Udo Steigerwald

Background/Objectives: The gold standard for cerebrospinal fluid leukocyte counting is manual counting in a Fuchs–Rosenthal chamber. Recent advances in automated body-fluid-counting systems, offering a time- and labor-saving solution, are challenging this dogma. Yet, the equivalence of diagnostic accuracy is still debated in the community. Methods: We compared manual and automated cell counting of cerebrospinal fluid samples of lumbar punctures and extraventricular drains with both low and high leukocyte counts, shedding light on the variability of results between man and machine. Results: Automated and manual cell counting showed a strong correlation across all samples, particularly in the subgroup of patients with fewer than 20 cells/µl, where outliers could become especially clinically relevant. Conclusions: We found the automated counting system to be highly accurate and not lacking in diagnostic sensitivity even at low cell counts, making it a powerful tool when used in the right clinical setting.

Background: Anemia remains one of the most common comorbidities in intensive care patients worldwide. The cause of anemia is often multifactorial and triggered by underlying disease, comorbidities, and iatrogenic factors, such as diagnostic phlebotomies. As anemia is associated with a worse outcome, especially in intensive care patients, unnecessary iatrogenic blood loss must be avoided. Therefore, this scoping review addresses the amount of blood loss during routine phlebotomies in adult (>17 years) intensive care patients and whether there are factors that need to be improved in terms of patient blood management (PBM). Methods: A systematic search of the Medline Database via PubMed was conducted according to PRISMA guidelines. The reported daily blood volume for diagnostics and other relevant information from eligible studies were charted. Results: A total of 2167 studies were identified in our search, of which 38 studies met the inclusion criteria (9 interventional studies and 29 observational studies). The majority of the studies were conducted in the US (37%) and Canada (13%). An increasing interest to reduce iatrogenic blood loss has been observed since 2015. Phlebotomized blood volume per patient per day was up to 377 mL. All interventional trials showed that the use of pediatric-sized blood collection tubes can significantly reduce the daily amount of blood drawn. Conclusion: Iatrogenic blood loss for diagnostic purposes contributes significantly to the development and exacerbation of hospital-acquired anemia. Therefore, a comprehensive PBM in intensive care is urgently needed to reduce avoidable blood loss, including blood-sparing techniques, regular advanced training, and small-volume blood collection tubes.