John Schomburg

Robot-assisted laparoscopic ureteral reimplantation: A single surgeon comparison to open surgery

OBJECTIVE The aim was to report a single surgeons experience comparing open and robot-assisted laparoscopic extravesical ureteral reimplantation (RALUR) to treat vesicoureteral reflux (VUR). SUBJECTS AND METHODS We retrospectively reviewed the outcomes of RALUR and open extravesical ureteral reimplantations consecutively performed by a single surgeon between January 2008 and December 2010 using the da Vinci(®) Surgical System. Both groups of patients were subjected to identical pre- and postoperative care protocols. RESULTS During the defined study interval, 20 open and 20 RALUR procedures were completed by a single surgeon at our institution. Gender and VUR grade were similar in both cohorts. Operative times were longer in the RALUR group, but postoperative opioid use (morphine equivalents) was significantly lower in the RALUR group (RALUR: 0.14 mg/kg, open: 0.25 mg/kg, p = 0.021). There was no significant difference in estimated blood loss (EBL) or length of hospitalization (LOH). The overall rate of surgical complications was similar; however, the complications in the open group tended to be less severe than those occurring in the RALUR group. On follow-up, after a median of 52 months for open surgery and 39 months for RALUR, two children had developed a febrile urinary tract infection in both groups, of which one in the open group had persistent VUR. CONCLUSION This single-surgeon experience of open and initial experience with RALUR performed with the same surgical technique on consecutive cohorts with identical post-surgical care protocol allows a comparative analysis of outcomes for a surgeon transitioning to RALUR. The RALUR reduces postoperative analgesic requirements while yielding similar clinical outcomes as the open technique.

Dabigatran versus Warfarin after Mechanical Mitral Valve Replacement in the Swine Model

ABSTRACT Background: Mechanical heart valve replacement is an absolute indication for anticoagulation. We report our experience comparing dabigatran to warfarin as thromboembolic prophylaxis after mechanical mitral valve replacement in the swine model. Methods: Nineteen swine underwent mitral valve replacement with a regulatory approved, 27 mm mechanical valve. Two control groups consisted of three animals receiving no anticoagulation and five animals receiving warfarin (5 mg once a day [QD], adjusted to maintain international normalized ratio [INR] from 2.0 to 2.5). The experimental group consisted of 11 animals receiving dabigatran (20 mg/kg twice a day [BID]). The study period was 90 days. The primary outcome was animal mortality; secondary outcomes included presence of thrombus and bleeding complications. Results: The experimental group had four full-term survivors (40.0%); there were no full-term survivors in either control group. The average length of survival was 50.3 days in the experimental group compared with 18.7 and 15.6 days for the no anticoagulation and warfarin groups, respectively (p = .017). Valve thrombus was observed in all study groups. Hemorrhagic complications were present in 40% of the warfarin group and 27% of the dabigatran group. Conclusions: There was a significant mortality benefit to the use of dabigatran as thromboembolic prophylaxis when compared with warfarin in the setting of mechanical heart valve replacement in the swine model. There was also a decreased incidence of bleeding complications in the dabigatran group compared with the warfarin group. Valve thrombus was observed in all study groups. Any conclusions regarding the rate of thrombus formation are outside the scope of this study and merit further investigation.

Internal aortic annuloplasty: a novel technique.

ABSTRACT Background: The purpose of this study was to define an experimental model and a reproducible surgical technique for the preclinical assessment of safety and biocompatibility of a novel intra-annular internal aortic annulus repair device. Methods: Adult sheep were implanted with HAART Incs 19 mm aortic annulus repair device via a transverse aortotomy using standard anesthetic, surgical, and cardiopulmonary bypass techniques. Animals were closely monitored throughout the study period until the time of elective sacrifice at 30 or 60 days. Results: Six adult sheep, mean age 63.2 weeks, mean weight 68.8 kg, underwent aortic annuloplasty with a 19 mm annuloplasty frame. Five of the sheep remained stable until scheduled sacrifice. The primary outcome of this study was animal mortality. Early mortality was seen in only one animal (16.7%), due to a surgical complication. Mild-to-moderate aortic insufficiency was observed in all animals upon echocardiographic examination at the time of elective sacrifice. Conclusions: Of the six animals that underwent aortic annuloplasty, there was one early death due to surgical complication. The remaining five subjects were clinically stable at the time of elective sacrifice. Any conclusions regarding the cause of the observed aortic insufficiency are beyond the scope of this feasibility study but would need to be fully evaluated in the preclinical assessment of any internal aortic annuloplasty device. We have shown that we have developed a reproducible surgical technique in a physiologically appropriate model for the preclinical assessment of internal aortic annulus repair devices.

