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Dive into the research topics where Michael R. Marvin is active.

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Featured researches published by Michael R. Marvin.


Annals of Surgery | 2008

Experience with more than 500 minimally invasive hepatic procedures.

Joseph F. Buell; Mark T. Thomas; Steven M. Rudich; Michael R. Marvin; R Nagubandi; Kadiyala V. Ravindra; Guy N. Brock; Kelly M. McMasters

Objective:To evaluate our experience with more than 500 minimally invasive hepatic procedures. Summary Background Data:Recent data have confirmed the safety and efficacy of minimally invasive liver surgery. Despite these reports, no programmatic approach to minimally invasive liver surgery has been proposed. Methods:We retrospectively reviewed all patients who underwent a minimally invasive procedure for the management of hepatic tumors between January 2001 and April 2008. Patients were divided into 3 groups: laparoscopy with intraoperative ultrasound and biopsy only, laparoscopic radiofrequency ablation (RFA), and minimally invasive resection. To compare the various forms of surgery, we analyzed the incidence of complications, tumor recurrence, mortality, and cost. Statistical analysis was performed using χ2 analysis, Student t test, Kaplan-Meier survival analysis with the log-rank test, and multivariable Cox models. Results:A total of 590 minimally invasive hepatic procedures were performed during 489 operative interventions. The representative tumor histologies were: hepatocellular carcinoma (HCC; N = 210), colorectal carcinoma (N = 40), miscellaneous liver metastases (N = 42), biliary cancer (N = 20), and benign tumors (N = 176). Thirty-five patients underwent laparoscopic ultrasound and confirmatory biopsy alone; 201 patients underwent 240 laparoscopic RFAs, and 253 patients underwent 306 minimally invasive resections. Conversion rates to open surgery for the RFA and resection group were 2% overall. One hundred ninety-nine (40.6%) patients were cirrhotic; 31 resections were performed in cirrhotic patients. Complication and mortality rates for RFA and resection were comparable (11% vs. 16%, and 1.5% vs. 1.6%). However, complication rates (14% vs. 29%; P = 0.02) and mortality (0.3% vs. 9.7%; P = 0.006) rates were higher in the cirrhotic versus noncirrhotic resection group. Overall recurrence rates for RFA and resection groups were 24% and 23%, respectively. Local recurrence rates were higher in the RFA group (6.3% versus 1.5%; P < 0.06). Overall patient survival differed between HCC patients receiving RFA alone and those receiving RFA and OLT (P < 0.0001). Overall survival for cancer patients receiving RFA versus resection differed significantly when unadjusted for other covariates (P = 0.01), and remained marginally significant in a multivariable model (P = 0.056). Conclusions:Minimally invasive hepatic surgery has become a viable alternative to open hepatic surgery. Our present data are equivalent or superior to those encountered in any large open series. Our experience with RFA confirms a low local recurrence rate and an excellent technique for bridging patients to transplantation. Morbidity and mortality rates for minimally invasive hepatic resections in cirrhotics, is similar to other reported open resection series. This series confirmed excellent interim survival rates after laparoscopic HR and superiority over RFA in the treatment of cancer, with significantly lower local tumor recurrence rate.


Annals of Surgery | 2009

Laparoscopic major hepatectomy: an evolution in standard of care.

Ibrahim Dagher; Nicholas OʼRourke; David A. Geller; Daniel Cherqui; Giulio Belli; T. Clark Gamblin; Panagiotis Lainas; Alexis Laurent; Kevin Tri Nguyen; Michael R. Marvin; M.J. Thomas; Kadyalia Ravindra; George Fielding; Dominique Franco; Joseph F. Buell

