Temporary extracorporeal femoro-femoral crossover bypass to treat critical limb ischemia due to occlusive femoral transaortic microaxial left ventricular assist device – a novel technique and case series

Objective

The Impella transaortic microaxial left ventricular assist device (MLVAD) bears the risk of severe ipsilateral limb ischemia due to it´s percutaneous insertion through the common femoral artery (CFA). As long as the MLVAD is required for cardio-circulatory support, treatment options are limited. Therefore, we developed a temporary extracorporeal femoro-femoral crossover bypass to restore and maintain perfusion of the affected leg.

Methods

From October 2018, we treated all patients with severe limb ischemia due to the MLAVD with a femoro-femoral crossover bypass. For comparison, a consecutive cohort of patients undergoing placement of the MLAVD between January 2011 and July 2019 was identified.

For those patients who experienced limb ischemia after Impella placement, data on age, gender, BMI and diabetes, underlying cardiac condition, duration of Impella pump in place, limb complications, limb salvage procedure, need for additional surgical procedure on the affected limb (e.g. fasciotomy) were recorded.

The primary outcome is the feasibility and safety of our percutaneously established extracorporeal femoro-femoral crossover bypass. As secondary outcomes, we report overall 30 day mortality and limb salvage rates.

Results

Between January 2011 and July 2019, 25 of 245 (10.3%) patients developed a severe ipsilateral limb ischemia following the MLVAD placement.

Until October 2018, 20 patients were treated conventionally (C-cohort) and since October 2018, five (consecutive) patients have been treated by an extracorporeal femoro-femoral cross over bypass (BP-Cohort).

Following the BP-procedure, an immediate improvement of the perfusion was seen in all patients. The bypass remained in place during a median of 5 days. Limb salvage was documented in 100% of our patients and 30 days mortality was 60% in both groups.

Conclusion

This is the first case series reporting on this novel technique. We demonstrated that the percutaneous creation of an extracorporeal femoro-femoral crossover bypass is feasible, safe and effective and should therefore be promoted in the future.

Early-cannulation arteriovenous grafts are safe and effective in avoiding recurrent tunneled central catheter infection

Objective

Tunneled central venous catheter infection (TCVCi) is a common complication that often necessitates removal of the TCVC and a further TCVC. Theoeretically, insertion of an early-cannualtion graft (ecAVG) early after TCVC infection is possible but not widely practiced with concerns over safety and infection in the ecAVG. With 8 years of ecAVG experience, the aim of this study was to compare the outcomes following TCVC infection, comparing replacement with TCVC (TCVCr) versus immediate ecAVG (ecAVGr).

Methods

Retrospective comparison of two cohorts, who underwent replacement of an infected TCVC either by an early cannulation graft (n = 18) or by a further central catheter (n = 39).

Data were abstracted from a prospectively completed electronic patient record and collected on patient demographics, TCVC insertion, duration and infection, including culture proven bacteriaemia and subsequent access interventions.

Results

18/299 patients identified from 2012-2020 had an ecAVG implanted as treatment for a TCVCi. In a one-year time-period (1/1/2015 -31/12/2015) out of 222 TCVC inserted, 39 were as a replacement following a TCVCi. No patient with an ecAVGr developed an immediate infection, nor complication from the procedure. The rate of subsequent vascular access infection was significantly more frequent for those with TCVCr than with an ecAVGr (0.6 vs. 0.1/patient/ 1000 HD days, p < 0.000). The number of further TCVC required was significantly higher in the TCVCr group (7.1 vs. 0.4/patient/ 1000 HD days, p = 0.000).

Conclusion

An ecAVG early following a TCVC infection is safe, reduces the incidence of subsequent infectious complications and reduces the number of TCVC required, with a better functional patency.

Patient characteristics predict patency of early-cannulation arteriovenous grafts

There is a new emphasis on tailoring appropriate vascular access for hemodialysis to patients and their life-plans, but there is little known about the optimal use of newer devices such as early-cannulation arteriovenous grafts (ecAVG), with studies utilising them in a wide variety of situations. The aim of this study was to determine if the outcome of ecAVG can be predicted by patient characteristics known pre-operatively. This retrospective analysis of 278 consecutive ecAVG with minimum one-year follow-up correlated functional patency with demographic data, renal history, renal replacement and vascular access history. On univariate analysis, aetiology of renal disease, indication for an ecAVG, the number of previous tunnelled central venous catheters (TCVC) prior to insertion of an ecAVG, peripheral vascular disease, and BMI were significant associates with functional patency. On multivariate analysis the number of previous TCVC, the presence of peripheral vascular disease and indication were independently associated with outcome after allowing for age, sex and BMI. When selecting for vascular access, understanding the clinical circumstances such as indication and previous vascular access can identify patients with differing outcomes. Importantly, strategies that result in TCVC exposure have an independent and cumulative association with decreasing long-term patency for subsequent ecAVG. As such, TCVC exposure is best avoided or minimised particularly when ecAVG can be considered.

Early-Cannulation Arteriovenous Grafts Are Safe and Effective in Avoiding Recurrent Tunneled Central Catheter Infection

OBJECTIVES

Tunneled central venous catheter infection (TCVCi) is a common complication that often necessitates removal of the TCVC and replacement by a further TCVC. Theoretically, insertion of an early - cannulation graft (ecAVG) early after TCVC infection is possible but not widely practiced with concerns over safety and infection in the ecAVG. With 8 years of ecAVG experience, the aim of this study was to compare the outcomes following TCVC infection, comparing replacement with TCVC (TCVCr) versus immediate ecAVG (ecAVGr).

DESIGN

Retrospective comparison of 2 cohorts, who underwent replacement of an infected TCVC either by an early cannulation graft (n = 18) or by a further central catheter (n = 39).

METHODS

Data were abstracted from a prospectively completed electronic patient record and collected on patient demographics, TCVC insertion, duration and infection, including culture proven bacteriaemia and subsequent access interventions.

RESULTS

Eighteen of 299 patients identified from 2012 to 2020 had an ecAVG implanted as treatment for a TCVCi. In a 1-year time-period (January 1, 2015-December 31, 2015) out of 222 TCVC inserted, 39 were as a replacement following a TCVCi. No patient with an ecAVGr developed an immediate infection, nor complication from the procedure. The rate of subsequent vascular access infection was significantly more frequent for those with a TCVCr than with an ecAVGr (0.6 vs. 0.1/patient/1000 HD days, P< 0.000). The number of further TCVC required was significantly higher in the TCVCr group (7.1 vs. 0.4/patient/1000 HD days, P= 0.000).

CONCLUSIONS

An ecAVG early following a TCVC infection is safe, reduces the incidence of subsequent infectious complications and reduces the number of TCVC required, with a better functional patency.