Is NPO (Nil Per Os) Order Helping or Hindering Elective Cardiac Procedures?

The practice of fasting before elective cardiac procedures including cardiac catheterization and transesophageal echocardiography is commonly implemented but evidence for these requirements is lacking. Fasting periods often exceed the intended length of time, increasing the risk of irritability, dehydration, acute kidney injury, hypoglycemia, and length of hospitalization. The practice of perioperative fasting relies on the premise that aspiration during general anesthesia can be mitigated by minimizing the volume of gastric contents, and stomach acidity. But the evidence has shown that fasting does not guarantee an empty stomach, and there is no observed association between aspiration and compliance with common fasting guidelines. Elective cardiac procedures are performed using procedural sedation, where the risk of serious aspiration is small. In most patients, we argue, that strict fasting requirements should be reduced, and a more nuanced fasting protocol based on individual patient characteristics and risk factors should be utilized given the overall low risk of aspiration with elective procedures utilizing procedural sedation. In this review, we examine the historical origins and current evidence relating to the practice of fasting as it relates to cardiac catheterization and transesophageal echocardiography.