A 65-year-old man undergoes a low anterior resection for rectal cancer. On the fifth day in hospital, his physical examination shows a temperature of 39degC (102degF), blood pressure of 150/90 mm Hg, pulse of 110 beats per minute and regular, and respiratory rate of 28 breaths per minute. A computed tomography (CT) scan of the abdomen reveals an abscess in the pelvis. Which of the following most accurately describes his present condition?: (A) Systemic inflammatory response syndrome (SIRS), (B) Sepsis, (C) Severe sepsis, (D) Septic shock
Answer is B. The correct diagnosis is sepsis. Systemic inflammatory response syndrome (SIRS) involves 2 or more of the following: temperature >38degC (100degF) or 90 beats per minute, respiratory rate >20 or PaCO2 12,000 or 10% immature neutrophils. Sepsis = SIRS + documented infection. Severe sepsis = sepsis + organ dysfunction or hypoperfusion (lactic acidosis, oliguria, or altered mental status). Septic shock = sepsis + organ dysfunction + hypotension (systolic blood pressure 90 mm Hg with vasopressors).