Abstract

SHOCK INDEX AND SEQUENTIAL ORGAN FAILURE ASSESMENT SCORE AS PREDICTORS OF OUTCOME IN PATIENTS WITH SEPSIS - A COHORT STUDY

Dr. Parimal Patel MD, DrNB* and Dr. Manoj Singh MD, FNB

ABSTRACT

Sepsis is characterized by the cardinal signs of inflammation (vasodilation, leukocyte accumulation, increased microvascular permeability) occurring in tissues that are remote from the infection. According to the 2003 consensus definition, sepsis is the presence of an infection along with 2 or more of these physiological markers of the systemic inflammatory response syndrome (SIRS): Temperature more than 38.3 degrees Celsius or less than 36 degrees Celsius, heart rate greater than 90 beats per minute, respiratory rate greater than 20 breaths per minute, white blood cell count greater than 12,000 micro/L or less than 4,000 micro/L or greater than 10% immature white blood cell forms. According to Sepsis-3 that was announced at the 45thCritical Care Congress 2016 sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Pathophysiology of sepsis is complex and multifactorial and dependent on characteristics of both the host (co-morbidities and immunosuppression) and the pathogen (virulence and organism load). Endothelial damage leads to coagulation abnormalities, such as intravascular coagulation, fibrinolysis, microvascular thrombi, and impaired tissue oxygenation. Vasodilation and hypotension lead to tissue hypoperfusion and decreased tissue oxygenation leading to organ failure. In contrast to Western countries where Gram- negative sepsis is the predominant cause of sepsis, tropical infections like dengue, malaria, leptospirosis, enteric fever and tuberculosis are also important causes of severe sepsis/ septic shock in India with reported mortality of severe sepsis is over 50%. Scoring of sepsis patients has been often used for individual patient or group prediction and for evaluating and comparing the performance of treatment given like Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) score. APACHE II and the SAPS II (simplified acute physiology score II) are commonly used scoring system for severity of illness in intensive care. SOFA score is related to organ failure and used for prediction of outcome which uses the severity of organ dysfunction in terms of numbers of six organ system of body including Liver, lungs, coagulatory, CVS, renal, and neurologic (each 1-4) to offer a final score [6-24 (maximum)]. SOFA score is calculated at the time of admission and subsequently every 24 hours till discharge. The shock index (SI) is a simple tool calculated by dividing heart rate (HR) by systolic blood pressure (SBP) and the modified shock index (MSI) is calculated by dividing HR over mean arterial pressure (MAP). Two ED Observational Studies assessed the SI for suspected septic patients that gave promising result as a predictor of mortality. Also MAP is the recommended indicator to be followed for deciding fluid resuscitations and vasopressors titration as it is believed to be a better marker for organs perfusion than SBP or DBP alone. We conducted the present study in Indian population to study the disease spectrum with suspected sepsis and assess the usefulness of shock index and SOFA Score on arrival and at 48 hours in predicting the clinical outcome.

Keywords: Vasodilation and hypotension lead to tissue hypoperfusion and decreased tissue oxygenation leading to organ failure.