Aortic arch replacement with a beating heart: a simple method using continuous 3-way perfusion.

We describe a simplified 3-way perfusion strategy that could be used in complex aortic procedures, which ensures continuous end-organ perfusion and minimizes the potential risks of cardiac, cerebral and peripheral ischaemic complications.

The effect of retrograde autologous priming on intraoperative blood product transfusion in coronary artery bypass grafting.

INTRODUCTION: Retrograde autologous priming (RAP) of the cardiopulmonary bypass (CPB) circuit could reduce the degree of haemodilution associated with priming with acellular solutions. However, there is no strong evidence to prove that the practice of RAP reduced intraoperative packed red cell (PRC) or blood product transfusion. OBJECTIVE: To evaluate the effect of RAP on intraoperative PRC usage in coronary artery bypass grafting (CABG). METHODS: This study is a prospective, observational study on patients who underwent first-time, isolated CABG using CPB between April 2012 and July 2012. Two groups of patients were identified: 1. Non-RAP group (n=128) and 2. RAP group (n=73). The primary outcome for the study was the amount of PRC and blood product usage between the induction of anaesthesia and the cessation of CPB. RESULTS: Use of PRC and blood products in the operating room was comparable in both groups. Univariate logistic regression showed that RAP was not an independent predictor of PRC or blood product transfusion (p=0.43). Multivariate logistic regression showed that CPB time, preoperative haemoglobin (Hb) levels and creatinine clearance were independent predictors of blood product transfusion. CONCLUSION: Practising RAP with mean volumes of 300 ml does not necessarily reduce PRC and other blood product transfusion requirements during CABG. In our practice, RAP was performed, aiming at displacing CPB circuit prime volume with which the perfusionist felt comfortable and dictated by haemodynamic parameters prior to commencing CPB. We presume this is the case in many units around the world. This practice, in our opinion, is not enough to achieve the benefits of RAP, if any, in the form of a reduction of packed red cell transfusion requirements. The true advantages of RAP in cardiac surgery need to be studied in a prospective, randomized, controlled trial.

Ex vivo perfusion of the swine heart as a method for pre-transplant assessment.

We describe a cost-effective, reproducible circuit in a porcine, ex vivo, continuous warm-blood, bi-ventricular, working heart model that has future possibilities for pre-transplant assessment of marginal hearts donated from brain stem dead donors and hearts donated after circulatory determination of death (DCDD). In five consecutive experiments over five days, pressure volume loops were performed. During working mode, the left ventricular end systolic pressure volume relationship (LV ESPVR) was 23.1±11.1 mmHg/ml and the LV preload recruitable stroke work (PRSW) was 67.8±7.2. (Standard PVAN analysis software) (Millar Instruments, Houston, TX, USA) All five hearts were perfused for 219±64 minutes and regained normal cardiac function on the perfusion system.They displayed a significant upward and leftward shift of the end systolic pressure volume relationship, a significant increase in preload recruitable stroke work and minimal stiffness. These hearts could potentially be considered for transplantation. The circuit was effective during reperfusion and working modes whilst proving to be successful in maintaining cardiac function in excess of four hours. Using an autologous prime of approximately 20% haematocrit (Hct), electrolytes and blood gases were easy to control within this period using standard perfusion techniques.

Coagulopathy associated with massive cell salvage transfusion following aortic surgery.

Cell saver blood is used within the peri-operative setting of cardiothoracic surgery to reduce the need for transfusion of allogenic blood products. Several meta-analyses have proven a significant decrease in allogenic transfusion with the use of cell salvage techniques. Washing of red cells by the cell saver and subsequent transfusion of suspended red cells can occasionally cause coagulopathy, particularly when using high concentration heparin saline to wash the spilled blood. We present the case of a 74-year-old female who underwent complicated aortic surgery and was transfused large volumes of cell-saved blood due to post-operative bleeding, which subsequently led to coagulopathy.

