From: Predictors of intra-operative blood loss and blood transfusion in orthognathic surgery: a retrospective cohort study in 92 patients
Length of surgery
N
Mean
SD
P-value
1-3 hrs.
15
316.67
206.73
>3-6 hrs.
36
713.89
435.17
>6-10 hrs.
41
715.85
359.94
0.001*
Total
92
650.00
397.80