Lung resection using transumbilical incision: an animal survival study.

INTRODUCTION: Transumbilical single-port surgery is a potentially less invasive approach to many types of abdominal surgeries and offers better cosmetic outcomes than conventional 3-port laparoscopic surgery. It avoids the complication of intercostal neuralgia and may reduce the risk of pulmonary complications after video-assisted thoracic surgery. This study evaluated the feasibility of transumbilical lung wedge resection. METHODS: Lung resection was performed in 11 beagle dogs weighing 5.9 to 8.5 kg. A 3-cm umbilical incision and one diaphragmatic incision were made, and an endoscopic stapler was used. The diaphragmatic incisions were repaired under video guidance using a V-Loc knotless suturing device (Covidien, Mansfield, Massachusetts). Animals were monitored daily for signs of postoperative infection. White blood cell count, C-reactive protein level, and IL-6 level were measured in all animals. Animals were euthanized 14 days after surgery and underwent necropsy evaluation. RESULTS: Accurate lung resection was achieved in 10 of 11 animals during a median operative time of 98 minutes (range 60-165). In 1 animal, transumbilical lung resection was not possible and was converted to thoracotomy. All animals survived without major postoperative complications. At necropsy, evidence of uneventful healing of the stapled resection margin and diaphragmatic wound were found. There was no evidence of vital organ injury or intrathoracic infection. CONCLUSION: A transumbilical approach to thoracic cavity exploration and stapled lung resection is technically feasible. Primary suturing of the diaphragmatic incision is a simple and effective means of diaphragmatic wound closure. This may be an alternative to video-assisted thoracic surgery for the management of simple thoracic disease.

Hemodynamic and inflammatory responses following transumbilical and transthoracic lung wedge resection in a live canine model.

BACKGROUND: Single-port transumbilical surgery is a well-established platform for minimally invasive abdominal surgery. The aim of this study was to compare the hemodynamics and inflammatory response of a novel transumbilical technique with that of a conventional transthoracic technique in thoracic exploration and lung resection in a canine model. METHODS: Sixteen dogs were randomly assigned to undergo transumbilical thoracoscopy (n = 8) or standard thoracoscopy (n = 8). Animals in the umbilical group received lung resection via a 3-cm transumbilical incision in combination with a 2.5-cm transdiaphragmatic incision. Animals in the standard thoracoscopy group underwent lung resection via a 3-cm thoracic incision. Hemodynamic parameters (e.g., mean arterial pressure, heart rate, cardiac index, systemic vascular resistance, and global end-diastolic volume index) and inflammatory parameters (e.g., neutrophil count, neutrophil 2',7' -dichlorohydrofluorescein [DCFH] expression, monocyte count, monocyte inducible nitric oxide synthase expression, total lymphocyte count, CD4+ and CD8+ lymphocyte counts, the CD4+/CD8+ratio, plasma Creactive protein level, interleukin-6 level) were evaluated before surgery, during the operation, and on postoperative days 1, 3, 7, and 14. RESULTS: Lung resections were successfully performed in all 16 animals. There were 2 surgery-related mortality complications (1 animal in each group). In the transumbilical group, 1 death was caused by early extubation before the animal fully recovered from the anesthesia. In the thoracoscopic group, 1 death was caused by respiratory distress and the complication of sepsis at 5 days after surgery. There was no significant difference between the two techniques with regard to the hemodynamic and immunologic impact of the surgeries. CONCLUSION: This study suggests that the hemodynamic and inflammatory changes with endoscopic lung resection performed by the transumbilical approach are comparable to those after using the conventional transthoracic approach. This information is novel and relevant for surgeons interested in developing new surgical techniques in minimally invasive surgery.

Transumbilical Thoracoscopy Versus Conventional Thoracoscopy for Lung Wedge Resection: Safety and Efficacy in a Live Canine Model.

PURPOSE: Transumbilical single-port surgery has been associated with less postoperative pain and offers better cosmetic outcomes than conventional 3-port laparoscopic surgery. This study compares the safety and efficacy of transumbilical thoracoscopy and conventional thoracoscopy for lung wedge resection. METHODS: The animals (n = 16) were randomly assigned to the transumbilical thoracoscopic approach group (n = 8) or conventional thoracoscopic approach group (n = 8). Transumbilical lung resection was performed via an umbilical incision and a diaphragmatic incision. In the conventional thoracoscopic group, lung resection was completed through a thoracic incision. For both procedures, we compared the surgical outcomes, for example, operating time and operative complications; physiologic parameters, for example, respiratory rate and body temperature; inflammatory parameters, for example, white blood cell count; and pulmonary parameters, for example, arterial blood gas levels. The animals were euthanized 2 weeks after the surgery for gross and histologic evaluations. RESULTS: The lung wedge resection was successfully performed in all animals. There was no significant difference in the mean operating times or complications between the transumbilical and the conventional thoracoscopic approach groups. With regard to the physiologic impact of the surgeries, the transumbilical approach was associated with significant elevations in body temperature on postoperative day 1, when compared with the standard thoracoscopic approach. CONCLUSIONS: This study suggests that both approaches for performing lung wedge resection were comparable in efficacy and postoperative complications.

