Serum lactate and mean arterial pressure thresholds in patients with cirrhosis and septic shock

The Sepsis-3 guidelines have incorporated serum lactate levels of >2 mmol/L in septic shock definition to account for higher observed mortality. Further evidence is needed to support this threshold in cirrhosis, as well as target mean arterial pressure (MAP) during resuscitation.

This observational cohort study investigated the association between initial serum lactate and resuscitation MAP levels on in-hospital mortality in patients with and without cirrhosis. Patients admitted to the intensive care unit for the treatment of septic shock between 2006 and 2021 in a quaternary academic center were included. Patients with cirrhosis documented on imaging and International Classification of Disease codes (n=595) were compared to patients without cirrhosis (n=575). The association of intensive care unit admission lactate levels and median 2-hour MAP with in-hospital mortality and the need for continuous renal replacement therapy was assessed. The association between median 24-hour MAP and in-hospital mortality was analyzed post hoc.

Within the cirrhosis group, admission lactate levels of 2-4 and >4 mmol/L were associated with increased in-hospital mortality compared to lactate <2 mmol/L [adjusted odds ratio (aOR): 1.69, CI: 1.03-2.81, aOR: 4.02, CI: 2.53-6.52]. Median 24-hour MAP 60-65 and <60 mm Hg were also associated with increased in-hospital mortality compared with MAP >65 mm Hg (aOR: 2.84, CI: 1.64-4.92 and aOR: 7.34, CI: 3.17-18.76). In the noncirrhosis group, associations with in-hospital mortality were weaker for lactate 2-4 and >4 mmol/L (aOR: 1.32, CI: 0.77-2.27 and aOR: 2.25, CI: 1.40-3.67) and median 24-hour MAP 60-65 and <60 mm Hg (aOR: 1.70, CI: 0.65-4.14 and aOR: 4.41, CI: 0.79-29.38).

These findings support utilizing lactate >2 mmol/L in the definition of septic shock, as well as a target MAP of >65 mm Hg during resuscitation in patients with cirrhosis.