Early versus delayed appendicectomy for appendiceal phlegmon or abscess

Appendiceal phlegmon and abscess account for 2% to 10% of acute appendicitis. People with appendiceal phlegmon or abscess usually need an appendicectomy to relieve their symptoms and avoid complications. The timing of appendicectomy for appendiceal phlegmon or abscess is controversial.

To assess the effects of early versus delayed appendicectomy for appendiceal phlegmon or abscess, in terms of overall morbidity and mortality.

We searched the Cochrane Library (CENTRAL; 2016, Issue 7), MEDLINE Ovid (1950 to 23 August 2016), Embase Ovid (1974 to 23 August 2016), Science Citation Index Expanded (1900 to 23 August 2016), and the Chinese Biomedical Literature Database (CBM) (1978 to 23 August 2016). We also searched the World Health Organization (WHO) International Clinical Trials Registry Platform search portal (23 August 2016) and ClinicalTrials.gov (23 August 2016) for ongoing trials.

We included all individual and cluster-randomised controlled trials, irrespective of language, publication status, or age of participants, comparing early versus delayed appendicectomy in people with appendiceal phlegmon or abscess.

Two review authors independently identified the trials for inclusion, collected the data, and assessed the risk of bias. We performed meta-analyses using Review Manager 5. We calculated the risk ratio (RR) for dichotomous outcomes and the mean difference (MD) for continuous outcomes with 95% confidence intervals (CI).

We included two randomised controlled trials with a total of 80 participants in this review. 1. Early versus delayed open appendicectomy for appendiceal phlegmonForty participants (paediatric and adults) with appendiceal phlegmon were randomised either to early appendicectomy (appendicectomy as soon as appendiceal mass resolved within the same admission) (n = 20), or to delayed appendicectomy (initial conservative treatment followed by interval appendicectomy six weeks later) (n = 20). The trial was at high risk of bias. There was no mortality in either group. There is insufficient evidence to determine the effect of using either early or delayed open appendicectomy onoverall morbidity (RR 13.00; 95% CI 0.78 to 216.39; very low-quality evidence), the proportion of participants who developed wound infection (RR 9.00; 95% CI 0.52 to 156.91; very low quality evidence) or faecal fistula (RR 3.00; 95% CI 0.13 to 69.52; very low quality evidence). The quality of evidence for increased length of hospital stay and time away from normal activities in the early appendicectomy group (MD 6.70 days; 95% CI 2.76 to 10.64, and MD 5.00 days; 95% CI 1.52 to 8.48, respectively) is very low quality evidence. The trial reported neither quality of life nor pain outcomes. 2. Early versus delayed laparoscopic appendicectomy for appendiceal abscessForty paediatric participants with appendiceal abscess were randomised either to early appendicectomy (emergent laparoscopic appendicectomy) (n = 20) or to delayed appendicectomy (initial conservative treatment followed by interval laparoscopic appendicectomy 10 weeks later) (n = 20). The trial was at high risk of bias. The trial did not report on overall morbidity or complications. There was no mortality in either group. We do not have sufficient evidence to determine the effects of using either early or delayed laparoscopic appendicectomy for outcomes relating to hospital stay between the groups (MD -0.20 days; 95% CI -3.54 to 3.14; very low quality of evidence). Health-related quality of life was measured with the Pediatric Quality of Life Scale-Version 4.0 questionnaire (a scale of 0 to 100 with higher values indicating a better quality of life). Health-related quality of life score measured at 12 weeks after appendicectomy was higher in the early appendicectomy group than in the delayed appendicectomy group (MD 12.40 points; 95% CI 9.78 to 15.02) but the quality of evidence was very low. This trial reported neither the pain nor the time away from normal activities.

It is unclear whether early appendicectomy prevents complications compared to delayed appendicectomy for people with appendiceal phlegmon or abscess. The evidence indicating increased length of hospital stay and time away from normal activities in people with early open appendicectomy is of very low quality. The evidence for better health-related quality of life following early laparoscopic appendicectomy compared with delayed appendicectomy is based on very low quality evidence. For both comparisons addressed in this review, data are sparse, and we cannot rule out significant benefits or harms of early versus delayed appendicectomy.Further trials on this topic are urgently needed and should specify a set of criteria for use of antibiotics, percutaneous drainage of the appendiceal abscess prior to surgery and resolution of the appendiceal phlegmon or abscess. Future trials should include outcomes such as time away from normal activities, quality of life and the length of hospital stay.