INTRODUCTION:
The leading causes of sudden death before old age, in people over the age of 44, are ventricular fibrillation from asymptomatic ischaemic heart disease or non-traumatic accidents such as drowning and poisoning. In people under the age of 38, the commonest causes are traumatic, due to accident or violence. In such instances death may be prevented if airway obstruction can be reversed, apnoea or hypoventilation avoided, blood loss prevented or corrected and the person not allowed to be pulseless or hypoxic for more than 2 or 3 minutes. If, however, there is circulatory arrest for more than a few minutes, or if blood loss or severe hypoxia remain uncorrected, irreversible brain damage may result.
Immediate resuscitation is capable of preventing death and brain damage. The techniques required may be used anywhere, with or without equipment, and by anyone, from the lay public to medical specialists, provided they have been appropriately trained.
Resuscitation may be divided into three phases:
1. Basic Life Support using little or no equipment.
2. When equipment and drugs become available Advanced Life Support may start, in which a spontaneous circulation is restored. ;
3. Prolonged Life Support which is usually conducted in an intensive therapy unit and is directed towards salvaging cerebral function; in the comatose patient, maintaining a stable circulation, restoring oxygenation to normal and other aspects of intensive care.
When confronted by an apparently unconscious patient, first establish that they are unconscious by shaking him and shouting at him. Then call for help without leaving the patient. Immediately check that he has a patent airway, and, if not, provide one. If the patient is unconscious but is breathing through a patent airway, then he should be rolled into a stable position on his side with the face pointing slightly downwards. The head should be tilted backwards and the jaw supported to keep the airway patent .
In this position, it will be less likely that the tongue will fall backwards to obstruct the pharynx, and saliva, blood and vomitus will be able to Artificial ventilation and external cardiac massage with one operator only. 15 sternal compressions are alternated with 2 inflations of the lungs. The chest should be compressed at a rate of about 80 per minute; the return of a spontaneous pulse should be checked every 2 minutes or so drain forwards out of the mouth instead of being aspirated into the lungs. If the patient is not breathing then, while keeping the airway patent, he should be put on to his back and artificial ventilation started. Finally, his pulse should be palpated - preferably at the carotid artery in the neck. If no pulse can be felt and the patient is? unconscious, it must be assumed that he is in cardiac arrest. Whiled continuing to provide artificial ventilation, external cardiac massage; should also be given to maintain the patient’s circulation. Where a patient is already in hospital having his ECG monitored when he has cardiac arrest, and it is known that he went into witnessed ventricular fibrillation during the last 30 seconds, then the' treatment of choice would be to first attempt to defibrillate him using 200 joules (J). If this did not succeed, then one should immediately proceed to Basic Life Support with the maintenance of a patent airway and ventilation as well as keeping the patient’s circulation going with external cardiac massage as described below.
THE ABC OF RESUSCITATION
Basic Life Support
A. AIRWAY J
1. Ensure that the patient has a patent airway.
2. Remove fluid and debris from the mouth using fingers and, suction as necessary.
3. Insert a pharyngeal airway if necessary and available.
B. BREATHING
1. Maintain a patent airway.
2. If the patient is breathing roll him on to his side into a stable position with the head tilted back. Maintain a patent airway and check that breathing does not stop. Check his pulse.
3. If the patient is not breathing leave him on his back and;
4. Inflate the patient lungs rapidly 3 to 5 times using one of the; following methods:
(a) Use mouth to mouth or mouth to nose ventilation.
(b) Insert a Brook airway, give mouth to airway ventilation. |
(c) Ventilate the patient using a bag and mask.
5. Look for the rise of the patients chest with each ventilation. If this is not seen there may be
(a) an obstruction in the airway,
(b) a poor seal with the patient’s airways during inflation, or
(c) simply not enough air being blown into the patient.
6. Feel for the carotid pulse.
If the pulse is present, but no spontaneous ventilation, then continue 12 lung inflations per minute.
