Examination of hemodynamics in patients in hemorrhagic shock undergoing Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA)

Investigating the variability in pressure-volume relationships during hemorrhage and aortic occlusion

Introduction

The pressure-volume (P-V) relationships of the left ventricle are the classical benchmark for studying cardiac mechanics and pumping function. Perturbations in the P-V relationship (or P-V loop) can be informative and guide the management of heart failure, hypovolemia, and aortic occlusion. Traditionally, P-V loop analyses have been limited to a single-beat P-V loop or an average of consecutive P-V loops (e.g., 10 cardiac cycles). While there are several algorithms to obtain single-beat estimations of the end-systolic and end-diastolic pressure-volume relations (i.e., ESPVR and EDPVR, respectively), there remains a need to better evaluate the variations in P-V relationships longitudinally over time. This is particularly important when studying acute and transient hemodynamic and cardiac events, such as active hemorrhage or aortic occlusion. In this study, we aim to investigate the variability in P-V relationships during hemorrhagic shock and aortic occlusion, by leveraging on a previously published porcine hemorrhage model.

Methods

Briefly, swine were instrumented with a P-V catheter in the left ventricle of the heart and underwent a 25% total blood volume hemorrhage over 30 min, followed by either Zone 1 complete aortic occlusion (i.e., REBOA), Zone 1 endovascular variable aortic control (EVAC), or no occlusion as a control, for 45 min. Preload-independent metrics of cardiac performance were obtained at predetermined time points by performing inferior vena cava occlusion during a ventilatory pause. Continuous P-V loop data and other hemodynamic flow and pressure measurements were collected in real-time using a multi-channel data acquisition system.

Results

We developed a custom algorithm to quantify the time-dependent variance in both load-dependent and independent cardiac parameters from each P-V loop. As expected, all pigs displayed a significant decrease in the end-systolic pressures and volumes (i.e., ESP, ESV) after hemorrhage. The variability in response to hemorrhage was consistent across all three groups. However, upon introduction of REBOA, we observed significantly high levels of variability in both load-dependent and independent cardiac metrics such as ESP, ESV, and the slope of ESPVR (Ees). For instance, pigs receiving REBOA experienced a 342% increase in ESP from hemorrhage, while pigs receiving EVAC experienced only a 188% increase. The level of variability within the EVAC group was consistently less than that of the REBOA group, which suggests that the EVAC group may be more supportive of maintaining healthier cardiac performance than complete occlusion with REBOA.

Discussion

In conclusion, we successfully developed a novel algorithm to reliably quantify the single-beat and longitudinal P-V relations during hemorrhage and aortic occlusion. As expected, hemorrhage resulted in smaller P-V loops, reflective of decreased preload and afterload conditions; however, the cardiac output and heart rate were preserved. The use of REBOA and EVAC for 44 min resulted in the restoration of baseline afterload and preload conditions, but often REBOA exceeded baseline pressure conditions to an alarming level. The level of variability in response to REBOA was significant and could be potentially associated to cardiac injury. By quantifying each P-V loop, we were able to capture the variability in all P-V loops, including those that were irregular in shape and believe that this can help us identify critical time points associated with declining cardiac performance during hemorrhage and REBOA use.

Management of Hemorrhagic Shock: Physiology Approach, Timing and Strategies

Hemorrhagic shock (HS) management is based on a timely, rapid, definitive source control of bleeding/s and on blood loss replacement. Stopping the hemorrhage from progressing from any named and visible vessel is the main stem fundamental praxis of efficacy and effectiveness and an essential, obligatory, life-saving step. Blood loss replacement serves the purpose of preventing ischemia/reperfusion toxemia and optimizing tissue oxygenation and microcirculation dynamics. The "physiological classification of HS" dictates the timely management and suits the 'titrated hypotensive resuscitation' tactics and the 'damage control surgery' strategy. In any hypotensive but not yet critical shock, the body's response to a fluid load test determines the cut-off point between compensation and progression between the time for adopting conservative treatment and preparing for surgery or rushing to the theater for rapid bleeding source control. Up to 20% of the total blood volume is given to refill the unstressed venous return volume. In any critical level of shock where, ab initio, the patient manifests signs indicating critical physiology and impending cardiac arrest or cardiovascular accident, the balance between the life-saving reflexes stretched to the maximum and the insufficient distal perfusion (blood, oxygen, and substrates) remains in a liable and delicate equilibrium, susceptible to any minimal change or interfering variable. In a cardiac arrest by exsanguination, the core of the physiological issue remains the rapid restoration of a sufficient venous return, allowing the heart to pump it back into systemic circulation either by open massage via sternotomy or anterolateral thoracotomy or spontaneously after aorta clamping in the chest or in the abdomen at the epigastrium under extracorporeal resuscitation and induced hypothermia. This is the only way to prevent ischemic damage to the brain and the heart. This is accomplishable rapidly and efficiently only by a direct approach, which is a crush laparotomy if the bleeding is coming from an abdominal +/- lower limb site or rapid sternotomy/anterolateral thoracotomy if the bleeding is coming from a chest +/- upper limbs site. Without first stopping the bleeding and refilling the heart, any further exercise is doomed to failure. Direct source control via laparotomy/thoracotomy, with the concomitant or soon following venous refilling, are the two essential, initial life-saving steps.

