Tachypnea in response to hypoxemia decreases with age in older patients.

AIM: To investigate if tachypneic response to hypoxia is decreased in older patients. METHODS: We included all patients ≥65 years of age attending 52 Spanish emergency departments (EDs) for whom peripheral arterial oxygen saturation (SatO2) measured by pulsioxymetry and respiratory rate (RR) were registered at ED arrival. We assessed the relationship between SatO2 and RR in different models, and with the best-fitting model, we independently analyzed this relationship in four subgroups according to patient age (65-69, 70-79, 80-89, and ≥90 years). Five sensitivity analyses using different subsets of patients were carried out to check for the consistency of the results. RESULTS: We included 7126 patients, with medians for SatO2 and RR of 97% (interquartile range [IQR]: 94-98) and 15 bpm (IQR: 15-16), respectively. We found significant associations (P < 0.001) between SatO2 and RR in every model tested (P < 0.001 for all), with the quadratic model obtaining the best fit (R2: 0.098) over those obtained with linear (R2: 0.096) and logarithmic (R2: 0.092) models. The same was observed in sensitivity analyses, with R2 for quadratic models ranging from 0.069 in patients with low comorbidity and 0.102 in patients breathing room air. The mean RR for 100% SatO2 was 15 bpm and increased as SatO2 decreased, although with a progressive slowing of the slope, with a mean RR of 27 at 50% SatO2. We detected a decreased RR response to increasing hypoxemia according to age and, while the RR curve was higher and with a progressively steepening slope in the 972 patients aged 65-69 (mean RR of 42 bpm with 50% SatO2), a progressive slowing of slope was observed in the 2693 patients aged 70-79 (mean RR of 28 with 50% SatO2), the 2582 aged 80-89 (mean RR of 25) and the 879 aged ≥90 (mean RR of 23). Sensitivity analyses provided very similar results. CONCLUSION: Tachypneic response to hypoxemia in older patients decreases as age advances, regardless of the reason leading to hypoxemia. Geriatr Gerontol Int 2024; ••: ••-••.

Diagnosis and Management of an H-type Tracheoesophageal Fistula in a Neonate: A Case Report.

Tracheoesophageal fistula (TEF) is a congenital anomaly resulting from the incomplete fusion of the tracheoesophageal ridge during the third week of embryonic development. This case report presents a male neonate, born at term via normal vaginal delivery, who developed respiratory distress, persistent cough, and vomiting within hours of birth. Despite initial management with respiratory support and antibiotics, the infant's condition persisted, prompting further investigation. High-resolution computed tomography and an esophagogram revealed a suspected H-type TEF, which was confirmed via rigid bronchoscopy. Following the diagnosis, the patient underwent corrective surgery, leading to symptom resolution. This case underscores the importance of considering TEF in neonates with persistent respiratory symptoms and the need for a combination of diagnostic modalities to confirm this rare anomaly. Prompt surgical intervention is crucial to prevent complications and improve outcomes.

A case report of cardiopulmonary exercise testing and incentive spirometry-guided breathing pattern alteration for a severely tachypnoeic kyphoscoliotic patient undergoing major thoracic surgery for suspected lung malignancy.

A case report of a severely dyspnoeic kyphoscoliotic patient intended for an elective major thoracic surgery for suspected lung malignancy. With baseline near maximal breathing frequency and shallow breaths and poor lung mechanics, the first encountered anaesthetist considered this patient too high risk for lobectomy. This case illustrated the application of cardiopulmonary exercise testing to provide an objective assessment of the patient's functional capacity, ventilatory efficiency and delineation of modifiable respiratory components that guide the formulation of individualized prehabilitation programme. It also depicted the perioperative role of an off-label use of incentive spirometry in providing visual feedbacks and led to subsequent assessment breathing pattern alternation. Patient underwent the lung resection uneventfully and returned to normal lifestyle on postoperative day 4.

Can I Discharge This Adult Patient with Abnormal Vital Signs From the Emergency Department?

