A method for perfusion of the leg during cardiopulmonary bypass via femoral cannulation

Acute Limb Ischaemia during ECMO Support: A 6-Year Experience

The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock is rising. Acute limb ischaemia remains one of the main complications after ECMO initiation. We analysed 104 patients from our databank from January 2015 to December 2021 who were supported with mobile ECMO therapy. We aimed to identify the impact of acute limb ischaemia on short-term outcomes in patients placed on ECMO in our institution. The main indication for ECMO therapy was left ventricular (LV) failure with cardiogenic shock (57.7%). Diameters of arterial cannulas (p = 0.365) showed no significant differences between both groups. Furthermore, concomitant intra-aortic balloon pump (IABP, p = 0.589) and Impella (p = 0.385) implantation did not differ significantly between both groups. Distal leg perfusion was established in approximately 70% of patients in two groups with no statistically significant difference (p = 0.960). Acute limb ischaemia occurred in 18.3% of cases (n = 19). In-hospital mortality was not significantly different (p = 0.799) in both groups. However, the bleeding rate was significantly higher (p = 0.005) in the limb ischaemia group compared to the no-limb ischaemia group. Therefore, early diagnosis and prevention of acute limb ischaemia might decrease haemorrhage complications in patients during ECMO therapy.

Continuous near-infrared reflectance spectroscopy monitoring to guide distal perfusion can minimize limb ischemia surgery for patients requiring femoral venoarterial extracorporeal life support

BACKGROUND

Patients requiring femoral venoarterial (VA) extracorporeal life support (ECLS) are at risk of distal lower limb hypoperfusion and ischemia of the cannulated leg. In the present study, we evaluated the effect of using continuous noninvasive lower limb oximetry with near-infrared reflectance spectroscopy (NIRS) to detect tissue hypoxia and guide distal perfusion catheter (DPC) placement on the rates of leg ischemia requiring surgical intervention.

METHODS

We performed a retrospective analysis of patients who had undergone femoral VA-ECLS at our institution from 2010 to 2014 (pre-NIRS era) and 2017 to 2021 (NIRS era). Patients who had undergone cannulation during the 2015 to 2016 transition era were excluded. The baseline characteristics, short-term outcomes, and ischemic complications requiring surgical intervention (eg, fasciotomy, thrombectomy, amputation, exploration) were compared across the two cohorts.

RESULTS

Of the 490 patients included in the present study, 141 (28.8%) and 349 (71.2%) had undergone cannulation before and after the routine use of NIRS to direct DPC placement, respectively. The patients in the NIRS cohort had had a greater incidence of hyperlipidemia (53.7% vs 41.1%; P = .015) and hypertension (71.4% vs 60%; P = .020) at baseline, although they were less likely to have been supported with an intra-aortic balloon pump before ECLS cannulation (26.9% vs 37.6%; P = .026). These patients were also more likely to have experienced cardiac arrest (22.9% vs 7.8%; P ≤ .001) and a pulmonary cause (5.2% vs 0.7%; P = .04) as an indication for ECLS, with ECLS initiated less often for acute myocardial infarction (15.8% vs 34%; P ≤ .001). The patients in the NIRS cohort had had a smaller arterial cannula size (P ≤ .001) and a longer duration of ECLS support (5 vs 3.25 days; P ≤ .001) but significantly lower rates of surgical intervention for limb ischemia (2.6% vs 8.5%; P = .007) despite comparable rates of DPC placement (49.1% vs 44.7%; P = .427), with only two patients (1.1%) not identified by NIRS ultimately requiring surgical intervention.

CONCLUSIONS

The use of a smaller arterial cannula (≤15F) and continuous NIRS monitoring to guide selective insertion of DPCs could be a valid and effective strategy associated with a reduced incidence of ischemic events requiring surgical intervention.

Comparative clinical efficacy of novel bidirectional cannula in cardiac surgery via peripheral cannulation for cardiopulmonary bypass

OBJECTIVES

The aim of this study is to evaluate the safety and efficacy of the novel bidirectional cannula that ensures stable distal perfusion compared to conventional cannula in patients undergoing femoral arterial cannulation for cardiopulmonary bypass (CPB).

METHODS

During a 1-year period, 64 patients undergoing surgery via peripheral cannulation were prospectively randomized to receive 19 F bidirectional (Biflow™, LivaNova, Italy) or 19 F conventional (HLS Peripheral cannula, Getinge Group™, Germany) cannula with 6 F downstream line (Bicakcilar™, Turkey) for femoral artery cannulation. The primary outcome included the efficacy (adequacy of antegrade/retrograde comparative flow via cannula measured by doppler ultrasonography) and the secondary outcome was the safety (early/late complications and adverse events).

RESULTS

Percent flow (distal/proximal) after cannulation measured by doppler ultrasonography was significantly better in study group (33.1 ± 5 ml/min) versus downstream cannula (16.1 ± 4, p = 0.012). SpO₂ measured by near infrared spectroscopy (NIRS) also demonstrated significantly better saturation in distal calf of the cannulated leg in bidirectional cannula group (67.5% ± 10% vs 52.5 ± 8, p = 0.04). The incidence of serious adverse events was seroma on femoral region (one patient), superficial wound infection (one patient), pseudo-hematoma (two patients) in bidirectional cannula group and in-hospital femoral embolectomy/artery repair (two patients), superficial wound infection (three patients), cannulation site hematoma (three patients) in conventional cannula group.

CONCLUSIONS

This study demonstrates that in patients undergoing femoral arterial cannulation for CPB during cardiac surgery, the use of a novel bidirectional cannula is safe and easy to insert and provides stable distal perfusion of the cannulated limb.

Fast-Track Cardiac Anesthesia Aids in the Early Diagnosis of Lower Extremity Compartment Syndrome: A Case Report

A 21-year-old otherwise healthy male with severe asymptomatic mitral regurgitation underwent a mitral valve repair via right thoracotomy and right femoral cannulation for cardiopulmonary bypass. Due to his age and health status, the anesthetic was planned to facilitate early extubation. Immediately on arrival to the intensive care unit, the patient complained of severe right calf pain with decreased sensation of the plantar foot. He was diagnosed with compartment syndrome and was taken back to the operating room for emergent 4-compartment fasciotomy. The fast-track anesthetic allowed for early diagnosis and treatment and prevented a likely catastrophic outcome.

