HB - CIR PED - Artigos
Permanent URI for this collection
Browse
Browsing HB - CIR PED - Artigos by Title
Now showing 1 - 10 of 32
Results Per Page
Sort Options
- Collecting system percutaneous access using real-time tracking sensors: first pig model in vivo experiencePublication . Rodrigues, PL; Vilaça, JL; Oliveira, C; Cicione, A; Rassweiler, J; Fonseca, J; Rodrigues, NF; Correia-Pinto, J; Lima, EPURPOSE: Precise needle puncture of the renal collecting system is a challenging and essential step for successful percutaneous nephrolithotomy (PCNL). This works aims to evaluate the efficiency of a new real-time electromagnetic tracking (EMT) system for in vivo kidney puncture. MATERIALS AND METHODS: Six anesthetized female pigs underwent ureterorenoscopies in order to place a catheter with an EMT sensor into the desired puncture site and to ascertain the success of puncture. Subsequently, a tracked needle with a similar EMT sensor was navigated into the sensor inside the catheter. Four punctures were performed by two surgeons in each pig: one in the kidney and one in the middle ureter, on both right and left pig sides. Number of attempts and time needed to evaluate the virtual trajectory and to perform the percutaneous puncture were outcomes measurements. RESULTS: Overall 24 punctures were easily performed without any complications. Surgeons required more time to evaluate the trajectory during ureteral puncture than kidney (median 15 versus 13 seconds, range 14 to 18 and 11 to 16 seconds, respectively; p= 0.1). The median renal and ureteral puncture time were 19 and 51 seconds respectively (range 14 to 45 and 45 to 67; p=0.003). Two attempts were needed to achieve a successful ureteral puncture. The presented technique demands presence of renal stone for testing. CONCLUSIONS: The proposed EMT solution for renal collecting system puncture proved to be highly accurate, simple and quicker. This method might represent a paradigm shift in percutaneous kidney access techniques.
- Endoscopic closure of transmural bladder wall perforationsPublication . Lima, E; Rolanda, C; Osório, L; Pêgo, JM; Silva, D; Henriques-Coelho, T; Carvalho, JL; Bergström, M; Park, PO; Mosse, CA; Swain, P; Correia-Pinto, JBACKGROUND: Traditionally, intraperitoneal bladder perforations caused by trauma or iatrogenic interventions have been treated by open or laparoscopic surgery. Additionally, transvesical access to the peritoneal cavity has been reported to be feasible and useful for natural orifice translumenal endoscopic surgery (NOTES) but would be enhanced by a reliable method of closing the vesicotomy. OBJECTIVE: To assess the feasibility and safety of an endoscopic closure method for vesical perforations using a flexible, small-diameter endoscopic suturing kit in a survival porcine model. DESIGN, SETTING, AND PARTICIPANTS: This pilot study was performed at the University of Minho, Braga, Portugal, using six anesthetized female pigs. INTERVENTIONS: Closure of a full-thickness longitudinal incision in the bladder dome (up to 10 mm in four animals and up to 20 mm in two animals) with the endoscopic suturing kit using one to three absorbable stitches. MEASUREMENTS: The acute quality of sealing was immediately tested by distending the bladder with methylene-blue dye under laparoscopic control (in two animals). Without a bladder catheter, the animals were monitored daily for 2 wk, and a necropsy examination was performed to check for the signs of peritonitis, wound dehiscence, and quality of healing. RESULTS AND LIMITATIONS: Endoscopic closure of bladder perforation was carried out easily and quickly in all animals. The laparoscopic view revealed no acute leak of methylene-blue dye after distension of the bladder. After recovery from anaesthesia, the pigs began to void normally, and no adverse event occurred. Postmortem examination revealed complete healing of vesical incision with no signs of infection or adhesions in the peritoneal cavity. No limitations have yet been studied clinically. CONCLUSIONS: This study demonstrates the feasibility and the safety of endoscopic closure of vesical perforations with an endoscopic suturing kit in a survival porcine model. This study provides support for further studies using endoscopic closure of the bladder which may lead to a new era in management of bladder rupture and adoption of the transvesical port in NOTES procedures.
