Table 1.
Results of selected studies on cerebral tissue oxygenation, measured by NIRS.
| References | Study design, No. infants | GA/BW | Study population | Outcome measure | RBC transfusion practice | Hb- / Ht-level | Cerebral oxygenation |
|---|---|---|---|---|---|---|---|
| Goldstein et al. (30) | Cohort study, n = 31 | <1,500 g and <35 wks | Anemic infants in need for RBC-tx | RcSO2; 1 h < RBC to 24 h > RBC | 10–15 ml/kg in 3–5 h | Mean Ht increased from 31.4 to 37.4% | Anemia was associated with lower rcSO2; RcSO2 during and after RBC-tx did not differ by anemia status |
| Whitehead et al. (31) | Cohort study, n = 39 | <30 wks | From 2nd wk PNA through 36 wks PMA | cFTOE; 8 h weekly | Volume NA; administered in 2 h | Median Hb was 9.9 g/dL; 69% had a measured Hb-level below 10 g/dL | Anemia was associated with critically increasing cFTOE, occurring at Hb-level of 9.6 g/dL |
| Jani et al. (32) | Cohort study, n = 40 | <32 wks | Anemic infants in need for RBC-tx | RcSO2; 2 h < RBC to 4 h > RBC, and 24 h > RBC | 15 ml/kg in 4 h | Mean Hb increased from 9.7 to 13.0 g/dL | Using liberal transfusion thresholds did only show a trend toward increasing rcSO2 after RBC-tx; Differences were more pronounced 24 h later |
| Aktas et al. (33) | Cohort study, n = 35 | <33 wks | Anemic infants in need for RBC-tx | RcSO2; 24 h < RBC and 24 h > RBC | 15–20 ml/kg in 3 h | Median Hb increased from 7.8 to 11.0 g/dL | RcSO2 was mostly maintained within normal limits during anemia and increased non-significantly after the RBC-tx |
| Jain et al. (34) | Cohort study, n = 30 | <32 wks | Anemic infants in need for RBC-tx | RcSO2; 1 h < RBC and 1 h > RBC | 15 ml/kg in 3 h | Mean pre-RBC-tx Hb was 9.8 g/dL | Mean rcSO2 increased after RBC-tx and was correlated with anemia severity and cardiac output-weighted oxygen delivery index |
| Saito-Benz et al. (35) | Cohort study, n = 24 | <34 wks | Anemic infants in need for RBC-tx | RcSO2; 1 h < RBC, 24 h > RBC, and 5 d > RBC | 15 ml/kg | Mean pre-RBC-tx Hb was 8.6 g/dL | RBC-tx led to an immediate increased rcSO2, but this change attenuated to baseline by 5 days |
| Kalteren et al. (36) | Case-control study, n = 8/16 |
<32 wks | Anemic infants in need for RBC-tx | RcSO2; 12 h > RBC | 15 ml/kg in 3 h | Median Hb increased from 10.8 to 14.0 g/dL | RcSO2 and its variability remained stable during and after RBC-tx in infants that did not develop necrotizing enterocolitis |
| Mintzer et al. (37) | Cohort study, n = 27 | <1,250 g | During first 10 days PNA | cFTOE; continuous | NA | Mean Ht was 39.7% | cFTOE was inversely correlated with Ht |
| Whitehead et al. (38) | Cohort study, n = 68 | <30 wks | From 2nd wk PNA through 36 wks PMA | RcSO2; 8 h weekly | 15 ml/kg | Median Hb was NA; 68% had a measured Hb-level below 10 g/dL | Increasing degree of anemia with progressive decrease in rcSO2; Critical Hb threshold for rcSO2 desaturation was 9.5 g/dL |
| Li et al. (39) | Case-Control study, n = 45/10 |
<32 wks | Anemic infants in need for RBC-tx; controls | RcSO2; 1.5 h < RBC to 2 h > RBC | Volume NA; administered in 3 h | Pre-RBC-tx Hb was below 14.4, 12.0, or 9.0 g/dL | Anemia reduces brain oxygen supply gradually to anemia severity; During and following RBC-tx rcSO2 peaked and remained stable |
| El-Dib et al. (40) | Cohort study, n = 72 | <1,500 g and <34 wks | During 1st wk PNA and once after 1st wk PNA | cFTOE; weekly | NA | Mean Hb was 12.4 g/dL | Hb significantly affected cFTOE; cFTOE increased with reduced Hb |
| Banerjee et al. (41) | Cohort study, n = 59 | <34 wks | Anemic infants in need for RBC-tx | RcSO2; 15 m < RBC to 15 m > RBC | 15 ml/kg in 3 h | Mean Hb increased from 11.2 to 13.0 g/dL (1–7 days PNA), vs. 10.3 to 13.5 g/dL (8–28 days PNA), and vs. 9.1 to 12.2 g/dL (>28 days PNA) | Mean rcSO2 increased following RBC-tx in 3 different PNA groups, more pronounced after 28 days PNA |
