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.

Is Deep Hypothermic Cardiac Arrest Mandatory in Aortic Arch Surgeries?

Cannulation strategies in aortic arch surgeries are a matter of immense discussion. Majority of time deep hypothermic circulatory arrest (DHCA) is the way out, but it does come with its set of demerits. Here we demonstrate a case with aortic arch dissection dealt with dual cannulation strategy in axillary and femoral artery without need for DHCA and ensuring complete neuroprotection of brain and spinal cord without hinderance of time factor. Inception of new ideas like this may decrease the need for DHCA and hence its drawbacks, thus decreasing the morbidity and mortality associated.

Early outcome of simplified total arch reconstruction under mild hypothermia (30-32 °C) with distal aortic perfusion

OBJECTIVE

We designed a simplified total arch reconstruction (s-TAR) technique which could be performed under mild hypothermia (30-32 °C) with distal aortic perfusion. This study aimed to compare its efficacy of organ protection with the conventional total arch reconstruction (c-TAR).

METHODS

We reviewed the clinical data of 195 patients who had ascending aortic aneurysm with extended aortic arch dilation and underwent simultaneous ascending aorta replacement and TAR procedure between January 2018 and December 2022 in our center. 105 received c-TAR under moderate hypothermia (25-28 °C) with circulatory arrest (c-TAR group); rest 90 received s-TAR under mild hypothermia (30-32 °C) with distal aortic perfusion (s-TAR group).

RESULTS

The s-TAR group demonstrated shorter CPB time, cross-clamp time and lower body circulatory arrest time compared with the c-TAR group. The 30-day mortality was 2.9% for the c-TAR group and 1.1% for the s-TAR group (P = 0.043). The mean duration of mechanical ventilation was shorter in the s-TAR group. Paraplegia was observed in 4 of 105 patients (3.8%) in the c-TAR group, while no such events were observed in the s-TAR group. The incidence of temporary neurologic dysfunction was significantly higher in the c-TAR group. The incidence of permanent neurologic dysfunction also showed a tendency to be higher in the c-TAR group, without statistical significance. Furthermore, the incidence of reoperation for bleeding were significantly lower in the s-TAR group. The rate of postoperative hepatic dysfunction and all grades of AKI was remarkably lower in the s-TAR group. The 3-year survival rate was 95.6% in the s-TAR group and 91.4% in the c-TAR group.

CONCLUSIONS

s-TAR under mild hypothermia (30-32℃) with distal aortic perfusion is associated with lower mortality and morbidity, offering better neurological and visceral organ protection compared with c-TAR.

OUP accepted manuscript

Consensus regarding optimal cerebral protection strategy in aortic arch surgery is lacking. We therefore performed a systematic review and meta-analysis to assess outcome differences between unilateral antegrade cerebral perfusion (ACP), bilateral ACP, retrograde cerebral perfusion (RCP) and deep hypothermic circulatory arrest (DHCA). A systematic literature search was performed in Embase, Medline, Web of Science, Cochrane and Google Scholar for all papers published till February 2021 reporting on early clinical outcome after aortic arch surgery utilizing either unilateral, bilateral ACP, RCP or DHCA. The primary outcome was operative mortality. Other key secondary endpoints were occurrence of postoperative disabling stroke, paraplegia, renal and respiratory failure. Pooled outcome risks were estimated using random-effects models. A total of 222 studies were included with a total of 43 720 patients. Pooled postoperative mortality in unilateral ACP group was 6.6% [95% confidence interval (CI) 5.3–8.1%], 9.1% (95% CI 7.9–10.4%), 7.8% (95% CI 5.6–10.7%), 9.2% (95% CI 6.7–12.7%) in bilateral ACP, RCP and DHCA groups, respectively. The incidence of postoperative disabling stroke was 4.8% (95% CI 3.8–6.1%) in the unilateral ACP group, 7.3% (95% CI 6.2–8.5%) in bilateral ACP, 6.4% (95% CI 4.4–9.1%) in RCP and 6.3% (95% CI 4.4–9.1%) in DHCA subgroups. The present meta-analysis summarizes the clinical outcomes of different cerebral protection techniques that have been used in clinical practice over the last decades. These outcomes may be used in advanced microsimulation model. These findings need to be placed in the context of the underlying aortic disease, the extent of the aortic disease and other comorbidities.

Prospero registration number: CRD42021246372

METC: MEC-2019-0825

Deep Hypothermic Circulatory Arrest for Emergency Repair of Type A Aortic Dissection in a Patient with Cold Agglutinins

Cold agglutinins (CA) are auto-antibodies that adhere to erythrocytes in cold temperatures, and can result in agglutination of red blood cells. This process can cause complement-mediated intravascular hemolysis, which can be catastrophic. We describe a patient who developed CA during initiation of deep hypothermic circulatory arrest for emergent repair of Type A aortic dissection. The patient was found to have anti-I and anti-C antibodies and a positive direct Coombs test. CA resolved with re-warming, and resulted in no adverse events.

Antegrade and Retrograde Cerebral Perfusion During Acute Type A Aortic Dissection Repair in 290 Patients

AIM

Hypothermia and selective brain perfusion is used for brain protection during an acute type A aortic dissection (ATAAD) correction. We compared the outcomes between antegrade and retrograde cerebral perfusion techniques after ATAAD surgery.

