Sunday, March 23, 2014

Lost Without a MAP: Blood Pressure Targets in Septic Shock

Another of the critical care articles published early online at last week was this trial of High versus Low Blood-Pressure Target in Patients with Septic Shock.  In this multicenter, open-label trial, the authors enrolled 776 patients in France and randomized them to a target MAP (mean arterial pressure) of 65-70 mm Hg (low target) versus 80-85 (high target).  The hypothesis is that a higher pressure, achieved through vasopressor administration, will improve 28-day mortality.  If you don't already know the result, guess if the data from this trial support or confirm the hypothesis (the trial had 80% power to show a 10% absolute reduction in mortality).

Thursday, March 20, 2014

Sepsis Bungles: The Lessons of Early Goal Directed Therapy

On March 18th, the NEJM published early online three original trials of therapies for the critically ill that will serve as fodder for several posts.  Here, I focus on the ProCESS trial of protocol guided therapy for early septic shock.  This trial is in essence a multicenter version of the landmark 2001 trial of Early Goal Directed Therapy (EGDT) for severe sepsis by Rivers et al.  That trial showed a stunning 16% absolute reduction in mortality in sepsis attributed to the use of a protocol based on physiological goals for hemodynamic management.  That absolute reduction in mortality is perhaps the largest for any therapy in critical care medicine.  If such a reduction were confirmed, it would make EGDT the single most important therapy in the field.  If such reduction cannot be confirmed, there are several reasons why the Rivers results may have been misleading:

There were other concerns about the Rivers study and how it was later incorporated into practice, but I won't belabor them here.  The ProCESS trial randomized about 1350 patients among three groups, one simulating the original Rivers protocol, one to a modified Rivers protocol, and one representing "standard care" that is, care directed by the treating physician without a protocol.  The study had 80% power to demonstrate a mortality reduction of 6-7%.  Before you read further, please wager, will the trial show any statistically significant differences in outcome that favor EGDT or protocolized care?