- Experimental foundation for natural orifice transluminal endoscopic surgery and hybrid natural orifice transluminal endoscopic surgeryPublication . Lima, E; Rolanda, C; Autorino, R; Correia-Pinto, JNatural orifice transluminal endoscopic surgery (NOTES) is one of the most exciting concepts that has emerged recently in the surgical field. All accesses to the abdominal cavity in the porcine model using natural orifices, e.g. transgastric, transvesical, transcolonic and transvaginal, have been described and explored. The experimental feasibility of all procedures by NOTES was successfully demonstrated in the porcine model using different types of natural orifices. However, few translations to the human have been made. NOTES is in a developmental stage and much work is still needed to refine techniques, verify safety and document efficacy. This paper is an update on the experimental foundation for NOTES and hybrid NOTES and examines the opportunities presented by this new surgical vision.
- Five really easy steps to build a homemade low-cost simulatorPublication . Moreira-Pinto, J; Silva, JG; Ribeiro de Castro, JL; Correia-Pinto, JAIM: The aim of this study was to evaluate how simple it is to build a homemade low-cost simulator using a simple 5-step scheme. METHODS: A scheme explaining how to build an endoscopic surgery simulator in 5 easy steps was presented to 26 surgeons. The simulator required a pair of scissors and easy-to-find materials. Its total cost was less than €35. The participants assessed the simulator using common endoscopic training toys or ex vivo tissue and completed an anonymous query comparing it with other commercial simulators that they had experienced before. RESULTS: In all, 84.6% found the simulator really easy to build. Every participant felt that he or she could do the same simulator themselves. Comparing with other commercial available box simulators, the majority of participants found the homemade simulator easier to (a) mount and dismount, (b) transport, (c) clean, and (d) use when practicing alone. CONCLUSIONS: Anyone can build its own simulator for a small amount of money.
- In vivo assessment of gastrotomy closure with over-the-scope clips in an experimental model for varicocelectomyPublication . Rolanda, C; Lima, E; Silva, D; Moreira, I; Pêgo, JM; Macedo, G; Correia-Pinto, JBACKGROUND: Gastrotomy closure remains the major limiting factor for human translation of transgastric surgery; the over-the-scope clip (OTSC) system was proposed as a possibility for this purpose. Transgastric access is good for a pelvic approach, making varicocelectomy a possible indication for natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE: To evaluate the reliability of the OTSC system in vivo after transgastric testicular vessel ligation (varicocelectomy model). DESIGN: There were 3 experimental groups (5 animals in each): groups 1 and 3, gastrotomy dilation up to 18 mm, surgery was performed with a double-channel endoscope; group 2, gastrotomy dilation up to 13 mm, surgery was performed with a single-channel endoscope. SETTING: Surgical Sciences Research Domain, Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. INTERVENTIONS: Bilateral testicular vessel ligation by transgastric access. Gastrotomy closed with the largest version of OTSC system (12 mm): a single clip in groups 1 and 2, and 2 clips in group 3. Animals were monitored for 2 weeks, killed, and submitted for necropsy. MAIN OUTCOME MEASUREMENTS: Adequacy of closure and healing after the use of the OTSC system. Statistical analysis. RESULTS: Vessel ligation was easily achieved in all groups. Although differences in the complication rate did not reach statistical significance (P = .099), there was a clear tendency for a better prognosis in groups 2 and 3 than group 1. In fact, only 2 animals from group 1 had complications related to incomplete gastrotomy closure. LIMITATIONS: Small number of animals per group; nonrandomized study. CONCLUSIONS: The OTSC system was shown to be easy and efficient for gastrotomy closure in a survival experimental model of varicocelectomy, when correctly matching the gastrotomy size with the clip size and/or number.
