Adrenergic receptor genotype but not perioperative bisoprolol therapy may determine cardiovascular outcome in at-risk patients undergoing surgery with spinal block: the Swiss Beta Blocker in Spinal Anesthesia (BBSA) study: a double-blinded, placebo-controlled, multicenter trial with 1-year follow-up.
BACKGROUND
Neuraxial blockade is used as primary anesthetic technique in one third of surgical procedures. The authors tested whether bisoprolol would protect patients at risk for cardiovascular complications undergoing surgery with spinal block.


METHODS
The authors performed a double-blinded, placebo-controlled, multicenter trial to compare the effect of bisoprolol with that of placebo on 1-yr composite outcome including cardiovascular mortality, nonfatal myocardial infarction, unstable angina, congestive heart failure, and cerebrovascular insult. Bisoprolol was given orally before and after surgery for a maximum of 10 days. Adrenergic receptor polymorphisms and safety outcome measures of bisoprolol therapy were also determined.


RESULTS
A total of 224 patients were enrolled. Spinal block could not be established in 5 patients. One hundred ten patients were assigned to the bisoprolol group, and 109 patients were assigned to the placebo group. The mean duration of treatment was 4.9 days in the bisoprolol group and 5.1 days in the placebo group. Bisoprolol therapy reduced mean heart rate by 10 beats/min. The primary outcome was identical between treatment groups and occurred in 25 patients (22.7%) in the bisoprolol group and 24 patients (22.0%) in the placebo group during the 1-yr follow-up (hazard ratio, 0.97; 95% confidence interval, 0.55-1.69; P = 0.90). However, carriers of at least one Gly allele of the beta1-adrenergic receptor polymorphism Arg389Gly showed a higher number of adverse events than Arg homozygous (32.4% vs. 18.7%; hazard ratio, 1.87; 95% confidence interval, 1.04-3.35; P = 0.04).


CONCLUSIONS
Perioperative bisoprolol therapy did not affect cardiovascular outcome in these elderly at-risk patients undergoing surgery with spinal block.
Zaugg
Michael
M
Institute of Anesthesiology, University Hospital Zurich, Zurich, Switzerland. michael.zaugg@usz.ch
Bestmann
Lukas
L
Wacker
Johannes
J
Lucchinetti
Eliana
E
Boltres
Anita
A
Schulz
Christian
C
Hersberger
Martin
M
Kälin
Gabriela
G
Furrer
Lukas
L
Hofer
Christoph
C
Blumenthal
Stephan
S
Müller
Annabelle
A
Zollinger
Andreas
A
Spahn
Donat R
DR
Borgeat
Alain
A
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000775:Anesthesia, Spinal; D017298:Bisoprolol / Q000627:therapeutic use*; D002311:Cardiomyopathy, Dilated / Q000401:mortality / Q000517:prevention & control; D002318:Cardiovascular Diseases / Q000401:mortality / Q000517:prevention & control*; D003327:Coronary Disease / Q000401:mortality / Q000517:prevention & control; D004311:Double-Blind Method; D015716:Electrocardiography, Ambulatory; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D007431:Intraoperative Complications / Q000401:mortality / Q000517:prevention & control*; D009203:Myocardial Infarction / Q000401:mortality / Q000517:prevention & control; D011183:Postoperative Complications / Q000401:mortality / Q000517:prevention & control*; D016016:Proportional Hazards Models; D011941:Receptors, Adrenergic / Q000235:genetics*; D012129:Respiratory Function Tests; D012306:Risk; D013557:Switzerland; D016896:Treatment Outcome
D000319:Adrenergic beta-Antagonists; D011941:Receptors, Adrenergic; D017298:Bisoprolol