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Peterjohn Wormald - One of the best experts on this subject based on the ideXlab platform.
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the effect of blood pressure and cardiac output on the quality of the Surgical Field and middle cerebral artery blood flow during endoscopic sinus surgery
International Forum of Allergy & Rhinology, 2016Co-Authors: Thanh Ngoc Ha, Robert Graham Van Renen, G L Ludbrook, Peterjohn WormaldAbstract:A clear Surgical Field is critical during endoscopic sinus surgery (ESS). Hypotensive anesthesia and cardiac output (CO) may optimize the Surgical Field; however, evidence of their effect on bleeding and cerebral blood flow is conflicting. The aim of this study was to evaluate the effect of blood pressure (BP) and CO on intraoperative bleeding and middle cerebral artery blood flow velocity (Vmca ) during ESS.This was a prospective randomized controlled trial. Patients undergoing ESS for chronic rhinosinusitis at a tertiary institution in 2013 were randomized to receive BP manipulation using target-controlled noradrenaline infusion during surgery to either their left or right sinuses. The contralateral side in each patient served as control. Bleeding was scored using a 0 to 10 point bleeding assessment scale (BAS, 0-10) and Vmca was measured using transcranial Doppler ultrasonography every 10 minutes or when Surgically opportune, and time-matched with BP and CO. Data was analyzed using Bland-Altman methods.A total of 105 time points were collected across a mean arterial pressure (MAP) range of 32 to 118 mmHg. Significant correlations were demonstrated between MAP and Vmca (r = 0.7, p 50% reduction in Vmca in more than 10% of time points.Balancing Surgical visibility with organ perfusion remains a challenge. The results of this study show that moderate hypotension significantly improves the Surgical Field; however reducing BP below 60 mmHg may risk cerebral hypoperfusion.
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controlling the Surgical Field during a large endoscopic vascular injury
Laryngoscope, 2011Co-Authors: Rowan Valentine, Peterjohn WormaldAbstract:Objectives: Since the advent of endonasal skull base surgery, internal carotid artery (ICA) injury has been considered the most dramatic and challenging intraoperative complication. A large vascular injury creates an immediately challenging Surgical scenario with rapid blood loss that may result in exsanguination of the patient. Recently we have developed an animal model of the endoscopic, endonasal vascular injury. We describe important Surgical steps required in managing the Surgical Field during a catastrophic vascular event. Methods: A total of 42 endoscopic carotid artery injuries and 25 endoscopic venous injuries were performed. Throughout the injuries, the “two-surgeon” technique was used to achieve Surgical Field control. Videoendoscopy was performed throughout the implementation of these Surgical techniques. Results: Techniques found useful in controlling the Surgical Field included the two-surgeon technique, careful selection of the most appropriate nostril for endoscope positioning, large bore suction placement, suction guidance of the vascular stream through the contralateral nostril, and avoidance of suction obstruction. Only once the Surgical Field could be controlled can the injury site be addressed. Conclusions: Controlling the endoscopic endonasal Surgical Field during vascular injuries relies on the cooperation of the Surgical team and a step-based approach including careful endoscopic maneuvering within the nasal corridor, and appropriate suction selection and positioning with respect to the endoscope. Laryngoscope, 2011
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the effect of β blocker premedication on the Surgical Field during endoscopic sinus surgery
Laryngoscope, 2004Co-Authors: Salil Nair, Melanie M Collins, Patrick Hung, Guy Rees, David H Close, Peterjohn WormaldAbstract:Objectives/Hypothesis: A number of previous studies have tried to assess the effects of hypotension on the Surgical Field during endoscopic sinus surgery. These studies have been limited by inadequate sample sizes, lack of a control group, and limited data collection. The aim of the present study was to determine whether the routine use of β-blockers as a pre-medication could improve the operative Field in endoscopic sinus surgery. Study Design: A prospective, randomized, double-blinded, placebo-controlled trial. Methods: Eighty patients undergoing endoscopic sinus surgery who fit the inclusion and exclusion criteria were randomly assigned to receive either a β-blocker, Metoprolol (group 1), or a placebo tablet (group 2) 30 minutes before surgery. A standard anesthetic protocol was followed. At the commencement of surgery and at regular 15-minute intervals the Surgical Field, blood loss, heart rate, blood pressure, and isoflurane concentration were assessed. Results: There was a significant difference in overall mean heart rate between the placebo and β-blocker groups (P < .0001). In the entire group, Surgical grade correlated with heart rate (r = 0.36, P < .05) but not with mean arterial blood pressure. Mean Surgical grade was similar between the placebo and β-blocker groups, but early in the study a significantly better Surgical Field was recorded in the β-blocker group (P < .001). Surgical grade was significantly better in those with a mean heart rate of less than 60 beats per minute (P < .02). Conclusion: Although “optimum” conditions were present in the patients receiving β-blocker, the authors thought that the grading system was not discriminating enough to demonstrate a significant difference between the groups. The crucial finding in the study was the correlation between heart rate and Surgical grade in the entire group. During endoscopic sinus surgery surgery, anesthetic manipulations should be directed at maintaining a low heart rate.
