Neurocritical Care – The Lay Medical Man

Bedside Test	Procedure	Normal / Reassuring Value	Clinical Significance (Red Flag)
Clinical Assessment	Observe for signs of respiratory distress and bulbar weakness (speech, swallowing).	No accessory muscle use, effortless breathing, strong cough, clear voice.	Tachypnea, accessory muscle use, paradoxical breathing, weak “boggy” cough, slurred/fading voice.
Vital Capacity (VC)	Patient takes a maximal inhalation and exhales fully into a bedside spirometer.	> 20 mL/kg (ideal body weight)	< 15-20 mL/kg, or a declining trend during the breathing trial.
Negative Inspiratory Force (NIF) / MIP	Patient makes a maximal inspiratory effort against an occluded airway for ~20 seconds.	More negative than -30 cm H₂O	Less negative than -30 cm H₂O (e.g., -25, -20), or a worsening trend.
Single Breath Count	Patient takes a deep breath and counts aloud steadily (e.g., “1-one-thousand, 2-one-thousand…”).	> 25	< 15-20. Indicates severely reduced vital capacity.
Head Lift Test	Patient lies supine and lifts their head off the bed, holding the position as long as possible.	> 30 seconds	< 20 seconds. Correlates with significant diaphragmatic weakness.
Breath-Holding Time	After a maximal inhalation, the patient holds their breath for as long as possible.	> 30 seconds	< 20 seconds. Suggests poor respiratory reserve.

The Lay Medical Man