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Visual incompatibility of morphine sulfate, furosemide and levofloxacin during Y-site
administration: about a case
Ame´lie Hugon, Se´bastien Chanoine, Sophie Schmidlin, Jean Calop, Benoit Allenet, Pierrick Bedouch
Pharmacy; Pharmacovigilance, Grenoble University Hospital, Grenoble, France
Background and objective: The simultaneous Y-site administration of injectable drugs through the veins can be responsible of physicochemical incompatibilities involving a loss of efficiency and/or a catheter obstruction with a risk of complication for the patient.
We report the practical management of the case of a physico-chemical incompatibility by acid/base reaction between morphine sulfate, furosemide and levofloxacin.
Design Case report: Setting Pneumology ward in university hospital with integration of clinical pharmacists. Main outcome measures Bibliographical researches: Trissel Handbook on injectable drugs, Vidal, Theriaque and Stabilis database.
Results:A 73 years-old man, hospitalized for pulmonary arterial hypertension with oedema, showed a limited venous access; a one way catheter was set up. Two drugs were put in the drip: a furosemide continuous infusion (5 mg/ml) and a 1-h levofloxacin infusion twice a day (5 mg/ml). These two drugs were simultaneously put in a drip for 2 days during week-end (no pharmacist present in ward) with no visual precipitation whereas incompatibility between levofloxacin and furosemide was described [1]. At the third day, a morphine sulphate continuous infusion (0.8 mg/ml) was added for severe pain. Before levofloxacin infusion, there was no visual precipitation. At the end of the levofloxacin infusion, the nurse noticed a flow drop and the formation of a white crystal precipitate appearing at the Y junction level. The infusions were immediately stopped and the drip was removed. Then, the levofloxacin and morphine sulfate infusions were restarted and furosemide was replaced by oral formulation. No incompatibility was observed with this treatment.
Conclusions: The incompatibility between furosemide and morphine sulphate is well documented. Indeed, furosemide solution has a basic pH (pH = 9) and precipitates when pH is below 5.5. Morphine sulphate solution is acid (pH = 3–4.5).
We suggested that the addition of morphine sulphate removed the buffer effect of furosemide which probably induced a precipitation with levofloxacin. This simple case shows the importance in managing simultaneously Y-site administered injectable drugs when more than two drugs are simultaneously administered.
Reference: Saltsman C, et al. Compatibility of levofloxacin with 34 medications during simulated Y-site administration. Am J Health Syst Pharm. 1999;56(14):1458–9.
Email AHugon@chu-grenoble.fr