The effect of oxygenator choice on hypotension during cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) exposes blood to artificial surfaces, which induces a systemic inflammatory activation.This may contribute to hypotension during CPB. A perceived difference between two membrane oxygenators was noted. Data were collected on 222 consecutive patients; four were excluded from the analysis due to having emergency operations. One hundred and twelve (51%) patients received the Apex oxygenator whilst 106 (49%) received the Quadrox. There was no difference between the two groups in the primary outcome; 90/112 patients (80%) in the Apex group and 77/106 (73%) in the Quadrox group (p=0.18, OR: 0.65; 95% CI: 0.34, 1.22) received meteraminol due to marked hypotension during CPB. There was also no difference in the secondary outcomes, length of stay in ICU (22.8 versus 22.7 hours, (OR 0.79, 95% CI: 0.42, 1.48, p=0.16) and length of stay in hospital (8.5 days versus 8.0 days (OR: 0.83, 95% CI: 0.48, 1.45; p=0.52). The choice of oxygenator between the Apex and Quadrox does not have an effect on hypotension in cardiac surgery.

Cardiopulmonary bypass and deep hypothermic circulatory arrest in a massively obese patient.

As a consequence of the rising global prevalence and magnitude of obesity, a greater proportion of patients presenting for cardiac surgery is morbidly obese. Being overweight (body mass index; BMI 25-29.9 kg/m(2)) or obese (BMI 30-35 kg/m(2)) appears to confer some survival benefit following cardiac surgery. By contrast, morbid obesity (BMI >40 kg/m(2)) is associated with an increased likelihood of postoperative complications and prolonged intensive care unit and hospital length of stay. The physical difficulties encountered when managing this group of patients is exemplified by those undergoing complex, multiple procedures requiring prolonged cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA). We present the successful management of a massively obese 19-year-old male (BMI 45 kg/m(2)) with Marfan's syndrome who required aortic root and arch replacement under DHCA. The selection of extracorporeal circuit components to accommodate a large circulating volume and permit high CPB flow rates (>9 l/min) is discussed.

Tactile recognition in infantile nephropathic cystinosis.

Previous studies have demonstrated that individuals with cystinosis, an inherited metabolic disorder, have difficulty processing visual information, and may be selectively impaired in the ability to mentally rotate figures, despite having normal IQs and normal primary sensory function. In our novel task-the 'Black Box'-subjects identified objects solely by feeling the contours. Twenty-three subjects with cystinosis, aged 4 to 34 years, were individually matched with controls on age, sex, handedness, and test form. Subjects with cystinosis performed significantly worse in identifying objects than did controls. In addition, when only subjects over 7 years of age were included, those with cystinosis took significantly longer to correctly identify objects than did controls. Our findings suggest that individuals with cystinosis have difficulty with tactile recognition of common objects. These results support the hypothesis that a genetic disorder may have specific behavioral correlates.

Atypical fibrous histiocytoma with myxoid stroma: a rare lesion arising from dura mater of the brain.

Intracranial fibrohistiocytic tumors are rare. This report is concerned with a 24-year-old white male who had an 8 month history of intermittent visual disturbance. Craniotomy revealed a large, completely intradural lesion on the floor of the left anterior cranial fossa without involvement of the leptomeninges or brain parenchyma. Gross and microscopic examination revealed that the fibrogenic portion of the tumor was composed of spindle shaped neoplastic cells arranged in storiform pattern, a hallmark of fibrohistiocytic tumor. In contrast to three previously reported cases of "fibrous xanthomas" involving the leptomeninges and superficial cortex of the brain, the present lesion is clearly originated from mesenchymal stem cell of the dura. The other distinct gross and microscopic feature was the presence of myxoid component which constituted about 40% of the entire lesion. The myxoid component had not been observed in previous 5 reported cases of intracranial fibrohistiocytic lesions. Since there was cellular pleomorphism with extremely rare mitosis, it was felt that the lesion be best designated as atypical fibrous histiocytoma with myxoid stroma.