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.

Hexadecyl-Containing Organic Salts as Novel Organogelators for Ionic, Eutectic, and Molecular Liquids.

The incorporation of a hexadecyl group on imidazolium, pyridinium, and pyrrolidinium scaffolds produces low-molecular-weight ionic organogelators that can gel several types of ionic liquids, deep eutectic solvents (DESs), and several molecular organic solvents. Minimum gelator concentrations fall in the 0.9-15.0% (w/v) range, with the lower end of the gelator concentrations observed in the gelation of DESs. On the basis of polarized optical microscopy, differential scanning calorimetry, and X-ray data, crystallization of these salts appear to produce high-surface-area crystals, which generate sufficiently stable three-dimensional networks that are capable of trapping the solvent molecules. Importantly, the nature of the fluid component of the gel appears to have a profound effect on the morphology of the crystallized organogelators. On the other hand, the organogelators appeared to modulate phase transitions of the liquids.