T.K. Susheel Kumar

Extracorporeal membrane oxygenation in postcardiotomy patients: factors influencing outcome.

OBJECTIVE Our objective was to assess the morbidity and mortality in children requiring extracorporeal membrane oxygenator support after cardiac surgery and to determine factors influencing outcome. METHODS Between January 2003 and June 2008, 58 patients required extracorporeal membrane oxygenator support after cardiac surgery. A retrospective study was performed and factors influencing outcome were determined by logistic regression modeling with the probability of outcome based on a combination of multivariate predictors. RESULTS Median age and weight were 12 days and 3.3 kg, respectively. Thirty-one patients had single ventricle repair and 27 had biventricular repair. Median duration of support with the oxygenator was 6 days. Thirty-nine (67%) patients were successfully weaned off the support, but only 24 (41%) survived to hospital discharge. Chief complications were renal failure (31%), neurologic complications (29%), and sepsis (16%). Multivariable logistic regression analysis identified 10 days or more of extracorporeal membrane oxygenation (odds ratio = 6.1), urine output less than 2 mL x kg(-1) x h(-1) in first 24 hours (odds ratio = 15), renal failure (odds ratio = 9.4), and pH less than 7.35 after 24 hours of extracorporeal membrane oxygenation (odds ratio = 82) as significant independent factors associated with failure to wean off extracorporeal membrane oxygenation. Factors associated with failure of hospital discharge despite successful decannulation were as follows: extracorporeal membrane oxygenator support time of 10 days or more, red blood cell transfusion of greater than 1000 mL/kg during the entire period of oxygenator support, and sepsis. Patients with single ventricle repair were at higher risk of hospital mortality. CONCLUSION Longer duration of extracorporeal membrane oxygenator support, low pH and urine output in the first 24 hours, and renal failure are significant factors associated with mortality during extracorporeal membrane oxygenator support. Exposure to high amounts of blood transfusion during extracorporeal oxygenation, extended extracorporeal membrane oxygenator support, and sepsis increase risk of death after successful decannulation.

Hypothermic Circulatory Arrest Increases Permeability of the Blood Brain Barrier in Watershed Areas

BACKGROUND The integrity of the blood brain barrier (BBB) after cardiopulmonary bypass (CPB) with hypothermic circulatory arrest (HCA) is controversial in children. We tested the hypothesis that the BBB is disrupted by HCA. METHODS Forty-one piglets (mean weight 11 kg) were randomly allocated to acute and survival experiments. Five groups (25 piglets, 5 per group) underwent acute studies: anesthesia alone (control); CPB at 37°C with full-flow (FF); CPB at 25°C with very low flow (LF); HCA at 15°C, and HCA at 25°C. Two groups (16 piglets, 8 per group) underwent survival studies: CPB at 25°C with LF and HCA. In the acute studies, Evans blue dye (EBD) extravasation through the BBB into the brain was measured using two methods: EBD absorbance of homogenized brain, and immunohistochemical localization of EBD-linked albumin for cortex, caudate nucleus, thalamus, hippocampus, and cerebellum. In the survival studies, cerebral histology was assessed with hematoxylin-eosin stain after sacrifice at 4 days after surgery. RESULTS The BBB disruption was clearly observed around watershed areas for 25°C HCA compared with other conditions. Microscopic data showed that leakage of EBD in 25°C HCA was more severe than control in all brain areas (p < 0.05), and EBD and albumin were colocalizing. Histologic damage scores were significantly higher in watershed areas with 25°C HCA. CONCLUSIONS The BBB was impaired around watershed areas by 25°C HCA for 1 hour according to both macroscopic and microscopic data. An increase in permeability of the BBB may be both a sign and a mechanism of brain damage.

Superior Vena Cava Reconstruction for Treatment of Chylothorax Resulting From Thrombosis of Superior Vena Cava in Young Infants

BACKGROUND Thrombosis and occlusion of the superior vena cava (SVC) can cause massive chylothorax resulting in significant morbidity and mortality among young infants. Medical therapy is often unsuccessful. We report a new surgical technique that entails open thrombectomy and reconstruction of the SVC and innominate vein to treat this condition. METHODS The charts of 4 consecutive infants with chylothoraces refractory to conservative management were reviewed. The operations were performed on cardiopulmonary bypass without myocardial arrest. The SVC and innominate veins were incised open, and thrombectomy was performed. This was followed by homograft patch reconstruction of both the veins. RESULTS The infants were aged between 5 weeks to 4 months and had an average weight of 4 kg. All of them had hypoalbuminemia and evidence of hypercoagulable state. After surgical intervention, 3 had complete relief of SVC obstruction. Two of the 3 patients had complete resolution of chylous effusion, and the third patient had a significant decrease in chest tube drainage (70%) by the end of 1 week. The fourth patient had recurrence of high drainage after an initial improvement, and a subsequent angiogram demonstrated stenosis of the SVC without thrombosis. The chest tube drainage finally resolved after balloon angioplasty. CONCLUSIONS Thrombotic occlusion of the SVC can result in chylothorax that is often not amenable to medical therapy. This is associated with significant loss of proteins and hypercoagulable state. A complete surgical relief of SVC obstruction by open thrombectomy and venoplasty can result in dramatic decrease in chylous output.

