Russell D. MacDonald

Paramedic Performance in Calculating Drug Dosages Following Stressful Scenarios in a Human Patient Simulator

Background. Paramedics face many stressors in their work environment. Studies have shown that stress can have a negative effect on the psychological well-being of health professionals. However, there is little published research regarding the effects of stress on the cognitive skills necessary for optimal patient care. Objectives. The primary purpose of this study was to investigate the effects of acute stress on the emotional response andperformance of paramedics. Furthermore, the authors explored whether a paramedics level of training or years of experience would mediate the effects of stress on performance. Methods. Paramedic performances in calculating drug dosages were compared in two stress conditions. In the low-stress condition, 30 paramedics calculated the drug dosages in a quiet classroom free of any stressor. In the high-stress condition, the same paramedics calculated comparable drug dosages immediately after working through a challenging scenario with a human patient simulator. Results. The paramedics obtained lower accuracy scores in the high-stress condition than in the low-stress condition [43% (95% confidence interval [CI]: 36.9–49.2) vs. 58% (95% CI: 48.6–67.1), p < 0.01 based on univariate analysis]. Neither work experience nor level of training predicted the individual differences in the stress-induced performance decrements. Conclusion. These results suggest that the types of stressors encountered in clinical situations can increase medical errors, even in highly experienced individuals. These findings underline the need for more research to determine the mechanisms by which stress influences clinical performance, with the ultimate goal of targeting education or technologic interventions to those tasks, situations, andindividuals most likely to benefit from such interventions.

Outcomes of interfacility critical care adult patient transport: a systematic review

IntroductionWe aimed to determine the adverse events and important prognostic factors associated with interfacility transport of intubated and mechanically ventilated adult patients.MethodsWe performed a systematic review of MEDLINE, CENTRAL, EMBASE, CINAHL, HEALTHSTAR, and Web of Science (from inception until 10 January 2005) for all clinical studies describing the incidence and predictors of adverse events in intubated and mechanically ventilated adult patients undergoing interfacility transport. The bibliographies of selected articles were also examined.ResultsFive studies (245 patients) met the inclusion criteria. All were case-series and two were prospective in design. Due to the paucity of studies and significant heterogeneity in study population, outcome events, and results, we synthesized data in a qualitative manner. Pre-transport severity of illness was reported in only one study. The most common indication for transport was a need for investigations and/or specialist care (three studies, 220 patients). Transport modalities included air (fixed or rotor wing; 66% of patients) and ground (31%) ambulance, and commercial aircraft (3%). Transport teams included a physician in three studies (220 patients). Death during transfer was rare (n = 1). No other adverse events or significant therapeutic interventions during transport were reported. One study reported a 19% (28/145) incidence of respiratory alkalosis on arrival and another study documented a 30% overall intensive care unit mortality, while no adverse events or outcomes were reported after arrival in the three other studies.ConclusionInsufficient data exist to draw firm conclusions regarding the mortality, morbidity, or risk factors associated with the interfacility transport of intubated and mechanically ventilated adult patients. Further study is required to define the risks and benefits of interfacility transfer in this patient population. Such information is important for the planning and allocation of resources related to transporting critically ill adults.

Pre-Hospital Care Management of a Potential Spinal Cord Injured Patient: A Systematic Review of the Literature and Evidence-Based Guidelines

An interdisciplinary expert panel of medical and surgical specialists involved in the management of patients with potential spinal cord injuries (SCI) was assembled. Four key questions were created that were of significant interest. These were: (1) what is the optimal type and duration of pre-hospital spinal immobilization in patients with acute SCI?; (2) during airway manipulation in the pre-hospital setting, what is the ideal method of spinal immobilization?; (3) what is the impact of pre-hospital transport time to definitive care on the outcomes of patients with acute spinal cord injury?; and (4) what is the role of pre-hospital care providers in cervical spine clearance and immobilization? A systematic review utilizing multiple databases was performed to determine the current evidence about the specific questions, and each article was independently reviewed and assessed by two reviewers based on inclusion and exclusion criteria. Guidelines were then created related to the questions by a national Canadian expert panel using the Delphi method for reviewing the evidence-based guidelines about each question. Recommendations about the key questions included: the pre-hospital immobilization of patients using a cervical collar, head immobilization, and a spinal board; utilization of padded boards or inflatable bean bag boards to reduce pressure; transfer of patients off of spine boards as soon as feasible, including transfer of patients off spinal boards while awaiting transfer from one hospital institution to another hospital center for definitive care; inclusion of manual in-line cervical spine traction for airway management in patients requiring intubation in the pre-hospital setting; transport of patients with acute traumatic SCI to the definitive hospital center for care within 24 h of injury; and training of emergency medical personnel in the pre-hospital setting to apply criteria to clear patients of cervical spinal injuries, and immobilize patients suspected of having cervical spinal injury.

