Skeletal Muscle Bioenergetics in Critical Limb Ischemia and Diabetes

INTRODUCTION

Mitochondrial dysfunction is implicated in the metabolic myopathy accompanying peripheral artery disease (PAD) and critical limb ischemia (CLI). Type-2 diabetes mellitus (T2DM) is a major risk factor for PAD development and progression to CLI and may also independently be related to mitochondrial dysfunction. We set out to determine the effect of T2DM in the relationship between CLI and muscle mitochondrial respiratory capacity and coupling control.

METHODS

We studied CLI patients undergoing revascularization procedures or amputation, and non-CLI patients with or without T2DM of similar age. Mitochondrial respiratory capacity and function were determined in lower limb permeabilized myofibers by high-resolution respirometry.

RESULTS

Fourteen CLI patients (65 ± 10y) were stratified into CLI patients with (n = 8) or without (n = 6) T2DM and were compared to non-CLI patients with (n = 18; 69 ± 5y) or without (n = 19; 71 ± 6y) T2DM. Presence of CLI but not T2DM had a marked impact on all mitochondrial respiratory states in skeletal muscle, adjusted for the effects of sex. Leak respiration (State 2, P < 0.025 and State 4o, P < 0.01), phosphorylating respiration (P < 0.001), and maximal respiration in the uncoupled state (P < 0.001), were all suppressed in CLI patients, independent of T2DM. T2DM had no significant effect on mitochondrial respiratory capacity and function in adults without CLI.

CONCLUSIONS

Skeletal muscle mitochondrial respiratory capacity was blunted by ∼35% in patients with CLI. T2DM was not associated with muscle oxidative capacity and did not moderate the relationship between muscle mitochondrial respiratory capacity and CLI.

Emergency Management of Complicated Jejunal Diverticulosis

Jejunal diverticulosis is a rare condition that is usually found incidentally. It is most often asymptomatic but presenting symptoms are nonspecific and include abdominal pain, nausea, diarrhea, malabsorption, bleeding, obstruction, and/or perforation. A retrospective review of medical records between 1999 and 2012 at a tertiary referral center was conducted to identify patients requiring emergency management of complicated jejunal diverticulosis. Complications were defined as those that presented with inflammation, bleeding, obstruction, or perforation. Eighteen patients presented to the emergency department with acute complications of jejunal diverticulosis. Ages ranged from 47 to 86 years (mean, 72 years). Seven patients presented with evidence of free bowel perforation. Six had either diverticulitis or a contained perforation. The remaining five were found to have gastrointestinal bleeding. Fourteen of the patients underwent surgical management. Four patients were successfully managed nonoperatively. As a result of the variety of presentations, complications of jejunal diverticulosis present a diagnostic and therapeutic challenge for the acute care surgeon. Although nonoperative management can be successful, most patients should undergo surgical intervention. Traditional management dictates laparotomy and segmental jejunal resection. Diverticulectomy is not recommended as a result of the risk of staple line breakdown. The entire involved portion of jejunum should be resected when bowel length permits.

Mitochondrial Bioenergetics in the Metabolic Myopathy Accompanying Peripheral Artery Disease

Peripheral artery disease (PAD) is a serious but relatively underdiagnosed and undertreated clinical condition associated with a marked reduction in functional capacity and a heightened risk of morbidity and mortality. The pathophysiology of lower extremity PAD is complex, and extends beyond the atherosclerotic arterial occlusion and subsequent mismatch between oxygen demand and delivery to skeletal muscle mitochondria. In this review, we evaluate and summarize the available evidence implicating mitochondria in the metabolic myopathy that accompanies PAD. Following a short discussion of the available in vivo and in vitro methodologies to quantitate indices of muscle mitochondrial function, we review the current evidence implicating skeletal muscle mitochondrial dysfunction in the pathophysiology of PAD myopathy, while attempting to highlight questions that remain unanswered. Given the rising prevalence of PAD, the detriment in quality of life for patients, and the associated significant healthcare resource utilization, new alternate therapies that ameliorate lower limb symptoms and the functional impairment associated with PAD are needed. A clear understanding of the role of mitochondria in the pathophysiology of PAD may contribute to the development of novel therapeutic interventions.

It depends on your perspective: Resident satisfaction with operative experience

INTRODUCTION

Resident satisfaction is a key performance metric for surgery programs; we studied factors influencing resident satisfaction in operative cases, and the concordance of faculty and resident perceptions on these factors.

METHODS

Resident and faculty were separately queried on satisfaction immediately following operative cases. Statistical significance of the associations between resident and faculty satisfaction and case-related factors were tested by Chi-square or Fisher's exact test.

RESULTS

Residents and faculty were very satisfied in 56/87 (64%) and 36/87 (41%) of cases respectively. Resident satisfaction was associated with their perceived role as surgeon (p < 0.04), performing >50% of the case (p < 0.01), autonomy (p < 0.03), and PGY year 4-5(p < 0.02). Faculty taking over the case was associated with both resident and faculty dissatisfaction. Faculty satisfaction was associated with resident preparation (p < 0.01), faculty perception of resident autonomy (p < 0.01), and faculty familiarity with resident's skills (p < 0.01).

CONCLUSIONS

Resident and faculty satisfaction are associated with the resident's competent performance of the case, suggesting interventions to optimize resident preparation for a case or faculty's ability to facilitate resident autonomy will improve satisfaction with OR experience.

