George Wells

The OPALS Major Trauma Study: impact of advanced life-support on survival and morbidity.

Background: To date, the benefit of prehospital advanced life-support programs on trauma-related mortality and morbidity has not been established Methods: The Ontario Prehospital Advanced Life Support (OPALS) Major Trauma Study was a before–after systemwide controlled clinical trial conducted in 17 cities. We enrolled adult patients who had experienced major trauma in a basic life-support phase and a subsequent advanced life-support phase (during which paramedics were able to perform endotracheal intubation and administer fluids and drugs intravenously). The primary outcome was survival to hospital discharge. Results: Among the 2867 patients enrolled in the basic life-support (n = 1373) and advanced life-support (n = 1494) phases, characteristics were similar, including mean age (44.8 v. 47.5 years), frequency of blunt injury (92.0% v. 91.4%), median injury severity score (24 v. 22) and percentage of patients with Glasgow Coma Scale score less than 9 (27.2% v. 22.1%). Survival did not differ overall (81.1% among patients in the advanced life-support phase v. 81.8% among those in the basic life-support phase; p = 0.65). Among patients with Glasgow Coma Scale score less than 9, survival was lower among those in the advanced life-support phase (50.9% v. 60.0%; p = 0.02). The adjusted odds of death for the advanced life-support v. basic life-support phases were nonsignificant (1.2, 95% confidence interval 0.9–1.7; p = 0.16). Interpretation: The OPALS Major Trauma Study showed that systemwide implementation of full advanced life-support programs did not decrease mortality or morbidity for major trauma patients. We also found that during the advanced life-support phase, mortality was greater among patients with Glasgow Coma Scale scores less than 9. We believe that emergency medical services should carefully re-evaluate the indications for and application of prehospital advanced life-support measures for patients who have experienced major trauma.

Preventing perineal trauma during childbirth: a systematic review.

Abstract Objective: To review systematically techniques proposed to prevent perineal trauma during childbirth and meta-analyze the evidence of their efficacy from randomized controlled trials. Data Sources: MEDLINE (1966–1999), the Cochrane Library (1999 Issue 1), and the Cochrane Collaboration: Pregnancy and Childbirth Database (1995); and reference lists from articles identified. Search terms included childbirth or pregnancy or delivery, and perineum, episiotomy, perineal massage, obstetric forceps, vacuum extraction, labor stage–second. No language or study-type constraints were imposed. Study Selection: Randomized controlled trials (RCTs) of interventions affecting perineal trauma were reviewed. If no RCTs were available, nonrandomized research designs such as cohort studies were included. Studies were selected by examination of titles and abstracts of more than 1500 articles, followed by analysis of the methods sections of studies that appeared to be RCTs. Integration and Results: Eligible studies used random or quasirandom allocation of an intervention of interest and reported perineal outcomes. Further exclusions were based on failure to report results by intention to treat, or incomplete or internally inconsistent reporting of perineal outcomes. Final selection of studies and data extraction was by consensus of the first two authors. Data from trials that evaluated similar interventions were combined using a random effects model to determine weighted estimate of risk difference and number needed to treat. Effects of sensitivity analysis and quality scoring were examined. Results indicated good evidence that avoiding episiotomy decreased perineal trauma (absolute risk difference −0.23, 95% confidence interval [CI] −0.35, −0.11). In nulliparas, perineal massage during the weeks before giving birth also protected against perineal trauma (risk difference −0.08, CI −0.12, −0.04). Vacuum extraction (risk difference −0.06, CI −0.10, −0.02) and spontaneous birth (−0.11, 95% CI −0.18, −0.04) caused less anal sphincter trauma than forceps delivery. The mother’s position during the second stage has little influence on perineal trauma (supported upright versus recumbent: risk difference 0.02, 95% CI −0.05, 0.09). Conclusion: Factors shown to increase perineal integrity include avoiding episiotomy, spontaneous or vacuum-assisted rather than forceps birth, and in nulliparas, perineal massage during the weeks before childbirth. Second-stage position has little effect. Further information on techniques to protect the perineum during spontaneous delivery is sorely needed.

Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhage: prospective cohort study

Objective To measure the sensitivity of modern third generation computed tomography in emergency patients being evaluated for possible subarachnoid haemorrhage, especially when carried out within six hours of headache onset. Design Prospective cohort study. Setting 11 tertiary care emergency departments across Canada, 2000-9. Participants Neurologically intact adults with a new acute headache peaking in intensity within one hour of onset in whom a computed tomography was ordered by the treating physician to rule out subarachnoid haemorrhage. Main outcome measures Subarachnoid haemorrhage was defined by any of subarachnoid blood on computed tomography, xanthochromia in cerebrospinal fluid, or any red blood cells in final tube of cerebrospinal fluid collected with positive results on cerebral angiography. Results Of the 3132 patients enrolled (mean age 45.1, 2571 (82.1%) with worst headache ever), 240 had subarachnoid haemorrhage (7.7%). The sensitivity of computed tomography overall for subarachnoid haemorrhage was 92.9% (95% confidence interval 89.0% to 95.5%), the specificity was 100% (99.9% to 100%), the negative predictive value was 99.4% (99.1% to 99.6%), and the positive predictive value was 100% (98.3% to 100%). For the 953 patients scanned within six hours of headache onset, all 121 patients with subarachnoid haemorrhage were identified by computed tomography, yielding a sensitivity of 100% (97.0% to 100.0%), specificity of 100% (99.5% to 100%), negative predictive value of 100% (99.5% to 100%), and positive predictive value of 100% (96.9% to 100%). Conclusion Modern third generation computed tomography is extremely sensitive in identifying subarachnoid haemorrhage when it is carried out within six hours of headache onset and interpreted by a qualified radiologist.

Clinical improvement as reflected in measures of function and health‐related quality of life following treatment with leflunomide compared with methotrexate in patients with rheumatoid arthritis: Sensitivity and relative efficiency to detect a treatment effect in a twelve‐month, placebo‐controlled trial

OBJECTIVEnTo examine correlations between clinical improvement as defined by the American College of Rheumatology (ACR) responder analysis and clinical improvement as determined by 4 function and/or health-related quality of life measures, and to estimate the sensitivity and relative efficiency of these measures compared with changes in the tender joint count in patients with rheumatoid arthritis (RA).nnnMETHODSnA 52-week, multicenter, double-blind controlled trial was conducted to compare treatment with leflunomide (n = 182), methotrexate (n = 180), or placebo (n = 118) in patients with active RA. ACR response rates and improvement in scores on the Health Assessment Questionnaire (HAQ), Problem Elicitation Technique (PET), and Medical Outcomes Survey Short Form 36 (SF-36) were compared in 438 of the patients.nnnRESULTSnIn comparing leflunomide with placebo, the patient global assessment, HAQ disability index, and SF-36 bodily pain scale were most responsive to treatment group differences. The modified HAQ (M-HAQ), PET Top 5, SF-36 physical component score, physician global assessment, pain intensity scale, and SF-36 physical functioning scale were more responsive to treatment group differences than was the tender joint count. In comparing methotrexate with placebo, the patient and physician global assessments were most responsive. These 2 measures, as well as the pain intensity scale and the C-reactive protein level, were more responsive to treatment group differences than was the tender joint count, while the SF-36 mental health component score was least responsive. A close correlation between changes in the M-HAQ and HAQ scores indicated that the M-HAQ was similarly responsive to change over time. Improvements in the PET, SF-36 physical component score, bodily pain, and physical functioning scales correlated with the ACR responder status.nnnCONCLUSIONnBoth disease-specific and generic measures of function and health-related quality of life detect improvements in RA patients. Using both types of measures for evaluating therapies will identify discernible changes that are important to patients, and will facilitate comparisons across different disease states.

Ottawa Panel Evidence-Based Clinical Practice Guidelines for Aerobic Fitness Exercises in the Management of Fibromyalgia: Part 1

