A Report on Associations Among Gastric pH, Bleeding, Duodenogastric Reflux, and Outcomes After Trauma

Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston-Medical School, Houston, Texas, USA.
The Journal of trauma (Impact Factor: 2.96). 01/2008; 64(1):105-10. DOI: 10.1097/TA.0b013e31815ebd99
Source: PubMed


The pathogenesis of multiple organ failure (MOF) in trauma patients may involve the gastrointestinal tract, but its exact origins remain elusive. In a prospective study, the gastric fluid of major torso trauma patients was examined for evidence of duodenogastric reflux and potential gastric injury, and was compared with patient outcomes regarding MOF.
Patient samples were collected daily for 4 days by nasogastric tube and analyzed for pH, hemoglobin, and bile acid. Blood was collected for analysis of C-reactive protein (CRP). Outcomes were recorded for the presence or absence of MOF.
The results showed that most patients exhibited alkaline gastric contents (pH >/=4.9) and elevated levels of hemoglobin immediately after the trauma. Although non-MOF patients demonstrated a decline of both mean gastric pH and bleeding by day 4, MOF patients maintained significant elevations in pH during this time period. Mean total bile acid levels were increased in all patients, signifying the presence of duodenogastric reflux. However, there were no clear differences in mean bile acid concentrations between MOF and non-MOF patients over time, although MOF patients tended to exhibit higher levels. All patients showed a progressive rise in serum CRP during the first 24 hours after trauma, which was maintained for 4 days. The initial rise in serum CRP in MOF patients was delayed compared with that in non-MOF patients.
We conclude that duodenogastric reflux occurs in trauma patients in the first few days after trauma and may contribute to elevated gastric pH and bleeding. Further study is needed to verify whether monitoring the gastric juice of trauma patients during the first several days of hospitalization, for alkaline pH and excessive blood in the gastric lumen, could lead to better assessments of patient status.

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