RECTAL PH MEASUREMENT IN TRACKING CARDIAC-PERFORMANCE IN A HEMORRHAGIC-SHOCK MODEL

Objective and Design: We evaluated the utility of rectal mucosal pH me asurement for tracking cardiac performance in hemorrhagic shock as com pared with gastric tonometry. Materials and Methods: Hemorrhagic shock was induced in five adult swine to a mean arterial pressure of 45-65 mm Hg. Hypotension was maintained for 30 minutes, resuscitation was ac complished with the shed blood and lactated Ringer's solution (3x bloo d volume). Gastric tonometry, rectal pH, and oxygen transport data wer e obtained at baseline, 0, and 30 minutes after onset of hypotension a nd after resuscitation. Results: Intramucosal pH readings from gastric tonometry and rectal mucosal pH both showed a significant change from baseline to 0 and 30 minutes after onset of hypotension. Data after r esuscitation were found to be statistically the same as baseline value s. Conclusions: Rectal mucosal pH tracks cardiac performance as well a s does gastric tonometry in hemorrhagic shock without as many limitati ons.