What is the best course of action for a patient with a history of asthma who is experiencing a code blue (cardiac arrest)?

Management of Cardiac Arrest in Asthma Patients

For a patient with asthma experiencing cardiac arrest, initiate standard BLS and ACLS protocols immediately, with critical attention to modified ventilation strategies using lower tidal volumes, slower respiratory rates, and longer expiratory times to prevent worsening air trapping and hyperinflation. 1

Immediate Resuscitation Priorities

Standard CPR with Asthma-Specific Modifications

• Begin high-quality chest compressions and standard ACLS algorithms without delay, as there are no specific alterations to basic cardiac arrest management in asthma patients 1
• Airway management and ventilation become critically important given the underlying respiratory cause of arrest 1
• Administer 100% oxygen immediately during resuscitation efforts 1

Modified Ventilation Strategy

The key pitfall in asthmatic cardiac arrest is aggressive ventilation that worsens outcomes:

• Use lower tidal volumes and lower respiratory rates with increased expiratory time to minimize auto-PEEP and barotrauma 1
• Avoid breath stacking, which increases intrathoracic pressure, decreases venous return and coronary perfusion pressure, and can precipitate or worsen cardiac arrest 1
• If difficulty ventilating occurs with high airway pressures or sudden blood pressure drops, briefly disconnect from the ventilator or pause bag-mask ventilation and compress the thorax to aid exhalation and relieve hyperinflation 1

Identify and Treat Reversible Causes

Tension Pneumothorax

• Evaluate for tension pneumothorax as a rare but potentially reversible cause of arrest in asthma patients 1
• While difficulty ventilating is more likely due to hyperinflation and high intrathoracic pressure, tension pneumothorax must be excluded, particularly in mechanically ventilated patients 1
• Perform immediate needle decompression if tension pneumothorax is identified 1

Severe Bronchospasm and Air Trapping

The underlying pathophysiology involves severe obstruction leading to air trapping, carbon dioxide retention, acute respiratory acidosis, and elevated intrathoracic pressure—all contributing to cardiac arrest 1, 2

Post-Resuscitation Management

Immediate Interventions After ROSC

• Continue 40-60% oxygen to maintain saturation >90% 1, 3
• Administer nebulized salbutamol 5 mg or terbutaline 10 mg via oxygen-driven nebulizer immediately 1, 3
• Give prednisolone 30-60 mg orally or intravenous hydrocortisone 200 mg 1, 3
• Add nebulized ipratropium 0.5 mg if life-threatening features persist 1

Advanced Therapies for Refractory Cases

• Consider intravenous aminophylline 250 mg over 20 minutes if no response to initial bronchodilator therapy (use caution if patient already taking theophyllines) 1, 3
• For patients who remain refractory to conventional resuscitation, extracorporeal membrane oxygenation (ECMO) may be life-saving 4, 5
• ECMO has been successfully used in near-fatal asthma with cardiac arrest, with mode changes (V-A to V-AV to V-V) allowing cardiac support while promoting lung recovery 5

Critical Monitoring Parameters

Immediate Assessment

• Obtain arterial blood gas to assess for severe respiratory acidosis and hypercapnia (PaCO2 often >90 mmHg in asthmatic cardiac arrest) 2
• Measure peak expiratory flow 15-30 minutes after starting treatment and thereafter according to response 1
• Obtain chest radiography to exclude pneumothorax, consolidation, or pulmonary edema 1
• Monitor plasma electrolytes, urea concentrations, and blood count 1

Ongoing Monitoring

• Respiratory status may improve rapidly after resuscitation in asthmatic cardiac arrest—PaCO2 can normalize within 2 hours—but this rapid improvement should not distract from managing hypoxic brain injury 2
• Continue intensive monitoring for deteriorating peak flow, worsening hypoxia (PaO2 <8 kPa) despite 60% oxygen, or hypercapnia (PaCO2 >6 kPa) 1
• Watch for signs of exhaustion, feeble respiration, confusion, drowsiness, or coma requiring ICU admission 1

Common Pitfalls to Avoid

• Never use sedation in asthmatic patients, as it is absolutely contraindicated 1
• Avoid aggressive ventilation with large tidal volumes and high respiratory rates that worsen air trapping 1
• Do not underestimate severity based on rapid respiratory improvement post-arrest—neurological injury from prolonged hypoxia remains the primary determinant of outcome 2
• Recognize that most asthma deaths are preventable, and cardiac arrest represents a failure of earlier intervention 6

Disposition and Follow-up

ICU Admission Criteria

Patients require intensive care if they have: 1

• Deteriorating peak flow despite treatment
• Worsening or persisting hypoxia despite 60% oxygen
• Hypercapnia (PaCO2 >6 kPa)
• Exhaustion, confusion, drowsiness, or coma
• History of cardiac arrest

Ventilation Decisions

• Patients with worsening hypoxia or hypercapnia, drowsiness, unconsciousness, or those who have had respiratory arrest require intubation and mechanical ventilation 1
• Intubation should ideally be performed by an anesthetist 1