Introduction

Tonsillectomy is a common operation performed largely on children.Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹ The principal indications are recurrent bacterial tonsillitis, peritonsillar abscess (quinsy) and obstructive sleep apnoea.Reference Stuck, Gotte, Windfuhr, Genzwurker, Schroten and Tenenbaum ² For these indications, tonsillectomy has been shown to significantly improve patient outcomes, thereby demonstrating its clinical value.Reference Konieczny, Biggs and Caldera ³ In practice, extensive clinical experience is required to determine which individuals should be offered surgery because of difficulties interpreting child and parental complaints. Tonsillectomy is almost entirely performed as an elective procedure.Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹

Tonsillectomy is a low-risk procedure.Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹ Most complications are not serious; they include excessive pain, vomiting, odynophagia and fever. Post-tonsillectomy haemorrhage remains the most serious complication, which can occur at any time in any patient, and has the potential to be life-threatening. A recent Swedish study identified the mortality rate associated with post-tonsillectomy haemorrhage as 1 in 41 000.Reference Ostvoll, Sunnergren, Ericsson, Hemlin, Hultcrantz and Odhagen ⁴ Post-operative haemorrhage is classified as primary (occurring less than 24 hours after the procedure) or secondary (occurring more than 24 hours after surgery). The causation of primary haemorrhage is widely accepted to be suboptimal surgical technique.

The rate of post-tonsillectomy haemorrhage reported in the literature is highly variable. This variation arises because of differences in: the study patient population, the length of post-operative observation and the definition of ‘post-operative haemorrhage’.Reference Stuck, Gotte, Windfuhr, Genzwurker, Schroten and Tenenbaum ^{2 ,} Reference Windfuhr, Verspohl, Chen, Dahm and Werner ⁵ The UK post-tonsillectomy haemorrhage rate in 2003–2004 was 3.5 per cent (n = 33 921; primary = 0.6 per cent, secondary = 2.9 per cent), with 0.9 per cent of affected patients returning to the operating theatre.Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹ In 2003–2004, the most commonly used technique in the UK was cold-steel with bipolar haemostasis (35 per cent; overall rate of post-tonsillectomy haemorrhage = 2.7 per cent), followed by bipolar forceps (30 per cent; haemorrhage = 4.6 per cent), cold-steel with ties (13 per cent; haemorrhage = 1.7 per cent), and coblation (5 per cent; haemorrhage = 4.6 per cent).Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹

Several risk factors have been suggested for post-tonsillectomy haemorrhage. The National Prospective Tonsillectomy Audit (2005) identified an increased risk of post-tonsillectomy haemorrhage with increasing patient age, male gender and with single-use instruments.Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹ Other studies have identified known coagulopathy and increasing operative time as risk factors.Reference Stuck, Gotte, Windfuhr, Genzwurker, Schroten and Tenenbaum ^{2 ,} Reference Windfuhr, Verspohl, Chen, Dahm and Werner ⁵ The tonsillectomy technique used has been suggested as a risk factor by many studies; however, the findings of a recent Cochrane review were inconclusive.Reference Windfuhr, Verspohl, Chen, Dahm and Werner ^{5 –} Reference Mosges, Hellmich, Allekotte, Albrecht and Bohm ⁷ The National Prospective Tonsillectomy Audit found that ‘hot’ (bipolar or coblation) techniques were associated with a greater risk of haemorrhage than cold-steel with ties, although only the coblation technique was associated with a statistically significant elevated risk of returning to the operating theatre.Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹ The National Prospective Tonsillectomy Audit found no statistically significant relationship between the grade of a surgeon and risk of haemorrhage.Reference Brown, Ryan, Yung, Browne, Copley and Cromwell ¹

As coagulopathy is a potentially modifiable risk factor for post-tonsillectomy haemorrhage, it is often speculated whether all patients should be investigated. Stuck et al. suggest that to detect coagulation disorders, a focused history is of greater benefit than routine coagulation testing.Reference Stuck, Gotte, Windfuhr, Genzwurker, Schroten and Tenenbaum ^{2 ,} Reference Koscielny, Ziemer, Radtke, Schmutzler, Pruss and Sinha ⁸ Therefore, if there is no suggestion in the history, routine coagulation screening is not indicated.Reference Stuck, Gotte, Windfuhr, Genzwurker, Schroten and Tenenbaum ²

All patients are at risk of unsafe medical practices and care during procedures in hospital. Multiple studies have identified an increased mortality risk for medical and surgical emergency weekend admissions compared with weekday admissions.Reference Aylin, Yunus, Bottle, Majeed and Bell ^{9 ,} Reference Aylin, Alexandrescu, Jen, Mayer and Bottle ¹⁰ This has been attributed to reduced staffing and service availability at the weekend, in combination with ‘sicker weekend patients’. Mohammed et al. reported weekend admission to be an independent risk factor for in-patient death; the risk was more pronounced in the elective setting.Reference Mohammed, Sidhu, Rudge and Stevens ¹¹ Further research has identified increased 30-day mortality rates for elective surgery carried out closer to the end of the week and during the weekend itself.Reference Aylin, Alexandrescu, Jen, Mayer and Bottle ¹⁰ It is important to note that other studies have found no such effect.Reference Becker ^{12 –} Reference Roberts, Thorne, Akbari, Samuel and Williams ¹⁴ In addition to investigating high-risk procedures within general surgery and cardiothoracic surgery, Aylin et al. also analysed mortality for low-risk procedures including tonsillectomy.Reference Aylin, Alexandrescu, Jen, Mayer and Bottle ¹⁰ The authors found higher mortality rates for low-risk procedures carried out on a Friday compared with those conducted on a Monday, but there was no significant difference for procedures performed at the weekend.

Our aim was to investigate whether the findings of these studies had any relevance within otolaryngology, using tonsillectomy as the chosen procedure. It is inadequate to use mortality rate as an outcome in low-risk procedures such as tonsillectomy. The occurrence of complications such as post-tonsillectomy haemorrhage may provide a better indicator of altered patient care and is more relevant to everyday practice.

With increasing pressure for National Health Service trusts to meet government waiting-time targets, the number of elective surgical procedures performed at the weekend has increased. ¹⁵ There is a danger of having too many cases on these additional surgery schedules, which introduces further time pressure. As some studies have indicated an increased mortality risk in patients who undergo elective surgical procedures at the weekend, we hypothesised that post-tonsillectomy haemorrhage rates would increase for patients undergoing surgery at the weekend.Reference Aylin, Alexandrescu, Jen, Mayer and Bottle ¹⁰ The rationale for this is poorer quality of care at the weekend as a result of reduced staffing levels and less senior or experienced staff.