Background and Purpose: The objective of this study was to create guidelines for the use of aerobic fitness exercises in the management of adult patients (>18 years of age) with fibromyalgia, as defined by the 1990 American College of Rheumatology criteria. Methods: Following Cochrane Collaboration methods, the Ottawa Methods Group found and synthesized evidence from comparative controlled trials and formed the Ottawa Panel, with nominated experts from key stakeholder organizations. The Ottawa Panel then developed criteria for grading the recommendations based on experimental design (I for randomized controlled trials, II for nonrandomized studies) and strength of evidence (A, B, C+, C, D+, D, or D−). From the rigorous literature search, 13 randomized control trials and 3 controlled clinical trials were selected. Statistical analysis was based on Cochrane Collaboration methods. Continuous data were calculated with weighted mean differences between the intervention and control groups, and dichotomous data were analyzed with relative risks. Clinical improvement was calculated using absolute benefit and relative difference in change from baseline. Clinical significance was attained when an improvement of 15% relative to a control was found. Results: There were 24 positive recommendations: 10 grade A, 1 grade B, and 13 grade C+. Of these 24 positive recommendations, only 5 were of clinical benefit. Discussion and Conclusion: The Ottawa Panel recommends aerobic fitness exercises for the management of fibromyalgia as a result of the emerging evidence (grades A, B, and C+, although most trials were rated low quality) shown in the literature.

Implementation of the Canadian C-Spine Rule: prospective 12 centre cluster randomised trial

Objective To evaluate the effectiveness of an active strategy to implement the validated Canadian C-Spine Rule into multiple emergency departments. Design Matched pair cluster randomised trial. Setting University and community emergency departments in Canada. Participants 11u2009824 alert and stable adults presenting with blunt trauma to the head or neck at one of 12 hospitals. Interventions Six hospitals were randomly allocated to the intervention and six to the control. At the intervention sites, active strategies were used to implement the Canadian C-Spine Rule, including education, policy, and real time reminders on radiology requisitions. No specific intervention was introduced to alter the behaviour of doctors requesting cervical spine imaging at the control sites. Main outcome measure Diagnostic imaging rate of the cervical spine during two 12 month before and after periods. Results Patients were balanced between control and intervention sites. From the before to the after periods, the intervention group showed a relative reduction in cervical spine imaging of 12.8% (95% confidence interval 9% to 16%; 61.7% v 53.3%; P=0.01) and the control group a relative increase of 12.5% (7% to 18%; 52.8% v 58.9%; P=0.03). These changes were significant when both groups were compared (P<0.001). No fractures were missed and no adverse outcomes occurred. Conclusions Implementation of the Canadian C-Spine Rule led to a significant decrease in imaging without injuries being missed or patient morbidity. Final imaging rates were much lower at intervention sites than at most US hospitals. Widespread implementation of this rule could lead to reduced healthcare costs and more efficient patient flow in busy emergency departments worldwide. Trial registration Clinical trials NCT00290875.

High risk clinical characteristics for subarachnoid haemorrhage in patients with acute headache: prospective cohort study

Objective To identify high risk clinical characteristics for subarachnoid haemorrhage in neurologically intact patients with headache. Design Multicentre prospective cohort study over five years. Setting Six university affiliated tertiary care teaching hospitals in Canada. Data collected from November 2000 until November 2005. Participants Neurologically intact adults with a non-traumatic headache peaking within an hour. Main outcome measures Subarachnoid haemorrhage, as defined by any of subarachnoid haemorrhage on computed tomography of the head, xanthochromia in the cerebrospinal fluid, or red blood cells in the final sample of cerebrospinal fluid with positive results on angiography. Physicians completed data collection forms before investigations. Results In the 1999 patients enrolled there were 130 cases of subarachnoid haemorrhage. Mean (range) age was 43.4 (16-93), 1207 (60.4%) were women, and 1546 (78.5%) reported that it was the worst headache of their life. Thirteen of the variables collected on history and three on examination were reliable and associated with subarachnoid haemorrhage. We used recursive partitioning with different combinations of these variables to create three clinical decisions rules. All had 100% (95% confidence interval 97.1% to 100.0%) sensitivity with specificities from 28.4% to 38.8%. Use of any one of these rules would have lowered rates of investigation (computed tomography, lumbar puncture, or both) from the current 82.9% to between 63.7% and 73.5%. Conclusion Clinical characteristics can be predictive for subarachnoid haemorrhage. Practical and sensitive clinical decision rules can be used in patients with a headache peaking within an hour. Further study of these proposed decision rules, including prospective validation, could allow clinicians to be more selective and accurate when investigating patients with headache.

