Prehospital Tradecraft refers to the methods, techniques and technologies employed in the delivery of modern professional level medical care in the prehospital environment, especially in cases of resuscitation. The art of resuscitation often calls for quick clinical decision making within a scope of practice, decisions made in light of unusual circumstances while stabilizing high acuity illness or injury in less than desirable surroundings.
This is the second installment of the Special Circumstances of Resuscitation series addressing various types of resuscitation cases that may be encountered by emergency medical personnel. The treatment recommendations reviewed herein correlate with recommendations taken from Part 3 of the American Heart Association’s 2020 ECC Guidelines, as well as recommendations from the National Association of Emergency Medical Technicians and other professional organizations that set our industry’s best practices.
First, let us define resuscitation as it pertains to emergency medicine. Resuscitation can be divided into two different categories, the peri-arrest phase(s) and the reanimation phase. The peri-arrest resuscitation phase includes both pre-arrest attempts at stabilization and post arrest stabilization following ROSC. The reanimation phase can be simply defined as the attempt to restore life including procedures and pharmacopoeia used to prevent or correct cardiopulmonary arrest from progressing to biological death. Successful stabilization during any phase of resuscitation can often be accomplished by addressing the causes of deterioration before cardiac arrest occurs or by addressing the origin of the cardiac arrest within the first 10 minutes of clinical death.
BLS Before ALS
Survival from high acuity medical events are dependent on quick recognition of life threats followed by immediate medical intervention. Survival depends on both ALS and BLS immediately utilizing standing-order interventions before global decompensation occurs, aka irreversible shock. For the clinically dead, rapid initiation of definitive BLS procedures (CPR) become the key to preventing biological death. It has been shown by several studies cited by the AHA, that survival from medical or traumatic cardiac arrest depends mostly on the skill set of the average EMR and basic EMT.1
There is no definitive proof that ALS procedures or measures makes any relevant difference during the reanimation phase of an OHCA. Furthermore, there is little data that shows any ALS medication regimen for cardiac arrest, including the serial administration of epinephrine, contributes to increased likelihood of a neurologically intact discharge from the hospital. The only measures that seem to improve OHCA resuscitation survival is the rapid initiation of CPR before EMS arrival, immediate bleeding control for catastrophic hemorrhage, uninterrupted high-quality compressions, and integration of an AED within the first few minutes of cardiac arrest.2
Paramedic care and advanced life support still plays an especially important yet unquantifiable role during reanimation, primarily as leaders of all resuscitation efforts in the EMS arena. Paramedic level ALS care during peri-arrest resuscitation is especially important if airway management is a concern or in cases where the use of vasopressors, antiarrhythmics, and fluid, can correct hypoperfusion and VQ mismatch. Though some predominantly BLS EMS systems have been shown to have higher survival rates from cardiac arrest, paramedics have a much broader scope of practice that gives them the ability to stabilize a patient, slow clinical deterioration in most circumstances, and in some cases, prevent clinical death.
Safety Second Resuscitation Practices?
Incredibly and surprisingly, the American Heart Association (AHA) still recommends the administration of mouth-based ventilation by healthcare professionals in certain situations like drowning, patients with tracheostomy tubes and pediatric cardiac arrest.2,3 Unfortunately, the recommendations for mouth-based procedures like mouth-to-stoma, don’t come with equal stress on the real-life consequences of contagious disease exposure during resuscitation. I understand that this is a touchy subject but the data regarding the number of health care workplace exposures since the mid-80s coupled with the hundreds of line-of-duty deaths (LODD) from this pandemic should leave no doubt the danger that emergency medical services face every day.
Over the last year, infectious disease has led to hundreds of documented first responder LODD illnesses and fatalities. 4, 5 As of March 2021, the AHA continues to teach and test mouth to barrier device ventilations as part of their healthcare professional training courses. High risk procedures like mouth-to-mask or mouth-to-mouth ventilations are contradictive of the title “healthcare professional” because professionals should never disregard the rules of body substance isolation. Given the data around workplace exposures over the last several decades, and the more recent COVID pandemic; has the time come for national organizations and regulatory agencies to reconsider recommendations around mouth-based procedures?”
