Quantitative Analysis of Organ Tissue Damage after Septic Shock

Abstract

The objective of this study was to quantify end-organ damage caused by bacteremic sepsis. Twelve adult swine were divided into two groups. The anesthesia control group (n = 6) received general anesthesia for 4 hours. The septic shock group (n = 6) received an infusion of Aeromonas hydrophila under general anesthesia for 4 hours. Swine were sacrificed at the end of the 4-hour procedure. Tissues from lungs, kidneys, livers, and hearts were stained with hematoxylin and eosin. Images of tissues were studied with digital image analysis. In lungs, cytoplasmic area (CA), nuclear area (NA), intra-alveolar hemorrhage (IAH), total airspace (TAS), and alveolar septum thickness (ST) were measured. Nuclear and cytoplasmic intensities (NI and CI) were measured in integrated optical density units (IOD). In kidneys, livers, and hearts, CA, CI, NA, and NI were measured similarly. Sinusoidal blood in the liver and vacuolization (VAC) in the kidney were also measured. In septic lungs, CI, NA, NI, ST, IAH, TAS, and ratios of NA/CA, NI/CI, and IAH/TAS were significantly increased compared with the control ( P < 0.02). In septic kidneys, CI, NA, VAC, NA/CA, and NI/CI were significantly increased ( P < 0.0005). In livers, CA, CI, and NI/CI were significantly increased ( P < 0.005). In hearts, the ratios of NA/CA and NI/CI were statistically significant. End organs from septic swine, with exception of the heart, showed significantly higher levels of cellular damage. Digital image analysis provides an objective, precise, and accurate method of quantifying image characteristics. Automating these tasks is a high priority in the research and clinical community in providing a reproducible method for longitudinal analysis of various biological studies.