Preoperative hematocrit and platelet count are associated with blood loss during spinal fusion for children with neuromuscular scoliosis

Abstract

Aim To assess the relationship of preoperative hematology laboratory results with intraoperative estimated blood loss and transfusion volumes during posterior spinal fusion for pediatric neuromuscular scoliosis. Methods Retrospective chart review of 179 children with neuromuscular scoliosis undergoing spinal fusion at a tertiary children’s hospital between 2012 and 2017. The main outcome measure was estimated blood loss. Secondary outcomes were volumes of packed red blood cells, fresh frozen plasma, and platelets transfused intraoperatively. Independent variables were preoperative blood counts, coagulation studies, and demographic and surgical characteristics. Relationships between estimated blood loss, transfusion volumes, and independent variables were assessed using bivariable analyses. Classification and Regression Trees were used to identify variables most strongly correlated with outcomes. Results In bivariable analyses, increased estimated blood loss was significantly associated with higher preoperative hematocrit and lower preoperative platelet count but not with abnormal coagulation studies. Preoperative laboratory results were not associated with intraoperative transfusion volumes. In Classification and Regression Trees analysis, binary splits associated with the largest increase in estimated blood loss were hematocrit ≥44% vs. <44% and platelets ≥308 vs. <308 × 109/L. Conclusions Preoperative blood counts may identify patients at risk of increased bleeding, though do not predict intraoperative transfusion requirements. Abnormal coagulation studies often prompted preoperative intervention but were not associated with increased intraoperative bleeding or transfusion needs.

Perioperative Risk Factors for Bleeding in Adolescents Undergoing Pedicle Screw Instrumentation for Scoliosis

“…Lewen et al observed the relationship between preoperative hematology laboratory results and intraoperative blood loss in spinal fusion in NMS patients. They found that higher preoperative hematocrit and lower platelet count increased intraoperative blood loss [23]. In current study, lower platelets were potential risk factors for greater intraoperative bleeding in the AIS group, but none of these laboratory results correlated with the amount of intraoperative bleeding in the multivariable regression analysis.…”

“…In previous studies, longer operative time, lower BMI, more extensive fusion, larger preoperative cobb angle for main curve, and platelet levels have played roles in more extensive bleeding concerning AIS patients [17][18][19][20][21]. In comparison, in NMS patients, lower BMI, higher age, larger preoperative main curvature, preoperative hematocrit, older age, and number of osteotomies have been described to influence more voluminous intraoperative bleeding [22][23][24][25].…”