Introduction Drainage of infected pleural fluid is a key component in the management of paediatric empyema. There is significant controversy regarding management policy resulting in substantial variation in treatment between tertiary centres in the UK. We have compared different primary pleural drainage strategies using a multicentre cohort design.

Methods Demographic and clinical data on cases of paediatric empyema undergoing pleural drainage were obtained from 19 centres from September 2006 until March 2011. Primary management strategy was defined as that used in the first 48 h of pleural drainage. Robust multivariate survival models were used to analyse length of stay (LOS) and incorporated a frailty term to account for institutional differences. All models were adjusted for age, sex, length of pre-hospital illness, comorbidity and intensive care admission. Fisher's exact test was used to compare readmission and pneumothorax rates.

Results Four pleural drainage strategies were recorded in 637 cases (56% male, median age 4.3 years)—Thoracocentesis without fibrinolysis (TC alone, n=35), Thoracocentesis with fibrinolysis (TC-Fib, n=286), Video assisted thoracoscopic surgery (VATS, n=18) and open Thoracotomy (Tho, n=295). Median tertiary LOS was 8 days (range 3–33) and median total hospital stay (THS) 11 days (range 5–43). Results of LOS analysis are shown in Abstract P173 table 1. In comparison to TC-Fib there were no significant differences in either LOS measure for VATS or Tho. TC alone was associated with a 44% increase in LOS at the tertiary centre and a 36% increase in THS, although the THS effect was of borderline statistical significance. There were significant differences in the rates of pneumothoraces between treatment groups (TC alone 11.4%, TC-Fib 4.2%, VATS 0% and Tho 1.69%, p=0.023) but no differences in readmission rates.

Conclusions Thoracocentesis alone is associated with substantially increased length of hospital stay and increased risk of pneumothorax. There were no significant differences in length of stay or readmission rates between drainage with fibrinolysis, VATS and thoracotomy. Both thoracotomy and VATS were associated with lower risk of pneumothorax but given the overall small number of pneumothoraces this finding should be interpreted with caution.