Emergency Medical Services Compliance With Prehospital Stroke Quality Metrics Is Associated With Faster Stroke Evaluation and Treatment.

BACKGROUND: Emergency medical services (EMS) is an important link in the stroke chain of recovery. Various prehospital quality metrics have been proposed for prehospital stroke care, but their individual impact is uncertain. We sought to measure associations between EMS quality metrics and downstream stroke care. METHODS: This is a retrospective analysis of a cohort of EMS-transported stroke patients assembled through a linkage between Michigan's EMS and stroke registries. We used multivariable regression to quantify the independent associations between EMS quality metric compliance (dispatch within 90 seconds of 911 call, prehospital stroke screen documentation [Prehospital stroke scale], glucose check, last known well time, maintenance of scene times ≤15 minutes, hospital prenotification, and intravenous line placement) and shorter door-to-CT times (door-to-CT ≤25), accounting for EMS recognition, age, sex, race, stroke subtype, severity, and duration of symptoms. We then developed a simple EMS quality score based on metrics associated with early CT and examined its associations with hospital stroke evaluation times, treatment, and patient outcomes. RESULTS: Five thousand seven hundred seven EMS-transported stroke cases were linked to prehospital records from January 2018 through June 2019. In multivariable analysis, prehospital stroke scale documentation (adjusted odds ratio, 1.4 [1.2-1.6]), glucose check (1.3 [1.1-1.6]), on-scene time ≤15 minutes (1.6 [1.4-1.9]), hospital prenotification ([2.0 [1.4-2.9]), and intravenous line placement (1.8 [1.5-2.1]) were independently associated with a door-to-CT ≤25 minutes. A 5-point quality score (1 point for each element) was therefore developed. In multivariable analysis, a 1-point higher EMS quality score was associated with a shorter time from EMS contact to CT (-9.2 [-10.6 to -7.8] minutes; P<0.001) and thrombolysis (-4.3 [-6.4 to -2.2] minutes; P<0.001), and higher odds of discharge to home (adjusted odds ratio, 1.1 [1.0-1.2]; P=0.002). CONCLUSIONS: Five EMS actions recommended by national guidelines were associated with rapid CT imaging. A simple quality score derived from these measures was also associated with faster stroke evaluation, greater odds of reperfusion treatment, and discharge to home.

Prehospital Stroke Care Part 2: On-Scene Evaluation and Management by Emergency Medical Services Practitioners.

The prehospital phase is a critical component of delivering high-quality acute stroke care. This topical review discusses the current state of prehospital acute stroke screening and transport, as well as new and emerging advances in prehospital diagnosis and treatment of acute stroke. Topics include prehospital stroke screening, stroke severity screening, emerging technologies to aid in the identification and diagnosis of acute stroke in the prehospital setting, prenotification of receiving emergency departments, decision support for destination determination, and the capabilities and opportunities for prehospital stroke treatment in mobile stroke units. Further evidence-based guideline development and implementation of new technologies are critical for ongoing improvements in prehospital stroke care.

Emergency Medical Services Stroke Care Performance Variability in Michigan: Analysis of a Statewide Linked Stroke Registry.

Background Emergency medical services (EMS) compliance with recommended prehospital care for patients with acute stroke is inconsistent; however, sources of variability in compliance are not well understood. The current analysis utilizes a linkage between a statewide stroke registry and EMS information system data to explore patient and EMS agency-level contributions to variability in prehospital care. Methods and Results This is a retrospective analysis of a cohort of confirmed stroke cases transported by EMS to hospitals participating in a statewide stroke registry. Using EMS information system data, the authors quantified EMS compliance with 6 performance measures derived from national guidelines for prehospital stroke care: prehospital stroke scale performance, glucose check, stroke recognition, on-scene time ≤15 minutes, time last known well documentation, and hospital prenotification. Multilevel multivariable logistic regression analysis was then used to examine associations between patient-level demographic and clinical characteristics and EMS compliance while accounting for and quantifying the variation attributable to agency of transport and recipient hospital. Over an 18-month period, EMS and stroke registry records were linked for 5707 EMS-transported stroke cases. Compliance ranged from 24% of cases for last known well documentation to 82% for documentation of a glucose check. The other measures were documented in approximately half of cases. Older age, higher National Institutes of Health Stroke Scale, and earlier presentation were associated with more compliant prehospital care. EMS agencies accounted for more than half of the variation in EMS prehospital stroke scale documentation and last known well documentation and 27% of variation in glucose check but <10% of stroke recognition and prenotification variability. Conclusions EMS stroke care remains highly variable across different performance measures and EMS agencies. EMS agency and electronic medical record type are important sources of variability in compliance with key prehospital performance metrics for stroke.

