Evidence-based management of chylothorax in infants

Pleurodesis using OK-432 for persistent pleural effusion after cardiac surgery in the neonatal period or early infancy

OBJECTIVE

To evaluate the efficacy of pleurodesis using OK-432 after cardiac surgery in the neonatal period or early infancy.

METHODS

We retrospectively reviewed the data of 11 consecutive patients who underwent cardiac surgery in the neonatal period or early infancy and pleurodesis using OK-432 for persistent postoperative pleural effusion in two institutions.

RESULTS

The median age at surgery was 8 days (interquartile range [IR], 2-18) with a body weight of 2.84 kg (IR, 2.30-3.07). The maximum amount of pleural drainage before pleurodesis was 94.7 (IR, 60.2-107.7) ml/kg/day. Pleurodesis was initiated at postoperative day 20 (IR, 17-22) and performed in bilateral pleural spaces in seven patients and unilateral in four. The median numbers of injection were 4 (IR, 3-6) times per patient and 3 (IR, 2-3) times per pleural space. In 10 patients, pleural effusion was decreased effectively, and drainage tubes were removed without reaccumulation within 15 (IR, 12-28) days after initial pleurodesis. However, in one patient, with severe lymphedema, pleural effusion was uncontrollable, resulting in death due to sepsis. Adverse events were observed in nine patients; temporal deterioration of lung compliance and arterial blood gas occurred in two, insufficient drainage requiring new chest tube(s) in five, temporal atrial tachyarrhythmia in one, and lymphedema in four.

CONCLUSIONS

Pleurodesis using OK-432 is effective and reliable for persistent postoperative pleural effusion in neonates and early infants. Most of the complications, which derived from inflammatory reactions, were temporary and controllable. However, severe lymphedema is difficult to control.

Nutritional markers accompanying acquired chylothorax in infants: a systematic review

CONTEXT

Chylothorax is a well-established acquired complication of thoracic surgery in infants. Current data suggest acquired chylothorax may affect infant growth and nutrition because of a loss of essential nutrients via chylous effusion.

OBJECTIVE

The 3 objectives for this study were: (1) identify nutritional markers affected by the development of acquired chylothorax in infants; (2) highlight the variability in methods used to assess nutritional status and growth in this patient population; and (3) highlight nutritional deficits that can serve as treatment targets during postoperative feeding protocols.

DATA SOURCES

A systematic literature search was conducted between May 31, 2021, and June 21, 2022, using the PubMed, Embase, CINAHL, and Web of Science databases. Search terms included, but were not limited to, "chylothorax," "infants," and "nutrition."

DATA EXTRACTION

Inclusion criteria required studies that measured quantitative markers of nutrition in ≥10 participants aged <1 year with acquired chylothorax. A total of 575 studies were screened and all but 4 were eliminated. Nutritional markers were categorized into 4 different groups: total serum protein level, triglyceride levels, growth velocity, and weight for length.

DATA ANALYSIS

The variation in methods, time points, interventional groups, and nutritional markers did not facilitate a meta-analysis. Risk of bias was assessed using the Cochrane Risk of Bias in Nonrandomized Studies assessment tool.

CONCLUSION

This review highlights the need for reliable quantitative markers of nutrition that will enable providers to assess the nutritional needs of infants with chylothorax. Future studies must focus on measuring markers of nutrition at regular intervals in larger study populations.

Propranolol Therapy for Congenital Chylothorax

Congenital chylothorax is a rare and often severe anomaly without well-established medical therapies. Previously, propranolol use in patients with lymphatic malformations and secondary chylothorax was associated with improvement in clinical signs. We hypothesized that propranolol treatment would be beneficial for severe congenital chylothorax. We reviewed medical records of neonates born from 2015 to 2019 at our tertiary center with a prenatal diagnosis of congenital chylothorax for whom either prenatal or postnatal propranolol therapy was initiated. Inclusion was limited to fetuses diagnosed with severe congenital chylothorax without significant genetic, infectious, or cardiac anomalies, and who underwent prenatal interventions to mitigate consequences of the condition. Propranolol was administered orally to pregnant women at 20 mg 4 times daily and increased to a maximum dose of 40 mg 4 times daily, or to infants at 0.3 mg/kg/d and increased to 1 to 2 mg/kg/d. Primary outcomes were the time course of resolution of ultrasonographical, clinical, and/or radiologic signs of chylothorax after treatment with propranolol. Four neonates met the inclusion criteria. In 2 cases, prenatal initiation of propranolol led to resolution of the chylothoraxes before delivery (38 and 32 days after treatment) on a dose of 40 mg/day 4 times daily. Neonates had a normal postnatal course. Postnatal propranolol was initiated in 2 neonates with respiratory failure when chylothoraces were refractory to standard management. Stabilization and improvement of their pleural effusion was observed by imaging at 29 and 13 days after initiation of propranolol. There were no significant maternal or neonatal complications from prenatal or postnatal propranolol use. Propranolol may be efficacious in treating severe fetal congenital chylothorax.

Chylothorax in newborns after cardiac surgery: a rare complication?