Objective:To analyze the results of 6 international surgical centers performing laparoscopic major liver resections. Summary Background Data:The safety and feasibility of laparoscopy for minor liver resections has been previously demonstrated. Major anatomic liver resections, initially considered to be unsuitable for laparoscopy, are increasingly reported by several centers worldwide. Methods:Prospective databases of 3 European, 2 U.S., and 1 Australian centers were combined. Between 1997 and 2008, 210 major liver resections were performed: 136 right and 74 left hepatectomies. Results and differences in surgical techniques between the 6 centers are outlined. Results:Surgical duration was 250 minutes (range: 90–655 minutes). Operative blood loss was 300 mL (range: 20–2500 mL). Thirty patients (14.3%) received blood transfusion. Conversion to open surgery was required in 26 patients (12.4%). Portal triad clamping was performed in 24 patients (11.4%). Median tumor size was 5.4 cm (range: 1–25 cm) and surgical margin was 10.5 mm (range: 0–70 mm). Two patients died during the postoperative period from pulmonary embolism and urosepsis. Liver-specific and general complications occurred in 17 (8.1%) and 29 patients (13.8%), respectively. Hospital length of stay was 6 days (range: 1–34 days). A further analysis of early (n = 90) and late (n = 120) experience showed improved surgical and postoperative results in the latter group. Conclusions:This multicenter study demonstrates that laparoscopic major liver resections are feasible in selected patients and results improve with experience. However, proficiency in both open liver surgery and advanced laparoscopy is compulsory and surgeons must begin with minor laparoscopic resections.


Annals of Surgery | 2009

Minimally Invasive Liver Resection for Metastatic Colorectal Cancer: A Multi-Institutional, International Report of Safety, Feasibility, and Early Outcomes

Kevin Tri Nguyen; Alexis Laurent; Ibrahim Dagher; David A. Geller; Jennifer L. Steel; Mark T. Thomas; Michael R. Marvin; Kadiyala V. Ravindra; Alejandro Mejia; Panagiotis Lainas; Dominique Franco; Daniel Cherqui; Joseph F. Buell; T. Clark Gamblin

Objective:To evaluate a multicenter, international series on minimally invasive liver resection for colorectal carcinoma (CRC) metastasis. Summary Background Data:Multiple single series have been reported on laparoscopic liver resection for CRC metastasis. We report the first collaborative multicenter, international series to evaluate the safety, feasibility, and oncologic integrity of laparoscopic liver resection for CRC metastasis. Methods:We retrospectively reviewed all patients who underwent minimally invasive liver resection for CRC metastasis from February 2000 to September 2008 from multiple medical centers from the United States and Europe. The multicenter series of patients were accumulated into a single database. Patient demographics, preoperative, operative, and postoperative characteristics were analyzed. Actuarial overall survival was calculated with Kaplan-Meier analysis. Results:A total of 109 patients underwent minimally invasive liver resection for CRC metastasis. The median age was 63 years (range, 32–88 years) with 51% females. The most common sites of primary colon cancer were sigmoid/rectum (51%), right colon (25%), and left colon (13%). Synchronous liver lesions were present in 11% of patients. For those with metachronous lesions liver lesions, the median time interval from primary colon cancer surgery to liver metastasectomy was 12 months. Preoperative chemotherapy was administered in 68% of cases prior to liver resection. The majority of patients underwent prior abdominal operations (95%). Minimally invasive approaches included totally laparoscopic (56%) and hand-assisted laparoscopic (41%), the latter of which was employed more frequently in the US medical centers (85%) compared with European centers (13%) (P = 0.001). There were 4 conversions to open surgery (3.7%), all due to bleeding. Extents of resection include wedge/segmentectomy (34%), left lateral sectionectomy (27%), right hepatectomy (28%), left hepatectomy (9%), extended right hepatectomy (0.9%), and caudate lobectomy (0.9%). Major liver resections (≥3 segments) were performed in 45% of patients. Median OR time was 234 minutes (range, 60–555 minutes) and blood loss was 200 mL (range, 20–2500 mL) with 10% receiving a blood transfusion. There were no reported perioperative deaths and a 12% complication rate. Median length of hospital stay for the entire series was 4 days (range, 1–22 days) with a shorter stay in medical centers in the United States (3 days) versus that seen in Europe (6 days) (P = 0.001). Negative margins were achieved in 94.4% of patients. Actuarial overall survivals at 1-, 3-, and 5-year for the entire series were 88%, 69%, and 50%, respectively. Disease-free survivals at 1-, 3-, and 5-year were 65%, 43%, and 43%, respectively. Conclusions:Minimally invasive liver resection for colorectal metastasis is safe, feasible, and oncologically comparable to open liver resection for both minor and major liver resections, even with prior intra-abdominal operations, in selected patients and when performed by experienced surgeons.