Early Termination of Acute Stroke Randomized Controlled Trials Published Between 2013 and 2020: A Systematic Review.

BACKGROUND: Termination of a clinical trial before the maximum planned sample size is accrued can occur for multiple valid reasons but has implications for the interpretation of results. We undertook a systematic review of contemporary acute stroke trials to document the prevalence of and reasons for early termination. METHODS: We searched MEDLINE for randomized controlled trials of acute stroke therapies published between 2013 and 2020 in 9 major clinical journals. Manuscripts describing the primary results of phase 2 and phase 3 trials of acute stroke care were included. Data on study characteristics and adherence to CONSORT reporting guidelines were abstracted and summarized using descriptive statistics. Where feasible, we compared treatment effect sizes between trials terminated early and those not terminated early. RESULTS: Of 96 randomized controlled trials, 39 (41%) were terminated early, 84 (88%) had a data and safety monitoring board, and 57 (59%) reported a prespecified statistical stopping rule. Among the 39 trials terminated early, 10 were discontinued for benefit, 10 due to logistical issues, 8 for futility, 6 because of newly available evidence, 1 for harm, and 4 for other or a combination of reasons. The median percentage of the maximum planned sample size accrued among trials terminated early was 63% (range, 8%-89%). Only 55% of trials (53 of 96) reported whether interim efficacy analyses were conducted, as recommended by the CONSORT guidelines. When 10 endovascular therapy trials were compared according to early termination status, the effect sizes of trials terminated early for benefit were only modestly larger than those not terminated early. CONCLUSIONS: The high prevalence of early termination in combination with the wide variety of reasons underscores the necessity of meticulous trial planning and adherence to methodological and reporting guidelines for early termination. Registration: URL: https://www.crd.york.ac.uk/prospero/; Unique identifier: CRD42019128727.

Accuracy and Implications of Hemorrhagic Stroke Recognition by Emergency Medical Services.

Background Hemorrhagic stroke is a medical emergency that requires rapid identification and treatment. Despite playing a critical role in the emergency response to hemorrhagic stroke patients, a minimal amount is known about the quality of emergency medical services (EMS) care for this condition. The objectives of this study were to quantify EMS hemorrhagic stroke recognition, identify predictors of accurate EMS recognition, and examine associations between EMS recognition, quality of prehospital care, and patient outcomes. Methods: Consecutive EMS-transported hemorrhagic strokes were identified from medical records at 4 primary stroke centers. Data regarding prehospital care were abstracted from EMS records and linked to in-hospital data. Clinical predictors of accurate EMS recognition were examined using logistic regression. EMS performance measure compliance and hospital outcomes were also compared among EMS recognized and unrecognized hemorrhagic strokes. Results: Over 24 months, EMS-transported 188 hemorrhagic stroke patients; 108 (57.4%) were recognized by EMS. Recognized cases had higher rates of stroke scale documentation (84.3% vs. 20.0%, p < 0.001); multivariable logistic regression confirmed a strong independent relationship between stroke scale documentation and recognition (adjusted OR 15.1 [5.6 to 40.7]). Recognized cases also had shorter on-scene times (15.5 vs. 21 min, p < 0.001) and door-to-computed tomography (DTCT) acquisition times (20 vs. 47 min, p < 0.001). Conclusions: Among EMS-transported hemorrhagic stroke cases, stroke screen documentation was strongly associated with EMS stroke recognition, which was in turn associated with higher quality of EMS care and faster computed tomography (CT) scans upon emergency department arrival.