Feasibility of transumbilical surgical lung biopsy and pericardial window creation.

BACKGROUND: To date there are no practical platforms for performing natural orifice transluminal endoscopic surgery in the thoracic cavity. This study evaluates the feasibility of transumbilical thoracosopy for lung biopsy and pericardial window creation. METHODS: Eleven dogs (6 in the nonsurvival group and 5 in the survival group) were used for this study. A homemade metallic tube was advanced into the abdominal cavity via a 12-mm umbilical incision. The metallic tube was advanced into the thoracic cavity through a subxyphoid diaphragmatic incision under video guidance. Access to the thoracic cavity was achieved by a flexible bronchoscope via the metallic tube. Surgical lung biopsy and pericardial window creation were performed using an electrocautery loop and needle knife. The animals were euthanized 20 minutes after the surgery was complete (nonsurvival group) or 14 days postsurgery (survival group) for necropsy evaluation. RESULTS: Eight pericardial window creations and 21 of 22 preplanned lung biopsies were completed in a median time of 72.18 minutes (range 50-105 minutes). One dog in the nonsurvival group died after tension pneumothorax due to postprocedure massive air leaks. In the survival group, the postoperative period was uneventful in all 5 dogs. Autopsies revealed no signs of vital organ injury and complete healing of the diaphragmatic incision occurred in all animals. CONCLUSIONS: The study demonstrated that transumbilical thoracoscopic surgical lung biopsy and pericardial window creation is feasible. The safety and efficacy of the transumbilical approach need to be verified by a more detailed survival study.

Feasibility of transumbilical lung wedge resection in a canine model.

BACKGROUND: Chronic wound discomfort and intercostal neuralgia are well-known postoperative complications of video-assisted thoracoscopic surgery (VATS). To explore the possibility of a surgical platform that would cause less postoperative discomfort and avoid these complications, this study evaluated the feasibility of transumbilical lung wedge resection in a canine model. MATERIALS AND METHODS: Twelve dogs (4 in the nonsurvival group and 8 in the survival group) were used in this study. Transumbilical thoracoscopy was performed using a homemade metallic tube via umbilical and diaphragmatic incisions with the animal in a supine position. After thoracic exploration, wedge resection was performed on the lung using an endoscopic stapling device placed through the transumbilical and transdiaphragmatic incisions under direct bronchoscopic guidance. The animals were sacrificed 30 minutes after the procedure (nonsurvival group) or 14 days postsurgery (survival group) for necropsy and histological evaluations. RESULTS: Eleven preplanned lung wedge resections were completed in a median time of 101 minutes (range, 65-175 minutes) with one exception due to inadequate stapling in the early phase of the experiment. There was one death directly related to postoperative massive airleaks and sepsis in the survival group. The other 7 animals had an uneventful postoperative period. Necropsies at 2 weeks after surgery confirmed successful lung resections and revealed no evidence of vital organ injury. Two animals exhibited complete healing of the diaphragmatic incision. Liver herniation was identified in 1 of 5 animals with partial wound healing. CONCLUSIONS: This preliminary animal study demonstrates that large lung wedge resection can be performed with mechanical staplers via a single transumbilical incision. Future studies will investigate the cardiopulmonary and immunologic effects of transumbilical VATS compared with conventional VATS.

Transoral endoscopic surgery versus conventional thoracoscopic surgery for thoracic intervention: safety and efficacy in a canine survival model.

