Fluid management in traumatic shock: a practical approach for mountain rescue. Official recommendations of the International Commission for Mountain Emergency Medicine (ICAR MEDCOM)

Termination of Cardiopulmonary Resuscitation in Mountain Rescue: A Scoping Review and ICAR MedCom 2023 Recommendations

Lugnet, Viktor, Miles McDonough, Les Gordon, Mercedes Galindez, Nicolas Mena Reyes, Alison Sheets, Ken Zafren, and Peter Paal. Termination of cardiopulmonary resuscitation in mountain rescue: a scoping review and ICAR MedCom 2023 recommendations. High Alt Med Biol. 24:274-286, 2023. Background: In 2012, the International Commission for Mountain Emergency Medicine (ICAR MedCom) published recommendations for termination of cardiopulmonary resuscitation (CPR) in mountain rescue. New developments have necessitated an update. This is the 2023 update for termination of CPR in mountain rescue. Methods: For this scoping review, we searched the PubMed and Cochrane libraries, updated the recommendations, and obtained consensus approval within the writing group and the ICAR MedCom. Results: We screened a total of 9,102 articles, of which 120 articles met the inclusion criteria. We developed 17 recommendations graded according to the strength of recommendation and level of evidence. Conclusions: Most of the recommendations from 2012 are still valid. We made minor changes regarding the safety of rescuers and responses to primary or traumatic cardiac arrest. The criteria for termination of CPR remain unchanged. The principal changes include updated recommendations for mechanical chest compression, point of care ultrasound (POCUS), extracorporeal life support (ECLS) for hypothermia, the effects of water temperature in drowning, and the use of burial times in avalanche rescue.

Multifactorial Shock: A Neglected Situation in Polytrauma Patients

Background: Shock after traumatic injury is likely to be hypovolemic, but different types of shock (distributive shock, obstructive shock, or cardiogenic shock) can occur in combination, known as multifactorial shock. Multifactorial shock is a neglected area of study, and is only reported sporadically. Little is known about the incidence, characteristics, and outcomes of multifactorial shock after polytrauma. Methods: A retrospective, observational, multicenter study was conducted in four Level I trauma centers involving 1051 polytrauma patients from June 2020 to April 2022. Results: The mean Injury Severity Score (ISS) was 31.1, indicating a severely injured population. The most common type of shock in the early phase after polytrauma (≤48 h) is hypovolemic shock (83.2%), followed by distributive shock (14.4%), obstructive shock (8.7%), and cardiogenic shock (3.8%). In the middle phase after polytrauma (>48 h or ≤14 days), the most common type of shock is distributive shock (70.7%), followed by hypovolemic shock (27.2%), obstructive shock (9.9%), and cardiogenic shock (7.2%). Multifactorial shock accounted for 9.7% of the entire shock population in the early phase and 15.2% in the middle phase. In total, seven combinations of multifactorial shock were described. Patients with multifactorial shock have a significantly higher complication rate and mortality than those with single-factor shock. Conclusions: This study characterizes the incidence of various types of shock in different phases after polytrauma and emphasizes that different types of shock can occur simultaneously or sequentially in polytrauma patients. Multifactorial shock has a relatively high incidence and mortality in polytrauma patients, and trauma specialists should be alert to the possibility of their occurrence.

Multiple trauma management in mountain environments - a scoping review : Evidence based guidelines of the International Commission for Mountain Emergency Medicine (ICAR MedCom). Intended for physicians and other advanced life support personnel

Background

Multiple trauma in mountain environments may be associated with increased morbidity and mortality compared to urban environments.

Objective

To provide evidence based guidance to assist rescuers in multiple trauma management in mountain environments.

Eligibility criteria

All articles published on or before September 30th 2019, in all languages, were included. Articles were searched with predefined search terms.

Sources of evidence

PubMed, Cochrane Database of Systematic Reviews and hand searching of relevant studies from the reference list of included articles.

Charting methods

Evidence was searched according to clinically relevant topics and PICO questions.

Results

Two-hundred forty-seven articles met the inclusion criteria. Recommendations were developed and graded according to the evidence-grading system of the American College of Chest Physicians. The manuscript was initially written and discussed by the coauthors. Then it was presented to ICAR MedCom in draft and again in final form for discussion and internal peer review. Finally, in a face-to-face discussion within ICAR MedCom consensus was reached on October 11th 2019, at the ICAR fall meeting in Zakopane, Poland.

Conclusions

Multiple trauma management in mountain environments can be demanding. Safety of the rescuers and the victim has priority. A crABCDE approach, with haemorrhage control first, is central, followed by basic first aid, splinting, immobilisation, analgesia, and insulation. Time for on-site medical treatment must be balanced against the need for rapid transfer to a trauma centre and should be as short as possible. Reduced on-scene times may be achieved with helicopter rescue. Advanced diagnostics (e.g. ultrasound) may be used and treatment continued during transport.

Accuracy of low-weight versus standard syringe infusion pump devices depending on altitude

Background

Intravenous drug infusions in critically ill patients require accurate syringe infusion pumps (SIPs). This is particularly important during transportation of critically ill patients by helicopter emergency medical services (HEMS), where altitude may influence device performance. Because weight is a real concern in HEMS, new low-weight devices are very appealing.

