Omental Flap Coverage for Management of Thoracic Aortic Graft Infection

Mediastinal transposition of the greater omentum for treatment of infected prostheses of the ascending aorta and aortic arch

OBJECTIVES

The aim of this study was to evaluate the outcomes of transposition of the omentum into the mediastinum to support the replacement of infected aortic grafts or to cover infected aortic grafts that are not amenable for surgical replacement.

METHODS

All patients with thoracic aortic graft infections who underwent mediastinal transposition of the omentum at our institution between 2005 and 2023 were included in this study. Mediastinal transposition of the omentum was performed either after replacement of the infected graft ('curative concept') or solely as bailout procedure by wrapping the infected graft ('palliative concept'). The diagnosis, including computed tomography scans during follow-up, was made according to the criteria of the Management of Aortic Graft Infection Collaboration.

RESULTS

The patient cohort consisted of 31 patients. Both in-hospital and 1-year mortality were 0% (n = 0) for the curative concept (n = 9) compared to 23% (n = 5) and 41% (n = 9) for the palliative concept (n = 22), respectively. There was no graft infection-associated death or recurrence of infection after 3 years in the curative group. Survival was 52% at 3 years in the palliative group, with freedom of infection in 59% of the patients (n = 13).

CONCLUSIONS

Transposition of the omentum and wrapping of the infected aortic prosthetic graft is a useful bailout strategy for patients who are ineligible for replacement of an infected aortic graft. However, mortality stays high. For radical treatment of aortic graft infections, it may prove an effective supportive therapy and represents an important tool in the armamentarium of cardiac surgeons.

Laparoscopic harvest and free transplantation of great omentum flap for extensive tissue defects in complex wounds

INTRODUCTION

The repair of extensive tissue defects remains a challenge, although great progress has been made in reconstructive surgery. The transplantation of a single huge flap or several flaps in combination will inevitably result in donor-site morbidity. Here we report our experience in the repair of these wounds with laparoscopically harvested great omentum flaps.

METHODS

Twelve patients with extensive tissue defects caused by deep burn injury, avulsion injury, and open fracture underwent free omental flap transplantation and split-thickness skin grafting. The patient demographics, wound characteristics, and complications postsurgical operation were recorded. Prior to omentum flap transplantation, these patients underwent debridement, vacuum sealing drainage treatment, and/or fixation of fractures. All omentum flaps harvested using laparoscopic technique were anastomosed to recipient vessels, and split-thickness skin grafting was performed 14 days after omental flap transplantation.

RESULTS

The mean defect size was 471 cm2 and the mean omental flap size was 751.1 cm2. Among all 12 cases, the omental flaps survived well except for distal partial necrosis in one case. Skin grafting was also achieved in all cases, and all patients achieved complete wound coverage. All donor sites achieved primary healing without major complications. The mean follow-up time was 30 months with satisfactory appearance and functional outcome.

CONCLUSION

For the reconstruction of extensive tissue defects in complex wounds, the free transfer of an omental flap may be an ideal option because of its well-vascularized and pliable tissue with reliable vascular anatomy, as well as minimized donor-site morbidity.

Omental Flap for Complex Sternal Wounds and Mediastinal Infection Following Cardiac Surgery

INTRODUCTION

Omental flap (OF) is a traditional surgical option to counteract severe postcardiotomy mediastinal infection and to cover extensive sternal defects. We reviewed our experience with omental flap transfer (OFT) in various clinical circumstances, in which omentoplasty may be considered by cardiac surgeons.

METHODS

Twenty-one patients, who underwent OFT from January 2012 to December 2021, were studied. The main indication was treatment of infected foreign material implants including vascular grafts and ventricular assist devices or prevention of its infection (16 patients). In five patients, an OFT was used to cure mediastinitis following deep sternal wound infection after median sternotomy.

