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Cardiac Arrest: Difference between revisions
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==Basic Life Support (BLS)== | ==Basic Life Support (BLS)== | ||
To increase survival after cardiac arrest it is vital to decrease the time to resuscitation. The training of persons in BLS can increase bystander participation in performing cardiopulmonary resuscitation (CPR). When non-arrest victims inadvertently receive CPR it is extremely rare to inflict serious harm (2% | To increase survival after cardiac arrest it is vital to decrease the time to resuscitation. The training of persons in BLS can increase bystander participation in performing cardiopulmonary resuscitation (CPR). When non-arrest victims inadvertently receive CPR it is extremely rare to inflict serious harm (2% chance of a fracture). Furthermore the risk of disease transmission is extremely low, especially without high-risk activities as intravenous canulation. A straightforward protocol has been created to execute BLS (Figure 1).<cite>Koster2</cite> | ||
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If at any stage the patient is | If at any stage the patient is conscious, has normal ventilation or recovers consciousness a care provider should find out what is wrong with the person and get help if needed. Repeated reassessment is necessary to detected deterioration of the patient’s condition. | ||
====Foreign body airway obstruction==== | ====Foreign body airway obstruction==== | ||
An obstruction of the airway is uncommon, but reversible and adequate recognition can prevent cardiac arrest. Airway obstruction is usually related with eating. In a mild obstruction patients can cough and speak and only frequent reassessment is advised. Patients that have a severe obstruction are unable to speak and have problems breathing and coughing. If a patient is still conscious five back blows can be applied between the shoulder blades whilst the patient leans forward. Otherwise five abdominal thrusts can be applied by clenching a fist and grasping it with the other hand. Place the hands it between the rib-cage and the umbilicus and pull sharply inward and upward whilst standing behind the patients. If the patient loses consciousness start BLS.<cite>Koster2</cite> | |||
====Basic life support in children==== | ====Basic life support in children==== | ||
In general the BLS algorithm is similar | In general the BLS algorithm is similar in children. However, due to the differences in underlying pathology of cardiac arrest and the size of children, small changes must be incorporated. Firstly, as pulmonary causes for cardiac arrest are more frequent, the BLS can be started with 5 initial rescue breaths before starting with the chest compression. The chest compression should compress the chest at least one third of the depth. The chest compression can be performed with one or two hands for a child over 1 year and with 2 finger for an infant under 1 year.<cite>Koster2</cite> | ||
====Automatic external defibrillator (AED)==== | ====Automatic external defibrillator (AED)==== | ||
The | The AED is a complex device that analyses the rhythm of patients and delivers a shock to defibrillate patients. It detect whether a patient has ventricular fibrillation or a different arrhythmia. When it detects a shockable rhythm it advises the user to deliver the shock, all settings are automatically adjusted. It also remembers the course of events so that the tracing can be recovered and analysed after the resuscitation. | ||
When the AED is attached during BLS let the AED assess the rhythm. Do not manipulate the person while the AED | When the AED is attached during BLS let the AED assess the rhythm. Do not manipulate the person while the AED assesses the rhythm to prevent motion artefact disturbing the detection algorithm. Follow the instructions of the AED; this can be either a shock or no shock. After shock or non-shock immediately continue with chest compressions and rescue breaths. Continue the CPR until the AED rechecks the rhythm. Standard AED are usable for children older than 8 years, special paediatric pads and an AED paediatric mode should be used in younger children.<cite>Deakin3</cite> | ||
==Preventing in Hosptial Cardiac Arrest== | ==Preventing in Hosptial Cardiac Arrest== | ||
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====Post-cardiac arrest treatment==== | ====Post-cardiac arrest treatment==== | ||
After cardiac arrest and return of spontaneous circulation the whole body ischemia/reperfusion affects all organ systems. Multiple organ failure, increased risk of infection, neurocognitive dysfunction and myocardial dysfunction are common problems encountered after a cardiac arrest which resembles the problems encountered with sepsis. After resuscitation strict control of oxygenation, cardiac output and glucose metabolism can improve outcome after cardiac arrest. Treatment of the underlying cause of the cardiac resuscitation, for instance a myocardial infarction should be considered. Studies have indicated that | After cardiac arrest and return of spontaneous circulation the whole body ischemia/reperfusion affects all organ systems. Multiple organ failure, increased risk of infection, neurocognitive dysfunction and myocardial dysfunction are common problems encountered after a cardiac arrest which resembles the problems encountered with sepsis. After resuscitation strict control of oxygenation, cardiac output and glucose metabolism can improve outcome after cardiac arrest. Treatment of the underlying cause of the cardiac resuscitation, for instance a myocardial infarction should be considered. Studies have indicated that therapeutic hypothermia (32-34<sup>o</sup>C) during 12-24h after cardiac arrest can increase neurological outcome. This can be achieved by internal infusion or external cooling. Therapeutic hypothermia should be initiated in comatose patients quickly after return of circulation. When cooled the temperature should be maintained without to much fluctuations. Warming of the patient should occur very slowly (0.25<sup>o</sup>C to 0.5<sup>o</sup>C per hour) to prevent rapid plasma electrolyte concentration changes, intravascular volume and metabolic rate changes. | ||