BACKGROUND: Vital signs are an essential component of the emergency department (ED) assessment. Vital sign abnormalities are associated with adverse events in the ED setting and may indicate a risk of poor outcomes after ED discharge. CLINICAL QUESTION: What is the risk of adverse events among adult patients with abnormal vital signs at the time of ED discharge? EVIDENCE REVIEW: Studies retrieved included 6 retrospective studies with adult patients discharged from the ED. These studies evaluated adverse outcomes in adult patients discharged from the ED with abnormal vital signs. Hypotension at discharge was associated with the highest odds of adverse events after discharge. Tachycardia was also a key predictor of adverse events after discharge and may be easily missed by ED clinicians. CONCLUSION: Based on the available evidence, the specific vital sign abnormality and the number of total abnormalities influence the risk of adverse outcomes after discharge. Vital sign abnormalities at the time of discharge also increase the risk of ED revisit. The most common abnormal vital sign at the time of discharge is tachycardia.

Caesarean section and respiratory system disorders in newborns.

Cesarean section (C-section) delivery is associated with a higher risk of respiratory problems in newborns, particularly if performed electively at 37 weeks. This risk is greater than with spontaneous or induced labor but diminishes as gestation advances. To lower the incidence of respiratory issues in newborns, it is vital to promote natural labor, avoid unnecessary C-sections, and offer thorough prenatal care. Healthcare providers and expectant mothers should assess the risks and benefits of elective C-sections carefully. By advocating for natural labor and reducing unnecessary C-sections, the occurrence of respiratory problems in newborns can be decreased. Adequate prenatal care and monitoring are crucial for identifying and managing potential risk factors for respiratory diseases in newborns. It is crucial for healthcare professionals to educate expectant mothers about the risks of elective C-sections and the advantages of allowing labor to progress naturally. By fostering transparent communication and collaborative decision-making between healthcare providers and pregnant women, well-informed choices can be made that prioritize the health of both the mother and the baby. Furthermore, ongoing research and advancements in medical technology can improve our understanding of how delivery methods affect newborn respiratory health, ultimately leading to better outcomes and care practices in the future.

Exercise intolerance and oxygen dynamics in nontuberculous mycobacteria with bronchiectasis.

BACKGROUND: Nontuberculous mycobacterial pulmonary disease (NTM-PD) patients often have exercise intolerance. Pulmonary rehabilitation (PR) to improve such patients' conditions is often not based on its exercise pathophysiology. We have reported that the oxygen consumption (ΔFO2) by expiratory gas analysis, i.e., the inspired-expired-expiratory mean oxygen concentration difference, is related to the minute ventilation-carbon dioxide output (V'E-V'CO2)-slope and oxygen uptake (V'O2) independent of the V'E. The aim of this study was to investigate how ΔFO2 is related to dynamic ventilatory variables, chest computed tomography (CT), and echocardiography findings in NTM-PD patients to understand their pathophysiological conditions. METHODS: Clinical data of NTM-PD patients with exertional dyspnea (n = 29) who underwent incremental exercise testing, chest CT, and echocardiography at the same time were compared with those of control participants (n = 12). RESULTS: In the NTM-PD group, 1) peak V'O2 decreased (NTM-PD: 17.6 vs. controls: 28.7 mL⋅min-1⋅kg-1), and 2) ΔFO2 at peak exercise was negatively correlated with respiratory frequency at peak exercise (correlation coefficient: r = -0.80, p < 0.0001), V'E-V'CO2-slope (r = -0.75, p < 0.0001), bronchiectasis CT score (r = -0.52, p = 0.0042), and the trans-tricuspid pressure gradient (r = -0.39, p = 0.0417), and positively correlated with peak V'O2 (r = 0.71, p < 0.0001) and the body mass index (r = 0.42, p = 0.0217), but it was not correlated with V'E at peak exercise and the cavity CT score. CONCLUSIONS: Exertional oxygen consumption, independent of ventilatory ability, is associated with exercise tolerance and ventilatory efficiency, while being related to tachypnea and bronchiectasis rather than cavitation in NTM-PD patients. These findings may be useful in considering exercise physiology-based PR for NTM-PD patients with exertional dyspnea.

Spontaneous Coronary Artery Dissection in the Late Third Trimester of Pregnancy.

