Hemodilution Causing Cerebral Desaturation

Mechanism of Injury

• Intraoperative anemia increases the risk for inadequate cerebral oxygen delivery.([FOOTNOTE=Habib RH, Zacharias A, Schwann TA, Riordan CJ, Durham SJ, Shah A. Adverse effects of low hematocrit during cardiopulmonary bypass in the adult: should current practice be changed? The Journal of thoracic and cardiovascular surgery. 2003;125(6):1438-1450.],[ANCHOR=View Abstract],[LINK=/content/mitg/websites/languagemasters/emea/en-gb/support/clinical-evidence.html?id=883102]) 
• Blood priming of the bypass circuit prevents cerebral desaturation in high-risk, low hematocrit coronary revascularization patients([FOOTNOTE=McCusker K, Chalafant A, de Foe G, Gunaydin S, Vijay V. Influence of hematocrit and pump prime on cerebral oxygen saturation in on-pump coronary revascularization. Perfusion. 2006;21(3):149-155.],[ANCHOR=View Abstract],[LINK=/content/mitg/websites/languagemasters/emea/en-gb/support/clinical-evidence.html?id=297511])
• Several clinical studies have demonstrated cerebral desaturation following hemodilution or blood loss([FOOTNOTE=Torella F, McCollum CN. Regional haemoglobin oxygen saturation during surgical haemorrhage. Minerva Med. 2004;95(5):461-467.],[ANCHOR=View Abstract],[LINK=/content/mitg/websites/languagemasters/emea/en-gb/support/clinical-evidence.html?id=297423]) ^, ([FOOTNOTE=Han SH, Bahk JH, Kim JH, et al. The effect of esmolol-induced controlled hypotension in combination with acute normovolemic hemodilution on cerebral oxygenation. Acta anaesthesiologica Scandinavica. 2006;50(7):863-868.],[ANCHOR=],[LINK=])

Associated Outcome

• The adverse ischemic effect of low hematocrit and hemoglobin during cardiopulmonary bypass is associated with poor postoperative outcome¹ and neurological impairment([FOOTNOTE=Mathew JP, Mackensen GB, Phillips-Bute B, et al. Effects of extreme hemodilution during cardiac surgery on cognitive function in the elderly. Anesthesiology. 2007;107(4):577-584.],[ANCHOR=View Abstract],[LINK=/content/mitg/websites/languagemasters/emea/en-gb/support/clinical-evidence.html?id=883111])