Oxidative and pre-inflammatory stress in wedge resection of pulmonary parenchyma using the radiofrequency ablation technique in a swine model

<p>Abstract</p> <p>Background</p> <p>Radiofrequency ablation (RFA) is a thermal energy delivery system used for coagulative cellular destruction of small tumors through percutaneous or intraoperative application of its needle electrode to the target area, and for assisting partial resection of liver and kidney. We tried to evaluate the regional oxidative and pre-inflammatory stress of RFA-assisted wedge lung resection, by measuring the MDA and tumor Necrosis Factor Alpha (TNF-α) concentration in the resected lung tissue of a swine model.</p> <p>Method</p> <p>Fourteen white male swines, divided in two groups, the RFA-group and the control group (C-group) underwent a small left thoracotomy and wedge lung resection of the lingula. The wedge resection in the RFA-group was performed using the RFA technique whereas in C-group the simple "cut and sew" method was performed. We measured the malondialdehyde (MDA) and TNF-α concentration in the resected lung tissue of both groups.</p> <p>Results</p> <p>In C-group the MDA mean deviation rate was 113 ± 42.6 whereas in RFA-group the MDA mean deviation rate was significantly higher 353 ± 184 (p = 0.006). A statistically significant increase in TNF-α levels was also observed in the RFA-group (5.25 ± 1.36) compared to C-group (mean ± SD = 8.48 ± 2.82) (p = 0.006).</p> <p>Conclusion</p> <p>Our data indicate that RFA-assisted wedge lung resection in a swine model increases regional MDA and TNF-a factors affecting by this oxidative and pre-inflammatory stress of the procedure. Although RFA-assisted liver resection can be well tolerated in humans, the possible use of this method to the lung has to be further investigated in terms of regional and systemic reactions and the feasibility of performing larger lung resections.</p

Oxidative stress in wedge resection of pylmonary parenchyma using the radiofrequency ablation technique in a swine model

INTRODUCTION: Radiofrequency ablation (RFA) is a thermal energy delivery system used for coagulative cellular destruction of small tumors through percutaneous or intraoperative application of its needle electrode to the target area, and for assisting partial resection of liver and kidney. AIM: We tried to evaluate the regional oxidative and pre-inflammatory stress of RFA-assisted wedge lung resection, by measuring the MDA and tumor Necrosis Factor Alpha (TNF-α) concentration in the resected lung tissue of a swine model. MATERIAL - METHODS: Fourteen white male swines, divided in two groups, the RFA-group and the control group (C-group) underwent a small left thoracotomy and wedge lung resection of the lingula. The wedge resection in the RFA-group was performed using the RFA technique whereas in C-group the simple “cut and sew” method was performed. We measured the malondialdehyde (MDA) and TNF-α concentration in the resected lung tissue of both groups. RESULTS: In C-group the MDA mean deviation rate was 113±42.6 whereas in RFA-group the MDA mean deviation rate was significantly higher 353±184 (p=0.006). A statistically significant increase in TNF-α levels was also observed in the RFA-group (5.25±1.36) compared to C-group (mean±SD= 8.48±2.82) (p=0.006). CONCLUSION: Our data indicate that RFA-assisted wedge lung resection in a swine model increases regional MDA and TNF-a factors affecting by this oxidative and pre-inflammatory stress of the procedure. Although RFA-assisted liver resection can be well tolerated in humans, the possible use of this method to the lung has to be further investigated in terms of regional and systemic reactions and the feasibility of performing larger lung resections.ΕΙΣΑΓΩΓΗ: Η κατάλυση με τη χρήση ραδιοσυχνοτήτων (RFA –radiofrequency ablation) είναι ένα θερμικό σύστημα παροχής ενέργειας το οποίο μετατρέπεται τοπικά σε θερμότητα και χρησιμοποιείται για τη καταστροφή μικρών όγκων με διαδερμική ή διεγχειρητική εφαρμογή του ηλεκτροδίου-βελόνα, όπως επίσης και για την τμηματική εκτομή ήπατος και νεφρών, λόγω της δημιουργίας αναίμακτου χειρουργικού πεδίου ως αποτέλεσμα της θερμικής νέκρωσης των ιστών. ΣΚΟΠΟΣ: Προσπαθήσαμε να αξιολογήσουμε την τοπική οξειδωτική και προφλεγμονώδη καταπόνηση στους ιστού του πνευμονικού παρεγχύματος χοίρων πριν και μετά μιας RFA υποβοηθούμενης σφηνοειδούς εκτομής πνεύμονα, μετρώντας τις συγκεντρώσεις της μαλονδιαλδεΰδης (MDA) και του παράγοντα νέκρωσης του όγκου (TNF-α) και συγκρίνοντάς τες με αυτές της συμβατικής μεθόδου εκτομής πνεύμονα. ΥΛΙΚΟ – ΜΕΘΟΔΟΙ: Για τη μελέτη χρησιμοπιήθηκαν δεκατέσσερεις (14) λευκοί χοίροι οι οποίοι χωρίστηκαν σε δύο ομάδες, την ομάδα της θερμοκαυτηρίασης (RFA-ομάδα) και την ομάδα ελέγχου (C-ομάδα). Όλοι οι χοίροι υποβλήθηκαν υπό γενική αναισθησία σε αριστερή πλαγία θωρακοτομή και σφηνοειδή εκτομή τμήματος της γλωσσίδας του πνεύμονα. Η σφηνοειδής εκτομή της RFA-ομάδας έγινε χρησιμοποιώντας τη μέθοδο της RFA ενώ στην ομάδα ελέγχου την απλή τεχνική εκτομής και συρραφής του πνευμονικού παρεγχύματος. Πριν και μετά από την εκτομή ελήφθησαν δείγματα ιστών και κατόπιν επεξεργασίας μετρήθηκαν οι ιστικές συγκεντρώσεις των MDA και TNF-α στον πνευμονικό ιστό των δύο ομάδων. ΑΠΟΤΕΛΕΣΜΑΤΑ: Στην ομάδα C η μέση τιμή μεταβολής των συγκεντρώσεων της MDA ήταν 113 ± 42,6 ενώ στην RFA ομάδα η μέση τιμή μεταβολής ήταν σημαντικά υψηλότερη 353 ± 184 (p = 0,006). Επίσης στατιστικά σημαντική αύξηση των συγκεντρώσεων του TNF-α παρατηρήθηκε στην RFA-ομάδα (5,25 ± 1,36) σε σύγκριση με την C-ομάδα (μέσος όρος ± SD =8,48 ± 2,82) (p = 0,006). ΣΥΜΠΕΡΑΣΜΑΤΑ: Τα ευρήματα μας έδειξαν ότι η RFA-υποβοηθούμενη σφηνοειδής εκτομή του πνεύμονα σε μοντέλο χοίρων αυξάνει τις τοπικές συγκεντρώσεις των παραγόντων MDA και TNF-α αυξάνοντας κατ’ αυτό το τρόπο τη τοπική οξειδωτική και προφλεγμονώδη καταπόνηση της μεθόδου. Παρά το γεγονός ότι η RFA υποβοηθούμενη εκτομή του ήπατος μπορεί να είναι εφαρμόσιμη χειρουργική μέθοδος στον άνθρωπο, η πιθανή εφαρμογή της για την εκτομή πνευμονικού παρεγχύματος χρήζει περαιτέρω διερεύνησης ως αναφορά τη βαρύτητα του οξειδωτικού στρες και της φλεγμονώδους αντίδρασης στη συστηματική κυκλοφορία καθώς επίσης και αποτελεσματικότητα της μεθόδου για τη διενέργεια μεγαλύτερων εκτομών στον πνεύμονα