The aim of this study was to analyze patients diagnosed with chylothorax after congenital heart disease surgery among a cohort of neonatal patients, comparing the evolution, complications, and prognosis after surgery of patients who were and were not diagnosed with chylothorax, and to analyze possible risk factors that may predict the appearance of chylothorax in this population. Retrospective and observational study included all neonates (less than 30 days since birth) who underwent congenital heart disease surgery in a level III neonatal intensive care department. We included infants born between January 2014 and December 2019. We excluded those infants who were born before 34 weeks of gestational age or whose birth weight was less than 1800 g. We also excluded catheter lab procedures and patent ductus arteriosus closure surgeries. Included patients were divided into two groups depending on whether they were diagnosed with chylothorax or not after surgery, and both groups were compared in terms of perinatal-obstetrical information, surgical data, and NICU course after surgery. We included 149 neonates with congenital heart disease surgery. Thirty-one patients (20.8%) developed chylothorax, and in ten patients (32.3%), it was considered large volume chylothorax. Regarding the evolution of these patients, 22 infants responded to general dietetic measures, a catheter procedure was performed in 9, and 5 of them finally required pleurodesis. Cardiopulmonary bypass, median sternotomy, and delayed sternal closure were the surgical variables associated with higher risks of chylothorax. Patients with chylothorax had a longer duration of inotropic support and mechanical ventilation and took longer to reach full enteral feeds. As complications, they had higher rates of cholestasis, catheter-related sepsis, and venous thrombosis. Although there were no differences in neonatal mortality, patients with chylothorax had a higher rate of mortality after the neonatal period. In a multiple linear regression model, thrombosis and cardiopulmonary bypass multiplied by 10.0 and 5.1, respectively, the risk of chylothorax and have an umbilical vein catheter decreases risk.

CONCLUSION

We have found a high incidence of chylothorax after neonatal cardiac surgery, which prolongs the average stay and causes significant morbidity and mortality. We suggested that chylothorax could be an underestimated complication of congenital heart disease surgery during the neonatal period.

WHAT IS KNOWN

• Acquired chylothorax in the neonatal period usually appears as a complication of congenital heart disease surgery, being the incidence quite variable among the different patient series (2.5-16.8%). The appearance of chylothorax as a complication of a cardiac surgery increases both mortality and morbidity in these patients, which makes it a quality improvement target in the postsurgical management of this population.

WHAT IS NEW

•Most of the published studies include pediatric patients of all ages, from newborns to teenagers, and there is a lack of studies focusing on neonatal populations. The main strength of our study is that it reports, to the best of our knowledge, one of the largest series of neonatal patients receiving surgery for congenital heart disease in the first 30 days after birth. We have found a high incidence of chylothorax after cardiac surgery during the neonatal period compared to other studies. We suggested that chylothorax could be an underestimated complication of congenital heart disease surgery during this period of life.

Use of Albumin in the NICU: An Evidence-based Review

Albumin is the most abundant protein in human blood with distinctive functions throughout the human body. Low albumin levels are a predictor of mortality as well as disease outcome in children and adults. However, the clinical significance of hypoalbuminemia and the role of albumin infusions in NICUs remain unclear and controversial.

Development of consensus recommendations for the management of post-operative chylothorax in paediatric CHD

OBJECTIVE

A standardised multi-site approach to manage paediatric post-operative chylothorax does not exist and leads to unnecessary practice variation. The Chylothorax Work Group utilised the Pediatric Critical Care Consortium infrastructure to address this gap.

METHODS

Over 60 multi-disciplinary providers representing 22 centres convened virtually as a quality initiative to develop an algorithm to manage paediatric post-operative chylothorax. Agreement was objectively quantified for each recommendation in the algorithm by utilising an anonymous survey. "Consensus" was defined as ≥ 80% of responses as "agree" or "strongly agree" to a recommendation. In order to determine if the algorithm recommendations would be correctly interpreted in the clinical environment, we developed ex vivo simulations and surveyed patients who developed the algorithm and patients who did not.

RESULTS

The algorithm is intended for all children (<18 years of age) within 30 days of cardiac surgery. It contains rationale for 11 central chylothorax management recommendations; diagnostic criteria and evaluation, trial of fat-modified diet, stratification by volume of daily output, timing of first-line medical therapy for "low" and "high" volume patients, and timing and duration of fat-modified diet. All recommendations achieved "consensus" (agreement >80%) by the workgroup (range 81-100%). Ex vivo simulations demonstrated good understanding by developers (range 94-100%) and non-developers (73%-100%).

CONCLUSIONS

The quality improvement effort represents the first multi-site algorithm for the management of paediatric post-operative chylothorax. The algorithm includes transparent and objective measures of agreement and understanding. Agreement to the algorithm recommendations was >80%, and overall understanding was 94%.

The usefulness of OK-432 for the treatment of postoperative chylothorax in a low-birth-weight infant with trisomy 18

Chylothorax is a rare but life-threatening condition in neonates. We herein report the successful use of OK-432 for a low-birth-weight infant with trisomy 18 who developed refractory chylothorax after thoracic surgery. Increasing the concentration of OK-432 seems useful in cases with a lot of pleural effusion.

Neonatal lymphatic flow disorders: central lymphatic flow disorder and isolated chylothorax, diagnosis and treatment using novel lymphatic imaging and interventions technique

PURPOSE OF REVIEW

Neonatal lymphatic disorders (NLDs) are conditions that are relatively rare and difficult to treat. The recent development of lymphatic imaging, such as Dynamic Contrast-Enhanced MR Lymphangiography and Intranodal Lymphangiography has led to a new, better understanding of the anatomical substrate and pathophysiological mechanisms of the diseases. Consequently, this has allowed the development of new targeted therapeutic interventions as well as prognostication for this population with lymphatic flow disorders.

RECENT FINDINGS

The underlying causes of all NLD is an obstruction or altered flow of the central lymphatic flow. Two types of NLD have been described: isolated neonatal chylothorax and central lymphatic flow disorder (CLFD). Isolated neonatal chylothorax can be treated successfully with oil-based contrast (lipiodol) embolization. CLFD secondary to obstruction of the thoraco-venous junction can be successfully treated with surgical thoracic duct-venous anastomosis. CLFD caused by elevated central pressure and/or thoracic duct dysplasia can be treated medically, including with new systemic therapies such as mammalian target of rapamycin inhibitors.

