INTESTINAL PERMEABILITY CORRELATES WITH SEVERITY OF INJURY IN TRAUMA PATIENTS

Background: Increased intestinal permeability (IP) and the release of toxic intraluminal materials have been implicated in the systemic infl ammatory response syndrome (SIRS) and multiple organ failure (MOF) obs erved in patients after severe trauma. Previous studies of intestinal permeability have failed to demonstrate a correlation between early me asurements of IP and indicators of injury severity. This study examine s the relationship between standard measures of injury severity and th e early (day 1) and delayed (day 4) changes in IF. Associations betwee n IP and the development of SIRS, MOF, and infectious complications we re also studied. Methods: The metabolically inactive markers lactulose (L) and mannitol (M) were used to measure IP in 29 consecutive patien ts who sustained injuries that required admission to the surgical inte nsive care unit and in 10 healthy control subjects, Measurements were made within 24 hours of admission and on hospital day 4, Severity of i njury was assessed by A Severity Characterization of Trauma (ASCOT), T rauma and Injury Severity Score (TRISS), Injury Severity Score (ISS), Revised Trauma Score (RTS), and Acute Physiology and Chronic Health Ev aluation (APACHE) II score. Postinjury infections and parameters of SI RS and MOF were recorded. Results: The IP of healthy volunteers (L/M, 0.025 +/- 0.008) was within the normal range (L/M less than or equal t o 0.03), whereas the average IP in injured patients was increased both within 24 hours (L/M, 0.139 +/- 0.172) and on the fourth hospital day (L/M, 0.346 +/- 0.699), No significant correlation between severity o f injury and increased IP was seen within 24 hours of injury, A signif icant correlation was seen on hospital day 4, however, with all severi ty indices measured (ASCOT: r = 0.93, R-2 = 0.87, p < 0.001; TRISS;: r = 0.93, R-2 = 0.87 p < 0.001; ISS: r = 0.84, R-2 = 0.70, p < 0.001; R TS: r = 0.68, R-2 = 0.47, p = 0.002; APACHE II score: r = 0.51, R-2 = 0.26, p = 0.04), Patients with markedly increased IP (L/M greater than or equal to 0.100) experienced a significant increase in the developm ent of SIRS (83 vs. 44%;p = 0.03) and subsequent infectious complicati ons (58 vs, 13%;p = 0.01) and showed close correlation with the multip le organ dysfunction scores (r = 0.87, R-2 = 0.76, p < 0.001), Conclus ion: These observations demonstrate that the increased IP observed aft er trauma correlates with severity of injury only after 72 to 96 hours and not within the initial 24 hours of injury. A large increase in IP is associated with the development of SIRS, multiple organ dysfunctio n, and an increased incidence of infectious complications.