RESULTS

All patients had a high surgical risk with 3 ± 1.9 previous sternotomies and a mean Euro Score II of 55.0 ± 20.1. OF was successful in its prophylactic or therapeutic purpose in all patients, no complications related to the operative procedure were noted, that is, no early or late flap failure and no herniation of abdominal organs occurred. In-hospital mortality was six patients as three patients each died from multiple organ dysfunction syndrome and cerebral hemorrhage. All fifteen patients discharged demonstrated rapid recovery, complete wound healing without fistula, and no late gastrointestinal complications. The mean follow-up of 18 months was uneventful.

CONCLUSION

OFT seems to be an excellent solution for extensive mediastinal and deep sternal wound infections.

Robotic-assisted closed-chest management of a fungal-infected prosthetic aortic graft: a case report

Background

Fungal prosthetic graft infections are associated with high mortality, typically requiring aggressive surgical debridement. We present an alternative, minimally invasive approach to address these challenging clinical cases.

Case presentation

A 76-year-old Caucasian male with prior aortic root and arch replacement presented with localized chest wall tenderness after being hit by a car door. Computed tomography angiogram incidentally identified fluid in the anterior mediastinum, surrounding his ascending aortic graft. Rather than undertaking a high-risk reoperative sternotomy and redo complex aortic reconstruction, we elected to proceed with a robotic-assisted, minimally invasive debridement of the aortic graft, coupled with an omental wrap, entirely within the closed chest. Microbiology was positive for Aspergillus species. The patient made an uncomplicated recovery and was discharged home on antifungal therapy, likely to continue indefinitely.

Conclusions

Infected prosthetic aortic grafts can be successfully managed with debridement and pedicled omental flap coverage via a minimally invasive approach within the closed chest, obviating the morbidity of a complex reoperative open procedure.

In patients with thoracic aortic graft infection, is graft explantation and replacement superior to in situ graft preservation?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether graft explantation and replacement are superior to graft preservation in patients with thoracic aortic graft infections. Altogether, more than 487 papers were found using the reported search; of these, 7 comparative studies represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. Although thoracic aortic graft infection is uncommon following cardiac surgery, it still carries a significant risk of in-hospital mortality and poor long-term survival. Current findings in the literature are limited to retrospective cohort studies with relatively small sample sizes; also, there is a lack of randomized controlled trials on this topic. There was significant heterogeneity in patient groups and variation in surgical techniques across centres. In this context, a graft-sparing approach may be a safe therapy with comparable early mortality and late survival outcomes in carefully selected patients. The selection may include the absence of graft pseudoaneurysm, anastomotic leak and fistula; the presence of indolent infection in patients with poor clinical conditions; and significant frailty and comorbidities where the risks of surgical explantation exceed the benefits. The rate of reinfection is low following both graft replacement and the graft-sparing approach. Moreover, the use of a tissue flap improves the surgical outcomes.

The role of the pedicle omental flap in ruptured abdominal aortic aneurysm: a case report and literature review

A ruptured infrarenal abdominal aortic aneurysm (rAAA) is associated with an in-hospital mortality rate of 40% and an overall mortality rate of 60–80%. Open surgical repair for rAAA remains the principal method of treatment when endovascular repair is not available. Graft infection occurs in 1–4% of patients at 5 years, with a high incidence following emergency treatment. Other graft-related complications include pseudoaneurysm, graft occlusion and aorto-enteric fistula. This case report describes a 66-year-old male patient that was admitted to hospital complaining of intense abdominal pain, low blood pressure and tachycardia. He was diagnosed with a rAAA and treated using segmental resection of the abdominal aorta followed by reconstruction with a synthetic Dacron prosthesis. A pedicle omental flap was wrapped around the prosthetic graft and it was also used to fill the retroperitoneal cavity in order to reduce the risk of graft-related complications. Computed tomography angiography after 6 months showed good integration of the aortic prosthetic graft and the viability of the omental flap. In our opinion, vascular surgeons should consider the pedicle omental flap when they perform open surgical repair for rAAA in order to reduce the incidence of graft-related complications.

