Craig Manifold

No Deaths Associated with Patient Refusal of Transport After Naloxone-Reversed Opioid Overdose

Abstract Introduction. Naloxone is widely used in the treatment and reversal of opioid overdose. Most emergency medical services (EMS) systems administer naloxone by standing order, and titrate only to reverse respiratory depression without fully reversing sedation. Some EMS systems routinely administer sufficient naloxone to fully reverse the effects of opioid overdose. Frequently patients refuse further medical evaluation or intervention, including transport. Objectives. The purpose of this study was to evaluate the safety of this practice and determine whether increased mortality is associated with full reversal of opioids. As a component of a comprehensive quality assurance initiative, we assessed mortality during the 48 hours after patients received naloxone to reverse opioid overdose followed by patient-initiated refusal of transportation. Methods. The setting was a large urban fire-based EMS system. Investigators provided the Bexar County Medical Examiners Office (MEO) with a list of patients who were treated by the San Antonio Fire Department with naloxone, and not transported. Inclusion criteria were administration of naloxone and patient-initiated refusal. Patient dispositions also included aid only, referral to the MEO, or referral to law enforcement. The list was then compared with the MEO database. A chart review was completed on all patients treated and subsequently presented to the MEO within two days. A secondary time period of 30 days was also assessed. Results. The list identified 592 patients treated with naloxone and not transported to the emergency department. Five-hundred fifty-two patients received naloxone and refused transport or were not transported. The remaining 40 patients all presented to EMS in cardiac arrest, naloxone was administered during the course of resuscitation, and subsequent efforts were terminated in the field. None of the patients receiving naloxone with a subsequent patient-initiated refusal were examined at the MEO within the two-day end point. The 30-day assessment revealed that nine individuals were treated with naloxone and subsequently died, but the shortest time interval between date of service and date of death was four days. Conclusion. The primary outcome was that no patients who were treated with naloxone for opioid overdose and then refused care were examined by the MEO within a 48-hour time frame.

Cardiac Arrest Survival Is Rare Without Prehospital Return of Spontaneous Circulation

Abstract Background. Emergency medical services (EMS) are crucial in the management of out-of-hospital cardiac arrest (OHCA). Despite accepted termination-of-resuscitation criteria, many patients are transported to the hospital without achieving field return of spontaneous circulation (ROSC). Objective. We examine field ROSC influence on OHCA survival to hospital discharge in two large urban EMS systems. Methods. A retrospective analysis of prospectively collected data was conducted. Data collection is a component of San Antonio Fire Departments comprehensive quality assurance/quality improvement program and Cincinnati Fire Departments participation in the Cardiac Arrest Registry to Enhance Survival (CARES) project. Attempted resuscitations of medical OHCA and cardiac OHCA for San Antonio and Cincinnati, respectively, from 2008 to 2010 were analyzed by city and in aggregate. Results. A total of 2,483 resuscitation attempts were evaluated. Age and gender distributions were similar between cities, but ethnic profiles differed. Cincinnati had 17% (p = 0.002) more patients with an initial shockable rhythm and was more likely to initiate transport before field ROSC. Overall survival to hospital discharge was 165 of 2,483 (6.6%). More than one-third (894 of 2,483, 36%) achieved field ROSC. Survival with field ROSC was 17.2% (154 of 894) and without field ROSC was 0.69% (11 of 1,589). Of the 11 survivors transported prior to field ROSC, nine received defibrillation by EMS. No asystolic patient survived to hospital discharge without field ROSC. Conclusion. Survival to hospital discharge after OHCA is rare without field ROSC. Resuscitation efforts should focus on achieving field ROSC. Transport should be reserved for patients with field ROSC or a shockable rhythm.

Capnography for the Nonintubated Patient in the Emergency Setting

BACKGROUND Multiple studies illustrate the benefits of waveform capnography in the nonintubated patient. This type of monitoring is routinely used by anesthesia providers to recognize ventilation issues. Its role in the administration of deep sedation is well defined. Prehospital providers embrace the ease and benefit of monitoring capnography. Currently, few community-based emergency physicians utilize capnography with the nonintubated patient. OBJECTIVE This article will identify clinical areas where monitoring end-tidal carbon dioxide is beneficial to the emergency provider and patient. DISCUSSION Capnography provides real-time data to aid in the diagnosis and patient monitoring for patient states beyond procedural sedation and bronchospasm. Capnographic changes provide valuable information in such processes as diabetic ketoacidosis, seizures, pulmonary embolism, and malignant hyperthermia. CONCLUSIONS Capnography is a quick, low-cost method of enhancing patient safety with the potential to improve the clinicians diagnostic power.