SUMMARY

New diagnostic and interventional tools have recently allowed for classification, prognostication, and targeted interventions for neonatal patients with lymphatic flow disorders. Further research will build on these discoveries.

Sirolimus efficacy in the treatment of critically ill infants with congenital primary chylous effusions

BACKGROUND

Chylothorax can be a presenting symptom of complex lymphatic anomaly in children and is associated with significant respiratory morbidity. Historically, the traditional pharmacological treatment has been octreotide. There are several treatments that have been utilized in the past few years including sirolimus; however, data regarding their efficacy and outcomes is limited. Furthermore, sirolimus has proven efficacy in complex vascular malformations, and hence, its utility/efficacy in infantile primary chylous effusions warrants further investigation.

METHODS

In this retrospective study at Texas Children's Hospital, data were extracted for all infants with chylothorax who were treated with sirolimus between 2009 and 2020. Details regarding underlying diagnosis, comorbidities, and number of days from sirolimus initiation to resolution of effusion were collected.

RESULTS

Initially a total of 12 infants were identified. Among them, seven patients had complete data and were included in the study. Reasons for chylous effusions include presumed complex lymphatic anomaly, generalized lymphatic anomaly, and complex congenital lymphatic anomaly. The mean duration of sirolimus treatment needed for chest tube removal was 16 days, with a median of 19 days and range of 7-22 days. No patients had progression of effusions while on sirolimus.

CONCLUSION

With close monitoring, sirolimus appears to be an effective therapy for pediatric lymphatic effusions even in critically ill infants. The study also demonstrates shorter duration of chest tube requirement after initiation of sirolimus compared to previous studies. Larger multi-institutional studies are needed to further support our findings.

Drugs in Focus: Octreotide Use in Children With Gastrointestinal Disorders

ABSTRACT

Octreotide, a somatostatin analogue, has been used for more than 20 years in children with gastrointestinal bleeding, chylothorax or chylous ascites, intestinal lymphangiectasia, pancreatitis, intestinal dysmotility, and severe diarrhoea; however, until now, there is a lack of randomised clinical trials evaluating the efficacy of this compound in childhood. Hence, we aimed to review the literature in order to determine the evidence of its use and safety in children, using PubMed from 2000 to 2021 with the search terms "octreotide" and "children" and "bleeding or chylous ascites or chylothorax or acute pancreatitis or lymphangiectasia or diarrhoea or intestinal dysmotility".

Successfully Reducing Fat-modified Diet Duration for Treating Postoperative Chylothorax in Children

BACKGROUND

Medical management, primarily a fat-modified diet (FMD), is the mainstay of treatment for the majority of patients with chylothorax. Duration of FMD is traditionally reported as 6 weeks, but no studies demonstrate the shortest effective duration that prevents recurrence of chylothorax. Our aim was to decrease FMD duration to 2 weeks in children with postoperative chylothorax without a significant increase in recurrence.

METHODS

Our single-center study included pediatric (<18 years of age) patients that developed chylothorax within 30 days of cardiac surgery. Patients with cavopulmonary anastomoses were excluded. The pre-intervention cohort was 19 patients diagnosed between 2/2014-6/2015, and the post-intervention cohort was 98 patients from 7/2015-12/2019. FMD duration was decreased from 6 weeks to 4 weeks in May 2016, and to 2 weeks in June 2018. Recurrence was defined as a return of a chylous effusion requiring chest tube placement or hospital readmission within 30 days of resuming a regular diet.

RESULTS

The median duration of FMD decreased from 42 days (interquartile range: 30,43) in the pre-intervention cohort to 26 days (interquartile range: 14,29) post-intervention, with no recurrence of chylothorax in any group. Compliance to the FMD duration instruction in the 6-week, 4-week, and 2-week groups was 100%, 84% and 67% respectively. Compared to the first 6 months, compliance to the 2-week FMD instruction during the final 12 months increased from 40% (6/15) to 79% (26/33).

CONCLUSIONS

At our center, FMD duration decreased from 6 weeks to 2 weeks without any recurrence of chylothorax.

Propranolol treatment for chylothorax after congenital cardiac surgery

OBJECTIVE

Postoperative chylothorax causes significant morbidities in pediatric patients with cardiac disease. New treatment approaches based on evolving understanding of underlying lymphatic dysfunction are being developed. We hypothesized that propranolol reduces morbidities and duration of chest tube requirement in high-output chylous effusion.

METHODS

The postoperative courses of 50 pediatric patients with cardiac disease and high-output chylous effusion (control, n = 25; propranolol-treated, n = 25) were reviewed, including morbidities, length of hospitalization, and duration of chest tube requirement. Statistical analysis was performed using Welch's t test, Kruskal-Wallis tests for continuous variables, and chi-square and Fisher exact tests for categorical variables. Univariable logistic regression was used to determine predictors of response.

RESULTS

Propranolol response was defined as 80% or more drainage reduction in 9 days or less. Treated patients were grouped into responders (<9 days) and nonresponders (>10 days). Neither initial amount of drainage (P = .12) nor day of propranolol initiation (P = .17) correlated with response. When compared with controls and nonresponders, responders had significantly fewer days with chest tube requirement (P < .01), infection (P < .0002), and thrombus (P = .005), and shorter hospitalization (P < .05). All patients had low serum albumin, although nonresponders had significantly decreased serum albumin when compared with responders and control patients (P < .002), and were more likely to receive albumin replacement (P < .01). Malnutrition was prevalent in all patient groups.

CONCLUSIONS

Responders to propranolol had significantly less morbidity and duration of chest tube requirement when compared with control patients and nonresponders. Nonresponders did not have worse outcomes than control patients. We conclude that propranolol may be an effective treatment of patients with refractory chylothorax.

