- Email: [email protected]
Using Heat, Exercise, and Constrictive Pressure to Increase Vein Diameter and Arterial Flow in the Forearm
822 Abstracts
gradients and resistance, while stenosis above 80% made significant contributions to these measurements. Unfortunately, stenoses above 80% also affected the renal resistance index, making it an unreliable index to confirm intrinsic renal artery disease. Conclusions: The intrinsic microvascular resistance of the kidney has a much greater effect on renal pressure gradients and resistances until renal stenosis is at least 80% for smooth plaque. Renal artery stenting of stenoses less than 80% may not significantly benefit most patients. With renal artery stenoses greater than 80%, the stenosis has a significant effect on renal pressures and resistances, but the renal resistance index is unreliable. Patients may benefit from renal artery stenting of lesions with more than 80% stenosis, but a better means of evaluating the functional reserve of the distal vasculature is needed than the current renal resistive index.
Fig. Renal pressures, flows, and resistances.
Author Disclosures: A. P. Sawchuk: None; W. Yu: None; A. Mumbaraddi: None; M. C. Dalsing: None. Novel Open Vascular Surgery Skills Training Model Accurately Differentiates Level of Vascular Surgical Skills (Forceps Handling, Needle Driving, and Knot Tying) in General Surgery Residents, Vascular Surgery Residents, Fellows, and Faculty Farah Mohammad, MD1, Loay Kabbani, MD2, Andrew Taylor2, Robert Cuff, MD3, John Rectenwald, MD3, Otto Brown, MD3, Carlo Dall’ Olmo, MD4, Mark Mattos, MD3. 1Department of General Surgery/ Vascular Surgery, Henry Ford Hospital, Detroit, Mich; 2Henry Ford Hospital, Detroit, Mich; 3Wayne State University Program, Detroit, Mich; 4Genesys Regional Medical Center, Flint, Mich Objectives: The aim of this study was to determine if the use of a novel low-fidelity simulated vascular skills training model could differentiate levels of vascular surgical skills in general and vascular surgery residents, vascular surgery fellows, and vascular surgery faculty. Methods: Fifty-four participants from eight different surgical training programs with varying levels of experience were recruited to perform primary closure of a 5-cm longitudinal arteriotomy using a novel simulated training model. Each participant performed three primary closures. Participants were ranked into one of eight levels of experience defined by their training levels: 1 ¼ program year (PGY)-1 (n ¼ 12); 2 ¼ PGY-2 (n ¼ 6); 3 ¼ PGY-3 (n ¼ 10); 4 ¼ PGY-4 (n ¼ 4); 5 ¼ PGY-5 (n ¼ 5); 6 ¼ PGY-6 (n ¼ 4); 7 ¼ PGY-7 (n ¼ 9); and 8 ¼ Faculty (n ¼ 4). Performance was assessed by task completion times, total global rating scale, suture placement accuracy, and number of needle drops and reloads. For each primary closure performance, a global rating summary score was assigned. All data was reported and evaluated based on the mean results of the three performance trials. Results: Mean task completion times decreased and total global rating scale and global rating summary scores increased in a linear fashion according to training level (P < .001). Linear regression analysis revealed that both task completion time and total global rating score could significantly predict level of training (P < .001). Suture placement accuracy, number of needle drops, and number of needle reloads were not predictive (P > .218). Conclusions: The results indicate that the training model and assessment metrics display construct validity over progressive years of surgical training at multiple training sites. Furthermore, the results support their
JOURNAL OF VASCULAR SURGERY September 2015
use as a helpful assessment tool for the evaluation of basic vascular surgery skills. Its value as a cost- and time-effective training model for the improvement of vascular surgery skills remains to be proven. Author Disclosures: F. Mohammad: None; L. Kabbani: None; A. Taylor: None; R. Cuff: None; J. Rectenwald: None; O. Brown: None; C. Dall’ Olmo: None; M. Mattos: None. Using Heat, Exercise, and Constrictive Pressure to Increase Vein Diameter and Arterial Flow in the Forearm Neelima Katragunta, Bradley Dixon, MD. Department of Vascular Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa Objectives: The major problem limiting use of arteriovenous fistulae (AVF) for dialysis is impaired fistula maturation. We seek to find out if perioperative vascular conditioning will improve AVF maturation. During the first phase of this study, we seek to determine the effects of heat, constrictive