Incidence and predictors of critical events during urgent air–medical transport

Background: Little is known about the risks of urgent air–medical transport used in regionalized health care systems. We sought to determine the incidence of intransit critical events and identify factors associated with these events. Methods: We conducted a population-based, retrospective cohort study using clinical and administrative data. We included all adults undergoing urgent air–medical transport in the Canadian province of Ontario between Jan. 1, 2004, and May 31, 2006. The primary outcome was in-transit critical events, which we defined as death, major resuscitative procedure, hemodynamic deterioration, or inadvertent extubation or respiratory arrest. Results: We identified 19 228 patients who underwent air–medical transport during the study period. In-transit critical events were observed in 5.1% of all transports, for a rate of 1 event per 12.6 hours of transit time. Events consisted primarily of new hypotension or airway management procedures. Independent predictors of critical events included female sex (adjusted odds ratio [OR] 1.3, 95% confidence interval [CI] 1.1–1.5), assisted ventilation before transport (adjusted OR 3.0, 95% CI 2.3–3.7), hemodynamic instability before transport (adjusted OR 3.2, 95% CI 2.5–4.1), transport in a fixed-wing aircraft (adjusted OR 1.5, 95% CI 1.2–1.8), increased duration of transport (adjusted OR 1.02 per 10-minute increment, 95% CI 1.01–1.03), on-scene calls (adjusted OR 1.7, 95% CI 1.4–2.1) and type of crew (adjusted OR 0.6 for advanced care paramedics v. critical care paramedics, 95% CI 0.5–0.7). Interpretation: Critical events occurred in about 1 in every 20 air–medical transports and were associated with multiple risk factors at the patient, transport and system levels. These findings have implications for the refinement of training of paramedic transport crews and processes for triage and transport.

Impact of prompt defibrillation on cardiac arrest at a major international airport.

Objective. To describe the impact of a rapidly deployable, automated external defibrillator (AED)-equipped first-responder service at Bostons Logan International Airport on the rate of survival to hospital discharge after cardiac arrest. Methods. A prospective observational outcome study was undertaken for cardiac arrests taking place on the airport grounds from January 1, 1995, to December 31, 1999. Patients were included if they were unresponsive, they had no palpable pulse and no spontaneous respirations, an AED was turned on, and the cardac arrest took place on airport grounds. Airport fire rescue and emergency medical services (EMS) personnel submitted resuscitation records and AED memory modules for each cardiac arrest. Each author independently reviewed all cardiac arrest reports and code summaries to ensure accuracy and data integrity. Relevant dispatch and response times were determined from airport fire rescue and EMS dispatch records. Patient outcome was determined from hospital patient records. Descriptive statistics were calculated. Results. The airport fire rescue crew responded to 53 cardiac arrests. Of those, 38 met inclusion criteria. In 36 of 38 cases (94.7%), the airport fire rescue crew was first to apply the defibrillator, and the first to deliver a shock in 28 of 32 cases (87.5%) where a shock was delivered. The median response time for the airport fire rescue crew was 2 minutes, with a mode of 1 minute. The EMS response times were 5:29 (95% CI 4:37–6:19) for basic life support crews and 8:07 (95% CI 7:17–8:57) for advanced life support crews. All patients who survived to hospital admission (n = 15) and hospital discharge (n = 8) received their first shock by the airport fire rescue crew. Eight patients (21.1%) survived to hospital discharge. In five of the eight survivors to hospital discharge, defibrillation by the airport crew alone achieved a return of spontaneous circulation. Conclusions. A rapidly deployable first-responder service permits early defibrillation minutes before arrival of EMS personnel. This rapid response positively impacts the return of spontaneous circulation and survival to hospital discharge after cardiac arrest.

Impact of prehospital mode of transport after severe injury: a multicenter evaluation from the Resuscitation Outcomes Consortium.

