Outpatient cardiac catheterisation.

Cardiac catheterisation is increasingly performed in an outpatient setting. The majority of series of outpatient cardiac catheterisation are in laboratories with immediate access to cardiovascular surgery. However, some units may be sited more distantly, although still generally close to a hospital. Compared to an inpatient procedure, outpatient cardiac catheterisation increases bed availability and there are considerable financial rewards with suggested savings of 11-54% of inpatient costs. Most patients are satisfied with an outpatient procedure and, although a quarter may have unanswered questions afterwards, this level may not differ from that found with inpatients. No study has been large enough to detect differences in the major complication rate which occur infrequently in whichever setting, and there is considerable variation between studies in the incidence of minor complications after outpatient procedures. In the only study which randomised all eligible patients to an inpatient (189 patients) or outpatient (192 patients) procedure, seven outpatients (3.6%) suffered bleeding or developed haematomas at the site of percutaneous femoral artery puncture towards the end of the mobilisation period and one patient was syncopal. These events were thought to be a direct result of the procedure being carried out in the outpatient setting. The proportion of patients considered eligible for outpatient cardiac catheterisation varies widely between different series from 20% to more than 80%. Whereas some of this variation may result from the implementation of different exclusion criteria for patients with potentially severe disease, the differences are so large that it is likely that different populations were studied. Unplanned admission rates varied from less than 1% to nearly 19%. With the currently available data no absolute guidelines can be derived to exclude all patients at risk of complications, but the American College of Cardiology/American Heart Association (ACC/AHA) task force recently published guidelines which identified low risk patients suitable for outpatient procedures. These guidelines have been used to select patients for investigation in two mobile units in the USA, and only 0.9% required urgent transfer for clinical instability, and 0.6% developed major complications. However, most patients did not need referral to a tertiary centre for additional procedures and there may be less scope for selecting patients within the ACC/AHA guidelines in the UK compared with the USA.