Utility of Ultrasonographic Assessment of Distal Femoral Arterial Flow during Minimally Invasive Valve Surgery

PURPOSE

To evaluate the utility of ultrasonographic assessment of blood flow to the lower limb below the cannulation site in minimally invasive cardiac surgery (MICS).

METHODS

Twenty-two patients who underwent ultrasonographic assessment in MICS were reviewed retrospectively. In all patients, the right femoral artery was used for arterial cannulation. Ultrasonographic assessment was performed using a 15-MHz ultrasonography small probe, and regional oxygen saturation was monitored by near-infrared spectroscopy (NIRS).

RESULTS

The mean flow velocity at the distal side of the cannulation site was 46.2 ± 25.4 cm/s. In six patients, a >40% decreased from baseline regional oxygen saturation was observed. In five of the six patients, the flow velocity was very slow, and spontaneous echo contrast was also observed in three cases. Their regional oxygen saturation was improved rapidly after distal leg perfusion. In the remaining case, the flow velocity was not decreased. In another one case, the stenosis at the cannulation site was detected after decannulation and repaired immediately. No limb ischemic complications were observed in this series.

CONCLUSION

Ultrasonographic assessment combined with the NIRS monitoring is useful to prevent lower limb ischemic complications after femoral arterial cannulation in MICS.

Joint Society of Critical Care Medicine-Extracorporeal Life Support Organization Task Force Position Paper on the Role of the Intensivist in the Initiation and Management of Extracorporeal Membrane Oxygenation

OBJECTIVES

To define the role of the intensivist in the initiation and management of patients on extracorporeal membrane oxygenation.

DESIGN

Retrospective review of the literature and expert consensus.

SETTING

Series of in-person meetings, conference calls, and emails from January 2018 to March 2019.

SUBJECTS

A multidisciplinary, expert Task Force was appointed and assembled by the Society of Critical Care Medicine and the Extracorporeal Life Support Organization. Experts were identified by their respective societies based on reputation, experience, and contribution to the field.

INTERVENTIONS

A MEDLINE search was performed and all members of the Task Force reviewed relevant references, summarizing high-quality evidence when available. Consensus was obtained using a modified Delphi process, with agreement determined by voting using the RAND/UCLA scale, with score ranging from 1 to 9.

MEASUREMENTS AND MAIN RESULTS

The Task Force developed 18 strong and five weak recommendations in five topic areas of extracorporeal membrane oxygenation initiation and management. These recommendations were organized into five areas related to the care of patients on extracorporeal membrane oxygenation: patient selection, management, mitigation of complications, coordination of multidisciplinary care, and communication with surrogate decision-makers. A common theme of the recommendations is extracorporeal membrane oxygenation is best performed by a multidisciplinary team, which intensivists are positioned to engage and lead.

CONCLUSIONS

The role of the intensivist in the care of patients on extracorporeal membrane oxygenation continues to evolve and grow, especially when knowledge and familiarity of the issues surrounding extracorporeal membrane oxygenation selection, cannulation, and management are applied.

Design optimization of bidirectional arterial perfusion cannula

Objectives

Determine if shortening the covered section of a self-expanding bidirectional arterial cannula, can enhance retrograde flow and thus reduce the risk of lower limb ischemia.

Methods

Outlet pressure vs flow rate was determined for three cannulas types: a 15F self-expanding bidirectional cannula having a covered section of 90 mm, the same cannula but with a shorter covered section of 60 mm, and a Biomedicus cannula as control. The performances of all the cannulas were compared using a computerized flow-bench with calibrated sensors and a centrifugal pump. Water retrograde flow was determined using a tank timer technique. Anterograde and retrograde flow rate versus outlet pressure were determined at six different pump speed.

Results

For each of the six pump speed, both bidirectional cannulas, 60-mm covered and 90-mm covered respectively, showed higher performance than Biomedicus cannula control, as demonstrated by higher flow rate and lower pressure. We also observed that for the bidirectional cannula with shorter covered section, i.e. 60 mm coverage, provides enhanced performance as compared to a 90-mm coverage. Finally, the flow rate and the corresponding pressure can be consistently measured by our experimental set-up with low variability.

Conclusions

The new configuration of a shorter covered section in a bidirectional self-expanding cannula design, may present an opportunity to overcome lower leg ischemia during extra-corporal life support with long term peripheral cannulation.

Minimally Invasive Aortic Valve Surgery in Octogenarians: Reliable Option or Fallback Solution?

OBJECTIVE

Aortic valve disease is more and more common in western countries. While percutaneous approaches should be preferred in older adults, previous reports have shown good outcomes after surgery. Moreover, advantages of minimally invasive approaches may be valuable for octogenarians. We sought to compare outcomes of conventional aortic valve replacement (CAVR) versus minimally invasive aortic valve replacement (MIAVR) in octogenarians.

METHODS

We retrospectively collected data of 75 consecutive octogenarians who underwent primary, elective, isolated aortic valve surgery through conventional approach (41 patients, group CAVR) or partial upper sternotomy (34 patients, group MIAVR).

RESULTS

Mean age was 81.9 ± 0.9 and 82.3 ± 1.1 years in CAVR and MIAVR patients, respectively (P = 0.09). MIAVR patients had lower 24-hour chest drain output (353.4 ± 207.1 vs 501.7 ± 229.9 mL, P < 0.01), shorter mechanical ventilation (9.6 ± 2.4 vs 11.3 ± 2.3 hours, P < 0.01), lower need for blood transfusions (35.3% vs 63.4%, P = 0.02), and shorter hospital stay (6.8 ± 1.6 vs 8.3 ± 4.3 days, P < 0.01). Thirty-day mortality was zero in both groups. Survival at 1, 3, and 5 years was 89.9%, 80%, and 47%, respectively, in the CAVR group, and 93.2%, 82.4%, and 61.8% in the MIAVR group, with no statistically significant differences (log-rank test, P = 0.35).

CONCLUSIONS

Aortic valve surgery in older patients provided excellent results, as long as appropriate candidates were selected. MIAVR was associated with shorter mechanical ventilation, reduced blood transfusions, and reduced hospitalization length, without affecting perioperative complications or mid-term survival.

