Effect of different types of cerebral perfusion for acute type A aortic dissection undergoing aortic arch procedure, unilateral versus bilateral

Effect of postoperative oxygen therapy regimen modification on oxygenation in patients with acute type A aortic dissection

Objective

In this study, we investigated the effect of various oxygen therapy regimens on oxygenation in patients with acute type A aortic dissection (AAD).

Methods

A quasi-randomized controlled trial was conducted, in which patients with AAD hospitalized for surgery from June to September 2021 were assigned to the control group (patients received conventional oxygen therapy after postoperative mechanical ventilation, weaning, and extubation) and those who were admitted from October to December 2021 were assigned to the observation group [patients underwent optimally adjusted therapy based on the treatment of the control group, which mainly included prioritized elevation of positive end-expiratory pressure (PEEP) and restricted use of the fraction of inspired oxygen (FiO2)].The postoperative oxygenation index, blood gas analysis, and duration of mechanical ventilation were compared between the two groups.

Results

There were significant differences in oxygenation observed at 2 h postoperatively between the groups. 12, 24, and 72 h postoperatively, the oxygenation index varied significantly between the two groups. There were statistically significant differences in the time effects of the oxygenation index and PaO2 between the two groups, as well as significant differences in the length of stay in the intensive care unit.

Conclusion

For the postoperative care of patients with AAD, it is suggested that the minimum FiO2 required for oxygenation of patients be maintained. In addition, it is possible to enhance PEEP as a priority when PaO2 is low.

Clinical outcome of a branch-first approach with a novel continuous whole-brain perfusion strategy for total arch surgery

BACKGROUND

Cerebral protection strategies have been investigated since the introduction of aortic arch surgery and have been modified over the centuries. However, the cerebral protective effects of unilateral and bilateral antegrade cerebral perfusion are similar, with opportunities for further improvement.

METHODS

A total of 30 patients who underwent total arch surgery were enrolled in this study. Patients were assigned to the novel continuous whole-brain or unilateral antegrade cerebral perfusion group according to the cerebral perfusion technique used. Preoperative clinical data and 1-year postoperative follow-up data were collected and analyzed.

RESULTS

There were no significant differences between the two groups in terms of the incidence of permanent neurological deficit, mortality, or therapeutic efficacy. However, the incidence of temporary neurological dysfunction in the novel whole-brain perfusion group was significantly lower than that in the unilateral antegrade cerebral perfusion group.

CONCLUSIONS

In this study, the branch-first approach with a novel whole-brain perfusion strategy had no obvious disadvantages compared with unilateral antegrade cerebral perfusion in terms of cerebral protection and surgical safety. These findings suggest that this new technique is feasible and has application value for total arch surgery.

Cerebral protection in acute type A aortic dissection surgery: a systematic review and meta-analysis

Background

Acute type A aortic dissection (ATAAD) still challenges physicians and warrants emergent surgical management. Two main methods to reduce cerebrovascular events in ATAAD surgeries are antegrade cerebral perfusion (ACP) and retrograde cerebral perfusion (RCP). We conducted a systematic review and meta-analysis to compare the outcomes of ACP and RCP methods during the ATAAD surgery.

Methods

In this study, we searched the databases until March 29th, 2023. Studies that reported the data for comparison of different types of brain perfusion protection during aortic surgery in patients with ATAAD were included.