BACKGROUND: There is ongoing controversy about the relative effectiveness of air medical versus ground transportation for severely injured patients. In some systems, air medical crews may provide a higher level of care but may require longer transport times. We sought to evaluate the impact of mode of transport on outcome based on analysis of data from two randomized trials of prehospital hypertonic resuscitation. METHODS: Injured patients were enrolled based on prehospital evidence of hypovolemic shock (systolic blood pressure ⩽70 mm Hg or systolic blood pressure = 71–90 mm Hg with heart rate ≥108 bpm) or severe traumatic brain injury (TBI; Glasgow Coma Scale score ⩽8). Patient demographics, injury severity, and physiology were compared based on mode of transport. Multivariate logistic regression was used to determine the impact of mode of transport on 24-hour and 28-day survival for all patients and 6-month extended Glasgow Outcome Scale for patients with TBI, adjusting for differences in injury severity. RESULTS: Included were 2,049 patients, of which 703 (34%) were transported by air. Patients transported by air were more severely injured (mean Injury Severity Score, 30.3 vs. 22.8; p < 0.001), more likely to be in the TBI cohort (70% vs. 55.4%; p < 0.001), and more likely blunt mechanism (94.0% vs. 78.1%; p < 0.001). Patients transported by air had higher rates of prehospital intubation (81% vs. 36%; p < 0.001), received more intravenous fluids (mean 1.3 L vs. 0.8 L; p < 0.001), and had longer prehospital times (mean 76.1 minutes vs. 43.5 minutes; p < 0.001). Adjusted analysis revealed no significant impact of mode of transport on survival or 6-month neurologic outcome (air transport—28-day survival: odds ratio, 1.11; 95% confidence interval, 0.82–1.51; 6-month extended Glasgow Outcome Scale score ⩽4: odds ratio, 0.94; 95% confidence interval, 0.68–1.31). CONCLUSION: There was no difference in the adjusted clinical outcome according to mode of transport. However, air medical transported more severely injured patients with more advanced life support procedures and longer prehospital time. LEVEL OF EVIDENCE: III.

Pro/con debate: Do the benefits of regionalized critical care delivery outweigh the risks of interfacility patient transport?

You are providing input in planning for critical care services to a large regional health authority. You are considering concentrating some critical care services into high-volume regional centres of excellence, as has been done in other fields of medicine. In your region, this would require several centres with differing levels of expertise that are geographically separated. Given there are inherent risks and time delays associated with interfacility patient transport, you debate whether these potential risks outweigh the benefits of regional centres of excellence.

Increased trauma center volume is associated with improved survival after severe injury: Results of a resuscitation outcomes consortium study

Objective:To investigate the relationship between trauma center volume and outcome. Background:The Resuscitation Outcomes Consortium is a network of 11 centers and 60 hospitals conducting emergency care research. For many procedures, high-volume centers demonstrate superior outcomes versus low-volume centers. This remains controversial for trauma center outcomes. Methods:This study was a secondary analysis of prospectively collected data from the Resuscitation Outcomes Consortium multicenter out-of-hospital Hypertonic Saline Trial in patients with Glasgow Coma Scale score of 8 or less (traumatic brain injury) or systolic blood pressure of 90 or less and pulse of 110 or more (shock). Regression analyses evaluated associations between trauma volume and the following outcomes: 24-hour mortality, 28-day mortality, ventilator-free days, Multiple Organ Dysfunction Scale incidence, worst Multiple Organ Dysfunction Scale score, and poor 6-month Glasgow Outcome Scale—Extended score. Results:A total of 2070 patients were evaluated: 1251 in the traumatic brain injury cohort and 819 in the shock cohort. Overall, 24-hour and 28-day mortality was 16% and 25%, respectively. For every increase of 500 trauma center admissions, there was a 7% decreased odds of 24-hour and 28-day mortality for all patients. As trauma center volume increased, nonorgan dysfunction complications increased, ventilator-free days increased, and worst Multiple Organ Dysfunction Scale score decreased. The associations with higher trauma center volume were similar for the traumatic brain injury cohort, including better neurologic outcomes at 6 months, but not for the shock cohort. Conclusions:Increased trauma center volume was associated with increased survival, more ventilator-free days, and less severe organ failure. Trauma system planning and implementation should avoid unnecessary duplication of services.

