Low Body Mass Index and Blood Loss in Primary Total Hip Arthroplasty: Results from 236 Consecutive Ankylosing Spondylitis Patients

Table 3

Intraoperative data, blood loss, and transfusion.

	Underweight group	Normal weight group	𝑃
Operating time (min)*	60 (11)	61 (8)	0.984
Diameter of acetabular cup (mm)*	52.0 (2.2)	52.4 (2.0)	0.092
Intrablood loss/BV (%)*	10 (1)	10 (2)	0.277
Hidden blood loss/BV (%)*	15 (1)	13 (3)	<0.001
CTBL/BV (%)*	25 (2)	23 (4)	<0.001
Transfusion rate	75/91	98/145	0.012^†
RBCs transfused (U)*	1.9 (0.2)	2.0 (0.1)	0.235
Length of external wound compression time (h)	35 (7)	43 (6)	<0.001

∗Mean (SD). ^†Chi-square test. CTBL: calculated total blood loss; BV: blood volume; RBC: red blood cell.