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Warren Myron (Warren) Zapol, MD

  • Phone: 617-726-3030
Department of Anesthesia, Critical Care and Pain Medicine
Clinical Interests
Critical care
Acute respiratory distress syndrome (ARDS)
Boston: Massachusetts General Hospital
Medical Education
MD, University of Rochester School of Medicine and Dentistry
Residency, Massachusetts General Hospital
Residency, NIH, National Heart, Lung, and Blood Institute
Board Certifications
Anesthesiology, American Board of Anesthesiology
Foreign Languages
Patient Age Group
Accepting New Patients
Accepting New Patients

BiographyDr. Zapol is currently the Director of the MGH Anesthesia Center for Critical Care Research at Massachusetts General Hospital, where he collaborates with many researchers to explore the pulmonary circulation of mammals in normal and disease states. Over the last 20 years, his laboratory has focused upon the physiological and pathophysiological roles of nitric oxide (NO). Based on his lab's pioneering studies, inhaled NO (INO) is now used to treat approximately 30,000 patients per year in the USA to vasodilate the pulmonary circulation and augment arterial oxygenation. For many hypoxic infants and for children after heart surgery, this inhaled therapy is life-saving. In December 1999, the FDA approved INO therapy to treat term newborn infants with hypoxic respiratory failure; this therapy was developed in our lab.

The Zapol lab is presently closely allied with Dr. Kenneth Bloch's laboratory. Together they are focusing on the storage lesion of aged blood cells, and methods for preventing the toxic effects of extracellular hemoglobin that is released by hemolysis in malaria or genetic diseases such as sickle cell anemia. In addition, the Zapol lab is studying how to make the transfusion of heme-based oxygen carriers both safe and effective for transfusion in the field.


Research Areas

Inhaled nitric oxide, stored blood transfusion, cerebral malaria, hemoglobin gas binding

Description of Research

My research is directed at understanding a wide range of critical illnesses that can be therapeutically treated with novel inhaled gases. Inhaled nitric oxide (NO) is a central focus of this laboratory's research, both as a selective pulmonary vasodilator and a safe method for loading the body with NO donor molecules. As a selective pulmonary vasodilator, inhaled NO is used to treat pulmonary hypertension and to improve ventilation-perfusion matching. NO inhalation leads to the formation of circulating NO metabolite which can neutralize oxygen free radicals, activate soluble guanylate cyclase (to make cGMP) and prevent the side effects of excessive scavenging of endogenous NO molecules by transfusion of stored red cells. We also study hemoglobin, discovering small molecules that alter its affinity for gases such as oxygen, carbon monoxide and NO. The prevention and treatment of acute lung injury is also studied in this laboratory with mouse models of ventilator-induced lung injury and transfusion.  My group studies inhaled nitric oxide in children with cerebral malaria and adults with stored blood transfusion. Methods for the economical  in situ manufacture of Nitric Oxide by electrical sparks in air are being explored. Animal models used in the laboratory extend from mice to sheep, with a special focus on translational research to improve the care of critically ill patients

PublicationsView publications

In Generals: 08.10.12

In General awards and honors

Study Should Prove Helpful in Quest for Safer, More Effective Blood Substitutes

A study published in the March 2010 issue of the journal Anesthesiology gives researchers new insights in how to better understand and control a severe side effect of hemoglobin-based oxygen carriers, often referred to as "artificial blood."

Mass. General team generates therapeutic nitric oxide from air with an electric spark

A lightweight, portable system developed by an MGH research team can produce the potentially life-saving gas nitric oxide from the air by means of an electrical spark.

Anesthesia, Critical Care and Pain Medicine
55 Fruit Street
Boston, MA 02114-2696

Phone: 617-726-3030
Fax: 617-726-3032

Anesthesia, Critical Care and Pain Medicine
55 Fruit Street
Boston, MA 02114-2696

Phone: 617-726-3030
Fax: 617-726-3032

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