Air Quality Monitoring During High-Level Biocontainment Ground Transport: Observations From Two Operational Exercises.

OBJECTIVE: Stretcher transport isolators provide mobile, high-level biocontainment outside the hospital for patients with highly infectious diseases, such as Ebola virus disease. Air quality within this confined space may pose human health risks. METHODS: Ambient air temperature, relative humidity, and CO2 concentration were monitored within an isolator during 2 operational exercises with healthy volunteers, including a ground transport exercise of approximately 257 miles. In addition, failure of the blower unit providing ambient air to the isolator was simulated. A simple compartmental model was developed to predict CO2 and H2O concentrations within the isolator. RESULTS: In both exercises, CO2 and H2O concentrations were elevated inside the isolator, reaching steady-state values of 4434 ± 1013 ppm CO2 and 22 ± 2 mbar H2O in the first exercise and 3038 ± 269 ppm CO2 and 20 ± 1 mbar H2O in the second exercise. When blower failure was simulated, CO2 concentration exceeded 10 000 ppm within 8 minutes. A simple compartmental model predicted CO2 and H2O concentrations by accounting for human emissions and blower air exchange. CONCLUSIONS: Attention to air quality within stretcher transport isolators (including adequate ventilation to prevent accumulation of CO2 and other bioeffluents) is needed to optimize patient safety.

Double Sequential Defibrillation for Refractory Ventricular Fibrillation: A Case Report.

A 40-year-old male struck his chest against a pole during a basketball game and had sudden out-of-hospital cardiac arrest. After bystander cardiopulmonary resuscitation, fire and emergency medical services personnel provided six defibrillation attempts prior to emergency department arrival. A 7th attempt in the emergency department using a different vector was unsuccessful. On the 8th attempt, using a second defibrillator with defibrillator pads placed adjacent to the primary set of defibrillator pads, two shocks were administered in near simultaneous fashion. The double sequential defibrillation was successful and the patient had return of spontaneous circulation at the next pulse check. He recovered in the intensive care unit, was discharged home 1 month later, and continues to follow up in clinic over 1 year later with a Cerebral Performance Category score of 1 (short-term memory deficits).

Accuracy of emergency medical services-reported last known normal times in patients suspected with acute stroke.

BACKGROUND AND PURPOSE: The last known normal (LKN) time is a critical determinant of IV tissue-type plasminogen activator (IV tPA) eligibility; however, the accuracy of emergency medical services (EMS)-reported LKN times is unknown. We determined the congruence between neurologist-determined and EMS-reported LKN times and identified predictors of incongruent LKN times. METHODS: We prospectively collected EMS-reported LKN times for patients brought into the emergency department with suspected acute stroke and calculated the absolute difference between the neurologist-determined and EMS-reported LKN times (|ΔLKN|). We determined the rate of inappropriate IV tPA use if EMS-reported times had been used in place of neurologist-determined times. Univariate and multivariable linear regression assessed for any predictors of prolonged |ΔLKN|. RESULTS: Of 251 patients, mean and median |ΔLKN| were 28 and 0 minutes, respectively. |ΔLKN| was <15 minutes in 91% of the entire cohort and <15 minutes in 80% of patients with a diagnosis of stroke (n=86). Of patients who received IV tPA, none would have been incorrectly excluded from IV tPA if the EMS LKN time had been used. Conversely, of patients who did not receive IV tPA, 6% would have been incorrectly included for IV tPA consideration had the EMS time been used. In patients with wake-up stroke symptoms, EMS underestimated LKN times: mean neurologist LKN time-EMS LKN time=208 minutes. The presence of wake-up stroke symptoms (P<0.0001) and older age (P=0.019) were independent predictors of prolonged |ΔLKN|. CONCLUSIONS: EMS-reported LKN times were largely congruent with neurologist-determined times. Focused EMS training regarding wake-up stroke symptoms may further improve accuracy.

Principles governing heart failure therapy re-examined relative to standard evidence-based medicine-driven guidelines.