Acute coronary syndrome due to a non-atherosclerotic, non-traumatic, or iatrogenic-induced spontaneous coronary artery dissection (SCAD) is a rare clinical condition that affects mostly young women of reproductive age. In this case, we present a 36-week-pregnant, 35-year-old G2P1 woman, with no previous medical history, who was admitted to our hospital with premature pre-labor contractions. During her hospitalization, she underwent a coronary artery percutaneous angiography revealing SCAD of the three coronary vessels, after an episode of acute-onset chest pain, tachypnea, EKG alterations, cardiac enzyme elevation, and bilateral pleural effusions. An emergency cesarean delivery was performed and the patient was transferred to the cardiology intensive care unit. Conservative management was decided and the woman was discharged a few days later.

Evaluation of vitamin D in the diagnosis of infants with respiratory distress, the clinical value: A systematic review and meta-analysis.

INTRODUCTION: Respiratory distress (RD) is the most common cause of admission to the Neonatal Intensive Care Unit (NICU). The role of Vitamin D in the development and fortification of fetal pulmonary architecture and the synthesis of surfactants is well-documented. While different serum levels of 25-hydroxyvitamin D (Vit. D) have been studied for their diagnostic significance in RD, there is limited research on how it specifically affects the development of respiratory problems in infants and their mothers. The purpose of the present study is a systematic review and meta-analysis to evaluate the correlation between serum levels of Vit. D in mothers and newborns with RD, and to determine the impact of treating either population on the clinical outcomes of afflicted infants. METHODS: A comprehensive literature search was conducted across various databases, including PubMed, ScienceDirect, Cochrane Library, ISI, and Google Scholar, using a combination of keywords such as RD, diagnosis, vitamin D, mothers, infants, vitamin D supplementation, Respiratory distress syndrome(RDS), and Transient Tachypnea of Newborn (TTN). The search was carried out until March 2024.The level of vitamin D in both mothers and their infants was systematically extracted and analyzed to determine the diagnostic efficacy of Vit. D levels. The mean difference (MD) was calculated along with a 95% confidence interval to determine the association between the Vit. D levels in newborns and their mothers and the likelihood of RD, RDS and TTN in infants. To assess potential publication bias, a funnel plot was generated and Egger's regression test was applied, utilizing a random-effects model. RESULTS: Initially a total of 298 relevant articles was retrieved. Among them, 17 articles with a total of 1,582 infants (745 cases and 837 healthy controls) met the criteria as eligible studies. Of these six were prospective cohort studies, four retrospective case-control studies, four randomized controlled trials (RCTs), and three descriptive-analytical studies. The meta-results revealed a significant association between Vit. D levels and risk of RD in infants (MD = 6.240, 95 %CI: 4.840-7.840, P < 0.001) and mothers (MD = 8.053, 95 %CI: 4.920-11.186, P < 0.001). Furthermore, a strong association was found for risk of RDS (MD = 5.493, 95 %CI: 3.356-7.631, P < 0.001) in infants and TTN (MD = 6.672, 95 %CI: 4.072-9.272, P < 0.001), (MD = 8.595, 95%CI: 4.604-12.586, P < 0.001) both in infants and mothers. Administering 50,000 units of vitamin D to mothers (MD = 8.595, 95 %CI: 4.604-12.586, P < 0.001) prior to childbirth was observed to reduce the likelihood of RD in newborns by 64 % (RR = 0.36, 95 %CI: 0.23-0.57, P < 0.001). Supplemental vitamin D provided to infants was associated with several clinical benefits. CONCLUSION: Our meta-results indicated a significant correlation between serum levels of Vit. D and the risk of RD, RDS and TTN in infants. Prophylactic maternal administration of vitamin D plays a protective role against neonatal RD. Additionally, providing vitamin D to premature infants has shown a significant impact in reducing the incidence of respiratory complications.

Left atrial strain assessment unveils left ventricular diastolic dysfunction in neonates with transient tachypnea of the newborn: A prospective observational study.

