title: Vagal slowing of the heart during haemorrhage: observations from 20 consecutive hypotensive patients.
abstract: Heart rate and arterial blood pressure were monitored in 20 consecutive patients during resuscitation from haemorrhagic shock. The mean blood loss (2.3 (SEM 0.3) 1) corresponded to 36(4)% of their estimated mean blood volume. During shock the mean blood pressure was 81/55 (3/2) mm Hg and heart rate 73 (3) beats/min. Administration of blood and crystalloids resulted in immediate increases to 111/72 (2/2) mm Hg and 102 (3) beats/min followed by steady state values of 131/79 (6/3) mm Hg and 82 (2) beats/min. In three otherwise healthy patients plasma concentrations of the vagally regulated hormone pancreatic polypeptide rose from resting values of 64-77 pmol/l (272-327 pg/ml) to 198-280 pmol/l (842-1190 pg/ml). These findings suggest that reversible hypotensive hypovolaemic shock is characterised by a decrease in heart rate conceivably reflecting an increase in vagal tone.
authors.forename: K
authors.initials: K
authors.lastname: Sander-Jensen
authors.forename: N H
authors.initials: NH
authors.lastname: Secher
authors.forename: P
authors.initials: P
authors.lastname: Bie
authors.forename: J
authors.initials: J
authors.lastname: Warberg
authors.forename: T W
authors.initials: TW
authors.lastname: Schwartz
mesh_terms: D000328:Adult; D000368:Aged; D001127:Arginine Vasopressin / Q000097:blood; D001794:Blood Pressure; D001803:Blood Transfusion; D005260:Female; D006339:Heart Rate; D006470:Hemorrhage / Q000097:blood / Q000503:physiopathology*; D006801:Humans; D007022:Hypotension / Q000097:blood / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010191:Pancreatic Polypeptide / Q000097:blood; D014630:Vagus Nerve / Q000503:physiopathology*
chemical_list: D001127:Arginine Vasopressin; D010191:Pancreatic Polypeptide