Surgery | 2008

Hand transplantation in the United States: experience with 3 patients.

Kadiyala V. Ravindra; Joseph F. Buell; Christina L. Kaufman; Brenda Blair; Michael R. Marvin; R Nagubandi; Warren C. Breidenbach

BACKGROUND Composite tissue allotransplantation (CTA) is a newly emerging field of transplantation that involves the simultaneous transfer of multiple tissues with differing antigenicity. Hand transplantation, the most widely recognized form of CTA, aims to improve function and the quality of life of upper limb amputees. METHODS In 1999, an institutional review board-approved hand transplantation protocol was implemented at the Jewish Hospital, University of Louisville. Suitable patients were evaluated and underwent hand transplantation. The surgical technique was akin to that used in limb reimplantation, and the immunosuppression protocol used was similar to renal transplantation. RESULTS Between 1999 and 2006, 3 patients underwent hand transplantation at our center. Although episodes of acute rejection were seen in all patients during the early postoperative period, only 1 immunologic event occurred after the first year. Graft function improved with time period. Carroll test scores were superior to those recorded with a prosthesis at the end of 1 year. Additionally, recovery of protective sensation was seen in all 3 patients and limited discriminatory sensation in 2. Complications related to immunosuppression have included cytomegalovirus infection in 2 patients, diabetes in 1, hyperlipidemia in 2, and osteonecrosis in 1. At a follow-up of 8, 6, and 1 year(s), all the recipients are healthy and have returned to a productive life. CONCLUSIONS The long-term success reported here should encourage wider application of the CTA in general and hand transplantation in particular. Methods of minimizing long-term immunosuppression need to be pursued.


Journal of The American College of Surgeons | 2011

Laparoscopic Liver Resection: An Examination of Our First 300 Patients

Robert M. Cannon; Guy N. Brock; Michael R. Marvin; Joseph F. Buell

BACKGROUND Laparoscopic liver resection is a procedure in evolution. In the last decade it has evolved from a novel procedure to a standard part of the hepatic surgeons armamentarium. Few data exist on the development of a laparoscopic resection program. STUDY DESIGN With IRB approval, a retrospective review of 300 consecutive laparoscopic liver resections was undertaken. To determine changing results and patterns of practice, the cohort was divided into 3 consecutive groups of 100 patients. Patient demographics, indications for operation, operative factors, and in-hospital outcomes were examined. Continuous variables were analyzed with the Kruskal-Wallis test; continuous variables were compared with Fishers exact test. Univariate and multivariate analyses of major complications (≥grade 3) were performed using logistic regression. RESULTS Of the 300 patients, 173 (61.6%) were female, with a median age of 54 years. There were 133 (44.3%) major resections. The median number of segments resected increased (3 vs 2, p = 0.015), as did the percentage of repeat hepatectomies (13.0% vs 2.0%, p = 0.001). At the same time, median operative time decreased (2.25 vs 3.0 hours, p < 0.001).and estimated blood loss was similar (150 mL vs 150 mL, p = 0.635). Morbidity was similar (11% vs 14%, p = 0.300), as was mortality (1% vs 3%, p = 0.625). CONCLUSIONS Laparoscopic liver resection has evolved from a novel procedure to a vital technique in liver surgery. Our group has demonstrated the ability over time to perform more difficult resections with similar morbidity and decreased operative length.


Transplant International | 2012

A review of the United States experience with combined heart-liver transplantation

Robert M. Cannon; Michael G. Hughes; Christopher M. Jones; Mary Eng; Michael R. Marvin