A Comparison of Probabilistic and Deterministic Match Strategies for Linking Prehospital and in-Hospital Stroke Registry Data.

BACKGROUND: Understanding and improving EMS stroke care requires linking data from both the prehospital and hospital settings. In the US, such data is collected in separate de-identified registries that cannot be directly linked due to lack of a common, unique patient identifier. In the absence of unique patient identifiers two common approaches to linking databases are deterministic matching, which uses combinations of non-unique matching variables to define matches, and probabilistic matching, which generates estimates of match probability based on the degree of similarity between records. This analysis seeks to compare these two approaches for matching EMS and stroke registry data. METHODS: Stroke cases transported by EMS to Michigan hospitals participating in the Michigan Coverdell Acute Stroke Registry were linked to records from Michigan's EMS Information System (MI-EMSIS) between January 2018 and June 2019. Destination hospital, date-of-service, patient age, date-of-birth, and sex were used to perform deterministic and probabilistic linkages. Match rates and representativeness of the matched samples were compared between the two matching strategies. Multivariable logistic regression was used to identify characteristics associated with successful matching. RESULTS: During the 18-month study period there were 8,828 EMS transported confirmed stroke cases in the registry and 620,907 EMS transports to 38 Coverdell registry-participating hospitals. The probabilistic match linked 5985 (67.7%) strokes to EMS records; the deterministic match linked 4012 (45.5%). Within each strategy the characteristics of matched and unmatched cases were similar, with the exception that deterministically matched cases were less likely to be older than 89 (adjusted odds ratio [aOR]=0.3), white (aOR=0.8), and more likely to have subarachnoid hemorrhage (aOR=1.4) than unmatched cases. CONCLUSION: Probabilistic matching resulted in higher match rates and a more representative sample of EMS transported strokes, suggesting it may be superior in assessing EMS stroke care compared to a deterministic approach.

Emergency medical systems education may improve knowledge of pre-hospital stroke triage protocols.

BACKGROUND: Following the results of randomized clinical trials supporting the use of mechanical thrombectomy (MT) with tissue plasminogen activator for emergent large vessel occlusion (ELVO), our state Stroke Task Force convened to: update legislation to recognize differences between Primary Stroke Centers (PSCs) and Comprehensive Stroke Centers (CSCs); and update Emergency Medical Services (EMS) protocols to triage direct transport of suspected ELVO patients to CSCs. PURPOSE: We developed a single-session training curriculum for EMS personnel focused on the Los Angeles Motor Scale (LAMS) score, its use to correctly triage patients as CSC-appropriate in the field, and our state-wide EMS stroke protocol. We assessed the effect of our training on EMS knowledge. METHODS: We assembled a focus group to develop a training curriculum and assessment questions that would mimic real-life conditions under which EMS personnel operate. Ten questions were formulated to assess content knowledge before and after training, and scores were compared using generalized mixed models. RESULTS: Training was provided for 179 EMS providers throughout the state.Average pre-test score was 52.4% (95% CI 49% to 56%). Average post-test score was 85.6% (83%-88%, P<0.0001). Each of the 10 questions was individually assessed and all showed significant gains in EMS knowledge after training (P<0.0001). CONCLUSIONS: A brief educational intervention results in substantial improvements in EMS knowledge of prehospital stroke severity scales and severity-based field triage protocols. Further study is needed to establish whether these gains in knowledge result in improved real-world performance.

The Yield of Multimodal Computed Tomography among Emergency Department Patients with Suspected Large Vessel Occlusion Stroke.