The good news is that the 2020 AHA guidelines have recognized that compression only CPR (CO-CPR) has very similar and even improved survival rates when compared to CPR with integrated ventilations during OHCA.1 More data is needed for the AHA to take a more definitive stance on prioritizing CO-CPR over traditional CPR. It may also be time to stress high quality uninterrupted CO-CPR coupled with apneic ventilation by using passive oxygenation via NRB mask or high flow nasal cannula as a much safer alternative to CPR with any type of assisted ventilations without a definitive airway.6 The one thing that is definite is that prehospital clinicians and professional first responders should never use their mouth to perform any medical procedure. There is no cardiac arrest treatment plan that should ever require the provider to put their safety second and disregard the standard core rules of BSI precautions just to increase their chance of successful resuscitation and increase the statistics of any organization or association.
The Golden Hour
The first hour after a trauma is commonly known as “the Golden Hour,” a phrase first coined by Dr. R. Adams Cowley at the University of Maryland Medical Center in Baltimore in 1957. The term has inappropriately been used to gauge survival from traumatic cardiac arrest and even used to arbitrarily gauge survival for all cardiac arrests and high acuity injuries and illnesses. The Golden Hour no longer applies independently as a gauge to survival from high acuity traumatic injury because survival is dependent on several combined factors and none of the more relevant studies have 60 minutes as the dividing line for poor outcomes and good outcomes. For instance, one major frequently cited study showed that for every five-mile increment of distance from the scene to a level I or level II trauma center, the chances of survival from an acute injury decreased by approximately 8%7,which may indicate the time relevant distance from the trauma center is important but not 60 minute specific.
There are several more studies that lead off with the level of surgical care, specifically trauma Level 1 care, as the primary gauge for success with time and distance as lesser factors. Conversely, we know that traumatic cardiac arrest survival depends on duration of the arrest without ROSC, specifically with and without CPR before arrival of EMS, which appears to be more relevant to survival than time to a trauma center.10 Sustained traumatic cardiac arrest lasting more than 20 minutes without ROSC indicates that death is usually imminent.8, 10
If a patient who has suffered blunt traumatic injuries presents in cardiac arrest mortality can be well above 95%.11 Unfortunately, those trauma patients in cardiac arrest for more than 10 minutes without CPR, death is expectant and when followed by 10 minutes of CPR with no ROSC, death is assured 2,8, regardless of distance from a trauma center. Those trauma patients in cardiac arrest have considerably less time to be resuscitated successfully. These are just a few examples of why a specific 60-minute window cannot gauge probability of survival for out of hospital traumatic arrest. In most cases of refractory cardiopulmonary arrest, trauma or medical in origin, once we exceed the 20-minute mark without ROSC and the heart is in a non-shockable rhythm, reanimation efforts are considered futile 2,8 with 40 minutes left in the golden hour.
Anaphylactic Shock
Anaphylactic Reaction is a high-acuity life-threatening multi-system reaction to an allergen (threat.) There can be varied levels of response by the body’s immune system to remove an allergen from its systems and impede further allergens from entering. Specialized cells called basophils and mast cells release chemical mediators to defend against the allergen, the most prominent of the mediators released are histamines. During anaphylaxis, massive amounts of histamines are released and when they reach the body’s histamine receptor sites life-threating vasodilation, bronchoconstriction, and soft tissue edema may occur, singularly or combined. These responses are designed to stop the allergen from advancing systemically. In addition to abating the allergen from entering the system, anaphylaxis can also involve over production of tears, mucus, saliva, as well as digestive or GI distress such as nausea, vomiting, and diarrhea all designed to eject the allergen from the body.