Distal perfusion cannulae reduce extracorporeal membrane oxygenation-related limb ischemia

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a means of providing cardiopulmonary support that is being increasingly used in patients with acute heart failure. When ECMO cannulae are placed peripherally, their large diameters pose a risk of limb ischemia. Distal perfusion cannulae (DPC) have been proposed as means to reduce risk, but their use is not recommended by the most recent ECMO guidelines. We sought to establish their utility at our institution.

METHODS

We performed a retrospective review of of all patients treated with peripheral VA-ECMO at our institution from 2013-2018. During the first 2 years, DPC were not routinely placed, whereas in the final 4 years, DPC were recommended as part of the ECMO cannulation routine.

RESULTS

One hundred and one patients were treated with peripheral VA-ECMO, with an overall mortality of 61%. By univariate analysis, obesity (47% vs. 75%, P<0.01) and limb ischemia (57% vs. 83%, P<0.05) were associated with increased mortality. DPC were placed prophylactically in 49% of patients. Prophylactic placement of a DPC at the time of cannulation significantly reduced the incidence of limb ischemia (2% vs. 32%, P<0.05), but did not impact mortality (53% vs. 69%, P=0.0953). In patients who did not have a DPC placed during ECMO cannulation and subsequently developed limb ischemia, late DPC placement for limb salvage did not impact mortality.

CONCLUSIONS

Limb ischemia portends a poor outcome in VA-ECMO patients, and prophylactic DPC placement significantly reduces the risk of limb ischemia. We propose prophylactic DPC placement be considered in patients requiring peripheral VA-ECMO.

Comparison of the Efficacy of Transthoracic Cannulation into the Ascending Aorta Versus Femoral Artery Cannulation in Minimally Invasive Cardiac Surgery

Objective

To delineate the efficacy and safety of transthoracic cannulation to the ascending aorta through a right pleural cavity during minimally invasive cardiac surgery (MICS).

Methods

We retrospectively assessed the records of 104 patients who underwent MICS in our institution between December 2011 and December 2018. Procedures included mitral valve repair (88 patients), aortic valve replacement (8 patients), atrial septal defect closure (6 patients), and myxoma resection (2 patients). Aortic valve replacements were performed through the third intercostal space (ICS), whereas the other procedures were mainly performed through the fourth ICS. The femoral group comprised 60 patients in whom an artificial graft was anastomosed to the femoral artery and 4 who underwent cannulation into the femoral artery. The aorta group comprised 40 patients in whom transthoracic cannulation was performed through the second or third ICS, separate from the main skin incision.

Results

No mortality or critical complications were associated with cardiopulmonary bypass. Perfusion pressure measured at outflow of the artificial lung (224 ± 43 vs. 190 ± 42; P < 0.001) and pump pressure measured at the outflow of the pump (293 ± 50 vs. 255 ± 57; P < 0.001) were significantly higher in the femoral group than in the aorta group. The skin incision lengths were similar (56.9 ± 6.9 vs. 55.1 ± 6.0 mm; P = 0.107).

Conclusions

Transthoracic cannulation into the ascending aorta is reliable and can be safely performed. The possible risks associated with peripheral cannulation and retrograde perfusion can be avoided thereafter.

Mid-Term Results of Peripheral Cannulation After Robotic Cardiac Surgery

Introduction

Various surgical procedures for minimally invasive cardiac surgery have been described in recent decades as alternatives to median sternotomy. Cardiopulmonary bypass via femoral arterial and venous cannulation is the foundation of these procedures. In this study, we evaluated the mid-term outcomes of femoral cannulation performed with U-suture technique in patients undergoing robotic heart surgery.

Methods

A total of 216 patients underwent robotic-assisted cardiac surgery between January 2013 and April 2017. Cardiopulmonary bypass was performed via femoral artery, jugular, and femoral vein cannulation, and a Chitwood clamp was used for aortic occlusion. A total of 192 patients attended the outpatient follow-up, and femoral arterial and venous flow pattern was examined using Doppler ultrasound (DUS) in 145 patients.

Results

Hospital mortality occured in 4 of the 216 (1.85%) cases, but there was no late mortality in this patient group. Postoperatively, seroma (n=9, 4.69%) and cannulation site infection (n=3, 1.56%) were managed with outpatient treatment. DUS in 145 patients revealed triphasic flow pattern in the common femoral arteries in all patients except for 2 (1.38%). These patients were determined to have asymptomatic arterial stenosis. Chronic recanalized thrombus in the common femoral vein was also detected in 2 (1.38%) patients.

Conclusion

Femoral artery cannulation with the U-suture technique can be successfully performed in robotic-assisted cardiac surgery, with good mid-term results.

A Phase 1 Study of a Novel Bidirectional Perfusion Cannula in Patients Undergoing Femoral Cannulation for Cardiac Surgery

Supplemental digital content is available in the text.

Objective

Leg ischemia is a serious complication of femoral artery cannulation. The primary aim of this study was to assess the safety and efficacy of a novel bidirectional femoral arterial cannula (Sorin Group USA, a wholly owned subsidiary of LivaNova PLC, Arvada, CO USA) that provides both antegrade and retrograde flow, in patients undergoing peripheral cannulation for cardiopulmonary bypass during cardiac surgery.

Methods

Patients undergoing routine cardiac surgery requiring femoral artery cannulation for cardiopulmonary bypass were identified preoperatively. Informed written consent was obtained in all cases. Bidirectional cannula insertion used either a surgical cut-down and wire through needle approach or a percutaneous technique. Flow in the superficial femoral artery was assessed using Doppler ultrasound after commencement of cardiopulmonary bypass. Lower limb perfusion was assessed using reflectance near-infrared spectroscopy to measure regional oxygen saturations in the cannulated limb during cardiopulmonary bypass.

Results

Fifteen patients (median age = 61.3 years, range = 26–79 years, 10 males, 5 females) underwent femoral arterial cannulation using the novel bidirectional femoral cannula between August 2016 and May 2017. Fourteen cannulae were inserted directly into the femoral artery via a surgical cut-down and wire through needle technique. One bidirectional cannula was inserted using a percutaneous insertion technique. Indications included minimally invasive mitral and aortic valve surgery, thoracic aortic aneurysm repair, and redo cardiac surgery. The median duration of cardiopulmonary bypass was 129 minutes (range = 53–228 minutes). The cannula was inserted and positioned without difficulty in 14 of 15 patients. Incorrect sizing and arterial spasm prevented correct cannula positioning in one patient. Antegrade flow in the superficial femoral artery was observed on Doppler ultrasound in 12 of 12 patients in which this was performed. Continuous stable distal perfusion was demonstrated in the cannulated limb in 14 of 15 patients. No procedural complications occurred in the immediate or convalescent postoperative period.