Congenital Chylothorax of the Newborn: A Systematic Analysis of Published Cases between 1990 and 2018

BACKGROUND

Congenital chylothorax (CCT) of the newborn is a rare entity but the most common cause of pleural effusion in this age-group. We aimed to find the optimal treatment strategy.

MATERIAL AND METHODS

A PubMed search was performed according to the PRISMA criteria. All cases were analyzed according to prenatal, perinatal, and postnatal treatment modalities and follow-ups.

RESULTS

We identified 753 cases from 157 studies published between 1990 and 2018. The all-cause mortality rate was 28%. Prematurity was present in 71%, male gender dominated 57%, mean gestational age was 34 weeks, and birth weight was 2,654 g. Seventy-nine percent of newborns had bilateral CCT, the most common associated congenital anomalies with CCT were pulmonary lymphangiectasia and pulmonary hypoplasia, and the most common chromosomal aberrations were Down, Noonan, and Turner syndromes, respectively. Mechanical ventilation was reported in 381 cases for mean 17 (range 1-120) days; pleural punctuations and drainages were performed in 32% and 64%, respectively. Forty-four percent received total parenteral nutrition (TPN) for mean 21 days, 46% medium-chain triglyceride (MCT) diet for mean 37 days, 20% octreotide, and 3% somatostatin; chemical pleurodesis was performed in 116 cases, and surgery was reported in 48 cases with a success rate of 69%. In 462 cases (68%), complete restitution was reported; in 34 of 44 cases (77%), intrauterine intervention was carried out.

CONCLUSION

Respiratory support, pleural drainages, TPN, and MCT diet as octreotide remain to be the cornerstones of CCT management. Pleurodesis with OK-432 done prenatally and povidone-iodine postnatally might be discussed for use in life-threatening CCT.

Dual imaging lymphangiography guided treatment of infantile chylothorax

Chylothorax is a potentially fatal postoperative complication of neck, thoracic, and abdominal surgery in children. We report the case of a 3-month-old infant who developed persistent chylothorax with respiratory insufficiency successfully managed using a microsurgical technique and intraoperative embolotherapy. This was achieved using a combination of intermittent digital X rays and live near-infrared fluorescence imaging we have termed "dual imaging lymphangiography" to guide therapy in real time. The chylothorax resolved and the patient returned to normal diet without recurrence. This microsurgical approach with dual imaging lymphangiography provides a useful tool for intraoperative visualization and treatment of complicated chylothoraces.

Erworbener Chylothorax im Säuglingsalter

Es wird über den Fall eines 8‑monatigen Säuglings mit einem Chylothorax unklarer Genese berichtet. Ein Stridor, zunehmende respiratorische Beeinträchtigung und, bedingt durch den hohen Eiweißverlust, ausgeprägte Ödeme waren die relevantesten klinischen Merkmale. Die bekannten konservativen Therapien wie fettfreie enterale Ernährung unter Substitution von „medium-chain triglycerides“(MCT)-Fetten, gefolgt von Nahrungskarenz und parenteraler Ernährung sowie die Gabe des Somatostatinanalogons Octreotid konnten trotz langer Therapiedauer keine Besserung erzielen. Erst der Einsatz von thorakoskopisch eingebrachten Titan-Clips brachte letztlich den gewünschten Erfolg.

Medical Interventions for Chylothorax and their Impacts on Need for Surgical Intervention and Admission Characteristics: A Multicenter, Retrospective Insight

The incidence of chylothorax is reported from 1-9% in pediatric patients undergoing congenital heart surgery. Effective evidenced-based practice is limited for the management of post-operative chylothorax in the pediatric cardiac intensive care unit. The study characterizes the population of pediatric patients with cardiac surgery and chylothorax who eventually require pleurodesis and/or thoracic duct ligation; it also establishes objective data on the impact of various medical interventions. Data were obtained from the Pediatric Health Information System database from 2004-2015. Inclusion criteria for admissions for this study were pediatric admissions, cardiac diagnosis, cardiac surgery, and chylothorax. These data were then divided into two groups: those that did and did not require surgical intervention for chylothorax. Other data points obtained included congenital heart malformation, age, gender, length of stay, billed charges, and inpatient mortality. A total of 3503 pediatric admissions with cardiac surgery and subsequent chylothorax were included. Of these, 236 (9.4%) required surgical intervention for the chylothorax. The following cardiac diagnoses, cardiac surgeries, and comorbidities were associated with increased odds of surgical intervention: d-transposition, arterial switch, mitral valvuloplasty, acute kidney injury, need for dialysis, cardiac arrest, and extracorporeal membrane oxygenation. Statistically significant medical interventions which did have an impact were specific steroids (hydrocortisone, dexamethasone, methylprednisolone) and specific diuretics (furosemide). These were significantly associated with decreased length of stay and costs. Dexamethasone, methylprednisolone, and furosemide were associated with decreased odds for surgical intervention. These analyses offer objective data regarding the effects of interventions for chylothorax in pediatric cardiac surgery admissions. Results from this study seem to indicate that most post-operative chylothoraxes should improve with furosemide, a low-fat diet, and steroids.

Should Newborns with Refractory Chylothorax Be Tried on Higher Dose of Octreotide?

Chylothorax is a rare but life-threatening condition in newborns, often requiring a prolonged hospital stay. To date, no unified guidance exists for best management approach. Octreotide, a somatostatin analogue, has been used to treat neonatal chylothorax due to its effect on the splanchnic circulation and lipid absorption. It is administered either subcutaneously or intravenously; for the latter, a dose range between 1 and 10 µg/kg/h is most commonly used. However, the optimal dose and way of administration remain unclear. Here, we report 2 newborn cases with large volume chylothorax (>500 mL/day), one with congenital chylothorax and one following a repair of a congenital diaphragmatic hernia (post-operative form). In both cases, a significant and sustained reduction in the volume of evacuated chyle was only seen once the dose of intravenous octreotide was increased to 20 µg/kg/h. We suggest that high-dose octreotide can be considered in seemingly refractory cases of neonatal chylothorax.