Clinical Decision Rules to Rule Out Subarachnoid Hemorrhage for Acute Headache

IMPORTANCEnThree clinical decision rules were previously derived to identify patients with headache requiring investigations to rule out subarachnoid hemorrhage.nnnOBJECTIVEnTo assess the accuracy, reliability, acceptability, and potential refinement (ie, to improve sensitivity or specificity) of these rules in a new cohort of patients with headache.nnnDESIGN, SETTING, AND PATIENTSnMulticenter cohort study conducted at 10 university-affiliated Canadian tertiary care emergency departments from April 2006 to July 2010. Enrolled patients were 2131 adults with a headache peaking within 1 hour and no neurologic deficits. Physicians completed data forms after assessing eligible patients prior to investigations.nnnMAIN OUTCOMES AND MEASURESnSubarachnoid hemorrhage, defined as (1) subarachnoid blood on computed tomography scan; (2) xanthochromia in cerebrospinal fluid; or (3) red blood cells in the final tube of cerebrospinal fluid, with positive angiography findings.nnnRESULTSnOf the 2131 enrolled patients, 132 (6.2%) had subarachnoid hemorrhage. The decision rule including any of age 40 years or older, neck pain or stiffness, witnessed loss of consciousness, or onset during exertion had 98.5% (95% CI, 94.6%-99.6%) sensitivity and 27.5% (95% CI, 25.6%-29.5%) specificity for subarachnoid hemorrhage. Adding thunderclap headache (ie, instantly peaking pain) and limited neck flexion on examination resulted in the Ottawa SAH Rule, with 100% (95% CI, 97.2%-100.0%) sensitivity and 15.3% (95% CI, 13.8%-16.9%) specificity.nnnCONCLUSIONS AND RELEVANCEnAmong patients presenting to the emergency department with acute nontraumatic headache that reached maximal intensity within 1 hour and who had normal neurologic examination findings, the Ottawa SAH Rule was highly sensitive for identifying subarachnoid hemorrhage. These findings apply only to patients with these specific clinical characteristics and require additional evaluation in implementation studies before the rule is applied in routine clinical care.

Determination of the clinical importance of study results

Formal statistical methods for analyzing clinical trial data are widely accepted by the medical community. Unfortunately, the interpretation and reporting of trial results from the perspective of clinical importance has not received similar emphasis. This imbalance promotes the historical tendency to consider clinical trial results that are statistically significant as also clinically important, and conversely, those with statistically insignificant results as being clinically unimportant. In this paper, we review the present state of knowledge in the determination of the clinical importance of study results. This work also provides a simple, systematic method for determining the clinical importance of study results. It uses the relationship between the point estimate of the treatment effect (with its associated confidence interval) and the estimate of the smallest treatment effect that would lead to a change in a patient’s management. The possible benefits of this approach include enabling clinicians to more easily interpret the results of clinical trials from a clinical perspective, and promoting a more rational approach to the design of prospective clinical trials.

Ottawa Panel Evidence-Based Clinical Practice Guidelines for Strengthening Exercises in the Management of Fibromyalgia: Part 2

Background and Purpose: The objective of this study was to create guidelines for the use of strengthening exercises in the management of adult patients (>18 years of age) with fibromyalgia (FM), as defined by the 1990 American College of Rheumatology criteria. Methods: Following Cochrane Collaboration methods, the Ottawa Methods Group found and synthesized evidence from comparative controlled trials and formed the Ottawa Panel, with nominated experts from key stakeholder organizations. The Ottawa Panel then developed criteria for grading the recommendations based on experimental design (I for randomized controlled trials, II for nonrandomized studies) and strength of evidence (A, B, C+, C, D+, D, or D−). From the rigorous literature search, 5 randomized controlled trials were selected. Statistical analysis was based on Cochrane Collaboration methods. Continuous data were calculated with weighted mean differences between the intervention and control groups, and dichotomous data were analyzed with relative risks. Clinical improvement was calculated using absolute benefit and relative difference in change from baseline. Clinical significance was attained when an improvement of 15% relative to a control was found. Results: There were 5 positive recommendations: 2 grade A and 3 grade C+. All 5 were of clinical benefit. Discussion and Conclusion: The Ottawa Panel recommends strengthening exercises for the management of fibromyalgia as a result of the emerging evidence (grades A, B, and C+, although most trials were rated low quality) shown in the literature.