Management of massive diffuse alveolar hemorrhage in a child with systemic lupus erythematosus

Diffuse alveolar hemorrhage (DAH) from systemic lupus erythematosus (SLE) is a rare but potentially life-threatening condition. We report the case of a 14-year-old female with SLE who developed hypoxia and shock secondary to severe alveolar hemorrhage. She was successfully managed by placement on extracorporeal membrane oxygenation (ECMO) followed by emergent pulmonary lobectomy and medical treatment including high-dose methylprednisolone, cyclophosphamide, intravenous immunoglobulin, and plasmapheresis.

Anomalous left coronary artery from the right pulmonary artery with aortic fusion.

CLINICAL SUMMARY A 3-month-old male infant was referred for elective repair of tetralogy of Fallot (TOF) with pulmonary stenosis. Echocardiography was consistent with a clinical picture of a ‘‘pink’’ TOF with normal coronaries. A total subannular repair of TOF with pulmonary stenosis was performed on cardiopulmonary bypass. During weaning, high left atrial pressures were noted with depressed left ventricular function. A transesophageal echocardiogram demonstrated satisfactory anatomic repair. Coronary anatomy was specifically examined. The left coronary artery appeared to originate from the left coronary sinus by both echocardiography and direct inspection. The patient was placed on extracorporeal membrane oxygenation (ECMO). Catheterization on ECMO the next day demonstrated an anomalous left main coronary artery (LMCA) arising from the RPA (Figure 1). At reoperation, careful dissection of the LMCA confirmed its origin from the RPA very close to the aorta. The ostium of the LMCAwas excised as a button, but the vessel 3 or 4 mm distally could not be separated from the aortic wall to which it was fused. No intramural segment could be detected through an aortic incision and by probing the coronary artery. The short length of the coronary artery between the RPA and the point of fusion to the aorta did not allow direct transfer of the coronary button without risk of kinking. Thus, it was sutured to the lateral edge of an opening made in the ascending aorta with pericardium used to roof the opening (Figure 1). A femoral vein homograft segment was interposed between the distal pulmonary

The second assistant in cardiac surgery: The challenges and answers

All cardiac surgeons begin their careers as second assistants in the operating room. Superfluous as this statement may appear, there is little mention in the surgical literature of the challenges of being a second assistant. This subject may appear trivial to those no longer in the role, but it is worth remembering that this is not only the earliest stage in a surgeon’s career, but also the most impressionable. Surprisingly little has been written about the demands of this role. Much has been written about the qualities a surgeon should possess, but little mention is made of the specific challenges faced in the earliest part of his or her career. In his book De re medicina, one of the first books to be published in the history of medicine, Aurelius Cornelius Celsus, a great authority on the subject, vividly described the qualities a surgeon should possess. He mentioned that a surgeon should have strong and steady hands, a sharp vision, and an undaunted spirit. Thomas Vicary, a sixteenth century surgeon, described what he considered the four most important qualities of a surgeon: the surgeon should be learned, expert, ingenious, and well mannered. Much later, William Halsted, pioneer of modern surgical training, stressed the need for a proper system to produce competent surgeons. His work has been followed by tons of material by different authors, all devoted to the description of the surgeon. However, all these authors allude primarily to the role of the primary surgeon, although there are occasional references to the first assistant. One cannot avoid the feeling that the second assistant has been ignored all along. The Royal Australasian College of Surgeons recently published a guide book called Surgical Competence and Performance, which provides a framework for assessing surgeons. Some of the markers in this guide have been borrowed from the NOTSS (Non Technical Skills for Surgeons) program of the Royal College of Surgeons, Edinburgh. Although the guide stresses the importance of teamwork in the operating room, the specific issues of second assistants have not been

Femoral vein homograft as Sano shunt results in improved pulmonary artery growth after Norwood operation

