Asthma (OSCE)

Clinical Assessment of Asthma

ABC, Vitals

 * SaO2

Fingers

 * cyanosis

Chest

 * ↑AP diameter (barrel chest)
 * asymmetry of shape and movement

Work of Breathing

 * RR, HR
 * POSTURE (tripoding)
 * level of comfort, speaking full sentences, diaphoresis
 * accessory muscle use (SCM, shoulder elevation), nasal flaring, pursed lips

Signs of RESPIRATORY EXHAUSTION or impending FAILURE

 * ↓ LOC, ↓ amplitude of pulse
 * central cyanosis (tongue, oral mucosa)
 * intercostals, subcostal, and supraclavicular indrawing
 * pulsus paradoxus (> 18 mm Hg drop with inspiration suggests very severe asthma)
 * paradoxical movement of the diaphragm

Palpation

 * tracheal tug
 * symmetrically ↓ chest expansion
 * ↓ tactile fremitus (due to hyperinflation)

Percussion

 * hyperresonance - percuss anteriorly and posteriorly, compare L and R
 * ↓ diaphragmatic excursion (normal is 5 - 6 cm)
 * inferior displacement of diaphragm due to hyperinflation

Auscultation

 * listen to each lobe, compare L and R
 * major fissure: T3 posteriorly → 4th ICS MAL → 6th rib MCL
 * minor fissure: 5th ICS MAL → 4th ICS parasternal
 * ↓ AE
 * prolonged expiratory phase
 * forced expiration with bell on trachea (normal < 5 s, abnormal > 6 s)
 * wheezing
 * may be absent in severe asthma
 * consolidation
 * suggests pneumonia as trigger for acute attack

Special Tests

 * peak expiratory flow rate (PEFR): normal male 600, female 400, sick < 150
 * PFT - obstructive pattern (↓ flow rates, ↑ volumes)
 * ABG - pH < 7.3, PO2 < 60, PCO2 > 45