Although all aspects of clinical work nowadays are modified by the pervading influence of evidence-based medicine (EBM) and multiplicative guidelines, not many clinicians realize that the underlying premise of EBM-driven guidelines is a particular strain of consequentialist ideology. Subservience to this ideology has transformed modern medical practice, but there is a real risk of distorting good medical practice, of belittling clinical judgement, of disempowering clinicians, and subjecting patients to skewed medical reality and treatment options. With so many heart failure (HF) guidelines issued by various august bodies, it is therefore timely to reappraise principles governing modern HF therapy with a fresh examination of the hierarchy of medical imperatives, the role of alternatives to consequentialism including deontological principles in HF therapy. In addition, other ideology worth re-examining, aside from EBM, are the principle of appropriate definition of HF underlying therapeutic goals and the principle of prioritizing objectives of HF therapy. Even within standard EBM, there are many questions to reconsider: about what types of evidence are admissible, different interpretations of available evidence, emphasizing patient-centered outcome measures instead of randomized controlled trials quantifiable therapeutic outcomes, how to prescribe drugs for prognostic versus symptomatic benefits, and how to deliver HF therapy based on pathophysiological features through mechanistic considerations and not just confined to randomized controlled trials or meta-analytical statistical imperatives. Through re-examination of these fundamental principles of HF therapy, it is hoped that clinicians will be empowered to manage HF patients more holistically and better deliver HF therapies in the best interest of each individual patient.

Evolution of the literature identifying physicians' roles in leadership, clinical development, and practice of the subspecialty of emergency medical services.

PURPOSE: The 2007 Institute of Medicine report entitled Emergency Medical Services at the Crossroads identified a need for the establishment of physician subspecialty certification in emergency medical services (EMS). The purpose of this study was to identify and explore the evolution of publications that define the role of the physician in EMS systems in the United States. METHODS: Three comprehensive searches were undertaken to identify articles that define the physician's role in the leadership, clinical development, and practice of EMS. Independent reviewers then evaluated these articles to further determine whether the articles identified the physician's role in EMS. Then, identified articles were classified by the type of publication in order to evaluate the transition from a non-peer reviewed to peer-reviewed literature base and an analysis was performed on the differences in the growth between these two groups. In addition, for the peer-reviewed articles, an analysis was performed to identify the proportion of articles that were quantitative versus qualitative in nature. RESULTS: The comprehensive review identified 1,504 articles. Ninety articles were excluded due to lack of relevance to the US. The remaining 1,414 articles were reviewed, and 194 papers that address the physician's role within EMS systems were identified; 72 additional articles were identified by hand search of references for a total of 266 articles. The percentage of peer-reviewed articles has increased steadily over the past three decades. In addition, the percentage of quantitative articles increased from the first decade to the second and third decades. CONCLUSIONS: This comprehensive review demonstrates that over the past 30 years an evidence base addressing the role of the physician in EMS has developed. This evidence base has steadily evolved to include a greater proportion of peer-reviewed, quantitative literature.

So many definitions of heart failure: are they all universally valid? A critical appraisal.

Defining heart failure (HF) is a matter of finding the most appropriate words to formulate the definiens for HF that will be universally applicable in all specific circumstances pertaining to the nature of HF. Currently available definitions of HF contain ambiguities and notable deficiencies such that non-heart failure medical conditions can become mislabelled as heart failure. Principles of how best to formulate definitions have been employed to provide a guide on how to appraise published definitions of HF. A fundamental requirement of a good definition is that it should be universal, and by this criterion, we need to question the validity of a conventional dogma that a collection of clinical diagnostic features are equivalent to HF definitions. A long-standing deficiency in HF definitions is the inability to take into account the quantifiable extent of functional impairment of the heart. Other traditional misconceptions surrounding HF definitions have also been addressed. In line with Derek Gibson's proposal, we have rephrased William Harvey's description of the cardiac role in maintaining the circulation in terms of Newtonian physics and of the Law of Conservation of Energy to reach a more universal and less ambiguous definition of HF, with the objective of advancing the science of HF and the treatment of this distressing condition.

Resident-based acute stroke protocol is expeditious and safe.

BACKGROUND AND PURPOSE: The decision to administer tPA to acute stroke patients is frequently made by stroke attendings or fellows, but placing residents in this position may make tPA delivery more efficient. METHODS: Beginning in 2004, we instituted a resident-based acute stroke protocol placing neurology residents in decision-making roles. Time-intervals, symptomatic hemorrhage rate, and discharge locations were prospectively collected and compared between two epochs, before and after 2004. RESULTS: 59 acute ischemic stroke patients were treated with tPA before protocol initiation (1998 to 2002), while 113 patients were treated after protocol initiation (2004 to 2007). The average door-to-needle and onset-to-needle times were significantly shorter after initiation of the resident-based protocol (81 versus 60 minutes [P<0.001] and 138 versus 126 minutes [P<0.05]), respectively. Symptomatic hemorrhage rate (5.1% versus 3.5%) and favorable discharge location (68% versus 76%) did not differ between the two time periods. CONCLUSIONS: A resident-driven tPA protocol, with formal training and quality control, is safe and efficient.