Efficacy of tigecycline pleurodesis: a comparative experimental study

Observational analysis on inflammatory reaction to talc pleurodesis: Small and large animal model series review

Talc pleurodesis has been associated with pleuropulmonary damage, particularly long-term damage due to its inert nature. The present model series review aimed to assess the safety of this procedure by examining inflammatory stimulus, biocompatibility and tissue reaction following talc pleurodesis. Talc slurry was performed in rabbits: 200 mg/kg checked at postoperative day 14 (five models), 200 mg/kg checked at postoperative day 28 (five models), 40 mg/kg, checked at postoperative day 14 (five models), 40 mg/kg checked at postoperative day 28 (five models). Talc poudrage was performed in pigs: 55 mg/kg checked at postoperative day 60 (18 models). Tissue inspection and data collection followed the surgical pathology approach currently used in clinical practice. As this was an observational study, no statistical analysis was performed. Regarding the rabbit model (Oryctolagus cunicoli), the extent of adhesions ranged between 0 and 30%, and between 0 and 10% following 14 and 28 days, respectively. No intraparenchymal granuloma was observed whereas, pleural granulomas were extensively encountered following both talc dosages, with more evidence of visceral pleura granulomas following 200 mg/kg compared with 40 mg/kg. Severe florid inflammation was observed in 2/10 cases following 40 mg/kg. Parathymic, pericardium granulomas and mediastinal lymphadenopathy were evidenced at 28 days. At 60 days, from rare adhesions to extended pleurodesis were observed in the pig model (Sus Scrofa domesticus). Pleural granulomas were ubiquitous on visceral and parietal pleurae. Severe spotted inflammation among the adhesions were recorded in 15/18 pigs. Intraparenchymal granulomas were observed in 9/18 lungs. Talc produced unpredictable pleurodesis in both animal models with enduring pleural inflammation whether it was performed via slurry or poudrage. Furthermore, talc appeared to have triggered extended pleural damage, intraparenchymal nodules (porcine poudrage) and mediastinal migration (rabbit slurry).

Effectiveness and predictability of pleurodesis with the Tachosil® surgical patch compared with talc poudrage: an experimental study

OBJECTIVES

The human fibrinogen/thrombin surgical patch is proposed for videothoracoscopic pleurodesis after recurrent observation in routine clinical practice of site-specific pleuro-pulmonary adhesions.

METHODS

A total of 36 experimental videothoracoscopies were performed on 18 pigs, all of which underwent a bilateral sequential procedure. The right or left side was casually approached and two 4.8 × 4.8 cm Tachosil® patches were placed over the dorsal lung surface in the highest antigravitary position through a double-port thoracoscopy. The contralateral side was subsequently entered by a single-port thoracoscopy to perform talc poudrage in accordance with current recommendations (1 g/18 kg). Thoracoscopy and autopsy were performed after 60 days to evaluate the outcome. Pleurodesis was graded on a predefined three-tier scale (none-moderate-firm); specimens were then submitted to the pathologist. The statistical analyses performed were: frequencies distribution, variables association test and hypothesis testing using binomial distribution.

RESULTS

Pleurodesis was firm in 15/18 cases (P = 0.004), moderate in 2/18, and none in 1/18 cases with the sealant matrix. Talc pleurodesis was firm in 7/18 cases and moderate in 11/18. No surgical, medical, behavioural or growth disorders were recorded. There was complete correspondence between lung surface covered by the sealant patch and pleural adhesion topography (P < 0.001) and no other sites of adhesion were found at autopsy, whereas talc effect was commonly found to produce random pleural cavity obliteration, most frequently in declivous places, with inhomogeneous pleural adhesion for tissue density and rough/smooth outline (P < 0.001). The pathologist disclosed that talc creates a variable and unpredictable inflammatory background, sometimes severe, with the development of many granulomas. Fibrin sealant patch pleurodesis is caused by connective tissue irrespective of the pleural and pulmonary anatomy.

CONCLUSIONS

The fibrin sealant patch is effective in producing localized pleurodesis in swine. The morphology and topography of the adhesions, 2 months after the patch placement, are consistent and more predictable than after talc poudrage. The latter causes a diffuse pleurodesis which is not predictable, with a predominantly gravitational location and produces a much more serious inflammatory response.

Efficacy of nonsurgical tigecycline pleurodesis for the management of hepatic hydrothorax in patients with liver cirrhosis

Chemical pleurodesis is one of the therapeutic tools to control hepatic hydrothorax. Tetracycline and derivatives have been widely accepted as an effective and safe treatment for the purpose, but availability is the big concern. Tigecycline is an antibiotic derivative of tetracycline, which has demonstrated to be an effective pleurodesing agent in animal models. The aim of the study was to document two successful tigecycline pleurodesis in patients with decompensated liver cirrhosis, who were not candidates for liver transplantation. Both patients were undergoing palliative treatment for cirrhosis and developed massive pleural effusion on the right side. They underwent chemical pleurodesis in the first instance. Diagnostic thoracocentesis was done to rule out differentials and to confirm the clinical suspicion, following which, complete drainage of pleural fluids was achieved. Tigecycline of 3 mg/kg was instilled intrapleurally via the thoracic catheter, as per the protocol. The medical records and images were thoroughly reviewed. There was no recurrence of the effusion for at least 3 months, with no detected complications in the short- or long-term follow-up. In conclusion, pleurodesis with tigecycline seems to be effective and safe for the management of symptomatic hepatic hydrothorax and should therefore be promoted in the setting of liver cirrhosis at least for a short-term relief, especially in patients who do not meet the criteria for liver transplantation.