T H Gould1, K Grace, G Thorne, M Thomas. 1. Sir Humphrey Davy Department of Anaesthesia, Bristol Royal Infirmary, Marlborough Street, Bristol BS8 2HW, UK.
Abstract
BACKGROUND: The effect of thoracic epidural block on splanchnic blood flow is unclear. It remains to be resolved if sympathetic block, increases or decreases regional splanchnic blood flow and whether regional splanchnic flow becomes dependent on cardiac output or perfusion pressure. A clear understanding of the regional haemodynamic consequences of an epidural block may modify practice with respect to epidural anaesthesia. METHODS: Fifteen patients, who underwent anterior resection for rectal cancer, had invasive intraoperative monitoring of arterial pressure, central venous pressure, cardiac output, inferior mesenteric artery flow (Doppler flow probe), and colonic serosal red cell flux (laser Doppler probe), while an epidural block was established with local anaesthetic. In three consecutive time periods, arterial pressure was first allowed to fall (to a mean arterial pressure of 60 mm Hg), then treated with colloid fluid resuscitation and finally by vasopressors until the pre-epidural arterial pressure had been restored. RESULTS: On induction of epidural block, there was a reduction in mean colonic serosal red cell flux to 65% and inferior mesenteric artery flow to 80% (mean) of pre-epidural levels. There was a strong association between mean arterial pressure and both measured inferior mesenteric artery blood flow (P < 0.004) and colonic serosal red cell flux (P < 0.0001). Changes in cardiac output were poorly associated with either inferior mesenteric artery blood flow (P = 0.638) or colonic serosal red cell flux (P = 0.265). Inferior mesenteric artery blood flow and colonic serosal red cell flux were restored to pre-epidural levels after arterial pressure had been improved with a vasopressor. CONCLUSION: Once intraoperative epidural block has been established, colonic serosal red cell flux and inferior mesenteric artery flow are more closely associated with changes in mean arterial pressure than changes in cardiac output. The measured reduction in colonic flow does not respond to an increase in cardiac output with fluid resuscitation, but requires the use of a vasopressor to increase arterial pressure, before colonic blood flow is improved.
BACKGROUND: The effect of thoracic epidural block on splanchnic blood flow is unclear. It remains to be resolved if sympathetic block, increases or decreases regional splanchnic blood flow and whether regional splanchnic flow becomes dependent on cardiac output or perfusion pressure. A clear understanding of the regional haemodynamic consequences of an epidural block may modify practice with respect to epidural anaesthesia. METHODS: Fifteen patients, who underwent anterior resection for rectal cancer, had invasive intraoperative monitoring of arterial pressure, central venous pressure, cardiac output, inferior mesenteric artery flow (Doppler flow probe), and colonic serosal red cell flux (laser Doppler probe), while an epidural block was established with local anaesthetic. In three consecutive time periods, arterial pressure was first allowed to fall (to a mean arterial pressure of 60 mm Hg), then treated with colloid fluid resuscitation and finally by vasopressors until the pre-epidural arterial pressure had been restored. RESULTS: On induction of epidural block, there was a reduction in mean colonic serosal red cell flux to 65% and inferior mesenteric artery flow to 80% (mean) of pre-epidural levels. There was a strong association between mean arterial pressure and both measured inferior mesenteric artery blood flow (P < 0.004) and colonic serosal red cell flux (P < 0.0001). Changes in cardiac output were poorly associated with either inferior mesenteric artery blood flow (P = 0.638) or colonic serosal red cell flux (P = 0.265). Inferior mesenteric artery blood flow and colonic serosal red cell flux were restored to pre-epidural levels after arterial pressure had been improved with a vasopressor. CONCLUSION: Once intraoperative epidural block has been established, colonic serosal red cell flux and inferior mesenteric artery flow are more closely associated with changes in mean arterial pressure than changes in cardiac output. The measured reduction in colonic flow does not respond to an increase in cardiac output with fluid resuscitation, but requires the use of a vasopressor to increase arterial pressure, before colonic blood flow is improved.
Authors: Joseph C Carmichael; Deborah S Keller; Gabriele Baldini; Liliana Bordeianou; Eric Weiss; Lawrence Lee; Marylise Boutros; James McClane; Scott R Steele; Liane S Feldman Journal: Surg Endosc Date: 2017-08-03 Impact factor: 4.584
Authors: U O Gustafsson; M J Scott; W Schwenk; N Demartines; D Roulin; N Francis; C E McNaught; J Macfie; A S Liberman; M Soop; A Hill; R H Kennedy; D N Lobo; K Fearon; O Ljungqvist Journal: World J Surg Date: 2013-02 Impact factor: 3.352
Authors: J Nygren; J Thacker; F Carli; K C H Fearon; S Norderval; D N Lobo; O Ljungqvist; M Soop; J Ramirez Journal: World J Surg Date: 2013-02 Impact factor: 3.352
Authors: A L M Tavy; A F J de Bruin; K van der Sloot; E C Boerma; C Ince; P G Noordzij; D Boerma; M van Iterson Journal: World J Surg Date: 2018-12 Impact factor: 3.352
Authors: F Ris; J M Findlay; R Hompes; A Rashid; J Warwick; C Cunningham; O Jones; N Crabtree; I Lindsey Journal: Ann R Coll Surg Engl Date: 2014-11 Impact factor: 1.891
Authors: Jörn Adolphs; Diego K Schmidt; Ines Korsukewitz; Britta Kamin; Helmut Habazettl; Michael Schäfer; Martin Welte Journal: Intensive Care Med Date: 2004-08-26 Impact factor: 17.440
Authors: Tanya Zakrison; Bartolomeu A Nascimento; Lorraine N Tremblay; Alex Kiss; Sandro B Rizoli Journal: World J Surg Date: 2007-08 Impact factor: 3.352