Since first described by Starzl, combined heart and liver transplantation (CHLT) has been a relatively rare event, although utilization has increased in the past decade. This study was undertaken to review the United States experience with this procedure; UNOS data on CHLT was reviewed. CHLT was compared with liver transplantation alone and heart transplantation alone in terms of acute rejection within 12 months, graft survival, and patient survival. Survival was calculated according to Kaplan–Meier and Cox proportional hazards. Continuous variables were compared using Student’s t‐test and categorical variables with chi‐squared. Between 1987 and 2010, there were 97 reported cases of CHLT in the United States. Amyloidosis was the most common indication for both heart (n = 26, 26.8%) and liver (n = 27, 27.8%) transplantation in this cohort. Liver graft survival in the CHLT cohort at 1, 5, and 10 years was 83.4%, 72.8%, and 71.0%, whereas survival of the cardiac allograft was 83.5%, 73.2%, and 71.5%. This was similar to graft survival in liver alone transplantation (79.4%, 71.0%, 65.1%; P = 0.894) and heart transplantation alone (82.6%, 71.9%, 63.2%; P = 0.341). CHLT is a safe and effective procedure, with graft survival rates similar to isolated heart and isolated liver transplantation.


Journal of The American College of Surgeons | 2011

Is Laparoscopic Repeat Hepatectomy Feasible? A Tri-institutional Analysis

Zahra Shafaee; Airazat M. Kazaryan; Michael R. Marvin; Robert M. Cannon; Joseph F. Buell; Bjørn Edwin; Brice Gayet

BACKGROUND A laparoscopic approach has not been advocated for repeat hepatectomy on a large scale. This report analyzes the experience of 3 institutions pioneering laparoscopic repeat liver resection (LRLR). The aim of this study was to evaluate the feasibility, safety, oncologic integrity, and outcomes of LRLR. STUDY DESIGN All patients undergoing LRLR were identified. Since 1997, 76 LRLRs have been attempted. Operative indications were metastasis (n = 63), hepatocellular carcinoma (n = 3), and benign tumors (n = 10). All patients had 1 or more earlier liver resections (28 open, 44 laparoscopic), including 16 major resections (en bloc removal of 3 or more Couinaud segments). RESULTS Eight conversions (11%) to open resections (n = 7) or radiofrequency ablation (n = 1) were required due to technical difficulties or hemorrhage. LRLRs included 49 wedge or segmental resections and 19 major hepatectomies. Median blood loss and operative time were 300 mL and 180 minutes. Patients with previous open liver resection (group B) experienced more intraoperative blood loss and transfusion requirements than those with earlier laparoscopic resections (group A) (p = 0.02; p = 0.01, respectively). R0 resection was achieved in 58 of 64 (91%) patients with malignant tumor. The incidence of postoperative complications and duration of hospital stay were not statistically different between the 2 groups. Bile leakages developed in 5 (6.6%) patients, including 1 requiring reoperation. There was no perioperative death. Median tumor size was 25 mm (range 5 to 125 mm) and the median number of tumors was 2 (range 1 to 7). Median follow-up was 23.5 months (range 0 to 86 months). There was no port-site metastasis. The 3- and 5-year actuarial survivals for patients with colorectal metastases were 83% and 55%, respectively. CONCLUSIONS Laparoscopic repeat hepatic resections can be performed safely and with good results, particularly in patients with earlier laparoscopic resections.


Annals of Surgery | 2013

The impact of recipient obesity on outcomes after renal transplantation.

Robert M. Cannon; Christopher M. Jones; Michael G. Hughes; Mary Eng; Michael R. Marvin

Background:The benefit of renal transplantation in obese patients is controversial, with many centers setting upper limits on body mass index (BMI) in consideration for listing patients for transplant. This study was undertaken to determine the effect of recipient obesity on delayed graft function (DGF) and graft survival after renal transplantation. Methods:Retrospective review of all renal transplant recipients in the United Network for Organ Sharing database from January 1, 2004, through December 31, 2009, was performed. Primary endpoints were DGF and non–death-censored graft survival. Comparisons were made on the basis of the following weight classes: nonobese (BMI < 30), class I obese (30 ⩽ BMI < 35), class II obese (35 ⩽ BMI < 40), and class III obese (BMI ≥ 40). Results:Multivariable logistic regression indicated a significantly increased risk for DGF in obese patients. The odds ratios for DGF compared with nonobese patients were 1.34 [95% confidence interval (CI) 1.27–1.42; P < 0.001], 1.68 (95% CI 1.56–1.82; P < 0.001), and 2.68 (95% CI 2.34–3.07; P < 0.001) for the class I obese, class II obese, and class III obese groups, respectively. Class I obesity was not a significant risk for non–death-censored graft failure [hazard ratio (HR) 1.00, 95% CI 0.95–1.05; P = 0.901] compared with nonobese patients. Patients in the class II obese (HR 1.15, 95% CI 1.07–1.24; P < 0.001) and class III obese (HR 1.26, 95% CI 1.11–1.43; P < 0.001) groups were at a significantly increased risk for graft failure than their nonobese counterparts. Conclusions:Obese patients in all weight classes are at an increased risk for DGF after renal transplantation, although differences in non–death-censored graft survival are such that transplantation should not be denied on the basis of BMI criteria alone.


