Serum Rennin Kinetics Versus Serum Lactate Kinetics as Predictors of Mortality in Septic Shock Patients

Resuscitation in the ICU was traditionally based on blood pressure (1, 2). An assumption that adequate tissue perfusion cannot be made at pressures of 65 mm Hg, and the number itself has been challenged in other investigations (1, 3, 4). Lactate has long been regarded as an adequate indicator of tissue perfusion and prognosis. Most critical care resuscitation are guided by serial lactate levels as a mean to understand the flow and perfusion side of resuscitative aims (2, 5). Not all high lactate levels are indicators of poor tissue perfusion (6).In 2017, Khanna et al (7) reinvigorated the interest in the renin-angiotensin-aldosterone system (RAAS) as a significant biochemical hormonal axis and feedback mechanism in vasodilatory shock after they published the results of the Angiotensin II in High Output Shock Trial. Gleeson et al (8) showed in 2018 that renin appeared to be a much stronger and significant predictor of ICU mortality compared with lactate in a heterogenous shock population Jeyaraju et al (9) reported that renin kinetics are superior to lactate kinetics for predicting in-hospital mortality in critically ill patients with hypotension, with most being vasodilatory shock (most common diagnosis sepsis, also vasoplegia, acute respiratory distress syndrome [ARDS], liver failure) and those who had hypotension more than 6 hours while of vasopressors included. The bottom line in the previous investigations is that renin was a better marker of poor outcomes in comparison with concurrently measured lactate levels in critically ill ICU patients.

adult patients aged 18 years or older who were diagnosed with septic shock according to the Third International Consensus Definitions for Sepsis and Septic Shock.[1] In septic shock, patients' blood lactate levels were found to be more than 2 mmol/L even after receiving enough fluids, and patients' mean arterial pressure (MAP) had to be maintained at 65 mmHg or above with the use of vasopressor medication.Before enrollment, all patients or their authorized representatives were asked to provide written informed consent.

Patients were excluded if they had acute coronary syndrome, chronic treatment with angiotensin receptor blockers (ARBs) or ACE inhibitors (ACEIs), a do-not-resuscitate (DNR) order, chronic kidney disease stage IV or V (baseline estimated glomerular filtration rate <30 mL/min/1.73 m²), or if they passed away within the first 24 hours of being admitted to the intensive care unit (ICU).