INTRODUCTION: An inadequate clearance of lung fluid plays a key role in the pathogenesis of transient tachypnea of the newborn (TTN). OBJECTIVES: To evaluate if left ventricular diastolic dysfunction contributes to reduced clearance of lung fluid in TTN. MATERIALS AND METHODS: This was a prospective, observational study. Echocardiography and lung ultrasound were performed at 2, 24 and 48 h of life (HoL) to assess biventricular function and calculate lung ultrasound score (LUS). Left atrial strain reservoir (LASr) provided surrogate measurement of left ventricular diastolic function. RESULTS: Twenty-seven neonates with TTN were compared with 27 controls with no difference in gestation (36.1 ± 2 vs. 36.9 ± 2 weeks) or birthweight (2508 ± 667 vs. 2718 ± 590 g). Biventricular systolic function was normal in both groups. LASr was significantly lower in cases at 2 (21.0 ± 2.7 vs. 38.1 ± 4.4; p < 0.01), 24 (25.2 ± 4.5 vs. 40.6 ± 4.0; p < 0.01) and 48 HoL (36.5 ± 5.8 and 41.6 ± 5.2; p < 0.01), resulting in a significant group by time interaction (p < 0.001), after adjusting for LUS and gestational diabetes. A logistic regression model including LUS, birth weight and gestational diabetes as covariates, showed that LASr at 2 HoL was a predictor of respiratory support at 24 HoL, with an adjusted odds ratio of 0.60 (CI 0.36-0.99). CONCLUSIONS: LASr was reduced in neonates with TTN, suggesting diastolic dysfunction, that may contribute to the delay in lung fluid clearance.

Mycoplasma spp. pneumonia and subsequent pulmonary hypertension in a domestic ferret (Mustela putorius furo).

Treatment of Mycoplasma spp. pneumonia has rarely been described in domestic ferrets (Mustela putorius furo). A 10-month-old, 0.53 kg, female spayed domestic ferret was presented for oxygen-dependent, chronic dyspnea of one-month's duration. Physical examination findings included dyspnea, tachypnea, increased bronchovesicular sounds bilaterally, and an intermittent non-productive cough. Bloodwork abnormalities included a mild leukocytosis (8.6×103/µL), mild neutrophilia (4.0×103/µL), mild hypoalbuminemia (2.7 g/dL), mild hyperglobulinemia (3.3 g/dL), mild hyponatremia (147 mEq/L), and mild hypochloremia (111.4 mEq/L). Radiographs revealed a marked diffuse bronchial pattern with peribronchial cuffing, a mild main pulmonary artery bulge, distended caudal lobar pulmonary arteries, and decreased serosal detail within the abdomen. An echocardiogram revealed indications of moderate pulmonary hypertension and systolic anterior motion of the mitral valve. Polymerase chain reaction testing for Mycoplasma spp. was positive, and treatment was initiated with doxycycline (10 mg/kg PO q 12 h for 16 weeks), prednisolone (0.4 mg/kg PO q 12 h for 13 weeks, tapered to 0.2 mg/kg PO q 12 h for two weeks, then eventually increased to 0.7 mg/kg PO q 12 h until further notice), sildenafil (0.3 mg/kg PO q 24 h for 13 weeks), and oxygen supplementation via an oxygen cage for six weeks. On repeat echocardiogram eleven weeks after initiation of doxycycline therapy, the pulmonary hypertension had resolved. At follow up six months later, the ferret was stable on previously prescribed medications and did not require oxygen supplementation. Mycoplasma spp. and pulmonary hypertension should be considered in cases of respiratory distress in ferrets.

Serum biomarkers in neuroendocrine cell hyperplasia of infancy.

BACKGROUND: Neuroendocrine cell hyperplasia of infancy (NEHI) is a form of childhood interstitial lung disease of unknown origin associated with hyperplasia of pulmonary neuroendocrine cells (PNECs). Diagnosis is based on the characteristic clinical picture and typical radiological imaging, and, in some cases, on lung biopsies. To date, no biochemical indicators of the disease have been identified. AIM: We aimed to determine biomarkers that could be useful in the management of children diagnosed with NEHI. METHODS: Patients with NEHI and healthy children were enrolled. Concentrations of serum biomarkers secreted by PNECs (calcitonin gene-related peptide and gastrin-releasing peptide) and biomarkers of the destruction of alveolar capillary membrane (surfactant proteins A and D [SP-A and SP-D]; glycoprotein Krebs von den Lungen-6 [KL-6]; metalloproteinases 7 and 9 [MMP-7 and MMP-9]; tissue inhibitor of metalloprotease 1) were measured. RESULTS: Fifty-two children with NEHI and 23 healthy children were included in the study. The median age of children with NEHI was 3.9 years. There were no differences in serum levels of biomarkers secreted by PNECs between groups. KL-6 levels were significantly higher in children with NEHI than in healthy ones (median 119.6 vs. 92.1 U/mL, p = 0.003); however, concentrations of KL-6 were low in both groups. No significant differences existed between groups for the remaining biomarkers associated with the destruction of the alveolar-capillary membrane. CONCLUSIONS: Measurement of serum biomarkers released by PNECs and those associated with the destruction of the alveolar-capillary membrane does not appear to be useful in the management of children with NEHI.