Combination Therapy with Etilefrine and Pleurodesis for Refractory Congenital Chylothorax

Etilefrine, a sympathomimetic agent, is reportedly effective against postoperative chylothorax. However, its effectiveness in treating congenital chylothorax was unknown. We report herein a case of refractory congenital chylothorax treated with etilefrine in a late preterm neonate with massive fetal chylous pleural effusion. The chylothorax was unresponsive to previous treatments, including dietary and pharmacological treatment and thoracic duct ligation. The pleural effusion decreased after intravenous etilefrine was begun on day of life (DOL) 84 and resolved after the addition of chemical pleurodesis with OK-432 on DOL 90. This combination therapy may be a viable treatment option for cases of congenital chylothorax that are unresponsive to other treatments.

Efficacy of Early Pleurectomy for Severe Congenital Chylothorax

BACKGROUND

Severe congenital chylothorax (SCC) may result in respiratory failure, malnutrition, immunodeficiency, and sepsis. Although typically managed with bowel rest, parenteral nutrition, and octreotide, persistent chylothoraces require surgical management. At our institution, a pleurectomy, unilateral or bilateral, in combination with mechanical pleurodesis and thoracic duct ligation is performed for SCC, and we describe our approach and outcomes.

MATERIALS AND METHODS

We reviewed over 15-year period neonatal patients with SCC managed surgically with pleurectomy after medical therapy was unsuccessful. Patients were divided into two groups: those who underwent pleurectomy within 28 d of diagnosis (early group) and those who underwent pleurectomy after 28 d (late group). Resolution of chylothorax was defined by the absence of clinical symptoms as well as absent or minimal pleural effusion on chest X-ray.

RESULTS

Of 40 patients diagnosed with SCC over the study period, 15 underwent pleurectomy, eight early [mean time to operation = 20 (IQR 17, 23) d] and 7 late [59 (42, 75) d, P = 0.001]. Overall survival was 67% (10 of 15). Seven of 8 (88%) neonates who underwent early pleurectomy survived versus 3 of 7 (43%) who underwent late pleurectomy (P = 0.07). Length of stay was lower in the early group than the late group [73 (57, 79) versus 102 (109, 213) d, P = 0.05]. All patients who survived to discharge had resolution of their chylothorax.

CONCLUSIONS

Pleurectomy with mechanical pleurodesis and thoracic duct ligation is effective in the management of severe congenital chylothorax. When performed earlier, pleurectomy for severe congenital chylothorax may be associated with improved survival and shorter hospital length of stay.

Chemical pleurodesis and somatostatin in treating spontaneous chylothorax in pediatric patients: a retrospective analysis and review of the literature

BACKGROUND

Chylothorax is a rare disease, defined as an abnormal accumulation of chylous lymphatic effusion in thoracic cavity, with a high mortality rate in pediatric patients. At present, there are few studies on the treatment of pediatric chylothorax, and conservative treatments like somatostatin (SST) and pleurodesis are performed empirically. SST has been used for treating pediatric chylothorax over 20 years, and povidone-iodine chemical pleurodesis (PICP) is adopted in recent years with a high cure rate, but both the effect are still uncertain. The safety and efficacy of SST and PICP in treating pediatric chylothorax was compared in this study.

METHODS

From January 2009 to May 2020, 27 pediatric chylothorax patients who accepted life support, SST and PICP treatment were retrospectively reviewed in this study. Their medical history, clinical manifestations, pleural effusion examinations, treatment methods, effects, and complications were screened. PICP and SST was performed in 19 and 8 children, respectively. Each patient was followed up after discharge from the hospital.

RESULTS

After admission, chest X-ray and ultrasound diagnosed pleural effusion in 27 patients (18 males and 9 females), including 13 and 6 cases on the left and right side, and 8 cases on both sides. In the pleural effusion, the mean leukocyte count was (9,826±9,482)×10⁶/L, the mean lymphocyte ratio was (84.82±6.58)%, the mean triglyceride content was 7.11±6.63 mmol/L. In PICP and SST group, the mean length of stay was 38.42±19.42 and 35.13±12.72 d (P=0.664), the mean time of thoracic drainage was 24.58±16.34 and 19.63±8.88 d (P=0.440), the mean time of parenteral nutrition was 27.16±18.29 and 25.25±13.52 d (P=0.793), respectively. PICP was performed for 3.16±2.27 times, and SST was used for 14.75±9.08 d with the dosage of 0.5 to 10 µg/kg/hour. After the treatment, all patients in PICP group had mild chest pain and low-grade fever, and 12 cases were observed with transient decrease of oxygen saturation. Eight patients in SST group had nausea and vomit, and 1 child had diarrhea simultaneously. Both were cured by symptomatic treatment, thoracic drainage and discontinuing using SST. Three children were diagnosed with refractory chylothorax and cured by PICP after SST. Pleural effusion in 27 patients was finally absorbed. All of them achieved a clinical cure successfully, and there was no recurrence during discharge follow-up.

CONCLUSIONS

PICP has a high success rate and few adverse reactions in treating spontaneous chylothorax in pediatric patients, expected to be a new treatment option for pediatric chylothorax after SST.

Growth of cardiac infants with post-surgical chylothorax can be supported using modified fat breast milk with proactive nutrient-enrichment and advancement feeding protocols; an open-label trial

BACKGROUND & AIM

Previously we showed that modified fat breast milk (MFBM) facilitated resolution of post-surgical chylothorax in cardiac infants, but their weight-for-age and length-for-age z-scores declined over the ≥6-week treatment duration. Our aim was to evaluate the growth of infants diagnosed with post-surgical chylothorax and fed according to one of two proactive feeding protocols using MFBM or a high medium triglyceride (MCT)-containing formula (standard of care).

