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.

The clinical value of ultrasonic cardiac output monitor in very-low birth-weight and extremely-low-birth-weight infants undergoing PDA ligation

BACKGROUND

Cardiorespiratory instability occurs very often in very-low-birth-weight (VLBW) and extremely-low-birth-weight (ELBW) infants undergoing patent ductus arteriosus (PDA) ligation during the early postoperative period. This study aimed to investigate ultrasonic cardiac output monitor (USCOM) as a bedside tool by evaluating the hemodynamic changes in preterm infants following PDA ligation and assessing factors that may influence these changes.

METHODS

This was a single-center prospective observational study at a third-level neonatal intensive care unit. A total of 33 infants, including 21 VLBW and 12 ELBW infants, were involved. Hemodynamic measurements were performed in these infants using a USCOM preoperatively as well as 0-1 h, 8-10 h, and 24 h postoperatively.

RESULTS

The PDA ligation was associated with reductions of the left ventricular cardiac output (LVCO) (P < 0.001), cardiac index (P < 0.001), flow time corrected (FTC) (P < 0.001), Smith-Madigan inotropy index (SMII) (P < 0.001), oxygen delivery (DO₂) (P < 0.001), and oxygen delivery index (DO₂I) (P < 0.001) and an increase of the systemic vascular resistance index (SVRI) (P < 0.001) at 0-1 h, 8-10 h, and 24 h post-ligation compared with the respective preoperative values. Compared with the respective values at 0-1 h post-ligation, there was no significant difference in the CI, SMII, or FTC at 8-10 h and 24 h post-ligation. However, the SVRI decreased at 8-10 h and 24 h post-ligation. Moreover, the DO₂I increased at 8-10 h and 24 h post-ligation, and the LVCO and DO₂ increased at 24 h post-ligation.

CONCLUSION

Our study confirmed that the hemodynamic changes measured by the USCOM were similar to those measured by echocardiography in previous reports. Thus, USCOM is a useful and convenient bedside tool for assessing hemodynamic changes to guide the use of fluids, inotropic agents, and vasopressors and help modify the post-ligation course, and they may be a surrogate for repeated echocardiography during the early post-ligation period in preterm infants or a preliminary screening method.

[Clinical effects of partially de-epithelized local flaps in repairing tubercular chest wall defects]

Objective: To explore the clinical effects of partially de-epithelized local flaps in repairing tubercular chest wall defects. Methods: A retrospective observational study was conducted. From April 2010 to February 2021, twelve patients who met the inclusion criteria were admitted to the Department of Burns and Plastic Surgery of the Eighth Medical Center of PLA General Hospital, including 9 males and 3 females with age of (42±18) years. The sizes of tubercular chest wall defects of patients were ranged from 4 cm×3 cm×2 cm to 16 cm×8 cm×5 cm, which were all repaired with partial de-epithelized local flaps. The widths of flaps were equal to the widths of the defects, and the lengths of flaps were 2 cm longer than those of the defects. In one patient, the local flap was too large to close the donor site directly by suturing, so an autologous back free medium thickness skin graft was used for repair. In other patients, the collection areas of local flaps were small, and the donor areas of flaps were directly closed. The duration of operation, intraoperative bleeding, and postoperative drainage volume and indwelling time of drainage tube were observed and recorded. In two weeks after operation, the survival, color, and texture of flaps, the presence of subcutaneous hydrops and skin ulcer, and donor site healing including wound disruption, local infection, hematoma were observed. Chest X-ray, CT scan, or nuclear magnetic resonance imaging was performed in one month after operation to check whether new local hydrops and bone destruction occurred in the chest wall defects and the concomitant tuberculose focus of patients. All patients were followed up for more than 6 months to record whether the surgical incisions of the chest wall defects of the patients were complicated by hypertrophic scar, redness, swelling, and sinus. Results: In surgery, the patient had (104±18) min of operation duration, (119±53) mL of intraoperative bleeding, (134±49) mL of cumulative drainage of drainage tube, and (5.3±1.7) days of drainage tube indwelling time. In two weeks after operation, all the grafted local flaps survived, and the color and texture of flaps were similar to the surrounding normal skin. One patient had fluid leakage from the incision of chest wall defect area with the incision partially dehisced, which healed well after a phase Ⅱ operation; no wound infection, subcutaneous hydrops, or wound rupture occurred in other patients. The incisions of donor sites in all the patients healed well and no wound disruption, local infection, or hematoma occurred. One month after operation, no new bone destruction was observed in the operative region by chest imaging examination. Patients were followed up for 6 to 96 months, with one patient having wound swelling, ulceration, and sinus in the operative area of the chest wall defect in 12 months after surgery, which healed after phase Ⅱ operation; the incisions of chest wall defect wounds in other patients healed well and had no scar, redness and swelling, or sinus. Conclusions: Partially de-epithelized local flap could be used in repairing tubercular chest wall defect wounds, with the advantages of flexible flap design, minimal donor site injury, and good postoperative wound healing.

