INTRA-ABDOMINAL PRESSURE MONITORING DURING LÁZARO DA SILVA'S PROCEDURE FOR VENTRAL HERNIA REPAIR: A CROSS-SECTIONAL STUDY.

BACKGROUND: Maintaining normal intra-abdominal pressure (IAP) levels must be one major outcome of any ventral hernia repair, avoiding hypertension or abdominal compartment syndrome. AIMS: To evaluate IAP during ventral hernia repair using Lázaro da Silva's procedure. METHODS: IAP measurements using intravesical pressure were performed during four crucial intraoperative moments. Twenty-eight patients submitted to incisional herniorrhaphy were analyzed. RESULTS: The IAP increased by 0.5 mmHg during the procedure, regardless of the type of prior laparotomy, sex, age, obesity, or hernia width. CONCLUSIONS: Despite the IAP increase observed, Lázaro da Silva's procedure did not result in intra-abdominal hypertension or abdominal compartment syndrome.

[Successful treatment of severe purulent peritonitis against the background of intraperitoneal hypertension syndrome (clinical case)]. / Uspeshnoe lechenie tyazhelogo gnoinogo peritonita na fone sindroma vnutribryushnoi gipertenzii (klinicheskii sluchai).

Traditional surgical treatment of widespread purulent peritonitis has some disadvantages that emphasizes the need for new approaches to postoperative care. The authors present successful treatment of diffuse purulent peritonitis using a combination of 'open abdomen' technology and VAC therapy. This approach reduces abdominal inflammation and intra-abdominal pressure. Combination of 'open abdomen' technology and VAC therapy provides effective control of inflammation and stabilization of patients with purulent peritonitis.

Increasing Use of Prophylactic Open Abdomen Therapy With Vacuum Assisted Wound Closure and Mesh Mediated Fascial Traction After Repair of Ruptured Abdominal Aortic Aneurysm.

OBJECTIVE: Open abdomen therapy (OAT) is commonly used to prevent or treat abdominal compartment syndrome (ACS) in patients with ruptured abdominal aortic aneurysms (rAAAs). This study aimed to evaluate the incidence, treatment, and outcomes of OAT after rAAA from 2006 to 2021. Investigating data on resuscitation fluid, weight gain, and cumulative fluid balance could provide a more systematic approach to determining the timing of safe abdominal closure. METHODS: This was a single centre observational cohort study. The study included all patients treated for rAAA followed by OAT from October 2006 to December 2021. RESULTS: Seventy-two of the 244 patients who underwent surgery for rAAA received OAT. The mean age was 72 ± 7.85 years, and most were male (n = 61, 85%). The most frequent comorbidities were cardiac disease (n = 31, 43%) and hypertension (n = 31, 43%). Fifty-two patients (72%) received prophylactic OAT, and 20 received OAT for ACS (28%). There was a 25% mortality rate in the prophylactic OAT group compared with the 50% mortality in those who received OAT for ACS (p = .042). The 58 (81%) patients who survived until closure had a median of 12 (interquartile range [IQR] 9, 16.5) days of OAT and 5 (IQR 4, 7) dressing changes. There was one case of colocutaneous fistula and two cases of graft infection. All 58 patients underwent successful abdominal closure, with 55 (95%) undergoing delayed primary closure. In hospital survival was 85%. Treatment trends over time showed the increased use of prophylactic OAT (p ≤ .001) and fewer ACS cases (p = .03) assessed by Fisher's exact test. In multivariable regression analysis fluid overload and weight reduction predicted 26% of variability in time to closure. CONCLUSION: Prophylactic OAT after rAAA can be performed safely, with a high rate of delayed primary closure even after long term treatment.

The open abdomen in trauma, acute care, and vascular and endovascular surgery: comprehensive, expert, narrative review.