Results

Twenty-six studies met the eligibility criteria. All studies had a low risk of bias as they were evaluated by the Joanna Briggs Institute (JBI) critical appraisal tool. Eventually, we included 26 studies in the current meta-analysis, and a total of 13,039 patients were evaluated. The calculated risk ratio (RR) for permanent neurologic dysfunction (PND) in ACP and RCP comparison was RR =1.23, 95% confidence interval (CI): (0.84, 1.80) (P value =0.2662), and in unilateral ACP (uACP) and bilateral ACP (bACP) was RR =1.2786, 95% CI: (0.7931, 2.0615) (P value =0.3132). When comparing the ACP-RCP and uACP-bACP groups, significant differences were found between ACP-RCP the groups in terms of circulatory arrest time (P value =0.0017 and P value =0.1995, respectively), cardiopulmonary bypass time (P value =0.5312 and P value =0.7460, respectively), intensive care unit (ICU)-stay time (P value =0.2654 and P value =0.0099), crossclamp time (P value =0.6228 and P value =0.2625), and operative mortality (P value =0.9368 and P value =0.2398, respectively), and when comparing the u-ACP and b-ACP groups for transient neurologic deficit (TND), an RR of 1.32, 95% CI: (1.05, 1.67) (P value =0.0199). The results showed high heterogeneity and no publication bias.

Conclusions

This study demonstrated that the ACP and RCP are both safe and acceptable techniques to use in emergent settings. The uACP technique is equivalent to bACP in terms of PND and mortality, however, uACP is preferred over bACP in terms of TND.

Meta-analysis: Bilateral and Unilateral Cerebral Perfusion in Type A Dissection

BACKGROUND

 This meta-analysis compared the outcomes of bilateral cerebral perfusion (BCP) and unilateral cerebral perfusion (UCP) in aortic surgery for acute type A aortic dissection.

METHODS

 A systematic literature search identified 12 studies involving 4,547 patients. Pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated to analyze perioperative characteristics, short-term mortality rates, and postoperative neurological complications.

RESULTS

 No significant differences were found between the BCP and UCP groups in terms of cardiopulmonary bypass time, aortic cross clamp time, lowest body temperature, and lower body circulatory arrest time. Short-term mortality rates (OR [95% CI] = 0.87 [0.64-1.19], p = 0.40) and permanent neurological deficits (OR [95% CI] = 1.01 [0.69-1.47], p = 0.96) were comparable between the groups. However, subgroup analysis of studies exclusively involving total arch replacement showed a lower short-term mortality rate (OR [95% CI] = 0.42 [0.28-0.63], p < 0.01) and permanent neurological deficits (OR [95% CI] = 0.53 [0.30-0.92], p = 0.03) in the BCP group. The BCP group also had a lower rate of temporary neurological deficits (OR [95% CI] = 0.70 [0.53-0.93], p = 0.01), particularly in studies exclusively involving total arch replacement (OR [95% CI] = 0.58 [0.40-0.85], p < 0.01).

CONCLUSION

 This meta-analysis suggests that BCP and UCP yield comparable outcomes. However, BCP may be associated with lower short-term mortality rates and reduced incidence of neurological complications, particularly in cases requiring total arch replacement. BCP should be considered as a preferred cerebral perfusion in specific patient populations.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

The impact of circulatory arrest with selective antegrade cerebral perfusion on brain functional connectivity and postoperative cognitive function

Aortic surgery is one of the most challenging types of surgeries, which is possibly related to cognitive sequelae. We aimed to investigate the changes in resting-state functional connectivity (rsFC) associated with intraoperative circulatory arrest (CA) in aortic surgery, exploring the relationship between the altered connectivity and postoperative cognitive functions. Thirty-eight patients participated in this study (14 with CA, 24 without). Functional magnetic resonance imaging was scanned on the fifth day after surgery or after the resolution of delirium if it was developed. We assessed the differences in the development of postoperative cognitive changes and rsFC between patients with and without CA. The occurrence of postoperative delirium and postoperative cognitive dysfunction was not significantly different between the patients with and without the application of CA. However, patients with CA showed increased in posterior cingulate cortex-based connectivity with the right superior temporal gyrus, right precuneus, and right hippocampus, and medial prefrontal cortex-based connectivity with the dorsolateral prefrontal cortex. The application of moderate hypothermic CA with unilateral antegrade cerebral perfusion is unlikely to affect aspects of postoperative cognitive changes, whereas it may lead to increased rsFC of the default mode network at a subclinical level following acute brain insults.