Rafe M Donahue - One of the best experts on this subject based on the ideXlab platform.
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multi institutional experience using human acellular dermal matrix for ventral hernia repair in a compromised Surgical Field
Archives of Surgery, 2009Co-Authors: Jose J. Diaz, Anne M Conquest, Steven J Ferzoco, Daniel Vargo, Preston R Miller, Yichen Wu, Rafe M DonahueAbstract:Background A complex ventral hernia repair (CVHR) involves a compromised Surgical Field where gastrointestinal, biliary, and genitourinary procedures are performed. Complex ventral hernia is a significant problem in trauma, emergency, and elective general surgery in which prosthetic material is contraindicated. In this clinical scenario, primary fascia closure carries a 50% risk of developing a hernia. The other option is a planned ventral hernia with delayed repair. Hypothesis Human acellular dermal matrix is a suitable implant for CVHR in a compromised Surgical Field. Design Multi-institutional, 5-year retrospective review. Setting Four academic medical centers. Patients and Methods Each center obtained institutional review board approval. Patients included in the review had undergone CVHR with human acellular dermal matrix. Data collected included age, body mass index (calculated as weight in kilograms divided by height in meters squared), comorbidities, size of fascial defect, wound classification, hospital length of stay, length of follow-up, and mortality. Primary outcomes were Surgical site infection, fistula recurrence, and hernia recurrence. Both χ 2 and logistic regression analyses were performed. Results Two hundred forty patients met the study criteria. Their mean (SD) age was 52.2 (15.0) years, and 132 (55.0%) were men. The most common comorbidity was hypertension (115 patients [47.9%]), and the mean defect size was 201 cm 2 . The mean hospital length of stay was 17.2 days, and the mean follow-up was 317 days. The overall mortality was 2.9%. The hernia recurrence rate was 17.1% (41 patients). Repair of a fistula or stoma was associated with hernia recurrence ( P = .03) and with fistula recurrence ( P Conclusions Human acellular dermal matrix is a suitable alternative for CVHR in a compromised Surgical Field. The hernia recurrence rate with human acellular dermal matrix in a compromised Surgical Field is less than that seen with primary repair, offering additional and improved Surgical options for CVHR in this group of patients. Stoma or fistula takedown at the time of CVHR continues to be associated with significant complications.
Jose J. Diaz - One of the best experts on this subject based on the ideXlab platform.
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Human Acellular Dermal Matrix for Ventral Hernia Repair in the Compromised Surgical Field
Hernia Repair Sequelae, 2020Co-Authors: Jose J. DiazAbstract:Repair of a ventral hernia is one of the most common Surgical procedures performed in the United States. Yet ventral hernia repair in the setting of a contaminated Surgical Field presents a very difficult Surgical dilemma. Prosthetic mesh has been widely employed since the 1950s for the elective repair of ventral hernias. Beyond hernia recurrence, prosthetic mesh has known complications such as infection, contracture, and intestinal fistula formation. In the setting of a clean-contaminated and/or dirty Surgical Field, prosthetic mesh is contraindicated due to high complication rates [1, 2, 3, 4].
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multi institutional experience using human acellular dermal matrix for ventral hernia repair in a compromised Surgical Field
Archives of Surgery, 2009Co-Authors: Jose J. Diaz, Anne M Conquest, Steven J Ferzoco, Daniel Vargo, Preston R Miller, Yichen Wu, Rafe M DonahueAbstract:Background A complex ventral hernia repair (CVHR) involves a compromised Surgical Field where gastrointestinal, biliary, and genitourinary procedures are performed. Complex ventral hernia is a significant problem in trauma, emergency, and elective general surgery in which prosthetic material is contraindicated. In this clinical scenario, primary fascia closure carries a 50% risk of developing a hernia. The other option is a planned ventral hernia with delayed repair. Hypothesis Human acellular dermal matrix is a suitable implant for CVHR in a compromised Surgical Field. Design Multi-institutional, 5-year retrospective review. Setting Four academic medical centers. Patients and Methods Each center obtained institutional review board approval. Patients included in the review had undergone CVHR with human acellular dermal matrix. Data collected included age, body mass index (calculated as weight in kilograms divided by height in meters squared), comorbidities, size of fascial defect, wound classification, hospital length of stay, length of follow-up, and mortality. Primary outcomes were Surgical site infection, fistula recurrence, and hernia recurrence. Both χ 2 and logistic regression analyses were performed. Results Two hundred forty patients met the study criteria. Their mean (SD) age was 52.2 (15.0) years, and 132 (55.0%) were men. The most common comorbidity was hypertension (115 patients [47.9%]), and the mean defect size was 201 cm 2 . The mean hospital length of stay was 17.2 days, and the mean follow-up was 317 days. The overall mortality was 2.9%. The hernia recurrence rate was 17.1% (41 patients). Repair of a fistula or stoma was associated with hernia recurrence ( P = .03) and with fistula recurrence ( P Conclusions Human acellular dermal matrix is a suitable alternative for CVHR in a compromised Surgical Field. The hernia recurrence rate with human acellular dermal matrix in a compromised Surgical Field is less than that seen with primary repair, offering additional and improved Surgical options for CVHR in this group of patients. Stoma or fistula takedown at the time of CVHR continues to be associated with significant complications.