pressure, and hand exercises on cephalic vein diameter (CVD) and brachial artery blood flow (BAF) Methods: The patients underwent a baseline measurement of CVD and BAF in both arms at the on-site vascular laboratory at room temperature (23 C) with and without 30-mm Hg upper arm pressure cuff. They then underwent a 30-minute treatment of the left arm with a heating pad and constrictive upper arm pressure of 30 mm Hg along with intermittent hand exercise to determine the maximal attained brachial artery blood flow, cephalic vein diameter, and maximum tolerated skin temperature. The patients were brought in for a second visit where baseline BAF and CVD of left forearm were obtained. Measurements were repeated with 30-mm Hg constrictive pressure and heat and intermittent hand exercises. Measurements were obtained every 3 minutes for a total of 30 minutes. Results: The study group consisted of seven older patients with chronic kidney disease, 75% of who have vascular disease and a prior history of smoking, and half have diabetes. The results demonstrate that subjects tolerate a mean skin temperature of 101.6 F for 30 minutes. Heat alone caused an increase in BAF and CVD, but the greatest increase was when we combined heat, intermittent arm exercise, and upper arm pressure. We found that 30-mm Hg upper arm pressure reduced arm blood flow and increased CVD. If we added heat and intermittent hand exercise for 30 minutes, we could increase arm blood flow by more than three-fold over baseline and vein diameter by 19% (Figs 1 and 2). During the second visit, a two-fold increase of BAF and a13% increase in CVD over the baseline was demonstrated. Conclusions: Application of heat to the forearm and constrictive pressure to the upper arm in combination with intermittent hand exercises increases the CVD and the BAF. Whether 6 weeks of such preoperative
Fig 1. Variation in brachial artery (BA) flow.
Fig 2. Variation in cephalic vein (CV) diameter.
JOURNAL OF VASCULAR SURGERY Volume 62, Number 3
treatment will improve vein size and compliance, and whether this will translate into improvement in AVF maturation is to be determined by the next two phases of the study. Author Disclosures: N. Katragunta: None; B. Dixon: None.
Bacteriology and Treatment of Aortic Graft Infection: A Modern Perspective Loren L. Masterson, MD, Elizabeth Kudlaty, Lavina Malhotra, MD, Patricia Salvador, MD, Michael Go, MD. Department of Vascular Diseases and Surgery, The Ohio State University, Columbus, Ohio Objectives: Aortic graft infection after open repair is infrequent but morbid. In the endovascular era, prevalence of infected aortic grafts may be lower but outcomes no less severe. We reviewed recent infected aortic grafts at our institution to understand contemporary bacteriology and outcomes. Methods: All infected aortic grafts from 1996 through 2014 were reviewed. Surgeries, treatments, microbiology, and outcomes were collected. Results: A total of 34 cases were identified. Average age was 64 years, and 53% were men. Twenty-three (64%) had aortobifemoral bypass, seven (22%) had aortic tube graft, three (8%) had aortoiliac bypass, and one had aortopopliteal bypass. Indication for surgery was occlusive disease in 62% and aneurysm in 38%. Sixty-seven percent of patients had total graft removal, while 33% had partial removal. Fifteen patients had excision without reconstruction, 11 had simultaneous extraanatomic bypass, and eight had staged extra-anatomic bypass. Five patients with reconstruction developed infection of the new graft requiring removal. Three of these patients had their reconstruction done simultaneously with aortic graft removal, while two had their reconstruction staged after aortic graft removal. Thirty-one patients had culture results available: 11 had no growth, three grew candida, four grew staphylococcus, three grew streptococcus, five grew enterococcus, and eight grew multiple organisms. Thirtyday mortality after graft removal was 26%. Eight patients eventually came to amputation; three of these patients had a failed extra-anatomic bypass. Conclusions: Explantation and extra-anatomic bypass may still be considered standard treatment for aortic graft infection, but mortality and limb loss remain high. Bacterial species are heterogeneous and many infections are polymicrobial. Tailoring contemporary available treatments including medical management, excision without reconstruction, partial excision, and deep-vein or antibiotic-soaked graft inline reconstruction as cases permit are all reasonable given the morbidity of standard treatment.
