Page 77 - JSOM Summer 2025

BOX 1 Readily Available Drowning, Hypothermia, and Critical Care Management Resources
• Tactical Combat Casualty Care (TCCC) Guidelines – available at: https://books.allogy.com/web/tenant/8/books/b729b76a-1a34-4bf7-
20
b76b-66bb2072b2a7/
• Prolonged Casualty Care Guidelines – available at: https://jts.health.mil/assets/docs/cpgs/Prolonged_Casualty_Care_Guidelines_21_Dec_
30
2021_ID91.pdf
3
• Drowning Management – available at: https://jts.health.mil/assets/docs/cpgs/Drowning_Management_27_Oct_2017_ID64.pdf
17
• Hypothermia Prevention and Treatment – available at: https://jts.health.mil/assets/docs/cpgs/Hypothermia_Prevention_Treatment_07_
Jun_2023_ID23.pdf
• Acute Respiratory Failure – available at: https://jts.health.mil/assets/docs/cpgs/Acute_Respiratory_Failure_23_Jan_2017_ID06.pdf
34
• Airway Management in Prolonged Field Care – available at: https://jts.health.mil/assets/docs/cpgs/Airway_Management_in_Prolonged_
31
Field_Care_01_May_2020_ID80.pdf
39
• Telemedicine Guidance in the Deployed Setting – available at: https://jts.health.mil/assets/docs/cpgs/Telemedicine_Deployed_Setting_19_
Sep_2023.pdf
47
• Documentation In Prolonged Field Care – available at: https://jts.health.mil/assets/docs/cpgs/Documentation_Prolonged_Field_Care_13_
Nov_2018_ID72.pdf
• Management of Drowned Patient – available electronically through Naval Medical Center San Diego Library Services
2
• Management of hypothermia and immersion injuries – available electronically through Naval Medical Center San Diego Library Services
16
• Acute Respiratory Failure and Ventilator Management Afloat – available electronically through Naval Medical Center San Diego Library
42
Services
48
• Maritime Prolonged Casualty Care – available electronically through Naval Medical Center San Diego Library Services
46
• Infectious Disease Pearls for Maritime Surgical Teams – available electronically through Naval Medical Center San Diego Library Services
Patient 1 did not experience any trauma, likely helping con- maritime caregivers should discuss the procedure with experi-
tribute to the lack of severe hypothermia and fluid aspiration. enced critical care nurses and physicians via synchronous or
He was able to be treated conservatively using oral hydration asynchronous telemedicine modalities before proceeding.
and passive warming methods, with active body warmers only
being used to expedite his improvement. When at all possible, Cardiopulmonary arrest was not experienced in the above
this method of treatment should be used, as any more invasive cases but should be considered as it requires significant nuance
medical treatment increases the risk of potential morbidity and in the hypothermic patient. Due to multiple anecdotal cases
mortality. of neurologic preservation even after prolonged unconscious
(and likely time in arrest) periods in water, particularly colder
Patient 2 suffered some type of traumatic brain injury without water, CPR should be continued until patients warm at mini-
evidence of skull fracture, a closed long bone fracture of the mum to an increase in 5°C, but ideally until they reach 32°C.
upper extremity, and aspiration pneumonitis with subsequent Previous literature has shown that cerebral oxygen consump-
severe ARDS from drowning. The humerus fracture did not tion decreases 5% for every 1°C drop in body temperature.
alter the course of the patient’s care significantly, but the con- Many medications, and even defibrillators, will not work until
3
cern for a possible head injury was considered early in the pa- the patient is at least 30°C. The American Heart Association
tient’s care, and serial neurologic monitoring was performed. (AHA) recommends attempting one defibrillation for patients
The patient experienced what is very common in these types <30°C in pulseless ventricular tachycardia or ventricular fibril-
of situations, severe ARDS secondary to what was probably a lation, and if it does not work to cease further attempts until
large amount of seawater aspiration and concomitant hypo- the patient is warmer than 30°C. 48,49
thermia. The hypothermia resolved appropriately after simple
measures, such as drying the patient and using a forced air Another notable pathology not experienced in the above cases
warming blanket. The course of slowly worsening hypoxia but should be considered by any provider caring for a large
and lung compliance resulting in extremely high levels of FIO volume fluid aspiration patient is the potential for electrolyte
2
and PEEP is not unexpected in these patients, but the mortality shifts and disturbances. It typically does not occur except in
risk was very high in this hypothetical patient—at least 42%— locations with very high levels of electrolytes, such as the Dead
using the Berlin criteria estimated the PaO /FIO ratio, using Sea. Hypercalcemia and hypermagnesemia are the two elec-
2
2
SpO /FIO ratios as surrogate. Given the traumatic mechanism trolyte disturbances that may require treatment, making both
2
2
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and the barotrauma, pneumothorax must always be a concern, mandatory testing parameters when available. Hyponatre-
particularly with a rapid change respiratory status. mia has been postulated as a major concern after significant
freshwater aspiration, and while studies have shown patients
At a more robust tertiary care hospital, a patient with this se- are in fact hyponatremic after such an incident, it is often more
vere lung injury would almost certainly require more advanced mild than anticipated, and patients have rarely experienced
ventilatory modes, bronchoscopy with bronchoalveolar la- hyponatremic seizures or other sequelae. Furthermore, re-
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vage, and possibly ECMO. ARDSnet lung protective strategies gardless of either fresh water or salt water aspiration, drown-
are critical to supporting this lung injury until evacuation is ing survivors typically are unable to aspirate enough water to
possible, while avoiding further complications such as baro- cause electrolyte disturbances. 2,3
trauma and pneumothorax.
This scenario has several training, skills sustainment, and med-
Proning was used in this scenario. It should be noted that on an ical supply implications. If an Independent Duty Corpsman
LPD there are no nurses of any kind, nor physicians with any embarked on smaller naval vessel, such as a destroyer, cruiser,
significant critical care experience. The two physicians in this or submarine, has to manage a patient with severe ARDS,
scenario are likely aware of the mortality benefit of proning in he or she is unlikely to survive unless rapidly evacuated to a
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ARDS, but this practice is time- and labor-intensive and these higher level of care. While there were two physicians able to
Drowning and Hypothermia on an Amphibious Warship | 75