Introduction: Mortality from trauma remains a major challenge despite recent substantial improvements in acute trauma care. In trauma care patient resuscitation to correct hypotension from volume loss still majorly relies on use of physiological parameters such as blood pressure, pulse rate, respiratory rate, urine output and oxygen saturation. In resource limited settings these methods may not be sufficient to detect occult tissue hypoxia and the accompanying metabolic derangements.

Methods: A prospective observational study carried out at a level I urban Trauma centre; Accident and Emergency unit. Major trauma patients were consecutively recruited into the study. Venous blood samples were drawn for analysis of serum electrolytes, serum PH and anion gap. The venous blood gas findings were correlated with patients' clinical outcome at two weeks. Ethical approval was obtained.

Results: Ninety three major trauma patients were recruited, patients' age ranged from 12 months to 50 years. Forty nine patients (53%) were acidotic (PH less than 7.32), 39 patients (42%) had low bicarbonate (bicarbonate level less than 21 mmol), 54 patients (58%) had high corrected anion gap (anion gap corrected of 16 or more). Fourteen patients (15%) developed secondary organ failure and 32 (34%) patients died.

Conclusion: Metabolic acidosis is common among major trauma patients, its severity may be related to delay in initiating care. Acid base derangements were predictors of mortality among major trauma patients in this resource limited setting.