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Background: The immune response to subsequent stressors after traumatic hemorrhage and resuscitation (HR) may be dependent on timing and counterin-flammatory cytokine expression. Our hypothesis was that the timing of the second hit would influence the immune response, and we investigated whether an early second stimulus after HR would result in worse acute lung injury. Methods: One hour after HR or sham shock (Sham), mice were given intraperitoneal (IP) injections of lipopolysaccharide (LPS) or saline (Sal). Mortality, pulmonary function (PF), bronchoalveolar lavage neutrophil infiltration, and bronchoalveolar lavage (BAL), in addition to serum interleukin (IL)-10, IL-6, and tumor necrosis factor-a (TNF-a), were assessed. Results: HR blunted serum TNF-a expression to LPS (HR+LPS, 424.8 pg/ mL; Sham+LPS, 2,248.8 pg/mL; p < 0.05), but primed for increased bronchoalveolar lavage TNF-α (HR+LPS, 259.5 pg/ mL; Sham+LPS, 23.5 pg/mL; p < 0.05). Elevated serum TNF-α corresponded with greater bronchoalveolar lavage neutrophil infiltration (HR+LPS, 0.93%; Sham+LPS, 17.5%; p < 0.05). IL-10 expression was similar in HR and Sham. There were no significant differences in mortality or PF between HR+LPS and Sham+LPS. Conclusion: Priming and blunting of the LPS-induced TNF-a response occurred concomitantly in two-hit mice, corresponding to an altered pattern of pulmonary inflammation, but no change in PF.

Background. The “July phenomenon,” a common belief in medical academia, refers to purported errors, inefficiency, and negative outcomes during the summertime transition of the house staff. We hypothesized that care in a trauma service is consistent throughout the year and that the July phenomenon therefore is a myth. Methods. The records of adults admitted to a trauma service between July 1994 and September 1999 were evaluated. The care of and outcomes for patients admitted in July and August were compared with those of patients admitted in April and May. Results. Nine hundred seventeen patients were evaluated over 5 years. Patients were well matched by the Injury Severity Score, the Glasgow Coma Score, by mechanism, and by survival probability. Patients admitted in the spring were significantly older, by a mean of 5.1 years. Length of stay and intensive care unit stay were similar. Emergency department times were similar, as were resuscitation times, infection rates, and hospital costs. The mortality of patients was similar between the 2 times. Conclusions. There was no evidence of an increase in negative outcomes early in the academic year compared with the end of the academic year. We believe that a systematic approach to the diagnosis, resuscitation, and treatment of trauma prevented a July phenomenon. (Surgery 2001;130:346-53.)