A nurse is reviewing the laboratory results of a client who is postoperative. Which of the following laboratory findings should the nurse identify as an indication of a postoperative infection? Select All that Apply.

Choice A rationale An elevated erythrocyte sedimentation rate, or ESR, is a non-specific marker of inflammation and infection in the body. Normal ESR ranges for males are typically 0 to 15 mm/hr and for females 0 to 20 mm/hr. In a postoperative client, a significantly high ESR suggests that the body is mounting an inflammatory response, which is often triggered by a bacterial or viral infection. Choice B rationale Increased band neutrophils, often referred to as a left shift, indicate that the bone marrow is releasing immature white blood cells to fight an active infection. Normal band neutrophil counts are typically 3 percent to 5 percent of the total white blood cell count. A level above this indicates that the body's primary defenses are being overwhelmed by a pathogen, necessitating a rapid response. Choice C rationale A negative leukocyte esterase in the urine is a normal finding and indicates the absence of white blood cells in the urinary tract. Normal urine should not contain leukocyte esterase. Since a negative result means there is likely no urinary tract infection, it would not be an indicator of a postoperative infection. This finding suggests the urinary system is currently clear of inflammatory markers. Choice D rationale The absence of ketones in the urine is a normal physiological finding. Ketones are produced when the body breaks down fat for energy instead of glucose. Normal urine ketone levels are negative. Their absence does not provide information regarding the presence or absence of an infectious process. Ketonuria is more commonly associated with diabetic ketoacidosis, starvation, or metabolic disturbances rather than infection. Choice E rationale Increased hemoglobin is not typically a sign of infection. Normal hemoglobin ranges are 14 to 18 g/dL for men and 12 to 16 g/dL for women. High hemoglobin levels usually indicate dehydration, polycythemia, or chronic lung disease. In an infection, hemoglobin might actually decrease if the illness is chronic or leads to anemia of inflammation, but an increase is not a diagnostic marker.