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DRUGS
IN RESUSCITATION
While
emergency drugs are essential in resuscitation, before giving
a drug, the priorities are always:
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Ventilate |
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Perform
cardiac massage |
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Restore
circulating volume loss |
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Remove
any cause, hazard or noxious agent |
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Make
a diagnosis, if possible. |
There
are no drugs that will make someone breathe. The only treatment
for the non-breathing patient is to inflate the lungs mechanically,
preferably with a resuscitation bag and mask or a tracheal
tube. If the patient is not relaxed and a tube cannot be
passed, a choice arises between:
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Continuing
with the bag and mask until improvement or further deterioration
(with relaxation) occurs or |
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Giving
a relaxant drug, such as suxamethonium 100 mg, in order
to be able to intubate (see pages 14–5 to 14–6). |
If
you cannot decide whether to give a relaxant to intubate
an unstable patient who might deteriorate, think about the
other conditions present and talk to the health care personnel
looking after these complications to find out the next steps
in their management plan.
Ultimately, intubation and oxygenation override all other considerations.
You should, however, bear in mind the side effects of suxamethonium,
such as hyperkalaemia, a possible contribution to cardiac arrest.
A potentially difficult airway (such as after severe facial
trauma or soft tissue swelling) will make suxamethonium very
hazardous: failure to intubate will mean certain death almost
on the end of the needle seconds later.
Epinephrine (adrenaline)
Epinephrine 1/1000. 1 ml contains 1 mg. This is the standard dose for any cardiac
arrest and also where the cause and/or rhythm are unknown. If you have any doubt
that the needle or cannula is in the vein, dilute the 1 ml ampoule in 10 ml saline.
For severe hypotension, provided circulating volume has been restored:
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Dilute
1 mg in 10 ml saline |
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Give
doses of 0.5 ml–1 ml |
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Observe
the response. |
Epinephrine
saves lives in cases of acute collapse.
Epinephrine should be given as close to the heart as possible, such as into the
internal jugular vein, while external cardiac massage is going on. This is to
get the drug to the place where it is going to have an effect: the myocardium.
Intra-cardiac epinephrine is not recommended, even as a final measure when all
else has failed.
Atropine
0.6–1 mg (10–20 mcg/kg). Give atropine before epinephrine if:
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You
see a severe bradycardia |
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You
suspect excessive vagal tone as a cause (unusual) of
asystole. |
Vasoconstrictors
Ephedrine 10–30 mg for spinal hypotension. Other a receptor agonists
such as phenylephrine or methoxamine can be used. Vasoconstrictors are
sometimes used in septic shock, but usually with limited effect.
Calcium chloride
10 mg in 10 ml during a cardiac arrest may be used to promote the effects of
adrenaline and improve myocardial contractility.
Sodium bicarbonate
Give only when there is a proven acid-base problem.
Lidocaine
1–2 mg/kg. Lidocaine has anti-arrhythmic properties. It is not
usually needed in CPR.
Beta blockers
Beta blockers have a role in hypertensive crises. Examples are:
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Atenolol |
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Propranolol |
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Labetolol. |
These
drugs slow the rate and force of contraction of the heart.
They can be used in conjunction with vasodilators such as
hydralazine, nitrates and calcium blockers. This type of
complex therapy is more likely to be used by a physician
in a tertiary hospital.
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