Intermittent thoracic resuscitative endovascular balloon occlusion of the aorta improves renal function compared to 60 min continuous application after porcine class III hemorrhage

Background

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) may be considered for stabilization of patients with hemorrhage from below the diaphragm. Occluding the aorta is a powerful means of hemorrhagic control but is also associated with acute kidney injury, which increases mortality in trauma patients. Allowing for intermittent distal blood flow during REBOA application (iREBOA) could decrease this risk, but circulatory consequences have not been sufficiently elucidated. Therefore, we investigated circulatory effects and the renal artery blood flow (RBF) in iREBOA versus continuous, complete aortic occlusion (cREBOA).

Methods

In a porcine model of uncontrolled class III hemorrhage (34% estimated total blood volume, mean 1360 mL), swine (n = 12, mean weight 60.3 kg) were randomly assigned to iREBOA: 3-min full deflation every 10 min (n = 6), or cREBOA (n = 6), for 60 min of thoracic (zone I) application. The animals then underwent 60 min of reperfusion (critical care phase).

Results

Survival was 100% in iREBOA and 83% in cREBOA. The intermittent balloon deflation protocol was hemodynamically tolerable in 63% of reperfusion intervals. Systolic blood pressure decreased during the reperfusion intervals in iREBOA animals (mean 108 mm Hg versus 169 mm Hg; p < 0.005). No differences were detected in heart rate, cardiac output or stroke volume between methods. Troponin I increased in cREBOA after 60 min (mean 666–187 ng/L, p < 0.05). The norepinephrine requirement increased in cREBOA during reperfusion (mean infusion time 12.5–5.5 min; p < 0.05). Total ischemic time decreased in iREBOA (60.0–48.6 min; p < 0.001). RBF increased in iREBOA during balloon deflations and after 60 min reperfusion (61%–39% of baseline RBF; p < 0.05). Urine output increased in iREBOA (mean 135–17 mL; p < 0.001). Nephronal osteopontin, a marker of ischemic injury, increased in cREBOA (p < 0.05).

Conclusion

iREBOA was survivable, did not cause rebleeding, decreased the total ischemic time and increased the renal blood flow, urine output and decreased renal ischemic injury compared to cREBOA. Intermittent reperfusions during REBOA may be preferred to be continuous, complete occlusion in prolonged application to improve renal function.

Resuscitative endovascular balloon occlusion of the aorta in civilian pre-hospital care: a systematic review of the literature

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a damage control tool with a potential role in the hemodynamic resuscitation of severely ill patients in the civilian pre-hospital setting. REBOA ensures blood flow to vital organs by early proximal control of the source of bleeding. However, there is no consensus on the use of REBOA in the pre-hospital setting. This article aims to perform a systematic review of the literature about the feasibility, survival, indications, complications, and potential candidates for civilian pre-hospital REBOA.

Methods

A literature search was conducted using Medline, EMBASE, LILACS and Web of Science databases. Primary outcome variables included overall survival and feasibility. Secondary outcome variables included complications and potential candidates for endovascular occlusion.

Results

The search identified 8 articles. Five studies described the use of REBOA in pre-hospital settings, reporting a total of 47 patients in whom the procedure was attempted. Pre-hospital REBOA was feasible in 68–100% of trauma patients and 100% of non-traumatic patients with cardiac arrest. Survival rates and complications varied widely. Pre-hospital REBOA requires a coordinated and integrated emergency health care system with a well-trained and equipped team. The remaining three studies performed a retrospective analysis identifying 784 potential REBOA candidates.

Conclusions

Pre-hospital REBOA could be a feasible intervention for a significant portion of severely ill patients in the civilian setting. However, the evidence is limited. The impact of pre-hospital REBOA should be assessed in future studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40001-022-00836-3.

