Nomogram of Wang et al for Predicting Blood Transfusion After Hemiarthroplasty for a Femoral Neck Fracture

Patient selection: status post hemiarthroplasty for femoral neck fracture in an older adult

Indications for blood transfusion - one of the following:

(1) hemoglobin less than 80 g/L

(2) hemoglobin less than 100 g/L AND (unstable vital signs OR symptoms)

Parameters:

(1) time to surgery in days, from 1 to 10 days

(2) preoperative hemoglobin in g/L, from 90 to 160 g/L

(3) type of anesthesia

(4) duration of surgery in minutes, from 30 to 130 minutes

(5) intraoperative blood loss in mL, from 50 to 400 mL

points for time to surgery =

= (6.544 * (time)) - 6.544

points for preoperative hemoglobin =

= 228.57 - (1.42857 * (hemoglobin))

points for duration of surgery =

= (0.647 * (duration)) - 19.41

points for intraoperative blood loss =

= (0.0826 * (blood loss)) - 4.1286

total score =

= SUM(points for all of the parameters)

Interpretation:

• minimum score: 0

• maximum score: 267.3

• The higher the score the greater the chances of blood transfusion.

value of X =

= (0.102 * (score)) - 17.09

Performance:

• The area under the ROC curve is 0.94.