Splanchnic oxygenation in patients undergoing abdominal aortic aneurysm repair and volume expansion with eloHAES

Abstract

Background: Gastric intramucosal pH (pHi), a surrogate marker of splanchnic oxygenation, falls following abdominal aortic aneurysm surgery. Aim: To investigate the effects of volume expansion with hydroxyethyl starch (eloHAES) on splanchnic perfusion compared to another colloid such as gelofusine. Patients and methods: Twenty-two consecutive patients undergoing AAA repair were randomised to receive either eloHAES or gelofusine as plasma expanders. Tissue oxygenation was monitored (10 gelofusine and 12 eloHAES) indirectly by measuring pHi using a nasogastric tonometer. Results: Compared to the eloHAES group, the fall in pHi was significantly greater in the gelofusine group at clamp release (7.29 vs 7.33, P=0.003) and at 4 h following clamp release (7.29 vs 7.33, P=0.03). There was a good inverse correlation between the lowest pHi and the peak serum interleukin-6 (rs=−0.47, P=0.03). By multivariate analysis, the only factor that influenced the pHi was the type of colloid used (F=5.54, P=0.005). The eloHAES treated patients required significantly less colloid on the first postoperative day (3175±175 vs 4065±269 ml, P=0.01). Conclusion: In patients undergoing abdominal aortic aneurysm repair, plasma expansion with eloHAES improves microvascular perfusion and splanchnic oxygenation.