Comparing short versus standard-length balloon for intra-aortic counterpulsation: results from a porcine model of myocardial ischaemia-reperfusion

Reduction in Balloon Pump Size Reduces Axillary Intraaortic Balloon Pump Failure Risk

Axillary artery intra-aortic balloon pump (axIABP) placement has been implemented as a bridging solution before heart transplantation. This study evaluates complications associated with axIABP support and describes an approach to minimize adverse events. We previously described a percutaneous approach for axIABP placement. However, patients receiving axIABP between September 1, 2017, and September 26, 2019 (n = 32) demonstrated a high rate of balloon pump malfunction (8/32; 25%) and other complications (totaling 15/32; 47%). Sixty-four patients were sequentially treated under a revised protocol. Compared to the initial cohort, no significant differences in demographics were noted. A significant reduction in rate of balloon malfunction (8/32, 25% vs. 1/64, 2%; p < 0.001) and total complications (15/32, 47% vs. 10/64, 16%; p = 0.0025) during the period of support were noted after intervention. Subsequent analysis of total complications per device size (40 vs. ≤ 34 ml balloon) revealed significantly reduced complications in patients with smaller devices (40% vs. 13%, respectively; p = 0.0022). This study provides guidelines to limit complications in patients supported with axIABP, facilitating a protracted period of bridging support.

Common complications and prevention strategies for resuscitative endovascular balloon occlusion of the aorta: A narrative review

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is considered a key measure of treatment due to its use in stabilizing patients in shock through temporary inflow occlusion for noncompressible torso hemorrhage as well as its supportive role in myocardial and cerebral perfusion. Although its clinical efficacy in trauma has been widely recognized, concerns over related complications, such as vascular access and ischemia-reperfusion, are on the rise. This paper aims to investigate complications associated with REBOA and identify current and emerging prevention or mitigation strategies through a literature review based on human or animal data. Common complications associated with REBOA include ischemia/reperfusion injuries, vessel injuries, venous thromboembolism, and worsening proximal bleeding. REBOA treatment outcomes can be improved substantially with the help of precise selection of patients, better visualization tools, improvement in balloon catheters, blockage strategies, and medication intervention measures. Better understanding of REBOA-related complications and further research on the strategies to mitigate the occurrence of such complications will be of vital importance for the optimization of the clinical outcomes in patients.

Still a place for aortic counterpulsation in cardiac surgery and patients with cardiogenic shock?

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2021. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2021 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from https://link.springer.com/bookseries/8901 .

Aortic flow below and visceral circulation during aortic counterpulsation: Evaluation of an in vitro model

INTRODUCTION

This study aimed to test a computer-driven cardiovascular model for the evaluation of the visceral flow during intra-aortic balloon pump (IABP) assistance.

METHODS

The model includes a systemic and pulmonary circulation as well as a heart contraction model. The straight polyurethane tube aorta had a single visceral while four windkessel components mimicked resistance compliance of the brachiocephalic, renal and sub-mesenteric, pulmonary, and systemic circulation. Twelve flow probes were placed in the circuit to measure pressures and flows with the IABP on and off.

RESULTS

With the balloon off, the meantime to reach the steady state was 48 ± 16 s; with the balloon on, this figure was 178 ± 20 s. The stability of pressure and flow signals was obtained after 72 ± 11 min. The number of cycles of stability of the system was 93 [86-103]. Measurements were reliable either with samples of 10 or 20 beats. Bland Altman method demonstrated the reliability of measurements. Finally, all measurements were comparable to published in vivo data.

CONCLUSION

The presented mock circulation was reliable and gave values with high accuracy both at baseline and during mechanical assistance. This system allows evaluation of the mesenteric flow during IABP, under different clinical/hemodynamic conditions. Nonetheless, its translational potential needs to be further evaluated.

Intra-Aortic Balloon Pump Bridging to Heart Transplantation: Impact of the 2018 Allocation Change

BACKGROUND

This study evaluates the impact of the 2018 allocation policy change on outcomes of orthotopic heart transplantation (OHT) in patients bridged with intra-aortic balloon pumps (IABPs).