Conclusions

This study demonstrates that in patients undergoing femoral arterial cannulation for cardiopulmonary bypass during cardiac surgery, the use of a novel bidirectional cannula is safe and easy to insert and provides stable distal perfusion of the cannulated limb. Use of the device should largely obviate the need to insert a separate downstream perfusion cannula or use other techniques to protect against lower limb ischemia. Further research on a larger scale and in different patient populations is now warranted.

Survey of the American Pediatric Surgical Association on cannulation practices in pediatric ECMO

AIMS

Extracorporeal membrane oxygenation (ECMO) is a commonly used modality of life support for children with cardiopulmonary failure. Consensus on pediatric cannulation strategies and management does not currently exist. The goal of this study was to investigate individual surgeon approaches towards ECMO cannulations in children.

METHODS

A 21-question online survey was developed and disseminated to the American Pediatric Surgical Association (APSA) membership. Participant responses were summarized as counts and percentages. Effect of ECMO volume and surgeon experience on responses was assessed.

RESULTS

There were 252 APSA members who participated in this study for a response rate of 21%, with 225 (89.3%) performing ECMO. Sixty respondents (28.3%) reported using neck vessels exclusively for cannulation regardless of age or weight of the patient. After neck decannulation, 13 (6.6%) repaired the carotid artery for all patients, and 21 (10.7%) repaired only for children older than 5years. Of those performing femoral cannulation, 56 (26.4%) would perform at 5years or older and 66 (31.1%) at 12years. The most common challenge for femoral cannulation was the need for distal perfusion (n=119; 59.8%). Assistance from vascular surgery was requested by 32 (16.4%) for distal perfusion catheter placement, and by 79 (40.5%) for decannulation. Regarding femoral cannulation, lack of training was more likely to be a challenge if performing <5 cannulations per year (25.2% vs 12.5%; p=0.03). Surgeons with <10years of experience were more likely to consult vascular surgery compared to those with >10years of experience (18.5% vs 8%; p=0.03).

CONCLUSION

Considerable variation exists in individual surgeon cannulation practices in pediatric ECMO, in particular in the management of school age and adolescent VA ECMO. Mixed approaches across several ECMO management case study questions indicate that further work is needed to evaluate specific risks with cannulations in children.

LEVEL OF EVIDENCE

IV.

Pressure and Flow Characteristics of a Novel Bidirectional Cannula for Cardiopulmonary Bypass

Objective

Femoral arterial cannulation is associated with a significant risk of lower limb ischemia. The aim of the study was to assess the pressure and flow in the femoral artery using a novel bidirectional femoral cannula in a sheep model of peripheral cardiopulmonary bypass.

Methods

Peripheral cardiopulmonary bypass was established using a multistage venous cannula inserted into the internal jugular vein and the bidirectional or a conventional arterial cannula into the femoral artery in seven adult ewes. Systemic and distal perfusion pressures and flow rates were measured during cardiopulmonary bypass with flow rates of 1, 2, 3, and 4 L/min. Lower limb venous oxygen saturation and lactate levels were also measured.

Results

A significantly higher blood flow in the lower limb using the bidirectional cannula was observed and compared with a conventional cannula at all flow rates (mean flow 115 mL/min vs 10 mL/min, P < 0.05). The mean distal perfusion pressure was also significantly higher in the bidirectional cannula group (86 mm Hg vs 45 mm Hg at 4 L/min of flow, P < 0.05). The bidirectional cannula was associated with higher venous oxygen saturations in the lower limb than in the conventional cannula group; however, lower limb lactate production was similar in the two groups.

Conclusions

This in vivo data demonstrates superior distal flow and pressure characteristics of a novel bidirectional cannula compared with a conventional femoral cannula during peripheral cardiopulmonary bypass.

Review of Extracorporeal Membrane Oxygenation and Dialysis-Based Liver Support Devices for the Use of Nephrologists

Acute kidney injury in the intensive care unit (ICU) is a manifestation of an underlying severe illness that commonly involves other organ systems. Pulmonary, cardiac, and hepatic failures are the most prevalent. This article provides a simplified review of the technical aspects of extracorporeal cardiopulmonary and liver support devices used in the adult ICU patient, as well as a summary of the most relevant and up-to-date clinical evidence that supports their use.

High rate of arterial complications in patients supported with extracorporeal life support for drug intoxication-induced refractory cardiogenic shock or cardiac arrest

BACKGROUND

Cardiac failure is still a leading cause of death in drug intoxication. Extracorporeal life support (ECLS) could be used as a rescue therapeutic option in patients developing refractory cardiogenic shock or cardiac arrest. The aim of this report is to present our results of ECLS in the setting of poisoning from cardiotoxic drugs.

METHODS

We included in this analysis consecutive patients who received an ECLS for refractory cardiogenic shock or in-hospital cardiac arrest due to drug intoxication. The primary endpoint of our study was survival to hospital discharge with good neurological recovery after ECLS support.

RESULTS

Between January 2010 and December 2015, we performed 12 ECLS. Mean age was 44.2±17.8 years and there was a predominance of females (66.7%). Drug intoxication was mainly due to beta-blockers and/or calcium channel inhibitors (83.3%) and 5 (41.7%) patients had multiple drugs overdose. Weaning rate and survival to hospital discharge with good neurological recovery were 75% (9 patients). Among patients weaned from ECLS, mean duration of support was 2.4±1.1 days. Three (25%) patients underwent ECLS implantation during cardiopulmonary resuscitation, 2 (66.6%) of them died while on mechanical circulatory support (MCS). Six (50%) patients developed lower limb ischemia. Each patient was managed with ECLS decannulation: 2 (16.7%) patients underwent a concomitant iliofemoral thrombectomy, 3 (25%) needed further fasciotomy and the remaining patient (8.3%) required an amputation.

CONCLUSIONS

Refractory cardiogenic shock due to drug intoxication is still one of the best indications for ECLS owing to the satisfactory survival with good neurological outcome in such a critically ill population. Further data are however necessary in order to best understand the possible relation between drug intoxication and lower limb ischemia, which was quite superior to the reported rates.

