An abbreviated mental status examination was devised and used to study 35 surgical patients requiring a stay in the intensive care unit. Test scores of 24 normal patients fell within a narrow range with a mean of 9.0 (SD ± 0.8) without significant change in score with repeated testing. Nine delirious patients, demonstrating global cognitive impairment, had a mean test score of 2.4 (SD ± 1.0). These patients demonstrated serious and often lethal physiologic abnormalities, most commonly hypoxia or sepsis. Two patients with prominent hallucinations showed selective cognitive impairment in spatial orientation. Their test scores were normal and environmental factors such as sleep deprivation and monotony appeared prominent. Mental status testing is a practical means of accomplishing early detection and effective treatment of the causes of delirium in these patients.
Katz NM, Agle DP, DePalma RG, DeCosse JJ. Delirium in Surgical Patients Under Intensive CareUtility of Mental Status Examination. Arch Surg. 1972;104(3):310-313. doi:10.1001/archsurg.1972.04180030058013