Promoting early diagnosis of hemodynamic instability during simulated hemorrhage with the use of a real-time decision-assist algorithm

BACKGROUND This study aimed to test the hypothesis that the addition of a real-time decision-assist machine learning algorithm by emergency medical system personnel could shorten the time needed to identify an unstable patient during a hemorrhage profile as compared with vital sign information alone. METHODS Fifty emergency medical team-paramedics from a large, urban fire department participated as subjects. Subjects viewed a monitor screen on two occasions as follows: (1) display of standard vital signs alone and (2) with the addition of an index (Compensatory Reserve Index) associated with estimated central blood volume status. The subjects were asked to push a computer key at any point in the sequence they believed the patient had become unstable based on information provided by the monitor screen. The average difference in time to identify hemodynamic instability between experimental and control groups was assessed by paired, two-tailed t test and reported with 95% confidence intervals (95% CI). RESULTS The mean (SD) amount of time required to identify an unstable patient was 18.3 (4.1) minutes (95% CI, 17.2–19.4 minutes) without the algorithm and 10.7 (4.2) minutes (95% CI, 9.5–11.9 minutes) with the algorithm (p < 0.001). CONCLUSION In a simulated patient encounter involving uncontrolled hemorrhage, the use of a monitor that estimates central blood volume loss was associated with early identification of impending hemodynamic instability. Physiologic monitors capable of early identification and estimation of the physiologic capacity to compensate for blood loss during hemorrhage may enable optimal guidance for hypotensive resuscitation. They may also help identify casualties benefitting from forward administration of plasma, antifibrinolytics and procoagulants in a remote damage-control resuscitation model.

The Remote Trauma Outcomes Research Network: Rationale and Methodology for the Study of Prolonged Out-of-hospital Transport Intervals on Trauma Patient Outcome

Abstract : The time elapsed between injury and hemostasis is inversely proportional to survival and functional recovery in the trauma patient.1,2 Yet, we remain largely naBve to the pathophysiologic sequence that unfolds during this critical time frame.3,4 Likewise, prolonged evacuations encountered by critically wounded combatants may pose similar hazards. Little room for improvement remains in hospital-based care, however,when one considers the 97% survival rate for casualties engaged by the Joint Trauma System.5 In contrast, the out-of-hospital and preoperative phase of care (referred to asNATORole I) represent perhaps our greatest opportunity to further reduce combat death.6,7 Ironically, many of the greatest advances in medical and surgical practice have occurred as a consequence of armed conflict. The impending resolution of contemporary conflicts in Iraq and Afghanistan is awelcome development, but with it will come a loss of the opportunity to observe, learn, and innovate while engaged in combat casualty care. Thus, if advances are to continue, it will be necessary to refocus existing clinical investigation networks engaged in battlefield care research and to seek a relevant setting other than war to continue this vital effort. The Remote Trauma Outcomes Research Network (Rem TORN) is the first and largest investigation to date of trauma patients undergoing prolonged preoperative treatment and transport. By providing a model complementary to the current deployed environment in terms of geospatial, temporal, and scope-of-practice characteristics, itmay enable rigorous and relevant studies of out-of-hospital care, new diagnostic and therapeutic approaches, and their collective effect on outcomes. Ultimately, it may enable the establishment of remote damage control resuscitation (RDCR) as a clinical practice.

A Randomized, Controlled Trial Comparing Arteriovenous to Venovenous Rewarming of Severe Hypothermia in a Porcine Model

BACKGROUND The purpose of this study was to evaluate active rewarming using continuous arteriovenous rewarming (CAVR) and continuous venovenous rewarming (CVVR) methods during severe hypothermia using an electromagnetic fluid warmer. Rapid rewarming using these techniques is superior to passive rewarming and is possible with commercially available equipment. METHODS Eighteen swine (55-65 kg) were assigned to CAVR, CVVR, or control. Vascular access was obtained via central lines (8.5-French) in all subjects. Subjects were cooled to 27 degrees C (80.6 degrees F) in an ice bath, and then dried, covered, and connected to the rewarming device. The carotid artery (CAVR) or internal jugular vein (CVVR) was used for circuit inflow. Warmed 39 degrees C (102.2 degrees F) blood was returned via the femoral vein. Hemodynamic parameters and temperatures (pulmonary artery and rectal) were recorded until reaching an endpoint of a pulmonary artery temperature of 37 degrees C (98.6 degrees F). RESULTS Mean rewarming time in the CAVR group was 2 hours 14 minutes, with a mean rewarming rate of 4.5 degrees C/h (8.1 degrees F/h, 0.034 degrees C/kg/h). Total circulating volume averaged 65 L. CVVR averaged 3 hours 8 minutes, with a mean rewarming rate of 3.2 degrees C/h (5.8 degrees F/h, 0.024 degrees C/kg/h). Total circulating volume averaged 67 L. Controls averaged 10 hours 42 minutes, with a mean rate of 0.9 degrees C/h (1.7 degrees F/h, 0.007 degrees C/kg/h). The CAVR group was faster than the CVVR group in both the rewarming rate and total time to rewarming (p = 0.034 and p = 0.040, respectively). Both experimental groups were significantly different from controls in rewarming rate and total time to rewarming (p < 0.001). CONCLUSION CAVR offers the most rapid rate of rewarming. CVVR offers a rapid rate using less invasive procedures. Both techniques are markedly superior to passive rewarming methods typically used during early resuscitation.

