10.18 Complicated Appendicitis: Are Extended Antibiotics Necessary? A Post-hoc Analysis of the EAST MUSTANG Study

Posted on January 31, 2019

S. Bou Zein Eddine1, C. M. Dodgion1, C. Trevino1, M. A. De Moya1, D. D. Yeh2  1Medical College Of Wisconsin,Surgery/ Trauma And Acute Care Surgery,Milwaukee, WI, USA 2University Of Miami,Surgery/ Trauma And Acute Care Surgery,Miami, FL, USA

Introduction:
The need for extended post-operative antibiotics (Abx) for complicated (acute gangrenous and perforated) appendicitis (CA) remains unclear. We hypothesize that giving ≤24 hours of Abx for CA is not inferior to a longer duration in preventing infectious complications after appendectomy.

Methods:
In this post-hoc analysis of the Eastern Association for the Surgery of Trauma (EAST) Appendicitis study, only patients with intra-operative diagnosis of gangrenous, perforated appendicitis  were included. ANOVA and Chi-squared tests were used to examine the length of stay (LOS), 30-day readmission rates, surgical site infection (SSI), and intra-abdominal abscess (IAA) between those patients receiving ³96 h and ≤24 h of Abx.

Results:

There were 636 patients with complicated appendicitis. Mean age was 47 (±17) years; 359(56%) were male. A total of 192 (30%) received Abx for ≤24 h and 106 (17% of overall) received no antibiotics.  Of those that received ≥96 h of post-operative Abx, the median Abx duration was 7 [5-10] days. 92 (15%) patients were lost to 30d follow up.  Twenty-four patients developed an SSI (≤24 h=6 (0.9%), ≥ 96 h=18 (2.8%), p=0.656) and 75 developed IAA (≤24 h=11 (1.7%), ≥96 h =64 (10.1%), p=<0.001) within 30d post op.  Sixty-two (9.7%) patients underwent a secondary intervention for post-operative infection.  Most SSIs 67% (16/24) and half (38/75) of IAA occurred during the index hospitalization.  Those patients who received ≤24 h of Abx had reduced LOS (≤24 h=1[1-2], ≥96 h=3[2-5], p=<0.001), lower rates of intra-abdominal abscess (≤24 h=3 (2%), ≥96 h=37 (8%), p=0.001) and secondary intervention during index hospitalization (≤24 h=2 (1%), ≥96 h=34 (8%), p<0.001), without an increase in 30-day readmission rate (≤24 h=13 (8%), ≥96 h=39 (10%), p=0.526).

Conclusion:
Giving ≤24 h of abx to complicated appendicitis was not associated with an increase in infectious complications and may lead to shorter LOS.  Fewer days of antibiotics could be considered for these patients.