*** Mammalian Dive Reflex & Rescue vs. Recovery Time ***

Thu Jan  9 11:03:24 1997
Message : #1697502260
From: Thomas C. Gilbert
Address : gilbertt@erols.com
Group   : Usenet.misc.emerg-services
Subject : Re: Rescue vs. Recovery in Water Related Emergencies
Org.  : Erol's Internet Services

Chris Bonin wrote:
>
>Curious about anyone who works with water rescue, ocean in particular,
>who have protocols on when a rescue of a patient (ie resuscitation
>efforts will be attempted) becomes a recovery of a body (no resusitation
>attempt). Preferably looking for these protocols on a BLS (EMT-A)
>level.
>
>On a related note, doe sanyone know at what water temperature does the
>mammalian diving reflex kick in?
>
>Some discussion locally on this issue with my organization and I was
>wondering if anyone has investigated this issue and established any
>protocols.
>
>Please post or email replies. Thanks for any feedback!
>
>Chris Bonin, MICP
>cbonin@mitre.org


Baltimore County (Maryland) Fire Department has/had (I haven't looked it
up recently) an SOP indicating the distinction between a water "rescue"
to a water "recovery" is 60 minutes downtime.
Suspect part of that logic is based on the "golden hour" concept and
part may be due to documented cases of successful cold water recoveries
of children upwards of 48 minutes (mammalian diving reflex).

Regarding the diving reflex, Brady's "Prehospital Emergency Care" book
(5th ed., p.443) indicates "...the mammalian diving reflex can be
triggered in water at or below 68 degrees Fahrenheit..."; "...patients
submerged in cold water 30 minutes or longer in cardiac arrest have been
resuscitated."
I seem to recall from past training that the probability that the reflex
will trigger increases when the patient is younger (up to 4 yrs of age?)
and the water is colder.

Hope this helps,
Tom Gilbert, EMT-B,CRT

Virginia Beach, VA

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