Y-shaped Muscular Wrapping Technique Avoiding Re-infection of a Replaced Aortic Graft: A Cadaveric Study

Replacing an infected prosthetic thoracic aorta graft carries a high re-infection risk. We previously reported two clinical cases successfully treated with a new muscular wrapping technique: latissimus dorsi (LD) muscle flap with a distally based serratus anterior (SA) extension; however, a cadaveric study to prove the regular existence of the distal attachment area was lacking. We tried to establish an appropriate way of elevating the combined muscle flap safely. All of the cadavers were preserved using the Thiel embalming technique to retain flexibility. We checked for the existence of the distal attachment area between the LD and SA. Combined muscle flaps were elevated proximally while identifying the thoracodorsal artery, including the LD and SA branches. After the SA branch was ligated and cut, the SA muscle was manually peeled from the LD muscle with only the distal tight attachment area remaining. Contrast-enhanced computed tomography was performed using a multislice computed tomography system. Six human cadavers (three men, three women: 91 years old, on average) were examined. All six LD and SA combined muscle flaps showed a distal tight attachment area at the level from the seventh rib to the ninth rib. The tip of the SA muscle easily reached the sternum. Contrast-enhanced computed tomography failed to reconfirm the distal vascular flow from the LD to the reverse SA muscle, which we had visualized in a clinical case. We demonstrated the anatomical reliability of the new Y-shaped muscular flaps, which are suitable for preventing re-infection of aortic graft replacement.

The impact of vascularized tissue flap coverage on aortic graft infection with and without infected graft excision

OBJECTIVES

Aortic graft infection (AGI) is a serious condition associated with a high mortality rate. However, optimal surgical options have not been identified. Therefore, we retrospectively reviewed AGI cases, including those in the thoracic and abdominal regions, with or without fistula formation, to investigate the various options for better outcomes.

METHODS

We reviewed 50 patients who underwent surgical interventions for AGI out of 97 patients with arterial infective disease. The mean patient age was 67 ± 17 years. Fourteen patients (28%) had a fistula with the gastrointestinal tract or lung. A combination of graft excision and vascularized tissue flap coverage was performed in 25 cases (50%). Tissue flap alone, graft excision alone and cleansing alone were performed in 9 (18%), 10 (20%), and 6 cases (12%), respectively.

RESULTS

Total in-hospital mortality rate was 32% (n = 16). In-hospital mortalities in patients with and without fistulas were 43% (6/14) and 28% (10/36), respectively (P = 0.33). Subgroup analysis among patients without fistula demonstrated that the in-hospital mortality rate of the patients with vascularized tissue flap (3/21, 14%) was significantly lower than that of the patients without vascularized tissue flap (7/14, 50%, P = 0.026). Overall 1- and 5-year survival rates were 66% and 46%, respectively. In multivariable analysis, an independent factor associated with in-hospital mortality was vascularized tissue flap (odds ratio 0.20, P = 0.024).

CONCLUSIONS

Vascularized tissue flaps could provide better outcomes for AGI. Graft preservation with vascularized tissue flaps could be a useful option for AGI without fistula.

Pasteurella Multiocida infection resulting in a descending thoracic aorta mycotic pseudoaneurysm

OBJECTIVE

Highlight our management of a Pasteurella Multiocida-infected descending thoracic aorta mycotic pseudoaneurysm.

METHODS

Report a case of a canine bite resulting in a P. Multiocida descending thoracic aorta mycotic pseudoaneurysm.

RESULTS

We present a 61-year-old gentleman who was initially seen in an emergency department after a canine bite. He was admitted and treated with a course of IV antibiotics for P. Multiocida bacteremia and discharged. Three weeks after discharge, he continued to feel generalized malaise and work-up was significant for a descending thoracic aorta mycotic pseudoaneurysm. The patient underwent a low left posterior lateral thoracotomy and femoral-femoral cardiopulmonary bypass for complete pseudoaneurysm resection and aortic replacement with a 24-mm Gelweave graft. Given purulence and gross infection, we planned for a staged approach, with a secondary washout and omental flap for biologic coverage of the graft. The patient did well clinically and was discharged at 14 days to rehabilitation with 6-week intravenous course of antibiotics.

CONCLUSIONS

The patient's clinical course with subsequent follow-up suggest that complete resection of the mycotic pseudoaneurysm, followed by omental flap coverage is a viable strategy to manage mycotic aortic infections with virulent organisms.