BACKGROUND: The open abdomen is an innovation that greatly improved surgical understanding of damage control, temporary abdominal closure, staged abdominal reconstruction, viscera and enteric fistula care, and abdominal wall reconstruction. This article provides an evidence-informed, expert, comprehensive narrative review of the open abdomen in trauma, acute care, and vascular and endovascular surgery. METHODS: A group of 12 international trauma, acute care, and vascular and endovascular surgery experts were invited to review current literature and important concepts surrounding the open abdomen. RESULTS: The open abdomen may be classified using validated systems developed by a working group in 2009 and modified by the World Society of the Abdominal Compartment Syndrome-The Abdominal Compartment Society in 2013. It may be indicated in major trauma, intra-abdominal sepsis, vascular surgical emergencies, and severe acute pancreatitis; to facilitate second look laparotomy or avoid or treat abdominal compartment syndrome; and when the abdominal wall cannot be safely closed. Temporary abdominal closure and staged abdominal reconstruction methods include a mesh/sheet, transabdominal wall dynamic fascial traction, negative pressure wound therapy, and hybrid negative pressure wound therapy and dynamic fascial traction. This last method likely has the highest primary fascial closure rates. Direct peritoneal resuscitation is currently an experimental strategy developed to improve primary fascial closure rates and reduce complications in those with an open abdomen. Primary fascial closure rates may be improved by early return to the operating room; limiting use of crystalloid fluids during the surgical interval; and preventing and/or treating intra-abdominal hypertension, enteric fistulae, and intra-abdominal collections after surgery. The majority of failures of primary fascial closure and enteroatmospheric fistula formation may be prevented using effective temporary abdominal closure techniques, providing appropriate resuscitation fluids and nutritional support, and closing the abdomen as early as possible. CONCLUSION: Subsequent stages of the innovation of the open abdomen will likely involve the design and conduct of prospective studies to evaluate appropriate indications for its use and effectiveness and safety of the above components of open abdomen management.

Logistic regression analysis of risk factors for intra-abdominal hypertension after giant ventral hernia repair: a retrospective cohort study.

BACKGROUND: Intra-abdominal hypertension (IAH) is a classical complication after giant ventral hernia surgery and may lead to abdominal compartment syndrome (ACS). Assessment of risk factors and prevention of IAH/ACS are essential for hernia surgeons. METHODS: We performed a retrospective study including 58 giant ventral hernia patients in our center between Jan 1, 2017, and Mar 1, 2022, we recorded age, gender, chronic obstructive pulmonary disease (COPD), coronary heart disease (CHD), hypertension, type 2 diabetes mellitus (T2DM), hypoproteinemia, body mass index (BMI), the ratio of hernia sac volume to abdominal cavity volume (HSV/ACV), defect width, tension reduction procedure (TRP), positive fluid balance (PFB) and IAH of these patients and analyzed the data using univariate and multivariate logistic regression to screen the risk factors for IAH after surgery. RESULTS: The multivariate analysis showed that HSV/ACV ≥ 25%, hypoproteinemia, and PFB were independent risk factors for the occurrence of IAH after giant ventral hernia repair (P = 0.025, 0.016, 0.017, respectively). We did not find any correlation between postoperative IAH and the patient's age, gender, COPD, CHD, hypertension, T2DM, BMI, defect width, TRP, and PFB. CONCLUSION: Identifying risk factors is of great significance for the early identification and prevention of IAH/ACS. We found that HSV/ACV ≥ 25%, hypoproteinemia, and PFB were independent risk factors for IAH after giant ventral hernia repair.

Bedside decompression of abdominal compartment syndrome caused by spontaneous pneumoperitoneum: A case report.

Pneumoperitoneum is the presence of free air within the peritoneal cavity and indicates perforation of a hollow viscus. However, it may also occur in the absence of perforation and in this case, it is called spontaneous pneumoperitoneum (SP). A 57-year-old female patient who was intubated and mechanically ventilated due to respiratory failure developed abdominal compartment syndrome (ACS) secondary to massive SP. Peritoneal lavage was performed for the patient both to achieve decompression and to support the diagnosis. Many surgeons proceed with laparotomy as a reflex response for SP due to lack of awareness of the condition. However, laparotomy has no place in this setting. SP coexisting with ACS is extremely rare. With this case report, we aimed to raise awareness of SP among physicians and help avoid unnecessary laparotomies.

Derivation and Validation of a Risk Score for Abdominal Compartment Syndrome after Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysms.

