Vascular tone in patients with hemorrhagic shock.
BACKGROUND
In hemorrhagic shock, the alterations in arterial vascular tone, which are primarily regulated by adrenosympathetic influences are compensatory responses to bleeding.


OBJECTIVE
The aim of this study was to evaluate vascular tone expressed by the volume elastic modulus (Ev) as a clinical monitor to detect the hypovolemic state.


METHODS
Thirteen patients with hemorrhagic shock were studied. The initial Ev measurement was performed at arrival, and subsequent measurements were obtained 4 and 12 hours after arrival. Patients were divided into two groups by cluster analysis by using the Ev values at arrival and 4 hours after arrival. Circulatory parameters, the clinical course, and fluid were compared.


RESULTS
The Ev values were identical at admission (cluster I vs. II: 456.4+/-197.1 vs 566.1+/-234.1 mm Hg, mean +/- SD). After 4 hours of fluid resuscitation, all patients were recovered from shock. In cluster I, the Ev remained high at 4 hours (523.4+/-75.1 mm Hg) and invasive treatments for hemostasis were required. In cluster II, the Ev significantly decreased at 4 hours (182.8+/-70.7 mm Hg, p < 0.01) and clinical courses were eventless thereafter. During 4 to 12 hours, more fluid was given in cluster I (p < 0.05). At 12 hours after arrival, the Ev values were identical in both clusters.


CONCLUSIONS
These data demonstrate that the Ev increases in hemorrhagic shock. Furthermore, normotensive hypovolemic conditions generated by persistent bleeding can be detected by measuring the Ev.
Miyagatani
Y
Y
Department of Traumatology and Critical Care Medicine, School of Health Sciences, Kyorin University, Tokyo, Japan.
Yukioka
T
T
Ohta
S
S
Ohta
S
S
Matsuda
H
H
Shimazu
H
H
Shimazaki
S
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D001158:Arteries / Q000503:physiopathology; D001811:Blood Volume Determination; D016000:Cluster Analysis; D004867:Equipment Design; D005260:Female; D005385:Fingers / Q000098:blood supply*; D006439:Hemodynamics; D006801:Humans; D015601:Injury Severity Score; D007552:Isotonic Solutions / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009991:Oscillometry; D010991:Plethysmography / Q000295:instrumentation; D000077325:Ringer's Lactate; D012771:Shock, Hemorrhagic / Q000503:physiopathology* / Q000628:therapy; D014947:Wounds and Injuries / Q000145:classification / Q000503:physiopathology* / Q000628:therapy
D007552:Isotonic Solutions; D000077325:Ringer's Lactate