- Left atrial appendage ligation with single transthoracic port assistance: a study of survival assessment in a porcine modelPublication . Moreira-Pinto, J; Ferreira, A; Miranda, A; Rolanda, C; Correia-Pinto, JBACKGROUND: Left atrial appendage (LAA) exclusion is a well-known procedure for the prevention of stroke in high-risk patients with atrial fibrillation and contraindication to long-term oral anticoagulant therapy. OBJECTIVE: To evaluate a natural orifice transluminal endoscopic surgery (NOTES) approach for LAA ligation. DESIGN: In 4 acute and 6 survival pigs, we performed LAA by using a forward-viewing, single-channel gastroscope and an operative thoracoscope with a 3-mm working channel (introduced through an 8-mm single transthoracic port). SETTING: Animal laboratory. INTERVENTIONS: The gastroscope was introduced in the thoracic cavity through an esophageal submucosal tunnel. An end loop introduced through the gastroscope was used to legate the LAA. In the survival experiments, the esophageal mucosa was closed using hemoclips. MAIN OUTCOME MEASUREMENTS: The time, safety, and feasibility of the procedure were recorded. In the survival experiments, endoscopy and postmortem examination were performed on postoperative day 14. RESULTS: Creation of a submucosal tunnel and esophagotomy were safely performed in all animals without incidents. The mean time for esophagotomy was 17.0 ± 6.3 minutes. Pericardial dissection and LAA ligation were performed in all animals but 1. The mean time for LAA ligation was 34.4 ± 19.1 minutes. No adverse events occurred during the survival period. Endoscopy showed complete esophageal closure. Postmortem examination revealed pleural adhesions on the site of pericardial dissection, and the LAA was fibrotic with the endoloop in place. LIMITATIONS: Animal study. CONCLUSIONS: LAA ligation with single transthoracic trocar assistance is feasible and may be an alternative to anticoagulant therapy or to permanent intracardiac implants in patients with atrial fibrillation.
- Leukemia inhibitory factor in rat fetal lung development: expression and functional studiesPublication . Nogueira-Silva, C; Piairo, P; Carvalho-Dias, E; Peixoto, FO; Moura, RS; Correia-Pinto, JBACKGROUND: Leukemia inhibitory factor (LIF) and interleukin-6 (IL-6) are members of the family of the glycoprotein 130 (gp130)-type cytokines. These cytokines share gp130 as a common signal transducer, which explains why they show some functional redundancy. Recently, it was demonstrated that IL-6 promotes fetal lung branching. Additionally, LIF has been implicated in developmental processes of some branching organs. Thus, in this study LIF expression pattern and its effects on fetal rat lung morphogenesis were assessed. METHODOLOGY/PRINCIPAL FINDINGS: LIF and its subunit receptor LIFRα expression levels were evaluated by immunohistochemistry and western blot in fetal rat lungs of different gestational ages, ranging from 13.5 to 21.5 days post-conception. Throughout all gestational ages studied, LIF was constitutively expressed in pulmonary epithelium, whereas LIFRα was first mainly expressed in the mesenchyme, but after pseudoglandular stage it was also observed in epithelial cells. These results point to a LIF epithelium-mesenchyme cross-talk, which is known to be important for lung branching process. Regarding functional studies, fetal lung explants were cultured with increasing doses of LIF or LIF neutralizing antibodies during 4 days. MAPK, AKT, and STAT3 phosphorylation in the treated lung explants was analyzed. LIF supplementation significantly inhibited lung growth in spite of an increase in p44/42 phosphorylation. On the other hand, LIF inhibition significantly stimulated lung growth via p38 and Akt pathways. CONCLUSIONS/SIGNIFICANCE: The present study describes that LIF and its subunit receptor LIFRα are constitutively expressed during fetal lung development and that they have an inhibitory physiological role on fetal lung
- Local fetal lung renin-angiotensin system as a target to treat congenital diaphragmatic herniaPublication . Nogueira-Silva, C; Carvalho-Dias, C; Piairo, P; Nunes, S; Baptista, MJ; Moura, RS; Correia-Pinto, JAntenatal stimulation of lung growth is a reasonable approach to treat congenital diaphragmatic hernia (CDH), a disease characterized by pulmonary hypoplasia and hypertension. Several evidences from the literature demonstrated a possible involvement of renin-angiotensin system (RAS) during fetal lung development. Thus, the expression pattern of renin, angiotensin-converting enzyme, angiotensinogen, type 1 (AT₁) and type 2 (AT₂) receptors of angiotensin II (ANGII) was assessed by immunohisto-chemistry throughout gestation, whereas the function of RAS in the fetal lung was evaluated using fetal rat lung explants. These were morphometrically analyzed and intracellular pathway alterations assessed by Western blot. In nitrofen-induced CDH model, pregnant rats were treated with saline or PD-123319. In pups, lung growth, protein/DNA ratio, radial saccular count, epithelial differentiation and lung maturation, vascular morphometry, right ventricular hypertrophy and overload molecular markers, gasometry and survival time were evaluated. Results demonstrated that all RAS components were constitutively expressed in the lung during gestation and that ANGII had a stimulatory effect on lung branching, mediated by AT₁ receptor, through p44/42 and Akt phosphorylation. This stimulatory effect on lung growth was mimicked by AT₂-antagonist (PD-123319) treatment. In vivo antenatal PD-123319 treatment increased lung growth, ameliorated indirect parameters of pulmonary hypertension, improved lung function and survival time in nonventilated CDH pups, without maternal or fetal deleterious effects. Therefore, this study demonstrated a local and physiologically active RAS during lung morphogenesis. Moreover, selective inhibition of AT₂ receptor is presented as a putative antenatal therapy for CDH.