Advanced Age as a Predictor of Survival and Weaning in Venoarterial Extracorporeal Oxygenation: A Retrospective Observational Study

Background. In most reports on ECMO treatment, advanced age is classified as a contraindication to VA ECMO. We attempted to investigate whether advanced age would be a main risk factor deciding VA ECMO application and performing VA ECMO support. We determined whether advanced age should be regarded as an absolute or relative contraindication to VA ECMO and could affect weaning and survival rates of VA ECMO patients. Methods. VA ECMO was performed on 135 adult patients with primary cardiogenic shock between January 2010 and December 2014. Successful weaning was defined as weaning from ECMO followed by survival for more than 48 hours. Results. Among the 135 patients, 35 survived and were discharged uneventfully, and the remaining 100 did not survive. There were significant differences in survival between age groups, and older age showed a lower survival rate with statistical significance (P = .01). By multivariate logistic regression analysis, age was not significantly associated with in-hospital mortality (P = .83) and was not significantly associated with VA ECMO weaning (P = .11). Conclusions. Advanced age is an undeniable risk factor for VA ECMO; however, patients of advanced age should not be excluded from the chance of recovery after VA ECMO treatment.

Arterial Injuries from Femoral Artery Cannulation with Port Access Cardiac Surgery

Although minimally invasive (MI) cardiac surgery reduces blood loss, hospital stay, and recovery time, some MI approaches require femoral arterial cannulation, which introduces a heretofore unknown risk of femoral arterial injury. This study was performed to examine the risk of femoral arterial injury after Port Access MI cardiac surgery (PA-MICS) with femoral cannulation. Data were prospectively obtained on 739 consecutive patients who had PA-MICS with femoral cannulation between June 1996 and April 2000, identifying any patient with new (<30 days postoperative) arterial insufficiency from the cannulation site. Patient characteristics (gender, age, height, weight, body surface area, smoking, peripheral vascular disease, diabetes) and operative variables (cannula size, cross-clamp time) were examined with univariate and multivariate analysis to identify risk factors for arterial injury. Injuries were defined and classified by radiologic and intraoperative assessment, and follow-up was obtained by patient examination and from the medical records. Femoral arterial occlusion (FAC) occurred in 0.68% (5/739) of patients (4 women, 1 man; age range 26–74 years). The risk of femoral injury was higher in women: 1.31% vs 0.23% (p=0.07). One patient had intraoperative limb ischemia from iliofemoral dissection and was treated by axillopopliteal bypass. Four patients presented postoperatively with claudication. Three of these had iliofemoral arterial occlusion or localized iliofemoral dissection and were treated with iliofemoral bypass, and 1 patient had localized femoral artery stenosis treated by angioplasty. With a mean follow-up of 17.8 months (range 13–26 months) limb salvage was achieved in all patients. Secondary or tertiary interventions were required in 40% (2/5), both in patients with iliofemoral occlusion, and 1 patient (20% of femoral injuries, 0.135% of overall series) has chronic graft occlusion and long-term claudication. The risk of arterial injury after femoral arterial cannulation and perfusion for Port Access surgery was low (0.68%). This risk is increased in women and is unpredictable. Initial vascular repair has a significant failure rate, and secondary interventions are often necessary. Although the femoral cannulation and perfusion technique is safe overall, the risk must be clearly recognized.

The Utility of Preemptive Distal Perfusion Cannulation During Peripheral Venoarterial Extracorporeal Membrane Oxygenation Support

OBJECTIVES

We compared the ischemia and rescue rates according to the strategy of distal cannulation.

BACKGROUND

Limb ischemia developing during percutaneous venoarterial (VA) extracorporeal membrane oxygenation (ECMO) is a potentially severe complication. Although appropriate use of a distal perfusion cannula can avoid ischemia, evidences about distal cannulation is still lacking.

METHODS

Patients who underwent peripheral VA ECMO between January 2010 and August 2015 were reviewed. We classified patients into 2 groups in terms of insertion timing with respect to the onset of ischemia. The preemptive strategy group underwent early insertion of a distal perfusion cannula at commencement of ECMO support. The rescue strategy group underwent delayed cannula insertion after onset of limb ischemia.

RESULTS

A total of 151 patients were included in the analysis. Forty-four patients formed the preemptive strategy group and 107 patients formed the rescue strategy group. In total, 10 of 151 (6.7%) patients developed significant limb ischemia, they all were the rescue strategy group (10/107, 9.3%). Of the 10 patients, 2 patients were rescued from limb ischemia after distal cannulation. Otherwise, ischemia was not rescued in the remaining eight patients. Of the latter 8, 3 patient required surgical interventions (2 fasciotomy and 1 below-the-knee amputation) and the other five died from disease aggravation prior to surgical intervention.

CONCLUSIONS

Preemptive distal perfusion cannulation is safe and effective when used to prevent lower limb ischemia in patients undergoing femoral cannulation to treat ECMO. However, delayed distal cannulation increases the extent of cannulation site bleeding, without improving the ischemia.

Numerical simulation of blood flow in femoral perfusion: comparison between side-armed femoral artery perfusion and direct femoral artery perfusion

Computational numerical analysis was performed to elucidate the flow dynamics of femoral artery perfusion. Numerical simulation of blood flow was performed from the right femoral artery in an aortic model. An incompressible Navier-Stokes equation and continuity equation were solved using computed flow dynamics software. Three different perfusion models were analyzed: a 4.0-mm cannula (outer diameter 15 French size), a 5.2-mm cannula (18 French size) and an 8-mm prosthetic graft. The cannula was inserted parallel to the femoral artery, while the graft was anastomosed perpendicular to the femoral artery. Shear stress was highest with the 4-mm cannula (172 Pa) followed by the graft (127 Pa) and the 5.2-mm cannula (99 Pa). The cannula exit velocity was high, even when the 5.2-mm cannula was used. Although side-armed perfusion with an 8-mm graft generated a high shear stress area near the point of anastomosis, flow velocity at the external iliac artery was decreased. The jet speed decreased due to the Coanda effect caused by the recirculation behind sudden expansion of diameter, and the flow velocity maintains a constant speed after the reattachment length of the flow. This study showed that iliac artery shear stress was lower with the 5.2-mm cannula than with the 4-mm cannula when used for femoral perfusion. Side-armed graft perfusion generates a high shear stress area around the anastomotic site, but flow velocity in the iliac artery is slower in the graft model than in the 5.2-mm cannula model.

