Clinical trial NCT01358422: Occurrence of Bleeding and Thrombosis During Antiplatelet Therapy in Non-cardiac Surgery
Official title: Occurrence of Bleeding and Thrombosis During Antiplatelet Therapy in Non-cardiac Surgery. A Prospective Observational Study (OBTAIN Study)
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Bleeding
Thrombosis
Cardiac Events
Keywords: Prospective observational study
major adverse cardiac events (MACE)
clinically significant bleeding events
Dual anti-platelet therapy
aspirin alone therapy
non-cardiac surgery
percutaneous coronary intervention (PCI)
placement of a bare metal or drug eluting stent
OBTAIN
Simon Howell
ESA
European Society of Anaesthesiology
Lead sponsor: European Society of Anaesthesiology
Sponsor class: OTHER
Collaborators: name: University of Leeds
name: Erasmus Medical Center
First posted: 2011-05-23
Enrollment: 830
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Patients undergoing non-cardiac surgery within four years of percutaneous coronary intervention (PCI) with the placement of a bare metal or drug eluting stent will be included in the study.

Brief summary: Research questions:

1. What is the absolute risk reduction for in-hospital major adverse cardiac events (MACE) associated with the use of dual anti-platelet therapy as compared with aspirin alone in this population?
2. What is the absolute risk increase for clinically significant bleeding during the same period associated with the use of dual anti-platelet therapy as compared with aspirin alone in this population?

In brief the design of the study is as follows:

* We will study patients undergoing non-cardiac surgery within four years of coronary stenting.
* We will record the anti-platelet agents taken by patients before, during and after surgery.
* We will record cardiac and bleeding events that occur whilst the patient is in hospital.
* We will use the statistical technique of propensity scoring to match patients who have similar risk factors and who received different anti-platelet regimens.
* We will compare the incidence of cardiac events and bleeding in the matched groups.

Detailed description: This study will compare the use of aspirin alone with dual antiplatelet therapy (i.e. aspirin and clopidogrel) in patients presenting for elective non-cardiac surgery who have undergone PCI with either bare metal stent or drug eluting stent placement in the four years prior to surgery. The absolute risk reduction in major adverse cardiac events (MACE) with dual antiplatelet therapy and the absolute risk increase for clinically significant bleeding events with dual therapy will be determined. This will allow the number needed to treat (NNT) for the prevention of MACE and the number needed to harm (NNH) for bleeding to be determined and the optimal antiplatelet therapy in this setting to be identified.

Eligibility criteria: Inclusion Criteria:

* Patients undergoing non-cardiac surgery within four years of percutaneous coronary intervention (PCI) with the placement of a bare metal or drug eluting stent will be included in the study.

Exclusion Criteria:

* Patients maintained on anticoagulant therapy e.g. heparin infusion before and after surgery will be excluded. (Patients receiving prophylactic doses of heparin for prevention of thromboembolic events will be eligible for inclusion.)
* Patients receiving bridging therapy with full anticoagulant does of heparin or other drugs to compensate for the withdrawal of antiplatelet drugs will be excluded.
* Patients who are anticoagulated with warfarin (INR\>1.5 at the time of surgery) will be excluded.
* Patients receiving full anticoagulation with heparin for a known recent a known thromboembolic event (APPT ratio \> 1.5) be excluded. -

Primary outcomes:
measure: 1. MACE
timeFrame: In-hospital stay up to 30 days
measure: 2. Clinically significant bleeding
timeFrame: In-hospital stay up to 30 days
Secondary outcomes:
Other outcomes:
Locations:
city: Dresden
country: Germany
facility: University Hospital Carl Gustav Carus
city: Rotterdam
country: Netherlands
facility: Erasmus University
city: Leeds
country: United Kingdom
facility: University of Leeds, Sectional of Translational Anaesthetic and Surgical Sciences
Study officials:
affiliation: Sectional of Translational Anaesthetic and Surgical Sciences, University of Leeds, United Kingdom
name: Simon Howell, MD
role: STUDY_CHAIR
References:
citation: Howell SJ, Hoeks SE, Poldermans D, West RM, Wheatcroft SB. OBTAIN: a study of the occurrence of bleeding and thrombosis during anti-platelet therapy in non-cardiac surgery. Eur J Anaesthesiol. 2011 Jun;28(6):456-9. doi: 10.1097/EJA.0b013e328344b4fc. No abstract available.