Some drugs prepared for intravenous infusion may be absorbed out of the solution onto the walls of the infusion set. This can result in less drug than expected being given to the patient, which can result in underdosing.
Materials that may absorb drugs:
(1) polyvinyl chloride (PVC) plastic
(2) glass
(3) nylon
|
Drug |
PVC |
Glass |
Nylon |
|
chlormethiazole |
X |
|
X |
|
diazepam |
X |
|
|
|
insulin |
X |
X |
X |
|
nimodipine |
X |
|
|
|
nitroglycerin, organic nitrates |
X |
|
X |
|
phenothiazines |
X |
|
|
|
thiopental |
X |
|
|
|
warfarin sodium |
X |
|
|
where:
• Phenothiazines include chlorpromazine, promethazine, thioridazine and trifluoperazine.
The amount of drug absorbed is affected by:
(1) concentration of the drug
(2) length of time in contact
(3) flow rate
(4) surface area of infusion set
Options for handling:
(1) Use an infusion set made of a material that will not absorb the drug
(1a) Non-PVC (polyethylene) or glass for drugs absorbed onto PVC.
(1b) Use a syringe infusion pump.
(2) Increase the amount of drug in the infusion to compensate for absorption (unpredictable).
(3) Closer monitoring with adjustment of the infusion rate.
(4) Using an infusion set with less internal surface area (short lengths of small gauge tubing, small bags).
Specialty: Pharmacology, clinical
ICD-10: ,