METHOD

Between January 1995 and August 2017, 290 patients underwent ATAAD repair under deep hypothermic circulatory arrest/retrograde cerebral perfusion (DHCA/RCP) in 173 patients and moderate hypothermic circulatory arrest/antegrade cerebral perfusion (MHCA/ACP) in 117 patients. Outcomes of interest were: 30-day mortality, new-onset postoperative neurological complications, and length of intensive care unit (ICU) and in-hospital stays.

RESULTS

No differences were observed between the preoperative details of both groups (p>0.05). Thirty-day (30-day) mortality did not differ between groups (RCP vs ACP, 22% vs 21.4%; p=0.90). New-onset postoperative permanent neurological dysfunctions and coma was similar in two group in 6.9% versus 10.3% of patients and 3.8% versus 6.8% patients of patients, respectively (p=0.69). The incidence of 30-day mortality and new postoperative neurological complications were similar in the RCP and ACP groups (odds ratio [OR], 1.0; 95% confidence interval [CI], 0.39-2.83 [p=0.91] and OR, 1.7; 95% CI, 0.87-3.23 [p=0.11], respectively). There was no difference between length of stay in the ICU and overall stay in hospital between the RCP and ACP groups (p=0.31 and p=0.14, respectively). No difference in survival rate was observed between the RCP and ACP groups (hazard ratio, 1.2; 95% CI, 0.76-2.01 [p=0.39]).

CONCLUSIONS

Thirty-day (30-day) mortality rate, new-onset postoperative neurological dysfunctions, ICU stay, and in-hospital stay did not differ between the MHCA/ACP and DHCA/RCP groups after ATAAD correction. Although the rates of 30-day mortality and postoperative neurological complications were high after ATAAD repair, ACP had no advantages over the RCP technique.

Open Tacking of a Migrated Thoracic Endovascular Aortic Graft

Complications of thoracic endovascular aortic repair (TEVAR) are beginning to emerge as novel vascular issues. While endovascular solutions exist for most, some graft complications require a more traditional open solution. These operations are most commonly performed for endoleak or disease progression. Much less frequently observed is the migration of the endograft requiring open reintervention. Herein we present a case of a proximally migrated TEVAR graft, which required open fixation under deep hypothermic circulatory arrest (DHCA).

Cerebral mitochondrial dysfunction associated with deep hypothermic circulatory arrest in neonatal swine

OBJECTIVES

Controversy remains regarding the use of deep hypothermic circulatory arrest (DHCA) in neonatal cardiac surgery. Alterations in cerebral mitochondrial bioenergetics are thought to contribute to ischaemia-reperfusion injury in DHCA. The purpose of this study was to compare cerebral mitochondrial bioenergetics for DHCA with deep hypothermic continuous perfusion using a neonatal swine model.

METHODS

Twenty-four piglets (mean weight 3.8 kg) were placed on cardiopulmonary bypass (CPB): 10 underwent 40-min DHCA, following cooling to 18°C, 10 underwent 40 min DHCA and 10 remained at deep hypothermia for 40 min; animals were subsequently rewarmed to normothermia. 4 remained on normothermic CPB throughout. Fresh brain tissue was harvested while on CPB and assessed for mitochondrial respiration and reactive oxygen species generation. Cerebral microdialysis samples were collected throughout the analysis.

RESULTS

DHCA animals had significantly decreased mitochondrial complex I respiration, maximal oxidative phosphorylation, respiratory control ratio and significantly increased mitochondrial reactive oxygen species (P < 0.05 for all). DHCA animals also had significantly increased cerebral microdialysis indicators of cerebral ischaemia (lactate/pyruvate ratio) and neuronal death (glycerol) during and after rewarming.

CONCLUSIONS

DHCA is associated with disruption of mitochondrial bioenergetics compared with deep hypothermic continuous perfusion. Preserving mitochondrial health may mitigate brain injury in cardiac surgical patients. Further studies are needed to better understand the mechanisms of neurological injury in neonatal cardiac surgery and correlate mitochondrial dysfunction with neurological outcomes.

[Resection for the Recurrence of Hepatocellular Carcinoma in the Inferior Vena Cava and Right Atrium under Deep Hypothermic Circulatory Arrest]

A 77-year-old man underwent extended right lobectomy of the liver for rupture of hepatocellular carcinoma. Recurrence in the inferior vena cava andright atrium was noted 30 months after surgery. We performedextirpation of this tumor thrombosis under retrograde cerebral perfusion during deep hypothermic circulatory arrest. The pericardium was cut through sternotomy, and cooling was initiated. After cardiac arrest at 20.4°C, the inferior vena cava was separated. An incision was made in the right atrium andthe tumor thrombus was extirpated. In the meantime, brain protection was maintainedby retrograde cerebral perfusion. The patient was discharged on day 12 without postoperative complications. He remains alive 6 months after surgery without recurrence. This procedure prevented pulmonary embolism due to tumor thrombosis release. It was also possible to perform the procedure with retrograde cerebral perfusion.