Inflate and pack! Pelvic packing combined with REBOA deployment prevents hemorrhage related deaths in unstable pelvic fractures

INTRODUCTION

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is advocated for hemorrhage control in pelvic fracture patients in shock. We evaluated REBOA in patients undergoing preperitoneal pelvic packing (PPP) for pelvic fracture-related hemorrhage.

METHODS

Retrospective, single-institution study of unstable pelvic fractures (hemodynamic instability despite 2 units of red blood cells (RBCs) and fracture identified on x-ray). Management included the placement of a Zone III REBOA in the emergency department (ED) for systolic blood pressure <80 mmHg. All PPP patients were included and analyzed for injury characteristics, transfusion requirements, outcomes and complications. Additionally, patients who received REBOA (REBOA+) were compared to those that did not (REBOA-).

RESULTS

During the study period (January 2015 - January 2019), 652 pelvic fracture patients were admitted; 78 consecutive patients underwent PPP. Median RBCs at PPP completion compared to 24 h post-packing were 11 versus 3 units (p<0.05). Median time to operation was 45 min. After PPP, 7 (9%) patients underwent angioembolization. Mortality was 14%. No mortalities were due to ongoing pelvic fracture hemorrhage or physiologic exhaustion; all were a withdrawal of life sustaining support, most commonly due to neurologic insults (TBI/fat emboli = 6, stroke/spinal cord injury = 3). REBOA+ patients (n = 31) had a significantly higher injury severity score (45 vs 38, p<0.01) and higher heart rate (130 vs 118 beats per minute, p = 0.04) than REBOA-. The systolic blood pressure, base deficit, and number of RBCs transfused in the ED, and time spent in the ED were similar between groups. REBOA+ had a higher median transfusion of RBCs at PPP completion (11 units vs 5 units, p<0.01) but similar RBC transfusion in the 24 h after PPP (2 vs 1 units, p = 0.27). Mortality, pelvic infection, and ICU length of stay was not different between these cohorts.

CONCLUSION

PPP with REBOA was utilized in more severely injured patients with greater physiologic derangements. Although REBOA patients required greater transfusion requirements, there were no deaths due to acute pelvic hemorrhage. This suggests the combination of REBOA with PPP provides life-saving hemorrhage control in otherwise devastating injuries.

Survival benefit for pelvic trauma patients undergoing Resuscitative Endovascular Balloon Occlusion of the Aorta: Results of the AAST Aortic Occlusion for Resuscitation in Trauma Acute Care Surgery (AORTA) Registry

BACKGROUND

Aortic occlusion (AO) to facilitate the acute resuscitation of trauma and acute care surgery patients in shock remains a controversial topic. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) is an increasingly deployed method of AO. We hypothesized that in patients with non-compressible hemorrhage below the aortic bifurcation, the use of REBOA instead of open AO may be associated with a survival benefit.

METHODS

From the AAST Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) registry, we identified 1494 patients requiring AO from 45 Level I and 4 Level II trauma centers. Presentation, intervention, and outcome variables were analyzed to compare REBOA vs open AO in patients with non-compressible hemorrhage below the aortic bifurcation.

RESULTS

From December 2014 to January 2019, 217 patients with Zone 3 REBOA or Open AO who required pelvic packing, pelvic fixation or pelvic angio-embolization were identified. Of these, 109 AO patients had injuries isolated to below the aortic bifurcation (REBOA, 84; open AO, 25). Patients with intra-abdominal or thoracic sources of bleeding, above deployment Zone 3 were excluded. Overall mortality was lower in the REBOA group (35.% vs 80%, p <.001). Excluding patients who arrived with CPR in progress, the REBOA group had lower mortality (33.33% vs. 68.75%, p = 0.012). Of the survivors, systemic complications were not significantly different between groups. In the REBOA group, 16 patients had complications secondary to vascular access. Intensive care lengths of stay and ventilator days were both significantly shorter in REBOA patients who survived to discharge.

CONCLUSIONS

This study compared outcomes for patients with hemorrhage below the aortic bifurcation treated with REBOA to those treated with open AO. Survival was significantly higher in REBOA patients compared to open AO patients, while complications in survivors were not different. Given the higher survival in REBOA patients, we conclude that REBOA should be used for patients with hemorrhagic shock secondary to pelvic trauma instead of open AO.