Journal of The American College of Surgeons | 2013

To Pump or Not to Pump: A Comparison of Machine Perfusion vs Cold Storage for Deceased Donor Kidney Transplantation

Robert M. Cannon; Guy N. Brock; R. Neal Garrison; Jason W. Smith; Michael R. Marvin; Glen A. Franklin

BACKGROUND A recent multicenter European trial has demonstrated reduced rates of delayed graft function when kidneys undergo machine perfusion before transplantation. This study was undertaken to evaluate the impact of machine perfusion on early kidney transplant function in the United States. STUDY DESIGN Retrospective review of United Network for Organ Sharing data from January 1, 2005 through March 31, 2011 was undertaken. Comparisons were made between kidneys that underwent machine perfusion (MP) vs cold storage (CS) alone in terms of delayed graft function (DGF). The analysis was performed in a cohort of MP and CS kidneys matched by propensity scoring, as well as in a cohort of paired kidneys from the same donor in which one underwent MP and the other underwent CS. Secondary end points analyzed included recipient length of stay after transplantation and graft survival. RESULTS In the overall cohort, rates of DGF were similar for MP and CS kidneys (25.7% vs 25.0%; p = 0.082), likely due to preferential use of MP in marginal kidneys. In the propensity matched cohort, MP was associated with significantly lower rates of DGF compared with CS (21.1% vs 29.1%; p < 0.001). These findings were corroborated by the paired kidney analysis, in which DGF occurred in 19.7% of the MP group compared with 27.5% of the CS group (p < 0.001). There was no difference in the hazard for graft failure between the MP and CS group in the propensity matched analysis (hazard ratio = 0.98; p = 0.622) and in the paired kidney analysis (hazard ratio = 1.02; p = 0.839). CONCLUSIONS Machine perfusion of deceased donor kidneys results in significantly decreased rates of DGF.


Transplantation Reviews | 2010

Review of the use of hepatitis B core antibody-positive kidney donors.

Rosemary Ouseph; Mary Eng; Kadiyala V. Ravindra; Guy N. Brock; Joseph F. Buell; Michael R. Marvin

This article reviews the risks of transplanting hepatitis B core antibody (anti-HBc)-positive (+) kidneys and strategies to minimize the risks to the recipient. In the United States, there is a shortage of kidneys available for transplantation. Presently, 4% of kidneys transplanted are anti-HBc (+). In published retrospective studies, the serologic conversion rate for recipients of anti-HBc (+) kidneys varied between 0% and 27%; and the development of elevated hepatic transaminases varied between 0% and 26%. Only one published article had a trend toward increased risk of graft loss. Other published studies had no significant difference in graft or patient survival. Factors that influence the risk of transmission include hepatitis B viral load, vaccination, and antiviral therapy. If the donor is anti-HBc (+) and hepatitis B DNA negative, the risk of transmission is negligible; unfortunately, this information may not be available at the time of transplant. Vaccinated recipients with a protective hepatitis B surface antibody of at least 10 mIU/mL had a 4% conversion rate compared with 10% in recipients with antibody levels not exceeding 10 mIU/mL. Both hepatitis B immunoglobulin and lamivudine have been used in recipients of anti-HBc (+) kidneys to decrease seroconversion with success. The data do support the use of anti-HBc (+) kidneys if precautions are taken. The recipients should be informed of the risk, should be vaccinated with an adequate response, and should have surveillance serologies performed.

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Mary Eng

University of Louisville

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Guy N. Brock

University of Louisville

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R Nagubandi

University of Louisville

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