Variables Associated with Gastric Acidity in Critically Ill Patients: An Approach to Prescribe Acid-Suppressing Medications

Measurement of gastric pH potentially could be benefit to apply in various medical fields such as stress-related mucosal damage (SRMD) management especially in critically ill patients. So, we designed this study to measure gastric acidity in high-risk patients for gastrointestinal (GI) bleeding in intensive care unit (ICU), and evaluate variables associated to gastric pH. In a prospective clinical study, gastric secretions of 200 patients in ICU were aspirated if they received stress ulcer prophylaxis (SUP) or had indication to receive it, and had nasogastric tube to aspirate gastric secretion. Thereafter, the acidity of aspirated gastric juice was tested for recruited patients with the laboratory pH-meter, and the patients were categorized to have gastric pH values < 4 or ≥ 4. Aspirated gastric juice was also tested to determine the degree of occult bleeding. Among 740 gastric pH tested during patients' follow-up, 26.5% were less than 4. Acute Physiology and Chronic Health Evaluation (APACHE) score, all major risk factors of GI bleeding, chronic organ insufficiency, multiple trauma, number of major and minor risk factors, and current occult bleeding were factors which could predict pH < 4 in our population. Intravenous pantoprazole had also significantly effect on pH > 4 compared with other administered SUP medications. It seems that measurement of gastric pH in high-risk patients for GI bleeding, and paying more attention to the variables related to gastric acidity, is a scientific practical method for rational prescription of more potent acid-suppressing medications to protect gastric mucosa, and prevent overt bleeding in vulnerable population.