Special Operations Forces Medical Handbook

6-8

Plan:
Treatment: See Treatment Tables at the end of this chapter.
Primary:

1. 100% oxygen immediately. Do not let the patient sit up prior to recompression


2. Hyperbaric oxygen (HBO) recompression therapy as soon as possible.


3. If transportation to HBO chamber is necessary, transport supine, and fly below 1000 ft or pressurize the
   cabin to below 1000 ft. Use fluid, as opposed to air, in bulbs on Foley, ET tube, etc. to reduce risk of
   rupture with pressure changes.


4. Hydrate patient. Fully conscious patients may be given po fluids: two liters of water, juice or non-
   carbonated drink, over the course of a Treatment Table 6, is usually sufficient. Stuporous or unconscious
   patients should always be given IV fluids (normal saline at a rate of 75-125 cc/hour). If the patient is
   dehydrated, give a one-liter bolus of normal saline. Keep fluids running so urine is clear and at least
   30cc per hour. Ringer’s Lactate can be used after patient is producing urine. Catheterize patients
   unable to urinate.


5. Be prepared to immediately treat clinically diagnosed pneumothorax with 14-16-gauge needle (needle
   thoracentesis) and chest tube while at depth or while surfacing (See Procedure: Thoracostomy).
   Alternative: Submarine escape pod may be used for decompression if no chamber is around, 100% Oxygen
   Primitive: In-water recompression (extremely risky; follow “In Water Recompression” instructions in Navy
   Dive Manual Revision 4), 100% Oxygen

Patient Education
General: An AGE stops blood flow to tissues and organs distal to the blockage. By going back down to
pressure, the gas bubbles causing the blockage will shrink to alleviate the AGE. Rapid recompression is
essential to minimize neurological damage.
Activity: Lay supine during travel and recompression to minimize neurological damage.
Diet: Drink fluids to remain hydrated (if able).
Prevention and Hygiene: Avoid diving until cleared by a Diving Medical Officer.
No Improvement/Deterioration: Neurological symptoms can get worse and AGE can lead to death. Recom-
pression as soon as possible is the best treatment to prevent permanent damage. Return daily for 3 days for
assessment of possible residual symptoms.

Follow-up Actions
Return evaluation: Assess possible residual symptoms daily for 3 days and follow the algorithm (Figure 6-1)
from USN Dive Manual. If residual symptoms are present, additional HBO therapy may be indicated (contact
Diving Medical Officer). Physical rehabilitation may be beneficial and neurological follow-up is required.
Evacuation Consultation Criteria: A Diving Medical Officer should be consulted as soon as possible.
Evacuation should be considered as soon as patient is stable.

NOTES: If a limb is paralyzed, a deep vein thrombosis may form, increasing the risk of pulmonary embolism.
Prophylactic low molecular weight heparin (LMWH) may be beneficial if HBO therapy does not alleviate the
paralysis. LMWH is dangerous because it greatly increases the risk of uncontrollable hemorrhage. It must
be used very cautiously.

Dive Medicine: Hypoxia

(Including Shallow Water Blackout)

CPT Jeffrey Morgan, MC, USA

Introduction: Hypoxia is the most common cause of unconsciousness in diving operations. As a diver
depletes the residual gas from his tanks or from his lungs (breath hold diving), the partial pressure of oxygen
in the diver drops insidiously, causing hypoxia and unconsciousness. The increased ambient pressure during
descent and at depth also increases the partial pressure of oxygen and other gases. At depth, the elevated