BACKGROUND: Abdominal compartment syndrome (ACoS) is a devastating complication after endovascular aneurysm repair for ruptured abdominal aortic aneurysms (rEVAR). This study sought to develop a risk score for ACoS to identify patients who would benefit from early decompressive laparotomy. METHODS: Model derivation was performed with Vascular Quality Initiative data for rEVAR from 2013 to 2020. The primary outcome was evacuation of abdominal hematoma. A multivariable logistic regression was used to create and validate a scoring system to predict ACoS. The model was validated using institutional data for rEVAR from 1998 to 2019. RESULTS: The derivation cohort included 2,310 patients with rEVAR. Abdominal hematoma evacuation occurred in 265 patients (11.5%). Factors associated with abdominal hematoma evacuation on a multivariable analysis included transfer from an outside hospital, preoperative creatinine ≥1.4 mg/dL, preoperative systolic blood pressure ≤85 mmHg, preoperative altered mental status, ≥3.0 liters intraoperative crystalloid, and ≥4 units of red blood cells transfused intraoperatively. The validation cohort consisted of 67 rEVAR; ACoS occurred in 8 patients (11.9%). The c-statistic was 0.84 in the derivation and 0.87 in the validation cohort, whereas Hosmer-Lemeshow was P = 0.15 in the derivation and 0.84 in the validation cohorts, suggesting good model discrimination and calibration. Points were applied based on ß-coefficients to produce a risk score ranging from -1 to 13. A cutoff of risk score ≥8 resulted in a sensitivity and specificity of 87.5% and 83.1% for detecting patients with ACoS, respectively. ACoS conveyed a significantly higher mortality in both the derivation (ACoS: 49.8% vs. No ACoS: 17.8%; P < 0.001) and validation cohorts (ACoS: 75.0% vs. No ACoS: 15.2%; P < 0.001). CONCLUSIONS: In patients with equivocal signs/symptoms of ACoS, this scoring system can be used to guide surgeons on when to perform decompressive laparotomy prior to leaving the operating room for rEVAR. Patients with a risk score ≥8 would benefit from decompressive laparotomy at index rEVAR.

Open abdomen during extracorporeal membrane oxygenation is a safe and effective treatment for abdominal compartment syndrome.

BACKGROUND/PURPOSE: Decompressive laparotomy and open abdomen for abdominal compartment syndrome have been historically avoided during Extracorporeal Membrane Oxygenation (ECMO) due to seemingly elevated risks of bleeding and infection. Our goal was to evaluate a cohort of pediatric respiratory ECMO patients who underwent decompressive laparotomy with open abdomen at a single institution and to compare these patients to ECMO patients without open abdomen. METHODS: We reviewed all pediatric respiratory ECMO (30 days-18 years) patients treated with decompressive laparotomy with open abdomen at Riley Hospital for Children (1/2000-12/2019) and compared these patients to concurrent respiratory ECMO patients with closed abdomen. We excluded patients with surgical cardiac disease. We assessed demographics, ECMO data, and outcomes and defined significance as p = 0.05. RESULTS: 6 of 81 ECMO patients were treated with decompressive laparotomy and open abdomen. Open and closed abdomen groups had similar age (p = 0.223) and weight (0.286) at cannulation, but the open abdomen group had a higher reliance on vasoactive medications (Vasoactive Inotropic Score, p = 0.040). Open abdomen group survival was similar to closed abdomen patients (66.7%, vs 62.7%, p = 1). Open abdomen patients had lower incidence of ECMO complications (33.3% vs 83.6%, p = 0.014), but the groups had similar bleeding complications (p = 0.412) and PRBC transfusion volume (p = 0.941). CONCLUSION/IMPACT: Pediatric ECMO patients with open abdomen after decompressive laparotomy had similar survival, blood products administered, and complications as those with a closed abdomen. An open abdomen is not a contra-indication to ECMO support in pediatric respiratory patients and should be considered in select patients.

Feasibility of open abdomen surgery treatment for near fatal necrotizing enterocolitis in preterm infants.