A randomized control hands-on defibrillation study-Barrier use evaluation

INTRODUCTION Chest compressions and defibrillation are the only therapies proven to increase survival in cardiac arrest. Historically, rescuers must remove hands to shock, thereby interrupting chest compressions. This hands-off time results in a zero blood flow state. Pauses have been associated with poorer neurological recovery. METHODS This was a blinded randomized control cadaver study evaluating the detection of defibrillation during manual chest compressions. An active defibrillator was connected to the cadaver in the sternum-apex configuration. The sham defibrillator was not connected to the cadaver. Subjects performed chest compressions using 6 barrier types: barehand, single and double layer nitrile gloves, firefighter gloves, neoprene pad, and a manual chest compression/decompression device. Randomized defibrillations (10 per barrier type) were delivered at 30 joules (J) for bare hand and 360J for all other barriers. After each shock, the subject indicated degree of sensation on a VAS scale. RESULTS Ten subjects participated. All subjects detected 30j shocks during barehand compressions, with only 1 undetected real shock. All barriers combined totaled 500 shocks delivered. Five (1%) active shocks were detected, 1(0.2%) single layer of Nitrile, 3(0.6%) with double layer nitrile, and 1(0.2%) with the neoprene barrier. One sham shock was reported with the single layer nitrile glove. No shocks were detected with fire gloves or compression decompression device. All shocks detected barely perceptible (0.25(±0.05)cm on 10cm VAS scale). CONCLUSIONS Nitrile gloves and neoprene pad prevent (99%) responders detection of defibrillation of a cadaver. Fire gloves and compression decompression device prevented detection.

Use of an impedance threshold device in spontaneously breathing patients with hypotension secondary to trauma: An observational cohort feasibility study

BACKGROUND An impedance threshold device (ITD) intended for use in the spontaneously breathing patient has been shown to raise blood pressure in hypotensive patients. This device has not been evaluated in patients with hypotension secondary to trauma. This study focused on changes in key vital signs when the ITD was added to the paramedic treatment protocol for hypotensive patients with prehospital traumatic injury. METHODS A 6-month prospective nonrandomized observational cohort study was conducted of 200 spontaneously breathing symptomatic adult patients with prehospital hypotension due to multiple causes; the patients of primary interest experienced a traumatic injury. Upon determination of hypotension (systolic blood pressure of approximately ⩽90 mm Hg), standard therapy was initiated by application of the mask-style ITD. Vital signs were documented every 2 minutes to 5 minutes after intervention. A change in mean arterial pressure (MAP) with ITD use was the primary study endpoint. RESULTS Of the 200 hypotensive subjects treated, 29 (3 were excluded because of incomplete data sets and 3 patients treated with the ITD were excluded because their blood pressure did not meet inclusion criterion) were hypotensive secondary to trauma. Their MAP increased from 60 mm Hg (SD, 11 mm Hg; 95% confidence interval [CI], 8.17–15.432) to 78 mm Hg (16 mm Hg; 95% CI, 12.43–23.46) (p = 0.001), without significant change in mean heart rate. Approximately 75% of the patients reported moderate to easy tolerance. Similar increases in MAP were observed in the nontraumatic patients, from 60 mm Hg (10 mm Hg; 95% CI, 9.4–11.5) to 70 (15; 95% CI, 13.4–16.7) (p = 0.0001). CONCLUSION In this observational cohort study of patients with hypotension secondary to trauma, the ITD was well tolerated, and MAP as well as systolic and diastolic blood pressure were improved. The patients were not overresuscitated with this intervention. On the basis of these findings, additional studies in patients with hypotension secondary to traumatic injury should be performed to better define the need and benefit of additional fluid resuscitation when the ITD is used. LEVEL OF EVIDENCE Therapeutic study, level IV.