Post-Operative Chylothorax in Children Undergoing Congenital Heart Surgery

Risk Factors of Chylothorax After Congenital Heart Surgery in Infants: A Single-Centre Retrospective Study

Background

Studies of chylothorax after congenital heart disease in infants are rare. Chylothorax has a higher incidence in infancy, but its risk factors are not well understood.

Objective

The purpose of this study is to investigate the risk factors of chylothorax after congenital heart surgery in infants.

Methods

This retrospective study included 176 infants who underwent congenital heart disease surgery at the Guangdong Cardiovascular Institute, China, between 2016 and 2020. According to the occurrence of chylothorax, the patients were divided into a control group (n = 88) and a case group (n = 88). Univariate and multivariate logistic regression were performed to analyse the incidence and influencing factors of chylothorax after congenital heart surgery in infants.

Results

Between 2016 and 2020, the annual incidence rate fluctuated between 1.55% and 3.17%, and the total incidence of chylothorax was 2.02%. Multivariate logistic regression analysis showed that postoperative albumin (p = 0.041; odds ratio [OR] = 0.095), preoperative mechanical ventilation (p = 0.001; OR = 1.053) and preterm birth (p = 0.002; OR = 5.783) were risk factors for postoperative chylothorax in infants with congenital heart disease.

Conclusion

The total incidence of chylothorax was 2.02% and the annual incidence rate fluctuated between 1.55% and 3.17% between 2016 and 2020. Premature infants, longer preoperative mechanical ventilation and lower albumin after congenital heart surgery may be risk factors for chylothorax. In addition, infants with chylothorax are inclined to be infected, need more respiratory support, use a chest drainage tube for longer and remain longer in hospital.

Lymphoscintigraphy Findings are Associated with Outcome in Children with Chylothorax After Cardiac Surgery

Postoperative chylothorax in patients with congenital heart diseases (CHD) results in poor outcomes if anatomical and functional abnormalities of the lymphatic system are present. While these abnormalities are typically diagnosed by intranodal lymphangiography and dynamic contrast magnetic resonance lymphangiography, the usefulness of lymphoscintigraphy in these patients has not been evaluated. Between January 2019 and December 2021, 28 lymphoscintigraphies were performed in our institution for investigating prolonged pleural effusion after cardiac surgery. The images were assessed by three board-certified pediatric cardiologists retrospectively to determine the likelihood of a central lymphatic flow disorder. The likelihood was scored (range 1-3) based on structural abnormalities and congestive flow in the lymphatic system. Those scores were summed and the likelihood was categorized as low to intermediate (< 8 points) or high (8 or 9 points). Median age at lymphoscintigraphy was 129 days (IQR, 41-412 days), it was performed at a median of 22 days (IQR, 17-43) after surgery, and median score was 6 points (IQR, 4-7.5). Kendall's coefficient of concordance (0.867; p < 0.05) indicated high inter-rater reliability. Overall survival at 6 months after surgery was 92.5% in the low-to-intermediate group but 68.6% in the high group (p < 0.05), and duration of postoperative thoracic drainage was 27 and 58 days, respectively (p < 0.05). Lymphatic abnormalities detected by lymphoscintigraphy were associated with poorer outcomes. Lymphoscintigraphy was thought to be useful in assessing anatomic and functional lymphatic abnormalities, despite its minimal invasiveness.

Chylothorax After Heart Surgery in Children

Chylothorax is a consequence of a thoracic duct injury that can occur during surgical procedures in patients with congenital heart disease. It is associated with high rates of morbimortality and increased use of clinical and hospital resources. The aim of this study was to evaluate the risk factors, distribution, manifestations, complications, and treatments for chylothorax in patients undergoing cardiac surgery in a tertiary pediatric hospital in southern Brazil. This is a retrospective, quantitative study, in which all medical records (n = 166) of patients with chylothorax after pediatric cardiac surgery between January 2014 and December of 2020 and a matched control group (n = 166) were analyzed. Over the study period, there was an increase in incidence of chylothorax from 4.5% in 2014 to 7.6% in 2020, a trend that has been reported in the literature. After multivariate analysis, the following were identified as risk factors for the diagnosis of chylothorax: genetic syndrome (OR 2.298); prolonged cardiopulmonary bypass time (greater than 120 min) (OR 2.410); fluid overload in the immediate postoperative period (OR 1.110); and SIRS (OR 2.527). Mortality was two times greater (p = 0.021) and there was a higher rate (34.4%) of infection (p < 0.001) in patients who developed chylothorax. In addition, a sensitivity analysis was performed comparing patients with low- and high-output chylothorax (> 20 mL/kg), which confirmed unfavorable outcomes for the latter group. Herein, we show that hemodynamic alterations were important factors for diagnosis. Understanding the risk factors, outcomes, and complications helps early identification and enables the reduction of morbidity and mortality.

