Risk factors for pneumothorax associated with isolated congenital diaphragmatic hernia: results of a Japanese multicenter study

Intraoperative surgical complications of open surgery for congenital diaphragmatic hernia: a multicenter, observational study in Japan

PURPOSE

This study aimed to clarify surgical complications associated with open surgery for congenital diaphragmatic hernia (CDH).

METHODS

We performed an exploratory data analysis of the clinical characteristics of surgical complications of neonates with CDH who underwent laparotomy or thoracotomy between 2006 and 2021. Data of these patients were obtained from the database of the Japanese CDH Study Group.

RESULTS

Among 1,111 neonates with left or right CDH, 852 underwent open surgery (laparotomy or thoracotomy). Of these 852 neonates, 51 had the following surgical complications: organ injury (n = 48; 6% of open surgeries); circulatory failure caused by changes in the organ location (n = 2); and skin burns (n = 1). Injured organs included the spleen (n = 30; 62% of organ injuries), liver (n = 7), lungs (n = 4), intestine (n = 4), adrenal gland (n = 2), and thoracic wall (n = 2). Fourteen of the patients who experienced organ injury required a blood transfusion (2% of open surgeries). The adjusted odds ratio of splenic injury for patients with non-direct closure of the diaphragm was 2.2 (95% confidence interval, 1.1-4.9).

CONCLUSION

Of the patients who underwent open surgery for CDH, 2% experienced organ injury that required a blood transfusion. Non-direct closure of the diaphragmatic defect was a risk factor for splenic injury.

Risk Factors for Preoperative Pneumothorax in Neonates With Isolated Left-Sided Congenital Diaphragmatic Hernia: An International Cohort Study

BACKGROUND

We aimed to investigate the clinical characteristics and outcomes of patients with isolated left-sided congenital diaphragmatic hernia (CDH) who developed preoperative pneumothorax and determine its risk factors.

METHODS

We performed an international cohort study of patients with CDH enrolled in the Congenital Diaphragmatic Hernia Study Group registry between January 2015 and December 2020. The main outcomes assessed included survival to hospital discharge and preoperative pneumothorax development. The cumulative incidence of pneumothorax was estimated by the Gray test. The Fine and Gray competing risk regression model was used to identify the risk factors for pneumothorax.

RESULTS

Data for 2858 neonates with isolated left-sided CDH were extracted; 224 (7.8%) developed preoperative pneumothorax. Among patients with a large diaphragmatic defect, those with pneumothorax had a significantly lower rate of survival to discharge than did those without. The competing risks model demonstrated that a patent ductus arteriosus with a right-to-left shunt flow after birth (hazard ratio [HR]: 1.78; 95% confidence interval [CI]: 1.21-2.63; p = 0.003) and large defects (HR: 1.65; 95% CI: 1.13-2.42; p = 0.01) were associated with an increased risk of preoperative pneumothorax. Significant differences were observed in the cumulative incidence of pneumothorax depending on defect size and shunt direction (p < 0.001).

CONCLUSIONS

Pneumothorax is a significant preoperative complication associated with increased mortality in neonates with CDH, particularly in cases with large defects. Large diaphragmatic defects and persistent pulmonary hypertension were found to be risk factors for preoperative pneumothorax development.

LEVEL OF EVIDENCE

LEVEL Ⅲ Retrospective Comparative Study.

Post-natal prognostic factors in CDH: experience of 11 years in a referral center in Brazil

OBJECTIVE

To describe post-natal risk factors associated with death in Newborns (NB) with Congenital Diaphragmatic Hernia (CDH) in a Brazilian reference center.

METHODS

In this retrospective cohort study, post-natal clinical factors of all NB diagnosed with CDH were reviewed in an 11-year period (2007‒2018). The primary outcome was death. Secondary outcomes included clinical features, prognostic indexes, type of mechanical ventilation, complications during hospitalization and surgical repair.

