Vital signs may give a clue to the etiology. Hypothermia (including metabolic causes such as hypothyroidism, hypoadrenalism, hypoglycemia and sepsis) and hyperthermia may all cause a decreased level of consciousness.
Tachyarrhythmias and bradyarrhythmias suggests cardiac disease. Hyperventilation
is seen in diabetic ketoacidosis, uremia and cirrhosis.
Hypoventilation is common in opiate drug overdoses and in pulmonary disease. Hypotension requires searching for the etiology of shock. Hypertension suggests hypertensive encephalopathy or drugs such as cocaine.
alcohol on the breath is noted, as is the fruity odor of diabetic ketoacidosis. A petroleum or garlic odor is sometimes seen in organophosphate pesticide poisoning.
evidence of trauma should be sought, such as bruising or lacerations of the head and face. A basilar skull fracture may cause cerebrospinal fluid to leak from the nose or ear, or the extravasation of blood in the middle ear (hemotympanum) into the skin around the eyes (raccoon eyes) or over the mastoid process (Battle’s sign).
neck stiffness, Kernig and Brudzinki’s signs may indicate meningitis. Jugular venous distention is noted, as is the size of the thyroid gland.
signs of trauma should be sought, as above. The heart and lungs are evaluated. Decreased breath sounds on one side may indicate a pneumothorax or hemothorax. Jugular venous distention plus low blood pressure may suggest cardiac tamponade.
jaundice and a distended abdomen is seen in alcoholic liver disease. Abrasions, decreased bowel sounds, tenderness and rigidity suggest trauma with possible internal hemorrhage.
the Glasgow Coma Scale is assessed frequently for changes.
abrasions suggest trauma, jaundice suggests sequelae of liver disease, needle-tracks suggest drug abuse. Profuse sweating is seen with organophosphate pesticide poisoning. Cold sweats are present in a patient suffering a heart attack. A petechial or purpuric rash should alert one to meningococcemia.