Q: 52 year old male is given 30 mg of protamine sulfate to reverse heparin effect for immediate post-op bleeding in ICU. Patient has pulmonary Artery Catheter in place. Patient pulmonary artery pressure suddenly jumped from 36/22 to 80/39. CVP rised to 22 and patient became hypotensive. Beside slowing infusion of Protamine, what would be the best management strategy?

Answer: Start inhaled Prostacyclin or inhaled Nitric Oxide

Acute pulmonary hypertension is well known complication of Protamine Sulfate. It may require treatment for right or biventricular function with use of pressors and inotropes. Use of inhaled prostacyclin may have instant effect in improving pulmonary hypertension and resulting hemodynamic collapse.

Various risk factors are described for "protamine reactions" include existing pulmonary hypertension, allergy to vertebrate fish, vasectomized men, and previous protamine exposure, particularly among diabetics using protamine-linked insulin. 

Reducing thromboxane formation by inhibiting cyclooxygenase using aspirin or other nonsteroidal drugs has been shown in some studies to provide some protection from protamine induced hypertension.

Inhaled Nitric Oxide is another alternative but it is not readily available in many centers. Also, it is not cost effective in comparison to inhaled Prostacyclin.

Reference:

Jerath, Angela FANZCA; Srinivas, Coimbatore FRCA; Vegas, Annette FRCPC; Brister, Stephanie FRCSC - The Successful Management of Severe Protamine-Induced Pulmonary Hypertension Using Inhaled Prostacyclin - Anesthesia & Analgesia: February 2010 - Volume 110 - Issue 2 - pp 365-369