Lucas A. Myers

Comparison of prehospital insertion success rates and time to insertion between standard endotracheal intubation and a supraglottic airway

OBJECTIVE To compare paramedic insertion success rates and time to insertion between standard ETI and a supraglottc airway device (King LTS-D™) in patients needing advanced airway management. METHODS Between June 2008 and June 2009, consented paramedics from 4 EMS systems performed ETI or placed a King LTS-D according to a predetermined randomization calendar. Data collection occurred following each placement via telephone. Placement success (ability to ventilate to chest rise, absence of gastric sounds, presence of bilateral lung sounds, and when applicable, quantitative end-tidal CO(2) reading) was compared between treatment groups. Time to ventilation (time from airway device in hand ready to place to time of first successful ventilation) was also compared. RESULTS A total of 213 patients in need of advanced airway management were treated during the study period, with 9 patients excluded from the analysis. The remaining 204 placements by 110 of the 272 consented paramedics were analyzed (median placements per paramedic=1; range=1-7). The overall placement success rate was virtually equal across the two groups (ETI=80.2%, King LTS-D=80.5%; p=0.97). The median time to placement between ETI and the King LTS-D was also not significantly different (ETI=19.5s vs. King LTS-D=20.0s; z=-0.25; p=0.80). CONCLUSION In this study, no differences in placement success rate or time to insertion were detected between the King LTS-D and ETI.

Population-Based Study of Severe Hypoglycemia Requiring Emergency Medical Service Assistance Reveals Unique Findings

Objective: The objective is to report a contemporary population-based estimate of hypoglycemia requiring emergency medical services (EMS), its burden on medical resources, and its associated mortality in patients with or without diabetes mellitus (DM, non-DM), which will enable development of prospective strategies that will capture hypoglycemia promptly and provide an integrated approach for prevention of such episodes. Methods: We retrieved all ambulance calls activated for hypoglycemia in Olmsted County, Minnesota, between January 1, 2003 and December 31, 2009. Results: A total of 1473 calls were made by 914 people (DM 8%, non-DM 16%, unknown DM status 3%). Mean age was 60 ± 16 years with 49% being female. A higher percentage of calls were made by DM patients (87%) with proportionally fewer calls coming from non-DM patients (11%) (chi-square test, p < .001), and the remaining 2% calls by people with unknown DM status. Emergency room transportation and hospitalization were significantly higher in non-DM patients compared to DM patients (p < .001) and type 2 diabetes mellitus compared to type 1 diabetes mellitus (p < .001). Sulphonylureas alone or in combination with insulin varied during the study period (p = .01). The change in incidence of EMS for hypoglycemia was tracked during this period. However, causality has not been established. Death occurred in 240 people, 1.2 (interquartile range 0.2–2.7) years after their first event. After adjusting for age, mortality was higher in non-DM patients compared with DM patients (p < .001) but was not different between the two types of DM. Conclusions: The population burden of EMS requiring hypoglycemia is high in both DM and non-DM patients, and imposes significant burden on medical resources. It is associated with long-term mortality.

Performance of a rectilinear biphasic waveform in defibrillation of presenting and recurrent ventricular fibrillation: A prospective multicenter study

OBJECTIVES We tested the hypothesis that shock success differs with initial and recurrent episodes of ventricular fibrillation (VF). METHODS From September 2008 to March 2010 out-of-hospital cardiac arrest patients with VF as the initial rhythm at 9 study sites were defibrillated by paramedics using a rectilinear biphasic waveform. Shock success was defined as termination of VF within 5s post-shock. We used generalized estimating equation (GEE) analysis to assess the association between shock type (initial versus refibrillation) and shock success. RESULTS Ninety-four patients presented in VF. Mean age was 65.4 years, 78.7% were male, and 80.9% were bystander-witnessed. VF recurred in 75 (79.8%). There were 338 shocks delivered for initial (n = 90) or recurrent (n = 248) VF available for analysis. Initial shocks terminated VF in 79/90 (87.8%) and subsequent shocks in 209/248 (84.3%). GEE odds ratio (OR) for shock type was 1.37 (95% CI 0.68-2.74). After adjusting for potential confounders, the OR for shock type remained insignificant (1.33, 95% CI 0.60-2.53). We observed no significant difference in ROSC (54.7% versus 52.6%, absolute difference 2.1%, p = 0.87) or neurologically intact survival to hospital discharge (21.9% versus 33.3%, absolute difference 11.4%, p = 0.31) between those with and without VF recurrence. CONCLUSIONS Presenting VF was terminated with one shock in 87.8% of cases. We observed no significant difference in the frequency of shock success between initial versus recurrent VF. VF recurred in the majority of patients and did not adversely affect shock success, ROSC, or survival.