Floating thrombus in the ascending aorta causing repeated arterial embolisms

Free-floating thrombus in an otherwise normal ascending aorta is a rare finding. We report the case of a 61-year-old woman admitted for brain and peripheral arterial embolisms. Echocardiography was not able to detect the source of embolus. Computed tomographic scan demonstrated a large floating mass attached to the posterior wall of the distal ascending aorta. The thrombus was successfully removed with the patient under deep hypothermic circulatory arrest. Some aspects regarding pathogenesis, diagnosis and treatment are discussed.

[Surgical Treatment of Right Atrial Malignant Tumor Thrombus Under Deep Hypothermia with Intermittent Circulatory Arrest;Report of Two Cases]

Right atrial tumor thrombus is rare in patients with visceral malignant tumors and can cause right heart failure or sudden death. We present 2 cases of right atrial tumor thrombus treated under deep hypothermic intermittent circulatory arrest (DHICA). A 45-year-old man with right heart failure was diagnosed with right renal cancer extending to the right atrium. Computed tomography revealed no metastasis. He underwent right nephrectomy and tumor thrombus resection under DHICA. He was discharged on postoperative day 11 in good clinical course. A 67-year-old woman with hepatitis C virus liver cirrhosis( Child-Pugh A) was diagnosed with hepatocellular carcinoma and right atrial tumor. She underwent S8 and tumor thrombus resection under DHICA. Hemorrhagic diathesis was controlled using fresh frozen plasma transfusion. She was discharged on postoperative day 24 without liver failure. In cases of atrial tumor thrombus resection, DIHCA may be useful to achieve a bloodless operation field because the procedure is relatively simple and the primary disease need not be considered.

Association of nadir oxygen delivery on cardiopulmonary bypass with serum glial fibrillary acid protein levels in paediatric heart surgery patients

OBJECTIVES

Protecting the brain during cardiac surgery is a major challenge. We evaluated associations between nadir oxygen delivery (DO2) during paediatric cardiac surgery and a biomarker of brain injury, glial fibrillary acidic protein (GFAP).

METHODS

Blood samples were obtained during a prospective, single-centre observational study of children undergoing congenital heart surgery with cardiopulmonary bypass (CPB) (2010-2011). Remnant blood samples, collected serially prior to cannulation for bypass and until incision closure, were analysed for GFAP levels. Perfusion records were reviewed to calculate nadir DO2. Linear regression analysis was used to assess the association between nadir DO2 and GFAP levels.

RESULTS

A total of 116 consecutive children were included, with the median age of 0.75 years (interquartile range: 0.42-8.00) and the median weight of 8.3 kg (5.8-20.0). Single-ventricle anatomy was present in 19 patients (16.4%). Deep hypothermic circulatory arrest (DHCA) was used in 14 patients (12.1%). On univariable analysis, nadir DO2 was significantly associated with GFAP values measured during rewarming on CPB (P = 0.005) and after CPB decannulation (P = 0.02). On multivariable analysis controlling for CPB time, DHCA and procedure risk category, a significant negative relationship remained between nadir DO2 and post-CPB GFAP (P = 0.03).

CONCLUSIONS

Lower nadir DO2 is associated with increased GFAP levels, suggesting that diminished DO2 during paediatric heart surgery may be contributing to neurological injury. The DO2-GFAP relationship may provide a useful measure for the implementation of neuroprotective strategies in paediatric heart surgery, including goal-directed perfusion.

Intracardiac Thrombosis and Acute Right Ventricular Failure Following Complex Reoperative Cardiac Surgery With Aprotinin and Deep Hypothermic Circulatory Arrest

Although coagulopathy and bleeding are common in the setting of cardiac surgery, a growing number of case reports in the literature suggest that hypercoagulability may also result in significant morbidity and mortality. We present a case of apparent hypercoagulability with formation of thrombus in the cardiac chambers following reoperative cardiac surgery using cardiopulmonary bypass, aprotinin, and deep hypothermic arrest. A review of those hypercoagulable disorders with reported impact on cardiac surgery and a discussion follow the case presentation.

Emergency Preservation and Resuscitation Trial: A Philosophical Justification for Non-Voluntary Enrollment

In a current clinical trial for Emergency Preservation and Resuscitation (EPR), Dr. Samuel Tisherman of the University of Maryland aims to induce therapeutic hypothermia in order to 'buy time' for operating on victims of severe exsanguination. While recent publicity has framed this controversial procedure as 'killing a patient to save his life', the US Army and Acute Care Research appear to support the study on the grounds that such patients already face low chances of survival. Given that enrollment in the trial must be non-voluntary, the study has received an exemption from federal standards for obtaining informed consent. How exactly, if at all, is non-voluntary enrollment morally justifiable? In this essay, I appeal to the notable work of Hans Jonas in an effort to defend the EPR trial's use of non-voluntary enrollment. It is often thought and, as I show, it may appear that Jonas has called for the end of experimental medical practice. Still, I derive from Jonas a principle of double-effect upon which physicians may be seen as morally permitted to pursue innovations in emergency medicine but only as a byproduct of pursuing therapeutic success. With this position, I argue that the EPR trial can be granted a stronger philosophical justification than simply waiving the requirement of obtaining informed consent. The double-effect justification would obtain, perhaps regardless of the success of such innovative procedures as therapeutic hypothermia.

