Cerebral Haemodynamic Changes by Red Blood Cell Transfusion in Neonates
Condition: Cerebral Haemodynamics; Erythrocyte Transfusion
Study type: Observational

Summary: 
      The timing and the indications for red blood cell (RBC) transfusions remain one of the most
      controversial topic in Neonatology. Indeed, biomarkers routinely used to discriminate between
      patients that will benefit from RBC transfusion appear insufficient. Tissue oxygenation could
      be useful to determine the need for transfusion.

      This study aims to assess the effects of RBC transfusion on cerebral haemodynamics and
      oxygenation in neonates with a new hybrid optical device (BabyLux) integrating time-resolved
      spectroscopy (NIRS-TRS) and diffuse correlation spectroscopy (DCS).

      It is hypothesized that cerebral blood flow decreases after RBC transfusion, whereas cerebral
      oxygenation and oxygen metabolism are unchanged.
    

Detailed description: 
      The BabyLux hybrid setup can determine the following parameters in the same tissue sample
      non-invasively and continuously with a high temporal resolution (0.1-0.2 Hz):

        -  Cerebral blood flow index (CBFi), i.e. an index that is proportional with CBF

        -  Concentration of oxyhaemoglobin (O2Hb)

        -  Concentration of deoxyhaemoglobin (dHb)

        -  Total haemoglobin concentration (tHb)

        -  Tissue oxygen saturation (rStO2)

        -  Cerebral metabolic rate of oxygen index (CMRO2i), i.e. an index that is proportional
           with CMRO2 Hence, the BabyLux device allows assessment of key parameters of cerebral
           haemodynamics and, in particular, to examine if the percentage change of cerebral
           metabolic rate for oxygen is close to the expected zero, as an external quality control
           of the separate NIRS parameters.

      There are no studies on RBC transfusion in neonates evaluating cerebral haemodynamic
      utilizing DCS and TRS combined.

      Hence, primary aim of this study is:

      - to assess the effect of RBC transfusion on cerebral haemodynamics and oxygenation as
      measured by the Babylux device.

      Secondary aims are:

        -  to quantify the effect of estimated ∆[Hb] on the differential path length factor (DPF);

        -  to compare two different NIRS devices and techniques. BabyLux measurement will be
           performed before and after RBC transfusion, whereas during RBC transfusion cerebral
           oxygenation will be monitored with a spatially resolved continuous wave (CW) NIRS.
    

Intervention name(s): Erythrocyte transfusion
Intervention type(s): Other
Intervention description(s): The cerebro-vascular effects of a clinically prescribed erytrocyte (red blood cell) transfusion is examined. Before the transfusion, BabyLux sensor is placed on the neonatal fronto-parietal region and held in place by a self-adhesive bandage. A baseline prior to transfusion is established through a series of five repeated measurements of 1 minute taken during a stable period just before the transfusion is started. Once transfusion has ended, another series of five repeated measurements of 1 minute taken during a stable period are performed to determine the responses. Cerebral oxygenation as determined by a commercial spatially resolved NIRS device with neonatal sensor will be continuously recorded during transfusion.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Newborn infants admitted to a neonatal intensive care unit and who need an erythrocyte
        transfusion