Hypoxemic reperfusion after 120 mins of intestinal ischemia attenuates the histopathologic and inflammatory response

Crit Care Med. 2004 Nov;32(11):2279-83. doi: 10.1097/01.ccm.0000145582.03345.c8.


Objective: It has been suggested that reactive oxygen species play a pivotal role in the initial organ-tissue injury during reperfusion, eliciting inflammatory reaction and multiple organ failure. It was investigated if hypoxemic reperfusion attenuates tissue injury and inflammatory response.

Design: Randomized animal study.

Setting: Medical school laboratory.

Subjects: Twenty-five male pigs weighing 25-28 kg.

Interventions: Pigs were subjected to 120 mins of intestinal ischemia by clamping the superior mesenteric artery. Upon declamping, the animals were randomly assigned to receive either hypoxemic reperfusion (HR group, n = 9) reperfused with a Pao2 = 30-35 or normoxemic reperfusion (control group, n = 16) reperfused with a Pao2 = 100 mm Hg for 120 mins. Fluids without inotropes were given to combat circulatory shock during reperfusion.

Measurements and main results: Portal blood and intestinal and lung biopsies were collected at baseline, end of ischemia, and end of reperfusion. Histopathologic changes were scored, and interleukin-1beta, qualitative Limulus amebocyte, lysate test, and Pao2/Fio2 were measured. Eight of 16 animals of the control group and seven of nine of the HR group survived (p = .22). At the end of reperfusion, the intestinal (p = .004) and lung (p = .028) pathologic scores were lower in the HR group compared with controls. The only significant difference in concentration of interleukin-1beta in the portal blood between the two animal groups occurred 120 mins after reperfusion (p = .006). The number of HR animals with a positive Limulus test was significantly smaller compared with controls at 60 (p = .041) and 120 (p = .07) mins of reperfusion. During the period of ischemia, the Pao2/Fio2 decreased similarly in the control and HR group, whereas after 120 mins of reperfusion the rate was significantly higher in the HR group.

Conclusions: Hypoxemic reperfusion represents an intervention that may attenuate the triggering of multifactorial cascade and organ tissue injury.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biopsy
  • Blood Gas Analysis
  • Disease Models, Animal*
  • Fluid Therapy / methods
  • Hypoxia / complications*
  • Hypoxia / metabolism
  • Ileum / blood supply*
  • Ileum / pathology
  • Inflammation
  • Interleukin-1 / blood
  • Ischemia / therapy*
  • Lung / pathology
  • Male
  • Mesenteric Artery, Superior
  • Multiple Organ Failure / etiology
  • Multiple Organ Failure / pathology
  • Multiple Organ Failure / prevention & control
  • Oxygen / blood
  • Random Allocation
  • Reactive Oxygen Species / metabolism
  • Reperfusion / adverse effects
  • Reperfusion / methods*
  • Reperfusion Injury / etiology*
  • Reperfusion Injury / pathology
  • Reperfusion Injury / prevention & control*
  • Swine
  • Systemic Inflammatory Response Syndrome / etiology
  • Systemic Inflammatory Response Syndrome / prevention & control
  • Time Factors
  • Treatment Outcome


  • Interleukin-1
  • Reactive Oxygen Species
  • Oxygen