Nitric Oxide to Treat Pulmonary Embolism

This is a randomized, double blind study to treat subjects diagnosed with pulmonary embolism with inhaled nitrix oxide. In this clinical trial investigators will randomized patients to receive inhaled nitric oxide or sham (nitrogen + oxygen) for 24 hours. Patients must have a submassive pulmonary embolism (PE) and evidence of right ventricular (RV) heart dysfunction. Investigators hypothesize that the administration of inhaled NO + oxygen to patients with severe submassive PE will improve RV function, reduce RV strain and necrosis and improve dyspnea (difficulty breathing) more than sham oxygen treatment.

Inclusion criteria

• Age >/= 18
• Pulmonary imaging-proven PE, as interpreted by local radiologist
• At least one predictor of RV dysfunction:

• echocardiography with RV dilation or hypokinesis,
• estimated RVSP >40mm HG,
• RV>LV on CTPA,
• elevated troponin I (>0.1 ng/mL) or natriuretic peptide (BNP > 90 pg/mL),
• screening bedside cardiac ultrasound with color flow capability that shows RV dysfunction,
• RV strain on ECG
• Plan to admit to a bed with telemetry capability

Exclusion criteria

• Vasopressor support at time of enrollment
• Pregnancy
• Plan by clinical care team to use lytic or surgical embolectomy
• Plan by clinical team to use platelet inhibiting drugs
• Contraindication to anticoagulation
• Altered mental status such that the patient is unable to provide informed consent
• Inability to use a nasal cannula or face mask
• Comfort care measures instituted
• Supplemental oxygen requirements greater than can be administered via nasal cannula in order to maintain Sa)2 > 80%
• Pneumothorax with decompression
• Serum MetHb > 10%
• Recent use of drugs known to increase cGMP
• Use of nitroprusside or nitroglycerin within the last 4 hours
• Use of any other nitrates with in the past 24 hours
• Use of a fibrinolytic medicine within the past 14 days