The aim of this study was to compare infusion flow rates delivered by low-weight versus standard SIP devices, in the prehospital emergency medicine setting, at different altitudes.

Methods

We conducted a comparative bench study involving five SIP devices (two standard and three low-weight models) at 300, 1700 and 3000 m altitude. The primary endpoint was the flow rate delivered by SIPs for prespecified values. We used two methods to measure flow. The normative method consisted in measuring weight (method A) and the alternate method consisted in measuring instantaneous flow (method B).

Results

Using method A, no significant differences were found in median flow rates and interquartile range depending on device and altitude for a prespecified 10-mL/h flow. However, method B showed that low-weight SIPs delivered multiple sequential boluses with substantial variations (1.2–15.8 mL/h) rather than a prespecified continuous 5-mL/h flow. At 1700 m altitude, the interquartile range of delivered flows increased only for low-weight devices (p for interaction< 0.001).

Conclusions

Despite satisfactory normative tests, low-weight SIPs deliver discontinuous flow with potential clinical implications for critically ill patients receiving vasoactive drugs. This study also highlights a thus far unknown negative impact of altitude on SIP function. We believe that normative requirements for SIP approval should be revised accordingly.

Physician staffed helicopter emergency medical systems can provide advanced trauma life support in mountainous and remote areas

INTRODUCTION

In remote and mountainous areas, helicopter emergency medical systems (HEMS) are used to expedite evacuation and provide pre-hospital advanced trauma life support (ATLS) in major trauma victims. Aim of the study was to investigate feasibility of ATLS in HEMS mountain rescue missions and its influence on patient condition at hospital admission.

PATIENTS

58 major trauma victims (Injury Severity Score ≥16), evacuated by physician staffed HEMS from remote and mountainous areas in the State of Tyrol, Austria between 1.1.2011 and 31.12.2013.

RESULTS

Pre-hospital time exceeded 90min in 24 (44%) cases. 31 (53%) patients suffered critical impairment of at least one vital function (systolic blood pressure <90mmHg, GCS <10, or respiratory rate <10 or >30). 4 (6.9%) of 58 patients died prior to hospital admission. Volume resuscitation was restrictive: 18 (72%) of 25 hypotensive patients received ≤500ml fluids and blood pressure was increased >90mmHg at hospital admission in only 9 (36%) of these 25 patients. 8 (50%) of 16 brain trauma patients with a blood pressure <90mmHg remained hypotensive at hospital admission. Endotracheal intubation was accomplished without major complications in 15 (79%) of 19 patients with a Glasgow Coma Scale score <10. Rope operations were necessary in 40 (69%) of 58 cases and ATLS was started before hoist evacuation in 30 (75%) of them.

CONCLUSIONS

The frequent combination of prolonged pre-hospital times, with critical impairment of vital functions, supports the need for early ATLS in HEMS mountain rescue missions. Pre-hospital endotracheal intubation is possible with a high success and low complication rate also in a mountain rescue scenario. Pre-hospital volume resuscitation is restrictive and hypotension is reversed at hospital admission in only one third of patients. Prolonged pre-hospital hypotension remains an unresolved problem in half of all brain trauma patients and indicates the difficulties to increase blood pressure to a desired level in a mountain rescue scenario. Despite technical considerations, on-site ATLS is feasible for an experienced emergency physician in the majority of rope rescue operations.

Prehospital fluid resuscitation in hypotensive trauma patients: do we need a tailored approach?

AIM

The ideal strategy for prehospital intravenous fluid resuscitation in trauma remains unclear. Fluid resuscitation may reverse shock but aggravate bleeding by raising blood pressure and haemodilution. We examined the effect of prehospital i.v. fluid on the physiologic status and need for blood transfusion in hypotensive trauma patients after their arrival in the emergency department (ED).

METHODS

Retrospective analysis of trauma patients (n=941) with field hypotension presenting to a level 1 trauma centre. Regression models were used to investigate associations between prehospital fluid volumes and shock index and blood transfusion respectively in the emergency department and mortality at 24h.

RESULTS

A 1L increase of prehospital i.v. fluid was associated with a 7% decrease of shock index in the emergency department (p<0.001). Volumes of 0.5-1L and 1-2L were associated with reduced likelihood of shock as compared to volumes of 0-0.5L: OR 0.61 (p=0.03) and OR 0.54 (p=0.02), respectively. Volumes of 1-2L were also associated with an increased likelihood of receiving blood transfusion in ED: OR 3.27 (p<0.001). Patients who had received volumes of >2L have a much greater likelihood of receiving blood transfusion in ED: OR 9.92 (p<0.001). Mortality at 24h was not associated with prehospital i.v. fluids.

