|
Text & Photos by: Bruce Konefe
Just about every dive boat that you will dive
from carries a large oxygen cylinder in case of a
diving emergency.
We were taught all the way bay back
in our open water courses that oxygen is used to
treat an assortment of diving related accidents.
To breathe oxygen at higher partial
pressures gives us an even greater benefit during
treatment. The best way to achieve a higher partial
pressure is to use a hyperbaric chamber. There are a
few different types of hyperbaric chambers but the
two we will be discussing are the mono-place and the
multi-place chambers. Just from the names you can
understand that a mono-place chamber can hold only
one person and that a multi-place can hold more than
one patient at a time. In this article I just want
to cover the advantages and the disadvantages of the
two different types of chambers. I do not want this
to scare you away from getting treated, but to
increase your knowledge of the subject. If you ever
suspect yourself or your dive partner of having
Decompression Illness (DCI), get them to the nearest
hyperbaric chamber whether it is a mono-place or a
multi-place chamber. Let the highly experienced
doctors treat you in the best way they know how.
The larger multi-place chamber is designed more for
the treatment of DCI. A mono-place chamber is better
designed for treatment to heal wounds. Normally
treatments for DCI will take anywhere from 2.5 hours
to almost 5 hours. In the more difficult treatments
the schedule can be extended by more than an hour.
This is one reason why a multi-place is better
suited for DCI treatments in that you do have room
to move around and are not in a confined space and a
tender or doctor can be in there with you in case
you need further help.
Treatments for healing wounds including burns
normally take around 1½ hours. One of the greatest
benefits of multi-place chambers is that many can
treat divers at a higher pressure, some up to a 6
ATA limit; most mono-place chambers have a maximum
depth equivalent of 18 metres. In some very bad
cases greater pressures are needed for treatment.
However, the majority of treatments are done at the
equivalent of 18 metres with the patient on 100% O2,
meaning the patient is at a 2.8 ATA. This treatment
can be carried out in both a mono-place and a
multi-place chamber.
Oxygen toxicity in a multi-place chamber
During the majority of DCI treatments the patient
will be breathing oxygen at 2.8 ATA; this is a lot
higher exposure than the body is used to. Being at
this higher oxygen exposure can affect the central
nervous system and cause pulmonary damage, depending
on the pressure and length of exposure time. These
high exposures can cause a seizure which is one of
the main concerns. A seizure can normally last a
couple of minutes; during which the patient will
loose control of his or her body. During this time a
patient having a seizure can hurt themselves from
loss of control, mainly to the head area. If you are
in a mono-place chamber the chamber needs to be
ventilated and in an emergency an emergency
decompression procedure has to be performed. When a
patient is having a seizure there is a chance the
patient will hold his or her breath which can cause
more complications during the emergency
decompression procedure. One thing that has to be
understood is that in a mono-place chamber the
patient is in there alone without any assistance
from a tender. During all treatments performed in a
multi-place chamber there is an assigned chamber
tender that is in the chamber with the patient to
help and assist them in case a seizure does occur or
if they need any other medical assistance.
Most multi-place chambers have what is called a
Double Lock entrance. A double lock system allows
for a doctor or a further patient to enter while a
treatment is underway. What makes this convenient is
that in case of an emergency a fully qualified
doctor (diving medical officer) can enter a small
separate chamber, which is then pressurised to
equalise with the pressure in the main chamber. Once
the pressure between the two chambers is the same,
the doctor can pass through into the main chamber.
The same system is used for a Med Lock, medical
supplies, water, etc can be passed from the outside
to the tender inside of the chamber.
Upkeep of chambers
Multi-place chambers take up a lot more space inside
a hospital especially when you have a chamber that
can hold 6-12 patients at one time. In case of an
emergency you need to have enough air/O2 supplies to
finish the treatments. Multi-place chambers need to
have much larger storage tanks to hold this air/O2.
Mono-place chambers are much more compact and can be
pushed out of the way when not being used; it is
normally impossible to move a large steel chamber.
The maintenance on the multi-place costs a lot more
money, especially when you consider how much it
costs to maintain the large air compressors, plus
electricity and other facility costs.
Conclusion Whatever the case may be, if you think
there is a possibility that you have DCI call a
DAN-supported dive emergency hotline and get advice
about whether you should get yourself to a chamber
immediately. In the event of DCI, the sooner you
start breathing near-100% oxygen, and the sooner you
get recompressed, the better your chances are of
making a full recovery. DO NOT WAIT!
bruce_konefe@yahoo.com
|