RESULTS

After applying the exclusion criteria, the authors analyzed 137 charts. Overall mortality was 59% (81/137), and the highest rates were observed for low-birth-weight NB (87%), syndromic phenotype (92%), and those with major malformations (100%). Prognostic indexes such as Apgar, SNAPPE-II and 24hOI (best oxygenation index in 24 hours) were all associated with poor evolution. In a multivariate analysis, only birth weight and 24hOI were statistically significant risk factors for mortality, with a reduction in mortality risk of 17.1% (OR = 0.829, 95% IC 0.72‒0.955, p = 0.009) for each additional 100g at birth and an increase by 26.5% (OR = 1.265, 95% IC 1.113‒1.436, p = 0.0003) for each unitary increase at the 24hOI.

CONCLUSION

Prognostic indexes are an important tool for predicting outcomes and improving resource allocation. Post-natal risk factors may be more suitable for settings where antenatal diagnosis is not universal. Classical risk factors, such as prematurity, low birth weight, higher need for supportive care, and poorer prognostic indexes were associated with mortality in our CDH population.

Neonatal pneumothorax in congenital diaphragmatic hernia: Be wary of high ventilatory pressures

Background

Patients with congenital diaphragmatic hernia (CDH) require invasive respiratory support and higher ventilator pressures may be associated with barotrauma. We sought to evaluate the risk factors associated with pneumothorax in CDH neonates prior to repair.

Methods

We retrospectively reviewed newborns born with CDH between 2014 and 2019 who developed a pneumothorax, and we matched these cases to patients with CDH without pneumothorax.

Results

Twenty-six patients were included (n=13 per group). The pneumothorax group required extracorporeal life support (ECLS) more frequently (85% vs 54%, p=0.04), particularly among type A/B defects (31% vs 7%, p=0.01). The pneumothorax group had higher positive end-expiratory pressure (PEEP) within 1 hour of birth (p=0.02), at pneumothorax diagnosis (p=0.003), and at ECLS (p=0.02). The pneumothorax group had a higher mean airway pressure (Paw) at birth (p=0.01), within 1 hour of birth (p=0.01), and at pneumothorax diagnosis (p=0.04). Using multiple logistic regression with cluster robust SEs, higher Paw (OR 2.2, 95% CI 1.08 to 3.72, p=0.03) and PEEP (OR 1.8, 95% CI 1.15 to 3.14, p=0.007) were associated with an increased risk of developing pneumothorax. There was no difference in survival (p=0.09).

Conclusions

Development of a pneumothorax in CDH neonates is independently associated with higher Paw and higher PEEP. A pneumothorax increases the likelihood of treated with ECLS, even with smaller defect.

High-frequency ventilation in preterm infants and neonates

High-frequency ventilation (HFV) has been used as a respiratory support mode for neonates for over 30 years. HFV is characterized by delivering tidal volumes close to or less than the anatomical dead space. Both animal and clinical studies have shown that HFV can effectively restore lung function, and potentially limit ventilator-induced lung injury, which is considered an important risk factor for developing bronchopulmonary dysplasia (BPD). Knowledge of how HFV works, how it influences cardiorespiratory physiology, and how to apply it in daily clinical practice has proven to be essential for its optimal and safe use. We will present important aspects of gas exchange, lung-protective concepts, clinical use, and possible adverse effects of HFV. We also discuss the study results on the use of HFV in respiratory distress syndrome in preterm infants and respiratory failure in term neonates. IMPACT: Knowledge of how HFV works, how it influences cardiorespiratory physiology, and how to apply it in daily clinical practice has proven to be essential for its optimal and safe use. Therefore, we present important aspects of gas exchange, lung-protective concepts, clinical use, and possible adverse effects of HFV. The use of HFV in daily clinical practice in lung recruitment, determination of the optimal continuous distending pressure and frequency, and typical side effects of HFV are discussed. We also present study results on the use of HFV in respiratory distress syndrome in preterm infants and respiratory failure in term neonates.