====Prognosis after cardiac arrest==== | ====Prognosis after cardiac arrest==== | ||
Prognosis after cardiac arrest is difficult and cannot be fully predicted. Survival after cardiac arrest is poor, mainly due to neurological damage, and two | Prognosis after cardiac arrest is difficult and cannot be fully predicted. Survival after cardiac arrest is poor, mainly due to neurological damage, and two out of three patients admitted to the ICU following cardiac arrest die from neurological injury. Most prognostic markers have been studied in the era before therapeutic hypothermia. Therefore their value in patients that are actively cooled is incompletely understood. It is not possible to predict outcome reliable within 24 hours after cardiac arrest. Clinical examination of the patient can give information on the prognosis of the patient 24 hours after cardiac arrest. After 72 hours the absence of both pupillary light and corneal reflex predict poor outcome. In patients that are not treated with therapeutic hypothermia absence of vestibulo-ocular reflexes at >24h and a Glasgow coma scale motor score of 2 or less >72 hours after return of spontaneous circulation are possible prognostic markers of a worse outcome. Furthermore myoclonal status is associated with poor outcome, but recovery can occur, and is therefore not useful in determining the prognosis. Electrophysiological studies measuring somatosensory evoked potentials (SSEP) after 24 hours, absence of bilateral N20 cortical response to median nerve stimulation predicts a poor outcome. | ||
==Special circumstances== | ==Special circumstances== | ||
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* <b>Electrolyte disorder:</b> Electrolyte abnormalities are among the most common causes of cardiac arrhythmias. Potassium disorders are commonly seen, especially hyperkalaemia has a high risk of malignant arrhythmias. During cardiac arrest treatment of these abnormalities is no different than in the normal clinical setting, and aggressive treatment of the electrolyte disorder should be initiated. | * <b>Electrolyte disorder:</b> Electrolyte abnormalities are among the most common causes of cardiac arrhythmias. Potassium disorders are commonly seen, especially hyperkalaemia has a high risk of malignant arrhythmias. During cardiac arrest treatment of these abnormalities is no different than in the normal clinical setting, and aggressive treatment of the electrolyte disorder should be initiated. | ||
* <b>Hyperthermia:</b> Exogenous or endogenous hyperthermia can result in heat stress, progressing to heat exhaustion and results in heat stroke. Heat stress can provoke edema, syncope and cramps and is treated with rest, cooling and oral rehydration and salt replacement. Heat exhaustion is a systemic reaction to prolonged heat exposure and is accompanied by headaches, dizziness, nausea, vomiting, tachycardia, hypotension, muscle pain, weakness and cramps. Treatment is similar as in a heat stroke, but active cooling might be required in severe cases with ice packs or cold intravenous fluids. Heat stroke is a systemic inflammatory response with a core temperature above 40,6<sup>o</sup>C. It can lead to varying levels of organ dysfunction accompanied by mental changes. It can occur during high environmental temperatures or during strenuous physical exercise in high environmental temperatures. Rapid cooling of the victim should occur as soon as possible. Patients with heat-stroke usually have electrolyte abnormalities and hypovolaemia. | * <b>Hyperthermia:</b> Exogenous or endogenous hyperthermia can result in heat stress, progressing to heat exhaustion and results in heat stroke. Heat stress can provoke edema, syncope and cramps and is treated with rest, cooling and oral rehydration and salt replacement. Heat exhaustion is a systemic reaction to prolonged heat exposure and is accompanied by headaches, dizziness, nausea, vomiting, tachycardia, hypotension, muscle pain, weakness and cramps. Treatment is similar as in a heat stroke, but active cooling might be required in severe cases with ice packs or cold intravenous fluids. Heat stroke is a systemic inflammatory response with a core temperature above 40,6<sup>o</sup>C. It can lead to varying levels of organ dysfunction accompanied by mental changes. It can occur during high environmental temperatures or during strenuous physical exercise in high environmental temperatures. Rapid cooling of the victim should occur as soon as possible. Patients with heat-stroke usually have electrolyte abnormalities and hypovolaemia. | ||
