(1) Percussion in precordial region was performed within 1 minute after cardiac arrest. From the height of 20 ~ 30cm away from the patient's chest wall, punch the precordial area or the middle sternum 2 ~ 3 times. If you fail, give up. Time cannot be wasted. One punch can generate energy equivalent to 5 ~ 10 joules, which is expected to restore the heartbeat of some patients.
(2) Chest compressions put the patient in a supine position, with the head not higher than the heart level and the lower limbs raised. If chest compressions are performed in bed, a hard plate should be placed on the patient's back, and one hand should be placed in front of and behind his sternum, parallel to the patient's long axis. The palmar root is equivalent to 1/3 and 2/3 below the sternum, and the other palmar root is overlapped on it, and the elbow is straight. Depending on the weight of the operator, the lower end of the sternum should be pressed rhythmically in the direction of the spine, so that it sinks 4 ~ 5 cm, and then quickly relaxed to make the chest bounce. The pressing frequency is 80 ~ 100 times/minute, and each pressing and relaxing time should be continuous without a moment's interruption. Precautions when pressing: ① The pressing position is correct, not too high or too low, not left or right, and never press the xiphoid process under the sternum; ② During direct compression during intermittent relaxation period, the performer's hands will not leave the patient's chest wall to avoid dislocation; ③ Press evenly and rhythmically to avoid sudden and rapid punching. The criteria for judging whether chest compressions are effective are: ① the carotid artery or femoral artery can be touched; ② The systolic blood pressure should be kept above 8kPa(60mmHg); ③ The color of lips and skin turns red; (4) The dilated pupil shrinks again, and the eyelash reflex recovers; ⑤ Restore spontaneous breathing; ⑥ Muscle tension is enhanced.
2) artificial respiration
(1) Mouth-to-mouth artificial respiration When the airway is unobstructed, the operator holds the patient's cheek with one hand and opens his mouth. Hold your nostril with the other hand, take a deep breath, wrap your lips around the patient's lips and blow, each time the air volume is about 800 ~ 1200ml, and then move your mouth away. Passive exhalation is completed by the patient, so it is repeated 16 ~ 20 times per minute. The sign of whether blowing is effective is chest fluctuation; Feel the resistance of lung expansion when blowing; There is gas discharge during passive exhalation. When resuscitated by a single person, the ratio of cardiac compression to ventilation is 5∶ 1
(2) Mouth-nose artificial respiration If the patient's teeth are closed or extracted, the mouth and lips are not tightly sealed, and the distance between the baby's mouth and nose is too close, it is delicious to breathe through the nose. The method is to press the forehead with one hand to make the patient's head lean back, lift the jaw with the other hand to make the patient's mouth and lips close, take a deep breath, the volume is the same as before, and the lips wrap the patient's nostrils to blow.
3. Advanced recovery means further saving lives.
1) further maintain effective ventilation and circulation: tracheal intubation should be used as soon as possible to supply oxygen under pressure, and artificial balloon extrusion or artificial respirator can be connected for mechanical breathing. The time of tracheal intubation should be 72 hours, and the longest time should not exceed 5 days to prevent tracheal softening and collapse during extubation. When using the ventilator, we should pay attention to the management of the ventilator and deal with the problems in time. Humidify the respiratory tract regularly, give 5 ~ 10 ml of normal saline every12h, and deflate the balloon every 4 hours for15min, so as to avoid ulceration or necrosis of the tracheal mucosa caused by long-term compression.
2) Application of cardiac resuscitation drugs
(1) Adrenaline is an α-adrenergic and β-adrenergic nerve receptor agonist, which can accelerate heart rate, contract myocardium and enhance peripheral vascular resistance. When used in cardiac arrest, it is helpful to increase the blood flow of myocardium and brain tissue, turn ventricular fibrillation into coarse fibrillation, and is beneficial to electrical defibrillation. At present, early use and increased dosage are advocated. Common dosage and method: 0.5 ~ 1 mg intravenous injection, and repeated administration every 5 minutes if necessary. If venous access is not established, 1mg can be given through tracheal intubation, or 0.5 ~ 1 mg of adrenaline can be injected subcutaneously, intramuscularly and intracardially.
