Gastrointestinal Dysfunction in Critically Ill Patients With Traumatic Brain Injury: Clinical Implications and Putative Mechanisms: a Narrative Review.

PURPOSE OF THE REVIEW: Moderate to severe traumatic brain injury (TBI) requiring intensive care is associated with high morbidity, mortality and long-term disability. In addition to neurologic sequelae, TBI causes a systemic disease with associated injury to other organ systems, including the gastrointestinal (GI) tract. Here, we review the evidence that GI tract dysfunction occurs after TBI and discuss the clinical implications of GI tract dysfunction on the clinical care of TBI patients, including inadequate nutritional support, elevated risk of pneumonia, and a hyperactive inflammatory response.

RECENT FINDINGS: We highlight recent findings that highlight putative mechanisms through which GI tract pathology may arise after TBI, including vagal nerve and enteric nervous system dysfunction, gut microbiome dysbiosis, sympathetic hyperactivity and iatrogenic injury. Finally, we highlight future approaches to target the GI tract that could improve outcomes in this critically ill patient population. In summary, we review the evidence supporting a role for GI tract dysfunction in the pathophysiology of critically ill TBI patients and highlight potential mechanisms through which GI tract dysfunction may worsen outcomes in this population.