Double‐Blind, Randomized, Placebo‐Controlled Evaluation of Atropine to Prevent Vasovagal Reaction During Removal of Femoral Arterial Sheaths

Study Objective . To evaluate the efficacy and safety of atropine in preventing vasovagal reactions (VVRs) during removal of femoral arterial sheaths after diagnostic left heart catheterization. Design . Prospective, double‐blind, randomized, placebo‐controlled study. Setting . University‐affiliated, 450‐bed teaching hospital. Patients . One hundred sixty‐five patients undergoing left heart catheterization. Interventions . Eighty‐eight patients were assigned to receive atropine 0.5 mg intravenously and 77 received placebo 5 minutes before sheath removal. Measurements and Main Results . The frequency of VVRs was significantly reduced in the atropine group compared with the placebo group, 2.3% and 10.4%, respectively (overall relative risk in the atropine group 0.22, 95% CI 0.12‐0.41, p=0.03). Significant decreases in systolic (35.2 ± 5.8 mm Hg, p<0.001) and diastolic blood pressures (12.6 ± 12.6 mm Hg, p=0.002) occurred in the 10 patients with VVRs compared with those without VVR. No cardiac arrhythmias occurred after atropine administration. Dry mouth was the only side effect reported with atropine (8/88, 9%). Conclusion . Atropine significantly reduced the frequency of VVRs associated with removal of femoral arterial sheaths after diagnostic left heart catheterization. The drug should be studied in a larger series of patients to assess its ability to decrease the morbidity and costs associated with VVR. (Pharmacotherapy 1997;17(5):867–873)