Moderate Hypothermia Circulatory Arrest Research Articles

Moderate hypothermia circulatory arrest as a brain-protective strategy for type A aortic dissection.

Brain-protective strategies for acute type A aortic dissection (TAAD) remain controversial. Moderate hypothermia circulatory arrest (MHCA) without cerebral perfusion is not commonly used. However, we aimed to assess its safety and efficacy in 358 patients who underwent hemiarch replacement with MHCA for acute type A aortic dissection at our institution from August 2012 to August 2022. Clinical outcomes were compared according to circulatory arrest time [≤15 min (S group, n = 52) vs ≥16 min (L group, n = 306)]. The primary outcome was postoperative stroke. The S group had more older patients (72.5 vs 68.8 years; P = 0.04), a greater incidence of carotid artery malperfusion (21% vs 11%; P = 0.043) and a lower body mass index (21.7 vs 23.6 kg/m2; P < 0.01) and hemodynamic instability (3.8% vs 16%; P = 0.02) than the L group. The incidence of postoperative stroke (7.7% vs 12%; P = 0.33) and the rate of 30-day mortality (5.8% vs 6.5%; P = 0.83) did not significantly differ between groups. After adjusting for all potential confounding factors pre- and intraoperatively, there was no significant difference in postoperative outcomes between groups. MHCA alone for TAAD had comparable postoperative outcomes with circulatory arrest times under and over 15 min. However, longer arrest times were associated with a higher risk of stroke.

"Brain-First" Total Body Retrograde Perfusion and Retrograde Cerebral Perfusion in Hemi-Arch Replacement

Objective: The purpose of this study is to compare the early outcomes of brain-first total body retrograde perfusion (Bf-TBRP) in comparison with reverse cerebral perfusion (RCP) under moderate hypothermia circulatory arrest (MHCA) for hemi-arch replacement surgery. Methods: We analyzed the data of 88 patients who underwent hemi-arch replacement with Bf-TBRP (n = 18) or RCP (n = 70) under MHCA at West China Hospital of Sichuan University between 1 January 2020, and 31 July 2022. In-hospital mortality, neurological deficits, and other adverse events were recorded, which were evaluated with logistic regression to determine risk factors. Results: There was no significant difference between the Bf-TBRP and RCP groups in in-hospital mortality, cardiac events, neurological deficits, dialysis, gastrointestinal complications, and paralysis (p &gt; 0.05). The Bf-TBRP group was associated with significantly shorter hospital stay [Bf-TBRP: 8 d (interquartile range (IQR), 7–10) vs. RCP: 10 d (IQR, 8–13), p = 0.03] and fewer platelet transfusions [Bf-TBRP: 1.0 (IQR, 0–1.0) vs. RCP: 1.0 (IQR, 1.0–2.0), p = 0.05] than the RCP group. On multivariable logistic regression analysis, emergency surgery (p = 0.05) and surgery duration (p = 0.03) were determined to be risk factors. Conclusions: The study showed that Bf-TBRP is a safe technique for patients undergoing hemi-arch replacement with MHCA.

Retrograde Inferior Vena caval Perfusion for Total Aortic arch Replacement Surgery (RIVP-TARS): study protocol for a multicenter, randomized controlled trial

BackgroundDuring total aortic arch replacement surgery (TARS) for patients with acute type A aortic dissection, the organs in the lower body, such as the viscera and spinal cord, are at risk of ischemia even when antegrade cerebral perfusion (ACP) is performed. Combining ACP with retrograde inferior vena caval perfusion (RIVP) during TARS may improve outcomes by providing the lower body with oxygenated blood.MethodsThis study is designed as a multicenter, computer-generated, randomized controlled, assessor-blind, parallel-group study with a superiority framework in patients scheduled for TARS. A total of 636 patients will be randomized on a 1:1 basis to a moderate hypothermia circulatory arrest (MHCA) group, which will receive selective ACP with moderate hypothermia during TARS; or to an RIVP group, which will receive the combination of RIVP and selective ACP under moderate hypothermia during TARS. The primary outcome will be a composite of early mortality and major complications, including paraplegia, postoperative renal failure, severe liver dysfunction, and gastrointestinal complications. All patients will be analyzed according to the intention-to-treat protocol.DiscussionThis study aims to assess whether RIVP combined with ACP leads to superior outcomes than ACP alone for patients undergoing TARS under moderate hypothermia. This study seeks to provide high-quality evidence for RIVP to be used in patients with acute type A aortic dissection undergoing TARS.Trial registrationClinicaltrials.gov, ID: NCT03607786. Registered on 30 July 2018.

Moderate Hypothermic Circulatory Arrest with Antegrade Cerebral Perfusion for Rapid Total Arch Replacement in Acute Type A Aortic Dissection

The optimal hypothermic level during circulatory arrest is controversial. The aim of our study was to comprehensively assess the impact of moderate hypothermic circulatory arrest with antegrade cerebral perfusion (ACP) on total aortic arch replacement. From 2010 to 2013, data were collected from 99 consecutive patients with acute type A aortic dissection. All patients underwent total arch replacement plus frozen elephant trunk procedure. There were 51 patients in the deep hypothermia circulatory arrest (DHCA) group and 47 in the moderate hypothermia circulatory arrest (MHCA) group. Either unilateral or bilateral ACP was applied for cerebral protection. Perioperative data and measured outcomes were compared. Overall mean circulatory arrest time was 29.9 ± 6.0 minutes. Temporary neurologic dysfunction incidence was lower in the MHCA group compared with the DHCA group (21.3 vs. 40.4%, p = 0.041). The total 30-day mortality was 17.2% (14.9 vs. 19.2%, p = 0.568) and permanent neurologic dysfunction morbidity was 3.0% overall. In MHCA, less blood products were used than in DHCA. Moderate hypothermia was a protective factor for the composite outcome of temporary and permanent neurologic dysfunctions (odds ratio = 0.385; 95% confidence interval = 0.162-0.919). Hypothermic level did not significantly affect the perioperative alanine aminotransferase and serum creatinine levels. Within a short circulatory arrest time, MHCA combined with ACP seemed to be a safe and effective method to protect cerebral and visceral organs during total aortic arch replacement.