Does a distal perfusion cannula reduce ischaemic complications of extracorporeal membrane oxygenation?

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) provides support to patients with severe but reversible cardiac or pulmonary failure. Vascular complications of ECMO are well recognized.

METHODS

We performed a retrospective review of 70 patients (mean age 48 years; 15-85) who received peripheral veno-arterial ECMO from 2004 to 2010 in a single centre. For statistical analysis, chi-squared test and multivariate binary logistic regression analysis were used to assess for association between response variables (i.e. limb ischaemia, ECMO site bleeding and deep vein thrombosis (DVT)) and possible predictive variables.

RESULTS

There were 14 (20%) cases of acute limb ischaemia with no statistically significant relationship between acute limb ischaemia and independent variables. Thirty-three patients received distal limb cannulas (47%). There was no statistically significant association between limb ischaemia and presence of distal limb cannula (P = 0.8). Multivariate binary logistic regression analysis identified insertion by cutdown as a predictor of lower probability of insertion site bleeding (n = 12, odds ratio 0.24, P = 0.04). Seven cases of DVT were identified; multivariate binary logistic regression analysis identified insertion by cutdown (odds ratio 0.08, P = 0.03) and days of ECMO less than five (odds ratio 0.08, P = 0.04) as predictive factors for reduced rates of DVT.

CONCLUSION

Ischaemic complications of ECMO are common and occur despite the presence of a distal limb-perfusing cannula; however in our study the distal limb cannula was a limb-salvaging intervention in six patients. Prolonged time on ECMO is a risk factor for DVT, and a high index of suspicion must be maintained. Percutaneous insertion was associated with higher rates of bleeding and DVT.

The State of the Art in Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation has evolved in design, technology, patient selection, insertion techniques, adjunct devices, and management in the past 45 years since it began. Outcomes have improved and indications have expanded. It continues to be an expeditious, cost-effective tool for rapid resuscitation of patients with cardiorespiratory failure, whose outcomes without extracorporeal membrane oxygenation intervention are predominately fatal. However, results are still moderately satisfactory, and the ethical aspects of ongoing care need to be at the forefront of daily family discussions in patients for whom a bridge to transplant or definitive device is not possible.

Management of iatrogenic RV injury - RV packing and CPB through PTFE graft attached to femoral artery

Cardiac injuries during repeat sternotomy are rare. While undergoing debridement for chronic osteomyelitis (post arterial septal defect closure), a 4-year-old girl sustained significant right ventricular (RV) injury. Bleeding from the RV was controlled by packing the injury site, which helped in maintaining stable hemodynamics till arrangements were made for instituting cardiopulmonary bypass (CPB). Since the femoral artery was very small and unsuitable for direct cannulation, a polytetrafluoroethylene (PTFE) graft sutured end-to-side to the femoral artery was used for establishing CPB. The injury was successfully repaired.

Preoperative Vascular Imaging for Predicting Intraoperative Modification of Peripheral Arterial Cannulation during Minimally Invasive Mitral Valve Surgery

Objective

Minimally invasive mitral valve surgery using peripheral cannulation for cardiopulmonary bypass (CBP) is increasingly prevalent. Although conceptually straightforward, peripheral CBP involves challenges and risks specific to this method of perfusion. The utility of preoperative vascular imaging in predicting these technical challenges and preventing vascular complications was studied.

Methods

We performed a retrospective analysis of 73 consecutive patients undergoing minimally invasive mitral valve surgery using femorofemoral CBP with intraluminal aortic occlusion balloon catheter. All patients underwent preoperative computed tomography angiogram or magnetic resonance angiography to study the iliofemoral axes.

Results

None of the patients operated with this technique was found to have arterial stenoses. Patients with a femoral artery diameter of less than 7.3 mm needed bilateral or side-graft arterial cannulation significantly more frequently than patients with larger femoral arteries (46.2% vs 9.1%, P = 0.001). There was a trend toward more frequent modification of arterial cannulation strategy in patients with body surface area less than 1.7 m2 compared with larger patients (body surface area, 1.7–2.0) (26.3% vs 8.3%, P = 0.07). Patients needing high CBP flow rate (>5 L/min) were no more likely to need dual arterial cannulation (18.2% vs 19.1%, P = 0.68). No patient experienced a vascular complication.

Conclusions

This preliminary study suggests that preoperative vascular imaging and patient evaluation may predict difficulties with femoral cannulation and perfusion, which can lead to better preoperative planning and potentially prevent vascular complications. Further data will be accumulated and analyzed to confirm these findings.

Arterial vascular complications in peripheral extracorporeal membrane oxygenation support: a review of techniques and outcomes

Peripheral venoarterial extracorporeal membrane oxygenation support provides prolonged support in the event of acute or acute-on-chronic cardiac and/or respiratory failure. This support serves as a bridge to recovery, decision-making, heart transplantation or ventricular-assist device implantation. It can be implanted either through a percutaneous approach using Seldinger's technique or via an open approach via the common femoral artery or the axillary artery. Early and late arterial vascular complications remain an important issue, with rates of up to 28% with femoral and axillary cannulation sites. Among them, limb ischemia requires prompt diagnosis and management to avoid limb amputation. In the case of peripheral artery cannulation, ipsilateral distal limb perfusion to prevent acute limb ischemia can be performed via a single lumen catheter through the artery or via the 'chimney graft' technique during extracorporeal membrane oxygenation implantation.

Minimally invasive approaches versus conventional sternotomy for aortic valve replacement: a propensity score matching study

Background

The aim of this study is to evaluate our institutional results of the aortic valve replacement through minimally invasive approaches compared with conventional sternotomy.

Materials and Methods

From August 1997 to July 2010, 838 patients underwent primary isolated aortic valve replacement. Of them, 73 patients underwent surgery through minimally invasive approaches (MIAS group) whereas 765 patients underwent surgery through the conventional sternotomy (CONV group). Clinical outcomes were compared using a propensity score matching design.