Abstracts 823
Analysis of BP did not yield a significant difference between preoperative, 30-day, and 12-month follow-up measurements (P ¼ .893; systolic BP). There was no significant change to number and type of BP medications preoperatively, at 30 days, or at 12 months (P ¼ .145). Conclusions: eCEA has no significant short- or long-term effects on BP or number of BP medications compared with cCEA. Author Disclosures: B. C. Adams: None; M. R. Pedersen: None; M. S. Hosn: None; T. F. Kresowik: None; L. Pascarella: None. Long-Term Health Care Utilization Analysis of Open and Endovascular Abdominal Aortic Aneurysm Repair Emily A. Wood, MD, Manju Kalra, MD, Peter Gloviczki, MD, Audra A. Duncan, MD, Gustavo S. Oderich, MD, Mark D. Fleming, MD, Randall R. De Martino, MD, William S. Harmsen, Thomas C. Bower, MD. Mayo Clinic, Rochester, Minn Objectives: The Open versus Endovascular Repair Veterans Affairs Cooperative Study (OVER) demonstrated that total health care costs are not significantly different between the open (OR) and endovascular (EVAR) abdominal aortic aneurysm (AAA) repair out to 2 years. The aim of this study was to evaluate initial and long-term health care resource utilization of OR and EVAR in a non-Veterans Affairs, non-trial study population. Methods: Data from patients undergoing AAA repair between January 1, 2007 and December 31, 2009 at a single institution were obtained from a prospectively maintained database and retrospectively analyzed. Follow-up information was collected through January 15, 2015. Results: There were 475 patients (293 EVAR, 182 OR); OR patients were significantly younger (71 vs 77 years; P < .0001) and more often female (20% vs 10%; P ¼ .014). Median length of stay was significantly lower following EVAR: 2 days (range, 1-34 days) vs 7 days (range, 3-89 days) for OR (P < .00001). Mortality at 30 days for EVAR/OR was 0.7/0.5; median follow-up was 5.1/5.5 years. Eighty percent of EVAR and 75% of OR patients had a least one follow-up surveillance visit; 78% and 64% at least
Author Disclosures: L. L. Masterson: None; E. Kudlaty: None; L. Malhotra: None; P. Salvador: None; M. Go: None. The Long-Term Effects of the Type of Carotid Endarterectomy on Blood Pressure Brian C. Adams, MD, Mark R. Pedersen, MD, Maen S. Hosn, MD, Timothy F. Kresowik, MD, Luigi Pascarella, MD. University of Iowa Hospitals and Clinics, Iowa City, Iowa Objectives: Carotid endarterectomy (CEA) has been one of the most studied and scrutinized operative procedures in vascular surgery. Retrospective series and randomized trials have shown no difference in perioperative stroke and long-term restenosis between conventional patch angioplasty (cCEA) and eversion (eCEA). A number of authors have shown acute hemodynamic disturbances in the immediate postoperative period leading to a temporary hypertensive state. eCEA may increase the risk of postoperative hypertension due to the more extensive dissection of the carotid bulb. Studies have documented this hypertensive phenomenon in the immediate postoperative period; however, there is little data found evaluating the longterm effects. The objective of this study is to evaluate the hemodynamic disturbances following eCEA vs cCEA at short- and long-term follow-up. Methods: A retrospective review of patients who underwent CEA between July 1, 2009 and June 30, 2014 was conducted at our institution. Demographics, comorbidities, blood pressure (BP), and number and type of antihypertensive medications were collected preoperatively, at 30 days, and at 12 months. The differences in BP and medications between cCEA and eCEA patients were compared. Demographic data and comorbidities were compared using t-tests and c2 analysis. Differences in BP were analyzed using multivariate analysis of variance. Results: Two hundred seventy-five patients were included in our final analysis. Forty-eight percent of the patients underwent eCEA. Sixty percent of patients who underwent eCEA and 61% of patients who underwent cCEA were symptomatic. Thirty-day mortality was 1.4%, and 12-month mortality was 6.4% for the entire population. No statistical difference in perioperative stroke and restenosis rate was observed at 1-year follow-up.