Prehospital peripheral intravenous vascular access success rates in children.

Abstract Objective. Achieving successful peripheral intravenous (PIV) vascular access in children can be difficult. In the prehospital setting, opportunities are rare. Obtaining access becomes vital in emergent and life-threating conditions, such as seizures, hypoglycemia, and cardiac arrest. This study examines prehospital pediatric PIV attempts, success rates, and the impact of patient age. Methods. This was a retrospective chart review of patients aged 18 years or younger receiving prehospital PIV attempts from January 1, 2003, through May 31, 2011. Included cases were identified by querying electronic patient care reports for PIV attempts within the specified age range. The documentation of PIV attempts and successes was reported by emergency medical service providers. This study was approved by an institutional review board. Results. Throughout the 101-month study period, there were 261,008 ambulance responses. PIV attempts were made in 4188 patients aged 18 years or younger. PIV placement was successful in 3699 patients (88.3%) and failed in 489 (11.7%). Age was significantly associated with success. Each 1-year increase in age was associated with an 11% increase in odds of PIV success (odds ratio, 1.11; 95% CI, 1.09–1.12; p < 0.001). Success was lowest in patients younger than 2 years old, with an overall success rate of 64.1% (141/220). Accounting for multiple attempts, success was achieved in 53.0% of attempts (141/266). Conclusions. Prehospital PIV attempts are uncommon (2% of emergent responses). Success rates are significantly associated with patient age in the pediatric population and lowest in those aged 2 years or less. Consideration of alternative forms of vascular access in this population may be beneficial. Key words: ambulance; emergency medical services; intraosseous; intravenous; pediatric

HYPOGLYCEMIA REQUIRING AMBULANCE SERVICES IN PATIENTS WITH TYPE 2 DIABETES IS ASSOCIATED WITH INCREASED LONG-TERM MORTALITY

OBJECTIVE To report population burden of hypoglycemia requiring ambulance services and long term outcomes thereafter, among people with type 2 diabetes (T2D). METHODS We retrieved all ambulance calls made by T2D for hypoglycemia in Olmsted County, Minnesota, between January 1, 2003, and December 31, 2009. RESULTS Seven hundred eighteen calls were made by 503 T2D (age 69 ± 12 years, 51% male), of which 328 (65%) were on insulin (INS), 54 (11%) on insulin + noninsulin agents (NIAI), 95 (19%) on sulphonylurea alone or in combination with other noninsulin agents (SFU), 21 (4%) on nonsulphonylurea noninsulin agents (NSFU), and 5 (1%) on no therapy (excluded from further analysis). NSFU had lower repeated calls (INS 25%, NIAI 26%, SFU 12%, NSFU 5%; P = .02), emergency room transportation (ERT) (INS 62%, NIAI 67%, SFU 68%, NSFU 38%; P = .06), and hospitalizations (INS 31%, NIAI 46%, SFU 38%, NSFU 19%; P = .02) compared to other groups. In multivariable mortality model, increased age (P<.001) was associated with an increased risk of death, whereas hypoglycemia predisposing comorbidities (chronic liver disease, end stage renal disease, adrenal insufficiency) (P = .06) were associated with a borderline increased risk, but no association was found with treatment group, repeated calls, ERT, hospitalization and baseline diabetic end organ complications. CONCLUSION To our knowledge, we report the first estimate of hypoglycemia requiring ambulance services among T2D, in contemporary clinical practice. NSFU cohort was associated with lower repeated calls, ERT, and hospitalizations compared to other therapeutic programs. Predictors of mortality post-hypoglycemia were age and hypoglycemia predisposing comorbidities.