Results

Propensity score matching yielded 73 pairs of patients in which there were no significant differences in baseline profiles between the two groups. Patients in the MIAS group had longer aortic cross clamp than those in the CONV group (74.9±27.9 vs.. 66.2±27.3, p=0.058). In the MIAS group, conversion to full sternotomy was needed in 2 patients (2.7%). There were no significant differences in the rates of low cardiac output syndrome (4 vs. 8, p=0.37), reoperation due to bleeding (7 vs. 6, p=0.77), wound infection (2 vs. 4, p=0.68), or requirements for dialysis (2 vs. 1, p=0.55) between the two groups. Postoperative pain was significantly less in the MIAS group than the conventional group (pain score, 3.79±1.67 vs. 4.32±1.56; p=0.04).

Conclusion

Both minimally invasive approaches and conventional sternotomy had comparable early clinical outcomes in patients undergoing primary isolated aortic valve replacement. Minimally invasive approaches significantly decrease postoperative pain.

Vascular complications in patients undergoing femoral cannulation for extracorporeal membrane oxygenation support

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a well-established treatment for severe cardiopulmonary failure. Patients undergoing ECMO support through femoral vessels are prone to vascular complications. The aim of this study was to evaluate such complications to outline basic technical principles for their prevention.

METHODS

From January 2005 to December 2009, 174 patients underwent ECMO support through cannulation of the femoral vessels. The primary outcome was any vascular complication. Secondary outcomes were 30-day mortality and 1-year survival. A logistic regression analysis including ECMO duration, peripheral arterial disease, ECMO access (percutaneous versus open), and diabetes mellitus identified predictors for vascular complications.

RESULTS

The venoarterial mode was used in 143 patients (82%), and venovenous in 31 patients (18%). Of the 17 (10%) observed vascular complications, 15 (88%) occurred in patients with venoarterial access, whereas 2 (12%) occurred after venovenous access (p=0.50) Two patients who had extremity ischemia required limb amputation. Thirty-day mortality and 1-year survival rates were 63% and 26%, respectively. Peripheral arterial disease was the only strong predictor of vascular complications (odds ratio, 6.95; 95% confidence interval, 1.89 to 25.59; p=0.003). Vascular complications were not associated with early or late mortality.

CONCLUSIONS

The incidence of vascular complications in venovenous cannulation was low, whereas in arterial cannulation, it is still considerable. Peripheral arterial disease remains a risk factor, and early involvement of vascular surgeons for open vascular exposure or alternative vascular access sites can be recommended. Vascular complications after ECMO support are not associated with higher mortality rates.

New prototype of femoral arterial SmartCannula with anterograde and retrograde flow

OBJECTIVES

Femoral artery cannulation is routinely used in circulatory support scenarios for cardiorespiratory support in patients with acute cardiac and/or pulmonary decompensation. During prolonged perfusion, this may cause acute ischemia of the leg and, in the worst case, even amputation. The aim of this experimental study was to test a newly designed arterial cannula allowing proximal and distal blood flow.

METHODS

Veno-arterial cardiopulmonary bypass was established in three calves (67.6 ± 5.1 kg). The venous line was secured by cannulation of the external jugular vein. The arterial line of each animal was secured by cannulation of iliac arteries on both legs. On one side, we used a modified SmartCannula (SmartCannula 18Fr 130 mm) and, on the other side, a standard rectilinear BioMedicus cannula system was used, 19 Fr for retrograde and an 8 Fr BioMedicus shunt for anterograde flow toward the leg. An ultrasonic flow probe was used to quantify the perfusion of the distal leg.

RESULTS

At 0.5, 1.0, 1.5, and 2.0 l/min, the anterograde leg blood flow increased steadily for each cannula, but remained higher in the self-expanding cannula. That is, the 8 F rectilinear cannula achieved a blood flow of 0.02 ± 0.01, 0.1 ± 0.04, 0.22 ± 0.09, and 0.21 ± 0.02 l/min, respectively, and the 18 F self-expanding cannula achieved 0.06 ± 0.02, 0.15 ± 0.03, 0.24 ± 0.07 and 0.36 ± 0.04 l/min.

CONCLUSION

The modified self-expanding cannula exhibited superior distal arterial flow compared to the routinely used rectilinear shunt system. This has a potential to reduce ischemic events of the inferior extremity in prolonged perfusion.

Percutaneous distal perfusion of the lower extremity after femoral cannulation for venoarterial extracorporeal membrane oxygenation in a small child

Femoral cannulation in pediatric patients requiring extracorporeal membrane oxygenation (ECMO) is commonly associated with distal limb ischemia. Authors have previously reported successful lower limb perfusion using various open techniques to cannulate a distal lower extremity artery at the time of initial ECMO cannulation. These procedures include open femoral artery antegrade cannulation and distal posterior tibial artery retrograde cannulation in older children and adults. Such approaches require ample vessel diameters to accommodate an arteriotomy and catheter insertion and, therefore, are of limited use in smaller children. We hypothesized that after femoral artery cannulation for ECMO, a percutaneous technique of distal limb perfusion might offer unique advantages when treating lower extremity ischemia in small pediatric patients. We report a technique for percutaneous antegrade cannulation in a 4-year-old patient shortly after her primary cannulation for venoarterial ECMO via the femoral artery.

Venous leg congestion treated with distal venous drainage during peripheral extracorporeal membrane oxygenation

Distal venous drainage during extracorporeal membrane oxygenation (ECMO) via femoral cannulation is described. It was performed to relieve distal venous congestion due to obstruction by the venous cannula. Venous drainage was performed with an 11 Fr introducer catheter connected as a T to the main venous line. Its effectiveness was confirmed by clinical examination and Doppler ultrasound in a patient presenting with acute myocarditis. In addition to distal limb perfusion during ECMO, this technique appears safe and simple for adequate distal limb drainage, and can be useful in cases where a change of cannulas is not possible.

A simple technique of distal limb perfusion during prolonged femoro-femoral cannulation

OBJECTIVE

Cannulation of the femoral vessels for cardiopulmonary support is a common approach for many cardiac procedures as well as access of choice for many emergency bypass systems such as extracorporeal membrane oxygenation. A serious complication of prolonged femoral cannulation remains the ischemic injury of the distal limb.

SUBJECTS

To minimize the incidence of ischemia in the cannulated leg, we have begun to provide antegrade femoral blood flow by placing a vascular introducer percutaneously distal to the arterial cannula into the superficial femoral artery and connecting it to the side port of the arterial line.