(2) Lidocaine is a type I antiarrhythmic drug, which is the main drug to treat ventricular arrhythmia. In case of frequent ventricular premature beats, ventricular tachycardia and ventricular fibrillation, lidocaine 50 ~ 100 mg should be injected intravenously immediately. If it fails, it can be repeated every 5 ~ 10 minutes, and the total load should be below 300mg, then 1 ~.
(3) Atropine is an M-type cholinergic receptor blocker, and its main function is to improve sinus rhythm and promote atrioventricular conduction. Generally given 1 ~ 2 mg, 5% ~ 25% glucose 10 ~ 20 ml diluted and injected intravenously. If necessary, repeat administration of 0.5mg every 5 minutes, or intracardiac injection of 0.5 ~ 1 mg. Intravenous atropine occasionally induces ventricular fibrillation and ventricular tachycardia.
(4) As an adrenergic blocker, toluenesulfonyl ammonium bromide can directly enhance contractility and improve atrioventricular conduction. Clinically, it is mainly used for refractory ventricular tachycardia and ventricular fibrillation that lidocaine or cardioversion is ineffective. It is usually given by slow intravenous injection after being diluted with 3 ~ 5 mg/kg and 20 ml of 5% glucose solution. The total load is less than 30mg/kg, and the maintenance capacity is 1 ~ 2 mg/min. (5) Sodium bicarbonate can directly increase the body's alkali reserve and reduce the hydrogen ion concentration in the body. However, if it is used too much, the HCO- induced PCO2 will increase, and at the same time, the oxyhemoglobin curve will shift to the left, which will inhibit the release of oxygen, and CO2 will accumulate in myocardial cells and brain cells, affecting their functional recovery. Therefore, in blood gas analysis, it is only used in the case of cardiac arrest caused by hyperkalemia and severe metabolic acidosis. Intravenous drip is the best common method. The dosage of 5% sodium bicarbonate is 20 ~ 50ml at a time, and the maximum dosage is 100ml at a time.
(6) Calcium preparation is not routinely used for cardiopulmonary resuscitation, but only used for patients with hypocalcemia and calcium antagonist poisoning due to repeated ventricular fibrillation induced by hyperkalemia. Disabled when digitalis poisoning is suspected. 3 ~ 5ml of 5% calcium chloride or 5 ~ 10% calcium gluconate each time, and then add it into glucose solution for slow intravenous injection.
3) Electrical defibrillation and pacing: ECG monitoring should be carried out as soon as possible to understand the nature of cardiac arrest and guide treatment.
(1) electrical defibrillation Once ventricular fibrillation is confirmed by ECG, DC asynchronous defibrillation should be performed immediately. The first electric energy is 250 ~ 300 Joules, which can increase the energy to 360 Joules. If it doesn't work, you can shock again with the same energy in a short time (within 3 minutes). If the ventricular fibrillation wave is small, 0.5 ~ 1 mg epinephrine can be injected intravenously before electric shock. Because 80% of cardiac arrest is ventricular fibrillation, we can perform blind defibrillation without waiting for ECG results.
(2) Electrical pacing leads to cardiac pacing by inserting electrodes subcutaneously and intravenously.
4. After the recovery of heartbeat and breathing, the circulatory function is unstable, the body is still in a state of hypoxia, and the functions of the heart, brain, lungs, kidneys and other organs are low, which requires further treatment. First of all, according to the poisons and drugs that cause cardiac arrest and the metabolic disorder caused by them, antidotes, antagonists and drugs that restore the balance of the internal environment are used to maintain the functions of the heart, lungs and kidneys, prevent and treat brain edema and cerebral hypoxia, maintain the balance of water, electrolyte and acid and alkali, and prevent and treat secondary infections.
1) keep an effective loop.