Impact of Prehospital Electrocardiogram Protocol and Immediate Catheterization Team Activation for Patients With ST-Elevation–Myocardial Infarction

Guidelines recommend implementing prehospital electrocardiograms (PH ECG) into systems of care for patients with suspected ST-elevation–myocardial infarction to reduce door-to-balloon time (DTB). We developed a PH ECG protocol with an affiliated emergency medical service, combining 4 features: (1) PH ECG acquisition; (2) emergency medical service interpretation without PH ECG transmission; (3) prehospital activation of the cardiac catheterization team; and (4) emergency department bypass. We compared data from June 1, 2006, to August 31, 2007 (preimplementation group, n=50), with data from October 1, 2007, to June 30, 2010 (postimplementation group, n=82), analyzing all patients with ST-elevation–myocardial infarction transported by an affiliated EMS and treated with primary percutaneous coronary intervention. PH ECGs were acquired in 33 (66%) and 67 (82%) patients in the preimplementation and postimplementation groups, respectively ( P =0.041). Median DTB was 59 and 57 minutes for the preimplementation and postimplementation groups, respectively ( P =0.28). In a prespecified subgroup analysis of postimplementation patients (n=38) who had prehospital activation of catheterization team and emergency department bypass, median DTB was 32 minutes ( P <0.001 compared with preimplementation group). Our PH ECG protocol increased the frequency of PH ECG acquisition and decreased DTB for patients when all 4 features of our PH ECG protocol were carried out. Prehospital electrocardiograms (PH ECG) can decrease reperfusion times for patients with ST-elevation–myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).1–16 However, even when PH ECG are acquired, they may not be optimally utilized and integrated. A recent scientific statement by the American Heart Association (AHA) stated, “the central challenge for healthcare providers is not to simply perform PH ECG, but to use and integrate the diagnostic information from a PH ECG with systems of care.”17 The American College of Cardiology/AHA (ACC/AHA) guidelines for STEMI encourage a first medical contact-to-balloon time (FMCTB) within 90 …

Using prehospital electrocardiograms to improve door-to-balloon time for transferred patients with ST-elevation myocardial infarction: a case of extreme performance.

A 45-year-old man was walking his dog at 5:30 am in June 2009 and developed crushing 10/10 substernal chest pain. He called 911 at 6:05 am after his symptoms persisted for 35 minutes. Emergency medical services (EMS) paramedics arrived at the scene at 6:09 am and obtained a brief history and examination showing a diaphoretic man, pulse of 92 bpm, blood pressure of 170/140 mm Hg, normal respiratory rate, and no rales or murmurs. Treatment was initiated including supplemental oxygen, sublingual nitroglycerin, and aspirin. A 12-lead prehospital (PH) ECG was acquired at the scene at 6:16 am and interpreted by paramedics as showing acute ST-elevation myocardial infarction (STEMI) (Figure 1). On the basis of the PH ECG, paramedics made a single phone call to the closest community hospital emergency department and activated the PH ECG STEMI protocol at 6:17 am. The closest community hospital was located within 5 miles and did not have capability for percutaneous coronary intervention (PCI). The STEMI protocol activation consisted of autolaunching helicopter transport to intercept the patient at the community hospital and alerting the cardiac catheterization team at the tertiary PCI center located 50 miles away with the estimated patient arrival time. The patient arrived at the community hospital emergency department (door 1) by ground ambulance at 6:26 am. Helicopter transport picked up the patient and departed the community hospital at 6:37 am with a door 1 in–to–door 1 out time of 11 minutes. The patient arrived at the tertiary PCI center (door 2) at 7:10 am and was transported directly to the cardiac catheterization laboratory. During transport from the helipad to the cardiac catheterization laboratory, the patient had ventricular fibrillation in the elevator, and a shock was delivered with 120 J of selected energy. Coronary angiography showed a thrombotic occlusion of the …

Semiautomatic intraosseous devices in pediatric prehospital care.