| Andersen et al. (42) | Cohort study, n = 24 | <29 wks | Anemic infants in need for RBC-tx on 1st day PNA | cFTOE; 30 m < RBC and 60 m > RBC | 15 ml/kg in 3 h | Mean Hb increased from 11.5 to 12.6 g/dL (low pre-RBC-tx cFTOE), vs. 12.0 to 13.3 g/dL (high pre-RBC-tx cFTOE) | RBC-tx lowered cFTOE in infants with high pre-transfusion cFTOE |
| Mintzer et al. (43) | Case-Control study, n = 10/9 |
<1,250 g | Infants receiving “booster-” RBC-tx 1st wk PNA; controls | RcSO2 and cFTOE; continuous for 7 d | 15 ml/kg in 3–4 h | Mean Ht was 35.2% in transfused infants vs. 43.5% in non-transfused infants | RBC-tx increased rcSO2 and reduced cFTOE irrespective of pre-transfusion Ht; No changes in non-transfused neonates |
| Sandal et al. (44) | Case-Control study, n = 23/16 |
<30 wks | Anemic infants in need for RBC-tx > 1st month PNA; controls | RcSO2; 10 h < RBC to 10 h > RBC | 15 ml/kg in 2–4 h | Mean pre-RBC-tx Hb and Ht were 8.7 g/dL and 25% in transfused infants (with a significant increase after RBC-tx) vs. 12.3 g/dL and 37% in non-transfused infants | RcSO2 was lower in anemic infants than controls; RBC-tx improved rcSO2 independent of transfusion duration |
| Koyano et al. (45) | Cohort study, n = 19 | <1,250 g | Anemic infants in need for RBC-tx > 48 h PNA | RcSO2; 6 h < RBC and 2–6 h>RBC | 10–28 ml/kg | Median Hb increased from 9.3 to13.7 g/dL | RcSO2 increased by RBC-tx; greater CBF decrease in low pre-transfusion Hb infants |
| Seidel et al. (46) | Cohort study, n = 76 | <32 wks | Anemic infants in need for RBC-tx | RcSO2; 4 h < RBC, during RBC, 4 h > RBC and 24 h > RBC | 80 * weight in kg * (desired Ht-current Ht)/donor-Ht ml in 4 h | Mean Ht increased from 27.6 to 48.3% (low pre-RBC-tx rcSO2), vs. 27.3% to 47.7% (high pre-RBC-tx rcSO2) | RcSO2 increase until 24h after RBC-tx; Higher rcSO2 increase and less frequent desaturations after RBC-tx in infants with lower pre-transfusion rcSO2 values; No correlation between baseline rcSO2 and pre-RBC-tx Ht |
| Bailey et al. (47) | Cohort study, n = 30 | <37 wks | Anemic infants in need for RBC-tx > 5 d PNA | RcSO2; 20 m < RBC to 20 m > RBC and 12 h > RBC | 15 ml/kg in 4 h | Mean Hb and Ht increased from 9.3 g/dL and 27.6% to 12.4 g/dL and 36.5% | RcSO2 increased after RBC-tx and remained elevated 12 h after it began; No correlation was found between rcSO2 and Hb-levels |
| Dani et al. (48) | Cohort study, n = 15 | <30 wks | Anemic infants in need for RBC-tx | RcSO2; 60 m < RBC to 60 m > RBC | Mean 28 ml/kg at 5 ml/kg/h | Mean Ht increased from 27.1 to 43.3% | RBC-tx followed by increased rcSO2, decreased cFTOE and reduced CBF velocity |
| Van Hoften et al. (7) | Cohort study, n = 33 | <35 wks | Anemic infants in need for RBC-tx | RcSO2; 1 h < RBC, 1 h > RBC and 24 h > RBC | 15 ml/kg in 3 h | Median Hb and Ht increased from 11.1 g/dL and 31% to 13.5 g/dL and 40% | Following RBC-tx rcSO2 increased and cFTOE decreased quickly; RcSO2 might be at risk when Hb <9.7 g/dL |
| Dani et al. (15) | Cohort study, n = 14 | <34 wks | Anemic infants in need for RBC-tx 7 d PNA to <1st month PNA | RcSO2; 30 m < RBC to 30 m > RBC | 25 ml/kg at 5 ml/kg/h | Mean Hb and Ht increased from 9.1 g/dL and 28% to 14.6 g/dL and 45% | RBC-tx improves cerebral oxygen supply and decreases cerebral blood volume (increase cerebrovascular resistance) |
| Wardle et al. (49) | Case-Control study, n = 46/43 |
<32 wks | Anemic infants in need for RBC-tx; stable controls | cFTOE; 10 m once and 10 m 12–24 h > RBC | 20 ml/kg | Median Hb increased from 12.3 to 15.2 g/dL; Hb-level in controls was 14.0 g/dL | cFTOE was similar between anemic infants and controls; After RBC-tx cFTOE decreased in transfused infants; cFTOE was inversely correlated with Hb |
NIRS, near-infrared spectroscopy; GA, gestational age; BW, birth weight; RBC-tx, red blood cell transfusion; NA, not applicable; rcSO2, cerebral regional tissue oxygen saturation; cFTOE, cerebral fractional tissue oxygen extraction; PNA, postnatal age; PMA, postmenstrual age; Hb, hemoglobin; Ht, hematocrit; CBF, cerebral blood flow; SaO2, arterial oxygen saturation; d, day; h, hour; m, minutes.