Post cardiac Arrest Care

 

Ramya K.R.*

Assistant Professor, Baby Memorial College of Nursing, Kozhikose, Kerala

 

ABSTRACT:

Resumption of spontaneous circulation (ROSC) after prolonged, complete, whole-body ischemia creates a pathophysiological state following successful cardiopulmonary resuscitation. The components of post cardiac arrest syndrome comprise post cardiac arrest brain injury, myocardial dysfunction, systemic ischemia/reperfusion response and persistent precipitating pathology. So a comprehensive, structured, multidisciplinary system of care should be implemented in a consistent manner for the treatment among eligible post– cardiac arrest patients. Management of post cardiac arrest care include initial stabilization, general and specific intensive care and monitoring, hemodynamic optimization, circulatory and respiratory support, urgent angioplasty and percutaneous coronary intervention, optimizing neurological recovery include therapeutic hypothermia, sedation and neuromuscular support, seizure control, glycemic control, and neurological, physical and cardiac rehabilitation restore normal functioning for survivors.

 

INTRODUCTION:

The second step in the care of resuscitation-the treatment of the post resuscitation disease.                V A Negovsky

 

The morbidity and mortality associated with cardiac arrest still remain significant in India despite recent advances in resuscitation techniques. Most deaths occur during the first 24 hours after cardiac arrest.

 

Neurological outcomes can often be poor, but there is increasing evidence that interventions in the post arrest period can impact overall outcome. Organized post– cardiac arrest care bundled as an integrated system that focus on optimizing hemodynamic, neurologic, & metabolic function may improve survival to hospital discharge among victims who achieve ROSC (Return Of Spontaneous Circulation)following cardiac arrest. Although it is not yet possible to determine the individual effect of many of these therapies, their deployment may well improve outcomes.

 

Definition:

The complex pathophysiological processes that occur following whole body ischemia during cardiac arrest and the subsequent reperfusion response following successful resuscitation have been termed post cardiac arrest syndrome.

 

Objectives of Post– Cardiac Arrest Care

·        Control body temperature to optimize survival and neurological recovery

·        Identify and treat acute coronary syndromes (ACS)

·        Optimize mechanical ventilation to minimize lung injury

·        Reduce the risk of multiorgan injury and support organ function if required

·        Objectively assess prognosis for recovery

·        Assist survivors with rehabilitation services when required

 

Pathophysiology:

The unique features of post– cardiac arrest pathophysiology are often superimposed on the disease or injury that caused the cardiac arrest, underlying comorbidities, prolonged whole-body ischemia initially causes global tissue and organ injury, additional damage occurs during and after reperfusion.

Table1: Components of post cardiac arrest syndrome

Syndrome	Pathophysiology	Clinical Manifestations	Potential Treatments
Post– cardiac arrest brain injury Fever,hyperglycemia, seizures, too much or too little oxygen delivered during initial treatment can affect severity can affect outcome.	Impaired cerebrovascular autoregulation Cerebral edema. Postischemic neurodegeneration	Coma, Seizures, Myoclonus, Cognitive dysfunction, Persistent vegetative state, Secondary Parkinsonism, Cortical & Spinal stroke, Brain death	Therapeutic hypothermia Early hemodynamic optimization Airway protection and Mechanical ventilation Seizure control Controlled reoxygenation Supportive care
Post–cardiac arrest myocardial dysfunction Transient and can resolve to normal by 72 hours after arrest.	Global hypokinesis, ACS	Reduced cardiac output Hypotension Dysrhythmias Cardiovascular collapse	Treatment of underlying heart disease Early revascularization of AMI Early hemodynamic optimization Intravenous fluid Inotropes Mechanical circulatory assistances
Systemic ischemia/reperfusion response	Systemic inflammatory response syndrome Impaired vasoregulation Increased coagulation Adrenal suppression Impaired tissue oxygen delivery and utilization Impaired resistance to infection	Ongoing tissue hypoxia/ischemia Hypotension Cardiovascular collapse, fever Hyperglycemia Multiorgan failure Infection.	Early hemodynamic optimization Intravenous fluid Vasopressors High-volume hemofiltration Temperature control Glucose control. Antibiotics for documented infection
Persistent precipitating pathology	Cardiovascular disease (ACS, cardiomyopathy) Pulmonary disease (COPD, asthma), CVA, Thromboembolic disease (PE) Toxicological (overdose, poisoning) Infection (sepsis, pneumonia) Hypovolemia hemorrhage, dehydration.	Specific to cause but complicated by concomitant PCAS	Disease-specific interventions guided by patient condition and concomitant PCAS

 

Eligibility Criteria for Post-Cardiac Arrest Care

·        Post-cardiac arrest, defined as a period of absence of pulses requiring chest compressions, regardless of location or presenting rhythm followed by ROSC.