INTRODUCTION: Necrotizing Enterocolitis (NEC) remained a dramatic complication leading to death or neonatal morbidities in preterms. For some, Intra-Abdominal Hypertension (IAH) and Abdominal Compartment Syndrome worsened the multi-organ failure. An open abdomen surgery could be an alternative to conventional surgical treatment to move beyond this stage. OBJECTIVES: To retrospectively describe the clinical course, pre- and post-operative features of preterms suffering from severe NEC with IAH treated by open abdomen surgery and referred to our center from October 2007 to September 2019. Our secondary objective is to identify various risk factors for mortality in this population. METHODS: Data on neonatal, clinical, biological, pre and post-operative features and outcome were collected. Univariate analyses were performed to compare their pre and post-operative features stratifying on outcome. RESULTS: Among 29 included patients, 14 (48%) survived to discharge without short bowel syndrome. Death was associated with an earlier postnatal age at NEC (16.3 ± 9.1 versus 31.3 ± 25.9 days; p = 0.004) and followed a withdrawal of treatment in 60% of cases. Surgery was associated with a significant improvement of respiratory and hemodynamic features (decrease of mean ventilator pressure from 13.1 ± 5.4 to 11.3 ± 4.0 cmH2O, p < 0.001), oxygen requirement (mean FiO2 decreased from 65.0% ± 31.2 to 49.0% ± 24.6, p < 0.001) and inotropic score (from 38.6 ± 70.1 to 29.9 ± 64.3, p < 0.001). In the survival group, pre and post-operative findings exhibited a significant increase of serum lactate concentrations from 2.7 ± 1.6 to 11.0 ± 20.3 mmol/L (p = 0.02) but a similar pH. CONCLUSION: Open abdomen surgery could be considered to rescue preterms with near fatal NEC. IAH and Abdominal Compartment Syndrome in these preterms should be investigated through further studies. LEVEL OF EVIDENCE: Level III.

Abdominal compartment syndrome secondary to chronic constipation in MECP2 duplication syndrome.

Abdominal compartment syndrome (ACS) is an infrequently encountered life-threatening disorder characterised by elevated abdominal pressure with evidence of new organ dysfunction. It is rarely reported in paediatrics. We describe an extremely unusual presentation of a 13-year-old boy with long-standing constipation who developed ACS complicated by refractory septic shock and multiorgan failure. He was treated with emergent decompressive laparotomy and supportive critical care. This case highlights the need for early diagnosis and timely management of ACS to improve its outcome.

Management of abdominal compartment syndrome in acute pancreatitis.

Abdominal compartment syndrome (ACS), defined by the presence of increased intra-abdominal pressure>20mmHg in association with failure of at least one organ system, is a common and feared complication that may occur in the early phase of severe acute pancreatitis (AP). This complication can lead to patient death in the very short term. The goal of this review is to provide the surgeon and intensivist with objective information to help them in their decision-making. In the early phase of severe AP, it is essential to monitor intra-vesical pressure (iVP) to allow early diagnosis of intra-abdominal hypertension or ACS. The treatment of ACS is both medical and surgical requiring close collaboration between the surgical and resuscitation teams. Medical treatment includes vascular volume repletion, prokinetic agents, effective curarization and percutaneous drainage of large-volume ascites. If uncontrolled respiratory or cardiac failure develops or if maximum medical treatment fails, most teams favor performing an emergency xipho-pubic decompression laparotomy with laparostomy. This procedure follows the principles of abbreviated laparotomy as described for abdominal trauma.

A Novel Abdominal Decompression Technique to Treat Compartment Syndrome After Burn Injury.

BACKGROUND: Prevalence of abdominal compartment syndrome (ACS) is estimated to be 4%-17% in severely burned patients. Although decompressive laparotomy can be lifesaving for ACS patients, severe complications are associated with this technique, especially in burn populations. This study outlines a new technique of releasing intraabdominal pressure without resorting to decompressive laparotomy. MATERIALS AND METHODS: Ten fresh tissue cadavers were studied; none of whom had had prior abdominal surgery. Using Veress needles, abdomens were insufflated to 30 mm Hg and subsequently connected to arterial pressure transducers. Two techniques were then used to incise fascia. First, large skin flaps were raised from a midline incision (n = 5). Second, small 2 cm cutdowns at the proximal and distal extent of midaxillary, subcostal, and inguinal incisional sites were made, followed by tunneling a subfascial plane using an aortic clamp with fascial incisions made through the grooves of a tunneled vein stripper (n = 5). Pressures were recorded in the sequence of incisions mentioned previously. RESULTS: The open midline flap technique decreased abdominal pressure from a mean pressure of 30 ± 1.8 mm Hg to 6.9 ± 5.0 mm Hg (P < 0.01). The minimally invasive technique decreased intraabdominal pressure from 30 ± 0.9 to 5.8 ± 5.2 mm Hg (P < 0.01). This technique significantly reduced intraabdominal pressure via extraperitoneal component separation and fascial release at the midaxillary, subxiphoid, and inguinal regions. CONCLUSIONS: This technique offers the benefit of reducing the morbidity, mortality, and complications associated with an open abdomen, which may be beneficial in the burn injury population.

