What is the best next step in managing a 2-hour-old boy with meconium aspiration syndrome, hypotension, tachycardia, tachypnea, and decreased oxygen saturation, confirmed by chest x-ray and echocardiogram showing decreased right ventricular output?

From the Guidelines

The best next step in management of this patient is nitric oxide (option D). This 2-hour-old newborn is presenting with persistent pulmonary hypertension of the newborn (PPHN) secondary to meconium aspiration syndrome. The evidence for PPHN includes the pre-ductal/post-ductal oxygen saturation difference (90% in right hand vs 79% in right foot), severe respiratory distress requiring intubation, and echocardiogram showing decreased right ventricular output. Inhaled nitric oxide is the treatment of choice for PPHN as it selectively dilates the pulmonary vasculature, reducing pulmonary vascular resistance and improving oxygenation, as supported by the American Heart Association and American Thoracic Society guidelines 1.

The pathophysiology of PPHN involves increased pulmonary vascular resistance, right-to-left shunting, and severe hypoxemia, which can be addressed by inhaled nitric oxide, as explained in the ACCF/AHA 2009 expert consensus document on pulmonary hypertension 1. The use of inhaled nitric oxide has been demonstrated to improve oxygenation and reduce the need for extracorporeal membrane oxygenation in neonates with PPHN, as shown in multi-center randomized clinical trials 1.

Other key aspects of management include:

• Maintaining adequate oxygenation, with a goal of maintaining systemic oxygen saturation between 90 and 95% to reduce pulmonary artery hypertension and right ventricular workload, as recommended by the American Journal of Respiratory and Critical Care Medicine 1
• Ventilation, with the potential use of high-frequency ventilation to facilitate lung recruitment and enhance the efficacy of inhaled nitric oxide
• Blood pressure support, with the goal of maintaining normal levels for age to reduce both left and right ventricular dysfunction and enhance systemic oxygen transport, as recommended by the American Heart Association and American Thoracic Society guidelines 1
• Treatment of the underlying meconium aspiration syndrome, which may involve surfactant therapy and other supportive measures.

The other medication options, such as albuterol, hydrochlorothiazide, ibuprofen, and vecuronium, would not address the primary pathophysiology of pulmonary hypertension in this critically ill neonate.

From the FDA Drug Label

INOmax® is indicated to improve oxygenation and reduce the need for extracorporeal membrane oxygenation in term and near-term (>34 weeks gestation) neonates with hypoxic respiratory failure associated with clinical or echocardiographic evidence of pulmonary hypertension in conjunction with ventilatory support and other appropriate agents.

The best next step in management of this patient is D. Nitric oxide.

• The patient is a term neonate with hypoxic respiratory failure and evidence of pulmonary hypertension, which are indications for the use of nitric oxide.
• The patient's condition, meconium aspiration syndrome, is one of the etiologies studied in the clinical trials of nitric oxide, as seen in the NINOS study 2.
• The use of nitric oxide in this patient may improve oxygenation and reduce the need for extracorporeal membrane oxygenation.

From the Research

Patient Management

The patient is a 2-hour-old boy with severe respiratory distress, meconium aspiration syndrome, and decreased right ventricular output. The best next step in management would be to address the pulmonary hypertension and improve oxygenation.

Treatment Options

• The use of nitric oxide has been shown to be effective in treating pulmonary hypertension and improving oxygenation in newborns 3, 4.
• Inhaled nitric oxide acts as a selective pulmonary vasodilator and has been approved by the FDA for the treatment of persistent pulmonary hypertension of the newborn 3.
• Studies have demonstrated that inhaled nitric oxide can decrease pulmonary artery pressure and improve oxygenation in hypoxic newborns 3, 4.

Recommended Course of Action

• Based on the evidence, the best next step in management of this patient would be to administer Nitric oxide (D) to address the pulmonary hypertension and improve oxygenation.
• The other options, Albuterol (A), Hydrochlorothiazide (B), Ibuprofen (C), and Vecuronium (E), are not directly relevant to the treatment of pulmonary hypertension and meconium aspiration syndrome in this patient.