Preoperative Plasmapheresis for Elective Thymectomy in Myasthenia Patient: Is It Necessary?
Table 1
Characteristics of patients between both groups.
Characteristics
Preoperative with plasmapheresis group (PPG) (33)
Preoperative without plasmapheresis group (NPPG) (53)
value
Male, (%)
8 (24.2)
17 (32.1)
0.475
Age (years), (mean ± SD)
44.2 ± 11.6
44.0 ± 15.3
0.933
Underlying disease (DM or HT or dyslipidemia)
17 (51.5)
30 (56.6)
0.663
Osserman classification
0.611
I
2 (6.1)
5 (9.4)
0.703
IIA
6 (18.2)
14 (26.4)
0.440
IIB
21 (63.6)
31 (58.5)
0.658
III
4 (12.1)
3 (5.7)
0.421
History of myasthenic crisis at any time
16 (48.5)
12 (22.6)
0.018
History of myasthenic crisis within one month before surgery
7 (21.2)
1 (1.9)
0.005
History of plasmapheresis within one month before surgery
11 (33.3)
5 (9.4)
0.009
Ocular involvement
15 (45.5)
25 (47.2)
1.000
Neck muscle motor power (mean ± SD)
4.5 ± 0.7
4.8 ± 0.4
0.025
Upper extremities motor power (mean ± SD)
4.4 ± 0.7
4.7 ± 0.5
0.009
lower extremities motor power (mean ± SD)
4.3 ± 0.8
4.7 ± 0.5
0.004
Respiratory involvement
6 (18.2)
1 (1.9)
0.012
Bulbar involvement
13 (39.4)
6 (11.3)
0.003
Mestinon use
33 (100)
47 (88.7)
0.078
Dose of mestinon (mg/day) (mean ± SD)
238.2 ± 132.0
204.9 ± 88.1
0.179
Prednisolone use
30 (91.0)
48 (91.0)
1.000
Dose of prednisolone (mg/day) (mean ± SD)
36.0 ± 19.8
29.3 ± 14.9
0.094
Azathioprine use
16 (48.5)
21 (39.6)
0.503
Dose of Azathioprine (mg/day) (mean ± SD)
65.6 ± 22.1
73.8 ± 28.0
0.342
FVC (mean ± SD)
1503.3 ± 304.7
2552.9 ± 221.5
0.019
Probability of receiving treatment (propensity score)*
0.53 ± 0.32
0.26 ± 0.15
<0.001
DM: diabetic mellitus, HT: hypertension, FVC: functional vital capacity.
*Propensity score calculated by logistic regression analysis considering gender, age, underlying disease, Osserman classification, history of myasthenic crisis at any time and within one month before surgery, ocular involvement, neck muscle, upper and lower extremities motor power, respiratory involvement, bulbar involvement, drug used, and FVC as determinants of receiving preoperative plasmapheresis.
