Vascular surgery patients in intensive care: a bi-national cohort study over 15 years.

BACKGROUND: To describe the characteristics and outcomes of patients admitted to Intensive Care following vascular surgery, and their subsequent usage of Intensive Care resources, over a 15-year period in Australia and New Zealand. METHODS: This was a retrospective, bi-national study of 69 676 adult patients admitted to 179 Intensive Care Unit (ICUs) following vascular surgery between January 2005 and December 2019, using the Australian and New Zealand Intensive Care Society Adult Patient Database. RESULTS: The proportion of ICU bed days used by vascular surgery patients decreased during the study period from 3.6% in 2005 to 2.9% in 2019 (P < 0.001). The cohort had a median age of 73 years, and were most frequently admitted after a carotid endarterectomy (22%) or elective open aneurysm repair (20%). A total of 5.2% of patients did not survive to discharge. Mean annual adjusted mortality decreased during the study period from 6.1% in 2005 to 3.7% in 2019 (P < 0.001). Multiple factors were associated with higher mortality, including gender, hospital case volume and hospital type. CONCLUSIONS: Between 2005 and 2019 survival for vascular surgery patients requiring ICU admission in Australia and New Zealand improved. During the same time the proportion of ICU bed days used by these patients decreased.

Renocaval Bypass for Acute Renal Failure and Haematuria Following Left Renal Vein Ligation During Aorto-Bifemoral Bypass.

Ligation of the left renal vein is an accepted manoeuvre where it is difficult to access the pararenal abdominal aorta for the open treatment of aortic occlusive or aneurysmal disease. There is some controversy regarding the long-term effect of this on renal function. We describe the case of a 37-year-old gentleman who underwent an elective aorto-bifemoral bypass for aorto-iliac occlusive disease with symptoms of short distance claudication, with intra-operative ligation of the left renal vein. This was complicated by post-operative acute renal failure and haematuria, with CT findings of left renal venous dilatation and peri-renal stranding. The patient underwent successful left renocaval bypass with reversed great saphenous vein, with subsequent resolution of haematuria and improvement in renal function. The syndrome of acute renal failure and haematuria is a rare but possible complication of left renal vein ligation during aortic surgery, and restoration of renal venous outflow via renocaval bypass in this instance was an effective method of treating this complication.

Per- and polyfluoroalkyl substances (PFAS) in livestock and game species: A review.

Per- and polyfluoroalkyl substances (PFAS) are synthetic, organic chemicals that resist environmental breakdown. The properties that made PFAS into an industrial success also led to their persistence and bioaccumulation. As PFAS were widely used for many decades their presence is evident globally, and their persistence and potential for toxicity create concern for human, animal and environmental health. Following the precautionary principle, a reduction in human exposure is generally recommended. The most significant source of human exposure to PFAS is dietary intake (food and water) with additional exposure via dust. As PFAS concentrations have been more frequently studied in aquatic food sources, there is less understanding of exposure via terrestrial animals. To further define human exposure via animal products, it is necessary to determine PFAS concentrations and persistence in terrestrial livestock and game species. Studies assessing ambient concentrations of PFAS have noted that, aside from point sources of contamination, there is generally low input of PFAS into terrestrial agricultural food chains. However, livestock and game species may be exposed to PFAS via contaminated water, soil, substrate, air or food, and the contribution of these exposures to PFAS concentrations in food products is less well studied. This review focuses on perfluoroalkyl substances (PFAAs) and compiles information from terrestrial livestock and game species as a source of dietary exposure in humans, and discusses toxicokinetics and health effects in animals, while identifying future focus areas. Publications describing the transfer of PFAAs to farmed and hunted animals are scarce, and demonstrate large variability in distribution and elimination. We outline several relatively small, short-term studies in cattle, sheep, pigs and poultry. While negative effects have not been noted, the poultry investigations were the only studies to explicitly assess health effects. Comparative information is presented on PFAA concentrations in livestock products and edible tissues of game animals.

How to do it: a modified transabdominal wall approach for direct external iliac artery access during endovascular thoracic aneurysm repair.

We describe the combined application of a transabdominal wall sheath tunnel, 'pre-close' purse-string sutures and manual external support of the iliac artery to facilitate introduction of an 18F sheath for endovascular exclusion of a 6-cm thoracic aortic aneurysm.

Case of Segmental Arterial Mediolysis.

Segmental arterial mediolysis (SAM) is a rare, non-inflammatory, vascular condition that predominantly affects medium-sized to large-sized abdominal arteries and can present with haemorrhage into the abdominal cavity. We report the case of a patient with SAM of the coeliac, splenic, renal and gastroduodenal arteries in whom endovascular coil embolisation was successfully used to treat a bleeding gastroduodenal artery pseudoaneurysm.

Inner-Branched Endografts for the Treatment of Aortic Arch Aneurysms After Open Ascending Aortic Replacement for Type A Dissection.

BACKGROUND: The development of a postdissection aortic arch aneurysm after open ascending aortic replacement for type A dissection places the patient at increased risk for an open operation due to the need for redo sternotomy and total arch replacement. We conducted a computed tomography-based feasibility study to assess what proportion of these patients would be anatomically suitable for branched endograft repair of an arch aneurysm. We also aimed to identify ways to tailor the index operation to increase suitability for future endovascular repair. METHODS: Our study was conducted at the Aortic Centre, Lille University Hospital, Lille, France. Postoperative images were assessed for patients after open replacement of the ascending aorta for acute type A dissection in this center between 2009 and 2015 to determine suitability for use of an aortic arch inner-branched device. RESULTS: The assessment found 52 of 73 patients (71.2%) were anatomically suitable for treatment with the aortic arch inner-branched device. The only cause for absolute exclusion from suitability was the absence of a proximal landing zone in the ascending aorta. Reasons for this were the ascending aortic graft being too short (71.4%), the presence of a major kink in the graft (23.8%), and the graft diameter being too large (4.8%). CONCLUSIONS: Approximately 70% of patients with arch aneurysm formation after open ascending aortic replacement for type A dissection are anatomically suitable for treatment with the aortic arch inner-branched device. In the future, surgeons will be able to fashion the prosthetic graft at the time of the index operation to ensure it fulfills criteria for an adequate proximal landing zone.

Fresh arterial homograft for bypass in critical limb ischaemia with infection.

We present what we believe is Australia's first fresh peripheral arterial transplant for revascularisation of an ischaemic limb. Although cryopreserved homografts are accepted as a management option for revascularisation of critical limb ischaemia in infected fields, cryopreserved peripheral vascular tissue is not currently available in Australia. We describe a 72-year-old man without autologous conduit in whom infected prosthetic grafts were explanted, causing critical limb ischaemia of a below knee stump. Fresh peripheral arterial tissue was procured via the Australian organ donation authority, DonateLife, and was used to revascularise the stump with an axillofemoral bypass. This permitted successful healing of the stump within 6 weeks and mobilisation with a prosthesis. This case illustrates that fresh arterial homografts are a viable bridging solution for revascularisation of limb ischaemia with infection. However, it also highlights the need to establish a peripheral homograft bank so that cryopreserved conduits are readily available for similar scenarios.