Optimal vasopressor sequencing in septic shock with concurrent RV failure?
62M admitted to the ICU with septic shock from a urinary source. Lactate 4.8, MAP 54 despite 30 mL/kg crystalloid. Bedside echo shows a dilated, poorly contracting RV with septal flattening (D-sign) and preserved LV function.
Norepinephrine is up to 0.4 mcg/kg/min. I'm weighing the next agent: vasopressin for its lack of pulmonary vasoconstriction vs. adding an inotrope/inodilator for the failing RV. How are you sequencing pressors here, and where does inhaled pulmonary vasodilation fit before considering mechanical support?
2 Answers
With a failing RV and septal flattening you want to avoid worsening pulmonary vascular resistance while restoring perfusion pressure to the RV coronary bed.
My sequence: keep norepinephrine as the backbone but add vasopressin (0.03 units/min) early — it raises systemic pressure with relatively little pulmonary vasoconstriction, which protects RV afterload. If the RV remains the limiting factor after MAP is restored, add an inodilator (dobutamine or milrinone) cautiously, watching for systemic hypotension, and start inhaled pulmonary vasodilation (iNO or inhaled epoprostenol) to selectively drop PVR. Keep the RV "full but not overfilled" — a passive fluid load here often worsens things. If lactate and echo don't improve on this, escalate to mechanical support rather than chasing ever-higher pressor doses.
Agree with adding vasopressin early. One practical point: get an arterial line and track diastolic BP as a surrogate for RV coronary perfusion — it's often more useful than MAP alone in this scenario. Also worth ruling out a concurrent PE given the acute RV picture.