Defibrillator Design and Usability May Be Impeding Timely Defibrillation.

BACKGROUND: Timely defibrillation is the only rhythm-specific therapy proven to increase survival to hospital discharge following cardiac arrest secondary to ventricular tachyarrhythmia. Delayed defibrillation occurs in more than 30% of this population. A study was conducted to test the hypothesis that unintuitive defibrillator design and lack of usability are barriers to timely defibrillation, as measured by time to defibrillation and the proportion of defibrillations delivered within 2 minutes. METHODS: A mixed-methods (qualitative and quantitative) prospective usability study was performed to evaluate the use of a defibrillator in a simulated hospital environment. Participants were asked to perform two simulated tasks typical of in-hospital cardiac arrest care: defibrillation and synchronized cardioversion. RESULTS: The average time to defibrillation was 4 minutes 21 seconds. Only 9.1% of participants (2/22) performed a defibrillation within 2 minutes. Participants had difficulty with several aspects of defibrillator use, including attaching the hands-free defibrillator electrode pads and selecting an appropriate display. Participants rated defibrillator design 4.2 ± 1.8 (mean, standard deviation) on a perceived usability scale (1 = "poorly designed"; 9 = "perfectly designed"). CONCLUSION: Most participants were unable to perform a simulated defibrillation within 2 minutes. This delay in defibrillation was likely at least partially the result of poor defibrillator design and lack of usability. Expert observation and participant feedback were largely congruent in terms of which aspects of defibrillator design do not suit the end user. Modification of future defibrillator design, along with improved education and training, may result in more timely defibrillation.

Incidence and trends of central line associated pneumothorax using radiograph report text search versus administrative database codes.

BACKGROUND: Central line associated pneumothorax (CLAP) could be a good quality of care indicator because they are objectively measured, clearly undesirable and possibly avoidable. We measured the incidence and trends of CLAP using radiograph report text search with manual review and compared them with measures using routinely collected health administrative data. METHODS: For each hospitalisation to a tertiary care teaching hospital between 2002 and 2015, we searched all chest radiography reports for a central line with a sensitive computer algorithm. Screen positive reports were manually reviewed to confirm central lines. The index and subsequent chest radiography reports were screened for pneumothorax followed by manual confirmation. Diagnostic and procedural codes were used to identify CLAP in administrative data. RESULTS: In 685 044 hospitalisations, 10 819 underwent central line insertion (1.6%) with CLAP occurring 181 times (1.7%). CLAP risk did not change over time. Codes for CLAP were inaccurate (sensitivity 13.8%, positive predictive value 6.6%). However, overall code-based CLAP risk (1.8%) was almost identical to actual values possibly because patient strata with inflated CLAP risk were balanced by more common strata having underestimated CLAP risk. Code-based methods inflated central line incidence 2.2 times and erroneously concluded that CLAP risk decreased significantly over time. CONCLUSIONS: Using valid methods, CLAP incidence was similar to those in the literature but has not changed over time. Although administrative database codes for CLAP were very inaccurate, they generated CLAP risks very similar to actual values because of offsetting errors. In contrast to those from radiograph report text search with manual review, CLAP trends decreased significantly using administrative data. Hospital CLAP risk should not be measured using administrative data.

Comparing health behaviours of internal medicine residents and medical students: an observational study.

PURPOSE: During residency, many physicians find it difficult to maintain a healthy lifestyle; however, there is little objective data available. In this study, residents' health behaviours and cardiovascular risk status were compared with those of medical students. METHODS: Medical residents (n=55, postgraduate years 1 to 4) were compared with medical students (n=62, years 1-4). The main dependent variable was the average number of steps per day (assessed using a pedometer) at work and leisure over three days, during which subjects were not on call or post-call. In addition, all subjects completed a three day food log. Frequency of vigorous exercise was assessed by a single question. Body mass index (BMI), waist circumference, blood pressure, total and high-density lipoprotein cholesterol, smoking habits and random blood glucose were measured, and Framingham Risk Score coronary artery disease 10 year probabilities (FRS) were calculated. RESULTS: Residents recorded 8344±3520 steps per day while students recorded 10703±3986 (p < 0.002). 35% of residents and 52% of students averaged more than 10,000 steps per day and senior residents took fewer steps than junior residents. Both groups frequently failed to achieve the recommended daily servings of fruits and vegetables; on average, 3.5±2.0 servings for residents and 5.4±2.2 for students (p < 0.0001). BMI and FRS were higher among the residents in comparison with the students. CONCLUSION: Medical residents at our institution appear less active and consume fewer servings of fruits and vegetables than undergraduate medical students. These differences are associated with higher BMI, waist circumference and cardiovascular risk.