The AHA stresses that airway compromise and poor perfusion should be the focus for all phases of resuscitation.2 EMT personnel should administer single dose inhalers and apply CPAP with PEEP if the airway is compromised by bronchoconstriction. Complete airway compromise should be expected if stridor is heard which makes supraglottic airway placement the last choice for airway management due to inability to bypass airway edema and ventilate adequately via the path of least resistance. For paramedics, a severely edematous airway requires definitive management leading to one of the few times that blind nasotracheal intubation may be indicated over DFI/RSI and if unsuccessful a surgical airway is the next logical airway intervention over any type of rescue airway.
Often time, the problems from anaphylaxis boils down to a ventilation/perfusion (VQ) mismatch, either the oxygen cannot get to the blood stream because of airway compromise or the blood cannot get to the oxygen or transport oxygen to vital tissues due to hypoperfusion. For the question of anaphylaxis induced VQ mismatch, Epinephrine is always the answer because of its dual bronchodilatory (beta II) and vasoconstrictive (alpha I) properties. Epinephrine should be administered first via the deep IM route butif an IV is available this is the preferable route of administration.2
One of our newest trends in ALS care used to combat hypoperfusion is the slow IV push administration of 1:100,000 (not a typo) epinephrine titrated to effect, this procedure is known as “push dose epi.” However, the AHA states that a continuous infusion of epinephrine (epi drip) along with isotonic fluid resuscitation is the preferred regimen to counter anaphylactic shock.2 Let’s not forget that Benadryl should also be administered early to impede the histamine cascade and steroids like solumedrol and Decadron should be considered to decrease the upper and lower airway tissue edema. A little vitamin Z (Zofran) never hurts and may take away the nausea and vomiting which is a combination of best practices and meticulous patient care.
Smoke Inhalation
The inhalation of toxic smoke and superheated air can lead to deadly airway compromise, ARDS and irreversible pulmonary damage secondary to burns or poisoning. The two most deadly toxins created by combustion is carbon monoxide (CO) resulting from incomplete combustion of natural fuel and Hydrogen Cyanide (HCN), which is the byproduct of burning synthetic material like pesticides, plastics, rubber, epoxy and fiberglass. Both CO and Hydrogen Cyanide impede the transfer of oxygen to tissues causing asphyxia.9 Cyanide specifically cripples the body’s ability to use oxygen at the cellular level, oxygen that is required to create ATP. Conversely, CO impedes O2 uptake by the red blood cells. Severe respiratory distress with normal SpO2 levels should be considered suspect as most oximeter devices will mistake the CO molecules for O2 molecules. CO-oximetry devices can be used to detect the presence of CO molecules on the red blood cells.
Any victim exposed to extreme heat and smoke should be suspect of airway problems until proven different. The initial assessment of a smoke inhalation victim should focus on the efficacy of mechanical respiration by auscultating lung sounds and visualization of the interior of the oropharynx. Resuscitation includes aggressive airway management with bronchodilators and high-flow oxygen via mask or high-flow cannula, the key to success is a high FiO2 especially for CO poisoning. The ALS provider should consider CPAP with PEEP in conjunction with inline beta II specific med-nebs for acute bronchoconstriction.9 For imminent airway failure secondary to upper airway edema, placement of a definitive airway via intubation is a must.
If intubation is unsuccessful, multiple attempts are deferred for immediate surgical airway procedures.10 In cases of airway burns, the placement of most types of rescue airways are not indicated because among other things, they cannot stop aspiration of extracellular fluids and secretions secondary to supraglottic tissue damage. Patients with airway burns should be transported to a burn center where they can receive the most definitive care. However, we realize these specialty centers aren’t at every street corner. If the airway cannot be managed in the field, the patient should be taken to the closest trauma center or emergency department.
Following toxic smoke inhalation, it is unlikely that paramedics will have the proper resources in the field to assess for the presence of HCN making prehospital diagnosis of cyanide toxicity dependent on a high index of suspicion. Any neurologic change, ALOC, or presentation of neurologic compromise such as seizures or cardiac arrest should be considered ominous signs of HCN poisoning or lethal CO toxicity.9 If HCN poisoning is suspected a cyanide antidote kit may be indicated. Cyanide antidote kits may contain amyl nitrite capsules and an intravenous infusion of Hydroxocobalamin. In some systems, the treatment of CO poisoning may include transport to a hyperbaric (dive) chamber but the efficacy of that specialty has not been proven in these types of cases, though the pathophysiological effects of that treatment make sense.
