Perioperative plasma endothelin-1 concentrations and vasoconstriction during prolonged plastic surgical procedures

Abstract

The role of endothelin-1, a potent vasoconstrictor released by vascular endothelium, in the vasoconstriction that develops after prolonged operations is not clear. This study was performed in order to determine if there was any relationship between endothelin-1 and the degree of vasoconstriction during prolonged plastic surgery. Plasma concentrations of endothelin-1, skin-forearm temperature gradient (Tgrad), rectal temperature, mean arterial pressure (MAP) and heart rate (HR) were measured at nine predetermined times before, during and after operation in nine women undergoing breast reconstruction with a pedicled transverse rectus abdominis musculocutaneous flap. Development of cutaneous or fat necrosis of the flap was assessed clinically and with ultrasound. Concentrations of endothelin-1 before induction were increased (median 8.9 (25-75% quartiles 5.5-12.5) pg ml-1). During operation they were approximately 3 pg ml-1 and after operation approximately 5 pg ml-1. Tgrad was approximately 4 degrees C before induction and after operation, indicating marked vasoconstriction; during operation it was about zero, indicating vasodilatation. There was a statistically significant correlation between endothelin-1 concentrations and Tgrad (Spearman non-linear correlation) (r = 0.32, P = 0.004) and between endothelin-1 and MAP (r = 0.25, P = 0.02), but not between endothelin-1 and HR or development of minor cutaneous or fat necrosis of the flap (five patients). We conclude that increased plasma concentration of endothelin-1 is associated with the extent of peripheral vasoconstriction.

Effect of age and body weight on neurohumoral variables in healthy Cavalier King Charles Spaniels

“…In contrast to this, ET-1 infusion is reported to decrease HR. 19 Our result is also in contrast to a previous study in humans, 37 whereby ET-1 did not correlate to HR perioperatively during plastic surgery. One explanation could be that the variation in heart rate in our population was higher.…”

“…Plasma immunoreactive ET-1 was measured by use of RIA after extraction as described earlier, 37,38 using synthetic ET-1 o and endothelin antiserum raised in rabbits. Recovery of synthetic ET-1 added to plasma was 84%.…”

Pulmonary metabolism of endothelin 1 during on-pump and beating heart coronary artery bypass operations

“…The exact mechanisms behind the increased ET-1 concentration after CPB are unknown. However, surgical stress 20 and hypothermia 21 are known to increase ET-1 levels. We failed to find any significant increase in both mixed venous and arterial ET-1 levels in the beating heart groups.…”

Heart rate variability in patients recovering from general anaesthesia

“…There is circumstantial evidence that stress hormonal activation may be an important modulator of HRV. Most studies have concentrated on the effects of the autonomic nervous system on HRV, but have ignored the fact that in situations of high sympathetic tone there are commonly coexisting elevations in vasopressin, renin, angiotensin II, corticosteroids and a number of autocoids controlling vasomotor tone [15,16]. These hormones may act in at least two ways.…”