Neonatal respiratory complications in twins at 36-38 weeks of gestation.

BACKGROUND: Twin pregnancies are associated with a high risk of perinatal mortality and morbidity. Late preterm or early term delivery is frequently performed to avoid unexpected fetal death in uncomplicated twin pregnancies. Nonetheless, delivery before full term is associated with neonatal respiratory complications. This study aimed to evaluate perinatal respiratory complications in twins delivered between 36 and 38 weeks of gestation. METHODS: A retrospective cohort study was conducted on twins delivered between 36 and 38 weeks of gestation from January 2008 to June 2020. The primary outcomes were the incidence of composite neonatal respiratory morbidity, which included respiratory distress syndrome, transient tachypnea of the newborn, meconium aspiration syndrome, mechanical ventilation or continuous positive airway pressure according to gestational age at delivery, and chorionicity. The relationship between gestational age at delivery and composite neonatal respiratory morbidity was evaluated using multivariate logistic regression analysis adjusted for potential confounders. RESULTS: This study included 1608 twins (614 monochorionic diamniotic twins, 994 dichorionic diamniotic twins). At 36, 37, and 38 weeks of gestation, the frequencies of composite neonatal respiratory morbidity were 19.4%, 10.7%, and 9.2% in dichorionic diamniotic twins and 13.6%, 8.7%, and 9.4% in monochorionic diamniotic twins, respectively. In dichorionic diamniotic twins, the composite neonatal respiratory morbidity rate was higher for twins delivered at 36 weeks of gestation than for those delivered at 37 weeks. No significant differences between monochorionic diamniotic twins were detected. CONCLUSIONS: In uncomplicated dichorionic diamniotic twin pregnancies, delivery should be considered after 37 weeks of gestation to reduce neonatal respiratory complications.

Risk of Transient Tachypnea of the Newborn following Elective Cesarean Section Increases at a Gestational Age of 37 Weeks Compared to That at ≥ 38 Weeks Despite the Exclusion of Pre-Existing Risk Factors for Neonatal Respiratory Disorders.

Background: Elective cesarean sections (ECSs) for early-term pregnancies at 37 weeks of gestational age (GA) aim to reduce the risk of emergency cesarean sections due to the onset of labor or rupture of membranes. However, resultant increases in neonatal respiratory disorders, including transient tachypnea of the newborn (TTN) have been observed. However, few studies have elucidated the associated risk factors. Consequently, we aimed to determine whether differences existed in the clinical outcomes between neonates delivered via ECS at 37 weeks and those delivered at ≥ 38 weeks of GA. Methods: A retrospective analysis was conducted on 259 neonates born via ECS at Tottori University Hospital, between January 2013 and December 2019, with birthweights ≥ 2500 g and GAs > 37 weeks. The neonates were categorized into two cohorts: births at 37 and at ≥ 38 weeks of GA (37-week and 38-week cohorts). The principal clinical outcomes included the appearance, pulse, grimace, activity, and respiration (Apgar) scores, need for positive-pressure ventilation, incidence of TTN, and length of hospital stay. Results: No statistically significant differences were observed in the indications for ECS, sex, or birthweight between the two cohorts. The 37-week cohort exhibited a lower 1-min Apgar score than did the 38-week cohort, with no statistically significant differences between the two cohorts, at 5 min. Statistically significant differences were not observed in the need for positive-pressure ventilation during initial resuscitation or length of hospital stay for patients with TTN between the two cohorts. Notably, the 37-week cohort exhibited a significantly higher incidence of TTN than did the 38-week cohort. Conclusion: ECSs at 37 weeks of GA exhibited an increased risk of TTN than ECSs at ≥ 38 weeks of GA. Strategic neonatal care and adequate preparation can mitigate this risk without affecting the length of hospital stay.

A Case Report of Acute Saddle Pulmonary Embolism in Prader-Willi Syndrome.