Be a Resuscitationist
In the early days of mobile intensive care, paramedics from some of the more aggressive EMS systems in the country like King County Medic One, Boston EMS, and Denver General (Health) were trained to be resuscitationists, experts at the art of maximally aggressive mobile patient care from scene-to-surgery. Although ALS care does not generally improve outcome from cardiac arrest, advanced procedures and pharmacological intervention can correct airway problems, improve oxygenation, and stabilize patients with inadequate tissue perfusion before they arrest. It is logical to assume that the ability to Identify and address unique cases of resuscitation will improve after every high acuity patient contact, regardless of survival. The longer a paramedic practices the art of resuscitation the better they become.
That said, every resuscitation should be viewed as a learning opportunity and approached as a teaching opportunity for field instructors and preceptors alike. The EMS provider should never defer from initial BLS procedures no matter the level of provider certification, it is always BLS before ALS. If EMS personnel become proficient at addressing the underlying causes leading to clinical destabilization, they can prevent digression to complete cardiopulmonary arrest, thus leading to improved clinical outcomes. Legitimate provider experience, clinical competency, quick utilization of relevant standing order protocols and unhindered field access to direct physician consult are all factors that can increase the likelihood of resuscitation success. When addressing unique high acuity cases that require active prehospital resuscitation, every level of provider must understand the various pathophysiological responses of the body and always consider the special circumstances that caused the cardiopulmonary arrest.
Resources and References
- Survival in Out-of-Hospital Cardiac Arrest After Standard Cardiopulmonary Resuscitation or Chest Compressions Only Before Arrival of Emergency Medical Services, Gabriel Riva, Mattias Ringh, Martin Jonsson. AHA Journal. October 2019 https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.118.038179
- 2020 AHA ECC Guidelines 2020-Part 3- Special Circumstances of Resuscitation-published via the web 8/2020 https://cpr.heart.org/en/resuscitation-science/cpr-and-ecc-guidelines/search-guidelines?searchText=special+situations#q=special%20situations&sort=relevancy
- 2010 AHA ECC Guidelines – Special Circumstances of Resuscitation, Section 12 https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.110.971069 ‘
- COVID-19 confirmed cases in public safety, local government, published April 4, 2020 https://www.gov1.com/coronavirus-covid-19/articles/covid-19-confirmed-cases-in-public-safety-local-government-cqEZLQNNSfS6RLnK/
- Officer Down Memorial Page, US LEO LODD. https://www.odmp.org/search/incident/covid-19
- Passive Ventilation- Passive oxygen flow better than assisted ventilations University Id Arizona School of Medicine https://opa.uahs.arizona.edu/newsroom/news/2009/cardiac-arrest-resuscitation-passive-oxygen-flow-better-assisted-ventilation
- Trauma Deserts: Distance From a Trauma Center, Transport Times, and Mortality From Gunshot Wounds in Chicago Am J Public Health. 2013 June; 103(6): 1103–1109 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3698742/
- EMS Termination Of Resuscitation And Pronouncement of Death C. Libby R. Skinner NCBI StatPearls published and updated 10/27/20 https://www.ncbi.nlm.nih.gov/books/NBK541113/
- CHEMM Chemical Hazard Emergency Medical Management Cyanide Poisoning as published 3/11/2021 https://chemm.nlm.nih.gov/cyanide_prehospital_mmg.htm#top
- Pre-Hospital Trauma Life Support 9th edition Published 2019. JBL PSG, ISBN 918-1-284-17147-1
- Trauma Survival meta-analysis Survival and neurologic outcome after traumatic out-of-hospital cardiopulmonary arrest in a pediatric and adult population: a systematic review. Journal of Critical Care Published online 2012 Jul 6. doi: 10.1186/cc11410 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3580693/