Intraabdominal Lavage of Hypochlorous Acid: A New Paradigm for the Septic and Open Abdomen.

INTRODUCTION: Management of the open abdomen (OA) has rapidly evolved over the last several decades due to the improved understanding of the underlying pathophysiology of patients with an OA, adoption of damage control surgery, and the use of temporary abdominal closure (TAC) techniques for this patient population. The TAC utilizing negative pressure has been successful for managing patients with an OA with improved time to closure. Recent studies have started to examine the use of TAC in conjunction with negative pressure wound therapy with instillation and dwell time (NPWTi-d) for the management of the OA. OBJECTIVE: This case series illustrates the capability, safety, and clinical effectiveness of TAC/NPWTi-d with hypochlorous acid (HOCl) solution. MATERIALS AND METHODS: Three successfully treated cases describe the use of NPWTi-d using HOCl solution for the management of patients with a septic OA. RESULTS: This initial experience suggests instillation of HOCl through the tubing set, in conjunction with the TAC device, is safe and easy to use. This technique decreased the need for more frequent OA lavages in the operating room (OR) after the index procedure, as well as the associated concomitant risks of transporting patients who are critically ill between the SICU and OR. No acute complications related to the TAC device with HOCl were noted. CONCLUSIONS: Based on the results of this study, the authors believe instillation through the TAC device may be the next evolution in the use of abdominal NPWT and programmed intermittent lavage of the peritoneal cavity represents an effective method in the care of patients with a septic OA.

Abdominal compartment syndrome and decompressive laparotomy in children: a 9-year single-center experience.

PURPOSE: Abdominal compartment syndrome (ACS) in children results in 100% mortality if left untreated. Decompressive laparotomy (DL) is the only effective treatment if conservative medical therapies have failed. This study aims to determine the incidence of ACS among pediatric patients who underwent an emergency laparotomy (EL), to describe the effect of DL on clinical and laboratory parameters and, to make a better prediction on fatal outcome, to analyze variables and their association with mortality. METHODS: This retrospective study includes 418 children up to the age of 16 years who underwent EL between January 2010 and December 2018 at our tertiary pediatric referral center. ACS was defined according to the latest guidelines of the World Society of the Abdominal Compartment Syndrome. RESULTS: Fourteen patients had emergency DL for ACS. 6 h preoperatively; median intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) were 22.5 mmHg and 29 mmHg, respectively. After DL, IAP decreased and APP increased, both by an average of 60%. Six patients survived, eight patients had a fatal outcome, resulting in a mortality of 57%. An age under 1 year, weight under the 3rd percentile, an open abdomen treatment, an intestinal resection and an elevated serum lactate > 1.8 mmol/L were associated with an increased relative risk of death. CONCLUSIONS: Improving the outcome in pediatric patients with ACS by removing or attenuating risk factors is difficult. This emphasizes the need for early diagnosis and prompt DL once the diagnosis of ACS is made.

Spontaneous hepatic rupture due to primary amyloidosis.

Spontaneous hepatic rupture is an uncommon cause of haemorrhagic shock and very rarely happens due to amyloidosis. This report describes one such case in which a middle-aged man presented in extremis. He was managed initially with massive transfusion, interventional radiology embolisation and decompressive laparotomy for abdominal compartment syndrome. Subsequent coagulopathy was treated with activated factor VII due to deficient native activity. Serum protein electrophoresis and liver biopsy during his hospital course yielded a diagnosis of amyloidosis, which was treated palliatively with steroids and bortezomib. Despite supportive care, he died 10 days after presentation. This case illustrates the importance of considering an uncommon pathology when a patient presents with a condition in an uncommon way.

Polycompartment syndrome - intra-abdominal pressure measurement.