[MODERN TECHNOLOGIES OF THE SAVING OF PATIENT'S BLOOD AND REDUCTION OF THE USE OF DONOR BLOOD DURING OPERATIONS ON THE ASCENDING AORTA AND AORTIC ARCH]

Questions of saving of the patient's blood and limitation of the use of donated blood in the aortic surgery remain relevant in contrast with interventions on the valves of the heart and coronary arteries. In this regard, the aim of the study was to develop and introduce ofcomplex of technologies for saving the patient's blood in order to minimize transfusion of donor blood components during operations on the ascending aorta and aortic arch under hypothermic arrest. The study included 37 patients operated on the ascending aorta and aortic arch under cardiopulmonary bypass (CPB) and hypothermic cardiac arrest (CA) in 2013-2014 (Group 1). 2nd group consisted of 65 patients who at the same time performed reconstructive surgery on the ascending aorta with CBP without stopping the blood circulation. The comparative aspect studied the following parameters: duration of the CBP, CA, temperature, volume of intraoperative and postoperative blood loss, frequency of use of donor blood components autoplasma, washed red blood cells, autologous blood, hemostatic agents, the frequency resternotomy, hematocrit dynamics, glucose, and blood lactate. Comparative studies have shown that the amount of intraoperative blood loss during operations on the aortic arch under the CA was 1294 ± 303 mL, 20% higher than the blood loss during operations on the ascending aorta without CA. Program of saving of the blood of patients with aortic disease included preoperative preparation of autoplasma in 60% of patients, intraoperative collection and laundering of autoerythrocytes in 40-70% of patients and autotransfusion modified method, the improvement of surgical and pharmacological hemostasis and monitoring. Design and implementation of these methods reduced the patients need for donor red blood cells (from 76 to 47%), fresh frozen plasma (from 65 to 35%) during the operation at the aortic arch and the ascending aorta and to completely avoid the use of donor blood in 25% of patients. Proof of the adequacy of the developed strategy of conservation and limitation of the patient's blood was allogeneic blood conservation targets hemoglobin, hematocrit levels and metabolism at the end of the operation.

Modified total arch replacement using a four-branched arch graft for acute type A aortic dissection with minimal brain and spinal cord ischemic time

AIM

This study aimed to evaluate the results of modified surgical strategies of total arch replacement using a four-branched arch graft, stented elephant trunk, and innovative organ protection method for acute type A aortic dissection.

METHODS

Between August 2011 and December 2011, 21 patients with acute type A aortic dissection underwent modified total arch replacement using the four-branched arch graft technique. All 21 patients had emergency surgery. Five patients had undergone previous aortic or cardiac surgery. The operations were stented elephant trunk implantation in 17 patients, ascending aorta replacement in 21 patients, coronary artery bypass grafting in four patients, Bentall operation in two patients, and aortic valve replacement in one patient. Twenty-one operations were performed under deep hypothermic extracorporeal circulation, modified selective cerebral perfusion, and end-organ and spinal cord protection for arch reconstruction.

RESULTS

There was two in-hospital deaths (9.5%). No persisting neurologic deficits or paraplegia occurred in 21 patients. Cardiopulmonary bypass time was 177.9±37.8 minutes. Myocardial ischemic time was 110.3±29.3 minutes. ICU time was 8.8±6.9 days and in-hospital duration was 28.7±13.7 days. Ventilation time varied from 9 hours to 21 days. A tracheotomy was necessary in four patients. Mean follow-up was 7.3±1.7 months and all patients are still alive.

CONCLUSION

Modified total arch replacement using a four-branched arch graft with stented elephant trunk and innovative organ protection is a useful and safe alternative technique for the treatment of acute type A aortic dissection and the results are encouraging.

Anticoagulation with bivalirudin during deep hypothermic circulatory arrest in a patient with heparin-induced thrombocytopenia

Heparin-induced thrombocytopenia is a well-recognized complication of anticoagulation with heparin. We present the case of a patient with recent heparin-induced thrombocytopenia who subsequently needed surgery on an emergency basis for acute type A aortic dissection. This article reports the successful use of bivalirudin, a direct thrombin inhibitor, as an alternative to heparin throughout cardiopulmonary bypass and deep hypothermic circulatory arrest. We contend that bivalirudin is a safe alternative to heparin when performing surgery for aortic dissection and should be considered as an option for use in patients who present with heparin-induced thrombocytopenia.

Huge ascending aorta and aortic arch aneurysm in ultra octogenarian

Giant ascending aorta aneurysms (AAA), which are larger than 10 cm, are rarely been reported (1-7). We hereby present the case of a giant AAA of about 11 cm in a very old women who was successfully operated on for ascending aorta and aortic arch replacement under deep hypothermic circulatory arrest.

