Dose response to nitric oxide in adult cardiac surgery patients

Hemodynamic effects of inhaled nitric oxide and phosphodiesterase inhibitor (dipyridamole) on secondary pulmonary hypertension following heart valve surgery in adults

“…The potential benefits of iNO in the clinical setting of hypoxemic respiratory failure and the management of secondary PH in cardiac surgery were reported in the English literature since the early 1990s and extensively throughout the last decade [4,[7][8][9]12,13,[17][18][19][20][21][22][23]. Among different possible acting mechanisms, it was also considered that an initial exogenous dose of iNO might compensate for the demonstrated diminished expression of endothelial NO activity of pulmonary vessels in patients with PH [2], as also shown by the decreased level of exhaled NO particularly after cardiopulmonary bypass [24].…”

“…In clinical practice, inhaled nitric oxide (iNO) has been utilized as a selective pulmonary vasodilator in patients undergoing cardiac operation with evidence of secondary PH [1,[7][8][9]. Responsiveness to iNO therapy however appeared to be quite variable, with some patients having limited or transient hemodynamic improvement.…”

“…The possibility to increase cGMP production by iNO and to reduce its breakdown by PDE5 inhibitors (zaprinast, dipyridamole) has been tested in animal and clinical trials in the past [1,[6][7][8][9][10][11]. Data from clinical studies however showed often significant limitations in view of the small number of patients enrolled and of the definition of PH.…”

Pulmonary Hypertension and Thoracic Surgery: Diagnostics and Advances in Therapy and Intraoperative Management

“…Because of this selectivity, it reduces shunting by improving V/Q matching and oxygenation. Dosing may range from 5 to 40 ppm, although one study showed a ceiling effect at 10 ppm [18]. While inhaled NO is approved by the FDA only for use in neonates with hypoxic respiratory failure associated with PH, many centers extensively utilize nitric oxide as inpatient treatment for adult PH patients.…”

A Pathophysiological Approach to Understanding Pulmonary Hypertension in Cardiac Surgery

“…In this context, patients can benefit from PH-specific medical therapy (Table 2) and prophylactic treatments for PH use in cardiac surgery, which will be discussed later in this chapter. In 62 patients with preoperative PH (PVR > 125 dyn·sec·cm -5 immediately before induction of anesthesia) Solina et al (Solina et al, 2001) explored the dose-responsiveness of 10, 20, 30 and 40 ppm of iNO administered upon termination of CPB in comparison to an intravenous bolus of 50 mg/kg of milrinone given 15 minutes before separation from CPB followed by a 0.5 mg/kg/min regimen administered in the operating room thereafter. Treatment with iNO was associated with significant reductions in PVR at all doses but no improved benefit was observed for doses higher than 10 ppm.…”