Cardiac arrest is a condition in which the heart fails to produce an output. It’s also known as sudden cardiac arrest.
The heartbeat is controlled by electrical impulses. When these impulses change the pattern of functionality, the heartbeat becomes unstable.
The Institute of Medicine however reports that more than half a million people experience cardiac arrest in the United States every year.
It is almost immediately followed by respiratory arrest. The clinical presentation is a combination of physiological functions in a patient whose such function has been compromised by disease or trauma.
Cardiopulmonary resuscitation, therefore, is the establishment of effective cardiac and pulmonary functions in a patient who has suffered cardiac arrest until treatment is provided.
Common Causes Of Cardiac Arrest
- Severe hypoxia: When your body tissues are starved of oxygen. Its symptoms include confusion, restlessness, difficulty breathing, rapid heart rate, and bluish skin. It’s important to note that hypoxia is different from hypoxemia. The former is low levels of oxygen in the body tissues while the latter is low levels of oxygen in the blood.
- Prolonged hypercapnia: This occurs when there is a build-up of carbon dioxide in the bloodstream. Symptoms include anxiety, shortness of breath, headache, dizziness, etc.
- Inherent myocardial diseases like myocardial infarction also known as a heart attacks. Symptoms include chest pain, shortness of breath, dizziness, sweating, etc.
- Electrolyte imbalance as in hyperkalemia
- Hypotension as in hemorrhage
- Electric shock
Clinical Features Of Cardiac Arrest
- Loss of consciousness
- Cold and clammy extremities
- Absence of respiration
- Absence of pulsation in major peripheral arteries
- Fixed and dilated pupil
The ABC of cardiopulmonary resuscitation has to do with Airways, Breathing, and Circulation.
Airway: As soon as a cardiac arrest has been diagnosed, a patient airway is immediately established. The airway is a passage between the lip and the nostrils on the one hand and the alveoli of the lung on the other.
It’s through the airway that oxygen gets to the alveoli of the lung for tissue metabolism and carbon dioxide is expelled from the lung to the outside. Poor alveoli ventilation causes carbon dioxide retention. The airway is obstructed due to the following:
- The tongue falls back against the posterior laryngeal wall due to relaxation of the jaw.
- Secretion of saliva and regurgitation of vomits.
- Blood in the airway in the case of accidents.
- Foreign body in the carina of trachea and bronchi
- Laryngeal packs forgot by doctors or anesthetists.
It has been observed that a normal person cannot withstand more than three to four minutes of anoxia, otherwise, cardiac arrest supervenes. Proper positioning of the patient is vital. The neck is flexed, the head tilted, and the jaw pushed forward. The airway is then cleared of any foreign debris like vomitus or blood either manually or with a sucker. Nasopharyngeal or more commonly oropharyngeal airway such as Brook’s airway is inserted to make for a patient airway.
Breathing: The next thing to do after securing a patent airway is to ensure adequate pulmonary ventilation and oxygenation. The lung is rapidly inflated three to four times by using either expired air, fresh air enriched in oxygen, or a hundred percent oxygen. It is much easier to give and comes more in handy. It consists of the following:
- Mouth to mouth
- Mouth to nose
- Mouth to Brook’s airway
In the mouth-to-mouth, the operator takes a deep breath and then puts his lip tightly around the lip of the patient. Then pinching the patient’s nostril to prevent air leakage through the nare, he blows rapidly into the patient’s mouth. This inflates the lung. He then removes his lip from the patient’s lip to allow for expiration which is a passive process.
In the mouth-to-nose, the operator’s lip is fixed tightly around the nostril of the patient. The patient’s mouth is then closed while air is blown into the nostril. The operator lifts his mouth from the patient’s nostril to allow for expiration.
The mouth of Brook’s airway is similar to the mouth-to-mouth method, except that the operator puts his lip tightly around the distal opening of Brook’s airway.
Whichever of the three methods, after the initial rapid inflation of the lung, should be done at the rate of twelve to fifteen times per minute.
Circulation: Once ventilation has been achieved the next stage is to establish artificial circulation. This is done by external cardiac compression.
Here, the heart is compressed between the sternum and vertebral column. A firm board is used or the patient is put on the floor because a hard surface is required.
The operator stands vertically above the patient who must be 1ying supine. The heel of one hand is placed over the lower third of the patient’s sternum without touching the ribs. The heel of the other hand is placed above the first hand. In infants, only one hand is used while the thumb is used in neonates.
One lung inflation is accompanied by five sternal compressions if two operators are involved with one performing the sternal compression and the other the artificial ventilation like the mouth-to-mouth. However, when it is only one operator performing both functions, then fifteen sternal compressions should be alternated with two lung inflation.
This exercise calls for great care from the operator to avoid such complications as rib fracture and pneumothorax.