·        Not DNR or DNI status prior to Cardiac Arrest.

·        Pre-arrest cognitive status not severely impaired.

 

Initial Data Gathering (After Stabilization)

1.History:

Review eligibility, contraindications, advance directives and overall prognosis

Discuss issues with health care proxy, if available

2. Physical: Baseline Neurological Evaluation

Exclude other causes of coma (mass lesions, metabolic coma, seizures etc)

Document Glasgow Motor Score and Glasgow Coma Score

3. Initial laboratories

ABG

CBC / PT / PTT/INR, Fibrinogen

Electrolyte levels

Lactate/CPK-MB/CK/Troponin

Cortisol level

Urinanalysis

Blood Cultures, Urine Culture, and Sputum Culture (if appropriate)

Toxicology screen if appropriate

Beta Hcg on all women of child-bearing age

4. Serial laboratories:

Lactate, Repeat CPK-MB/CK/Troponin,CBC / PT / PTT/INR, P7 / Electrolytes, ABG

5. CXR

6. Head CT to rule out intracranial hemorrhage if necessary

7. Others

Cardiac catheterization is indicated, hypothermia should not be delayed.

Echocardiogram to rule out regional wall motion abnormality and severe contractile dysfunction.

Maternal if +Hcg (while initiating hypothermia) in case of child bearing age.

Neurology/ EEG.

8. Establish Appropriate Monitoring Immediately

Cardiovascular:

a.       ECG continuously to rule out arrhythmias/ACS.

b.      Arterial-line for continuous arterial blood pressure monitoring (essential prior to initiating hypothermia).

c.       Intake and output

d.      CVP & Scv02 

e.       Echocardiogram

 

Pulmonary:

Continuous SaO₂ probe, frequent ABGs (use temperature correction), CXR

Temperature: Foley/esophageal with temperature probe.

Neurologic:

a.       Continuous EEG monitoring 

b.      Neurological checks q 2 hrs

Therapeutic Strategies

Evaluate the patient’s condition and care plan must be prioritized and executed in the proper order to optimize the patient’s outcome and help prevent premature withdrawal of care with timely execution. Treatment must focus on reversing the pathophysiological manifestations of the post– cardiac arrest syndrome.

 

General Measures:

The survivor should be admitted to the Intensive Care Unit (ICU) with treatment and monitoring for General intensive care monitoring, more advanced hemodynamic monitoring, and cerebral monitoring. General intensive care monitoring is the minimum requirement; additional monitoring should be added depending on the status of the patient and local resources and experience.

 

Early Hemodynamic Optimization:

Focuses on optimization of preload, arterial oxygen content, afterload, contractility, and systemic oxygen utilization with the help of intravenous fluids, inotropes, vasopressors, and blood transfusion. Goals are MAP of 65 to 100 mm Hg (taking into consideration the patient’s normal blood pressure, cause of arrest, and severity of any myocardial dysfunction), central venous pressure of 8 to 12 mm Hg, ScvO2 70%, urine output 1 ml/kg/hr. The benefits of early goal-directed therapy include modulation of inflammation, reduction of organ dysfunction, and reduction of healthcare resource consumption.

 

Oxygenation :

Avoid unnecessary arterial hyperoxia, especially during the initial post-cardiac arrest period since hyperoxia during the early stages of reperfusion harms postischaemic neurons by causing excessive oxidative stress. This can be achieved by adjusting the FIO2 to produce an arterial oxygen saturation of 94—96%.

 

Ventilation:

Ventilation should be adjusted (PETCO2 35–40 mm Hg Tidal Volume 6–8 mL/kg) to achieve normocarbia and should be monitored by regular measurement of arterial blood gas values.

 

Circulatory Support:

Hemodynamic instability is common after cardiac arrest and manifests as dysrhythmias, hypotension, and low cardiac index. Dysrhythmias can be treated by maintenance of normal electrolyte concentrations and use of standard drug and electrical therapies. The first-line intervention for hypotension is to optimize right-heart filling pressures by use of intravenous fluids. Inotropes and vasopressors should be considered if hemodynamic goals are not achieved despite optimized preload. The choice of inotrope or vasopressor can be guided by blood pressure, heart rate, echocardiographic estimates of myocardial dysfunction, and surrogate measures of tissue oxygen delivery such as ScvO2, lactate clearance, and urine output. Therapy can be further guided by cardiac index and systemic vascular resistance. Pulmonary artery catheter, mechanical circulatory assistances. intra-aortic balloon pump percutaneous cardiopulmonary bypass, extracorporeal membrane oxygenation (ECMO), or transthoracic ventricular assist devices can also be considered.

