Utilization of epinephrine-soaked gauzes to address bleeding from osteotomy sites in non-tourniquet total knee arthroplasty: a retrospective cohort study

Table 4 Comparison of differences in blood loss

	Epinephrine group (N = 51)	No epinephrine group (N = 50)	P value
Calculated blood loss^a# (mL)	735.9 (293.7)	847.7 (333.8)	0.26†
Intraoperative blood loss^a (ml)	175.3 (83.7)	170.5 (80.9)	0.87†
Hidden blood loss^a ## (ml)	576.6 (229.3)	693.2 (302.9)	0.04†
Transfusion^b			0.99§
None	49 (96.1%)	48 (96%)
2 unit	0 (0.0%)	0 (0.0%)
4 units	2 (3.9%)	2 (4.0%)

^aThe values are given as the mean and the standard deviation
^bThe values are given as the number of patients, with the percentage in parentheses
†Significance was determined with use of Independent-Sample T test
§significance was determined with use of the Fisher exact test
# PBV (Patient’s blood volume) = k1 x height^3 (m) + k2 x weight (kg) + k3, where k1 = 0.3669, k2 = 0.03219, and k3 = 0.6041 for men; and k1 = 0.3561, k2 = 0.03308, and k3 = 0.1833 for women; Total blood loss = PBV x (preoperative Hct – postoperative Hct)
## Hidden blood loss = Total blood loss – Intraoperative blood loss + Allogeneic blood transfusion

ISSN: 1471-2474