OBJECTIVE To evaluate differences in interstage growth of pulmonary arteries between use of polytetrafluoroethylene and femoral vein homograft as Sano shunt during stage-I Norwood palliation. METHODS A retrospective review of all patients who survived to the second stage following Norwood-Sano operation at two institutions was performed. Either polytetrafluoroethylene or the valved segment of femoral vein homograft was used for construction of the Sano shunt. The size of pulmonary arteries was compared at pre-Glenn catheterisation. RESULTS A total of 48 neonates with the diagnosis of hypoplastic left heart syndrome or its variants comprised the study population. Femoral vein homograft of 5-6 mm diameter was used in 14 and polytetrafluoroethylene graft of 5 mm was used in 34 patients. The two groups were comparable in terms of preoperative demographics and age at time of pre-Glenn catheterisation (3.9±0.7 versus 3.4±0.8 months, p=0.06). Patients who received femoral vein homograft demonstrated a significantly higher pre-Glenn Nakata index [264 (130-460) versus 165 (108-234) mm2/m2, p=0.004]. The individual branch pulmonary arteries were significantly larger in the femoral vein group (right, 7.8±3.6 versus 5.0±1.2, p=0.014; left, 7.2±2.1 versus 5.6±1.9, p=0.02). There were no differences in cardiac index, Qp:Qs, ventricular end-diastolic pressure or systemic oxygen saturations. CONCLUSIONS Utilisation of a valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit during Norwood-Sano operation confers better interstage growth of the pulmonary arteries. Further studies are needed to evaluate the impact of femoral vein homograft on single ventricle function.

Risks of extracorporeal membrane oxygenation in patients with coronary artery anomalies.

Extracorporeal membrane oxygenation is widely used to support and rest the heart before or following repair of congenital cardiac lesions in children. The beneficial effects of extracorporeal membrane oxygenation for the failing myocardium are undisputed. It is often an automatic choice whenever the heart seems incapable of supporting the circulation. However, its use may prove detrimental in patients with coronary anomalies, as illustrated by the case reports presented here.

Improved Outcomes in Management of Hypoplastic Left Heart Syndrome Associated With Congenital Diaphragmatic Hernia: an Algorithmic Approach

Hypoplastic left heart syndrome (HLHS) is the second most common congenital heart disease associated with congenital diaphragmatic hernia (CDH). The reported survival rate of neonates with CDH and HLHS is only 1%-5%. We review our experience with CDH and HLHS and compare our outcomes with published literature. Retrospective review of all neonates with CDH and HLHS at our institution over a 10-year period was performed. The morphology of cardiac and diaphragm defects, clinical course, treatment strategies, and outcomes were reviewed, and an algorithmic approach was proposed. Five patients with CDH and HLHS were treated between 2006 and 2016. All had mitral stenosis with aortic stenosis. Four patients had a left-sided Bochdalek diaphragmatic hernia and 1 patient had a large bilateral Morgagni hernia. Two (2/4) of the Bochdalek hernias were associated with significant pulmonary hypoplasia and required patch closure of the CDH; both were palliated with percutaneous ductal stents and both died. Three patients underwent primary Norwood operation followed by repair of less severe CDH defect. All 3 patients are currently well and have survived bidirectional Glenn anastomosis; one patient is well after Fontan operation. Successful palliation of neonates with HLHS and associated CDH is possible in the current era. Outcome is determined primarily by the severity of the CDH and the degree of associated pulmonary hypoplasia. An algorithmic team approach is helpful in management of this difficult group of patients.

Diaphragmatic fenestration for refractory chylothorax after congenital cardiac surgery in infants

Objective: Medically refractory chylous pleural effusion after congenital heart surgery is associated with significant morbidity and mortality, especially in infants. We reviewed our experience with diaphragmatic fenestration procedure in this group of patients. Methods: A retrospective chart review of all patients who had diaphragmatic fenestrations for chylous effusion at our institution over a 2‐year period was performed. Results: A total of 9 diaphragmatic fenestration procedures were performed in 8 patients who had failed medical management of chylous pleural effusions. All procedures except 1 were performed on the right side. The median age at time of procedure was 4.6 months (range, 3 weeks to 14 months). The average time between primary congenital cardiac surgery and fenestration was 26 days (range, 4–53 days). Three patients had single ventricle repair. Average time of chest tube removal after procedure was 4 days. Average time to extubation was 3 days. All patients but 1 were able to advance to full feedings without reaccumulation of chylous effusion within 12 days. No complications developed in the patients. Recurrent effusion over a median follow‐up period of 19 months did not develop in the patients. Conclusions: Diaphragmatic fenestration is an effective and safe strategy for management of persistent chylous effusions after congenital cardiac surgery.