Measurement of inotropy and systemic oxygen delivery in term, low- and very-low-birth-weight neonates using the Ultrasonic Cardiac Output Monitor (USCOM)

Background The aim of this study was to assess the normal values of the Smith-Madigan inotropy index (SMII) and oxygen delivery index (DO2I) in low-birth-weight (LBW) and very-low-birth-weight (VLBW) newborns on the first 3 days of life, and to identify how different degrees of maturity influence cardiovascular alterations during the transitional period compared with term neonates. Methods Twenty-eight VLBW newborns, 46 LBW newborns and 50 normal full-term newborns admitted to our department were studied. Hemodynamics of the left heart were measured in all neonates over the first 3 days using the Ultrasonic Cardiac Output Monitor (USCOM). This was combined with hemoglobin concentration and pulse oximetry to calculate DO2I. Blood pressure was combined with the hemodynamic measures and hemoglobin concentration to calculate SMII. Results SMII showed statistically significant differences among the three groups (VLBW 0.48 ± 0.11; LBW 0.54 ± 0.13; term 0.69 ± 0.17 W/m2 P < 0.001), which was in line with the following myocardial parameters: stroke volume index (SVI) and cardiac index (CI) (P < 0.001 and <0.001). For systemic oxygen delivery (DO2) parameters, significant differences were found for DO2I (P < 0.001) while hemoglobin concentration and pulse oximetry demonstrated no significant differences. In the VLBW group, SMII and DO2I showed no significant change over the 3 days. Conclusion Normal inotropy and systemic DO2I values in VLBW neonates over the first 3 days of life were assessed. SMII and DO2I were significantly lower in VLBW neonates during the first 72 h of life. With increasing birth weight, higher myocardial inotropy and DO2 were found. The addition of USCOM examination to standard neonatal echocardiography may provide further important information regarding cardiac function.

Effects of steam explosion pretreatment and Lactobacillus buchneri inoculation on fungal community of unensiled and ensiled total mixed ration containing wheat straw during air exposure

AIM

To compare the effects of steam explosion and Lactobacillus buchneri inoculation on fungal community in ensiled total mixed ration (TMR) during aerobic exposure.

METHODS AND RESULTS

The TMRs were prepared using wheat straw with or without steam explosion, sweet potato residue, lucerne hay, maize meal and soybean meal, and ensiled with or without L. buchneri inoculation. Fungal communities were detected by high-throughput sequencing. All ensiled TMRs were well ensiled and steam explosion has a major effect on improving aerobic stability. The fungal species, such as Xeromyces bisporus and Cryptococcus victoriae, that dominated in the TMR decreased after ensiling, with a concomitant increase in Candida humilis, Pichia kudriavzevii, Aspergillus flavus and Phanerochaete chrysosporium. Most mould species decreased, with C. humilis and P. kudriavzevii dominating during aerobic exposure.

CONCLUSION

Steam explosion could improve the aerobic stability in ensiled TMR by inhibition of C. humilis.

SIGNIFICANCE AND IMPACT OF THE STUDY

High-throughput sequencing used in this study provides insight into the fungal community in ensiled TMR during aerobic exposure, which could contribute towards elucidating the mechanism by which aerobic deterioration develops.

