Objective  

To identify early prognostic markers of septic shock among catheterization-derived hemodynamic and metabolic data.

Design  

Prospective cohort study.

Setting  

A medical intensive care unit in a university hospital.

Patients  

Thirty-two consecutive patients with septic shock, separated into two groups according to shortterm (10-day) evolution: 18 acute survivors and 14 fatalities.

Measurements  

Usual hemodynamic and metabolic variables were measured at the onset of shock, i.e. when the catheter was inserted (T0), and 24 h later (T24). The values collected for each group at T0 and T24 and their 24-h changes were compared.

Results  

On admission, no difference was found between acute survivors and eventual fatalities. After 24 h, fatalities presented with significantly lower mean arterial pressure (p<0.01), left="" ventricular="" stroke="" work="" index="">P<0.05) and="" higher="" lactate="" levels="">p<0.01) than="" acute="" survivors.="" moreover,="" the="" 24-h="" changes="" of="" lactate="" and="" blood="" pressure="" were="" also="" of="" prognostic="" value="">p<0.05). oxygen="" delivery="" and="" oxygen="" consumption="" did="" not="" differ="" statistically="" between="" the="" two="" groups.="" at="" t24,="" a="" mean="" arterial="" pressure="" of="" less="" than="" 85="" mmhg="" and="" a="" lactate="" level="" equal="" to="" or="" greater="" than="" 3.5="" mmol/l="" were="" independently="" associated="" with="" poor="" survival="" (37.5%="" and="" 30.7%,="" respectively).="" day="" 10="" survival="" was="" only="" 12.5%="" when="" both="" criteria="" were="" present="" at="">

Conclusions  

Changes in mean arterial pressure and arterial blood lactate within the first 24 h of treatment are strong prognostic indicators of short-term survival in patients with septic shock. After 24 h of treatment, maintenance of a mean blood pressure equal to or greater than 85 mmHg correlates with survival at day 10. Data suggest that early reductions in both cardiac function and vascular tone play a determining role in the hypotension observed in fatalities. Persistence of hyperlactatemia in hypotensive patients bodes particularly ill. Blood pressure and lactate level are simple bedside parameters that can enable the clinician to identify patients with a high risk of mortality.