title: Efficacy and safety of using L-cysteine as a catheter-clearing agent for nonthrombotic occlusions of central venous catheters in children.
abstract: Critically ill pediatric patients, especially in the intensive care unit, receive multiple medications and have a higher risk of central venous catheter (CVC) occlusion. If an occlusion occurs immediately after the administration of multiple medications or incompatible medications, either an acidic solution such as 0.1 N hydrochloric acid (HCl) or a basic solution of 1 mEq/mL sodium bicarbonate or 0.1 N sodium hydroxide can be used. However, compounding and storing of 0.1 N HCl has become more complex due to USP <797> guidelines for sterile compounding, and an alternative is needed. We report a series of cases in which L-cysteine was used instead of HCl to clear CVCs occluded due to administration of multiple medications. L-cysteine is a commercially available, sterile solution with a pH of 1–2.5. CVC occlusion was resolved in 10 of the 16 episodes in 13 patients. Two of the 16 occlusions were phenytoin related and would not have responded. An L-cysteine dose of 50 mg was used during 10 of the 16 episodes, 100 mg during 5 episodes, and 25 mg during 1 episode. A correlation between catheter clearance and dose was not observed. Occlusion resolution due to L-cysteine was not correlated to the prior use of tissue plasminogen activator. Metabolic acidosis, adverse effects, or damage to the catheters due to L-cysteine were not observed. On the basis of this limited experience, we propose L-cysteine as an effective alternative to 0.1 N HCl for clearing CVC occlusions caused by drugs with an acidic pKa.
authors.affiliation: College of Pharmacy, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Vinita B
authors.initials: VB
authors.lastname: Pai
authors.forename: Steven
authors.initials: S
authors.lastname: Plogsted
mesh_terms: D000293:Adolescent; D000328:Adult; D061807:Catheter Obstruction; D002405:Catheterization, Central Venous / Q000379:methods*; D057785:Catheters; D062905:Central Venous Catheters; D002648:Child; D002675:Child, Preschool; D016638:Critical Illness; D003545:Cysteine; D004869:Equipment Safety; D005260:Female; D006801:Humans; D006851:Hydrochloric Acid; D007223:Infant; D008297:Male; D012189:Retrospective Studies; D012492:Salts; D055815:Young Adult
chemical_list: D012492:Salts; D003545:Cysteine; D006851:Hydrochloric Acid