Effects of the stable prostacyclin analogue iloprost on mesenteric blood flow in porcine endotoxic shock.
OBJECTIVE
To determine the effects of the stable prostacyclin analog, iloprost, in a porcine model of endotoxin-induced mesenteric ischemia.


METHODS
Prospective, experimental, randomized, controlled study.


METHODS
Animal research laboratory at a university medical center.


METHODS
Pigs were randomized to receive a constant infusion of iloprost (0.18 microg/kg/min) or an equivalent amount of carrier solution (normal saline) 30 mins before being infused with endotoxin (100 microg/kg over 1 hr). The infusion with iloprost or carrier solution was continued for the duration of the experiment.


RESULTS
Twelve pigs (six per group), weighing between 20 and 22 kg, underwent laparotomy during which a magnetic flowprobe was placed around the superior mesenteric artery and an ileal tonometer was inserted. Thirty minutes before they were infused with endotoxin, the animals were randomized to receive intravenous iloprost or normal saline. Endotoxin was infused centrally over a 60-min period. Animals received normal saline at a rate of 1.2 mL/kg/min which was begun at the start of the endotoxin infusion. Data were measured at the end of the endotoxin infusion (E60) and 1 hr later (E120). Mean arterial pressure was not affected by the dosage of iloprost used in this experiment. After resuscitation, the cardiac output returned to baseline in the iloprost-treated group but remained decreased in the control group (2.6 +/- 0.5 vs. 1.6 +/- 0.4 L/min). Superior mesenteric blood flow increased 34% above baseline levels in animals pretreated with iloprost (from 363 +/- 85 to 485 +/- 81 mL/min). The superior mesenteric PCO2 was significantly higher (53 +/- 9 vs. 40 +/- 5 torr; 7.1 +/- 1.2 vs. 5.3 +/- 0.7 kPa) and the ileal intramucosal pH was significantly lower (7.07 +/- .28 vs. 7.44 +/- .23) in the control group than in the iloprost-treated group.


CONCLUSIONS
Pretreatment with intravenous iloprost effectively increased intestinal blood flow in this model of endotoxin-induced mesenteric ischemia. This action of the drug resulted in an attenuation of ileal intracellular acidosis. Since low-dose iloprost had no effect on mean arterial pressure, it may be a useful adjunct in the treatment of sepsis and septic shock.
Manasia
A
A
Department of Surgery, Mount Sinai Medical Center, City University of New York, New York 10029, USA.
Kang
H
H
Hannon
E
E
Lu
Y
Y
Oropello
J
J
Leibowitz
A
A
Stein
J
J
Benjamin
E
E
D000138:Acidosis; D000818:Animals; D019446:Endotoxemia / Q000188:drug therapy / Q000503:physiopathology*; D005069:Evaluation Studies as Topic; D006439:Hemodynamics; D016285:Iloprost / Q000494:pharmacology*; D007422:Intestines / Q000098:blood supply; D007511:Ischemia / Q000209:etiology / Q000517:prevention & control; D011446:Prospective Studies; D011897:Random Allocation; D013152:Splanchnic Circulation / Q000187:drug effects*; D013552:Swine; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; D016285:Iloprost