1. Cohen, Michael R. ScD, MS, RPh

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These similarities could lead to mix-ups

Be aware that Hospira's 5 mg/2 mL ampules of verapamil, a calcium channel blocker, and 100 mcg/2 mL ampules of fentaNYL, an opioid, share the same light tan labels and tan and blue colored bands along the ampule neck, as shown below. Because of the similarities, the risk of confusing these two products is high. A representative from Hospira reports that a label revision is in the process for the verapamil product. In the meantime, safety measures include storing the products separately (because fentaNYL is a controlled substance, it shouldn't be stored near verapamil), purchasing the drugs from different manufacturers, and preparing doses in the pharmacy.



Wrong syringe contributes to 10-fold overdose

During a code, a physician verbally ordered regular insulin and 50% dextrose for a patient whose serum potassium level was 8 mEq/L (normal, 3.5 to 5 mEq/L). The physician didn't specify a dose, apparently assuming that the pharmacist at the code knew the dose of insulin needed to treat hyperkalemia. The pharmacist quickly prepared a 1 mL (100 units) dose of regular insulin instead of the usual 10-unit dose, and then diluted the insulin in 50 mL of 50% dextrose. To draw up the insulin dose, the pharmacist used a 3 mL syringe. Because of time constraints typical during a code, the pharmacist didn't ask another practitioner for an independent double-check.


The 50% dextrose with 100 units of insulin was administered I.V. over 15 minutes. The patient couldn't be resuscitated. Because the patient's condition had been so critical before the error, it's unclear whether the insulin overdose played a role in his death.


Typically, U-100 insulin syringes have an attached needle, which doesn't allow I.V. administration of the medication via a needleless port. Thus, clinicians sometimes use 3 mL syringes for this purpose, even though it's difficult to measure a 10-unit (0.1 mL) dose with this syringe. Instead, they should use a U-100 insulin syringe with a Luer connector. Another recommendation is to establish standard hyperkalemia treatment protocols that specify, among other criteria, the insulin type, dose, and route of administration.



Keep this plunger under pressure

Nurses must remember to maintain pressure on the syringe plunger rod of any Simplist prefilled syringe (Fresenius Kabi) during I.V. drug administration via an I.V. port or stopcock attached to a running I.V. infusion line. Due to a drug shortage, a hospital that typically used Carpuject prefilled syringes of Dilaudid (HYDROmorphone) 1 mg/mL obtained a supply of the drug in Simplist prefilled syringes. A nurse needed to administer Dilaudid as a slow I.V. push via a patient's free-flowing maintenance I.V. line. She attached the syringe to a stopcock on the I.V. tubing, intending to administer small doses in increments as prescribed. After part of the dose had been administered, the nurse turned to document the dose on a bedside computer, leaving the syringe attached to the stopcock without maintaining pressure on the plunger rod. When she turned around, she saw that the syringe plunger rod had been ejected from the syringe barrel (see photo) and that the I.V. maintenance solution was free-flowing out of the back of the syringe. Simplist syringes have a glass barrel that lacks a retaining ring (also called a backstop or positive stop) to prevent the plunger rod from popping out with back pressure from a running I.V. solution.


Even some small syringes may not have enough positive stop to prevent the plunger rod from popping out of the barrel if the pressure from the maintenance I.V. infusion is high enough. When administering small amounts of a drug from any syringe with a wait between incremental doses, always maintain thumb pressure on the plunger rod and never leave the syringe in place by itself while attached to an I.V. port or stopcock.

Figure. Simplist syr... - Click to enlarge in new windowFigure. Simplist syringe with the plunger rod removed.