Sildenafil protocol: cardiac catheterization lab

Sildenafil Protocol: The Efficacy of Oral Sildenafil (Viagra) in Childhood and
Neonatal Pulmonary Hypertension
Principal Investigators: Dr. Ian Adatia and Dr. Tilman Humpl Co-Investigators: Janette Reyes (CNS/NP), Dr. Desmond Bohn Dr. Helen Holtby, Winnie Seto (Pharm.D), Derek Stephens CARDIAC CATHETERIZATION LAB PROTOCOL
Pre-Cardiac Catheterization Preparation: In addition to the Cardiac Clinic’s pre-cardiac catheterization process, the following will be initiated: 1. Consent for the use of sildenafil and participation into the study will be obtained 2. Discuss process of the study and address the patient’s and family’s inquiries. 3. For a child greater that 4 years of age will complete a colour vision test, using HRR Pseudoisochromatic Plates. Assessment by Janette Reyes. 4. A written order for Sildenafil and Flolan will be completed by the fellow. 5. The fellow will arrange with the Respiratory Therapist in the Critical Care Unit, the delivery of nitric oxide, for use as per study protocol, during the cardiac Cardiac Catheterization Procedure: 1. Obtain consent for sildenafil testing at the pre-cardiac catheterization 2. All patients will receive a standard general anesthetic, endotracheal intubation and mechanical ventilation to achieve normal arterial pH and PCO2 without the use of volatile or intravenous anaesthetic agents known to cause pulmonary vasodilation or constriction. Midazolam and propofol will be avoided. A
nasogastric tube will be placed for the administration of sildenafil. 3. Measurement of baseline haemodynamics, arterial and venous saturations, blood gases, and plasma cGMP level. (Standard techniques will be used to measure right and left sided heart and vascular pressures, systemic and pulmonary blood flow and resistance will be estimated by Fick with measured oxygen consumption or thermodilution if appropriate, intrapulmonary shunt fraction will be estimated from the method of Cournand and Riley). 4. 100% oxygen for 15 minutes with haemodynamic measurements, arterial and 5. NO gas by inhalation at 40 ppm for 15 minutes with haemodynamic measurements, arterial and venous saturations, blood gases, and plasma cGMP level. 6. Return to baseline #2 (15 minutes after discontinuing NO) haemodynamic measurements, arterial and venous saturations, blood gases, and plasma cGMP 7. Sildenafil 0.25mg/kg by nasogastric tube. 8. Repeat haemodynamic measurements, arterial and venous saturations, blood gases, and plasma cGMP level with sildenafil level 20-30 minutes later. 9. If less than 10% fall in pulmonary artery pressure or PVRI, without systemic hypotension, repeat sildenafil dose of 0.25 mg/kg. 10. Repeat haemodynamic measurements, arterial and venous saturations, blood gases, and plasma cGMP level with sildenafil level after 20-30 minutes. 11. Add inhaled NO at 40 ppm for 15 minutes haemodynamic measurements, arterial and venous saturations, blood gases, and plasma cGMP level. 12. Discontinue NO, 15 minutes later repeat haemodynamic measurements, arterial and venous saturations, blood gases, and plasma cGMP level with cAMP. 13. Administer 300mcg aerosolized prostacyclin (Flolan) after 30 minutes repeat haemodynamic measurements, arterial and venous saturations, blood gases, and plasma cGMP, cAMP, sildenafil level. 14. Patients with an intravenous line will have blood sampled from sildenafil levels at 6 & 8 hours post dosing in the recovery area. These samples will be omitted if blood can not be withdrawn from the existing line or the line is removed. 1. Once the final calculations have been completed, finalized, and signed by the staff physician, they will be reviewed by Dr. Humpl. 2. Follow-up plans will be discussed with the family and arranged by Janette Reyes. 3. If the patient is to start sildenafil therapy, a written script must be signed by Dr. Humpl. The patient and family will be instructed to pick up the medication at
HSC’s Central Pharmacy only, and not at Shopper’s Drug Mart.

Source: http://www.sickkids.ca/pdfs/Cardiology/7724-SildenafilCathLabProtocol.pdf