What is the initial physical exam approach for a patient in a coma?

Initial Physical Examination of a Comatose Patient

The initial physical exam of a comatose patient must follow a structured ABC approach (Airway, Breathing, Circulation) followed immediately by focused neurological assessment using Glasgow Coma Scale, pupillary examination, and evaluation for signs of herniation. 1, 2

Immediate Stabilization Assessment (First Priority)

Before any detailed neurological examination, assess and secure the following life-threatening conditions:

• Airway patency: Check for irregular breathing, drooling, or pooling of saliva/vomit in the mouth, which indicate respiratory depression or airway obstruction 1
• Breathing adequacy: Assess for tachypnea, increased work of breathing, irregular respirations, or hypoxia (oxygen saturation <95%) 1
• Circulatory status: Measure pulse rate and volume, blood pressure (maintain systolic BP >110 mmHg in trauma, >90 mmHg generally), capillary refill time, and temperature gradient 1, 2
• Immediate interventions: Provide supplemental oxygen to maintain SaO₂ >95%, establish IV access, and prepare for intubation if airway protection is compromised 1, 2

Focused Neurological Examination

Level of Consciousness Assessment

Calculate the complete Glasgow Coma Scale score, documenting individual components (Eye, Motor, Verbal) rather than just the sum:

• Eye opening response (1-4 points) 1, 3
• Motor response (1-6 points) - the most prognostically important component 4
• Verbal response (1-5 points) 1, 3
• GCS ≤8 defines severe coma requiring immediate neurosurgical consultation 1

Pupillary Examination

Assess pupillary size, symmetry, and reactivity to light bilaterally:

• Pupillary changes or asymmetry suggest herniation and require immediate intervention 3, 4
• Document pupil size in millimeters and reactivity (brisk, sluggish, or absent) 2, 4
• Fixed dilated pupils indicate severe brainstem dysfunction 5

Brainstem Reflex Testing

Evaluate oculomotor function and brainstem integrity:

• Oculocephalic reflex (doll's eyes) - only if cervical spine injury is excluded 5, 6
• Corneal reflex - tests pontine function 5, 6
• Gag and cough reflexes - assess medullary function and airway protection 6

Motor Examination

Assess motor responses systematically:

• Spontaneous movements - note any asymmetry suggesting focal lesions 5, 6
• Response to painful stimuli - apply central (sternal rub, supraorbital pressure) and peripheral stimuli 5, 6
• Posturing patterns: Decorticate (flexor) versus decerebrate (extensor) posturing indicates level of brain dysfunction 5, 6
• Focal deficits suggest structural lesions requiring imaging 1, 2

Vital Signs and Physiological Parameters

Measure and document the "fifth vital sign" (oxygen saturation) along with traditional vital signs:

• Respiratory rate and pattern - Cheyne-Stokes, central neurogenic hyperventilation, or ataxic breathing patterns provide localization 5, 6
• Blood pressure - both hypotension and severe hypertension (Cushing's response) are critical 1
• Heart rate and rhythm 1
• Temperature - hyperthermia or hypothermia may indicate specific etiologies 1, 5
• Oxygen saturation - must be >95% to prevent secondary brain injury 1, 2

Physical Examination for Etiology

Perform targeted examination to identify reversible causes:

• Head and neck: Examine for signs of trauma (Battle's sign, raccoon eyes, hemotympanum, CSF rhinorrhea/otorrhea), nuchal rigidity suggesting meningitis or subarachnoid hemorrhage 1, 2
• Skin: Look for needle tracks, rashes, petechiae, or signs of liver disease 5, 7
• Breath odor: Fruity (ketoacidosis), uremic, or alcohol 5
• Cardiac examination: Arrhythmias or murmurs suggesting embolic stroke 7
• Abdominal examination: Hepatomegaly or other signs of metabolic disease 5

Serial Monitoring Protocol

Establish a structured reassessment schedule:

• Every 15 minutes for the first 2 hours in patients with structural lesions 3
• Hourly for the following 12 hours 3
• Any decline of ≥2 points in GCS warrants immediate repeat imaging 3, 4
• Document trends rather than single measurements - declining scores indicate deterioration requiring intervention 3, 4

Critical Pitfalls to Avoid

Common errors that worsen outcomes:

• Never delay airway protection to complete neurological examination in patients with irregular breathing or absent gag reflex 1, 2
• Do not administer long-acting sedatives or paralytics before neurosurgical evaluation, as this masks clinical deterioration 3
• Never obtain oximetry readings on room air in patients who clearly require oxygen therapy 1
• Do not attribute coma solely to intoxication without excluding structural lesions - obtain CT imaging if any doubt exists 7
• Avoid hypotension (systolic BP <90 mmHg) and hypoxia (SaO₂ <90%) as these secondary insults dramatically worsen outcomes 1