[Anesthetic management of intraoperative aortic dissection during cardiovascular surgery]

Despite considerable advances in anesthesia technique, intraoperative aortic dissection remains a potentially lethal complication during on-pump cardiovascular surgery. Intraoperative dissection has been described worldwide, ranging between 0.06% and 0.24%. Here we present 8 patients who had intraoperative dissection during 10-year period with 6,266 on-pump cases (0.13%, 95% confidence interval 0.12% to 0.14%). In-hospital mortality rate of intraoperative dissection was 12.5% (1/8) at our institution, which was exceptionally lower than that reported previously (24% to 43%). Therefore, we also show our treatment strategy for intraoperative dissection with the related-literature review. The original surgical procedures were descending aortic replacement in 3 patients, valve replacement in 4 patients, and aortic-root replacement in 1 patient. Dissection occurred during aortic cannulation in 6 patients and during manipulation of aortic cross-clamping/de-clamping in 2 patients. Three patients had retrograde dissection extending and beyond the arch. Trans-esophageal echocardiography was useful to confirm dissection and ensure proper perfusion of the aortic-branches. Immediately after its diagnosis, all patients were managed with hypotensive strategy and subsequently underwent deep hypothermic circulatory arrest for prevention of dissection propagation. Among patients with intraoperative aortic dissection undergoing on-pump cardiovascular surgery, not only earlier diagnosis but proper anesthetic management may be crucial for the successful outcome.

Cerebral blood flow changes during rat cardiopulmonary bypass and deep hypothermic circulatory arrest model: a preliminary study

Cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) are important techniques often used in complex cardiac surgery for neonates and infants heart diseases. Cerebral blood flow (CBF) serves as an important physiological parameter and provides valuable hemodynamic information during the surgery. Laser speckle imaging (LSI), as an optical imaging technique, can provide full-field CBF information with a high spatiotemporal resolution. In this preliminary study, we acquired the real-time CBF images with a self-developed miniaturized head-mounted LSI system during the whole CPBillHCA rat model. Relative CBF velocity in veins and arteries in bilateral hemispheres dropped significantly during cooling period and reached to nearly zero during arrest period (n = 5). More interestingly, two rats showing more dramatic CBF variations in veins than in arteries during cooling period exhibited severe cerebral edema after surgery. The real-time full-field CBF imaging during the CPBillHCA surgery could add more insights into the operation and be utilized to study the surgical protocols with the ultimate goal ofreducing neurologic injury after surgery.

[Anesthetic management of Stanford type A aortic dissection operation]

OBJECTIVE

To explore the anesthetic management experiences of patients with Stanford A aortic dissection undergoing surgical treatment through moderate or deep hypothermia circulatory arrest (DHCA).

METHODS

From June 2008 to December 2011, a total of 77 patients undergoing surgical treatment of Stanford A aortic dissection was recruited.

RESULTS

Cardiopulmonary bypass (CPB) was established under general anesthesia in all patients. The procedures included moderate hypothermia (n = 51) and DHCA (n = 26). The total surgical duration was 152 - 600 (292 ± 91) min, CPB time 38 - 310 (128 ± 43) min and aortic cross-clamp time 31 - 169 (87 ± 26) min. The time of circulatory arrest under deep hypothermia was 20 - 113 (41 ± 19) min in 26 patients. Among 77 patients, there were 5 intraoperative and 7 postoperative fatalities. The remained 65 patients were discharged postoperatively and received a regular outpatient follow-up. None of them died or required reoperation.

CONCLUSION

Surgical treatment is appropriate and efficient for the patients with Stanford A aortic dissection. During surgery, the keys of preventing neurological complications are blood volume monitoring and blood protection.

[Anesthetic management of pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension--series of severe cases]

We report seven cases of anesthetic management for pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension (CTEPH) during past seven years in our hospital. All the patients were suffering from right heart failure and pulmonary hypertension, and the preoperative mean pulmonary artery pressure (mPAP) was 51.2 +/- 10.2 mmHg, and the pulmonary vascular resistance (PVR) was 894.2 +/- 207.7 dyne x sec(-1) x cm(-5). The surgical operation was performed using the deep hypothermia and circulatory arrest technique. The postoperative mPAP and PVR decreased to 15.5 +/- 7.5 mmHg and 181.6 +/- 84 dyne x sec(-1) x cm(-5), respectively. The patients' symptoms such as shortness of breath, and dyspnea improved and they were discharged without any serious complications.

[Infected implantable cardioverter-defibrillator lead extraction under deep hypothermic circulatory arrest; report of a case]

We performed infected implantable cardioverter-defibrillator lead extraction under deep hypothermic circulatory arrest in a 58-year-old man. Venogram during the implantation of the lead had revealed complete obstruction of the innominate vein. Preoperative trans-esophageal ecocardiogram revealed intracardiac vegetation with a diameter of 20×13 mm. Because of advanced adhesion and large vegetation, we performed lead extraction under cardiopulmonary bypass. The leads were adherent to the wall of the superior vena cava( SVC) and the innominate vein and could not be extracted. So we converted to deep hypothermic circulatory arrest. We performed venotomy in the SVC and the innominate vein to achieve complete visualization. The leads were extracted under direct vision. Postoperative course was uneventful without recurrence. Extraction of implantable devices is highly recommended when infection occurs. When adhesion of the lead is suspected, safe extraction can be performed by venotomy of the innominate vein under deep hypothermic circulatory arrest.