METHODS

In this open-label trial, infants who were receiving >50% of their enteral feeds as breast milk prior to chylothorax diagnosis were randomized to receive their enteral feeds according to one of two proactive MFBM protocols: Target Fortification (n = 8), where the protein concentration of defatted breast milk was measured weekly and multi- and single-nutrient modulars were added to provide 3.5 g/kg/day of protein; or Higher Initial Concentration (n = 8), where defatted breast milk was initially fortified to an energy and nutrient level higher than that of unmodified breast milk (80kcal/100 ml; 2.2 g/100 ml protein). A third nonrandomized group of infants (n = 8) received high MCT formula (68kcal/100 ml; 2.3 g/100 ml protein). The intervention lasted for a minimum of 6-weeks after chest tube removal and continued after discharge. Weekly weight, length and head circumference (HC) measurements were completed.

RESULTS

At enrolment, there was no statistically significant differences in mean (±SD) weight-for-age (-1.6 ± 0.9, n = 24), length-for-age (-1.3 ± 0.8), or HC-for-age (-0.9 ± 1.0) z-scores among groups. Changes in mean weight- (-0.3 ± 0.9, n = 23), length- (0.1 ± 0.6) and HC-for-age (0.2 ± 0.6) z-scores did not differ among groups over the treatment period. There was no difference in duration or volume of chest tube drainage across groups.

CONCLUSION

Use of proactive MFBM feeding protocols both resolve chylothorax and support growth in infants following cardiothoracic surgery.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02577419).

Evaluating the Use of Octreotide for Acquired Chylothorax in Pediatric Critically Ill Patients Following Cardiac Surgery

OBJECTIVES

To evaluate the impact of octreotide on time to resolution of chylothorax compared with conventional therapy. Secondary outcomes include the following: time to reduction of chest tube output by 20%, additional surgeries for chylothorax, hospital length of stay, in-hospital mortality, and adverse drug reactions.

METHODS

We retrospectively evaluated the efficacy of octreotide vs conventional therapy for treatment postoperative chylothorax in pediatric patients in the cardiac ICU following surgery for congenital heart disease between October 2008 and June 2017.

RESULTS

Final analysis included 32 patients with chylothorax who met inclusion criteria. Patients who received octreotide had a longer duration of chest tube drainage than those who received conventional therapy (24 vs 9 days, p < 0.001). Resolution of chylothorax was achieved in 13 of 16 (81.3%) octreotide patients and 16 of 16 (100%) conventional patients (p = 0.178). There was a comparable time to reduction by 20% in drainage (6 vs 8 days, p = 0.337). There was no significant correlation between time after starting conventional management and reduction chylous output in either the octreotide or conventional therapy group (p = 0.809, p = 0.107, respectively). However, there was a significant and moderate correlation between octreotide and reduction in a chylous output following initiation of octreotide (R ² = 0.464, p = 0.021).

CONCLUSIONS

Octreotide is potentially a safe and effective therapy for treatment in pediatric patients with refractory chylothorax following surgery for congenital heart disease.

Comparison of postoperative chylothorax in infants and children with trisomy 21 and without dysmorphic syndrome: Is there a difference in clinical outcome?

INTRODUCTION

Children with trisomy 21 are prone to postoperative chylothorax, caused by malformation of the lymphatic system, after cardiac surgery. The clinical course of patients diagnosed with postoperative chylothorax and trisomy 21 was compared to that of patients without dysmorphic syndromes. Additionally, differences between the groups in composition, amount, and duration of chyle were analyzed to better understand chylothorax in patients with trisomy 21.

MATERIALS AND METHODS

Retrospective cohort study using inpatient clinical databases during a 10-year period.

RESULTS

A total of 2255 patients underwent cardiac operations during the period, of whom 160 (7.1%) patients were diagnosed with trisomy 21. Chylothorax developed in 122 children; 89 patients were included in our study. Of 160 trisomy 21 patients, 27 (16.9%) developed postoperative chylothorax compared to 62 (3%) of 2095 patients without dysmorphic syndromes (p = <0.001). Time on ventilation, stay in intensive care, hospital stay, mortality, and composition of chylous effusion did not differ between groups. The rate of thrombosis was significantly lower (p = 0.02) in the trisomy 21 group.

CONCLUSION

Children with trisomy 21 and congenital heart disease are more prone to developing chylothorax after heart surgery than those without dysmorphic syndromes. However if they develop this postoperative complication, mortality, chylous composition, time in ICU, and duration of hospital stay is not different to from that of other infants or children with this complication. This is important information for the medical specialists involved and is helpful in counseling parents of children with trisomy 21 undergoing heart surgery.

LEVEL OF EVIDENCE

This is a treatment study evidence level III.

Octreotide Use in Neonates: A Case Series

Background and Objective

Octreotide is a somatostatin analogue and has been used off-label for a variety of conditions. There are no specific guidelines for the use of octreotide in neonates and its safety and efficacy have not been systematically evaluated. The objective of this study is to present our experience of using octreotide therapy in neonates.

Methods

This is a retrospective study of neonates who received octreotide therapy during their hospital stay over a 15 years period (2003–2017) in a tertiary neonatal centre. The demographic details and indications of octreotide therapy including time of initiation, route, dose, duration and adverse effects of therapy were noted. The clinical course following octreotide administration was also analysed.

Results

Eleven neonates received octreotide therapy during the study period, of which nine had chylothorax and two had chylous ascites. Resolution of the chylous effusion with octreotide therapy was achieved in 4 out of 11 (36.3%) of the cases. The median duration of octreotide therapy in cases with successful resolution was 17.5 days. With the exception of minor side effects such as hyperglycaemia, none of the patients had any significant side effects that required discontinuation of therapy.

