Loop drainage for the emergency department treatment of abscesses: A pilot study

BACKGROUND: There is a paucity of research evaluating the effectiveness of loop drainage for treatment of skin abscesses in adult emergency department (ED) patients. OBJECTIVE: We conducted a pilot study to compare the treatment failure rates between traditional I&D with packing (I&D) vs. loop drainage (loop) in the management of skin abscess. METHODS: This was a prospective, controlled trial at an inner-city ED. We enrolled a convenience sample of consenting, adult patients with skin abscesses who were randomized to treatment with I&D or loop. Patients excluded for any of the following: severe sepsis, initial hospitalization, abscess overlying vital structures. Patients rated pain and satisfaction respectively on a 0-10 scale. Patients reexamined at 48 hours and phone interviewed 10-days post-procedure. Treatment failure defined as requiring additional intervention or hospitalization. Categorical data analyzed by chi-square; continuous data by t-tests. Alpha set at 0.05. A multivariate logistic regression was performed to evaluate association between treatment methods and failure, controlling for for potential confounding factors of gender, race, age, presence of cellulitis, cellulitis size, and co-morbid conditions. RESULTS: 37 patients enrolled; 4 lost to follow up, 40% female, 32% non-Hispanic white, mean age 42 +/-12 years. There were no significant differences for I&D vs. loop for gender, race, diabetes, chronic kidney disease, PVD, history of IVDA, obesity, concomitant cellulitis, cellulitis size, +SIRS criteria, pre-treatment narcotics, pain pre-procedure, antibiotic use, and packing duration. Treatment failure was more common in the I&D (10; 50%) vs. loop (2; 15%) group; p= 0.04). 2 patients in each group ultimately required hospitalization (p=0.68). Multivariate logistic regression revealed that treatment failure was markedly more likely in the I&D vs. loop group (OR 16.3 (95%CI 1.1-234). None of the control variables were statistically significant. Patients rated loop significantly more painful during the procedure (9.3+/-1.2 vs. 6.5+/-2.8; p=0.036). Satisfaction scores were similar between the two groups (8.8 loop vs. 9.5 I&D; p=0.48). CONCLUSION: Treatment failures were more common for I&D vs. loop drainage in patients with skin abscesses. Larger studies are warranted to confirm our findings.