C. CIRCULATION
1. If the pulse is present and there is obvious external hemorrhage, control bleeding by applying pressure to the bleeding point and elevating it if appropriate.
2. If the pulse is absent, and
3. If there is no spontaneous breathing or gasping, then
4. Transfer the patient to the floor, if he is not already on a hard surface, and start external cardiac massage:
(a) The correct position for placing the hands when giving external cardiac massage,
(b) Compression of the chest with the heel of the hand on the sternum, and the second hand bn it. The heart and major vessels in the chest are compressed between the sternum and the vertebral body,
(c) Without losing contact with the patient’s chest, the pressure on the chest should be released for 50 per cent of each cycle to allow the heart and blood vessels to fill with blood
Artificial ventilation and external cardiac massage with two operators. The first operator compresses the chest at one per second, the second operator inflates the lungs once every fifth compression.
Single operator: Alternate 2 quick lung inflations with 15 sternal compressions . Compress the sternum at a rate of 80/min
Two operators: Alternate 1 lung inflation with 5 sternal compressions . Compress at a rate of 60/min. The lower third of the sternum should be compressed about 5cm (2in) each time.
Resuscitation should be continued until a spontaneous pulse returns.
Advanced Life Support (The restoration of a spontaneous circulation)
D. DRUGS
1. Cardiac compression and ventilation of the lungs should not be interrupted.
2. A central or peripheral intravenous catheter or needle should be inserted if not already in place.
The trachea should be intubated (when possible this should be done by someone appropriately skilled in the procedure). Not only will this make maintenance of the patency of the airway much easier, it will also protect the airway to some extent from contamination by fluid or vomitus, and make artificial ventilation much easier to perform effectively.
4. The following drugs may be used:
(a) adrenaline 0.5-1 mg, repeated every 3-5 minutes as necessary.
(b) sodium bicarbonate ImEquiv/kg body-weight. This is repeated every 10 minutes of arrest time. For adults an 8.4% bicarbonate solution is used (this contains imEquiv/ml); however, this solution is generally too concentrated for small children, for whom a 4.2% solution should be used.
(c) intravenous fluids as required, e.g. blood or plasma.
5. If intravenous access is not established, drugs may be given down the endotracheal tube directly into the patient’s airway, where they work as quickly as when given intravenously. The exception to this is bicarbonate solutions, which must only be given| intravenously.
6. As a last resort, drugs such as adrenaline may be given directly into the heart through the chest wall, though this may damage the heart muscle or cause a pneumothorax.
E. ECG (electrocardiogram)
As soon as possible the ECG of the patient should be monitored: Ventricular fibrillation should be treated by defibrillation, Asystole should be treated with adrenaline and then defibrillation.
Ventricular tachycardias may be treated by defibrillation or verapamil.
Bradycardias may be treated with atropine.
F. FIBRILLATION TREATMENT
If coarse ventricular fibrillation or ventricular tachycardia are seen then clear the area and DC defibrillate the patient. Cardiac massage and ventilation should not be interrupted for more than a few seconds.
1. External defibrillation using 100-400J. Repeat shock as if necessary.
2. Convert fine fibrillation to coarse fibrillation using adrenaline.
3. Lignocaine 1-2mg/kg intravenously as necessary. If a defibrillator is not available, then lignocaine intravenously or via the endotracheal tube may convert to a sinus rhythm.
Stylised ECG patterns:
1. The fixed, prolonged P-R interval of first degree atrioventricular block
2. A gradually increasing P-R interval, followed by a dropped beat, typical, of the Wenckebach type of second degree heart block
3. Fixed 2:1 type of second degree heart block (2 P waves for each QRST complex) it
4. Complete atrioventricular heart block with total dissociation of P waves and QRS complex
5. Atrial fibrillation with irregularly spaced QRS complexes, no visible P waves and a finely irregular baseline between QRS complexes
6. Ventricular tachycardia with wide and rapid QRS complexes
7. Coarse ventricular fibrillation with no normal features visible at all
8. Fine ventricular fibrillation
9. Artifact due to patient movement, with completely irregular, narrow, high voltage complexes overlying normal, regular QRS complexes
External electrical defibrillation.