OBJECTIVES: Endovascular therapy (EVT) improves outcomes for appropriately selected acute ischemic stroke patients. Guidelines suggest rapid acquisition of noninvasive vascular imaging to screen suspected ischemic stroke patients for large vessel occlusion (LVO) and candidacy for EVT. We sought to quantify the yield of an LVO stroke screening process in an undifferentiated emergency department (ED) suspected stroke population as well as identify predictors of successful EVT. METHODS: We identified a cohort of consecutive ED patients who received CT angiography and brain perfusion (CTA/P) imaging to determine candidacy for EVT during 2016. In keeping with the guidelines at that time, hospital protocol directed physicians to obtain CTA/P studies if time from the onset of symptoms was less than or equal to 6 hours, and the National Institute of Health Stroke Scale (NIHSS) more than or equal to 6 or if recommended by the consulting stroke neurologist. Final discharge diagnoses, EVT attempts, and successful reperfusion (TICI 2b or better) were recorded. Yield of CTA/P was compared among patients based on NIHSS and duration of symptoms. RESULTS: Over a 12-month period, 406 suspected stroke patients were screened with CTA/P; 273 (67%) received a final diagnosis of ischemic stroke. Among cases screened, 53 (13%) underwent attempted EVT; 35 (9%) achieved successful reperfusion. Only 1 of 113 (1%) patients with an NIHSS less than 6 was successfully treated with EVT compared to 34 of 285 (12%) with higher NIHSS (p = 0.001). The probability of successful EVT declined with increasing symptom duration (p = 0.009 for trend). In multivariable analysis, NIHSS more than or equal to 6 was associated with successful EVT (odds ratio [OR] 4.0 [1.6 to 9.9]) but presentation within 6 hours of onset was not (OR 2.3 [0.8 to 6.7]). CONCLUSIONS: EVT candidates were common among suspected stroke patients screened with CTA/P in the ED, however, patients with NIHSS less than 6 rarely received successful EVT.

Educating Paramedics on the Finger-to-Nose Test Improves Recognition of Posterior Stroke.

Background and Purpose- Emergency medical services (EMS) stroke recognition facilitates rapid care, however, prehospital stroke screening tools rely on signs that are often absent in posterior circulation strokes. We hypothesized that addition of the finger-to-nose (FTN) test to the Cincinnati Prehospital Stroke Scale would improve EMS posterior stroke recognition. Methods- In this controlled before and after study of consecutive EMS transported posterior ischemic strokes, paramedics in a single EMS agency received in-person training in the use of the FTN test. Paramedics at 2 other local EMS agencies served as controls. We compared the change in posterior stroke recognition, door-to-CT times, and alteplase delivery between the FTN (intervention) and control agencies. Results- Over 21 months, 51 posterior circulation strokes were transported by the FTN agency and 88 in the control agencies. Following training, posterior stroke recognition improved from 46% to 74% (P=0.039) in the FTN agency, whereas there was no change in the control agencies (32% before versus 39% after, P=0.467). Mean door-to-CT time in the FTN agency also improved following training (62-41 minutes, P=0.037) but not in the control agencies (58-61 minutes, P=0.771). There was no difference in alteplase delivery. Conclusions- Paramedics trained in the FTN test were more likely to identify posterior stroke. If future studies confirm these findings, such training may expedite the care of posterior stroke patients transported by EMS.

Brief Educational Intervention Improves Emergency Medical Services Stroke Recognition.

Background and Purpose- Recognition of stroke symptoms and hospital prenotification by emergency medical services (EMS) facilitate rapid stroke treatment; however, one-third of patients with stroke are unrecognized by EMS. To promote stroke recognition and quality measure compliant prehospital stroke care, we deployed a 30-minute online EMS educational module coupled with a performance feedback system in a single Michigan county. Methods- During a 24-month study period, a registry of consecutive EMS-transported suspected or unrecognized stroke cases was utilized to perform an interrupted time series analysis of the impact of the EMS education and feedback intervention. For each agency, we compared EMS stroke recognition and quality measure compliance rates, as well as emergency department performance and hospital outcomes during 12 preintervention months with performance in the remaining study months. Results- A total of 1805 EMS-transported cases met inclusion criteria; 1235 (68.4%) of these had ischemic or hemorrhagic strokes or transient ischemic attacks. There were no trends toward improvement in any outcome before the intervention. After the intervention, the EMS stroke recognition rate increased from 63.8% to 69.5% ( P=0.037). Prenotification increased from 60.9% to 77.3% ( P<0.001). Among patients with ischemic stroke/transient ischemic attack, there was a trend toward higher rates of tPA (tissue-type plasminogen activator) delivery (13.9%-17.7%; P=0.096) and a significant increase in tPA delivery within 45 minutes (5.7%-8.9%; P=0.042) after intervention. However, improvements in EMS recognition were limited to the first 3 months following intervention. Conclusions- A brief educational intervention was associated with improved EMS stroke recognition, hospital prenotification, and faster tPA delivery. Gains were primarily observed immediately following education and were not sustained through provision of performance feedback to paramedics.

