An abrupt increment in the respiratory rate is a sign of neonatal pneumothorax

Risk Factors and Outcomes Associated with Pneumothorax in Very Preterm Infants

BACKGROUND/OBJECTIVES

Pneumothorax can be a major complication of neonatal lung diseases. We aim to delineate trends and describe the main outcomes related to pneumothorax in very preterm infants (VPI).

METHODS

Preterm infants < 32 weeks of gestation admitted in two-level III neonatal intensive care units (1995-2019) were included. Risk factors and outcomes were assessed by logistic regression and adjusted for gestational age (GA).

RESULTS

In total, 4271 VPI with a mean GA of 28.7 ± 2.3 weeks were evaluated. Pneumothorax was diagnosed in 174 patients (4.1%, 95% Confidence Interval (CI) 3.5-4.7) with its incidence inversely proportional to GA: 9.9% in 23-25 w and 2.1% in 30-31 w (p < 0.001), but stable over the years 1995-1999 (5.2%) and 2015-2019 (4.2%) (p = 0.309). Patients with pneumothorax exhibited higher rates of severe intraventricular hemorrhage (IVH) (Odds Ratio (OR) = 2.0 (95%CI 1.3-3.1), p = 0.003), bronchopulmonary dysplasia (OR = 2.7 (95%CI 1.7-4.4), p < 0.001), and death (OR = 8.5 (95%CI 6.2-11.6), p < 0.001). Independent risk factors for pneumothorax were GA, prolonged premature rupture of membranes, and intubation in the delivery room. The composite outcome of death or severe IVH was higher in patients with pneumothorax with an adjusted OR = 6.7 (95%CI 4.7-9.6), p < 0.001. Although VPI mortality has significantly decreased over the years (20.3% 1995-1999 and 11.7% 2015-2019, p < 0.001), we found no significant difference in pneumothorax-related deaths.

CONCLUSION

Pneumothorax remains a serious threat to VPI, leading to a higher incidence of morbidity, and mortality attributable to this complication has not decreased. Preventive strategies and early recognition are essential for improving disability-free survival in VPI.

Risk Factors for Pneumothorax and Its Association with Ventilation in Neonates

OBJECTIVE

The mode of ventilation that is implicated in pneumothorax is the one at the time of its diagnosis. Although there is evidence that air leak starts many hours before it is clinically evident, there are no prior studies that have investigated the association of pneumothorax with the mode of ventilation few hours before rather than at the time of its diagnosis.

STUDY DESIGN

A retrospective case-control study was conducted in the neonatal intensive care unit (NICU) between 2006 and 2016 where cases of neonates with pneumothorax were compared with gestational age-matched control neonates without pneumothorax. Respiratory support associated with pneumothorax was classified as the mode of ventilation 6 hours before the clinical diagnosis of pneumothorax. We investigated the factors that were different between cases and controls, and between cases of pneumothorax on bubble continuous positive airway pressure (bCPAP) and invasive mechanical ventilation (IMV).

RESULT

Of the 8,029 neonates admitted in the NICU during the study period, 223 (2.8%) developed pneumothorax. Among these, 127 occurred among 2,980 (4.3%) neonates on bCPAP, 38 among 809 (4.7%) neonates on IMV, and the remaining 58 among 4,240 (1.3%) neonates on room air. Those with pneumothorax were more likely to be male, have higher body weight, require respiratory support and surfactant administration, and have bronchopulmonary dysplasia (BPD). Among those who developed pneumothorax, there were differences in the gestational age, gender, and use of antenatal steroids between those who were on bCPAP as compared to those on IMV. IMV was associated with increased odds of pneumothorax as compared to those on bCPAP in a multivariable regression analysis. Cases on IMV had higher incidence of intraventricular hemorrhage, retinopathy of prematurity, BPD, and necrotizing enterocolitis, as well as longer length of stay as compared to those on bCPAP.

CONCLUSION

Neonates who require any respiratory support have higher incidence of pneumothorax. Among those on respiratory support, those on IMV had higher odds of pneumothorax and worse clinical outcomes as compared to those on bCPAP.

KEY POINTS

· The process of air leak leading to pneumothorax in majority of neonates starts much before it is clinically diagnosed.. · It is possible to detect the air leak early in the process by subtle changes in the signs, symptoms and changes in lung function.. · True association of the ventilation associated with pneumothorax is not at the time of diagnosis of pneumothorax but few hours before it is diagnosed.. · There is higher incidence of pneumothorax in neonates on any respiratory support.. · There is significantly higher incidence of pneumothorax among neonates on invasive ventilations as compared to noninvasive ventilation after correction for all other clinical factors..

Review of risk factors, clinical manifestations, rapid diagnosis, and emergency treatment of neonatal perioperative pneumothorax

Perioperative neonatal pneumothorax (NP) is rare but very fatal. Most of the surgeries and treatments in the neonatal period are time-limited or emergent, and there are often some risk factors for pneumothorax before surgery. Physicians, surgeons and anesthesiologists need to identify possible risk factors for pneumothorax before surgery in preterm babies, patients receiving mechanical ventilation and those with underlying lung disease. The clinical presentation of NP is nonspecific, and patients may rapidly develop life-threatening complications if not promptly diagnosed and managed. This review highlights recent progress in the identification of risk factors, clinical manifestations, diagnosis and management of NP during the perioperative period.

Pneumothorax prevalence and mortality per gestational age in the newborn

OBJECTIVES

Pneumothorax (PTX) in newborns is a life-threatening condition associated with high morbidity and mortality especially in premature infants. The frequency of PTX in neonates at different gestational ages (GA) and its impact on neonatal mortality have not been quantified. We aimed to determine: (1) the prevalence of PTX in neonates at different GA from ≤24 to ≥37 weeks, (2) the impact of PTX on mortality per GA, and (3) the impact of PTX on the length of stay (LOS) per GA.

METHODS

The national Kids' Inpatient Database for the years of 2006-2012 were used. We included all infants admitted to the hospital with a documented GA and International Classification of Disease 9 code of PTX. Bivariate and multivariate analyses were conducted and odds ratios (OR) were calculated.

RESULTS

A total of 10,625,036 infants were included; of them 3665 infants (0.034%) had a diagnosis of PTX, with highest prevalence at ≤24 weeks GA (0.67%), and lowest at term (0.02%). The overall mortality rate of patients with PTX was 8.8%, and greater in preterm (16.3%) versus term infants (2.7%). The association of mortality with PTX was greatest at GA of 29-32 weeks (OR = 8.55; 95% confidence interval: 6.56-11.13). Infants who survived until discharge had a median of 2-12 days longer LOS depending on GA category.

CONCLUSIONS

The prevalence of PTX peaks in infants less than 24 weeks, however, its impact on mortality is greatest at 29-32 weeks. PTX is associated with longer LOS in survivors.