The pediatric cardiology pharmacopeia: 2013 update.

The use of medications plays a pivotal role in the management of children with heart diseases. Most children with increased pulmonary blood flow require chronic use of anticongestive heart failure medications until more definitive interventional or surgical procedures are performed. The use of such medications, particularly inotropic agents and diuretics, is even more amplified during the postoperative period. Currently, children are undergoing surgical intervention at an ever younger age with excellent results aided by advanced anesthetic and postoperative care. The most significant of these advanced measures includes invasive and noninvasive monitoring as well as a wide array of pharmacologic agents. This review update provides a medication guide for medical practitioners involved in care of children with heart diseases.

What leads to different mediators of alkalosis-induced vasodilation in isolated and in situ pulmonary vessels?

We previously found that nitric oxide synthase (NOS) inhibition fully blocked alkalosis-induced relaxation of piglet pulmonary artery and vein rings. In contrast, NOS inhibition alone had no effect on alkalosis-induced pulmonary vasodilation in isolated piglet lungs. This study sought to identify factors contributing to the discordance between isolated and in situ pulmonary vessels. The roles of pressor stimulus (hypoxia vs. the thromboxane mimetic U-46619), perfusate composition (blood vs. physiological salt solution), and flow were assessed. Effects of NOS inhibition on alkalosis-induced dilation were also directly compared in 150-350-microm-diameter cannulated arteries and 150-900-microm-diameter, angiographically visualized, in situ arteries. Finally, effects of NOS inhibition on alkalosis-induced vasodilation were measured in intact piglets. NOS inhibition with N(omega)-nitro-L-arginine fully abolished alkalosis-induced vasodilation in all cannulated arteries but failed to alter alkalosis-induced vasodilation in intact lungs. The results indicate that investigation of other factors, such as perivascular tissue (e.g., adventitia and parenchyma) and remote signaling pathways, will need to be carried out to reconcile this discordance between isolated and in situ arteries.