P6013Evidence for ANTXR2 as a therapeutic target on systemic-to-pulmonary shunt induced pulmonary arterial hypertension

Introduction

Pulmonary arterial hypertension secondary to congenital heart disease (CHD-PAH) with systemic-to-pulmonary shunt is characterized by proliferative vascular remodeling. Excessive proliferation and resistance to apoptosis of pulmonary artery smooth muscle cells (PASMCs) are the primary cellular bases of vascular remodeling. Anthrax toxin receptor 2 (ANTXR2) exhibits anti-proliferative properties. The effects of ANTXR2 on vascular remodeling and systemic-to-pulmonary shunt induced PAH remain unexplored.

Purpose

The purpose of this study was to determine the possible roles of ANTXR2 in the pathogenesis of systemic-to-pulmonary shunt induced PAH and explore its possible mechanisms.

Methods

Lung tissue sections from CHD-PAH patients, systemic-to-pulmonary shunt induced PAH rat model, ANTXR2−/− rats, and PASMCs were used. Immunohistochemistry, real time polymerase chain reaction, Western blot, proliferation, apoptosis, and next generation sequencing (NGS) were performed in this study.

Results

ANTXR2 expression was reduced in severe CHD-PAH patient lung tissue and pulmonary arterioles, as well as in lung tissues from rats with systemic-to-pulmonary shunt induced PAH. Over-expression of ANTXR2 in cultured PASMCs inhibited cell proliferation and promoted apoptosis, while knockdown of ANTXR2 promoted cell proliferation and inhibited apoptosis. Male ANTXR2−/− rats showed more severe percent medial thickness and muscularization of pulmonary arterioles than wild type (WT) rats in basal conditions, and exhibited heavier PAH following exposure to systemic-to-pulmonary shunt. To further determine the underling mechanism, NGS was performed in ANTXR2−/− rat lungs and that of WT littermates. A total of 1319 genes were found to be dysregulated, and biological processes influenced by these differentially expressed genes include negative regulation of blood vessel diameter,vasoconstriction, regulation of blood vessel diameter, regulation of blood vessel size, vascular process in circulatory system, etc.

Conclusion

Our work identifies a novel role for ANTXR2 in systemic-to-pulmonary shunt induced PAH based on the findings that ANTXR2 deficiency could exacerbate systemic-to- pulmonary shunt induced vascular remodeling in the development of PAH. ANTXR2 may be a potential target for CHD-PAH treatment.

Acknowledgement/Funding

Beijing Natural Science Foundation (7172078 and 7172182), the National Major Research Plan Training Program of China (91849111)

Comparison of Arndt-endobronchial blocker plus laryngeal mask airway with left-sided double-lumen endobronchial tube in one-lung ventilation in thoracic surgery in the morbidly obese

This study aimed to evaluate the feasibility and performance of Arndt-endobronchial blocker (Arndt) combined with laryngeal mask airway (LMA) compared with left-sided double-lumen endobronchial tube (L-DLT) in morbidly obese patients in one-lung ventilation (OLV). In a prospective, randomized double-blind controlled clinical trial, 80 morbidly obese patients (ASA I-III, aged 20-70) undergoing general anesthesia for elective thoracic surgeries were randomly allocated into groups Arndt (n=40) and L-DLT (n=40). In group Arndt, a LMA™ Proseal was placed followed by an Arndt-endobronchial blocker. In group L-DLT, patients were intubated with a left-sided double-lumen endotracheal tube. Primary endpoints were the airway establishment, ease of insertion, oxygenation, lung collapse and surgical field exposure. Results showed similar ease of airway establishment and tube/device insertion between the two groups. Oxygen arterial pressure (PaO2) of patients in the Arndt group was significantly higher than L-DLT (154±46 vs 105±52 mmHg; P<0.05). Quality of lung collapse and surgical field exposure in the Arndt group was significantly better than L-DLT (effective rate 100 vs 90%; P<0.05). Duration of surgery and anesthesia were significantly shorter in the Arndt group (2.4±1.7 vs 3.1±1.8 and 2.8±1.9 vs 3.8±1.8 h, respectively; P<0.05). Incidence of hoarseness of voice and incidence and severity of throat pain at the post-anesthesia care unit and 12, 24, 48, and 72 h after surgery were significantly lower in the Arndt group (P<0.05). Findings suggested that Arndt-endobronchial blocker combined with LMA can serve as a promising alternative for morbidly obese patients in OLV in thoracic surgery.