After connecting the defibrillator to the power supply and switching on, it should be charged to give 200 joules), or roughly 3J/kg body-weight. The electrodes should be well lubricated with conductive jelly, and placed one just below the patient’s right clavicle and the other over the cardiac apex. Clear the immediate area, ensure that no one is touching the patient or the bed* apply firm pressure on to the patient’s chest with the paddles and press the defibrillator button. Wait 5 seconds to confirm the resultant ECG and resume external cardiac massage and artificial ventilation as necessary. The latter should not be interrupted for more than 30 seconds for defibrillation.
Prolonged Life Support (on intensive therapy unit)
GAUGING
1. Gauge the likely outcome of resuscitation.
2. Gauge the cause of the cardio-respiratory arrest and treat it.
H. HUMAN MENTATION
1. Preserve cerebral function by maintaining normal cerebral blood flow and oxygenation.
This may necessitate prolonged mechanical ventilation via a tracheal tube, or even the insertion of a tracheostomy tube in order to facilitate this. The patient may require oxygen to be added to the respiratory gas mixture in carefully controlled amounts, with repeated estimations of the oxygen content of the patient’s blood.
2. Reduce and control intracranial pressure. This may necessitate the insertion of devices through the
patient’s skull to measure intracranial pressure continuously so, that there may be modified accordingly.
Mechanical ventilation is one of the most important ways to reduce and maintain stable the patient’s intracranial pressure. If the intracranial pressure is allowed to rise due to swelling or bleeding, this will reduce the blood flow to the brain and, hence, also reduce the oxygen supply to it. The patient may also be given steroids and diuretics to reduce the swelling.
3. Monitor cerebral function. The electrical activity of the brain may be monitored continuously with a variety of cerebral function monitors (CFMs). More specific information may be obtained with repeated electro-encephalograms (EEGs). |
Repeated neurological examinations by the doctors and careful observation of the patient by all members of staff will provide invaluable information on the degree of neurological damage recovery exhibited by the patient.
I. INTENSIVE CARE
1. Provide intensive therapy.
2. Intensive nursing.
3. Intensive monitoring.
Patients who have undergone cardio-respiratory resuscitation need careful monitoring and care afterwards. They may have a further cardiac or respiratory arrest from the same cause as the original insult or as a result of its consequences. This will necessary intensive monitoring of the patient’s condition at all times provision of immediate skilled resuscitation within seconds. He m% require cardiac, as well as respiratory, support in order to maintain adequate tissue oxygenation. This cardiac support may be pharmacological, using drugs such as dopamine to increase cardiac output or vasodilators such as sodium nitroprusside to reduce the work done by the heart. On the other hand, the support may be mechanical using the aortic balloon pump.
In a similar way, support for the patient who has had a respiratory arrest may be either pharmacological or mechanical. Pharmacological support may be provided with respiratory stimulants such as doxapram or, in the case of narcotic overdoses by the narcotic antagonist naloxone. Mechanical support may be provided with ventilators.
One of the commonest problems encountered in these patients is acute renal failure, but with careful management function may be restored to normal. Patients with renal failure will require careful monitoring of their fluid input and urine output, serum and urinary electrolytes and osmolality. Fluid restriction, diuretics and, possibly, peritoneal or haemodialysis will be required.
summarizes action and management following cardiac arrest.
Flow chart summarizing action and management following cardiac arrest.
THOSE ABOVE ARE COLLECTED FROM SOME BOOKS AND
WEBSITES..
(CASH TEXTBOOK)
THANK YOU,
Comments