Prader-Willi syndrome (PWS) is an exceedingly rare congenital syndrome of chromosome 15 that presents multiple comorbidities in said individuals. The associated quality of life for those with the disease is often severely diminished; more tragically, mortality associated with the disease is also increased. Pulmonary embolism (PE) is highly associated with mortality and has been shown to be more prevalent in patients with PWS. This case report details a patient with PWS who survived an acute saddle PE and looks to bring more clinical knowledge that can be applied when dealing with individuals with PWS.

Safety and Efficacy of 2.5 mg and 1.25 mg Nebulized Salbutamol Compared with Placebo on Transient Tachypnea of the Newborns: A Triple-Blind Phase II/III Parallel Randomized Controlled Trial.

Background: To evaluate the safety and efficacy of 2.5 and 1.25 mg nebulized salbutamol on Transient Tachypnea of the Newborn (TTN) compared with placebo. Methods: We conducted a triple-blind, phase II/III parallel randomized controlled trial in two university-affiliated hospitals with neonatal intensive care units. Newborns with a confirmed diagnosis of TTN, with gestational age >35 weeks and gestational weight >2 kg were included. Cases of asphyxia, meconium aspiration syndrome, and persistent pulmonary hypertension were excluded. Ninety eligible patients were randomly allocated in three intervention groups (2.5 mg salbutamol, 1.25 mg salbutamol, and placebo), and a single-dose nebulized product was prescribed 6 hours after the birth. Safety outcomes included postintervention tachycardia, hyperglycemia, hypokalemia, and changes in blood pressure. To evaluate the efficacy, the duration of postintervention tachypnea, TTN clinical score, and clinical and paraclinical respiratory indices were assessed. Parents, Outcome assessors, and data analyzer were blind to the intervention. Results: There was no adverse reaction, including tachycardia, hypokalemia, and jitteriness. Both groups of salbutamol recipients showed significant improvement regarding respiratory rate, TTN clinical score, and oxygenation indices compared with the placebo (p-values <0.001). Nonstatistically significant higher hospital stay was observed in the placebo group. Single 2.5 mg salbutamol nebulization showed a little better outcome than the dose of 1.25 mg, although we could not find statistical superiority. Conclusion: The newly applied single high dose of 2.5 mg nebulized salbutamol is safe in treating TTN and leads to notable faster improvement of respiratory status without any considerable adverse reaction. Registry code: IRCT20190328043133N1.

Thoracic fluid content (TFC) using electrical cardiometry versus lung ultrasound in the diagnosis of transient tachypnea of newborn.

This study aimed to evaluate TFC by EC versus lung ultrasound (LUS) findings for diagnosing and follow-up of TTN in late preterm and term neonates. This prospective observational study was conducted on 80 neonates with gestational age ≥ 34 weeks. TTN group included 40 neonates diagnosed with TTN, and no lung disease (NLD) group included 40 neonates without respiratory distress. LUS and EC were performed within the first 24 h of life and repeated after 72 h. There was a statistically significant increase in TFC in TTN group on D1 [48.48 ± 4.86 (1 KOhm-1)] compared to NLD group [32.95 ± 4.59 (1 KOhm-1)], and then significant decrease in TFC in D3 [34.90 ± 4.42 (1 KOhm-1)] compared to D1 in the TTN group. There was a significant positive correlation between both TFC and LUS with Downes' score, TTN score, and duration of oxygen therapy in the TTN group.   Conclusion: Both LUS and TFC by EC provide good bedside tools that could help to diagnose and monitor TTN. TFC showed a good correlation with LUS score and degree of respiratory distress. What is Known: • Transient tachypnea of the newborn (TTN) is the most common cause of respiratory distress in newborns. • TTN is a diagnosis of exclusion, there are no specific clinical parameters or biomarker has been identified for TTN. What is New: • Thoracic fluid content (TFC) by electrical cardiometry is a new parameter to evaluate lung fluid volume and could help to diagnose and monitor TTN and correlates with lung ultrasound score.

Influence of the chest wall on respiratory function at birth in near-term lambs.