- Local Fetal Lung Renin-Angiotensin System as a Target to Treat Congenital Diaphragmatic HerniaPublication . Nogueira-Silva, C; Carvalho-Dias, E; Piairo, P; Nunes, S; Baptista, MJ; Moura, RS; Correia-Pinto, JAntenatal stimulation of lung growth is a reasonable approach to treat congenital diaphragmatic hernia (CDH), a disease characterized by pulmonary hypoplasia and hypertension. Several evidences from the literature demonstrated a possible involvement of renin-angiotensin system (RAS) during fetal lung development. Thus, the expression pattern of renin, angiotensin-converting enzyme, angiotensinogen, type 1 (AT(1)) and type 2 (AT(2)) receptors of angiotensin II (ANGII) was assessed by immunohistochemistry throughout gestation, whereas the function of RAS in the fetal lung was evaluated using fetal rat lung explants. These were morphometrically analyzed and intracellular pathway alterations assessed by Western blot. In nitrofen-induced CDH model, pregnant rats were treated with saline or PD-123319. In pups, lung growth, protein/DNA ratio, radial saccular count, epithelial differentiation and lung maturation, vascular morphometry, right ventricular hypertrophy and overload molecular markers, gasometry and survival time were evaluated. Results demonstrated that all RAS components were constitutively expressed in the lung during gestation and that ANGII had a stimulatory effect on lung branching, mediated by AT(1) receptor, through p44/42 and Akt phosphorylation. This stimulatory effect on lung growth was mimicked by AT(2)-antagonist (PD-123319) treatment. In vivo antenatal PD-123319 treatment increased lung growth, ameliorated indirect parameters of pulmonary hypertension, improved lung function and survival time in non-ventilated CDH pups, without maternal or fetal deleterious effects. Therefore, this study demonstrated a local and physiologically active RAS during lung morphogenesis. Moreover, selective inhibition of AT(2) receptor is presented as a putative antenatal therapy for CDH.
- Low-cost reusable instrumentation for laparoendoscopic single-site nephrectomy: assessment in a porcine modelPublication . Autorino, R; Kim, FJ; Rane, A; De Sio, M; Stein, RJ; Micali, S; Correia-Pinto, J; Kaouk, JH; Lima, EPURPOSE: To test different sets of prebent instruments and a new reusable access device for laparoendoscopic single-site (LESS) surgery. MATERIALS AND METHODS: Three surgeons with previous experience in LESS performed 12 nephrectomies in six pigs. In all procedures, a multichannel access device (X-CONE) and a 5-mm extra-long telescope were used. Four sets of prebent instruments with different profiles (S-portal) were tested: Standard (one straight scissors and one curved grasper), Cuschieri, Carus, and Leroy set (each of them consisting of two curved instruments with different configurations). Assessment was performed based on both objective (procedure time; time to manage the pedicle; time to free kidney) and subjective parameters (entry/exit of instruments; triangulation; dissection up/down; dissection lateral; retraction; interdependence). The subjective assessment tool used was a Likert type scale (1 = easy to 5 = prohibitive). The access device was assessed by using objective (time to complete insertion of device after skin incision) and subjective (significant air leakage, movement constraint) parameters. RESULTS: Time to insertion of the X-CONE was <1 minute in all the cases. Surgeons reported significant insufflant leakage in 58% of cases. The procedure was completed in 10/12 (83%) cases. Mean operative time was 8.3 ± 4.2 minutes, being lower for the Carus group (4.5 min) and higher for the standard group (13 min). Among the different sets, the standard one obtained the best mean scores for all subjective parameters. CONCLUSIONS: X-CONE allows easy abdominal access, and its reusable properties represent cost savings for LESS compared with disposable devices. Prebent instruments might also represent attractive low-cost tools for LESS.