Causes of an elevated international normalized ratio in the intensive care unit and the implications for plasma transfusion

Vitamin K: a potential missing link in critical illness-a scoping review

BACKGROUND

Vitamin K is essential for numerous physiological processes, including coagulation, bone metabolism, tissue calcification, and antioxidant activity. Deficiency, prevalent in critically ill ICU patients, impacts coagulation and increases the risk of bleeding and other complications. This review aims to elucidate the metabolism of vitamin K in the context of critical illness and identify a potential therapeutic approach.

METHODS

In December 2023, a scoping review was conducted using the PRISMA Extension for Scoping Reviews. Literature was searched in PubMed, Embase, and Cochrane databases without restrictions. Inclusion criteria were studies on adult ICU patients discussing vitamin K deficiency and/or supplementation.

RESULTS

A total of 1712 articles were screened, and 13 met the inclusion criteria. Vitamin K deficiency in ICU patients is linked to malnutrition, impaired absorption, antibiotic use, increased turnover, and genetic factors. Observational studies show higher PIVKA-II levels in ICU patients, indicating reduced vitamin K status. Risk factors include inadequate intake, disrupted absorption, and increased physiological demands. Supplementation studies suggest vitamin K can improve status but not normalize it completely. Vitamin K deficiency may correlate with prolonged ICU stays, mechanical ventilation, and increased mortality. Factors such as genetic polymorphisms and disrupted microbiomes also contribute to deficiency, underscoring the need for individualized nutritional strategies and further research on optimal supplementation dosages and administration routes.

CONCLUSIONS

Addressing vitamin K deficiency in ICU patients is crucial for mitigating risks associated with critical illness, yet optimal management strategies require further investigation.

IMPACT RESEARCH

To the best of our knowledge, this review is the first to address the prevalence and progression of vitamin K deficiency in critically ill patients. It guides clinicians in diagnosing and managing vitamin K deficiency in intensive care and suggests practical strategies for supplementing vitamin K in critically ill patients. This review provides a comprehensive overview of the existing literature, and serves as a valuable resource for clinicians, researchers, and policymakers in critical care medicine.

Plasma transfusion in critically Ill patients with abnormal coagulation tests before invasive procedures: A propensity-adjusted cohort study

OBJECTIVE

To evaluate the association between plasma transfusion and bleeding complications in critically ill patients with an elevated international normalized ratios undergoing invasive procedures.

METHODS

A retrospective study was conducted to evaluate a consecutive sample of critically ill adult patients undergoing invasive procedures (N = 487) with an international normalized ratio ≥ 1.5 between January 1, 2019 and December 31, 2019. Among the followed patients, 125 were excluded due to incomplete case records and 362 were finally included in this investigation. The exposure was whether plasma had been transfused within 24 h before the invasive procedure. The primary outcome was the occurrence of postprocedural bleeding complications. Secondary outcomes included transfusion of red blood cells within 24 h of the invasive procedure, and additional patient-important outcomes such as mortality and length of stay. Tests were performed with univariate and propensity-matched analyses.

RESULTS

Of the 362 study participants, 99 (27.3 %) received a preprocedural plasma transfusion. In the propensity score-matched analysis, the rate of the occurrence of postprocedural bleeding complications between two groups was not statistically different (OR, 0.605[95 % CI, 0.341-1.071]; P = .085). The rate of postoperative red blood cell transfusion in the plasma transfusion group was higher than that in the non-plasma transfusion group (35.5 % vs 21.5 %; P < .05). No statistically significant difference in mortality was observed between the two groups (29.0 % vs 31.6 %; P = .101).

CONCLUSIONS

Prophylactic plasma transfusion failed to reduce postprocedural bleeding complications in ill critically patients with a coagulopathy. Meanwhile, it was associated with increased red blood cell transfusion after invasive procedures. Findings suggest that abnormal preprocedural international normalized ratios should be managed more conservatively.