Emergency Dispatcher Stroke Recognition: Associations with Downstream Care.

OBJECTIVE: As the first point of contact for patients activating emergency medical services (EMS), emergency dispatchers have the earliest opportunity to recognize stroke. We sought to quantify dispatcher stroke recognition and its relationships with EMS stroke recognition and response speed. METHODS: We assembled a cohort of consecutive EMS-transported patients with a dispatcher suspected stroke or a hospital discharge diagnosis of stroke or transient ischemic attack (TIA). Dispatcher sensitivity and positive predictive value (PPV) for stroke recognition were calculated. Multivariable logistic regression analysis was used to determine predictors of dispatcher recognition and relationships between dispatcher recognition and downstream care. RESULTS: During a 12-month period, 601 patients met inclusion criteria. Dispatchers suspected stroke in 229/324 (sensitivity = 70.7% [65.5 to 75.4%]) confirmed stroke/TIA cases and correctly assigned a suspected stroke label in 229/506 cases (PPV = 45.3% [41.0 to 49.6%]). Dispatchers had higher odds of recognizing ischemic strokes (aOR 3.4 [1.4 to 8.5]) and lower odds of recognizing patients with visual deficits (aOR = 0.4 [0.2 to 0.9]) or vomiting (aOR = 0.3 [0.1 to 0.9]). Dispatcher suspected stroke cases received more on-scene stroke screens (79.0% vs. 54.7%, p < 0.0001) and were more often recognized by EMS as strokes (77.7% vs. 57.9%, p = 0.0005). Dispatcher recognition was independently associated with EMS stroke recognition (aOR = 3.8 [1.9 to 7.7]), but not with transportation times, door-to-CT times, or t-PA delivery. CONCLUSIONS: Emergency dispatcher stroke recognition is associated with higher rates of on-scene stroke scale performance and EMS ischemic stroke recognition but not with reduced transport times, door-to-CT times, or t-PA treatment.

Emergency Department Management of Transient Ischemic Attack: A Survey of Emergency Physicians.

BACKGROUND: Patients are at high risk for stroke following a transient ischemic attack (TIA). The ideal setting for evaluating and treating patients with TIA has not been established, resulting in variability in emergency department (ED) TIA management. We conducted a survey to describe ED TIA management and factors that influence disposition determination for TIA patients. METHODS: We administered a mail survey to 480 randomly selected members of the Michigan College of Emergency Physicians. Survey questions addressed current ED TIA management, the acceptability of the ABCD(2) risk-stratification tool, and disposition recommendations for a series of hypothetical TIA patients. RESULTS: A total of 188 (39%) responses were received. Head computed tomography (96.2%) and antiplatelet therapy (88.2%) were the most commonly reported ED interventions. Over 85% of respondents reported admitting most or all TIA patients. The ABCD(2) score had low acceptability among emergency medicine physicians and was rarely incorporated into practice (10.7%). Respondents identified a short-term risk of stroke of less than 2% (95% confidence interval: 1.6-2.4) as an acceptable threshold for discharge; however, most respondents recommended admission even for low-risk TIA patients. Those with access to an outpatient TIA clinic were less likely to admit low-risk TIA patients; those with access to an observation unit were more likely to admit. CONCLUSIONS: In this survey, ED physicians preferred hospital admission for most TIA patients, including those at low risk for stroke. The ABCD(2) risk-stratification tool had low acceptability. Further research is needed to refine risk-stratification tools and define the optimal setting for TIA evaluations.

Clinical predictors of accurate prehospital stroke recognition.