Concomitant aortic valve and ascending aorta replacement with moderate hypothermic circulatory arrest to treat an aortic bicuspid valve with post-stenotic dilatation

We recommend concomitant surgery for aortic valve replacement (AVR) and ascending aortic replacement using moderate hypothermic circulatory arrest (CA) for post-stenotic dilatation complicated by an aortic bicuspid valve. Cardiopulmonary bypass (CPB) was established from the right atrium to the dilated ascending aorta. As soon as the rectal temperature decreased to 28 °C, CA was commenced and the open distal anastomosis of a polyester prosthesis, without any cerebral perfusion, was completed. AVR was then carried out during rapid re-warming with CPB using a side arm of the prosthesis. This procedure exhibited safe and satisfactory results. There are many benefits of carrying out the procedure in this way; it avoids the requirement for cannulation to a calcified aortic arch, provides a good operative field, for an easier distal anastomosis and suturing at the valve site, and reduces the risk of further dilatation or dissection of the residual ascending aorta in the later phase.

Antegrade versus retrograde cerebral protection in repair of acute ascending aortic dissection

The objective of this study was to compare retrograde with antegrade cerebral protection during acute aortic dissection repair using cerebral oximetry measurements. Fifty consecutive acute ascending aortic dissection repairs were analyzed. Cerebral oximetry data were collected for 41 of 50. Eight patients who had antegrade cerebral protection alone and 29 of 41 had retrograde cerebral protection alone. The per cent change in cerebral oximetry values during deep hypothermic circulatory arrest from baseline and from prearrest values was compared for the two groups using Student t test. The per cent change from baseline for the antegrade patients was: right 13.8 per cent and left -2.5 per cent; the per cent change from baseline for retrograde patients was: right 0.8 per cent and left 0.2 per cent (P values 0.216 and 0.725, respectively). The per cent change from the prearrest value for the antegrade patients was: right -12 per cent and left -15 per cent; the per cent change from prearrest for retrograde patients was: right -15 per cent and left -16 per cent (P values 0.514 and 0.956, respectively). No compelling evidence for an advantage to either antegrade or retrograde cerebral perfusion was detected. Further study with a focus on neurologic outcomes is warranted.

A time bomb in the thorax: the giant ascending aortic aneurysm: case report

We report the case of a 82-year-old woman, asymptomatic, subject to chest computed tomography for trauma. Then the patient underwent surgery. Before sternotomy, femoro-femoral bypass was starter in order to decompress the aneurysm; using deep hypothermia and circulatory arrest, ascending aorta and hemiarch replacement were performed with a Dacron graft. Post-operative course was uneventful.

Technical description of the use of selective perfusion techniques during the Norwood procedure for hypoplastic left heart syndrome

Since the introduction of the Norwood procedure for surgical palliation of hypoplastic left heart syndrome in 1983, refinements have been made to the original procedure to improve patient outcomes while still accomplishing the original goals of the procedure. One of these refinements has been the introduction of regional selective perfusion to limit the duration of circulatory arrest times and optimize the regional flow distribution. In this paper we describe our technique for performing selective cerebral and lower body perfusion during the Norwood procedure.

[Surgical treatment of DeBakey type II aortic dissection combined with true aneurysm in the distal aortic arch: a case report]

DeBakey type II aortic dissection combined with true aneurysm in the distal aortic arch is a very rare condition, and due to the complicated pathology, its surgical intervention can be difficult and risky. We report a case with this pathology in a 23-year-old man, who received a previous open heart surgery for ventricular septal defect at the age of 6 years. Aortic valve, ascending aorta and total aortic arch replacements were performed. Cardiopulmonary bypass (CPB) including deep hypothermic circulatory arrest with selective antegrade cerebral perfusion was used. No postoperative complications occurred, and the follow-up examination at 6 months after the operation showed good therapeutic results.

[Surgical management of a complex intracranial dural ateriovenous fistula with deep hypothermia circulatory arrest: a case report and literature review]

Hypothermia and cardiopulmonary bypass has been used for difficult lesions of the brain such as giant aneurysms. We reported a case of complex intracranial dural arteriovenous fistula (DAVF) undergoing surgery with deep hypothermic circulatory arrest (DHCA). The advantages and disadvantages of this operation were discussed. This is the first report describing the use of DHCA in the surgical management of complex intracranial DAVF. We also reviewed the literature documenting the treatment of DAVF and the history of deep hypothermia and circulatory arrest in cerebrovascular surgery.

[Perioperative monitoring and control of hyperglycemia during deep hypothermic circulatory arrest]

OBJECTIVE

To observe the trend of change in perioperative blood glucose level in patients undergoing deep hypothermic circulatory arrest (DHCA), in order to evaluate the influencing factors of inciting hyperglycemia and the clinical effects of insulin control.

METHODS

In the Department of Cardiothoracic Surgery of Changhai Hospital, 176 patients underwent aortic operation under DHCA from January 2000 to January 2010. Blood glucose, arterial blood gas and lactate levels were determined at four time points, including pre-cardiopulmonary bypass (CPB), pre-DHCA, post-DHCA, and at admission to intensive care unit (ICU). Hyperglycemia after surgery was controlled at the level of 6-8 mmol/L by intermittent subcutaneous injection or intravenous micropump injection of insulin. At the same time, the cumulative amount of insulin within 24 hours after surgery was recorded.