Fig 1. Survival free of first readmission.
Fig 2. Overall patient survival.
gradients and resistance, while stenosis above 80% made significant contributions to these measurements. Unfortunately, stenoses above 80% also affected the renal resistance index, making it an unreliable index to confirm intrinsic renal artery disease. Conclusions: The intrinsic microvascular resistance of the kidney has a much greater effect on renal pressure gradients and resistances until renal stenosis is at least 80% for smooth plaque. Renal artery stenting of stenoses less than 80% may not significantly benefit most patients. With renal artery stenoses greater than 80%, the stenosis has a significant effect on renal pressures and resistances, but the renal resistance index is unreliable. Patients may benefit from renal artery stenting of lesions with more than 80% stenosis, but a better means of evaluating the functional reserve of the distal vasculature is needed than the current renal resistive index.
Fig. Renal pressures, flows, and resistances.
Author Disclosures: A. P. Sawchuk: None; W. Yu: None; A. Mumbaraddi: None; M. C. Dalsing: None. Novel Open Vascular Surgery Skills Training Model Accurately Differentiates Level of Vascular Surgical Skills (Forceps Handling, Needle Driving, and Knot Tying) in General Surgery Residents, Vascular Surgery Residents, Fellows, and Faculty Farah Mohammad, MD1, Loay Kabbani, MD2, Andrew Taylor2, Robert Cuff, MD3, John Rectenwald, MD3, Otto Brown, MD3, Carlo Dall’ Olmo, MD4, Mark Mattos, MD3. 1Department of General Surgery/ Vascular Surgery, Henry Ford Hospital, Detroit, Mich; 2Henry Ford Hospital, Detroit, Mich; 3Wayne State University Program, Detroit, Mich; 4Genesys Regional Medical Center, Flint, Mich Objectives: The aim of this study was to determine if the use of a novel low-fidelity simulated vascular skills training model could differentiate levels of vascular surgical skills in general and vascular surgery residents, vascular surgery fellows, and vascular surgery faculty. Methods: Fifty-four participants from eight different surgical training programs with varying levels of experience were recruited to perform primary closure of a 5-cm longitudinal arteriotomy using a novel simulated training model. Each participant performed three primary closures. Participants were ranked into one of eight levels of experience defined by their training levels: 1 ¼ program year (PGY)-1 (n ¼ 12); 2 ¼ PGY-2 (n ¼ 6); 3 ¼ PGY-3 (n ¼ 10); 4 ¼ PGY-4 (n ¼ 4); 5 ¼ PGY-5 (n ¼ 5); 6 ¼ PGY-6 (n ¼ 4); 7 ¼ PGY-7 (n ¼ 9); and 8 ¼ Faculty (n ¼ 4). Performance was assessed by task completion times, total global rating scale, suture placement accuracy, and number of needle drops and reloads. For each primary closure performance, a global rating summary score was assigned. All data was reported and evaluated based on the mean results of the three performance trials. Results: Mean task completion times decreased and total global rating scale and global rating summary scores increased in a linear fashion according to training level (P < .001). Linear regression analysis revealed that both task completion time and total global rating score could significantly predict level of training (P < .001). Suture placement accuracy, number of needle drops, and number of needle reloads were not predictive (P > .218). Conclusions: The results indicate that the training model and assessment metrics display construct validity over progressive years of surgical training at multiple training sites. Furthermore, the results support their
JOURNAL OF VASCULAR SURGERY September 2015
use as a helpful assessment tool for the evaluation of basic vascular surgery skills. Its value as a cost- and time-effective training model for the improvement of vascular surgery skills remains to be proven. Author Disclosures: F. Mohammad: None; L. Kabbani: None; A. Taylor: None; R. Cuff: None; J. Rectenwald: None; O. Brown: None; C. Dall’ Olmo: None; M. Mattos: None. Using Heat, Exercise, and Constrictive Pressure to Increase Vein Diameter and Arterial Flow in the Forearm Neelima Katragunta, Bradley Dixon, MD. Department of Vascular Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa Objectives: The major problem limiting use of arteriovenous fistulae (AVF) for dialysis is impaired fistula maturation. We seek to find out if perioperative vascular conditioning will improve AVF maturation. During the first phase of this study, we seek to determine the effects of heat, constrictive pressure, and hand exercises on cephalic