Dynamics of microbial community during ensiling direct-cut alfalfa with and without LAB inoculant and sugar

AIM

To gain deeper insights into the clostridial community dynamics and chemical transformations during the ensiling of alfalfa.

METHODS AND RESULTS

Direct-cut alfalfa silage (with the dry matter content of 240 g kg^-1 ) was prepared with or without the addition of a lactic acid bacterial inoculant and sucrose. Silages were sampled at 0, 3, 7, 14, 28 and 56 days after ensiling and their bacterial community was determined using high-throughput sequencing with a special focus on the clostridial community. A clostridial fermentation occurred in the control silage, with high contents of acetic acid, butyric acid and ammonia nitrogen and Clostridia counts; while the inoculated silage was well preserved, with low pH and high lactic acid content. Lactic acid bacteria dominated the bacterial community during the ensiling process. In the control silage, Weissella confusa, Lactobacillus brevis, Enterococcus mundtii and Pediococcus acidilactici were identified at the beginning of the fermentation. Thereafter, W. confusa, Lactobacillus helsingborgensis and Bifidobacterium asteroides appeared and quickly prevailed. In the inoculated silage, Lactobacillus plantarum dominated the whole ensiling process. The genus Clostridium dominated the clostridial community, and was depressed with the inoculated treatment. Clostridium perfringens, Garciella sp. and Clostridium baratii were the main initiators of the clostridial fermentation of the control silage, while Clostridium tyrobutyricum became the most abundant Clostridia with prolonged ensiling. Overall in the inoculated silage, little changes in the clostridial community were observed throughout the ensiling period. Treating alfalfa silage with a homolactic acid-based bacterial inoculant prevented a clostridial fermentation resulting in more efficient fermentation.

CONCLUSION

Distinct changes in the bacterial community with a special focus on the clostridial community were associated with the development of the clostridial fermentation during the ensiling of alfalfa.

SIGNIFICANCE AND IMPACT OF THE STUDY

High-throughput sequencing based on a novel Clostridia-specific primer set proved a potentially useful tool to study the clostridial community dynamics, and could aid to elucidate the mechanism by which the clostridial fermentation develops during the ensiling of alfalfa.

Measurement of systemic oxygen delivery and inotropy in healthy term neonates with the Ultrasonic Cardiac Output Monitor (USCOM)

INTRODUCTION

The aim of this study was to assess the normal values for Smith-Madigan inotropy (SMI), Smith-Madigan inotropy index (SMII), oxygen delivery (DO2) and oxygen delivery index DO2I in healthy term neonates on the first day of life and during circulatory adaptation over the first three days of life.

METHODS

Hemodynamics of the left heart were measured non-invasively in 71 normal full-term neonates over the first three days using the Ultrasonic Cardiac Output Monitor (USCOM). This was combined with hemoglobin concentration from umbilical cord blood and pulse oximetry to calculate DO2 and DO2I. Blood pressure was measured using automated oscillometry and combined with the hemodynamic measures and hemoglobin concentration using the Smith-Madigan method to calculate inotropy (SMI) and inotropy index (SMII).

RESULTS

SMI and SMII showed no significant change during the study period, ranging from 154 to 168 mW and 694 to 731 mW/m(2). Mean (SD) DO2 and DO2I showed a significant fall over three days from 131 (63) ml/min and 596 (278) ml/m(2)/min to 118 (46) ml/min and 517 (173) ml/m(2)/min (p<0.01 and <0.001 respectively) with a corresponding decrease in cardiac output from 758 (143) ml/min to 658 (131) ml/min, (p=0.002). There was no significant change in stroke volume, heart rate, SMI or SMII within the first day. DO2 and DO2I showed small but significant decreases within the first day from 153 (46) ml/min and 699 (174) ml/min/m(2) to 129 (36) ml/min and 609 (141) ml/min/m(2) (p=0.017 and 0.048 respectively).

CONCLUSIONS

Normal inotropy of the left heart and systemic DO2 values in healthy full-term neonates over the first three days of life were assessed using the USCOM. Subjects showed stable myocardial contractility over the first three days with decreasing DO2 and DO2I in line with the decrease in cardiac output (CO). DO2 and DO2I showed small but significant reductions during the first 24 h. USCOM proved to be a feasible and convenient non-invasive bedside tool to assess inotropy and oxygen delivery in neonates.