Development of a Classification Scheme for Examining Adverse Events Associated with Medical Devices, Specifically the DaVinci Surgical System as Reported in the FDA MAUDE Database

OBJECTIVE To examine the Manufacturer and User Facility Device Experience Database (MAUDE) database to capture adverse events experienced with the Da Vinci Surgical System. In addition, to design a standardized classification system to categorize the complications and machine failures associated with the device. SUMMARY BACKGROUND DATA Overall, 1,057,000 DaVinci procedures were performed in the United States between 2009 and 2012. Currently, no system exists for classifying and comparing device-related errors and complications with which to evaluate adverse events associated with the Da Vinci Surgical System. METHODS The MAUDE database was queried for events reports related to the DaVinci Surgical System between the years 2009 and 2012. A classification system was developed and tested among 14 robotic surgeons to associate a level of severity with each event and its relationship to the DaVinci Surgical System. Events were then classified according to this system and examined by using Chi-square analysis. RESULTS Two thousand eight hundred thirty-seven events were identified, of which 34% were obstetrics and gynecology (Ob/Gyn); 19%, urology; 11%, other; and 36%, not specified. Our classification system had moderate agreement with a Kappa score of 0.52. Using our classification system, we identified 75% of the events as mild, 18% as moderate, 4% as severe, and 3% as life threatening or resulting in death. Seventy-seven percent were classified as definitely related to the device, 15% as possibly related, and 8% as not related. Urology procedures compared with Ob/Gyn were associated with more severe events (38% vs 26%, p < 0.0001). Energy instruments were associated with less severe events compared with the surgical system (8% vs 87%, p < 0.0001). Events that were definitely associated with the device tended to be less severe (81% vs 19%, p < 0.0001). CONCLUSIONS Our classification system is a valid tool with moderate inter-rater agreement that can be used to better understand device-related adverse events. The majority of robotic related events were mild but associated with the device.

Extended outpatient chemoprophylaxis reduces venous thromboembolism after radical cystectomy

PURPOSE Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism, is a common cause of morbidity and mortality after radical cystectomy. The purpose of our study was to evaluate the utility of extended outpatient chemoprophylaxis against VTE after radical cystectomy-with a focus on any reduction in the incidence of VTE, including DVT and pulmonary embolism. MATERIALS AND METHODS Beginning in April 2013, we prospectively instituted a policy of extending inpatient VTE prophylaxis with subcutaneous heparin/enoxaparin for 30 days postoperatively. For this study, we reviewed the electronic medical records of all patients who underwent radical cystectomy at our institution from January 2012 through December 2015. The experimental group (n = 79) received extended outpatient chemoprophylaxis against VTE; the control group (n = 51) received no chemoprophylaxis after discharge. The primary outcome was the 90-day incidence of VTE. The secondary outcomes included the overall complication rate, the hemorrhagic complication rate, as well as the rate of readmission within 30 days of hospital discharge. RESULTS The experimental group experienced a significantly lower rate of DVT (5.06%), assessed as of 90 days postoperatively, than the control group (17.6%): a relative risk reduction of 71.3% (P = 0.021). We found no significant differences in secondary outcomes between the 2 groups, including the overall complication rate (54.4% vs. 68.6%), the hemorrhagic complication rate (3.7% vs. 2.0%), and the readmission rate (21.5% vs. 29.4%). CONCLUSION Extended outpatient chemoprophylaxis significantly reduced the incidence of VTE.

Preoperative Incidence of Deep Venous Thrombosis in Patients With Bladder Cancer Undergoing Radical Cystectomy

OBJECTIVE To determine the preoperative incidence of subclinical lower-extremity deep vein thrombosis (DVT), as well as to evaluate the utility of preoperative DVT screening in patients with bladder cancer before undergoing radical cystectomy. MATERIALS AND METHODS Beginning in 2014, we prospectively instituted a policy of obtaining a screening lower-extremity duplex ultrasound on all patients within 7 days before undergoing radical cystectomy. We reviewed the electronic medical records of all patients at our institution who underwent radical cystectomy for bladder cancer from January 2012 through December 2015. The screened group (n = 65) underwent preoperative screening; the historical control group (n = 78) did not. Primary outcome was a lower-extremity duplex ultrasound positive screening. Secondary outcome measures included the development of symptomatic venous thromboembolism (VTE) postoperatively, and the rate and severity of complications. RESULTS DVT was identified in 13.9% of patients before undergoing cystectomy. Univariate analysis demonstrated an increased risk of subclinical DVT in patients who were exposed to neoadjuvant chemotherapy (35.3% vs 5.1%, P = .008). Postoperatively, there was a nonsignificant trend of lower DVT rate in the screened group compared to historical control. Overall complication rate and severity were similar between the groups. CONCLUSION Subclinical DVT is present in a significant number of pre-cystectomy patients, especially those exposed to neoadjuvant chemotherapy. Ultrasound screening in patients before undergoing radical cystectomy may identify opportunities for early intervention to reduce morbidity and mortality associated with perioperative DVT or venous thromboembolism in the cystectomy population.

