Uncertainty of axillary artery perfusion during surgery for acute aortic dissection

Cerebral hypoperfusion resulting from improper cannulation positioning during aortic dissection surgery: a case report

BACKGROUND

Selective antegrade cerebral perfusion (sACP) is a crucial cerebral protection technique employed during aortic dissection surgeries involving cardiopulmonary bypass. However, postoperative neurological complications, particularly those related to cannulation issues and perfusion problems, remain a significant concern.

CASE PRESENTATION

This case report details an unusual instance where a 38-year-old male patient with Marfan syndrome experienced cerebral hypoperfusion during emergency surgery for Stanford Type A aortic dissection. Despite following standard protocols, a significant drop in regional cerebral oxygen saturation (rSO2) and abnormal blood pressure fluctuations were observed shortly after initiating sACP via the innominate artery. After initial attempts to optimize perfusion flow proved ineffective, the cannulation position was adjusted, leading to improvements. Nevertheless, the patient subsequently exhibited signs of cerebral hypoperfusion and was found to have suffered a new cerebral infarction.

CONCLUSIONS

This case report underscores the importance of precise cannula placement during sACP procedures and the dire consequences that can arise from improper positioning. It emphasizes the need for continuous monitoring and prompt intervention in cases of abnormal cerebral oxygenation and blood pressure, as well as the value of considering cannulation-related issues as potential causes of postoperative neurological complications.

Extra-anatomic revascularization and a new cannulation strategy for preoperative cerebral malperfusion due to severe stenosis or occlusion of supra-aortic branch vessels in acute type A aortic dissection

Objectives

Acute type A aortic dissection (ATAAD) with severe stenosis or occlusion of the true lumen of aortic arch branch vessels often leads to an increased incidence of severe postsurgical neurological complications and mortality rate. In this study, we aimed to introduce our institutional extra-anatomic revascularization and cannulation strategy with improved postoperative outcomes for better management of patients with cerebral malperfusion in the setting of ATAAD.

Methods

Twenty-eight patients with ATAAD complicated by severe stenosis or occlusion of the aortic arch branch vessels, as noted on combined computed tomography angiography of the aorta and craniocervical artery, between January 2021 and June 2022 were included in this study. Basic patient characteristics, surgical procedures, hospitalization stays, and early follow-up results were analyzed.

Results

The median follow-up duration was 16.5 months (interquartile range: 11.5-20.5), with a 100% completion rate. The 30-day mortality rates was 7.1% (2/28 patients); two patients had multiple cerebral infarctions on preoperative computed tomography and persistent coma. Postoperative transient neurological dysfunction occurred in 10.7% (3/28) of the patients, and no new permanent neurological dysfunction occurred. Of all the patients, 3.6% (1/28) had novel acute renal failure. No other deaths, secondary surgeries, or serious complications occurred during the early follow-up period.

Conclusions

Use of extra-anatomic revascularization and a new cannulation strategy before cardiopulmonary bypass is safe and feasible and may reduce the high incidence of postoperative neurological complications in patients with ATAAD and cerebral malperfusion.

Impact of direct carotid artery perfusion in acute type A aortic dissection involving the common carotid artery

Objectives

Acute type A aortic dissection complicated with brain ischemia is associated with significantly higher mortality risks. Even if rescued with central aortic repair, some patients develop permanent postoperative neurological deficiency postoperatively. We recently introduced direct common carotid artery perfusion for acute type A aortic dissection involving the common carotid artery. This study introduced this technique to prevent postoperative neurological deficiency by comparing brain protection strategies.

Methods

Among 91 acute type A aortic dissection patients treated at our hospital during August 2015–October 2020, the common carotid artery was involved in 19 (21%), which had > 90% stenosis in either of the carotid arteries on preoperative contrast-enhanced computed tomography. Twelve patients underwent conventional selective cerebral perfusion during August 2015–December 2018 and seven patients underwent direct carotid artery perfusion during January 2019–October 2020. We assessed patient characteristics, surgical courses, clinical outcomes, and neurological outcomes.

