Recommendations for the safe use of direct oral anticoagulants in patients with cirrhosis based on a systematic review of pharmacokinetic, pharmacodynamic and safety data

PURPOSE

The popularity of direct oral anticoagulants (DOACs) is increasing among patients with cirrhosis. Cirrhosis has a major impact on the pharmacokinetics of drugs, potentially increasing adverse events. Safe use of drugs in cirrhosis requires a diligent risk-benefit analysis. The aim of this study is to develop practice recommendations for safe use of DOACs in cirrhosis based on a systematic review of pharmacokinetic, pharmacodynamic and safety data.

METHODS

We conducted a systematic literature search to identify studies on pharmacokinetics, pharmacodynamics and safety of DOACs in cirrhosis. Data were collected and presented in summary tables by severity of cirrhosis using the Child-Turcotte-Pugh (CTP) classification. A multidisciplinary expert panel evaluated the results and classified the DOACs according to safety.

RESULTS

Fifty four studies were included. All DOACs were classified as 'no additional risks known' for CTP A. For CTP B, apixaban, dabigatran and edoxaban were classified as 'no additional risks known'. Apixaban and edoxaban showed fewer adverse events in patients with cirrhosis, while dabigatran may be less impacted by severity of cirrhosis based on its pharmacokinetic profile. Rivaroxaban was classified as 'unsafe' in CTP B and C based on significant pharmacokinetic alterations. Due to lack of data, apixaban, dabigatran and edoxaban were classified as 'unknown' for CTP C.

CONCLUSION

DOACs can be used in patients with CTP A cirrhosis, and apixaban, dabigatran and edoxaban can also be used in CTP B. It is recommended to avoid rivaroxaban in CTP B and C. There is insufficient evidence to support safe use of other DOACs in CTP C cirrhosis.

Evaluation of the importance of mixing during preparation of antibiotic infusions

Background

The mixing step after medication addition to the infusion bag is frequently omitted during the preparation of drug infusions. However, the importance of mixing when preparing antibiotic infusions is still unknown.

Methods

The primary aim of this study was to assess the importance of the mixing step by comparing the concentrations of unmixed antibiotic infusions (cefuroxime, flucloxacillin, meropenem, and vancomycin) with the declared concentration at regular intervals during infusion. The secondary aim was to compare concentrations between preparation sites (hospital pharmacy versus clinical ward). Infusion bags were run through electronic infusion pumps. For cefuroxime, flucloxacillin, and meropenem, samples were collected 1, 15, and 20 min after starting the administration (infusion duration: 30 min). For vancomycin, samples were collected after 1, 60, and 110 min (infusion duration: 120 min). Vancomycin concentrations were measured using the Architect c4000 analyser and other concentrations using a validated UPC²-MS–MS multimethod.

Results

The median concentrations of the four antibiotics were comparable to the declared concentration at all three time points. No significant differences were found between preparation sites.

Conclusions

Spontaneous mixing occurred in the examined antibiotic solutions during normal handling.

Demonstrating circulation in vasculogenic mimicry patterns of uveal melanoma by confocal indocyanine green angiography

PURPOSE

Vasculogenic mimicry patterns, formed by highly invasive melanoma cells, connect to endothelial cell-lined blood vessels and contain fluid in vitroand in vivo. This study was designed to determine if fluid leaks into vasculogenic mimicry patterns without circulation, or if fluid circulates in and clears from these patterns.

METHODS

Indocyanine green (ICG) laser scanning confocal angiography (Heidelberg Retinal Angiograph (HRA); Heidelberg Engineering, Heidelberg, Germany) was performed on nine patients with posterior choroidal melanoma in an institutional setting. Blood was drawn before the ICG injection and from the contralateral arm of the ICG injection site and 1 min after the injection. Outcome measures include time to first filling of retinal vessels and vasculogenic mimicry patterns and the time at which no fluorescence could be detected by the HRA instrument. After fluorescence was no longer detected in vessels or patterns, the tubes containing the patient's blood was imaged by the Heidelberg HRA.

RESULTS

Looping vasculogenic mimicry patterns were detected focally in five patients within 30 s after injection and were detectable up to 12 min post-injection. Blood drawn before ICG injection did not autofluoresce but ICG-containing blood pooled in the tube continued to fluoresce at 1-month post-injection.

CONCLUSIONS

Vasculogenic mimicry patterns are not part of the endothelial cell-lined vascular system and fluid enters these patterns through leakage. The rapid infusion of ICG into these patterns after injection and the disappearance of fluorescence detectable by the Heidelberg HRA suggest that fluid circulates in these patterns and does not accumulate as a stagnant pool.

Computerised evaluation of visual fields

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