Complete Thoracoscopic Lobectomy: A new era at the ‘‘G. Papanikolaou’’ Hospital

SUMM ARY. Twenty years after the first announcement of itsapplication, thoracoscopic lobectomy has become the gold standardfor the treatment of early stage lung cancer in many large medicalcentres in other countries. This method appears to offer fasterrecovery and a lower rate of complications than the conventionalopen technique, but many thoracic surgeons, including those in theGreek national health care system, continue to argue against theeffectiveness of the method in the management of primary lungcancer. Material and Methods Between March 2009 and October2012, 17 patients with peripheral lung tumours and unrevealingbronchoscopy underwent fully thoracoscopic lobectomy. All theoperations were performed under general anaesthesia, with one-lungventilation and without the use of a rib spreader, through the creationof 3-4 ports in the ipsilateral hemithorax. Lymph node dissectionor sampling was carried out in all patients, after completion of thelobectomy. Results Specifically 4 right upper, 1 middle, 2 lowerright, 6 left upper and 4 left lower thoracoscopic lobectomies wereperformed. The mean duration of operation was 3 hours and themean duration of hospital stay was 4 days. Conclusion Thoracoscopiclobectomy is a safe, and minimally traumatic procedure that offersfaster recovery compared with the open method. The oncologicalresults are comparable to those of the open thoracotomy technique,provided that the intraoperative principles of radical resection andlymphadenectomy are maintained. Pneumon 2013, 26(2):157-161

Transverse bronchoplasty of the membranous wall after resection of an endobronchial hamartoma

Lung hamartomas are rare benign tumors of the bronchi. Their management consists of bronchoscopic excision or removal through a thoracotomy and bronchotomy whenever there is a large tumor totally obstructing the bronchial lumen. As a lung-sparing procedure is usually the aim, various bronchoplastic techniques have been described, providing a functional lumen of the repaired bronchus. We describe a simple technique that can be safely undertaken to preserve a satisfactory diameter of the bronchus or trachea and prevent a stenosis at the site of repair

Fast, three-dimensional, MR Imaging for polymer gel dosimetric applications involving high dose and steep dose gradients

Polymer gels constitute water equivalent integrating detectors, which, combined with magnetic resonance imaging (MRI), can provide accurate three dimensional (3D) dose distributions in contemporary radiotherapy applications where the small field dimensions and steep dose gradients induce limitations to conventional dosimeters. One of the main obstacles for adapting the method for routine use in the clinical setting is the cost effectiveness of the MRI readout method. Currently, optimized Carr-Purcell-Meiboom-Gill (CPMG) multiple spin echo imaging pulse sequences are commonly used which however result in long imaging times. This work evaluates the efficiency of 3D, dual-echo, k-space segmented turbo spin echo (TSE) scanning sequences for accurate dosimetry with sub-millimetre spatial resolution in strenuous radiation therapy applications. PABIG polymer gel dosimeters were irradiated with an Ir-192 High Dose Rate brachytherapy source, the 4 mm and 8 mm collimator helmets of a gamma knife unit and a custom made x-knife collimator of 1 cm diameter. Profile and dose distribution measurements using TSE are benchmarked against corresponding findings obtained by the commonly used, but time consuming, CPMG sequence as well as treatment planning calculations, Monte Carlo (MC) simulations and film measurements. The implementation of a high Turbo factor was found to provide comparable accuracy, allowing a 64-fold MRI scan acceleration compared to conventional multi-echo sequences. The availability of TSE sequences in typical MRI installations greatly facilitates the introduction of polymer gel dosimetry in the clinical environment as a practicable tool for the determination of full 3D dose distributions in contemporary radiotherapy applications. (c) 2006 Elsevier B.V. All rights reserved