vein diameter (CVD) and brachial artery blood flow (BAF) Methods: The patients underwent a baseline measurement of CVD and BAF in both arms at the on-site vascular laboratory at room temperature (23 C) with and without 30-mm Hg upper arm pressure cuff. They then underwent a 30-minute treatment of the left arm with a heating pad and constrictive upper arm pressure of 30 mm Hg along with intermittent hand exercise to determine the maximal attained brachial artery blood flow, cephalic vein diameter, and maximum tolerated skin temperature. The patients were brought in for a second visit where baseline BAF and CVD of left forearm were obtained. Measurements were repeated with 30-mm Hg constrictive pressure and heat and intermittent hand exercises. Measurements were obtained every 3 minutes for a total of 30 minutes. Results: The study group consisted of seven older patients with chronic kidney disease, 75% of who have vascular disease and a prior history of smoking, and half have diabetes. The results demonstrate that subjects tolerate a mean skin temperature of 101.6 F for 30 minutes. Heat alone caused an increase in BAF and CVD, but the greatest increase was when we combined heat, intermittent arm exercise, and upper arm pressure. We found that 30-mm Hg upper arm pressure reduced arm blood flow and increased CVD. If we added heat and intermittent hand exercise for 30 minutes, we could increase arm blood flow by more than three-fold over baseline and vein diameter by 19% (Figs 1 and 2). During the second visit, a two-fold increase of BAF and a13% increase in CVD over the baseline was demonstrated. Conclusions: Application of heat to the forearm and constrictive pressure to the upper arm in combination with intermittent hand exercises increases the CVD and the BAF. Whether 6 weeks of such preoperative
Fig 1. Variation in brachial artery (BA) flow.
Fig 2. Variation in cephalic vein (CV) diameter.
JOURNAL OF VASCULAR SURGERY Volume 62, Number 3
treatment will improve vein size and compliance, and whether this will translate into improvement in AVF maturation is to be determined by the next two phases of the study. Author Disclosures: N. Katragunta: None; B. Dixon: None.
Bacteriology and Treatment of Aortic Graft Infection: A Modern Perspective Loren L. Masterson, MD, Elizabeth Kudlaty, Lavina Malhotra, MD, Patricia Salvador, MD, Michael Go, MD. Department of Vascular Diseases and Surgery, The Ohio State University, Columbus, Ohio Objectives: Aortic graft infection after open repair is infrequent but morbid. In the endovascular era, prevalence of infected aortic grafts may be lower but outcomes no less severe. We reviewed recent infected aortic grafts at our institution to understand contemporary bacteriology and outcomes. Methods: All infected aortic grafts from 1996 through 2014 were reviewed. Surgeries, treatments, microbiology, and outcomes were collected. Results: A total of 34 cases were identified. Average age was 64 years, and 53% were men. Twenty-three (64%) had aortobifemoral bypass, seven (22%) had aortic tube graft, three (8%) had aortoiliac bypass, and one had aortopopliteal bypass. Indication for surgery was occlusive disease in 62% and aneurysm in 38%. Sixty-seven percent of patients had total graft removal, while 33% had partial removal. Fifteen patients had excision without reconstruction, 11 had simultaneous extraanatomic bypass, and eight had staged extra-anatomic bypass. Five patients with reconstruction developed infection of the new graft requiring removal. Three of these patients had their reconstruction done simultaneously with aortic graft removal, while two had their reconstruction staged after aortic graft removal. Thirty-one patients had culture results available: 11 had no growth, three grew candida, four grew staphylococcus, three grew streptococcus, five grew enterococcus, and eight grew multiple organisms. Thirtyday mortality after graft removal was 26%. Eight patients eventually came to amputation; three of these patients had a failed extra-anatomic bypass. Conclusions: Explantation and extra-anatomic bypass may still be considered standard treatment for aortic graft infection, but mortality and limb loss remain high. Bacterial species are heterogeneous and many infections are polymicrobial. Tailoring contemporary available treatments including medical management, excision without reconstruction, partial excision, and deep-vein or antibiotic-soaked graft inline reconstruction as cases permit are all reasonable given the morbidity of standard treatment.