Airway liquid is cleared into lung tissue after birth, which becomes edematous and forces the chest wall to expand to accommodate both the cleared liquid and incoming air. This study investigated how changing chest wall mechanics affects respiratory function after birth in near-term lambs with different airway liquid volumes. Surgically instrumented near-term lambs (139 ± 2 days) were randomized into Control (n = 7) or Elevated Liquid (EL; n = 6) groups. Control lambs had lung liquid drained to simulate expected volumes following vaginal delivery. EL lambs had airway liquid drained and 30 mL/kg liquid returned to simulate expected airway liquid volumes after elective cesarean section. Lambs were delivered, transferred to a Perspex box, and ventilated (30 min). Pressure in the box was adjusted to apply positive (7-8 cmH2O above atmospheric pressure) or negative (7-8 cmH2O below atmospheric pressure) pressures for 30 min before pressures were reversed. External negative pressures expanded the chest wall, reduced chest wall compliance (CCW) and increased lung compliance (CL) in Control and EL lambs. External positive pressures compressed the chest wall, increased CCW and reduced CL in Control and EL lambs. External negative pressure improved pulmonary oxygen exchange, reducing the alveolar-arterial difference in oxygen (AaDO2) by 69 mmHg (95% CI [13, 125]; P = 0.016) in Control lambs and by 300 mmHg (95% CI [233, 367]; P < 0.001) in EL lambs. In contrast, external positive pressures impaired pulmonary gas exchange, increasing the AaDO2 by 179 mmHg (95% CI [73, 285]; P = 0.002) in Control and by 215 mmHg (95% CI [89, 343]; P < 0.001) in EL lambs. The application of external thoracic pressures influences respiratory function after birth.NEW & NOTEWORTHY This study investigated how changes in chest wall mechanics influence respiratory function after birth. Our data indicate that the application of continuous external subatmospheric pressure greatly improves respiratory function in near-term lambs with respiratory distress, whereas external positive pressures impair respiratory function. Our findings indicate that, during neonatal resuscitation at birth, the forces applied to the chest wall should not be ignored as they can have a major impact on neonatal respiratory function.

Neonatal point-of-care lung ultrasound: what should be known and done out of the NICU?

Lung ultrasound is rapidly becoming a useful tool in the care of neonates: its ease of use, reproducibility, low cost, and negligible side effects make it a very suitable tool for the respiratory care of all neonates. This technique has been extensively studied by different approaches in neonatal intensive care unit (NICU), both for diagnostic and prognostic aims and to guide respiratory treatments. However, many neonates are being born in level I/II hospitals without NICU facilities so all pediatricians, not just neonatal intensivists, should be aware of its potential. This is made possible by the increasing access to ultrasound machines in a modern hospital setting. In this review, we describe the ultrasonographic characteristics of the normal neonatal lung. We also discuss the ultrasound features of main neonatal respiratory diseases: transient tachypnea of the neonate (TTN), respiratory distress syndrome (RDS), meconium aspiration syndrome (MAS), pneumothorax (PNX), pleural effusion (PE), or pneumonia. Finally, we mention two functional approaches to lung ultrasound: 1. The use of lung ultrasound in level I delivery centers as a mean to assess the severity of neonatal respiratory distress and request a transport to a higher degree structure in a timely fashion. 2. The prognostic accuracy of lung ultrasound for early and targeted surfactant replacement. CONCLUSION:  LU is still a useful tool in level I/II neonatal units, both for diagnostic and functional issues. WHAT IS KNOWN: • Neonatal lung ultrasound has been recently introduced in the usual care in many Neonatal Intensive Care Units. WHAT IS NEW: • It also has many advantages in level I/II neonatal units, both for neonatologist or even pediatricians that treat neonates in those sites.

A comparison of 2 doses of antenatal dexamethasone for the prevention of respiratory distress syndrome: an open-label, noninferiority, pragmatic randomized trial.

