Flying with a Safety Net: Use of REBOA to Enable Safe Transfer to a Level 1 Trauma Center

Background: Using Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) during air and ground transport requires coordination among the responding clinical team, transport team, and receiving surgical team. Here, we describe the development of a REBOA transport program in a civilian medical system that demonstrates the value of REBOA as part of the toolkit for safe casualty transport. Methods: The regional REBOA program was developed at St. Anthony Summit Medical Center in a multi-step planning and training process to ensure coordination among the facilities and transport resources during trauma patient care. Retrospective record review was performed on all patients (n=5) that received REBOA for transport from the Level 3 Trauma Center to the Level 1 Trauma Center, since inception of the program in March 2019. Data were gathered from hospital electronic medical records. Results: SASMC has transported five trauma patients under the REBOA program; all successfully arrived at the Level 1 Trauma Center to receive definitive care. The integrated arterial blood pressure monitoring capability in the REBOA catheter provided robust physiologic data to enable data-driven interventions during transport. Conclusion: The REBOA program described here is a model of how REBOA can be used to enable safe transport between levels of care, when, without REBOA, such transport might not be possible. The model is applicable during care of civilian trauma patients and combat casualties, where injured patients are initially treated in a prehospital or Role1/2 environment but require transport to a Level 1 Trauma Center or Role 3+ for definitive care. Keywords: REBOA, non-compressible hemorrhage, patient transport

Safety profile and risk factors for bleeding in transbronchial cryobiopsy using a two-scope technique for peripheral pulmonary lesions

Background A balloon occlusion technique is suggested for use in cryobiopsy for interstitial lung diseases because of the bleeding risk. However, it may interfere with selection of the involved bronchus for peripheral pulmonary lesions (PPLs). A two-scope technique, in which two scopes are prepared and hemostasis is started using the second scope immediately after cryobiopsy, has also been reported. This study aimed to evaluate the safety and diagnostic utility of transbronchial cryobiopsy using the two-scope technique for PPLs. Methods Data of patients who underwent conventional biopsy followed by cryobiopsy using the two-scope technique for PPLs from November 2019 to March 2021 were collected. The incidence of complications and risk factors for clinically significant bleeding (moderate to life-threatening) were investigated. Diagnostic yields were also compared among conventional biopsy, cryobiopsy, and the combination of them. Results A total of 139 patients were analyzed. Moderate bleeding occurred in 25 (18.0%) patients without severe/life-threatening bleeding. Although five cases required transbronchial instillation of thrombin, all bleeding was completely controlled using the two-scope technique. Other complications included two pneumothoraces and one asthmatic attack. On multivariable analysis, only ground-glass features (P < 0.001, odds ratio: 9.30) were associated with clinically significant bleeding. The diagnostic yields of conventional biopsy and cryobiopsy were 76.3% and 81.3%, respectively (P = 0.28). The total diagnostic yield was 89.9%, significantly higher than conventional biopsy alone (P < 0.001). Conclusions The two-scope technique provides useful hemostasis for safe cryobiopsy for PPLs, with a careful decision needed for ground-glass lesions.

Combined, Converted, and Prophylactic Use of Resuscitative Endovascular Balloon Occlusion of the Aorta for Severe Torso Trauma: A Retrospective Study

Background: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is used as an intra-aortic balloon occlusion method in Japan; however, the protocols for its effective use in different pathological conditions remain unclear. This study aimed to summarise the strategies of REBOA use in severe torso trauma.Methods: Twenty-nine cases of REBOA for torso trauma treated at our hospital over 5 years were divided into the shock (n=12), cardiopulmonary arrest (CPA) (n=13), and non-shock (n=4) groups. We retrospectively examined patient characteristics, trauma mechanism, injury site, severity score, intervention, survival rates at 24 hours, and intervention details in each group.Results: In the shock group, 9 and 3 patients survived and died within 24 hours, respectively; time to intervention (56.6 vs 130.7 min, p=0.346) and total occlusion time (40.2 vs 337.7 min, p=0.009) were both shorter in surviving patients than in the casualties. In the CPA group, 10 patients were converted from resuscitative thoracotomy with aortic cross-clamp (RTACC); a single patient survived. Four patients in the non-shock group survived, having received prophylactic REBOA.Conclusions: The efficacy of REBOA for severe torso trauma depends on patient condition. In the shock group, time to intervention and total occlusion time correlated with survival. The use of REBOA with definitive haemostasis and minimum delays to intervention may improve outcomes. Patients with CPA are at a high risk of mortality; however, conversion from RTACC may be effective in some cases. Prophylactic intervention in the non-shock group may help achieve immediate definitive haemostasis.