BACKGROUND AND PURPOSE: Prehospital activation of in-hospital stroke response hastens treatment but depends on accurate emergency medical services (EMS) stroke recognition. We sought to measure EMS stroke recognition accuracy and identify clinical factors associated with correct stroke identification. METHODS: Using EMS and hospital records, we assembled a cohort of EMS-transported suspect, confirmed, or missed ischemic stroke or transient ischemic attack cases. The sensitivity and positive predictive value (PPV) for EMS stroke recognition were calculated using the hospital discharge diagnosis as the gold standard. We used multivariable logistic regression analysis to determine the association between Cincinnati Prehospital Stroke Scale use and EMS stroke recognition. RESULTS: During a 12-month period, 441 EMS-transported patients were enrolled; of which, 371 (84.1%) were EMS-suspected strokes and 70 (15.9%) were EMS-missed strokes. Overall, 264 cases (59.9%) were confirmed as either ischemic stroke (n=186) or transient ischemic attack (n=78). The sensitivity of EMS stroke recognition was 73.5% (95% confidence interval, 67.7-78.7), and PPV was 52.3% (95% confidence interval, 47.1-57.5). Sensitivity (84.7% versus 30.9%; P<0.0001) and PPV (56.2% versus 30.4%; P=0.0004) were higher among cases with Cincinnati Prehospital Stroke Scale documentation. In multivariate analysis, Cincinnati Prehospital Stroke Scale documentation was independently associated with EMS sensitivity (odds ratio, 12.0; 95% confidence interval, 5.7-25.5) and PPV (odds ratio, 2.5; 95% confidence interval, 1.3-4.7). CONCLUSIONS: EMS providers recognized 3 quarters of the patients with ischemic stroke and transient ischemic attack; however, half of EMS-suspected strokes were false positives. Documentation of a Cincinnati Prehospital Stroke Scale was associated with higher EMS stroke recognition sensitivity and PPV.

Incorporating diffusion-weighted magnetic resonance imaging into an observation unit transient ischemic attack pathway: a prospective study.

BACKGROUND AND PURPOSE: National guidelines advocate for early, aggressive transient ischemic attack (TIA) evaluations and recommend diffusion-weighted magnetic resonance imaging (MRI) for brain imaging. The purpose of this study is to examine clinician compliance, the yield of MRI, and patient-centered clinical outcomes following implementation of an emergency department observation unit (EDOU) clinical pathway incorporating routine MRI into the acute evaluation of patients with TIA. METHODS: This is a prospective observational study of patients with TIA admitted from the ED. Patients with low-risk TIA were transferred to an EDOU for diagnostic testing including MRI; high-risk patients were directed to hospital admission. Clinical variables, diagnostic tests, and treatment were recorded for all patients. The primary clinical outcome was the rate of stroke or recurrent TIA, determined through telephone follow-up and medical record review at 7 and 30 days. RESULTS: A total of 116 patients with TIA were enrolled. In all, 92 (79.3%) patients were transferred to the EDOU, of whom 69 (59.5%) were discharged without hospitalization. Compliance with the EDOU pathway was 83 (91.2%) of 92. Magnetic resonance imaging demonstrated acute infarct in 16 (15.7%) of 102 patients. Stroke (n = 2) or TIA (n = 3) occurred in 5 patients with TIA (4.3%, 95% confidence interval: 1.6%-10.0%) within 30 days; no strokes occurred after discharge. CONCLUSIONS: Implementation of a TIA clinical pathway incorporating MRI effectively encouraged guideline-compliant diagnostic testing; however, patient-important outcomes appear similar to diagnostic protocols without routine MRI. Further study is needed to assess the benefits and costs associated with routinely incorporating MRI into TIA evaluation.

Does diffusion-weighted imaging predict short-term risk of stroke in emergency department patients with transient ischemic attack?