LEVEL III EVIDENCE

Therapeutic.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) may be superior to resuscitative thoracotomy (RT) in patients with traumatic brain injury (TBI)

Background

The effects of aortic occlusion (AO) on brain injury are not well defined. We examined the impact of AO by resuscitative endovascular balloon occlusion of the aorta (REBOA) and resuscitative thoracotomy (RT) on outcomes in the setting of traumatic brain injury (TBI).

Methods

Patients sustaining TBI who underwent RT or REBOA in zone 1 (thoracic aorta) from September 2013 to December 2018 were identified. The indication for REBOA or RT was hemodynamic collapse due to hemorrhage below the diaphragm. Primary outcomes included mortality and systemic complications.

Results

282 patients underwent REBOA or RT. Of these, 76 had mild TBI (40 REBOA, 36 RT) and 206 sustained severe TBI (107 REBOA, 99 RT). Overall, the mean (±SD) age was 42±17 years, with an Injury Severity Score (ISS) of 40±17 and mean systolic blood pressure (SBP) at the time of REBOA or RT of 81±34 mm Hg. REBOA patients had a mean SBP at the time of AO of 78.39±29.45 mm Hg, whereas RT patients had a mean SBP of 83.18±37.87 mm Hg at the time of AO (p=0.24). 55% had ongoing cardiopulmonary resuscitation (CPR) at the time of AO, and the in-hospital mortality was 86%. Binomial logistic regression controlling for TBI severity, age, ISS, SBP at the time of AO, crystalloid infusion, and CPR during AO demonstrated that the odds of mortality are 3.1 times higher for RT compared with REBOA. No significant differences were found in systemic complications between RT and REBOA.

Discussion

Patients with TBI who receive REBOA may have improved survival, but no difference in systemic complications, compared with patients who receive RT for the same indication. Although some patients are receiving RT prior to arrest for extrathoracic hemorrhagic shock, these results suggest that REBOA should be considered as an alternative to RT when RT is chosen for the sole purpose of resuscitation in the setting of TBI.

Level of evidence

4.

Effect of Combined Spinal-Epidural Anesthesia and Total Intravenous Anesthesia on Hemodynamics and Pregnancy Outcomes of Severe Preeclampsia Pregnant Patients Undergoing Cesarean Section

OBJECTIVE

The purpose of the study was to investigate the effect of combined spinal-epidural anesthesia (CSEA) and total intravenous anesthesia (TIVA) on hemodynamics and pregnancy outcomes of severe preeclampsia pregnant patients undergoing cesarean section.

METHODS

126 patients with severe preeclampsia admitted to Zhangqiu District People's Hospital from August 2018 to August 2019 were selected as the study subjects and randomly divided into the experimental group (n = 63) and control group (n = 63). After undergoing cesarean section, the patients in the experimental group received CSEA, while those in the control group were given TIVA. After that, the effect of different anesthesia methods on the hemodynamics and pregnancy outcomes of pregnant women was compared.

RESULTS

There were no significant differences in age, BMI value, weight, height, gestational weeks, SBP, DBP, and residence between the two groups (P > 0.05). The operation duration, the onset time of anesthesia, and delivery time in the experimental group were significantly shorter than those in the control group, with less intraoperative blood loss in the experimental group than that in the control group (P < 0.001). In both groups, MAP and SpO₂ during delivery were significantly lower than those before anesthesia, and HR was significantly higher than that before anesthesia (P < 0.001). In the experimental group, MAP and HR during delivery were significantly lower than those in the control group, and SpO₂ was significantly higher than that in the control group (P < 0.001). The total effective rate of anesthesia in the experimental group was significantly higher than that in the control group (P < 0.05). The Apgar scoring of the newborns in the experimental group was significantly higher than that in the control group (P < 0.001), and the total incidence of postoperative adverse reactions in the experimental group was significantly lower than that in the control group (P < 0.05).

CONCLUSION

CSEA is a reliable anesthesia method for improving the hemodynamics indicators in pregnant patients with severe preeclampsia; such strategy greatly increases the Apgar score of newborns and shortens the anesthesia onset time. Further research will be conducive to establishing a better anesthesia plan for such patients.

Maternal hemodynamics during aortic occlusion with REBOA in patients with placenta accreta spectrum disorder

INTRODUCTION

The effectiveness of resuscitative endovascular balloon occlusion of the aorta (REBOA) in controlling pelvic bleeding has been reported with increasing frequency during surgical management of placenta accreta spectrum (PAS). The deployment of REBOA may lead to significant variations in vital signs requiring special care by anesthesiology during surgery. These modifications of blood pressure by REBOA in PAS patients have not been accurately documented. We report the changes in blood pressure that occur when the aorta is occluded and then released in patients with PAS.