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acellular dermal allograft for ventral hernia repair in the compromised Surgical Field discussion
American Surgeon, 2006Co-Authors: Jose J. Diaz, Marshall B Berkes, Oscar D Guillamondegui, Richard S Miller, Gregory J Mancini, Yuri W Novitsky, Robert R Aderhold, Stephen W BehrmanAbstract:A ventral hernia and a contaminated Surgical Field are a difficult Surgical combination. We hypothesize that acellular human dermis (AHD) can be a suitable biological tissue alternative in the repair of a ventral hernia. The study involved a retrospective review of the use of AHD in the repair of ventral hernia from 2001-2004. Inclusion criteria included a ventral hernia repair in a clean-contaminated (CC) or contaminated-dirty (CD) Surgical Field. The primary outcome of the study was wound infection and mesh removal. Patients were stratified into CC and CD, and management of a wound infection [medically managed (MM) or Surgically managed (SM)]. Seventy-five patients met the study criteria. The most common comorbidity was hypertension (45.3%). There was one death in the study (from multiple organ dysfunction syndrome). The overall wound infection rate was 33.3 per cent: 11 MM (14.7%) and 14 SM (18.7%). The average length of stay was 16.7 days (±20.8) with a mean follow-up of 275 (±209) days. Subgroup analysis: CC (n = 64) had 9 wound infections that were MM (14.1%) and 12 wound infections that were SM (18.8%); CD (n = 11) had 2 wound infections that were MM (18.2%) and 2 wound infections that were SM (18.2%). Five of 14 SM (35.7%) wound infections required removal of the mesh. Wound infection in the contaminated Surgical Field occurred 33.3 per cent of the time. Some (18.7%) of the cases required SM management, and 35.7 per cent of these required removal of the AHD.
Ryo Mochizuki - One of the best experts on this subject based on the ideXlab platform.
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Development of an Advanced Micro-neuroSurgical Robotic System for the Deep Surgical Field
The First IEEE RAS-EMBS International Conference on Biomedical Robotics and Biomechatronics 2006. BioRob 2006., 2006Co-Authors: S. Baba, Daisuke Asai, Shinichi Warisawa, Mamoru Mitsuishi, Akio Morita, Shigeo Sora, Ryo Mochizuki, T. ShiraishiAbstract:In neurosurgery, surgeons have to perform minute and precise manipulations with poor visibility due to blood or cerebrospinal fluid. It is particularly difficult to operate in the deep Surgical Field. The authors have developed a microSurgical robotic system for the neurosurgery which overcomes these difficulties with precision of mechanical system. However, it was difficult for surgeons to operate the system skillfully without long training. Therefore, to ease the operation, the authors have developed a method to realize an intuitive motion with correspondence between the master and the slave manipulators, and also have developed a method to offer the information of spatial limits of the slave manipulator to operators. The experimental results showed the effectiveness of the developed system
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microSurgical robotic system for the deep Surgical Field development of a prototype and feasibility studies in animal and cadaveric models
Journal of Neurosurgery, 2005Co-Authors: Akio Morita, Daisuke Asai, Shinichi Warisawa, Mamoru Mitsuishi, Shigeo Sora, S. Baba, Katopo Suruman, Junpei Arata, Hidechika Takahashi, Ryo MochizukiAbstract:Object. To enhance the surgeon’s dexterity and maneuverability in the deep Surgical Field, the authors developed a master‐slave microSurgical robotic system. This concept and the results of preliminary experiments are reported in this paper. Methods. The system has a master control unit, which conveys motion commands in six degrees of freedom (X, Y, and Z directions; rotation; tip flexion; and grasping) to two arms. The slave manipulator has a hanging base with an additional six degrees of freedom; it holds a motorized operating unit with two manipulators (5 mm in diameter, 18 cm in length). The accuracy of the prototype in both shallow and deep Surgical Fields was compared with routine freehand microsurgery. Closure of a partial arteriotomy and complete end-to-end anastomosis of the carotid artery (CA) in the deep operative Field were performed in 20 Wistar rats. Three routine Surgical procedures were also performed in cadavers. The accuracy of pointing with the nondominant hand in the deep Surgical Field was significantly improved through the use of robotics. The authors successfully closed the partial arteriotomy and completely anastomosed the rat CAs in the deep Surgical Field. The time needed for stitching was significantly shortened over the course of the first 10 rat experiments. The robotic instruments also moved satisfactorily in cadavers, but the manipulators still need to be smaller to fit into the narrow intracranial space. Conclusions. Computer-controlled Surgical manipulation will be an important tool for neurosurgery, and preliminary experiments involving this robotic system demonstrate its promising maneuverability.