Abstracts 823
Analysis of BP did not yield a significant difference between preoperative, 30-day, and 12-month follow-up measurements (P ¼ .893; systolic BP). There was no significant change to number and type of BP medications preoperatively, at 30 days, or at 12 months (P ¼ .145). Conclusions: eCEA has no significant short- or long-term effects on BP or number of BP medications compared with cCEA. Author Disclosures: B. C. Adams: None; M. R. Pedersen: None; M. S. Hosn: None; T. F. Kresowik: None; L. Pascarella: None. Long-Term Health Care Utilization Analysis of Open and Endovascular Abdominal Aortic Aneurysm Repair Emily A. Wood, MD, Manju Kalra, MD, Peter Gloviczki, MD, Audra A. Duncan, MD, Gustavo S. Oderich, MD, Mark D. Fleming, MD, Randall R. De Martino, MD, William S. Harmsen, Thomas C. Bower, MD. Mayo Clinic, Rochester, Minn Objectives: The Open versus Endovascular Repair Veterans Affairs Cooperative Study (OVER) demonstrated that total health care costs are not significantly different between the open (OR) and endovascular (EVAR) abdominal aortic aneurysm (AAA) repair out to 2 years. The aim of this study was to evaluate initial and long-term health care resource utilization of OR and EVAR in a non-Veterans Affairs, non-trial study population. Methods: Data from patients undergoing AAA repair between January 1, 2007 and December 31, 2009 at a single institution were obtained from a prospectively maintained database and retrospectively analyzed. Follow-up information was collected through January 15, 2015. Results: There were 475 patients (293 EVAR, 182 OR); OR patients were significantly younger (71 vs 77 years; P < .0001) and more often female (20% vs 10%; P ¼ .014). Median length of stay was significantly lower following EVAR: 2 days (range, 1-34 days) vs 7 days (range, 3-89 days) for OR (P < .00001). Mortality at 30 days for EVAR/OR was 0.7/0.5; median follow-up was 5.1/5.5 years. Eighty percent of EVAR and 75% of OR patients had a least one follow-up surveillance visit; 78% and 64% at least
Author Disclosures: L. L. Masterson: None; E. Kudlaty: None; L. Malhotra: None; P. Salvador: None; M. Go: None. The Long-Term Effects of the Type of Carotid Endarterectomy on Blood Pressure Brian C. Adams, MD, Mark R. Pedersen, MD, Maen S. Hosn, MD, Timothy F. Kresowik, MD, Luigi Pascarella, MD. University of Iowa Hospitals and Clinics, Iowa City, Iowa Objectives: Carotid endarterectomy (CEA) has been one of the most studied and scrutinized operative procedures in vascular surgery. Retrospective series and randomized trials have shown no difference in perioperative stroke and long-term restenosis between conventional patch angioplasty (cCEA) and eversion (eCEA). A number of authors have shown acute hemodynamic disturbances in the immediate postoperative period leading to a temporary hypertensive state. eCEA may increase the risk of postoperative hypertension due to the more extensive dissection of the carotid bulb. Studies have documented this hypertensive phenomenon in the immediate postoperative period; however, there is little data found evaluating the longterm effects. The objective of this study is to evaluate the hemodynamic disturbances following eCEA vs cCEA at short- and long-term follow-up. Methods: A retrospective review of patients who underwent CEA between July 1, 2009 and June 30, 2014 was conducted at our institution. Demographics, comorbidities, blood pressure (BP), and number and type of antihypertensive medications were collected preoperatively, at 30 days, and at 12 months. The differences in BP and medications between cCEA and eCEA patients were compared. Demographic data and comorbidities were compared using t-tests and c2 analysis. Differences in BP were analyzed using multivariate analysis of variance. Results: Two hundred seventy-five patients were included in our final analysis. Forty-eight percent of the patients underwent eCEA. Sixty percent of patients who underwent eCEA and 61% of patients who underwent cCEA were symptomatic. Thirty-day mortality was 1.4%, and 12-month mortality was 6.4% for the entire population. No statistical difference in perioperative stroke and restenosis rate was observed at 1-year follow-up.
Fig 1. Survival free of first readmission.
Fig 2. Overall patient survival.