METHODS

Adult (≥18 years) patients undergoing OHT between 2013 and 2019 who were bridged with an IABP were stratified based on temporal relation to the policy change. Univariate analysis was used to compare baseline characteristics and postoperative outcomes. Multivariate Cox regression analysis was used to estimate risk-adjusted predictors of post-transplant mortality.

RESULTS

A total of 1342 (8.6%) OHT patients were bridged with an IABP during the study period. Rates of bridging with IABP to OHT increased significantly after the policy change (7.0% versus 24.9%, P<0.001). The mean recipient age was 54.1±12.1 years with 981 (73.1%) patients being male. Baseline characteristics were similar between the 2 groups whereas post-policy change patients spent fewer days on the waitlist (15 versus 35 days, P<0.001), had longer ischemic times (3.5 versus 3.0 hours, P<0.001), and received organs from a greater distance (301 versus 105 miles, P<0.001). By multivariable analysis, days on the waitlist (for every 30 days; odds ratio, 1.01 [95% CI, 1.00-1.02], P=0.031) and diabetes mellitus (odds ratio, 1.87 [95% CI, 1.16-3.02], P=0.011) emerged as significant predictors of post-transplant mortality. After the policy change, waitlisted patients requiring IABP support were more likely to survive to transplant (76.4 versus 89.8%, P<0.001).

CONCLUSIONS

IABP utilization has increased over 3-fold since the 2018 policy change with improved waitlist outcomes and comparable post-OHT survival. Thus, bridging patients to OHT with IABPs appears to be an effective strategy in the current era.

Superior mesenteric flow pattern during counterpulsation: is simply a shorter balloon the solution for visceral hypoperfusion?

OBJECTIVES

We studied the flow pattern in the superior mesenteric artery (SMA) during intra-aortic balloon pump support, comparing 2 intra-aortic balloons of 2 different lengths.

METHODS

Sixteen Landrace pigs (mean weight 84.0 kg ± 6.0) were used in this study. The animals were randomly assigned to 2 groups: group 1 received an 8-Fr, 40-ml standard balloon; group 2 received an 8-Fr, 40-ml short balloon. SMA flow was measured during early, mid- and telediastole.

RESULTS

The standard balloon led to a reduction in SMA flow in early diastole (P < 0.001), a negative flow in mid-diastole (P < 0.001) and a reincrease in telediastole (P < 0.001). In contrast, in early diastole a significant reduction was observed with the short balloon (P < 0.001), followed by another drop in mid-diastole (P < 0.001), without reaching negative values and by a telediastolic increase (P < 0.001). SMA flows were comparable between balloons during early diastole (P = 0.66), whereas they were higher with the short balloon during mid (P < 0.001) and telediastole (P = 0.02). Overall, the diastolic area was significantly larger when the short balloon was used (P < 0.001). Finally, during counterpulsation, mesenteric resistances increased significantly (P < 0.001), although, with the short balloon, they were lower than with the standard balloon (P = 0.01).

CONCLUSIONS

Despite better overall mean mesenteric diastolic flow, the short balloon leads to early- and mid-diastolic flow reduction, although to a lesser extent than the standard intra-aortic balloon pump balloon. Our data are a call for improvement in the design of the short balloon.

Vascular complications following intra-aortic balloon pump implantation: an updated review

Background:

The use of the intra-aortic balloon pump (IABP) as a support device remains controversial due to the fact that a number of studies have shown no benefit in end mortality whilst using this device. One of the reasons for this could be the increase in vascular complications when using the pump. Therefore, the aim of the present review was to assess the current literature available with regards to IABP vascular complications during the clinical situation.

Methods:

A literature search was performed, searching for IABP complications in adult human studies between 1990 and 2016.

Results:

A total of 20 reports were identified as fitting the criteria of this study. The majority of vascular complications were limb ischemia, bleeding or mesenteric ischemia. The overall incidence of vascular complications ranged from 0.94% to 31.1%. Diabetes, peripheral vascular disease and hypertension, as well as smoking were all identified as risk factors for complications following IABP. Furthermore, studies supported the use of sheathless balloon insertion to reduce the risk of complications.

Conclusion:

Major vascular complications, including limb and mesenteric ischemia as well as bleeding and hemorrhage, have been associated with IABP. However, the incidence of these complications was generally low. Further studies are still required to truly understand the risk/benefit associated with the use of IABP.