Accuracy of preparation of i.v. medication syringes for anesthesiology.

PURPOSE: The results of a study of the accuracy of i.v. medication preparation by anesthesiologists are presented. METHODS: The accuracy of syringe preparation was assessed by analyzing the contents of 500 unused syringes collected after adult and pediatric surgery procedures. The collected syringes contained various i.v. medication formulations representative of different preparation techniques: atracurium 1, 2.5, and 5 µg/mL and fentanyl 10, 20, 25, and 50 µg/mL, which required serial dilution after withdrawal of the drugs from ampuls; thiopental 5, 25, and 50 mg/mL, prepared by diluting reconstituted powdered drug from vials; and lidocaine 10-mg/mL solution, which was withdrawn directly from the ampul into a syringe. Variances between actual and labeled drug concentrations were determined via a validated ultraviolet-visible light spectro-photometry method. RESULTS: Overall, 29% of the evaluated syringes were found to contain drug concentrations outside the designated range of acceptability (±10% of the targeted concentration); 18% of preparations deviated from the declared dose by ±20%, 8% deviated by ±50%, and 4% deviated by ±100%. In one instance, the actual drug concentration was at variance with the labeled concentration by >100%. In 4% of cases (n = 20), discrepancies exceeded 100%, suggesting not just imprecision but errors in the preparation process, such as incorrect dilution calculations and selection of the wrong medication vial by the syringe preparer. CONCLUSION: Analysis of different i.v. formulations of four medications prepared in syringes by anesthesiologists revealed a high rate of discrepancies between ordered and actual drug concentrations, suggesting a need for increased institutional efforts to prevent errors during the preparation process.

Microbial contamination of syringes during preparation: the direct influence of environmental cleanliness and risk manipulations on end-product quality.

PURPOSE: The direct influence of environmental cleanliness and risk manipulations on prepared syringes was evaluated. METHODS: Media-fill testing was used to estimate potential microbial contamination. Syringes were prepared in three different environments using four different uncontrolled high-risk manipulations. The three environments included an International Organization for Standardization (ISO) class 5 horizontal laminar-airflow hood in an ISO class 6 cleanroom (in accordance with United States Pharmacopeia [USP] chapter 797), an ISO class 7 drug preparation area of an operating room, and an uncontrolled decentralized pharmacy in a ward. For each combination of environment and manipulation, 100 syringes were filled by a single operator. The four high-risk manipulations used included simple filling of syringes with trypticase soy broth, three-second contact by the ungloved fingers of the operator with the hub of the syringe, three-second contact between an object and the hub of the syringe, and exposure of the filled syringes to ambient air for 10 minutes. RESULTS: Of the 1500 syringes prepared in three different environments, none produced within the cleanroom contained microorganisms, 6% were contaminated in the operating room, and 16% were contaminated in the ward (p < 0.0001). Certain high-risk manipulations were associated with a significant increase in the contamination of the surrogate syringes, including exposure to nonsterile ambient air and nonsterile objects or fingers (p < 0.0001). CONCLUSION: High contamination rates were measured when the hub of syringes touched nonsterile environmental surfaces and fingers, whereas the drawn-air manipulation was associated with a lower risk of contamination. Working within a properly operating unidirectional airflow primary engineering control in an ISO class 5 cleanroom in accordance with USP chapter 797 requirements was demonstrated to be the best way to avoid bacterial or fungal contamination of injectable drugs directly resulting in patient infections.

I.v. N-acetylcysteine and emergency CT: use of serum creatinine and cystatin C as markers of radiocontrast nephrotoxicity.

OBJECTIVE: The purpose of this study was to assess the effect of i.v. administration of N-acetylcysteine (NAC) on serum levels of creatinine and cystatin C, two markers of renal function, in patients with renal insufficiency who undergo emergency contrast-enhanced CT. SUBJECTS AND METHODS: Eighty-seven adult patients with renal insufficiency who underwent emergency CT were randomized to two groups. In the first group, in addition to hydration, patients received a 900-mg injection of NAC 1 hour before and another immediately after injection of iodine contrast medium. Patients in the second group received hydration only. Serum levels of creatinine and cystatin C were measured at admission and on days 2 and 4 after CT. Nephrotoxicity was defined as a 25% or greater increase in serum creatinine or cystatin C concentration from baseline value. RESULTS: A 25% or greater increase in serum creatinine concentration was found in nine (21%) of 43 patients in the control group and in two (5%) of 44 patients in the NAC group (p = 0.026). A 25% or greater increase in serum cystatin C concentration was found in nine (22%) of 40 patients in the control group and in seven (17%) of 41 patients in the NAC group (p = 0.59). CONCLUSION: On the basis of serum creatinine concentration only, i.v. administration of NAC appears protective against the nephrotoxicity of contrast medium. No effect is found when serum cystatin C concentration is used to assess renal function. The effect of NAC on serum creatinine level remains unclear and may not be related to a renoprotective action.