PURPOSE: Transoral endoscopic surgery has been shown to be feasible and safe in both humans and animal models. The purpose of this study was to evaluate the safety and efficacy of transoral and conventional thoracoscopy for thoracic exploration, surgical lung biopsy, and pericardial window creation. METHODS: The animals (n = 20) were randomly assigned to the transoral endoscopic approach group (n = 10) or conventional thoracoscopic approach group (n = 10). Transoral thoracoscopy was performed with a flexible bronchoscope via an incision over the vestibulum oris. In conventional thoracoscopy, access to the thoracic cavity was obtained through a thoracic incision. Surgical outcomes (body weight, operating time, operative complications, and time to resumption of normal diet), physiologic parameters (respiratory rate, body temperature), inflammatory parameters [white blood cell (WBC) counts and C-reactive protein (CRP)], and pulmonary parameters (arterial blood gases) were compared for both procedures. RESULTS: The surgical lung biopsy and pericardial window creation were successfully performed in all animals except one animal in the transoral group. There was no significant difference in operating times between the groups. The increase in WBC in the transoral thoracoscopy group was significantly smaller on postoperative day 1 than in the conventional thoracoscopy group (p = 0.0029). The transoral group had an earlier return to preoperative body temperature (p = 0.041) and respiratory rate (p = 0.045) on day 7. With respect to pulmonary parameters, there was no significant difference in blood pH, pCO2, or PaCO2 between the transoral and transthoracic groups. All animals survived without complications 14 days after surgery. CONCLUSIONS: This study demonstrated that the transoral approach was comparable to conventional thoracoscopic surgery for lung biopsy and pericardial window creation in terms of safety and efficacy.

Comparison of hemodynamic and inflammatory changes between transoral and transthoracic thoracoscopic surgery.

BACKGROUND: Natural orifice transluminal endoscopy has been developed for abdominal surgical procedures. The aim of this study was to compare the surgical outcome between a novel transoral approach and a standard transthoracic approach for the thoracic cavity in a canine model. METHODS: Twenty-eight dogs were assigned to transoral (n = 14) or standard thoracoscopy (n = 14). Each group underwent thoracic exploration, pre-determined surgical lung biopsy, and pericardial window creation. Blood draws were obtained before surgery and at postoperative days 1, 3, 7, and 14. Operative time, complications, laboratory parameters, hemodynamic parameters, and inflammatory parameters were compared between the two procedures. The animals were monitored for two weeks and necropsy were performed for surgical outcome evaluation. RESULTS: The thoracic procedures were successfully performed in all of the dogs, with the exception of one animal in the transoral group. There were no serious acute or delayed complications related to surgery. There was no difference between the two surgical groups for each of the hemodynamic parameters that were evaluated. Regarding the immunological impact of the surgeries, transoral thoracoscopy was associated with significant elevations in interleukin 6 and c-reactive protein levels on postoperative days 1 and 3, respectively, when compared with the standard thoracoscopy. All dogs recovered well, without signs of mediastinitis or thoracic infection. Necropsy revealed absence of infection, no injury to vital organs, and confirmed the success of the novel procedure. CONCLUSIONS: This study suggests that both techniques were comparable with respect to procedure success rate, hemodynamic impact, and inflammatory changes. Furthermore, there was no difference in the incidence of postoperative discomfort between groups.

Feasibility and safety of endoscopic transumbilical thoracic surgical lung biopsy: a survival study in a canine model.

BACKGROUND: Transumbilical laparoscopy allows the patient to undergo various surgical procedures associated with abdominal disease. The aim of this study was to evaluate the feasibility and safety of transumbilical thoracic exploration and surgical lung biopsy in a canine survival model. METHODS: We performed the procedure in 12 dogs weighting 7.1-9.1 kg. The thoracic cavity was accessed using a metal tube inserted via umbilical and diaphragmatic incisions. After transumbilical thoracoscopy, we resected the predetermined lung lobe with an electrocautery loop. We carried out daily clinical examinations, including determination of respiratory rate and rectal temperature. Laboratory parameters (white blood cell count) and inflammatory parameters, including serum interleukin-6 and C-reactive protein, were measured before surgery and at postoperative days 1, 3, 7, and 14. We performed necropsies 2 wk after surgery. RESULTS: We successfully performed corrected surgical lung biopsies for the predetermined lung lobe in all animals, with a median time of 43.5 min (range, 32-65 min). We observed two perioperative complications: One dog had minor postoperative air leakage and one had hemodynamic collapse because of inadequate ventilation. These animals recovered well without signs of perioperative infection. Necropsies at 2 wk after surgery showed no evidence of mediastinitis or peritonitis. CONCLUSIONS: Exposure of the thoracic cavity and surgical lung biopsy via a transumbilical incision is feasible in this canine model of survival. This procedure may have potential advantages over currently used transthoracic thoracoscopy techniques.

The lateral decubitus position improves transoral endoscopic access to the posterior aspects of the thorax.

