title: Ultradian cardiac rhthms in surgical intensive care unit patients.
abstract: Several reports have suggested that heart rate may be regulated by an ultradian biological rhythm with a period of about 90--100 min. Blood pressure and heart rate were collected from 10 Surgical Intensive Care patients at 5-min intervals and analyzed by computer. No 90-min rhthms were found, indicating this rhythm has no significant influence on heart rate or blood pressure in postsurgical patients.
mesh_terms: D000328:Adult; D000368:Aged; D001683:Biological Clocks; D001794:Blood Pressure; D006339:Heart Rate; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D012931:Social Environment; D013503:Surgery Department, Hospital; D013514:Surgical Procedures, Operative; D013997:Time Factors