Critical Events During Land-Based Interfacility Transport

STUDY OBJECTIVE The risks associated with urgent land-based transport of critically ill patients are not well known and have important implications for patient safety, care delivery, and policy development. We seek to determine the incidence of in-transit critical events and associated patient- and transport-level factors. METHODS We conducted a retrospective cohort study using clinical and administrative data. We included adults undergoing urgent land-based critical care transport by a dedicated transport provider between January 1, 2005, and December 31, 2010. The primary outcome was in-transit critical event, defined by adverse events or resuscitative procedures. RESULTS In-transit critical events were observed in 333 (6.5%) of 5,144 urgent land transports. New hypotension (4.4%) or new vasopressors (1.6%) were the most common critical events, with fewer respiratory events (1.3%). Advanced care paramedics had a higher rate compared with critical care paramedics (odds ratio [OR] 1.6; 95% confidence interval [CI] 1.1 to 2.2), especially for patients with baseline hemodynamic instability. In multivariate analysis, mechanical ventilation (adjusted OR 1.7; 95% CI 1.3 to 2.2), baseline hemodynamic instability (adjusted OR 3.7; 95% CI 2.8 to 4.9), out-of-hospital duration (adjusted OR 3.6; 95% CI 2.9 to 4.5 per log-fold increase in time), and neurologic diagnosis (adjusted OR 0.5; 95% CI 0.3 to 0.7 compared with that of medical patients) were associated with critical events. CONCLUSION Critical events occurred in approximately 1 in 15 transports and were associated with mechanical ventilation, hemodynamic instability, and transport duration, and were less frequent in neurologic patients. The finding that hypotension is common and predicted by pretransport hemodynamic instability has implications for the preparation and management of this patient group.

The Toronto prehospital hypertonic resuscitation—head injury and multiorgan dysfunction trial: Feasibility study of a randomized controlled trial

OBJECTIVE The aim of the study was to evaluate the feasibility of a prehospital trial comparing hypertonic saline and dextran (HSD) with normal saline (NS) in blunt head injury patients. DESIGN The study used a double blind randomized trial. SETTING The study was conducted in air and land emergency medical services and 2 trauma centers serving a population of 4 million people. PATIENTS The study population consisted of head injured, blunt trauma adult patients with a Glasgow Coma Scale of lower than 9. INTERVENTIONS We used 250 mL of HSD vs NS given within 4 hours of the accident. MEASUREMENTS The specific objectives were to assess protocol-related logistical issues, randomization, HSD safety, and follow up rates and to obtain survival and neurocognitive end point estimates. MAIN RESULTS Of 132 eligible patients, 113 were randomized. Nineteen eligible patients were missed because of lack of time (9 [22%]), paramedic discretion (3 [7%]), the paramedic forgot (6 [15%]), and the paramedic refused (1 [2%]). Randomization compliance was 96% (109/113). Four randomized cases met exclusion criteria: penetrating trauma (1), cardiac arrest (2), and fall from standing (1). Three randomized patients were excluded from the final analysis: 2 patients received less than 50 mL of study solution due to an interstitial intravenous line and 1 lost randomization identification. Fifty patients (47%) were randomized to HSD and 56 (53%) to NS. Mean injury severity score was 32.7 for HSD and 32.6 for NS. There was no difference in length of stay, Sequential Organ Failure Assessment maximum, Multiple Organ Dysfunction Score maximum, delta Multiple Organ Dysfunction Score, or Apache scores. Initial head scans scored 3 or higher by Marshall classification for 12 HSD and 11 NS patients. Zero adverse events occurred, and follow-up for the primary outcome was 100%. Alive at 30 days for HSD and NS, respectively, was 70% (35/50) and 75% (42/56) and at discharge was 68% (34/50) and 73% (41/56). Only 49.3% (37/77) of surviving patients consented to follow-up at 4 months and 89% (33/37) completed the assessment. Disability rating scale (median, interquartile range) was 3 (0, 6) for HSD and was 0 (0, 6) for NS. Glasgow Outcome Scale Evaluation was higher than 4 for HSD (12/12 [100%]) and NS (15/21 [72%]). Functional Independence Measure (mean, SD) was 62 (37) for HSD and 80 (32) for NS. CONCLUSIONS It is feasible to conduct a prehospital randomized controlled trial with HSD for treatment of blunt trauma patients with head injuries; however, consent for neurofunctional outcomes in this cohort is problematic and threatens the feasibility of definitive trials using these potentially meaningful end points.