Elimination of pneumothorax and hemothorax during placement of implantable venous access ports using ultrasound and fluoroscopic guidance

Implantable venous access ports are essential for patients requiring chronic venous access. Ultrasound guided catheter placement has been recognized as a valuable adjunct for reducing complications during placement of access ports in the radiology and critical care medicine literature. We reviewed the medical records of patients undergoing insertion of implantable venous access ports from June 2006 through June 2009. All procedures were performed using ultrasound guidance with the internal jugular vein as the access site. There were 500 implantable venous access ports placed and included for review. There were no post-procedure pneumothoraces or hemothoraces. Carotid puncture was documented in 4 (0.8%)cases. Routine use of ultrasound guidance during placement of implantable venous access ports has eliminated the complications of pneumothorax and hemothorax during placement of internal jugular venous access ports on our vascular surgery service. Elimination of these complications and decreased use of chest x-rays should also provide increased cost savings for this procedure.

Emergency management of complicated jejunal diverticulosis

Jejunal diverticulosis is a rare condition that is usually found incidentally. It is most often asymptomatic but presenting symptoms are nonspecific and include abdominal pain, nausea, diarrhea, malabsorption, bleeding, obstruction, and/or perforation. A retrospective review of medical records between 1999 and 2012 at a tertiary referral center was conducted to identify patients requiring emergency management of complicated jejunal diverticulosis. Complications were defined as those that presented with inflammation, bleeding, obstruction, or perforation. Eighteen patients presented to the emergency department with acute complications of jejunal diverticulosis. Ages ranged from 47 to 86 years (mean, 72 years). Seven patients presented with evidence of free bowel perforation. Six had either diverticulitis or a contained perforation. The remaining five were found to have gastrointestinal bleeding. Fourteen of the patients underwent surgical management. Four patients were successfully managed nonoperatively. As a result of the variety of presentations, complications of jejunal diverticulosis present a diagnostic and therapeutic challenge for the acute care surgeon. Although nonoperative management can be successful, most patients should undergo surgical intervention. Traditional management dictates laparotomy and segmental jejunal resection. Diverticulectomy is not recommended as a result of the risk of staple line breakdown. The entire involved portion of jejunum should be resected when bowel length permits.

Bilateral Pulmonary Emboli Secondary to Indwelling Hemodialysis Reliable Outflow Catheter

We present a 33-year-old dialysis-dependent female who presented with new onset split second heart sound. Following a failed left upper extremity dialysis fistula, a right upper extremity hemodialysis reliable outflow (HeRO) graft was performed in 2011. Her subsequent cadaveric renal transplant had delayed function necessitating concurrent use of hemodialysis. However, as renal function improved, hemodialysis was discontinued. Two weeks following transplantation, the HeRO graft occluded. Subsequent clinical and radiological assessment confirmed widespread pulmonary emboli. Following cessation of hemodialysis and subsequent HeRO graft occlusion, removal was deemed appropriate to reduce further thromboembolic phenomenon. Right atrial thrombi are complications associated with central venous catheters. However, their actual incidence varies significantly. Right heart thromboemboli are associated with a 4% to 6% pulmonary embolism rate. Katzman et al assessed 38 patients who underwent HeRO graft and reported 1 (2.6%) patient with right atrial emboli and likely pulmonary embolism. Although thrombotic complications remain rare, consideration of graft removal should always be evaluated particularly in the absence of an alternative thrombotic source.

Vascular medicine: aortic and peripheral arterial disease

The medical management of patients with an abdominal aortic aneurysm (AAA) includes modification of risk factors, smoking cessation, cardiovascular risk treatment, and hypertensive therapy. No specific therapy has been shown to alter disease outcome. Many AAA and thoracic aortic aneurysms are amenable to endovascular treatment. Endovascular repair offers the benefit of shorter hospital stays and lower perioperative morbidity and mortality. Most patients with peripheral arterial disease (PAD) are asymptomatic or have atypical symptoms; only a few present with classic intermittent claudication or critical limb ischemia. Smoking and diabetes mellitus are the most important risk factors for developing PAD.

The minimally invasive management of visceral artery aneurysms and pseudoaneurysms

OBJECTIVE

Minimally invasive methods (MIMs) are now available for the management of visceral artery aneurysms and pseudoaneurysms (visceral artery aneurysms [VAA]). The purpose of this study was to review our 10-year experience with the MIM of treating VAA.

METHODS

All patients evaluated from June 1999 to June 2009 with VAAs were reviewed. Demographics, therapy, and results were analyzed.

RESULTS

MIM was attempted in 185 aneurysms in 176 patients. Initial intervention was successful in 98% ofaneurysms. Sixty-three (34%) aneurysms were located in the splenic artery, 56 (30%) in the hepatic, 28 (15%) in the gastroduodenal, 16 (8.6%) in the pancreaticoduodenal, six (3.2%) in the superior mesenteric, four (2.1%) in the gastric, four (2.1%) in the celiac, four (2.1%) in the gastroepiploic, two (1%) in the inferior mesenteric, and one (0.5%) in the middle colic artery. Pseudoaneurysms were more common than true aneurysms (64% vs 36%). Bleeding was the indication for intervention in 86 aneurysms (46%). Initial treatment was successful in 177 aneurysms (98%). Reintervention was required in five (3%) aneurysms within 30 days. Coiling was used alone in 139 aneurysms (75%) and in combination with at least one other technique in 20 (11%) cases. Thirty-day aneurysm-related mortality was 3.4% (six deaths). Five additional deaths occurred during 30-day follow-up, although none was related to complications of the aneurysms (2.8%).

CONCLUSIONS

MIM for visceral artery aneurysms can be used alone or in combination to effectively treat VAAs in elective or emergent conditions.