d. Severe brady dysrhythmia--abnormally slow heartbeat with atrial and
ventricular beats less than 60 beats per minute.
3-10. COMPONENTS OF THE DEFIBRILLATOR (LIFEPAK 5)
The defibrillator (Lifepack 5) is made up of these parts:
a. The electrocardiography monitor module (module and recorder).
b. A direct current (DC) defibrillator module with synchronizer. This piece of
equipment has a charge time of 400 joules in 12.5 seconds and can deliver an electrical
charge of 20, 30, 50, 100, 200 or 360 joules.
c. Patient cables.
d. A battery pack charger to recharge two batteries in 4 1/2 hours.
e. A nickel cadmium battery (the power source) which provides a minimum of
twelve 360-joule discharges and 30 minutes of recorder use.
Section III. MAJOR MANAGEMENT TECHNIQUES OF CARDIAC ARREST
3-11. MONITORED CARDIAC ARREST
Monitored cardiac arrest is cardiac arrest (the cessation of heartbeats) that
occurs when an electrocardiogram (EKG or ECG) is monitoring the casualty. Someone
checking the monitor sees that the rhythm of the casualty's heart has changed to
ventricular fibrillation. Ventricular fibrillation is a serious type of electrical failure in the
heart. A ventricle receives extremely rapid, uncoordinated electrical signals that keep
the heart from relaxing fully. When this happens in a ventricle, the affected part of the
heart is unable to pump blood. An electric shock, if given in time, may cause the heart
to beat again in normal rhythm. Follow this procedure to treat monitored cardiac arrest:
a. Verify That There Is No Pulse. Physically check for carotid pulse. Check
the electrocardiogram equipment quickly to make sure that the problem is not just
interference on the monitor due to cable or patient movement. If there is no pulse, do
the next step.
b. Perform Precardial Thump. Using the fleshy part of your closed fist, deliver
a thump eight to twelve inches above the sternum. This thump decreases the
unreliability of the heart muscle and makes it less likely that the heart will start
fibrillating. If this maneuver results in sinus rhythm (normal heart rhythm) with a pulse,
proceed with lidocaine therapy. The dosage of lidocaine depends on the patient's
condition. Usually, the dosage is I mg/kg with additional bolus injection of 0.5 mg/kg
every 2 to 10 minutes, if needed, to a total dose of 3 mg/kg. The maintenance dosage
is 2 to 4 mg.