Nadir hematocrit during cardiopulmonary bypass: End-organ dysfunction and mortality

Abstract

Although red blood cell transfusion has associated morbidity risk, there must be a tradeoff between adverse effects of low hematocrit during cardiac surgery and those of transfusion. The strong association of nadir hematocrit with preoperative hematocrit suggests the need for investigation and optimization before elective cardiac surgery.

Cardiovascular surgery in Jehovah's Witness patients: The role of preoperative optimization

“…23 Preoperative anemia has been implied as a predictor of morbidity and mortality after cardiac surgery, 24,25 whereas others argue that the low hematocrit is just the threshold for blood transfusion and the transfusion itself is causing the harm. 23,26 Because our data are obtained from bloodless cardiovascular surgery, it provides support to the fact that preoperative anemia is an important independent factor associated with postoperative adverse outcomes.…”

Patient-oriented blood-saving concept in operations with cardiopulmonary bypass

“…1). Авторы также отмечают корреляцию между увеличением значений гематокрита и частотой ис-пользования аллогенных продуктов крови в периопера-ционном периоде [9]. Характерно, что в исследуемой группе у 6 (12,2%) пациентов трансфузия была обусловле-на хирургическим кровотечением, а в остальных случаях проводилась у пациентов с исходно низким гематокритом в ближайший послеоперационный период.…”

Introducing Blood Conservation Into Clinical Practice

“…Variation in transfusion triggers, patient-specific morbidity, and clinical settings may contribute to some of the observed variability in transfusion rates among published reports. For example, although guidelines in the cardiac surgical setting suggest a lower boundary of acceptable hemoglobin, there is evidence to suggest that patient morbidity is higher at lower levels of anemia [37][38][39] (Figures 2 and 3). A recent publication examined the relationship between nadir hematocrit and end-organ dysfunction in a cohort of more than 7,900 patients.…”

“…The increased risk varied depending upon patient-specific factors such as age, comorbidities, level of nadir hematocrit, and the morbidity outcome under investigation. 37 The varying views among healthcare providers on the morbidity risk trade-off between anemia and transfusion certainly factors into the observed variability surrounding transfusion practices.…”

“…37 Lower nadir hematocrit values are often the trigger for transfusions; effective blood management can reduce the contribution of preoperative anemia to the lower intraoperative levels and subsequent transfusion risk. However, variable adoption of institutional blood management programs nationally may be influencing the observed variability surrounding transfusion.…”