(1) Application of drugs to improve cardiac function: After the recovery of cardiac beat, its function may be damaged and the myocardial contractility may be inhibited. The following drugs can be considered: ① Dobutamine: combined with sodium nitroprusside, it has synergistic effect. Generally, 250mg is added to 500ml of 5% glucose solution, starting from a small dose, generally 2.5 ~ 20 μ g per minute. ② Sodium nitroprusside: dilate peripheral arteries and veins at the same time, reduce the anterior and posterior load of the heart, thus increasing the cardiac output. Take effect quickly, and stop the drug immediately. Generally, 50 mg is added to 250 ml of 5% glucose solution to prepare a solution of 200 μ g/ml. Intravenous drip at the rate of 0.5 ~ 65438±0.0μg/kg/kg per minute. Use the infusion pump to start with a small dose and adjust it to the required dose. ③ lanatoside C: It can enhance myocardial contractility, increase cardiac output, and reduce left ventricular filling pressure and left ventricular volume. C0.4mg lanatoside C was dissolved in 5% glucose solution and slowly injected intravenously. (4) Nitroglycerin: relax vein vascular smooth muscle, dilate vein, reduce cardiac preload, increase cardiac output and reduce myocardial oxygen consumption; Dosage: intravenous drip at the speed of 10μg/mim, and increase by 5μg/mim every 3 ~ 5 minutes until the required speed, with the maximum dosage of 200μg/mim.
(2) The following drugs should be considered to correct hypotension: ① When the heartbeat has recovered after cardiopulmonary resuscitation, but normal blood pressure cannot be maintained, dopamine and m-hydroxylamine are often used in combination. 20mg of dopamine is usually diluted with 250 ~ 500 ml of 5% glucose solution and given intravenously at a rate of 2 ~ 20 μ g/kg per minute. Start with a small dose and gradually adjust the dropping speed and concentration according to blood pressure. ② m-hydroxylamine is injected intravenously 10 ~ 15 minutes, or 20 ~ 100 mg m-hydroxylamine and 250~500ml of 5% ~ 10% glucose solution are injected intravenously.
(3) arrhythmia is corrected, and arrhythmia often occurs after heartbeat recovery. According to the type of arrhythmia, the following drugs can be selected, such as atropine, lidocaine, pilocarpine C, and toshibromobenzylamine. Usage and dosage are as above. For patients with high atrioventricular block or sinus node failure, artificial pacemakers can be used.
2) Maintain respiratory function (see the later section on acute respiratory failure)
3) correct acidosis: after cardiac arrest, metabolic acidosis is caused by hemodynamic disorder, tissue hypoxia and accumulation of acid metabolites in the body; Respiratory acidosis is the retention of carbon dioxide in the body due to weakened or stopped breathing. In acidosis, the heart is weak in contraction and blood vessels are insensitive to drugs. Correcting acidosis must start from two aspects: respiration and metabolism.
(1) Correct respiratory acidosis, ensure effective blood circulation, quickly establish ventilation and ventilation functions, and pressurize oxygen supply to discharge CO2 trapped in the body as soon as possible.
(2) Correcting metabolic acidosis: While improving respiratory and circulatory functions, alkaline drugs should be used in time. (1) sodium bicarbonate (as mentioned above).
(2) Trimethyl alcohol (THAM): Also known as triple buffer, it can correct acidosis in intracellular and extracellular fluids and reduce sodium and water retention. Generally, 3.64%(0.3mol) solution is used for intravenous injection 150ml each time.
4) Maintain renal function
5) Maintaining the function of the central nervous system: After the heartbeat is restored, it is necessary to carry out treatment to protect brain cells and maintain the function of the central nervous system.
(1) dehydrating agent is suitable for brain edema, and water-electrolyte balance should be paid attention to during dehydration.
(2) Chlorpromazine: 25 ~ 50mg intramuscular injection can be selected to relieve spasticity; Diazepam: 5 ~ 10 mg, intramuscular injection or intravenous injection.
(3) To improve cerebral circulation and metabolism of brain cells, 0.5 ~ 0.75g of choline cytidine diphosphate can be used for intravenous drip in 250ml of glucose solution or intramuscular injection of 0.1~ 0.25g twice a day.
6) Use drugs that promote cell metabolism, such as ATP, cytochrome C, coenzyme A, etc.
7) Application of glucocorticoid: It helps to stabilize cell membrane and restore the function of sodium and potassium pump.
200 ~ 300mg (1) hydrocortisone was added into 500ml 5% glucose solution for intravenous drip.
(2) Dexamethasone 5 ~ 10 mg, intravenously every 6 ~ 8 hours 1 time.
8) Support therapy: provide foods with high protein, high sugar and high vitamins, feed those that cannot be eaten, and feed them by nose. When necessary, input human albumin, plasma or whole blood, etc.
9) Maintaining the balance of water and electrolyte and preventing infection: it is an important condition to ensure the success of recovery, and corresponding treatment should be carried out according to specific conditions.