METHODOLOGY

This prospective, observational study includes 10 patients with preoperative PAS suspicion who underwent prophylactic REBOA device insertion between April 2018 and October 2019. REBOA procedural-related data and blood pressure fluctuations under invasive monitoring before and after inflation and deflation were recorded in the operating room.

RESULTS

After prophylactic REBOA deployment in zone 3 of the aorta in PAS patients, we observed a transitory increase in blood pressure (median increase of 22.5 mmHg in SBP and 9.5 mmHg in DBP), which reached severe hypertension (SBP >160 mmHg) in 50% of patients. All patients presented a decrease in blood pressure after the removal of the aortic occlusion (median decrease of 23 mmHg in SBP and 10.5 mmHg in DBP), and 50% (five patients) required the administration of vasopressor drugs.

CONCLUSION

Immediately after aortic occlusion is applied in zone 3 in PAS patients and after the occlusion is removed, significant hemodynamic changes occur, which often lead to therapeutic interventions.

Resuscitative endovascular balloon of the aorta is feasible in penetrating chest trauma with major hemorrhage: Proposal of a new institutional deployment algorithm

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging option for hemorrhage control, but its use is limited in scenarios such as penetrating chest trauma. The aim of this study was to describe the use of REBOA as a resuscitative adjunct in these cases with major hemorrhage and to propose a new clinical management algorithm.

METHODS

This was a prospective, observational study conducted at a single Level I trauma center in Colombia. We included all patients older than 14 years with severe trauma who underwent REBOA from January 2015 to December 2019. Patients received REBOA if they were in hemorrhagic shock and were unresponsive to resuscitation.

RESULTS

A total of 56 patients underwent REBOA placement of which 37 had penetrating trauma and 23 had chest trauma. All patients were hemodynamically unstable upon arrival to the emergency department, with a median systolic blood pressure of 69 mm Hg (interquartile range [IQR], 57-90 mm Hg) and median Injury Severity Score was 25 (IQR, 25-41). All REBOAs were deployed and inflated in zone 1, median inflation time was 40 minutes (IQR, 26-55 minutes), and no adverse neurologic outcomes were observed. Fifteen patients had REBOA and a median sternotomy. Eleven patients had concomitant abdominal wounds. Overall mortality was 28.6%, and there was no significant difference between penetrating versus blunt trauma patients (21.6% vs. 42.1%, p = 0.11). The survival rate of thoracic injured patients was similar to the predicted survival (65.2% vs. 63.3%).

CONCLUSION

Resuscitative endovascular balloon occlusion of the aorta can be used safely in penetrating chest trauma, and the implementation of a REBOA management algorithm is feasible with a well-trained multidisciplinary team.

LEVEL OF EVIDENCE

Therapeutic, level V.

Heparan sulfate chains contribute to the anticoagulant milieu in malignant pleural effusion

Background

While malignant pleural effusion (MPE) is a common and significant cause of morbidity in patients with cancer, current treatment options are limited. Human heparanase, involved in angiogenesis and metastasis, cleaves heparan sulfate (HS) side chains on the cell surface.

Aims

To explore the coagulation milieu in MPE and infectious pleural effusion (IPE) focusing on the involvement of heparanase.

Methods

Samples of 30 patients with MPE and 44 patients with IPE were evaluated in comparison to those of 33 patients with transudate pleural effusions, using heparanase ELISA, heparanase procoagulant activity assay, thrombin and factor Xa chromogenic assays and thromboelastography. A cell proliferation assay was performed. EMT-6 breast cancer cells were injected to the pleural cavity of mice. A peptide inhibiting heparanase activity was administered subcutaneously.

Results

Levels of heparanase, factor Xa and thrombin were significantly higher in exudate than transudate. Thromboelastography detected almost no thrombus formation in the whole blood, mainly on MPE addition. This effect was completely reversed by bacterial heparinase. Direct measurement revealed high levels of HS chains in pleural effusions. Higher proliferation was observed in tumour cell lines incubated with exudate than with transudate and it was reduced when bacterial heparinase was added. The tumour size in the pleural cavity of mice treated with the heparanase inhibitor were significantly smaller compared with control (p=0.005).

Conclusions

HS chains released by heparanase form an anticoagulant milieu in MPE, preventing local thrombosis and enabling tumour cell proliferation. Inhibition of heparanase might provide a therapeutic option for patients with recurrent MPE.