Faculty Bibliography

Anesthesiologists are uniquely positioned to facilitate emergent care of patients with sepsis in the perioperative setting. A subset of sepsis patients presents with surgical pathology. Emphasis is on timely intervention with source control, antibiotic therapy, and aggressive resuscitation. Ileus, aspiration, and cardiovascular collapse must be considered when inducing patients with sepsis. Dynamic fluid responsiveness may prove an effective tool in minimizing over-resuscitation. Assessment of circulatory failure and drug therapy involves an understanding of preload, afterload, and contractility. Timely, targeted resuscitation and early source control have persisted and remain fundamental to sepsis care.

PURPOSE OF REVIEW/OBJECTIVE:Sepsis-3 guidelines have implications in a deeper understanding of the biopathology of the disease. Further, the review focuses on timely topics and new literature on fluid resuscitation, the value of steroids in sepsis, and new therapeutic options such as angiotensin II, vitamin C, and thiamine as well as the emerging role of procalcitonin (PCT) in managing antibiotics. RECENT FINDINGS/RESULTS:Traditional therapies such as type of crystalloid fluid administration and steroid therapy for sepsis are currently under re-evaluation. Angiotensin II is investigated for reversing vasodilatory shock. The role of capillary endothelium leak and cellular metabolism can be affected by vitamin C and thiamine levels. Biomarker level trends, specifically PCT, can aid clinical suspicion of infection. SUMMARY/CONCLUSIONS:Sepsis-3 shifts the focus from a noninfectious inflammatory process and an emphasis on a dysregulated host response to infection. Hyperchloremic crystalloid resuscitation is associated with poor clinical outcomes. Steroid administration can reverse shock physiology; however, mortality benefits remain uncertain. Angiotensin II, vitamin C, and thiamine are novel treatment options that need further validation. PCT assays can help discern between infectious and noninfectious inflammation.

Humanized mice are a state-of-the-art tool used to study several diseases, helping to close the gap between mice and human immunology. This review focuses on the potential obstacles in the analysis of immune system performance between humans and humanized mice in the context of severe acute inflammation as seen in sepsis or other critical care illnesses. The extent to which the reconstituted human immune system in mice adequately compares to the performance of the human immune system in human hosts is still an evolving question. Although certain viral and protozoan infections can be replicated in humanized mice, whether a highly complex and dynamic systemic inflammation like sepsis can be accurately represented by current humanized mouse models in a clinically translatable manner is unclear. Humanized mice are xenotransplant animals in the most general terms. Several organs (e.g., bone marrow mesenchymal cells, endothelium) cannot interact with the grafted human leukocytes effectively due to species specificity. Also the interaction between mice gut flora and the human immune system may be paradoxical. Often, grafting is performed utilizing an identical batch of stem cells in highly inbred animals which fails to account for human heterogeneity. Limiting factors include the substantial cost and restricting supply of animals. Finally, humanized mice offer an opportunity to gain knowledge of human-like conditions, requiring careful data interpretation just as in nonhumanized animals.