 

Management of ACS

·        Coronary angiography and percutaneous coronary intervention (PCI – formerly called angioplasty): especially for survivors with acute myocardial infarction (heart attack) and coronary artery disease or any patient suspected of having Acute Coronary Syndrome.

·        Thrombolysis, if no facilities for PCI: in patients with certain types of heart attacks.

 

Therapeutic Hypothermia:

Cooling should be initiated as soon as possible in unconscious adult patients with spontaneous circulation after cardiac arrest to 32°C to 34°C for at least 12 to 24 hours. Therapeutic hypothermia can be divided into 3 phases: induction, maintenance, and rewarming. Induction can be instituted easily and inexpensively with intravenous ice-cold fluids (30 mL/kg of saline 0.9% or Ringer’s lactate) or traditional ice packs placed on the groin and armpits and around the neck and head. Initial cooling is facilitated by concomitant neuromuscular blockade with sedation to prevent shivering. In the maintenance phase, significant temperature fluctuations can be avoided by effective temperature monitoring, external (cooling blankets or pads with water-filled circulating systems) or internal cooling devices (devices inserted into a femoral or subclavian vein).Less sophisticated methods, such as cold wet blankets placed on the torso and around the extremities, or ice packs combined with ice-cold fluids, can also be effective. Slow rewarming is recommended (0.25°C to 0.5°C/h), although the optimum rate for rewarming has not been defined clinically. Care should be taken during the cooling and rewarming phases because metabolic rate, plasma electrolyte concentrations, and haemodynamic conditions may change rapidly. If therapeutic hypothermia is not undertaken, pyrexia during the first 72 hours after cardiac arrest should be treated aggressively with antipyretics or active cooling. Observe for complications like Shivering, increases systemic vascular resistance, which reduces cardiac output, diuresis, dysrhythmias, impaired coagulation and increased bleeding, pneumonia.

 

Sedation and Neuromuscular Blockade:

Adequate sedation will reduce oxygen consumption; prevent shivering which will help to achieve target temperature earlier. Closely monitor for sedation and neurological signs, such as seizures & EEG if necessary.

 

Seizure Control and Prevention:

Treat seizures promptly and effectively with benzodiazepines, phenytoin, sodium valproate, propofol, or a barbiturate. Clonazepam is the drug of choice for the treatment of myoclonus.

 

Glucose Control maintain:

Blood glucose in target range with frequent monitoring & insulin especially when insulin is started and during cooling and rewarming periods.

 

Infection:

Post– cardiac arrest patients are at particularly high risk of developing pneumonia within the first 48 hours of intubation. Rehabilitation to restore normal functioning: Neurological, physical and cardiac rehabilitation for survivors.

 

CONCLUSION:

The best hospital care for patients with ROSC after cardiac arrest is not completely known, but there is increasing interest in identifying and optimizing practices that are likely to improve outcomes. The goal of immediate post– cardiac arrest care is to optimize systemic perfusion, restore metabolic homeostasis, and support organ system function to increase the likelihood of intact neurological survival. The comprehensive treatment of diverse problems after cardiac arrest involves different groups of healthcare providers in multiple locations. Many of the interventions applied in the post resuscitation period do not require expensive equipment. For this reason, it is important to admit patients to appropriate critical-care units with a prospective plan of care to anticipate, monitor, and treat each of these diverse problems. It is also important to appreciate the relative strengths and weaknesses of different tools for estimating the prognosis of patients after cardiac arrest.

 

REFERENCES:

1.       Negovsky VA. The second step in resuscitation: the treatment of the “post-resuscitation disease.” Resuscitation. 1972;1:1–7.

2.       Oddo M, Schaller MD, Feihl F, Ribordy V, Liaudet L. From evidence to clinical practice: effective implementation of therapeutic hypothermia to improve patient outcome after cardiac arrest. Crit Care Med. 2006;34: 1865–1873.

3.       Sunde K, Pytte M, Jacobsen D, Mangschau A, Jensen LP, Smedsrud C, Draegni T, Steen PA. Implementation of a standardised treatment protocol for post resuscitation care after out-of-hospital cardiac arrest. Resuscitation. 2007;73:29 –39.

4.       Robert W. Neumar et al. Post Cardiac Arrest Syndrome. Epidemiology, Pathophysiology, Treatment, and Prognostication A Consensus Statement From the International Liaison Committee on Resuscitation American Heart Association Emergency Cardiovascular Care Committee; the  Council on Cardiovascular Surgery and Anesthesia; the Council on Cardiopulmonary, Perioperative, and Critical Care; the Council on Clinical Cardiology; and the Stroke Council. 2008;11: 23-28

 

 

Received on 23.09.2013           Modified on 30.11.2013

Accepted on 24.12.2013           © A&V Publication all right reserved