Cardiac Arrest in a Patient With Pulseless Electrical Activity

Case Study

A rapid response event was initiated by the bedside nurse for a patient with sudden unresponsiveness. On prompt arrival of the rapid response team, it was noted that the patient was a 69-year-old male with a known history of type 2 diabetes, hypertension, COPD (on 4 L/min of oxygen at home), and tobacco abuse disorder, who was admitted with ST-elevation myocardial infarction and was two days post-coronary artery bypass grafting. Upon arrival, the bedside nurse was already performing cardiopulmonary resuscitation (CPR), and the attached cardiac monitor showed pulseless electrical activity (PEA).

Vital Signs

Temperature: 95.7 °F, axillary
Blood Pressure: 80/40 mmHg while CPR being performed
Pulse: could not be palpated
Respiratory Rate: Ambu-bagged at ten breaths per min
Pulse Oximetry: 88% on 100% oxygen with Ambu-bag

Focused Physical Exam

A limited exam was done in the setting of cardiac arrest. It showed a pale, elderly appearing male undergoing chest compressions and bag-valve ventilation. No spontaneous activity was present, and the patient was pulseless. No other examination was performed during CPR.

Interventions

The patient was intubated emergently to secure the airway. A total of two rounds of CPR were performed, and a total of two ampules of 1 mg (1:10,000) epinephrine were administered. A sine wave pattern was seen on the cardiac monitor during CPR ( Fig. 14.1 ). Return of spontaneous circulation (ROSC) was achieved after 5 min, and normal sinus rhythm was restored. Examination after the achievement of ROSC showed that the patient was responding appropriately to painful stimuli. A stat electrocardiogram (EKG) was obtained and showed peaked T waves in the precordial leads ( Fig. 14.2 ). Stat point-of-care (POC) electrolytes were obtained, which showed hyperkalemia with a potassium level of 7.2 mmol/L. Intravenous (IV) calcium gluconate, IV insulin and dextrose, albuterol nebulization, and 40 mg IV Lasix were administered. A stat basic metabolic panel was obtained and confirmed the POC electrolyte derangements. Serum magnesium and troponin levels were unremarkable. The glucose level was normal. He was transferred to the intensive care unit for further monitoring.

Final Diagnosis

PEA secondary to hyperkalemia.

Pulseless Electrical Activity

Definition and Diagnosis

PEA is the presence of an organized electrocardiographic rhythm without any myocardial contractility to produce a palpable pulse or measurable blood pressure. The complete absence of electrical or mechanical cardiac activity is called asystole. Both asystole and PEA are non-perfusing rhythms that do not respond to defibrillation. The management of PEA and asystole focuses on establishing effective CPR and identifying the underlying causes of PEA arrest. See Table 14.1 for some reversible causes of PEA and asystole.

Table 14.1

Reversible causes of PEA and asystole

Hs and Ts	Causes
Hypovolemia	Significant burns, diabetes, gastrointestinal losses, hemorrhage, malignancy, sepsis, trauma
Hypoxia	Upper airway obstruction, hypoventilation (central nervous system dysfunction, neuromuscular disease), pulmonary disease
Hydrogen ions (acidosis)	Diabetes, diarrhea, drug overdose, renal dysfunction, sepsis, shock
Hyper or hypokalemia	Hyperkalemia: drug overdose, renal dysfunction, hemolysis, excessive potassium intake, rhabdomyolysis, major soft tissue injury, tumor lysis syndrome
Hyper or hypokalemia	Hypokalemia: alcohol abuse, diabetes mellitus, diuretics, drug overdose, profound gastrointestinal losses
Hypothermia	Alcohol intoxication, significant burns, drowning, drug overdose, elderly patient, endocrine disease, environmental exposure, spinal cord disease, trauma
Tension pneumothorax	Central venous catheter, mechanical ventilation, pulmonary disease (e.g., asthma, chronic obstructive pulmonary disease), thoracentesis, thoracic trauma
Cardiac tamponade	Post-cardiac surgery, malignancy, post-myocardial infarction, pericarditis, trauma
Pulmonary thromboembolism	Immobilized patients, recent surgical procedures (e.g., orthopedic), peripartum, risk factors for thromboembolic disease, recent trauma, presentation consistent with acute pulmonary embolism
Thrombosis, cardiac	Cardiac arrest
Toxins	History of alcohol or drug abuse, altered mental status, occupational exposure, psychiatric disease