CONCLUSION

This technique of distal limb perfusion was found to be safe and effective in preventing lower limb ischemia for patients with prolonged femoral cannulation for extracorporeal circulatory support.

A Novel Femoral Arterial Cannula to Prevent Limb Ischemia During Cardiopulmonary Support: Preliminary Report of Experimental and Clinical Experiences

Distal limb ischemia may occur as a serious complication related to the use of femoral cannulation during veno-arterial cardiopulmonary support (CPS). We developed a simple cannula for femoral arterial cannulation with two holes in the side wall, which could provide the distal limb blood flow without additional cannulation or surgical procedure. This cannula can be inserted into the femoral artery by routine Seldinger technique. The distal blood flow from the side holes can be confirmed by Doppler detector without specialized techniques. In porcine experimental model, the distance between the position where the blood flow was first detected and those where the blood leakage took place was at least more than 10 mm. When this cannula and its side holes were adequately positioned, the mean distal limb flow ranged from 75 to 90 mL/min under CPS at a flow of 1.5 L/min. We employed this cannula for six patients in clinical settings. Three patients showed a good distal limb blood flow at the introduction position without its adjustment. The other three patients showed distal limb ischemia at the introduction position, but the limb ischemia was soon recovered after a slight adjustment of its position. There was no blood leakage from the percutaneous entry into the artery in all cases. We currently use this cannula as the first choice for patients undergoing a prolonged CPS.

A femoral artery cannula that allows distal blood flow

OBJECTIVE

A femoral artery cannula is used for certain types of circulatory support but can cause ischemia, especially during prolonged perfusion. This study tests the function of a femoral cannula designed to allow proximal and distal blood flow.

METHODS

Five pigs were used in the study. In each animal a distal-flow cannula was implanted in the femoral artery of one leg, and the same-sized standard cannula was implanted in the other. Blood was drained from the left atrium and delivered to the femoral artery through the distal-flow cannula or standard cannula by using a centrifugal pump. An ultrasonic flow probe and microspheres were used to quantify flow and perfusion distal to the cannula.

RESULTS

Distal femoral flow and tissue perfusion were present in all animals (5/5) with the distal-flow cannula but only in 1 of 5 animals with the standard cannula (P < .048). Distal flow did not change with pump flow. Mean distal flow at each level of pump flow was higher with the distal-flow cannula (P < .05). Tissue perfusion was also higher with the distal-flow cannula (0.052 +/- 0.028 vs 0.010 +/- 0.022 mL x min(-1) x g(-1), P < .03).

CONCLUSIONS

In the swine model the distal-flow cannula allowed greater and more consistent distal flow than the standard cannula. The use of a distal-flow cannula for circulatory support might reduce the risk of distal limb ischemia.

Minimally invasive aortic valve surgery in the elderly: a case-control study

INTRODUCTION

Although minimally invasive aortic valve surgery (MIAVR) is performed in many centers, few studies have compared its results to a standard sternotomy (SS) approach. We assessed the hypothesis that, when compared with SS in the elderly population, MIAVR has similar morbidity and mortality and allows faster hospital recovery.

METHODS AND RESULTS

From January 1995 through February 2002, 515 patients over age 65 underwent isolated aortic valve replacement. Using data gathered prospectively, 189 MIAVR patients were matched with 189 SS patients by age, ventricular function, valvular pathology, urgency of operation, diabetes, previous cardiac surgery, renal disease, and history of stroke. In each group, 56.1% of patients underwent non-elective procedures, and 28% were >or=80 years old. Hospital mortality (6.9%) and freedom from postoperative morbidity (82.5% versus 81.5%, P=0.79) were similar. Multivariate analysis revealed that urgent procedures [Odds Ratio (OR)=3.97; P=0.03], congestive heart failure (OR=3.94; P=0.03), and ejection fraction <30% (OR=4.16; P=0.03) were significant predictors of hospital mortality. Prolonged length of stay was associated with age (P=0.05), preoperative stroke (OR=3.5,P=0.001), CHF (OR=2.2, P=0.004), and sternotomy approach (OR=2.3,P=0.002) by multivariate analysis. More MIAVR patients were discharged home (52.6% versus 38.6%,P=0.03) rather than to rehabilitation facilities. Three year actuarial survival revealed no difference between groups.

CONCLUSIONS

Minimally invasive aortic valve surgery is safe in elderly patients, with morbidity and mortality comparable to sternotomy approach. The shorter hospital stay and greater percentage of patients discharged home after MIAVR reflect enhanced recovery with this technique.

Technique to prevent limb ischemia during peripheral cannulation for extracorporeal membrane oxygenation

Prolonged extracorporeal support using femoral cannulation may cause limb ischemia. A technique is described using antegrade, retrograde arterial perfusion and venous drainage to prevent limb ischemia.

Direct aortic cannulation for port-access mitral or coronary artery bypass grafting

A technique is described for direct aortic arterial cannulation during Port-Access mitral valve or coronary artery bypass grafting. Femoral arterial cannulation is avoided, and endoaortic balloon occlusion is used for cardioplegic arrest. To date, excellent results have been obtained in 45 patients.

Comparison of direct aortic and femoral cannulation for port-access cardiac operations

BACKGROUND

Differences in outcome after direct aortic cannulation (AORT) in the chest versus standard femoral arterial cannulation (FEM) have not been defined for minimally invasive cardiac operations utilizing the port-access approach.

METHODS

A retrospective study was performed of 165 patients undergoing port-access cardiac mitral valve operation (n = 126) or coronary artery bypass grafting (n = 39). In 113 patients, FEM was used, while in 52 patients, AORT was accomplished through a port in the first intercostal space.

RESULTS

AORT eliminated endoaortic balloon clamp migration (0/36 [0%] vs. 17/95 [18%]), and groin wound or femoral arterial complications (0/52 [0%] vs. 11/113 [10%]) without changing procedure times (363+/-55 vs. 355+/-70 minutes). Complications attributable to AORT were injury to the right internal mammary artery and aortic cannulation site bleeding in 1 patient each.

CONCLUSIONS

Direct aortic cannulation is technically easy, allows use of an endoaortic clamp, and avoids aorto-iliac arterial disease, the groin incision, and possible femoral arterial injury associated with femoral arterial cannulation. Direct arterial cannulation should expand the pool of patients eligible for port-access operation, and may become the standard for port-access procedures.