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micro neuroSurgical system in the deep Surgical Field
Medical Image Computing and Computer-Assisted Intervention, 2004Co-Authors: Daisuke Asai, Surman Katopo, Jumpei Arata, Shinichi Warisawa, Mamoru Mitsuishi, Akio Morita, Shigeo Sora, Takaaki Kirino, Ryo MochizukiAbstract:In neurosurgery, surgeons have to perform precise manipulations with poor visibility due to the presence of blood or cerebrospinal fluid and it is particularly difficult to operate in the deep Surgical Field. The authors have developed a microSurgical system for neurosurgery in the deep Surgical Field that addresses these difficulties. The authors succeeded in suturing the carotid artery of a rat under a glass tube 120 [mm] in depth and 50 [mm] in diameter. In this paper, the authors propose the concept of robotic-assisted micro-neurosurgery. The design and the system are presented. Furthermore, the performance of the system and in-vivo experiments on rats are also reported.
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MICCAI (2) - Micro-neuroSurgical system in the deep Surgical Field
Medical Image Computing and Computer-Assisted Intervention – MICCAI 2004, 2004Co-Authors: Daisuke Asai, Surman Katopo, Jumpei Arata, Shinichi Warisawa, Mamoru Mitsuishi, Akio Morita, Shigeo Sora, Takaaki Kirino, Ryo MochizukiAbstract:In neurosurgery, surgeons have to perform precise manipulations with poor visibility due to the presence of blood or cerebrospinal fluid and it is particularly difficult to operate in the deep Surgical Field. The authors have developed a microSurgical system for neurosurgery in the deep Surgical Field that addresses these difficulties. The authors succeeded in suturing the carotid artery of a rat under a glass tube 120 [mm] in depth and 50 [mm] in diameter. In this paper, the authors propose the concept of robotic-assisted micro-neurosurgery. The design and the system are presented. Furthermore, the performance of the system and in-vivo experiments on rats are also reported.
Thanh Ngoc Ha - One of the best experts on this subject based on the ideXlab platform.
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the effect of blood pressure and cardiac output on the quality of the Surgical Field and middle cerebral artery blood flow during endoscopic sinus surgery
International Forum of Allergy & Rhinology, 2016Co-Authors: Thanh Ngoc Ha, Robert Graham Van Renen, G L Ludbrook, Peterjohn WormaldAbstract:A clear Surgical Field is critical during endoscopic sinus surgery (ESS). Hypotensive anesthesia and cardiac output (CO) may optimize the Surgical Field; however, evidence of their effect on bleeding and cerebral blood flow is conflicting. The aim of this study was to evaluate the effect of blood pressure (BP) and CO on intraoperative bleeding and middle cerebral artery blood flow velocity (Vmca ) during ESS.This was a prospective randomized controlled trial. Patients undergoing ESS for chronic rhinosinusitis at a tertiary institution in 2013 were randomized to receive BP manipulation using target-controlled noradrenaline infusion during surgery to either their left or right sinuses. The contralateral side in each patient served as control. Bleeding was scored using a 0 to 10 point bleeding assessment scale (BAS, 0-10) and Vmca was measured using transcranial Doppler ultrasonography every 10 minutes or when Surgically opportune, and time-matched with BP and CO. Data was analyzed using Bland-Altman methods.A total of 105 time points were collected across a mean arterial pressure (MAP) range of 32 to 118 mmHg. Significant correlations were demonstrated between MAP and Vmca (r = 0.7, p 50% reduction in Vmca in more than 10% of time points.Balancing Surgical visibility with organ perfusion remains a challenge. The results of this study show that moderate hypotension significantly improves the Surgical Field; however reducing BP below 60 mmHg may risk cerebral hypoperfusion.
