Crowing respirations are slow, deep inspirations accompanied by a high-pitched “crowing” sound. They are most classically observed during the paroxysmal stage of pertussis (whooping cough).

• The sound is produced by turbulent airflow through a partially obstructed upper airway, usually the larynx.

• Also referred to as the “whoop” in pertussis.

• May occur in other conditions causing upper airway obstruction, such as laryngomalacia, croup, or foreign body aspiration, but with differing clinical context.

Pathophysiology

• Upper airway obstruction: Narrowing of the larynx or trachea leads to turbulent airflow.

• Forceful inspiration: Following intense paroxysmal coughing, the patient attempts to inhale deeply through a partially closed glottis.

• Characteristic sound generation: The high-pitched “crowing” results from the vibration of airway tissues as air passes through a narrowed segment.

• Pertussis-specific mechanism: Bordetella pertussis infection causes paroxysms of cough due to toxin-mediated inflammation and increased mucus production, culminating in the inspiratory whoop.

Examination Technique

Patient Observation

• Listen carefully during the paroxysmal coughing stage.

• Observe for cyanosis, distress, or accessory muscle use.

Auscultation

• Use a stethoscope to differentiate from stridor or wheezing.

• Note the timing of the whoop (inspiratory phase following coughing paroxysm).

Assessment Notes

• Severity may vary with age; infants <6 months may have apneic episodes instead of classic whoop.

• Evaluate for associated signs of respiratory distress: nasal flaring, retractions, or hypoxia.

Clinical Utility

• Diagnostic clue: Strongly suggestive of pertussis in children and adolescents.

• Disease staging: Appears during the paroxysmal stage, after the catarrhal stage of mild upper respiratory symptoms.

• Monitoring severity: Frequency and intensity of crowing respirations help assess airway compromise and disease progression.

Differential Diagnosis

Pediatric considerations

• Classic whoop most pronounced in children >6 months.

• Infants may present primarily with apnea, cyanosis, or gagging.

• Early recognition is crucial to prevent complications: pneumonia, seizures, or hypoxic injury.

Geriatric considerations

• Rarely relevant; pertussis is less likely to produce classical crowing in adults, who may present with chronic cough.

Limitations

• Not always present in very young infants or partially vaccinated children.

• Similar inspiratory sounds may occur with other upper airway pathologies, requiring careful differentiation.

• Clinical diagnosis should be confirmed with laboratory testing (PCR, culture, or serology for Bordetella pertussis).

Patient counseling

• Explain that the “crowing” sound is a hallmark of pertussis and indicates the paroxysmal stage of disease.

• Stress the importance of medical evaluation and monitoring, especially in infants.

• Discuss vaccination as a preventive measure.

• Educate caregivers about hydration, minimizing airway irritation, and avoiding exposure to others.

Conclusion

Crowing respirations, or the “whoop,” are a characteristic inspiratory sound indicative of pertussis or upper airway obstruction. Recognition of this sign is essential for early diagnosis, appropriate management, and prevention of complications, particularly in pediatric populations.

References

1. Cherry JD. Pertussis in Children: Clinical Manifestations and Diagnosis. Pediatr Infect Dis J. 2000;19(7 Suppl):S39–S44.

2. Bisgard KM, et al. Pertussis: Whooping Cough in Children and Adults. Clin Microbiol Rev. 2004;17(2):308–332.

3. American Academy of Pediatrics. Red Book: 2021 Report of the Committee on Infectious Diseases. 32nd ed. Elk Grove Village, IL: AAP; 2021.

4. Munoz FM, et al. Pertussis in Infants: Diagnosis, Management, and Prevention. Clin Microbiol Rev. 2016;29(3):449–490.

5. Cherry JD. Clinical features and diagnosis of pertussis. Pediatr Infect Dis J. 2012;31(1):35–39.