Intravenous nitroglycerin perfusion techniques--clinical implications

Two types of intravenous nitroglycerin (NTG) perfusion sets were studied using laboratory techniques. A known concentration of NTG was placed in each of these sets, and an evaluation was made as to the dose of NTG actually received by the patient after passage of the NTG solution through the sets. Set number one consisted of a glass container and polyvinyl chloride (PVC) tubing. After passage through this set, there was a rapid and significant decrease in the NTG concentration, i.e. the dose actually received by the patient is less than the dose theoretically administered. Set number two consisted of a polypropylene syringe and polyethylene tubing. After passage through this set, there was no significant change in the NTG concentration, i.e. the patient receives the full theoretical dose.