Results

The mean age was 69 (range 39–84) years; 17 patients were male (89%). Eight patients (42%) had neurological symptoms. Concomitant procedures, postoperative neurological symptoms, and late mortality were significantly associated with conventional selective cerebral perfusion. Five selective cerebral perfusion patients experienced worsened neurological symptoms and two died of broad cerebral ischemia. No direct carotid artery perfusion patient died during hospitalization or experienced worsened neurological outcomes.

Conclusions

Direct carotid artery perfusion may be useful in aortic dissection with brain ischemia because it does not aggravate neurological symptoms and is not associated with intraoperative cerebral infarction. However, it may be ineffective when cerebral infarction has already developed.

A modified axillo-femoral perfusion for acute type a aortic dissection accompanied with lower limb malperfusion

Background

Lower limb malperfusion accompanied with acute type A dissection (AAD) is reported to be an independent predictor for mortality. Timely treatment is required. However, staged approach to restore the perfusion of the ischemic leg before aortic repair has a continuously increase risk of aortic rupture. Aortic repair under isolated axillary artery perfusion also has the risk of prolonging leg ischemia. Here we introduce our experience in performing axillo-femoral perfusion, which is supposed to bring benefits for treating lower limb malperfuison.

Methods

Thirty patients who suffered AAD accompanied by lower limb ischemia enrolled in our study. All patients received aortic repair as soon as possible using the modified axillo-femoral perfusion approach. The cardiopulmonary bypass and cooling started with the right axillary artery perfusion. Then the femoral artery of the ischemic side was exposed and sewn to a graft connected with another inflow cannula. The rectal temperature was about 31 °C when the femoral perfusion started. The perfusion of the ischemic legs preoperative was estimated after the surgery by the clinical signs, the saturation of the distal-limb, and computed tomography scan.

Results

Twenty-eight patients got good perfusion of the lower body after the surgery. Two patients received femoral-femoral artery bypass immediately after surgery because of the thrombosis in the right common iliac artery, without further injury. No peripheral vessels damage occurred, and no compartment fasciotomy or amputation needed. One patient died for the sepsis and the subsequent multi organ failure 28 days postoperative.

Conclusions

The modified axllio-femoral perfusion could restore the lower limbs’ perfusion simultaneously during the aortic surgery without neither delaying dissection repair nor prolonging the ischemic time. It is a simple, but safe and effective technique.

sArterial cannulation to establish cardiopulmonary bypass during surgery for acute aortic dissection

A cannulation strategy in surgery for Stanford type A acute aortic dissection (AAAD) is integral for patient survival. Femoral cannulation has been the standard option for cannulation; however, there is increasing evidence that retrograde perfusion with femoral cannulation is associated with worse clinical outcomes, and new cannulation sites have been introduced in surgery for AAAD. Although axillary artery cannulation and central cannulation via the ascending aorta have become more popular than femoral access in recent years, adverse events have been reported and shifting cannulation sites during surgery are recommended by some surgeons. Therefore, it is beneficial for surgeons to broaden their knowledge about cannulation technology for AAAD. In this review, we discuss the various methods of cannulation for AAAD.

Cerebral malperfusion in acute aortic dissection

Cerebral malperfusion in association with acute type A aortic dissection is uncommon but can have a considerable effect on the outcome of treatment. Successful treatment requires the individual and effective removal of each of the factors associated with malperfusion. In addition to the conventional surgical procedures, endovascular treatment has become an option for restoring perfusion. However, artificial perfusion and/or surgical procedures can lead to new malperfusion, which is not necessarily apparent to surgeons and which is difficult to predict. Thus, a number of modalities need to be applied to monitoring the current status of perfusion to enable timely treatment. Since each of the diagnostic modalities has its merits and demerits, one should use them effectively while being mindful of the pitfalls. In addition, a delay in the diagnosis in the pre-hospital stage is an important determinant of the surgical outcomes of aortic dissection. Portable echocardiography, which has been recently developed, may be useful for improving this situation. However, an early diagnosis largely depends on the physician's awareness and basic echocardiography skills. Surgeons should make general physicians aware of this message.