SEPSIS AND SEPTIC COMPLICATIONS IN THE SURGICAL PATIENT - WHO IS AT RISK

The estimation of patients who are at risk for infection, sepsis, and organ dysfunction/failure is crucial not only for inclusion in treatme nt algorithms but also for entry into appropriate clinical trials of p rophylaxis and therapy. Patients on the surgical service who have sust ained major trauma or who have undergone transplantation are clearly a t the greatest risk. Other immunosuppressed patients at risk for sepsi s include those receiving myelosuppressive chemotherapy, those with ov erwhelming malignancy and those who suffer from cirrhosis, diabetes me llitus, and severe malnutrition, We have focused on the trauma patient , in whom infection and organ failure are the leading causes of late d eath, major morbidity, and prolonged hospital stay. Over a 10 yr perio d, we have surveyed a number of host defense parameters that pertain t o an adequate immune response and found a suppressed response shortly after injury in many. All were anergic to a standard skin test panel, and the duration of anergy varied with the clinical course of infectio n. Immunoglobulin levels were low after major injury as well as specif ic antibodies to both Gram-positive and Gram-negative organisms. The a bility of serum from the trauma patient to opsonize heat-killed bacter ia was markedly depressed 24 h after injury in those patients who subs equently died of infection. Class II major histocompatibility antigen expression on peripheral blood monocytes correlated closely with clini cal outcome and led to the development of an Outcome Predictive Score. This score can identify patients within hours of hospitalization who are at risk of subsequently developing overt clinical infection and se psis. Intervention then can be applied to such at-risk populations pri or to the onset of sepsis and to evaluate the efficacy of prophylaxis. Patients in whom prophylaxis fails could be eligible for trials of th erapeutic intervention as well.