Association between Bilateral Selective Antegrade Cerebral Perfusion and Postoperative Ischemic Stroke in Patients with Emergency Surgery for Acute Type A Aortic Dissection-Single Centre Experience

Acute type A aortic dissection (ATAAD) is a surgical emergency with a mortality of 1-2% per hour. Since its discovery over 200 years ago, surgical techniques for repairing a dissected aorta have evolved, and with the introduction of hypothermic circulatory arrest and cerebral perfusion, complex techniques for replacing the entire aortic arch were possible. However, postoperative neurological complications contribute significantly to mortality in this group of patients. The aim of this study was to determine the association between different bilateral selective antegrade cerebral perfusion (ACP) times and the incidence of postoperative ischemic stroke in patients with emergency surgery for ATAAD. Patients with documented hemorrhagic or ischemic stroke, clinical signs of stroke or neurological dysfunction prior to surgery, that died on the operating table or within 48 h after surgery, from whom the postoperative neurological status could not be assessed, and with incomplete medical records were excluded from this study. The diagnosis of postoperative stroke was made using head computed tomography imaging (CT) when clinical suspicion was raised by a neurologist in the immediate postoperative period. For selective bilateral antegrade cerebral perfusion, we used two balloon-tipped cannulas inserted under direct vision into the innominate artery and the left common carotid artery. Each cannula is connected to a separate pump with an independent pressure line. Near-infrared spectroscopy was used in all cases for cerebral oxygenation monitoring. The circulatory arrest was initiated after reaching a target core temperature of 25-28 °C. In total, 129 patients were included in this study. The incidence of postoperative ischemic stroke documented on a head CT was 24.8% (31 patients), and postoperative death was 20.9% (27 patients). The most common surgical technique performed was supravalvular ascending aorta and Hemiarch replacement with a Dacron graft in 69.8% (90 patients). The mean cardiopulmonary bypass time was 210 +/- 56.874 min, the mean aortic cross-clamp time was 114.775 +/- 34.602 min, and the mean cerebral perfusion time was 37.837 +/- 18.243 min. Using logistic regression, selective ACP of more than 40 min was independently associated with postoperative ischemic stroke (OR = 3.589; 95%CI = 1.418-9.085; p = 0.007). Considering the high incidence of postoperative stroke in our study population, we concluded that bilateral selective ACP should be used with caution, especially in patients with severely calcified ascending aorta and/or aortic arch and supra-aortic vessels. All efforts should be made to minimize the duration of circulatory arrest when using bilateral selective ACP with a target of less than 30 min, in hypothermia, at a body temperature of 25-28 °C.

Cerebral Protection Strategies and Stroke in Surgery for Acute Type A Aortic Dissection

Background: Perioperative stroke remains a devastating complication in the operative treatment of acute type A aortic dissection. To reduce the risk of perioperative stroke, different perfusion techniques can be applied. A consensus on the preferred cerebral protection strategy does not exist. Methods: To provide an overview about the different cerebral protection strategies, literature research on Medline/PubMed was performed. All available original articles reporting on cerebral protection in surgery for acute type A aortic dissection and neurologic outcomes since 2010 were included. Results: Antegrade and retrograde cerebral perfusion may provide similar neurological outcomes while outperforming deep hypothermic circulatory arrest. The choice of arterial cannulation site and chosen level of hypothermia are influencing factors for perioperative stroke. Conclusions: Deep hypothermic circulatory arrest is not recommended as the sole cerebral protection technique. Antegrade and retrograde cerebral perfusion are today’s standard to provide cerebral protection during aortic surgery. Bilateral antegrade cerebral perfusion potentially leads to superior outcomes during prolonged circulatory arrest times between 30 and 50 min. Arterial cannulation sites with antegrade perfusion (axillary, central or carotid artery) in combination with moderate hypothermia seem to be advantageous. Every concept should be complemented by adequate intraoperative neuromonitoring.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Unilateral versus bilateral anterograde cerebral perfusion in acute type A aortic dissection repair: A systematic review and meta-analysis

OBJECTIVES

The aim of the study is to compare the safety and efficacy of unilateral anterograde cerebral perfusion (UACP) and bilateral anterograde cerebral perfusion (BACP) for acute type A aortic dissection (ATAAD).