In Vitro Model for Simulating Drug Delivery during Balloon-Occluded Transarterial Chemoembolization

Background: Balloon-occluded transarterial chemoembolization (B-TACE) has emerged as a safe and effective procedure for patients with liver cancer, which is one of the deadliest types of cancer worldwide. B-TACE consist of the transcatheter intraarterial infusion of chemotherapeutic agents, followed by embolizing particles, and it is performed with a microballoon catheter that temporarily occludes a hepatic artery. B-TACE relies on the blood flow redistribution promoted by the balloon-occlusion. However, flow redistribution phenomenon is not yet well understood. Methods: This study aims to present a simple in vitro model (IVM) where B-TACE can be simulated. Results: By visually analyzing the results of various clinically-realistic experiments, the IVM allows for the understanding of balloon-occlusion-related hemodynamic changes and the importance of the occlusion site. Conclusion: The IVM can be used as an educational tool to help clinicians better understand B-TACE treatments. This IVM could also serve as a base for a more sophisticated IVM to be used as a research tool.

Angioplasty balloon occlusion of LIMA graft in reoperations of patients with prosthetic valve endocarditis and patent LIMA-LAD graft

Background: Myocardial protection in reoperations in cardiac surgery is extremely difficult in patients with previous coronary surgery and a working LIMA-LAD graft, and it largely determines the outcome of surgery and long-term prognosis. We use a the method of percutaneous angiographic balloon LIMA occlusion and cardioplegic arrest. Aims: The aim of this study was to compare the data of patients with angiographic balloon LIMA-occlusion and those without occlusion in operations related to PVE, and previous coronary surgery with permeable LIMA graft, determining the degree of safety and benefits of method. Study design and Methods: A total of 20 patients undergoing surgery for prosthesis valve endocarditis with patent LIMA-LAD graft were analyzed retrospectively. We divide the patients into 2 groups. Group A patients - with LIMA occlusion and Group B patients - without LIMA occlusion). The pre-, intra- and postoperative results were compared and the degree of safety and benefits of the application of the method were studied. Results: 80% of patients in group A needed only dopamine infusion and 20% needed the addition of a second catecholamine (Adrenaline) at the end of CPB. In group B, the need for double catecholamine maintenance is in 50% of patients. The need for implantation of an intra-aortic balloon pump due to refractory heart failure was registered in 10% of patients in group A and in 20% of patients in group B. It was found that the average duration of mechanical ventilation in group A is 10.5 hours postoperatively, and in group B - 12.5 hours. The mean duration of catecholamine infusion in both groups was 3 days. The average stay in intensive care is shorter for patients in Group A - 2.5 days, and in Group B is 3.5 days. In terms of survival - mortality in the group with LIMA occlusion is 0%, while in the group without LIMA occlusion is 20%. Conclusion: Our reported results from the use of the LIMA balloon occlusion method in patients with prosthetic valve endocarditis who are high-risk and complicated patients and nevertheless the mortality in this group studied by us is 0% and no serious complications of the applied method have been registered. Therefore, we believe that the angiographic balloon LIMA occlusion is a reliable, easily applicable and relatively safe technique that improves the surgical results and prognosis of patients in need of reoperative cardiac surgery.

Changes in peripheral arterial blood pressure after resuscitative endovascular balloon occlusion of the aorta (REBOA) in non-traumatic cardiac arrest patients

Background Resuscitative endovascular balloon occlusion of the aorta (REBOA) may be an adjunct treatment to cardiopulmonary resuscitation (CPR). Aortic occlusion may increase aortic pressure and increase the coronary perfusion pressure and the cerebral blood flow. Peripheral arterial blood pressure is often measured during or after CPR, however, changes in peripheral blood pressure after aortic occlusion is insufficiently described. This study aimed to assess changes in peripheral arterial blood pressure after REBOA in patients with out of hospital cardiac arrest. Methods A prospective observational study performed at the helicopter emergency medical service in Trondheim (Norway). Eligible patients received REBOA as adjunct treatment to advanced cardiac life support. Peripheral invasive arterial blood pressure and end-tidal CO2 (EtCO2) was measured before and after aortic occlusion. Differences in arterial blood pressures and EtCO2 before and after occlusion was analysed with Wilcoxon Signed Rank test. Results Five patients were included to the study. The median REBOA procedural time was 11 min and median time from dispatch to aortic occlusion was 50 min. Two patients achieved return of spontaneous circulation. EtCO2 increased significantly 60 s after occlusion, by a mean of 1.16 kPa (p = 0.043). Before occlusion the arterial pressure in the compression phase were 43.2 (range 12–112) mmHg, the mean pressure 18.6 (range 4–27) mmHg and pressure in the relaxation phase 7.8 (range − 7 – 22) mmHg. After aortic occlusion the corresponding pressures were 114.8 (range 23–241) mmHg, 44.6 (range 15–87) mmHg and 14.8 (range 0–29) mmHg. The arterial pressures were significant different in the compression phase and as mean pressure (p = 0.043 and p = 0.043, respectively) and not significant in the relaxation phase (p = 0.223). Conclusion This study is, to our knowledge, the first to assess the peripheral invasive arterial blood pressure response to aortic occlusion during CPR in the pre-hospital setting. REBOA application during CPR is associated with a significantly increase in peripheral artery pressures. This likely indicates improved central aortic blood pressure and warrants studies with simultaneous peripheral and central blood pressure measurement during aortic occlusion. Trial registration The study is registered in ClinicalTrials.gov (NCT03534011).