BACKGROUND: The success of natural orifice transluminal endoscopic surgery (NOTES) depends on an adequate exploration of surgical regions. Currently, limited data are available regarding the optimal position for the NOTES approach for thoracic surgery. This study therefore aimed to evaluate the effectiveness of transoral thoracic exploration in a canine model placed in a lateral decubitus position. METHODS: A total of 14 dogs were used in this study. Transoral thoracoscopy was performed using a custom-made metal tube via an incision over the vestibular incision with the animal in a supine position. After thoracic exploration, the animal was placed in a lateral decubitus position. The thoracic intervention (surgical lung biopsy, pericardial window creation, and dorsal sympathectomy) was performed by passing a flexible bronchoscope through the lumen of a metal tube. RESULTS: The mean operative time for this procedure was 70 min (range 45-100 min). For 12 dogs, all procedures were completed without major complications. However, for one dog, the exploration of the thoracic cavity was incorrect (the right lower lobe had been misinterpreted as the left lower lobe). Another dog had minor bleeding because of an intercostal artery injury that occurred during sympathectomy. CONCLUSION: The posterior aspect of the thoracic cavity can be exposed via a transoral approach with the animal in a lateral decubitus position. This approach may be considered as an adjuvant to the supine approach, in which exploration of the posterior thoracic cavity is restricted.

Feasibility of endoscopic transoral thoracic surgical lung biopsy and pericardial window creation.

BACKGROUND: The thoracic cavity approach for natural orifice transluminal endoscopic surgery (NOTES) is technically challenging. The aim of this study was to evaluate the feasibility of a transoral endoscopic technique for a surgical lung biopsy and pericardial window creation METHODS: Under general anesthesia, a 12 mm incision was made over the vestibulum oris region. Under video guidance, a homemade metallic tube was introduced through the incision, extending along the pre-tracheal space to the substernal space with blunt dissection technique, and used as the entrance into the thoracic cavity. A surgical lung biopsy and a pericardial window creation were performed in 12 canines, using the transoral NOTES technique. RESULTS: The transoral endoscopic surgical lung biopsy and pericardial window creation were successfully completed in 11 of the 12 canines. Intraoperative bleeding and death from an injury to the pulmonary hilum developed in one animal during the electrosurgical excision of lung tissue. CONCLUSIONS: Transoral surgical lung biopsy and pericardial window creation in canine models is technically feasible and can be used as a novel experimental platform for studies of NOTES for intra-thoracic surgery.

Feasibility of endoscopic transoral surgical lung biopsy in a live canine model.

BACKGROUND: The feasibility of using a transoral approach to the thoracic cavity has not yet been measured in humans or animals. The present study aimed to evaluate the feasibility of transoral surgical lung biopsy (TOLB) in 10 canines. METHODS: Through an incision over the vestibulum oris, a homemade metal tube was introduced into the thoracic cavity under endoscopic guidance and used as a working channel of surgical lung biopsy. TOLB was performed on the predetermined lung lobe by using an electrocautery loop and endoscopic grasper. RESULTS: Successful surgical lung biopsy was achieved in 8 of 10 animals in a mean time of 132 minutes (range 130-190 minutes). There were no major intraoperative or postoperative complications, and all animals survived for 2 weeks after surgery. Autopsy showed no evidence of vital structure injury, mediastinitis, or empyema. CONCLUSIONS: TOLB was demonstrated to be safe and feasible in a canine model.

Single-dose antimicrobial prophylaxis in transoral surgical lung biopsy: a preliminary experience.

BACKGROUND: The feasibility of the transtracheal approach to the thoracic cavity has been demonstrated, but surgical lung biopsy via the tracheal approach still remains a challenge. This study aimed to evaluate the feasibility and outcome of transoral surgical lung biopsy under a single preoperative dose of parenteral antibiotics. METHODS: Transoral thoracoscopy and surgical lung biopsy were performed for 10 anesthetized dogs after a single intravenous injection of cefazoline (20 mg/kg). A 12-mm transoral incision was created on the vestibulum, and a homemade metallic tube was advanced into the thoracic cavity via the pretracheal and substernal space under endoscopic guidance. After thoracic exploration, surgical lung biopsy was performed using an electrosurgical snare with a flexible bronchoscope inserted through the metallic tube. The resection margin of the lung was secured with a homemade endoloop. The animals were killed by day 14 after the surgery for gross and histologic evaluations. RESULTS: The thoracic cavity was evaluated and lung biopsy was performed successfully (for 3 lobes in the right lung and 2 lobes in the left lung) in 9 of the 10 dogs. Neither mortality nor intraoperative complications were observed. The average time for the transoral thoracoscopy and surgical lung biopsy was 133.5 min. Postmortem examination showed complete healing, with fibrosis and moderate adhesion over the resection margin. No evidence of either mediastinitis or intrathoracic infection was observed. CONCLUSION: This study showed the feasibility of transoral thoracoscopy and surgical lung biospy in dogs. Moreover, single-dose prophylaxis with cefazoline in transoral surgical lung biopsy was found to be effective in preventing potential infection.