Supplemental Table 2. PION Cases vs. Controls

Cases (n=9) / Controls (n=18) / p-value / Odds Ratio / 95% CI
Preoperative Variables
Age / 69.3±8.7 / 66.4±6.0 / NA / N/A
Body Mass Index a / 30.4±5.8 / 27.7±4.9 / 0.2198 / 1.114 / 0.937 / 1.325
Medical History
Diabetes / 4 (44%) / 2 (11%) / 0.0957 / 6.606 / 0.717 / 60.859
Smoking b / 6 (67%) / 5 (28%) / 0.1485 / 5.260 / 0.553 / 50.021
Hypertension / 7 (78%) / 6 (33%) / 0.0516 / 4.956 / 0.989 / 24.838
Coronary artery disease / 4 (44%) / 3 (17%) / 0.4292 / 2.732 / 0.226 / 33.003
Myocardial infarction / 2 (22%) / 0 (0%) / 0.7248 / 1.443 / 0.187 / 11.117
Stroke / 1 (11%) / 0 (0%) / 0.9963 / 28100817 / 0.000
Renal disease / 0 (0%) / 0 (0%) / NA / N/A
Hyperlipidemia / 3 (33%) / 7 (39%) / 0.7895 / 0.806 / 0.165 / 3.934
Mean Arterial Pressure c / 98.7±10.6 / 99.7±8.0 / 0.7561 / 0.985 / 0.895 / 1.084
Hematocrit / 39.1±4.4 / 42.3 ±4.1 / 0.0972 / 0.813 / 0.637 / 1.038
Disc-at-risk / 3/8 (38%) / 6/10 (60%) / 0.3106 / 0.295 / 0.028 / 3.120
Disc-at-risk with missing imputed as Yes / 4 ( 44.4) / 14 ( 77.8) / 0.1170 / 0.171 / 0.019 / 1.556
Disc-at-risk with missing imputed as No / 3 ( 33.3) / 6 ( 33.3) / 1.0000 / 1.000 / 0.183 / 5.460
Intraoperative Variables
Mean Arterial Pressure
Lowest
Change from pre-op
% Change from pre-op
Duration (in min) / 62.7±8.7
-35.9 ± 13.3
-35.8 ± 10.6
12.2 ± 12.0 / 60.8±9.7 (n=17)
-38.3 ± 11.5
-38.5 ± 10.1
6.2 ± 3.3 / 0.5195
0.5049
0.4072
0.9975 / 1.036
1.032
1.054
5.177 / 0.930
0.940
0.931
0.000 / 1.155
1.134
1.193
Hematocrit
Lowest
Change from pre-op
% Change from pre-op / 23.0 ± 7.1 (n=2)
-19.5 ± 0.4
-46.5 ± 8.3 / 20.8 ± 2.9 (n=4)
-17.1 ± 5.2
-44.6 ± 9.1 / 0.4863
0.5404
0.8078 / 1.361
0.867
0.977 / 0.572
0.549
0.809 / 3.237
1.369
1.180
Blood products administered / 3 patients (33%) / 5 patients (28%) / 0.7248 / 1.443 / 0.187 / 11.117
Blood Loss (cc) / 1050cc±1116 (n=6)
750(250,3250) / 991±1220 (n=11)
800(100,4500) / 0.8116 / 1.000 / 0.999 / 1.001
Lowest temperature / 31.5 ± 0.9 (n=2) / 30.2 ± 2.0 / 0.5510 / 2.342 / 0.143 / 38.418
Surgery Time (in hour) / 4.1 ± 2.0 / 4.2 ± 2.7 (n=4) / 0.7882 / 0.902 / 0.423 / 1.921
Vasopressors / 6 (66.67%) / 10 (55.56%) / 0.5315 / 1.823 / 0.278 / 11.953
Postoperative Variables
Mean Arterial Pressure
Lowest
Change from pre-op
% Change from pre-op
Duration (in min) / 66.2 ± 16.5
-32.5 ± 21.8
-31.9 ± 18.8
36.1 ± 34.9 / 71.4±11.6
-28.3 ± 12.9
-28.2 ± 12.1
31.4 ± 53.5 / 0.3783
0.5578
0.5616
0.8165 / 0.972
0.986
0.984
1.002 / 0.911
0.940
0.933
0.986 / 1.036
1.034
1.039
1.017
Hematocrit
Lowest
Change from pre-op
% Change from pre-op / 25.5 ± 4.2
-13.7 ± 6.2
-34.2 ± 12.5 / 29.5±5.9 (n=17)
-12.8 ± 5.3
-30.2 ± 11.6 / 0.0806
0.7539
0.4605 / 0.775
0.976
0.970 / 0.582
0.838
0.896 / 1.032
1.137
1.051
Blood products administered / 5 patients (55.6%) / 6 patients (33.3%) / 0.2635 / 2.732 / 0.469 / 15.908

a Body Mass Index = [weight in pounds/(height in inches)2] x 703

b Current or any prior history of smoking

c Mean arterial pressure = [(systolic blood pressure – diastolic blood pressure)/3 + diastolic blood pressure] (mmHg)

PION=Posterior ischemic optic neuropathy