STUDY OBJECTIVE: The optimal diagnostic evaluation for establishing the risk of stroke among patients presenting to the emergency department (ED) with a transient ischemic attack has not been determined. The objective of this review is to assess the ability of diffusion-weighted magnetic resonance imaging (MRI) to predict the short-term risk of stroke. METHODS: MEDLINE, EMBASE, and the Cochrane Library were queried to identify studies examining the use of diffusion-weighted MRI in patients with classically defined transient ischemic attack. The primary outcome measure was the rate of stroke at 48 hours. Two reviewers determined study eligibility and extracted data. Quality was assessed according to published recommendations for the design and reporting of prognostic studies. RESULTS: One thousand six hundred ninety-six abstracts were identified and 35 articles underwent full-text review. Six cohort studies met the inclusion criteria but were limited by selection bias and differences in duration and completeness of follow-up. Results were not consistent across studies, with 5 reporting higher rates of stroke among diffusion-weighted MRI-positive patients, whereas 1 study reported higher rates in diffusion-weighted MRI-negative patients. Among the 4 studies (N=629 patients) reporting 48-hour outcomes, the risk of stroke ranged from 0% to 2.9% in patients with negative diffusion-weighted MRI findings compared with 0% to 9% among those with positive diffusion-weighted MRI results. CONCLUSION: Studies of variable quality, consistency, and precision suggest that diffusion-weighted MRI may identify patients at sufficiently low risk to warrant ED discharge and close outpatient follow-up.

Evidence-based emergency medicine: clinical synopsis. No clear winner among dressings for partial-thickness burns.

DATA SOURCES: The authors searched the Cochrane Central Register of Controlled Trials (CENTRAL) and the Cochrane Wounds Group Specialized Register (May 29, 2008), MEDLINE (1950 to May 2008), EMBASE (1980 to May 2008), and CINAHL (1982 to May 2008). STUDY SELECTION: The review included randomized controlled trials examining various burn dressings, frequently using silver sulfadiazine as a control. Dressing types included the following: Studies addressing topical skin agents, full-thickness burns, hand burns, and biological skin replacements were excluded. The primary outcomes included time to complete wound healing and change in wound surface area over time. Secondary outcomes included number of dressing changes, pain, patient satisfaction, infection rate, need for surgery, cost, and hospital length of stay. DATA EXTRACTION AND SYNTHESIS: Studies were reviewed by 2 authors independently and data were abstracted using standardized forms. The authors abstracted and pooled data from eligible studies by using appropriate analytical methods according to the Cochrane Handbook, version 5.0.0. Studies were assessed for the adequacy of randomization and allocation concealment, blinding of providers and participants, potential selection bias after allocation, and completeness of follow-up.

Time-efficient laparoscopic skills assessment using an augmented-reality simulator.

BACKGROUND: Computer-based, virtual-reality laparoscopic surgical simulators have several advantages over traditional video trainers. One of these advantages is that performance can be evaluated using unique computer-derived metrics, which can be digitally archived for analysis at a time convenient to instructors. This study sought to determine whether the computer-derived metrics for a unique hybrid simulator correlated with laparoscopic surgical skill. METHODS: For this study, 24 medical students (3rd year), 19 surgical residents (postgraduate years 1-5), and 3 attending surgeons were invited to perform four different tasks three times in a hybrid laparoscopic trainer (ProMIS). Instruction with minimal supervision occurred at a time convenient to each subject. The four tasks in order of complexity were laparoscopic orientation, object positioning, sharp dissection, and intracorporeal knot tying. The metrics automatically recorded were time, path length, and smoothness. The laparoscopic operative experience for each user was quantified using case logs. RESULTS: A statistically significant correlation was observed between experience and performance for all three metrics for tasks 2 to 4 (p < 0.01). Smoothness was the only metric that correlated with the laparoscopic orientation task. Within tasks, time and smoothness correlated much more strongly with experience and to a similar degree. The strongest correlation was observed for the knot-tying task (r(2) = 0.60 for time and 0.59 smoothness). CONCLUSIONS: The computer-derived metrics measured by the hybrid trainer correlate with laparoscopic experience. These metrics are automatically calculated and stored. This may make skills assessment and training a more time-efficient endeavor for instructors and trainees alike. Further study is necessary to determine whether specific metrics are better indicators of actual skill.