METHODS

A systematic review of the MEDLINE (PubMed), Scopus, and Cochrane Library databases (last search: August 7th, 2021) was performed according to the PRISMA statement. Studies directly comparing UACP versus BACP for ATAAD were included. Random-effects meta-analyses were performed.

RESULTS

Eight retrospective cohort studies were identified, incorporating 2416 patients (UACP: 843, BACP: 1573). No statistically significant difference was observed regarding in-hospital mortality (odds ratio [OR]:1.05 [95% Confidence Interval (95% CI):0.70-1.57]), permanent neurological deficit (PND) (OR: 0.94 [95% CI: 0.52-1.70]), transient neurological deficit (TND) (OR: 1.37 [95% CI: 0.98-1.92]), renal failure (OR: 0.96 [95% CI: 0.70-1.32]), and re-exploration for bleeding (OR: 0.77 [95% CI: 0.48-1.22]). Meta-regression analysis revealed that PND and TND were not influenced by differences in rates of total arch repair, Bentall procedure, and concomitant CABG in UACP and BACP groups. Cardiopulmonary bypass time (Standard Mean Difference [SMD]: -0.11 [95% CI: -0.22, 0.44]), Cross clamp time (SMD: -0.04 [95% CI: -0.38, 0.29]), and hypothermic circulatory arrest time (SMD: -0.12 [95% CI: -0.55, 0.30]) were comparable between UACP and BACP. Intensive care unit stay was shorter in BACP arm (SMD:0.16 [95% CI: 0.01, 0.31]); however, length of hospital stay was shorter in UACP arm (SMD: -0.25 [95% CI: -0.45, -0.06]).

CONCLUSIONS

UACP and BACP had similar results in terms of in-hospital mortality, PND, TND, renal failure, and re-exploration for bleeding rate in patients with ATAAD. ICU stay was shorter in the BACP arm while LOS was shorter in the UACP arm.

Incidence, Risk Factors and Outcomes of Postoperative Headache After Stanford Type a Acute Aortic Dissection Surgery

Background: Postoperative headache (POH) is common in clinical practice, however, no studies about POH after Stanford type A acute aortic dissection surgery (AADS) exist. This study aims to describe the incidence, risk factors and outcomes of POH after AADS, and to construct two prediction models.

Methods: Adults who underwent AADS from 2016 to 2020 in four tertiary hospitals were enrolled. Training and validation sets were randomly assigned according to a 7:3 ratio. Risk factors were identified by univariate and multivariate logistic regression analysis. Nomograms were constructed and validated on the basis of independent predictors.

Results: POH developed in 380 of the 1,476 included patients (25.7%). Poorer outcomes were observed in patients with POH. Eight independent predictors for POH after AADS were identified when both preoperative and intraoperative variables were analyzed, including younger age, female sex, smoking history, chronic headache history, cerebrovascular disease, use of deep hypothermic circulatory arrest, more blood transfusion, and longer cardiopulmonary bypass time. White blood cell and platelet count were also identified as significant predictors when intraoperative variables were excluded from the multivariate analysis. A full nomogram and a preoperative nomogram were constructed based on these independent predictors, both demonstrating good discrimination, calibration, clinical usefulness, and were well validated. Risk stratification was performed and three risk intervals were defined based on the full nomogram and clinical practice.

Conclusions: POH was common after AADS, portending poorer outcomes. Two nomograms predicting POH were developed and validated, which may have clinical utility in risk evaluation, early prevention, and doctor-patient communication.