CONCLUSION

In hypotensive trauma patients, prehospital i.v. fluids were associated with a reduction of likelihood of shock upon arrival in ED. However, volumes of >1L were associated with a markedly increased likelihood of receiving blood transfusion in ED. Therefore, decision making regarding prehospital i.v. fluid resuscitation is critical and may need to be tailored to the individual situation. Further research is needed to clarify whether a causal relationship exists between prehospital i.v. fluid volume and blood transfusion. Also, prospective trials on prehospital i.v. fluid resuscitation strategies in specific patient subgroups (e.g. traumatic brain injury and concomitant haemorrhage) are warranted.

HEMS in Slovenia: one country, four models, different quality outcomes

OBJECTIVE

The objective of this study was to determine the quality of patient care using quality indicators in 4 different Slovenian helicopter emergency medical service (HEMS) models.

METHODS

This was a cross-sectional study of all 4 HEMS in Slovenia. We collected data on quality for the period from July 2003 to August 2008, in a sample of all eligible patients that were managed by HEMS during the study period (N = 833). We obtained the following data on emergency operations: the time and organizational features of the operation; the description of the patients' condition; and the on-site diagnostic and treatment procedures. We used the following as quality indicators: the number of resuscitated patients that were intubated; the number of patients with a Glasgow Coma Scale (GCS) score of # 8 that were intubated; the number of patients with acute coronary syndrome that received treatment with morphine, oxygen, nitroglycerine, and aspirin (MONA); the number of patients with a National Advisory Committee on Aeronautics (NACA) scale score of $ 4 with an intravenous line; the number of patients with a NACA score of $ 5 that were given oxygen; and the number of patients with a NACA score of $ 4 that were given appropriate analgesic treatment.

RESULTS

Across all HEMS bases, 36 (87.8%) resuscitated patients were intubated; 122 (81.9%) patients with GCS # 8 were intubated; 149 (89.2%) patients with ACS were given MONA treatment; 52 (92.9%) patients with a NACA score of $ 4 were given an intravenous line; 254 (92.7%) patients with a NACA score of $ 5 were given oxygen; and 18 (32.7%) trauma patients with a NACA score of $ 4 were given intravenous analgesics. The quality of patient management in HEMS in Slovenia is affected by the callout procedure, the presence or absence of a fixed rope, the type of helicopter operator, and the provider of the doctor in the helicopter team.

CONCLUSIONS

The data from our study indicates that the quality of patient management in HEMS in Slovenia is high. It also seems that organizational factors play a role in the quality management of patients in HEMS as well, but their effect remains unclear and needs further evaluation.

Walking between the drops: Israeli defense forces' fluid resuscitation protocol

BACKGROUND

Current research in trauma resuscitation indicates that it is important to strike a balance between withholding intravenous fluid therapy, on one hand, and giving too much, on the other. The Israel Defense Forces' former protocol for prehospital fluid administration in the trauma setting was intended to navigate this balancing act. It turned out that the protocol was not being appropriately implemented in field conditions.

OBJECTIVES

We describe our process improvement, which resulted in our revised protocol. Our goal in drafting the new protocol was to achieve yet another balance, this time between the recommendations derived from accumulating science, and the efficacy with which they could likely be implemented in the field.

DISCUSSION

We review the available research in prehospital fluid administration, and then develop our current protocol. Per our a priori requirements, the protocol is unified in that medical personnel from a very wide spectrum of caregivers can apply it; and it is appropriate for both short evacuation time scenarios (e.g., low-intensity conflicts) and lengthier evacuation scenarios (e.g., high-intensity conflicts).

CONCLUSION

Survival is likely improved if guidelines do not add unnecessary complexity and are easily implemented. We believe that the current protocol is suitable for the large majority of trauma patients, and helps guide providers toward a primary decision-point regarding fluid administration. Nonetheless, as long as only coarse clinical parameters for identifying shock are available, and data regarding optimal treatment are conflicting, offering truly balanced fluid resuscitation guidelines is a lot like walking between the drops.

Medical standards for mountain rescue operations using helicopters: official consensus recommendations of the International Commission for Mountain Emergency Medicine (ICAR MEDCOM)

The purpose of this article is to establish medical recommendations for safe and effective Helicopter Emergency Medical Systems (HEMS) in countries with a dedicated mountain rescue service. A nonsystematic search was undertaken and a consensus among members of International Commission for Mountain Emergency Medicine (ICAR Medcom) was reached. For the severely injured or ill patient, survival depends on approach time and quality of medical treatment by high-level providers. Helicopters can provide significant shortening of the times involved in mountain rescue. Safety is of utmost importance and everything possible should be done to minimize risk. Even in the mountainous environment, the patient should be reached as quickly as possible (optimally<20 min) and provided with on-site and en-route medical treatment according to international standards. The HEMS unit should be integrated into the Emergency Medical System of the region. All dispatchers should be aware of the specific problems encountered in mountainous areas. The nearest qualified HEMS team to the incident site, regardless of administrative boundaries, should be dispatched. The 'air rescue optimal crew' concept with its flexibility and adaptability of crewmembers ensures that all HEMS tasks can be performed. The helicopter and all equipment should be appropriate for the conditions and specific for mountain related emergencies. These recommendations, agreed by ICAR Medcom, establish recommendations for safe and effective HEMS in mountain rescue.