Ambulatory surgery

In the past few decades, the number of surgical procedures carried out on a same-day basis has markedly increased in OECD countries. Advances in medical technologies – in particular the diffusion of less invasive surgical interventions – and better anaesthetics have made this development possible. These innovations have improved patient safety and health outcomes. Further, by shortening the treatment episode, ambulatory surgery can save important resources without any adverse effects on quality of care. It also frees up capacity within hospitals to focus on more complex cases or to reduce waiting lists. However, the impact of the rise in same-day surgery on overall health spending may not be straightforward, since the reduction in unit costs (compared to inpatient surgery) may be offset by overall growth in the volume of procedures performed. Any additional costs related to post-acute care and community health services following the interventions also need to be considered.

Cataract surgeries and tonsillectomies (the removal of tonsils – glands at the back of the throat – mainly performed on children) provide good examples of high-volume surgeries that are now mainly carried out on a same-day basis in many OECD countries.

Ambulatory surgery accounts for 90% or more of all cataract surgeries in the majority of OECD countries (Figure 5.29). In several countries, nearly all cataract surgeries are performed as day cases; however, the rate is low in Lithuania, Hungary and Mexico, with fewer than 65% of surgeries performed as ambulatory cases. While this may be explained in part by limitations in the data coverage of outpatient activities in or outside hospitals, it may also reflect higher reimbursement for inpatient stays or constraints on the development of day surgery.

Tonsillectomies are one of the most frequent surgical procedures performed on children – usually those suffering from repeated or chronic infections of the tonsils, breathing problems or obstructive sleep apnoea due to large tonsils. Although the operation is performed under general anaesthesia, it is now carried out predominantly as ambulatory surgery in 11 of 30 OECD countries with comparable data, with children returning home the same day (Figure 5.30). However, the proportion of day cases is not as high as for cataract surgery, at 38% of tonsillectomies versus 92% of cataract surgeries on average across OECD countries. Day tonsillectomy rates are relatively high in Iceland, Finland and Costa Rica (85% of cases or higher) but remain lower than 10% of cases in nine OECD countries. In Slovenia, Hungary, the Czech Republic and Austria, practically no tonsillectomies are undertaken as day cases. These large differences in the share of ambulatory surgery may reflect variations in the perceived risks of postoperative complications, or simply clinical traditions of keeping children in hospital for at least one night after the operation.

The number of cataract surgeries and tonsillectomies performed as ambulatory cases has grown significantly since 2009 in many countries, including Austria, France and the United Kingdom (Figure 5.31 and Figure 5.32). In Austria, the share of cataract surgeries performed as day cases increased from only 24% in 2009 to 88% in 2019; in Lithuania, it increased from 8% to 52%. The share of tonsillectomies performed as ambulatory cases doubled between 2009 and 2019 in Sweden (39% to 79%) and the United Kingdom (31% to 63%). By minimising the time spent in hospital settings, same-day surgeries also reduce the risk of exposure to COVID-19. Initial data for 2020 show only slight changes in the share of cataract surgeries or tonsillectomies performed on an ambulatory basis.

Financial incentives can also affect the extent to which minor surgery is conducted on a same-day basis. In Denmark and France, diagnostic-related group systems have been adjusted to incentivise ambulatory surgery. In the United Kingdom, a financial incentive of approximately GBP 300 per case is awarded for selected surgical procedures if the patient is managed on a day-case basis (OECD, 2017[19]).

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