RESULTS

The blood glucose (mmol/L) level at pre-DHCA time point was significantly higher than that of pre-CPB (9.62 ± 1.79 vs. 5.04 ± 1.401,P<0.05), and the blood glucose level was further elevated at the time point of post-DHCA (14.91 ± 2.36,P<0.01) and in-ICU (15.32 ± 2.47) compared with that of pre-CPB (P<0.01). The level of blood glucose elevation was positively correlated with blood lactate level. One hundred and thirty-four patients (76.1%) insulin was given with intravenous micropump due to poor effect of intermittent subcutaneous injection of insulin in controlling blood glucose. Among whom 30 patients (17.0%) developed the phenomenon of insulin resistance. Perioperative hyperglycemia during DHCA was associated with old age (≥ 50 years old), primary hypertension, serious aortic valve disease, diabetes or coronary heart disease, emergency operation, CPB time ≥ 3 hours and DHCA time ≥ 45 minutes. The cumulative amount of insulin within 24 hours after surgery was increased significantly. The results of blood glucose (mmol/L) in-ICU were as follows : age ≥ 50 years old or < 50 years old (18.66 ± 2.52 vs. 12.90 ± 2.27); hypertension with and without (18.98 ± 2.55 vs. 12.31 ± 2.34); serious aortic valve disease with and without (19.59 ± 2.95 vs. 12.13 ± 2.23); diabetes with and without (20.62 ± 1.76 vs. 11.75 ± 1.11); coronary heart disease with and without (19.77 ± 2.98 vs. 12.01 ± 2.02); emergency operation with and without (19.78 ± 1.97 vs. 12.23 ± 1.38); CPB time ≥ 3 hours or < 3 hours (19.86 ± 1.89 vs. 11.70 ± 1.15); DHCA time ≥ 45 minutes or < 45 minutes (19.92 ± 1.88 vs. 11.64 ± 1.12), and all of them should statistical difference (all P < 0.05). The cumulative amount of insulin (U) within 24 hours after surgery was as follows: age ≥ 50 years old or < 50 years old (169.5 ± 56.6 vs. 110.2 ± 38.5); hypertension with and without (171.6 ± 64.0 vs. 104.8 ± 34.3); aortic valve disease with and without (171.4 ± 36.8 vs. 109.4 ± 27.6); diabetes with and without (202.5 ± 46.7 vs. 100.4 ± 31.5); coronary heart disease with and without (178.5 ± 38.6 vs. 104.6 ± 26.4 ); emergency operation with and without (178.3 ± 35.7 vs. 102.7 ± 26.8); CPB time ≥ 3 hours or < 3 hours (168.6 ± 37.2 vs. 107.3 ± 27.5); DHCA time ≥ 45 minutes or < 45 minutes (172.5 ± 36.1 vs. 105.4 ± 28.7), and all of them showed significant statistical difference (all P < 0.05). and all of them showed significant statistical difference (all P < 0.05).

CONCLUSION

DHCA may cause significant increase in perioperative blood glucose and lactate, and even may lead to insulin resistance. Patients often require continuous intravenous administration of large doses of insulin. Perioperative hyperglycemia during DHCA is related to many factors, which should be considered in control of blood glucose.

Ruptured thoracic descending aortic aneurysm coexisting with DeBakey type IIIb aortic dissection

We have encountered a rare case of ruptured true thoracic aortic aneurysm coexisting with DeBakey type IIIb aortic dissection. The patient was a 67-year-old woman who had a past history of hypertension and cerebral infarction. She experienced DeBakey type IIIb acute aortic dissection, and initially conservative medical treatment was carried out. However, the patient suddenly went into shock, and emergency contrast-enhanced computed tomography revealed the presence of a ruptured true thoracic aortic aneurysm coexisting with the type IIIb dissection. Replacement of the descending aorta was performed through a left thoracotomy using circulatory arrest and deep hypothermia. The rupture site and intimal tear were located in the middle of the aneurysm. Open proximal and distal anastomoses were carried out using a 22 × 10 mm gelatin-covered Dacron graft. The patient was discharged from our hospital uneventfully on the 33rd postoperative day.

[Ultrastructure of coronary microvessels in conditions of heart reperfusion following prolonged ischemia while applying various methods of artificial hypothermia]

It has been found out that in children with Roger's disease corrected in the conditions of two fundamentally different procedures of anesthetic management, myocardial reperfusion after cardiac arrest under artificial hypothermic circulation is accompanied by obstruction of more than 30% of coronary bed microvessels with hydropic endothelial cells or their cystiform fragments. The content of necrotic cells increases, while the "working" cells demonstrate a decrease in myocropinocytotic transport characteristics. Circulatory arrest under perfusionless hypothermia and immersion reperfusion do not result in a dramatic change of general morphology of microvessels as compared to the control group, while a heterogenic response of the structures responsible for transendothelial transfer of macromolecules provides the basis for recovery of the endothelium structure and function, as a patient's temperature reaches a standard value.

Improved cerebral recovery from hypothermic circulatory arrest after remote ischemic preconditioning

BACKGROUND

Remote ischemic preconditioning is a novel method of reducing ischemia-reperfusion injury in which a transient ischemic period of the limb provides systemic protection against a prolonged ischemic insult. This method of preconditioning has shown some potential in ameliorating ischemia-related injury in various organs and experimental settings. We hypothesized that remote ischemic preconditioning might also improve the recovery from hypothermic circulatory arrest (HCA).

