Platelet-Rich Plasma for Pleurodesis: An Experimental Study in Rabbits.

Background and Objectives: This study was designed to evaluate platelet-rich plasma (PRP) as a method of pleurodesis in a rabbit model. Pleurodesis with PRP was compared against the gold-standard use of talc. The secondary evaluation assessed the ideal time for achieving pleurodesis. Materials and Methods: 25 healthy New Zealand white rabbits were assigned to three groups, as follows: 12 animals in the first and second groups, as well as one animal with no intervention in the final group, which was used as a control. The talc pleurodesis group (baseline) underwent pleurodesis with sterile talc, which is the gold-standard sclerosing agent used for pleurodesis. The PRP group underwent pleurodesis using autologous PRP. The last group had one rabbit with no intervention. A total of 12 rabbits (n = 6 for the talc pleurodesis group and n = 6 for the PRP group) were sacrificed 3 days (72 h) after the intervention, and 12 rabbits (n = 6 for the talc pleurodesis group and n = 6 for the PRP group) were sacrificed 6 days (144 h) after the intervention. In both the talc and PRP group, FBC and CRP were measured before the intervention and in 3 or 6 days afterwards, respectively. The pleura and the lungs were evaluated histopathologically. Results: Macroscopically, there were no statistically significant differences between the two groups. In terms of microscopic findings, there were no statistically significant differences in inflammatory reactions provoked in the visceral and parietal pleura between the PRP and talc. In addition, with talc pleurodesis, a foreign-body reaction was observed in about 50% of the cases, which was not observed with PRP. In terms of inflammation between 3 and 6 days, there were no statistically significant differences with PRP, there was only a statistically significant difference between 3 and 6 days regarding the parietal pleura in the talc group. Conclusions: The instillation of autologous PRP in the pleural cavity shows promise in achieving pleurodesis. The efficacy of PRP as a pleurodesis agent should be examined further.

Differential Survival Characteristics of Sarcomatoid Subtype in Biphasic Pleural Mesothelioma.

BACKGROUND: Biphasic pleural mesothelioma (BPM) accounts for approximately 10% of all pleural mesothelioma. Our aim was to assess the clinical, radiologic, and pathologic factors impacting survival in BPM and to better identify patients most likely to benefit from active treatment. METHODS: A 10-year retrospective review was made of 214 biopsy-proven BPM cases with minimum 2-year follow-up. Patients with insufficient tissue for analysis were excluded (n = 96). Clinical and pathologic factors were evaluated along with radiologic assessment of pleural thickness. Survival was measured from time of diagnosis. Univariable and multivariable predictors of survival were evaluated. RESULTS: In all, 118 patients were included; 28 underwent pleurectomy/decortication, with 27 receiving additional modalities. Ninety patients underwent chemotherapy (n = 18) or radiotherapy alone (n = 9), 63 received combination therapy, and 27 received best supportive care. Median overall survival was 11.2 months (range, 0.3 to 36.2). At univariable analysis, pleurectomy/decortication (p = 0.0061), radiotherapy (p < 0.0001), and chemotherapy (p < 0.0001) were associated with superior survival when compared with best supportive care alone. Pleurectomy/decortication demonstrated 40% survival improvement compared with no surgery (p = 0.122). In a multivariable model, necrosis was negatively prognostic (hazard ratio 2.1, SE 0.76). Furthermore, increased sarcomatoid component was associated with worse survival without radiotherapy. CONCLUSIONS: BPM prognosis remains poor despite multimodality treatment. Anticancer treatment is associated with superior outcome in this nonrandomized retrospective series. Our findings suggest superior survival for patients with a lower proportion of sarcomatoid disease, with selective benefit of radiotherapy in higher proportions of sarcomatoid disease. When planning active treatment, the potential survival benefits require balancing against associated morbidity and recovery period.

In patients undergoing lung resection is it safe to administer amiodarone either as prophylaxis or treatment of atrial fibrillation?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether the administration of amiodarone is safe in patients undergoing lung resection either for prophylaxis or treatment of de novo postoperative atrial fibrillation (POAF). A total of 30 papers were identified, of which 13 represented the best evidence to answer the clinical question. The authors, journal, date, study type, country of publication, patient demographics, relevant outcomes and results were tabulated. Among the identified papers, there were 2 meta-analyses, 1 best evidence topic and 3 randomized studies, while the remainder were retrospective. When considering perioperative amiodarone for the prophylaxis of POAF, 3 randomized studies reported no significantly increased postoperative complications or amiodarone-related side effects. Mortality and length of hospital stay were similar in patients receiving amiodarone compared with either no amiodarone or other prophylactic antiarrhythmic medication. When considering amiodarone for the treatment of POAF, 1 study reported a significantly increased incidence of ARDS after anatomical lung resection (P < 0.001). Two case series reported that patients developing POAF after lung resection and managed with amiodarone also had either none or acceptable rates of side effects, with no serious respiratory complications. Two retrospective and 1 prospective observational study reported that amiodarone used either for the treatment of POAF, or for prophylaxis against it, had similar rates of postoperative respiratory complications, length of hospital stay and mortality, compared with either no treatment or treatment with other prophylactic or therapeutic agents. In accordance with the Society of Thoracic Surgeons guidelines on prophylaxis and management of POAF in general thoracic surgery, these data suggest that amiodarone is a safe agent for the management of POAF after lung resection. Careful monitoring in patients treated with amiodarone after pneumonectomy should be considered because development of acute lung toxicity can increase length of hospital stay, morbidity and mortality. Further studies may also be needed to identify the subset of pneumonectomy patients at risk of pulmonary toxicity after use of amiodarone.