Abstract Background. Intraosseous (IO) access is attempted when intravenous access cannot be established during an emergency. The U.S. Food and Drug Administration–cleared semiautomatic IO access device (EZ-IO; Vidacare Corp., Shavano Park, TX) has been shown to be safe and effective. Objective. To examine the characteristics of pediatric patients receiving IO infusions, primary clinical impressions of emergency medical services providers, success rates, and subsequent treatment after use of a manual IO device or the semiautomatic IO device. Methods. A midwestern, 12-site, statewide ambulance service began using the semiautomatic device instead of a manual IO device in 2007. Retrospective review included analysis of device placement rates and subsequent treatment of children (younger than 18 years) who underwent an IO access procedure with either the manual device (January 2003 through February 2007) or the semiautomatic device (March 2007 through May 2009). Results. First-attempt success was achieved in 80.6% of patients (25 of 31) in the manual device group and in 83.9% of patients (52 of 62) in the semiautomatic device group (p = 0.98). In the manual device group, there were 37 attempts for 25 successful device placements (67.6% success), and in the semiautomatic group, there were 72 attempts for 58 successful placements (80.6% success) (p = 0.52). Intravenous attempts were made before IO attempts in 35.5% of patients (11 of 31) in the manual group and in 1.7% of patients (1 of 60) in the semiautomatic group (p < 0.001). Treatment (medication use, excluding lidocaine for local anesthetic purposes and intravenous crystalloid) was administered IO in 84.0% of the patients (21 of 25) in the manual device group and in 73.2% of the patients (41 of 56) in the semiautomatic device group. Conclusions. For the pediatric cohort, use of a semiautomatic IO access device in place of a manual device offered no statistically significant difference in first-attempt success (3.3%) or in success per attempt (13.0%). However, the rate at which IO access was used by emergency medical services providers more than tripled with use of the semiautomatic device.

Effect of an onboard event recorder and a formal review process on ambulance driving behaviour

Background Onboard event recorders in vehicles record external and internal video before and after when preset g-force limits are exceeded. The use of these recorders in a fleet of ambulances, along with formal review, may decrease the number of unsafe driving events. The aim of this study was to evaluate the number of driving events since the inception of DriveCam technology in a fleet. Methods 54 vehicles were outfitted with DriveCam event recorders in 2003. Events were captured and assigned a categorical severity score of 1–4 (1 being the lowest severity) when the vehicle exceeded preset g-force limits. An event was assigned a score of ‘good’ if the review determined that the driver demonstrated good judgement. A review and feedback process was implemented in August 2006 and analysed through June 2008. Results During the study period, 2 979 891 miles were driven for 115 019 ambulance responses, with 6009 events captured. Events were categorised as follows: 2008 (33.4%) level 1; 3726 (62.0%) level 2; 175 (2.9%) level 3; 3 (0.05%) level 4; and 97 (1.6%) good events. The proportion of all events per mile and all events per response decreased over time with use of the recorder and review and feedback. Conclusions The institution of video event recorder technology along with formal review and feedback resulted in a change in driving behaviour. Given that call volumes increased and driving events decreased, these measures may serve as surrogates for improvements in safety and maintenance costs. Economic analysis is necessary for conclusions on fiscal impact.

Using Prehospital Electrocardiograms to Improve Door-to-Balloon Time for Transferred Patients With ST-Elevation Myocardial Infarction

A 45-year-old man was walking his dog at 5:30 am in June 2009 and developed crushing 10/10 substernal chest pain. He called 911 at 6:05 am after his symptoms persisted for 35 minutes. Emergency medical services (EMS) paramedics arrived at the scene at 6:09 am and obtained a brief history and examination showing a diaphoretic man, pulse of 92 bpm, blood pressure of 170/140 mm Hg, normal respiratory rate, and no rales or murmurs. Treatment was initiated including supplemental oxygen, sublingual nitroglycerin, and aspirin. A 12-lead prehospital (PH) ECG was acquired at the scene at 6:16 am and interpreted by paramedics as showing acute ST-elevation myocardial infarction (STEMI) (Figure 1). On the basis of the PH ECG, paramedics made a single phone call to the closest community hospital emergency department and activated the PH ECG STEMI protocol at 6:17 am. The closest community hospital was located within 5 miles and did not have capability for percutaneous coronary intervention (PCI). The STEMI protocol activation consisted of autolaunching helicopter transport to intercept the patient at the community hospital and alerting the cardiac catheterization team at the tertiary PCI center located 50 miles away with the estimated patient arrival time. The patient arrived at the community hospital emergency department (door 1) by ground ambulance at 6:26 am. Helicopter transport picked up the patient and departed the community hospital at 6:37 am with a door 1 in–to–door 1 out time of 11 minutes. The patient arrived at the tertiary PCI center (door 2) at 7:10 am and was transported directly to the cardiac catheterization laboratory. During transport from the helipad to the cardiac catheterization laboratory, the patient had ventricular fibrillation in the elevator, and a shock was delivered with 120 J of selected energy. Coronary angiography showed a thrombotic occlusion of the …