V1-02 ROBOT ASSISTED LAPAROSCOPIC PLACEMENT OF BLADDER NECK ARTIFICIAL URINARY SPHINCTER.

INTRODUCTION AND OBJECTIVES: We describe the surgical steps for performing a radial forearm free flap (RFFF) substitution urethroplasty in a patient with an obliterated urethral defect after failing an excision and primary anastomotic (EPA) urethroplasty for a pelvic fracture urethral injury (PFUI). METHODS: A 9-year old male involved in an all-terrain vehicle accident was initially treated at an outside hospital for non-operative pelvic fractures and a urethral disruption. He was managed with a suprapubic catheter. The patient was referred 5 months after the injury with a 3 cm obliterated bulbar urethral defect. We performed a posterior EPA urethroplasty with corporal splitting and partial inferior pubectomy.Onemonth after surgery, an anastomotic leak was identified on retrograde urethrogram (RUG) imaging. The urethral catheter was removed and the patient was managed with a SPT. Two months after surgery, repeat imaging was performedandanobliteratedurethraldefectwas identified.Due to theearly failure of the repair, suggesting vascular compromise and/or technical failure, we proceeded with RFFF substitution urethroplasty. RESULTS: The patient underwent RFFF urethroplasty under the coordinated care of the urology and microvascular plastic surgery team. Major steps included the following: 1) dissecting theurethraandmeasuring the lengthof theurethral defect, 2) harvesting the radial forearm freeflap, 3) tubularizing the flap over a catheter, 4) preparing the recipient femoral vessels in the inguinal region, 5) performing theurethral-flapanastomoses, and 6) performing the microvascular anastomoses. Following excision of scar, the urethral defectmeasured 10 cm. The flapwas harvested from the left forearmwhichwasclosedprimarily. Theoperationwas8:45with180cc of blood loss. During the microvascular anastomoses, an acoustic microvascular coupler was placed to audiblymonitor the vascular flowof the flap during the post-operative period. The patient was kept on bed rest for 48 hours, and the patientwas dischargedhomeonpost-operative day 4.After 3 weeks, the urethral catheter was removed and the SPT was kept to drainage since a small leakwas visualized at the proximal anastomosis on RUG imaging. The SPT was removed 3 weeks later following no visual evidence of leak on imaging. The patient continues to void without obstructive symptoms 3 months after surgery. CONCLUSIONS: Radial forearm free flap urethroplasty is a treatment option for long, obliterated urethral defects and should be performed in a multidisciplinary manner with the assistance of a microvascular plastic surgeon.

MP64-14 OUTPATIENT CHEMOPROPHYLAXIS AND RATE OF DEEP VENOUS THROMBOSIS FOLLOWING RADICAL CYSTECTOMY

INTRODUCTION AND OBJECTIVES: Radical cystectomy is associated with significant morbidity (20-60%) and mortality (1-6%). Despite ubiquitous postoperative prophylaxis in the inpatient setting, deep venous thrombosis (DVT) and venous thromboembolism (VTE) are common following cystectomy (2-9%) and contribute significantly to morbidity and mortality (6.8%). The mean time to DVT and VTE is postoperative day 15.2, suggesting that the risk of DVT and VTE persists following discharge. We sought to evaluate the benefit of extended chemoprophylaxis after hospital discharge following cystectomy in reducing incidence of deep venous thrombosis and venous thromboembolism. METHODS: Beginning in 2012, we prospectively instituted a policy of immediate pre-procedure prophylaxis with a single dose of subcutaneous heparin and continued prophylaxis with subcutaneous heparin/enoxaparin for 30 days post-operatively. We reviewed the charts of all patients who underwent radical cystectomy at our institution from January 2012-December 2013. After excluding patients who were on chronic anticoagulation for other indications as well as those who developed DVT prior to discharge, 58 patients were analyzed. The experimental group (n1⁄417) consisted of patients who received extended chemoprophylaxis while the control group (n1⁄4 41) received no chemical prophylaxis on discharge. The decision to discharge with or without prophylaxis was up to surgeon discretion at the time of discharge. The primary outcome was incidence of DVT or VTE. Secondary outcomes included overall complication rate, hemorrhagic complication rate and readmission rate. RESULTS: The cohort contained 45 men and 13 women. 44 patients underwent ileal conduit and 14 underwent continent diversion. Median age was 64.5 (range 52 to 87). The experimental group experienced a trend towards a lower rate of post-discharge DVT assessed as of 90 days postoperatively when compared to the control rate (5.8% vs. 9.8%), a 40% relative risk reduction (p1⁄40.63). There were no significant differences in secondary outcomes including rate of readmission (41% vs 42%), hemorrhagic complications (2.5% vs 5.8%) or overall complication rate (52% vs 66%). There were no significant demographic differences between control and experimental groups. CONCLUSIONS: Immediate preoperative followed by extended outpatient chemoprophylaxis following radical cystectomy is well tolerated and is associated with a trend towards lower rate of deep venous thrombosis.