Assessment of the Measurement Error in Cyclosporine Levels Drawn Between Peripheral and Central Sources

Correlation Between Tacrolimus Levels in Blood Samples Obtained from Central Catheter and Peripheral Venipuncture in Lung Transplant Patients (Ven-Cat Study)

BACKGROUND

Following lung transplantation (LT), receiving immunosuppressive therapy is crucial. Tacrolimus is considered a drug with a narrow therapeutic range and its use requires constant monitoring. This study aimed to evaluate the correlation between tacrolimus levels obtained from central venous catheter and direct venipuncture in adult patients undergoing LT.

METHODS

This prospective study included LT patients hospitalized in conventional ward carrying a central catheter through which no intravenous tacrolimus was administered. Trough samples were obtained through direct puncture and from the central catheter. Pearson correlation coefficient was calculated to quantify the mean difference between the 2 measures.

RESULTS

A total of 54 sample pairs from 16 LT patients were obtained, mostly male (81.3%) and bilateral transplant recipients (93.8%); the transplant procedure was the primary reason for admission (81.3%). The difference in tacrolimus levels between both samples was 0.3 (0.1-0.6) mcg/L, with the measurement for the samples obtained through venipuncture being mostly higher than that for those obtained from the catheter. A strong correlation was observed between the tacrolimus levels in the samples obtained from the catheter and through venipuncture (Pearson correlation coefficient, 0.991; P < 0.001; R2 = 0.982).

CONCLUSIONS

There is an excellent correlation between tacrolimus levels obtained from venipuncture and those obtained from central venous catheter in LT patients undergoing oral tacrolimus therapy.

Artificially Elevated Tacrolimus Concentrations Obtained From a Venous Catheter Previously Used for Tacrolimus Administration in a Pediatric Patient

Intravenous (IV) administration of calcineurin inhibitors, cyclosporine (CsA) and tacrolimus (TAC), has been associated with spuriously high serum concentrations collected from central venous catheters (CVCs) used for medication administration, secondary to reversible adsorption of medication to the catheter. Thus, therapeutic drug monitoring of IV CsA and TAC via CVCs previously exposed to these agents should be interpreted cautiously and ideally avoided. The duration of this effect is poorly characterized and the risk for extension of this effect to unexposed lumens of the same central catheter remains uncertain. We describe a case of a pediatric patient with artificially elevated serum TAC concentrations obtained from previously exposed and unexposed lumens of a central catheter, 27 days after last IV TAC administration.

Dual-lumen power injectable peripherally inserted central catheters in allogeneic hematopoietic stem cell transplantation: A prospective observational study

AIMS AND OBJECTIVES

To explore whether dual-lumen power injectable peripherally inserted central catheters (PICCs) could be effectively and safely applied in allogeneic hematopoietic stem cell transplantation (allo-HSCT) and for serum cyclosporine level monitoring.

BACKGROUND

Compared to conventional central venous access devices, PICC provides a feasible route not only for fluid infusion, but also for blood sample collection in patients undergoing oncological treatments.

DESIGN

A prospective observational study was conducted according to the STROBE guidelines.

METHODS

We prospectively evaluated the applications and complications of power injectable PICCs in 52 consecutive allo-HSCT recipients. We also compared the cyclosporine levels in 188 paired blood samples, simultaneously obtained via power injectable PICCs and percutaneous venous puncture, to investigate whether power injectable PICC is a feasible route for cyclosporine concentration monitoring in allo-HSCT.

RESULTS

The median PICC placement duration was 29 days. The insertion-site blood oozing and central line-associated bloodstream infection rates were 36.5% (19/52) and 26.9% (14/52), respectively, indicating the feasibility of these PICCs for various applications in allo-HSCT. No power injectable PICC-related thrombotic adverse events were identified; 90.4% (47/52) of cases with power injectable PICC removal occurred because of lack of medical utility, suggesting that power injectable PICC-related complications were manageable. However, cyclosporine levels in samples obtained via these PICCs were significantly higher than those in samples obtained via percutaneous venous puncture (261.5 ± 139.2 vs. 232.4 ± 253.6 ng/ml; p = 0.019 [set 1]; 254.8 ± 89.3 vs. 225.1 ± 233.3 ng/ml; p<0.001 [set 2]; 283.6 ± 103.9 vs. 238.0 ± 254.7 ng/ml; p = 0.006 [set 3]; 291.0 ± 94.9 vs. 266.0 ± 274.7 ng/ml; p = 0.016 [set 4]).

CONCLUSION

The power injectable PICC is a feasible venous access device for allo-HSCT.

RELEVANCE TO CLINICAL PRACTICE

The dual-lumen power injectable PICCs provided a reliable access for blood sample collection, decreasing the number of blind percutaneous venous punctures in allo-HSCT. However, its application in cyclosporine level monitoring needs further investigation.