Photo Credit: Berkozel

The following is a summary of “Haemoglobin values, transfusion practices, and long-term outcomes in critically ill patients with traumatic brain injury: a secondary analysis of CENTER-TBI,” published in the June 2024  issue of Critical Care by Guglielmi et al.

The ideal Hb thresholds and RBC transfusion approaches for traumatic brain injury patients (TBI) are still under debate.

Researchers conducted a retrospective study examining the link between Hb levels and long-term recovery in patients with TBI.

They conducted a secondary analysis of data from CENTER-TBI in European adult patients with TBI. The study focused on patients admitted to the ICU who had documented Hb levels upon admission and throughout the first week. Daily lowest Hb values during this initial 7-day period were analyzed as a continuous variable and categorized into three groups: less than 7.5 g/dL, between 7.5-9.5 g/dL, and greater than 9.5 g/dL. Anemia was defined as a Hb value below 9.5 g/dL. The analysis also described RBC transfusion practices in the ICU, categorizing them as “restrictive” or “liberal” based on the Hb thresholds used for transfusion decisions (e.g., transfusing at less than 7.5 g/dL compared to 7.5-9.5 g/dL).

The result showed that the Glasgow Outcome Scale Extended (GOSE) at 6 months, with scores less than 5 considered unfavorable. Among the 1,590 patients included, 1,231 had documented Hb values at admission. The mean Injury Severity Score (ISS) was 33 (SD 16), with 502 (40.7%) having isolated TBI and a mean Hb value of 12.6 (SD 2.2) g/dL at ICU admission. Only 121 (9.8%) patients had Hb levels below 9.5 g/dL, and 15 (1.2%) had levels below 7.5 g/dL. The RBC transfusions were given to 292 (18.4%) patients, with a median pre-transfusion Hb value of 8.4 (IQR 7.7–8.5) g/dL. A significant variability was observed in transfusion thresholds across centers. Multivariable logistic regression analysis indicated that higher Hb levels were independently associated with unfavorable neurological outcomes (OR 0.78; 95% CI 0.70–0.87). Similar findings were seen in patients with the lowest Hb levels within the first 7 days, with those having Hb <7.5 g/dL (OR 2.09; 95% CI 1.15–3.81) and those with Hb between 7.5 and 9.5 g/dL (OR 1.61; 95% CI 1.07–2.42) showing worse outcomes compared to those with Hb >9.5 g/dL. The results remained consistent when evaluating 6-month mortality. Higher Hb levels were linked to reduced mortality (OR 0.88; 95% CI 0.76–1.00), whereas Hb levels below 7.5 g/dL were related to increased mortality (OR 3.21; 95% CI 1.59–6.49).

Investigators concluded that anemia in patients with severe TBI worsens long-term neurological outcomes and increases mortality.

Source: ccforum.biomedcentral.com/articles/10.1186/s13054-024-04980-6