Describe Prostaglandin - Availability, Administration and Alternatives ?
Prostaglandin El (available in India as Prostin VR, Pharmacia) is a very essential drug and should be available in every newborn nursery. It can restore ductal patency in most newborns with closing ducts and is therefore life saving in duct dependent situations. Its effect is usually confinned by improving saturations in newborns with duct dependent pulmonary circulation and resolution of the circulatory failure and acidosis in newborns with duct dependent systemic circulation. Its efficacy declines somewhat with increasing age particularly after 15 days and it is usually not effective in opening a closed duct after 30 days. The initial dose of prostaglandin is 0.05-0.1 microgram/kg/minute. Once the duct has, opened up (this can be confirmed by the clinical response or by echocardiography), the dose may be reduced to as low as 0.01 mcg/kg/min. This allows maintenance of ductal patency with minimal adverse effects. Adverse effects of PGEl infusion include apnea, bradycardia, tachycardia, hypotension, fever, gastric distension and seizures. Leukocytosis frequently accoinpanies prostaglandin uses. Administration over several days may result in increased lung and body water from capillary leak, thrombocytopenia, gastric outlet obstruction and cortical hyperostosis.
Prostaglandin is available in most cities in India. Newborn nurseries should endeavor to obtain one or two ampoules of the drug and this should be stored in the refrigerator and replaced when consumed. The drug is expensive (- Rs, 10,000). It is, however, possible to extend the use of a single ampoule to about a week by using only small amounts of the drug to prepare the infusion on a daily basis. The
remainder of the drug can be aspirated from the ampoule under strict sterile precautions (preferably under a laminar flow system) and stored in a sealed 1-cc syringe for as long as a week. Reducing the maintenance dose to a minimum can also help prolong the availability.
In the absence of prostaglandin, atropine 0.02 mg/kg boluses may be used as 28 an alternative. For patients with transposition and intact ventricular septum, an umbilical venous catheter may be passed into the left atrium under fluoroscopic guidance and this could "stent" the atrial septum open to maintain reasonable oxygen saturations until transport to a center for balloon septostomy can be accomplished.