Postoperative Packing of Perianal Abscess Cavities (PPAC2): randomized clinical trial
Katy Newton, Jo C Dumville, Michelle Briggs, Jennifer Law, Julia Martı́n, Lyndsay Pearce, Cliona Kirwan, Thomas Pinkney, A. Needham, Richard F. W. Jackson, Simon Winn, Haley McCulloch, James Hill, PPAC2 Collaborators, Andrew Watson, Matthew W. Johnson, Louise Hiller, Eftychia Eirini Psarelli, Louise Murray, Ashley Smith, Steven R. Brown, Bhagirath Singh, C. Newby, O Ali, Anisha Sukha, Natalie Blencowe, Sunil K. Narang, Nicola Reeves, G Faulkner, Shivakumar Rajamanickam, Jackie Evans, S Mangam, M Harilingham, Christopher J. Smart, S J Ward, M Bogdan, Kavit Amin, Ziad Al-Khaddar, Elizabeth Davies, Prashant Patel, Adam T. Stearns, Iman Shaik, James Hernon, Anirban Pal, M. Lewis, J.A. Barker, A. Gerrard, Mostafa Abdel-Halim, Paul Shuttleworth, Matthew J. Lee, Adam Peckham-Cooper, Adam Hague, C Challand, Christopher J. Steele, Nicola Fearnhead, Stijn van Laarhoven, R Brady, Fadlo Shaban, Newton A C S Wong, WC Ngu, G. Williams, R. J. Codd, D Magowan, Kai’En Leong, G. Williams, Andrew Torrance, Balamurali Bharathan, Nikhil Pawa, Harmehr Sekhon, Isha Singh, A Alabi, David Berry, Vasileios Trompetas, John Hughes, Raimundas Lunevičius, Raimundas Lunevičius, Karely Mann, Steven Dixon, T Ingram, Timothy Gilbert, C Brooks, G Madzamba, Anne Pullyblank, George Dovell, Laura Newton, N Carter, Peter May-Miller, Shafaque Shaikh, Rosalyn Shearer, Colin Macleod, C. N. Parnaby, A Abdelmabod, L Titu, Talib A. Majeed, Rachel Hargest, Jim Parker, Catherine Zabkiewicz, Nicola Reeves, Faris Soliman, Gemma Gossedge
Abstract
BACKGROUND: Perianal abscess is common. Traditionally, postoperative perianal abscess cavities are managed with internal wound packing, a practice not supported by evidence. The aim of this randomized clinical trial (RCT) was to assess if non-packing is less painful and if it is associated with adverse outcomes. METHODS: The Postoperative Packing of Perianal Abscess Cavities (PPAC2) trial was a multicentre, RCT (two-group parallel design) of adult participants admitted to an NHS hospital for incision and drainage of a primary perianal abscess. Participants were randomized 1:1 (via an online system) to receive continued postoperative wound packing or non-packing. Blinded data were collected via symptom diaries, telephone, and clinics over 6 months. The objective was to determine whether non-packing of perianal abscess cavities is less painful than packing, without an increase in perianal fistula or abscess recurrence. The primary outcome was pain (mean maximum pain score on a 100-point visual analogue scale). RESULTS: Between February 2018 and March 2020, 433 participants (mean age 42 years) were randomized across 50 sites. Two hundred and thirteen participants allocated to packing reported higher pain scores than 220 allocated to non-packing (38.2 versus 28.2, mean difference 9.9; P < 0.0001). The occurrence of fistula-in-ano was low in both groups: 32/213 (15 per cent) in the packing group and 24/220 (11 per cent) in the non-packing group (OR 0.69, 95 per cent c.i. 0.39 to 1.22; P = 0.20). The proportion of patients with abscess recurrence was also low: 13/223 (6 per cent) in the non-packing group and 7/213 (3 per cent) in the packing group (OR 1.85, 95 per cent c.i. 0.72 to 4.73; P = 0.20). CONCLUSION: Avoiding abscess cavity packing is less painful without a negative morbidity risk. REGISTRATION NUMBER: ISRCTN93273484 (https://www.isrctn.com/ISRCTN93273484). REGISTRATION NUMBER: NCT03315169 (http://clinicaltrials.gov).