What laboratory tests should be checked after a cardiac arrest?

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From the Guidelines

After a cardiac arrest, it is crucial to check arterial blood gases, serum lactate, blood glucose, electrolytes, CBC, and general blood sampling to assess the patient's condition and guide further management. These laboratory tests are essential for identifying the underlying cause of the arrest, assessing end-organ damage, and guiding resuscitation efforts 1. The American Heart Association recommends monitoring options such as arterial catheter, oxygen saturation by pulse oximetry, continuous ECG, CVP, Scvo2, temperature, urine output, and chest radiograph 1. Key laboratory tests to be checked include:

  • Arterial blood gases to assess oxygenation, ventilation, and acid-base status
  • Serum lactate to reflect tissue perfusion and guide resuscitation adequacy
  • Blood glucose to identify any abnormalities that may have contributed to the arrest
  • Electrolytes, particularly potassium, magnesium, and calcium, to identify any imbalances that may trigger arrhythmias
  • CBC to assess for any underlying infections or bleeding disorders
  • General blood sampling to guide further management and identify any underlying conditions that may have contributed to the arrest. Additionally, EEG should be considered for early seizure detection and treatment, and CT/MRI may be useful in certain cases 1. It is also important to note that emergent cardiac catheterization with PCI may be helpful in all arrests of presumed cardiac origin independent of ECG findings after IHCA, and all IHCA patients with ROSC after arrest with ST-segment–elevation myocardial infarction or new left bundle-branch block should undergo emergent angiography and, when indicated, PCI 1.

From the Research

Laboratory Tests After Cardiac Arrest

The following laboratory tests are recommended after a cardiac arrest:

  • Complete blood count (CBC) to assess for potential cardiovascular and metabolic diseases 2
  • Basic metabolic profile to evaluate the patient's electrolyte and acid-base status
  • Liver function tests to assess for potential liver injury
  • Troponin to evaluate for cardiac damage
  • Brain natriuretic peptide (BNP) to assess for heart failure, although it may not significantly change treatment or outcomes 3
  • Electrocardiogram (ECG) to evaluate the patient's cardiac rhythm and potential underlying causes of the cardiac arrest
  • Chest radiograph to assess for potential pulmonary complications, although findings may not be definitive 3

Additional Tests

Other tests that may be useful in the evaluation of a patient after cardiac arrest include:

  • Point-of-care ultrasound to assess for B-lines, cardiac function, and inferior vena cava size 3
  • Coronary evaluation to assess for potential acute coronary syndrome, as early revascularization may improve patient outcomes 4
  • Hemodynamic monitoring to evaluate the patient's cardiovascular status and guide management 5, 4

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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