Incidence, Risk Factors and Effective Treatment Strategies for Chylothorax After Pediatric Heart Surgeries: Retrospective Analysis of Large Database in Single Institution

Background

Risk factors for postoperative chylothorax in children who had cardiothoracic procedures are not always clear. Due to complex course in post-operative care, It's always challenging to find the risk factors, and their management.

Objective

The aim of our study was to identify the incidence, risk factors and effective treatment approaches for chylothorax after pediatric heart surgery.

Methods

Children who had the cardiac surgery and subsequently developed chylothorax were included in the study. The ratio of the experimental group to the control group was 1:2. Decannulations of extracorporeal membrane oxygenation (ECMO) were not included in the analysis of patient outcomes. For each patient, we keep track of their age, weight, gender, syndrome, RACH-1 scoring, fluid balance, bypass time, clamp time, redo operations, open or close heart surgeries, and rhythm difficulties. Care logs were kept for every single therapy that was administered. Primary outcome was chylothorax, with secondary outcomes included time in the intensive care unit (ICU), length of hospital stay (LOS), and death.

Results

5210 surgeries were performed in six years. 96 patients developed the chylothorax with incidence of 1.8%. In chylothorax group, mean weight was 6.7 ± 4.2, while mean age was 11.7 ± 15.2. Clamp time was 74.5 ± 53.5 versus 39.9 ± 13.7. Mean bypass time was 128.34(76.25) versus 84.3 ± 25.1 with an odds ratio 1.02 (Z test 0.0001). Six (6.3%) children with chylothorax had redo cardiac surgeries in the same admission (p-value 0.01) while none in other. Five (5.2%) cases got operated by thoracotomy, three from left side. Mean Chest tube duration was 10±7.8 days versus 3.8±2.4 in control group. (p-value 0.02). chylothorax resolved (mean resolving time = 4 days) in 76 (79.2%) children with monogen formula. Two patients receive midodrine with no significant effect. Four children underwent surgical repair for chylothorax.

Conclusion

Bypass time linearly increases incidence of chylothorax. Younger age, low weight, syndromic children, redo operations, non-open-heart surgeries, and arrhythmias also contribute to this. Gender, fluid balance, and RACHS-1 Scoring were not significant. While further research and testing are required for the use of midodrine. However, the low-fat formula of Monogen has proven to be an effective treatment.

Octreotide for Acquired Chylothorax in Pediatric Patients Post-Cardiothoracic Surgery for Congenital Heart Disease: A Systematic Review

Chylothorax is a life-threatening complication post-corrective congenital heart surgery. Octreotide is used for treatment of refractory chylothoraces, with no standardized treatment protocol and a paucity of literature describing its efficacy. Our aim was to provide an update on the safety and efficacy of octreotide for the treatment of refractory chylothoraces in neonatal and pediatric patients' post-corrective congenital heart surgery. We performed a systematic review of PubMed, Medline, CINAHL, and Cochrane Library databases. Only intravenous octreotide treatment was included. A total of 621 patients across 27 studies were included. Studies included were 11 case series, 5 case studies, and 11 retrospective cohort studies. Variation in treatment regimens were reported. Treatment efficacy was reported in 95% (23/27) of studies. Definitions of treatment efficacy were reported in 33% (9/27) of studies. No prospective or randomized control trials were available for inclusion. Octreotide efficacy is widely reported despite a lack of standardization on criteria for treatment initiation or what defines an appropriate response to therapy.Please check and confirm whether the edit made to the article title is in order.Yes.

Lymphatic anomalies in congenital heart disease

Congenital heart disease can lead to various lymphatic complications including traumatic leaks, lymphatic overproduction, conduction abnormalities or lymphedema. Advancements in the imaging of central lymphatics and guided interventions have improved outcomes in these children. Dynamic contrast-enhanced magnetic resonance (MR) lymphangiography allows for the assessment of abnormal lymphatic drainage. This technique is preferred for evaluating lymphatic conditions such as plastic bronchitis, chylothorax, chyloptysis, chylopericardium, protein-losing enteropathy and chylous ascites, among other lymphatic disorders. In this review, we discuss lymphatic abnormalities encountered on MRI in children with congenital heart disease. We also briefly review treatment options.

Postoperative Chylothorax in Neonates and Infants after Congenital Heart Disease Surgery-Current Aspects in Diagnosis and Treatment

Postoperative chylothorax is a rare complication following cardiac surgery for congenital heart disease (CHD) in the pediatric population, including neonates and infants. Multiple mechanisms are involved in the development of postoperative chylous effusions, mainly the traumatic injury of lymphatic vessels, systemic venous obstruction and dysfunction of the right ventricle. In this review, we focus on the existing evidence regarding the definition and diagnosis of postoperative chylothorax in children with CHD, as well as current therapeutic approaches, both nutritional and interventional, for the management of these patients. As part of nutritional management, we specifically comment on the use of defatted human milk and its effect on both chylothorax resolution and patient growth. A consensus with regard to several key aspects of this potentially significant complication is warranted given its impact on the cost, morbidity and mortality of children with CHD.