METHODS

Twenty-four juvenile pigs underwent 60 minutes of HCA at 18 degrees C with either transient right hind leg ischemic preconditioning or no ischemic preconditioning. Preconditioning was induced by four cycles of 5-minute ischemia periods with three 5-minute reperfusion periods in between. Microdialysis and electroencephalography (EEG) data were recorded to detect any possible changes during the recovery phase.

RESULTS

The EEG data showed that the remote ischemic preconditioning group had significantly better EEG recovery time and a lower burst suppression ratio throughout the follow-up period. Cerebral extracellular glucose and glycerol content rose significantly immediately after HCA in the control group compared with the remote ischemic preconditioning group, and significantly higher lactate concentrations were measured in the control group at 5 and 6 hours after reperfusion, indicating a difference in cerebral metabolism.

CONCLUSIONS

Our data imply that remote ischemic preconditioning improves the recovery from HCA. It provides a faster recovery of cortical neuronal activity and protection against potential oxygen radical-mediated ischemia damage during and after HCA. In addition, it seems to protect from a late phase lactate and pyruvate burst, mitigating possible damage from an anaerobic metabolism phase.

[The relative risk factors analysis of hepatic dysfunction following aortic dissection repair]

OBJECTIVE

To analyze the risk factors of hepatic dysfunction following Stanford A and stanford B aortic dissection repair with deep hypothermic circulatory arrest (DHCA).

METHODS

Between January 2006 and June 2008, 208 patients [156 male and 52 female, mean aged (45 ± 11) years] underwent open repairs of aortic dissection with DHCA. Indications for surgical intervention were type A aortic dissection in 181 patients and type B in 27 patients. Acute aortic dissection occurred on 121 patients, chronic aortic dissection occurred on 87 patients. Complications included hypertension, diabetes, cardiac dysfunction, renal dysfunction, and hepatic dysfunction. Twenty-one patients had previous aortic surgery. Data were gathered for multiple preoperative and intraoperative factors including age, gender, diagnosis, aortic dissection type, preoperative ejection fraction, aortic surgery history, surgical intervention type, cardiopulmonary bypass (CPB) time, aortic cross-clamp time, blood transfusion volume (PRBC). Serum glutamic-pyruvic transaminase (GPT), 1-lactate dehydrogenase (LDH) and total bilirubin (TBIL) were assayed before and after operation, as well as 12 h, 1 d, 3 d, 5 d, 7 d. These valuables were recorded and described statistically. All the factors were evaluated by means of univariate and multivariate Logistic analysis to identify relative risk factors of hepatic dysfunction.

RESULTS

The CPB time and aortic cross-clamp time were (189 ± 48) min and (93 ± 41) min, respectively. Hepatic dysfunction occurred in 18 (8.7%) patients. Serum GPT and serum LDH elevated significantly within 24 h after aortic surgery, and then went down gradually. Postoperative serum TBIL were much higher than preoperative level on the first day and there was no significant reduction during the following seven days. Preoperative serum creatinine > 133 µmol/L (P < 0.01), preoperative GPT > 40 U/L (P < 0.01), acute aortic dissection (P < 0.05), CPB time > 180 min (P < 0.05), aortic cross-clamp time > 100 min (P = 0.035), PRBC > 10 unit (P < 0.01) were the risk factors for hepatic dysfunction. Furthermore preoperative GPT > 40 U/L (P < 0.01) and PRBC > 10 unit (P < 0.01) were independent determinants for hepatic dysfunction.

CONCLUSIONS

Multiple risk factors impact the onset of postoperative hepatic dysfunction. Rather, a combination of factors, especially preoperative hepatic injury, massive blood transfusion produced the highest odds of deficit.

Perioperative stroke in infants undergoing open heart operations for congenital heart disease

BACKGROUND

The prevalence of perioperative stroke in infants undergoing operations for congenital heart disease has not been well described. The objectives of this study were to determine the prevalence of stroke as assessed by postoperative brain magnetic resonance imaging (MRI), characterize the neuroanatomic features of focal ischemic injury, and identify risk factors for its development.

METHODS

Brain MRI was performed in 122 infants 3 to 14 days after cardiac operation with cardiopulmonary bypass, with or without deep hypothermic circulatory arrest. Preoperative, intraoperative, and postoperative data were collected. Risk factors were tested by logistic regression for univariate and multivariate associations with stroke.

RESULTS

Stroke was identified in 12 of 122 patients (10%). Strokes were preoperative in 6 patients and possibly intraoperative or postoperative in the other 6 patients, and were clinically silent except in 1 patient who had clinical seizures. Arterial-occlusive and watershed infarcts were identified with equal distribution in both hemispheres. Multivariate analysis identified lower birth weight, preoperative intubation, lower intraoperative hematocrit, and higher blood pressure at admission to the cardiac intensive care unit postoperatively as significant factors associated with stroke. Prematurity, younger age at operation, duration of cardiopulmonary bypass, and use of deep hypothermic circulatory arrest were not significantly associated with stroke.

CONCLUSIONS

The prevalence of stroke in infants undergoing operations for congenital heart disease was 10%, half of which occurred preoperatively. Most were clinically silent and undetected without neuroimaging. Mechanisms included thromboembolism and hypoperfusion, with patient-specific, procedure-specific, and postoperative contributions to increased risk.