The impact of out-of-hours elective surgery: is it worth the risk?

Abstract

We read with great interest the systematic review by Meewisse et al. on the effect of time of day on outcomes in elective surgery [1]. They postulate that timing of elective surgery could affect clinical outcome due to diurnal rhythms of patient physiology as well as surgical team performance. They found that evening/night-time elective surgery is associated with a higher risk of mortality compared with daytime surgery. While this seems intuitive, it is a topic lacking robust evidence at present.

With wait times for elective surgeries rising worldwide, as well as an ageing and increasingly more medically complex population, concerns surrounding patient safety with out-of-hours elective surgeries are high. This issue is of particular relevance in standalone obstetrics and gynaecology hospitals like ours, The National Maternity Hospital in Dublin, where elective surgeries are sometimes postponed to the evening due to emergency obstetric procedures occurring throughout the day. While the proportion of elective work in our hospital undertaken out-of-hours is low (approximately 1%), it is a common theme in obstetric hospitals.

The recently published 7th National Audit Project (NAP7) noted that, regarding elective surgeries, gynaecology was one of the most overrepresented surgical specialities with incidences of potentially serious complications and peri-operative cardiac arrest [2].

Meewisse et al. suggest ‘surgeon fatigue’ as a potential cause of increased morbidity/mortality with evening and night-time elective surgery [1]. However, we believe that fatigue affecting the entire operating theatre team is a more accurate risk factor. This coupled with reduced staffing levels and a lack of consultant anaesthetist presence that is commonplace in the evening and at night, may additionally contribute to increased out-of-hours morbidity and mortality. In fact, the NAP7 report mentions this point.

Additionally, adverse airway incidents leading to cardiac arrest in NAP7 were found to occur disproportionately out of hours, with 36% taking place at weekends, or in the evening or night-time hours [2]. While most elective caesarean section procedures are facilitated with neuraxial anaesthesia, it is estimated that a difficult airway is eight times more likely to be encountered in a pregnant than non-pregnant patient, should a general anaesthetic be necessary [3].

We were particularly interested to read about the diurnal variation in platelets and clotting factor activation and how this could be applied to improve patient outcomes. This is of particular relevance to our obstetrics and gynaecology specialist hospital which is the national referral centre for placenta accreta spectrum in Ireland. Perhaps in the future we will see more customised timing of surgical procedures with higher bleeding risks.

Meewisse et al. acknowledge that the quality of evidence included in their systematic review is low, but recent findings from NAP7 would support their theory that outcomes in out-of-hour surgeries are worse.

We agree that further investigation of this topic in the form of a well-designed, prospective study may provide a better understanding of the influence of timing of elective surgery on postoperative outcomes. This is an important topic that will provide clarity surrounding this issue in healthcare systems struggling with capacity and inadequate staffing levels. We see this as a modifiable risk factor which can and should be addressed.