) using motor learning principles for a period of 16 weeks. Outcome measures included the Structured Assessment of Instrumental Living Skills (SAILS), a performance measure with criterion and timed components; a self-report health status questionnaire, the Short Form-36 (SF-36); and the patient-orientated goal-directed Canadian Occupational Performance Measure (COPM). RESULTS: There were no group differences on any of the outcome measures: SAILS (p = .3); the SF-36 physical (p = .83) and mental (p = .51); and the COPM performance scale (p = .94) and satisfaction scale (p = .40). CONCLUSIONS: Although we have not excluded benefits of contextually appropriate rehabilitation environments with different intervention approaches, at different stages of rehabilitation or with patients at higher functional levels, our results suggest the appropriateness of a moratorium on these expensive interventions pending demonstration of clear positive effects determined from further study.

Activities of Daily Living↗
PubMed2000

Cholestatic liver diseases and health-related quality of life.

OBJECTIVE: Symptoms associated with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) negatively affect health-related quality of life (HRQL). The aim of this study was to measure HRQL in patients with chronic cholestatic liver diseases and to determine factors associated with more severe impairment. METHODS: We conducted a cross-sectional study in which we documented patients' demographic and clinical characteristics, and measured their HRQL using the Short Form-36 and Chronic Liver Disease Questionnaire. We assessed the association of HRQL impairment with disease severity (Child's-Pugh class and Mayo PBC Risk Score) and compared patients' HRQL with those of a healthy population, and patients with congestive heart failure, chronic obstructive pulmonary disease, and diabetes. RESULTS: One hundred and four patients with PBC and PSC participated, of whom 73% were women, with an average age of 55+/-12 yr. Of these patients, 61% had cirrhosis (37% Child's A, 23% Child's B, and 2% Child's C). Patients with cholestatic liver disease showed more HRQL impairment than the healthy population and were similar to patients with other chronic conditions. Additionally, patients who experienced severe itching showed profound HRQL impairment. In patients with PBC, Physical Component Summary (PCS) scores of the SF-36 and Chronic Liver Disease Questionnaire (CLDQ) scores fell from noncirrhotic to Child's A to Child's B/C and with worsening Mayo PBC Risk Scores. No other clinicodemographic data were associated with patients' well-being. CONCLUSIONS: Patients with cholestatic liver disease (PBC and PSC) showed substantial impairment of HRQL, which is further affected by worsening disease severity. Disease-specific measures were better able to discriminate patients with varying severities.

Analysis of Variance↗
PubMed1999

Diagnosis of thyroid disease in hospitalized patients: a systematic review.

BACKGROUND: The optimal approach for the diagnosis of hypothyroidism and hyperthyroidism in hospitalized patients is controversial. OBJECTIVES: To estimate the prevalence of undiagnosed thyroid disease among inpatients, review the usefulness of clinical signs and symptoms, and elucidate the characteristics of the sensitive thyrotropin (thyroid-stimulating hormone) (sTSH) test in this population. METHODS: We undertook a systematic review of the literature by conducting a MEDLINE search covering January 1966 through December 1996. Searching was conducted in duplicate and independently. Specific inclusion and exclusion criteria were predetermined. RESULTS: Prevalence of thyroid disease among inpatients is approximately 1% to 2% and is similar to the outpatient population. Absence of clinical features of thyroid disease lowers the pretest likelihood and makes screening even less useful. Presence of clinical features, especially those specific for thyroid disease (eg, goiter), may increase the pretest likelihood and increase the yield of testing. Acute illness reduces the specificity of second-generation sTSH tests for thyroid disease. The positive likelihood ratio associated with an abnormal sTSH test result in ill inpatients is about 10 compared with about 100 in outpatients. CONCLUSION: In unselected general medical, geriatric, or psychiatric inpatient populations, sTSH testing provides a low yield of true-positive and many false-positive results.

Diagnosis, Differential↗
PubMed1999

Development of a disease specific questionnaire to measure health related quality of life in patients with chronic liver disease.

BACKGROUND AND AIMS: To develop and assess a disease specific instrument for measuring health related quality of life (HRQL) in patients with chronic liver disease (CLD). METHODS: Based on responses from 60 patients with chronic liver disease, from 20 liver experts, and from a Medline search of the literature, items potentially affecting the HRQL of these patients were identified. A separate sample of 75 patients identified which items they found problematic and rated their importance. Results were explored using factor analysis; domains were chosen and items placed within domains. Redundant questions were eliminated and the final questionnaire was pretested in 10 patients. Using this instrument, HRQL was assessed in a further 133 patients with various types and stages of liver disease. RESULTS: Patients, experts, and the literature search identified 156 items of potential importance. Of these, 35 proved important to over 50% of 75 respondents in the item reduction sample. The factor analysis suggested six domains. After eliminating redundancies, the Chronic Liver Disease Questionnaire (CLDQ) included 29 items in the following domains: fatigue, activity, emotional function, abdominal symptoms, systemic symptoms, and worry. In pretesting, patients found the CLDQ clear and easy to complete in 10 minutes. In another 133 patients, the CLDQ showed a gradient between patients without cirrhosis, Child's A cirrhosis, and those with Child's B or C cirrhosis. CLDQ has evidence for moderate reliability at six months and seems to be responsive. CONCLUSION: The CLDQ is short, easy to administer, produces both a summary score and domain scores, and correlates with the severity of liver disease.

Analysis of Variance↗