Conclusion

Octreotide was used safely as an adjunctive therapy for the treatment of chylothorax and chylous ascites in neonates. However, larger prospective controlled trials are required to establish the optimal dose, time of initiation, duration and efficacy of octreotide therapy in neonates.

Lymphovenous Anastomosis for the Treatment of Chylothorax in Infants: A Novel Microsurgical Approach to a Devastating Problem

With the expanding horizon of microsurgical techniques, novel treatment strategies for lymphatic abnormalities are increasingly reported. Described in this article is the first reported use of lymphovenous anastomosis surgery to manage recalcitrant chylothoraces in infants. Chylothorax is an increasingly common postoperative complication after pediatric cardiac surgery, with a reported incidence of up to 9.2 percent in infants. Although conservative nutritional therapy has a reported 70 percent success rate in this patient population, failed conservative management leading to persistent chylothorax is associated with a significant risk of multisystem complications and mortality. Once conservative medical strategies are deemed unsuccessful, surgical or radiologic interventions, such as percutaneous thoracic duct embolization or ligation, are often attempted. However, these procedures lack high-level evidence in the infant population and remain a challenge, given the small size of the lymphatic vessels. As such, we report our experience with performing lymphovenous anastomoses in two infants who had developed refractory chylothoraces secondary to thoracic duct injury following cardiac surgery for congenital cardiac anomalies. In addition, this article reviews the relevant pathophysiology of chylothoraces, current treatment algorithm following failed conservative management, and potential role of the microsurgeon in the multidisciplinary management of this life-threatening problem. As part of the evolving microsurgery frontier, physiologic operations, such as lymphovenous anastomosis, may have a considerable role in the management of refractory pediatric chylothoraces. In our experience, lymphovenous anastomosis can restore normal lymphatic circulation within 1 to 2 weeks, liberate patients from mechanical ventilation, and enable expeditious return to enteral feeding.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Octreotide for congenital and acquired chylothorax in newborns: A systematic review

AIM

Chylothorax is a rare but life-threatening condition in newborns. Octreotide, a somatostatin analogue, is widely used as a therapeutic option in neonates with congenital and acquired chylothorax, but its therapeutic role has not been clarified yet.

METHODS

We performed a systematic review to assess the efficacy and safety of octreotide in the treatment of congenital and acquired chylothorax in newborns. Comprehensive research, updated till 31 October 2017, was performed by searching in PubMed, MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) databases using the MeSH terms 'octreotide' and 'chylothorax'. Both term and preterm newborns with congenital or acquired chylothorax treated with octreotide within the 30th day of life were included. Octreotide treatment was considered effective if a progressive reduction/ceasing in drained chylous effusion occurred.

RESULTS

A total of 39 articles were included. Octreotide was effective in 47% of patients, with a slight but not significant difference between congenital (30/57; 53.3%) and acquired (9/27; 33.3%) chylothorax (P = 0.10). Marked variation in octreotide regimen was observed. The most common therapeutic scheme was intravenous infusion at a starting dose of 1 μg/kg/h, gradually increasing to 10 μg/kg/h according to the therapeutic response. Side effects were reported in 12 of 84 patients (14.3%). Only case reports were included in this review due to the lack of randomised controlled trials.

CONCLUSION

Octreotide is a relatively effective and safe treatment option in neonates with chylothorax, especially for the congenital forms.

Fetal intervention for congenital chylothorax is associated with improved outcomes in early life

BACKGROUND

Congenital chylothorax (CC) can have devastating consequences for neonates. We sought to determine the outcomes of cases treated at our institution and evaluate the role of fetal intervention.

MATERIALS AND METHODS

With Institutional Review Board approval, patients treated at our institution 09/2006-04/2016 with CC were reviewed. History and outcomes were compared between patients undergoing fetal intervention (fetal group) and patients who did not (control group).

RESULTS

Twenty-three patients were identified. Mean gestational age at birth was 35 wk. Overall mortality was 30% (7 patients). Nineteen patients (83%) were prenatally diagnosed, and 10 patients (43%) underwent fetal intervention. Birth weight was significantly lower in the fetal group compared to the control group (median interquartile range [IQR]; 2.5 [2.3-3.0] versus 3.3 [2.6-3.7] kg, P = 0.02). Apgar scores were significantly higher in the fetal group than the control group at 1 and 5 min (median [IQR]; 6 [4-8] versus 1 [1-2], P = 0.005 and 8 [7-9] versus 2 [2-6], P = 0.008, respectively). For those patients with prenatal diagnosis of CC and hydrops fetalis, thrombosis and lymphopenia were both improved in the fetal group (thrombosis 0% versus 40%, P = 0.03; lymphocyte nadir [median {IQR}] 1.5 [0.6-2.9] versus 0.1 [0.05-0.2], P = 0.02). Duration of support with mechanical ventilation was significantly shorter in the fetal group (median [IQR]; 1 [0-40] versus 41 [29-75] d, P = 0.04).

CONCLUSIONS

Fetal intervention for CC is associated with improved Apgar scores and decreased ventilator days and complications in patients with hydrops fetalis. Fetuses with chylothorax, especially those with hydrops, should be referred to a fetal center for evaluation.

Lymphatic dysfunction in critical illness

PURPOSE OF REVIEW

The essential role of the lymphatic system in fluid homeostasis, nutrient transport, and immune trafficking is well recognized; however, there is limited understanding of the mechanisms that regulate lymphatic function, particularly in the setting of critical illness. The lymphatics likely affect disease severity and progression in every condition, from severe systemic inflammatory states to respiratory failure. Here, we review structural and functional disorders of the lymphatic system, both congenital and acquired, as they relate to care of the pediatric patient in the intensive care setting, including novel areas of research into medical and procedural therapeutic interventions.