* <b>Hypothermia:</b> In hypothermia (<35<sup>o</sup>C) it is difficult to detect signs of life. Therefore resuscitation should proceed according to standard protocols until the patient has reached normothermia. Second to resuscitation, warming of the body temperature by passive or active external and internal methods should be started. Examples of passive rewarming are drying and insulation of the body, whilst examples of active rewarming are infusion of warmed intravenous fluids or forced air rewarming. As a result of rewarming vasodilatation occurs and fluid administration may be required.Resuscitation during hypothermia is difficult, the thorax is stiff and the heart is less responsive to medication and defibrillation. Furthermore drug metabolism is slowed, resulting in increased plasma levels of medication. Medication should be administered at double intervals in patients <35<sup>o</sup>C and withheld in patient <30<sup>o</sup>C. Rhythm disturbances usually seen at rewarming after hypothermia are bradycardia, atrial fibrillation | * <b>Hypothermia:</b> In hypothermia (<35<sup>o</sup>C) it is difficult to detect signs of life. Therefore resuscitation should proceed according to standard protocols until the patient has reached normothermia. Second to resuscitation, warming of the body temperature by passive or active external and internal methods should be started. Examples of passive rewarming are drying and insulation of the body, whilst examples of active rewarming are infusion of warmed intravenous fluids or forced air rewarming. As a result of rewarming vasodilatation occurs and fluid administration may be required.Resuscitation during hypothermia is difficult, the thorax is stiff and the heart is less responsive to medication and defibrillation. Furthermore drug metabolism is slowed, resulting in increased plasma levels of medication. Medication should be administered at double intervals in patients <35<sup>o</sup>C and withheld in patient <30<sup>o</sup>C. Rhythm disturbances usually seen at rewarming after hypothermia are bradycardia, atrial fibrillation, VF and asystole. Bradycardia and atrial fibrillation revert to normal sinus rhythm as the core body temperature increases. | ||
* <b>Poisoning:</b> Accidental poisoning in children or by therapeutic or recreational drugs in adults are the main causes of poisoning, however rarely causes cardiac arrest. It is important to identify the poison to start antidote treatment or decontamination. During the BLS and ALS care should be taken when performing mount-to-mouth ventilation in the presence of certain chemical types of poisoning. Respiratory arrest and airway depression is more common after poisoning. Early intubation can prevent cardiac arrest and pulmonary aspiration. When confronted with a poisoning in an ALS setting, temperature should be monitored as hypo- or hyperthermia my occur after drug overdose. Furthermore, due to the slow metabolization or excretion of certain poisons the resuscitation can continue for a long period. | * <b>Poisoning:</b> Accidental poisoning in children or by therapeutic or recreational drugs in adults are the main causes of poisoning, however rarely causes cardiac arrest. It is important to identify the poison to start antidote treatment or decontamination. During the BLS and ALS care should be taken when performing mount-to-mouth ventilation in the presence of certain chemical types of poisoning. Respiratory arrest and airway depression is more common after poisoning. Early intubation can prevent cardiac arrest and pulmonary aspiration. When confronted with a poisoning in an ALS setting, temperature should be monitored as hypo- or hyperthermia my occur after drug overdose. Furthermore, due to the slow metabolization or excretion of certain poisons the resuscitation can continue for a long period. | ||
* <b>Pregnancy:</b> If a cardiac arrest occurs during pregnancy the safety of the fetus should always be considered. Due to the growth of the uterus compression of the inferior vena cava can occur and as a result venous return and cardiac output is compromised. During CPR displace the uterus to the left or apply a left lateral tilt of the surface the patient is lying upon to minimize compression from the uterus. Furthermore the increased abdominal pressure can increase the risk of pulmonary aspiration and can hamper proper ventilation; therefore early intubation can lower risks and ease cardiopulmonary resuscitation. During ALS normal defibrillator shock energies can be used. An emergency hysterotomy or cesarean section needs to be considered, if gestational age is after 20 weeks. After 20 weeks the size of the uterus is large enough to compromise cardiac output, however fetal viability begins at approximately 24-25 weeks. | * <b>Pregnancy:</b> If a cardiac arrest occurs during pregnancy the safety of the fetus should always be considered. Due to the growth of the uterus compression of the inferior vena cava can occur and as a result venous return and cardiac output is compromised. During CPR displace the uterus to the left or apply a left lateral tilt of the surface the patient is lying upon to minimize compression from the uterus. Furthermore the increased abdominal pressure can increase the risk of pulmonary aspiration and can hamper proper ventilation; therefore early intubation can lower risks and ease cardiopulmonary resuscitation. During ALS normal defibrillator shock energies can be used. An emergency hysterotomy or cesarean section needs to be considered, if gestational age is after 20 weeks. After 20 weeks the size of the uterus is large enough to compromise cardiac output, however fetal viability begins at approximately 24-25 weeks. | ||