PURPOSE: We investigated whether tigecycline (TG) is more effective than talc, commonly used in human clinical practice, to induce pleurodesis in rabbits.
METHODS: Saline solution (Group A, n=6, pH5.84), talc slurry (Group B, n=10, 200mg/kg, pH7.04) or parenteral TG (Group C, n=10, 25mg/kg, pH7.77; Group D, n=10, 50mg/kg, pH7.82) was randomly injected intrapleurally through a right chest tube in 36 New Zealand rabbits. Chest tube was closed for day one post-operative and removed in day four. Fluid WBC, lactate dehydrogenase and protein levels were measured daily after the injection since removing the drainage, then in day seven and before the sacrifice. All groups were equally divided in two endpoints: day 14 and day 28. At post-mortem examination, pleurodesis was graded, according to the literature, from 1 (none) to 8 (>50% symphysis), by two observers blinded to treatment groups.
RESULTS: The right pleurodesis score of Group C (6.750±0.577 at 14days, 5.400±1.817 at 28days) did not differ significantly (p=0.5987) from Group D (7.200±1.095 at 14days, 7.500±0.577 at 28days) after 14 days while it was significant after 28days (p=0.0324). Significant pleurodesis (p<0.0001) was discovered between the study Groups (C and D), and the control Group A (1.333±0.577 at 14days, 1.000 at 28days). Group B (4.000±0.577 at 14days, 4.200±1.643 at 28days) was significantly inferior to Group C in 14days sub-groups (p=0.0031) and to Group D (p<0.0009). Complications occurred only in Group D (n=3 right hemothorax+ascites and n=2 hemothorax at day 14; n=1 massive ascites at day 28). Only one rabbit of Group C (respiratory distress in XI post-op) and one of Group D (massive right hemothorax and ascites in XIV post-op) died. The left pleurodesis scores were 1.00 in all 36 rabbits.
CONCLUSION: Intrapleural TG is more effective than talc to induce pleurodesis in rabbits. TG 25mg/kg provokes similar intense pleural inflammatory response compared to TG 50 mg/kg and a less evident systemic response.
CLINICAL IMPLICATIONS: TG 25mg/kg might be used in humans for pleurodesis.
DISCLOSURE: Niccolo Daddi, No Financial Disclosure Information; No Product/Research Disclosure Information