Intra-abdominal hypertension and the abdominal compartment syndrome are well-known, serious, life-threatening clinical entities in acute care surgery. A common characteristic of these syndromes is the permanent and irreversible damage that may affect the organs which can be found inside the given compartment if quick intervention cannot be provided. All factors which may and can lead to a sudden increase in the intra-abdominal pressure can be found among the triggering factors of abdominal compartment syndrome. Despite the modern and quick diagnostics, and the adequate surgical interventions performed in time, the mortality of this syndrome is extremely high (38-71%). It affects practically all vital organ systems: cardiovascular, respiratory, urinary and central nervous system. There are four major compartments in the human body: the head, the chest, the abdomen and the extremities. When two or more compartments have elevated pressures the name of the clinical entity is polycompartment syndrome, first described in 2007. The only possible way of establishing the diagnosis is to measure the intra-abdominal pressure, a widespread manner of which is the measurement through the bladder. Treatment of abdominal and polycompartment syndrome is nearly always surgical decompression with temporary abdominal wall closure or open abdominal treatment. Clinicians need to be aware of the real existence of polycompartment syndrome and the complex and constant interplay of raised pressure between compartments. This highlights the importance of research and development of new intra-abdominal pressure measurement techniques.

Severe pancreatitis complicated by abdominal compartment syndrome managed with decompressive laparotomy: a case report.

BACKGROUND: Abdominal compartment syndrome (ACS) is an uncommon complication of severe pancreatitis. It is defined as a sustained intraabdominal pressure (IAP) > 20 mmHg (with or without an abdominal perfusion pressure (APP) < 60 mmHg), associated with new organ dysfunction/failure. ACS confers a poor prognosis and should be promptly diagnosed and managed. However, it is often missed on clinical examination, leading to a delay of diagnosis. CASE PRESENTATION: A 38-year old Sri Lankan man presented with severe alcohol-induced pancreatitis associated with abdominal compartment syndrome. Diagnosis was delayed due to false reassurance from clinical examination. The patient was managed with a decompressive laparotomy, after which he required treatment with continuous renal replacement therapy (CRRT), total parenteral nutrition (TPN) and broad-spectrum antibiotics for a prolonged period of time. Despite significant post-operative multi-organ failure, the patient survived. CONCLUSIONS: Early trans-bladder measurement of IAP is important for severe pancreatitis. Serial measurements of IAP should be implemented early when any known risk factor for ACS is present in a critically ill patient.

Editor's Choice - Abdominal Compartment Syndrome after Surgery for Abdominal Aortic Aneurysm: Subgroups, Risk Factors, and Outcome.

OBJECTIVES: Abdominal compartment syndrome (ACS) is a serious complication after abdominal aortic aneurysm (AAA) repair. The aim was to investigate outcome among subgroups and factors associated with outcome, with emphasis on the duration of intra-abdominal hypertension before treatment. METHODS: Since 2008, ACS and decompressive laparotomy (DL) after AAA repair are registered prospectively in the Swedish vascular registry (Swedvasc). Registry data and case records were reviewed. Subgroups were defined by main pathophysiological finding at DL, timing of DL after AAA repair, and treatment modality. RESULTS: During 2008-2015, 120 of 8765 patients undergoing surgery for infrarenal AAA developed post-operative ACS (1.4%). Eighty-three followed ruptured AAA (rAAA); 45 open surgical repairs (OSR) and 38 endovascular (EVAR), and thirty-seven after intact AAA (iAAA); 30 OSR and seven EVAR. The main pathophysiological findings at DL were bowel ischaemia in 27 (23.3%), post-operative bleeding in 34 (29.3%), and general oedema in 55 (47.4%). DL was performed <24 hours after AAA repair in 56 (48.7%), 24-48 hours in 30 (26.1%), and >48 hours in 29 patients (25.2%). The overall 90 day mortality was 50.0%, neither different depending on main pathophysiological finding, nor on the timing of DL. In multivariable regression analysis, age was a predictor of mortality (p = .017), while duration of intra-abdominal hypertension (IAH) prior to DL predicted the need for renal replacement therapy (RRT) (p = .033). DL was performed earlier after EVAR compared with OSR in rAAA (p < .001). CONCLUSIONS: Mortality in ACS was high, irrespective of the main pathophysiological finding and timing of DL. The duration of IAH prior to DL predicted the need for RRT. DL was performed earlier after EVAR than after OSR for rAAA, underlining the importance of monitoring IAP after EVAR for rAAA.