CHAPTER 21 — Recompression Therapy
Change A 21-21
21-5.5.7
Ancillary Care and Adjunctive Treatments. Drug therapy should be administered
only after consultation with a Diving Medical Officer. Chamber tenders shall be
adequately trained and be capable of administering prescribed treatments. Always
ensure patients are adequately hydrated. Fully conscious patients may be given
fluid by mouth to maintain adequate hydration. One to two liters of water, juice, or
non-carbonated drink, over the course of a Treatment Table 5 or 6, is usually suffi-
cient. Patients with Type II symptoms, or symptoms of arterial gas embolism,
should be considered for IV fluids. Stuporous or unconscious patients should
always be given IV fluids, using large-gauge plastic catheters. If trained personnel
are present, an IV should be started as soon as possible and kept dripping at a rate
of 75 to 100 cc/hour, using isotonic fluids (Lactated Ringer’s Solution, Normal
Saline) until specific instructions regarding the rate and type of fluid administra-
tion are given by qualified medical personnel. Avoid solutions containing only
Dextrose (D5W) as they may contribute to edema as the sugar is metabolized. In
some cases, the bladder may be paralyzed. The victim’s ability to void shall be
assessed as soon as possible. If the patient cannot empty a full bladder, a urinary
catheter shall be inserted as soon as possible by trained personnel. Always inflate
catheter balloons with liquid, not air. Adequate fluid is being given when urine
output is at least 0.5cc/kg/hr. A gauge of proper hydration is a clear colorless
urine.
21-5.5.7.1
Steroids. There is no consensus on the usefulness of adjunctive therapy, other
than IV fluids. The most frequently recommended adjunctive therapy is dexam-
ethasone (Decadron), based on the following reasons:
It decreases tissue swelling (edema)
It decreases tissue inflammation
It decreases leaking of blood vessels
It helps prevent histamine release
General opinion is that spinal cord and brain edema cause many late-appearing
neurologic problems in DCS. Research suggests that dexamethasone is not useful
during treatment of AGE. In this case steroids may be useful but their efficiency
has not been proven. They do not become effective, however, for 4 to 6 hours after
intravenous introduction. Therefore, administer these drugs early in the treatment.
Do not delay recompression while preparing these drugs. For cerebral edema, the
initial recommended dose is 30 mg/kg IV bolus, followed by a constant infusion of
5.4 mg/kg/hr of methylprednisolone. Continue infusion for 23 hours. No benefit
has been documented if steroid treatment was not started within 8 hours of
symptoms.
21-5.5.7.2
Lidocaine. Several studies suggest that Lidocaine used in antiarrhymic doses
(loading dose 1.5 mg/kg drip rate 1 mg/min) may be useful. Its mechanism of
action for treating DCS has been hypothesized as:
Reduction of cerebral metabolic rate
Preservation of cerebral blood flow
Reduction leukocyte adherence to damaged endothelium
