Perioperative blood product administration and thromboembolic events in patients with treated polycythemia vera: a case-control study.
BACKGROUND
Patients with polycythemia vera (PV) have historically been considered to be at high risk for perioperative hemorrhagic and thromboembolic complications. However, no recent studies have compared these outcomes between treated PV patients and patients without PV undergoing similar procedures.


METHODS
Patients with PV who underwent surgery with anesthesia from June 1, 2006, to May 31, 2011, were randomly matched (sex, age, type of surgical procedure, surgical year) at a ratio of 1:4 with control patients without PV. Conditional logistic regression analysis adjusting for surgical duration, preoperative hemoglobin, platelet count, and cardiovascular disease was used to assess the association between PV and blood product transfusions, thromboembolism, and other major cardiovascular and pulmonary complications.


RESULTS
Fifty-six PV patients who underwent 79 surgeries were matched with 312 controls. During hospitalization, 35 (44.3%) and 82 (25.9%) PV and control patients, respectively, were transfused with blood products. PV patients were at increased risk for transfusion intraoperatively (odds ratio [OR], 4.35; 95% confidence interval [CI], 1.79-10.57; p = 0.001) and during hospitalization (OR, 4.35; 95% CI, 1.84-10.31; p < 0.001). The likelihood of thromboembolic complications and/or other major complications did not differ between the two study groups (thromboembolic-OR 1.53, 95% CI 0.39-6.02, p = 0.540; other major complications-OR 2.15, 95% CI 0.93-4.96, p = 0.073).


CONCLUSIONS
Medically managed PV patients had an increased likelihood of receiving blood products perioperatively. Given the low number of observed thromboembolic events, we cannot make definitive conclusions regarding the association between PV and thromboembolism.
Department of Anesthesiology.
Toby N
TN
Weingarten
Department of Anesthesiology.
Ryan E
RE
Hofer
Department of Anesthesiology.
Barrett J
BJ
Ahle
Department of Anesthesiology.
Keri M
KM
Kemp
Department of Anesthesiology.
Jacinta A
JA
Nkwonta
Department of Anesthesiology.
Bradly J
BJ
Narr
Division of Hematology.
Animesh
A
Pardanani
Division of Biomedical Statistics and Informatics and Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota.
Darrell R
DR
Schroeder
Department of Anesthesiology.
Juraj
J
Sprung
D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011087:Polycythemia Vera / Q000601:surgery* / Q000628:therapy; D012189:Retrospective Studies; D013923:Thromboembolism / Q000209:etiology*; D065227:Transfusion Reaction