RECENT FINDINGS

The mainstay of current therapies for congenital and acquired lymphatic abnormalities has involved nonspecific medical management or surgical procedures to obstruct or divert lymphatic flow. With the development of dynamic contrast-enhanced magnetic resonance lymphangiography, image-directed percutaneous intervention may largely replace surgery. Because of new insights into the mechanisms that regulate lymphatic biology, pharmacologic inhibitors of mTOR and leukotriene B4 signaling are each in Phase II clinical trials to treat abnormal lymphatic structure and function, respectively.

SUMMARY

As our understanding of normal lymphatic biology continues to advance, we will be able to develop novel strategies to support and augment lymphatic function during critical illness and through convalescence.

Causes and manifestations of chylothorax in children in China: Experience from a children's medical center, 2007-2017

IMPORTANCE

Chylothorax is the most common cause of pleural effusion in neonates and relatively rare in children. It can cause significant respiratory morbidity. Many clinical entities may contribute to chylothorax.

OBJECTIVE

To investigate the causes and manifestations of chylothorax in infants and children in China.

METHODS

Case records of 107 cases with chylothorax seen in Beijing Children's Hospital from 2007 to 2017 were retrieved and analyzed; follow-up was carried out by telephone.

RESULTS

Of 107 cases, 58.9% (63/107) were primary chylothorax (PC) and 41.1% (44/107) were secondary chylothorax (SC). Also, 36.4% (39/107) were neonatal chylothorax (NC) and 35.5% (38/107) were postoperative chylothorax. In PC with a verified lymphatic anomaly, there was one case of diffuse pulmonary lymphangiomatosis (DPL) and six cases of generalized lymphatic anomaly (GLA), which accounted for 6.5% (7/107) of cases. In most patients, chylothorax was alleviated by conservative treatment based on total parenteral nutrition (TPN); 13.1% (14/107) of cases needed further surgery. In NC, the median duration of TPN was 9 days, but 10 of 20 cases who improved had recurrence upon re-introduction of a fat-free diet, which was alleviated by further TPN. The duration of hospitalization was (23 ± 14) days for congenital chylothorax. Upon long- term follow-up, except for GLA and DPL, most patients were doing well without recurrence.

INTERPRETATION

NC and postoperative chylothorax are the common subtypes. TPN is effective for most patients. Despite a prolonged and fluctuating clinical course, most patients had a good long-term prognosis.

Prenatal factors associated with neonatal survival of infants with congenital chylothorax

OBJECTIVES

Congenital chylothorax is a rare disease and prognostic factors are key element in properly informing parents. This study aimed at determining the prenatal factors associated with neonatal survival in a cohort of liveborn infants with congenital chylothorax.

STUDY DESIGN

Observational monocentric cohort study including all liveborn neonates consecutively admitted for congenital chylothorax.

RESULTS

Neonatal mortality was 32% (16/50). Prematurity (or birth weight), persistence of hydrops at birth and the absence of thoracoamniotic shunt procedure were significantly associated with mortality, whereas prenatal diagnosis of pleural effusion, side of pleural effusion, hydrops fetalis and amniodrainage were not. In case of prenatal diagnosis of hydrops fetalis, the reversal in utero of hydrops fetalis was significantly associated with survival (P=0.001). In case of thoracoamniotic shunting, the interval between thoracoamniotic shunting intervention and delivery was significantly longer for patients who survived (P=0.03).

CONCLUSIONS

Thoracoamniotic shunting and reversal of hydrops significantly improves survival, whereas prematurity worsened outcome of liveborn infants with congenital chylothorax. Our data also suggest that the interval between thoracoamniotic shunting and birth appears to be crucial; the longer the interval, the more likely is the reversal of antenatal hydrops and neonatal survival.

Uses and misuses of albumin during resuscitation and in the neonatal intensive care unit

Albumin is one of the most abundant proteins in plasma and serves many vital functions. Neonatal concentrations vary greatly with gestational and postnatal age. In critically ill neonates, hypoalbuminemia occurs due to decreased synthesis, increased losses or redistribution of albumin into the extravascular space, and has been associated with increased morbidities and mortality. For that reason, infusion of exogenous albumin as a volume expander has been proposed for various clinical settings including hypotension, delivery room resuscitation, sepsis and postoperative fluid management. Albumin is often prescribed in infants with hypoalbuminemia, hyperbilirubinemia, and protein-losing conditions. However, the evidence of these practices has not been reviewed or validated. Albumin infusion may initiate highly complex processes that vary according to the individual and disease pathophysiology. Indeed, it may be associated with harms when misused. In this review, we critically appraise the scientific evidence for administering albumin in most conditions encountered in the neonatal intensive care unit, while emphasizing the benefits and risks associated with their use.

Congenital chylothorax

Congenital chylothorax (CC) results from multiple lymphatic vessel anomalies or thoracic cavity defects and may accompany other congenital anomalies. Fetal chylothorax may increase the risk of death and complications from pleural space lymphatic fluid accumulation, which compromises lung development, pulmonary, and cardiovascular function and from complications arising from the loss of drained lymphatic contents. Prenatal interventions might improve survival in severe cases of fetal chylothorax. The neonatal treatment strategy is generally supportive with interventions that include thoracostomy drainage and attempts to decrease chyle flow using a stepwise approach that begins with the least invasive means. Evidence-based treatment choices are lacking and are much needed. Most cases of CC resolve with time even without specific lymphatic system studies to identify the exact pathology. Expertise in performing lymphatic studies is not universally available. Data on both efficacy and safety of the various therapeutic options are needed to determine the best approach to the treatment of CC.