BACKGROUND: Antenatal corticosteroids have been used for the prevention of respiratory complications, intraventricular hemorrhage, necrotizing enterocolitis, and other adverse neonatal outcomes for over 50 years, with limited evidence about their optimal doses. Higher steroid doses or frequencies of antenatal corticosteroids in preterm newborns pose adverse effects such as prolonged adrenal suppression, negative effects on fetal programming and metabolism, and increased risks of neurodevelopmental and neuropsychological impairments. Conversely, lower doses of antenatal corticosteroids may be an effective alternative to induce fetal lung maturation with less risk to the fetus. Late preterm births represent the largest population of all preterm neonates, with a respiratory distress syndrome risk of 8.83%. Therefore, determining the optimal antenatal corticosteroid dosage is of particular importance for this population. OBJECTIVE: This study aimed to compare the efficacy of 5-mg and 6-mg dexamethasone in preventing neonatal respiratory distress syndrome in women with preterm births at 320 to 366 weeks of gestation. STUDY DESIGN: This was an open-label, randomized, controlled, noninferiority trial. Singleton pregnant women (n=370) at 320 to 366 weeks of gestation with spontaneous preterm labor or preterm premature rupture of membranes were enrolled. They were randomly assigned (1:1) to a 5-mg or 6-mg dexamethasone group. Dexamethasone was administered intramuscularly every 12 hours for 4 doses or until delivery. The primary outcome was the reduction in neonatal respiratory distress syndrome cases, whereas the secondary outcomes were any adverse maternal or neonatal events. RESULTS: Between December 2020 and April 2022, 370 eligible women, anticipating deliveries within the gestational range of 32 0/7 to 36 6/7 weeks, willingly participated in the study. They were evenly split, with 185 women assigned to the 5-mg group and 185 to the 6-mg group. The study revealed that the demographic profiles of the participants in the 2 groups were remarkably similar, with no statistically significant disparities (P>.05). It is noteworthy that most of these women gave birth after 34 weeks of gestation. Despite a substantial proportion not completing the full course of steroid treatment, the 5-mg dose exhibited noninferiority compared with the 6-mg dose of dexamethasone, as indicated by a modest proportional difference of 0.5% (95% confidence interval, -2.8 to 43.9). Neonatal respiratory distress syndrome occurred in a relatively low percentage of newborns in both groups, affecting 2.2% in the 5-mg group and 1.6% in the 6-mg group. Notably, the risk difference of 0.6% fell comfortably within the predefined noninferiority threshold of 10%. CONCLUSION: Our study suggests that a 5-mg dexamethasone dose is noninferior to a standard 6-mg dose in preventing neonatal respiratory distress syndrome in preterm births.

A Comparative Evaluation of the Effects of N95 and Surgical Facemasks on Pregnant Women Performing Moderate-Intensity Exercise: A Prospective Randomized Study.

Background and objective A facemask is often indicated for the control of the spread of airborne pathogens. At the peak of the COVID-19 pandemic, there was mass enforcement of mask use across the globe. Pregnant women were not excluded. While several studies have been conducted to evaluate and compare the efficacy of various mask types, data on their effects on pregnant women during exercise are scarce. The objective of this study was to evaluate and compare the effects of N95 and surgical facemasks on the cardiopulmonary functions of pregnant women during moderate-intensity exercise. Methods A prospective randomized study was conducted among 104 healthy women with advanced singleton pregnancies performing moderate-intensity exercise wearing either surgical or N95 masks during routine antenatal care. Their respiratory rates were counted, and arterial oxygen saturation (SPO2) and radial pulses (heart rates) were recorded with a mobile digital pulse oximeter at baseline and after 30 minutes of exercise. The mean values were calculated. Data analysis was done using Statistical Product and Service Solutions (SPSS, version 25; IBM SPSS Statistics for Windows, Armonk, NY). An independent t-test was used to compare the mean SPO2 and radial pulse between the two groups. Chi-square was used to examine differences in categorical variables. The level of significance was set at 0.05. Results Their demographic profiles and measured baseline parameters were comparable. Following a 30-minute exercise, the N95 mask group had lower mean SPO2 compared to the surgical mask group (95.5% versus 97.0%; P=0.028, 95%CI; -2.607 to 0.15). Further, the N95 group recorded a higher mean heart rate than the surgical mask group ((97.23 b/m versus 95.02b/m, respectively, mean difference (MD)=2.212, P=0.021, 95%Cl: 1.249-3.672). The mean respiratory rates were also higher among women in the N95 mask group (32.1 c/m versus 29.08 c/m, MD=3.018, 95%CI: 1.392-4.662, P=0.001). Conclusion The study, comparing the relative effects of the surgical and N95 facemask on the cardiorespiratory functions of exercising pregnant women, findings suggest that surgical facemasks may be better tolerated in advanced pregnancy when performing routine antenatal aerobic exercise in comparison with N95 masks.