Publications by authors named "Praud J"

Gastroesophageal refluxes (GERs) are universal in newborns and may induce deleterious consequences, especially in preemies. We have previously shown that nasal continuous positive airway pressure (nCPAP) inhibits GERs in full-term lambs, complementing similar results in adult humans. The effect of high-flow nasal cannula (HFNC) on GERs, however, remains unknown.

View Article and Find Full Text PDF

Home noninvasive ventilation (NIV) for children must consider the key role of the interface, in addition to selecting the ventilatory mode and settings. Acceptance and adherence to NIV often depend on the time spent selecting the right mask, as well as on regular and careful attention to preventing and addressing various issues that arise during NIV.

View Article and Find Full Text PDF

Objective: To determine if change in body position improves oxygen requirements and respiratory mechanics during the transition from total liquid ventilation (TLV) to gas ventilation.

Methods: Fourteen piglets underwent TLV, followed by a 2-hour weaning period under conventional gas ventilation. Subjects were randomized to the experimental group (Rotating - R), that was in prone position between the 10th and 30th minute of weaning, or to the static control group (Supine - S).

View Article and Find Full Text PDF

Background: Periodic breathing (PB)-related intermittent hypoxia can have long-lasting deleterious consequences in preterm infants. Olfactory stimulation using vanilla odor is beneficial for apnea of prematurity in the first postnatal days/weeks. We aimed to determine for the first time whether vanilla odor can also decrease PB-related intermittent hypoxia.

View Article and Find Full Text PDF

Background: The evolution and treatment of lung alterations related to congenital spine and chest wall deformities (CWD) are poorly understood. Most animal models of CWD created postnatally were not evaluated for respiratory function. The goal of our study was to evaluate the effects of a CWD induced in utero on lung growth and function in an ovine model.

View Article and Find Full Text PDF

Background: Significant cardiorespiratory events can be triggered in preterm infants as part of laryngeal chemoreflexes (LCRs) and esophageal reflexes (ERs). We previously showed that nasal continuous positive airway pressure (nCPAP) blunted the cardiorespiratory inhibition induced with LCRs. Therefore, we aimed to compare the effects of nCPAP and high-flow nasal cannulas (HFNC) on the cardiorespiratory events induced during LCRs and ERs.

View Article and Find Full Text PDF

Background: This study aimed at comparing cardiorespiratory stability during total liquid ventilation (TLV)-prior to lung aeration-with conventional mechanical ventilation (CMV) in extremely preterm lambs during the first 6 h of life.

Methods: 23 lambs (11 females) were born by c-section at 118-120 days of gestational age (term = 147 days) to receive 6 h of TLV or CMV from birth. Lung samples were collected for RNA and histology analyses.

View Article and Find Full Text PDF

Background: Apelins are potential candidate therapeutic molecules for hemodynamic support. The objective of this study was to assess the hemodynamic impacts of apelin-13 in a neonatal lamb model of septic shock.

Methods: Lambs were randomized to receive apelin-13 or normal saline.

View Article and Find Full Text PDF

Objectives: To describe the current clinical practice patterns of Canadian pediatric respirologists at pediatric tertiary care institutions regarding chronic tracheostomy tube care and management of home invasive ventilation.

Methods: A pediatric respirologist/pediatrician with expertise in tracheostomy tube care and home ventilation was identified at each Canadian pediatric tertiary care center to complete a 59-item survey of multiple choice and short answer questions. Domains assessed included tracheostomy tube care, caregiver competency and home monitoring, speaking valves, medical management of tracheostomy complications, decannulation, and long-term follow-up.

View Article and Find Full Text PDF

Objective: To compare conventional gas ventilation (GV) and high-frequency oscillatory ventilation (HFOV) for weaning from total liquid ventilation (TLV).

Methods: Sixteen lambs were anesthetized. After 1 h of TLV with perflubron (PFOB), they were assigned to either GV or HFOV for 2 h.

View Article and Find Full Text PDF

Background: Respiratory viruses can be responsible for severe apneas and bradycardias in newborn infants. The link between systemic inflammation with viral sepsis and cardiorespiratory alterations remains poorly understood. We aimed to characterize these alterations by setting up a full-term newborn lamb model of systemic inflammation using polyinosinic:polycytidylic acid (Poly I:C).

View Article and Find Full Text PDF

Convalescing preterm infants often require non-invasive respiratory support, such as nasal continuous positive airway pressure or high-flow nasal cannulas. One challenging milestone for preterm infants is achieving full oral feeding. Some teams fear nasal respiratory support might disrupt sucking-swallowing-breathing coordination and induce severe cardiorespiratory events.

View Article and Find Full Text PDF

Sepsis is a prevalent life-threatening condition related to a systemic infection, and with unresolved issues including refractory septic shock and organ failures. Endogenously released catecholamines are often inefficient to maintain blood pressure, and low reactivity to exogenous catecholamines with risk of sympathetic overstimulation is well documented in septic shock. In this context, apelinergics are efficient and safe inotrope and vasoregulator in rodents.

View Article and Find Full Text PDF

Background: There is no universally accepted method to assess the pressure-generating capacity of inspiratory muscles in children on mechanical ventilation (MV), and no study describing its evolution over time in this population.

Methods: In this prospective observational study, we have assessed the function of the inspiratory muscles in children on various modes of MV. During brief airway occlusion maneuvers, we simultaneously recorded airway pressure depression at the endotracheal tube (ΔPaw, force generation) and electrical activity of the diaphragm (EAdi, central respiratory drive) over five consecutive inspiratory efforts.

View Article and Find Full Text PDF

While phasic electrical activity of the cricopharyngeus muscle (EAcp)-the main component of the upper esophageal sphincter-occurs with inspiration and forceful expiration in adults, no such data is available for newborns. In addition, the effect of nasal respiratory support commonly used in newborns is unknown. We aimed to describe the phasic respiratory EAcp and to assess the potential effect of nasal CPAP (nCPAP, 6 cmHO) or high-flow nasal cannula (HFNC, 7 L/min) in newborn lambs during 6-h recordings.

View Article and Find Full Text PDF

Newborn infants with respiratory difficulties frequently require nasal respiratory support such as nasal continuous positive airway pressure (nCPAP) or high-flow nasal cannulae (HFNC). Oral feeding of these infants under nasal respiratory support remains controversial out of fear of aspiration and cardiorespiratory events. The main objective of this study was to evaluate the safety of oral feeding under different types of nasal respiratory support in newborn lambs without or with tachypnea.

View Article and Find Full Text PDF

This review focuses on the delivery of non-invasive ventilation-i.e., intermittent positive-pressure ventilation-in children lasting more than 3 months.

View Article and Find Full Text PDF
Article Synopsis
  • Total liquid ventilation (TLV) may reduce ventilator-induced lung injury (VILI) in newborns compared to conventional gas ventilation, but optimal TLV parameters remain unclear.
  • In a study with newborn lambs, two groups were tested with low (L-V) and high (H-V) liquid tidal volumes to compare lung inflammation and weaning impacts.
  • Results showed no significant differences in inflammation scores between L-V and H-V, but L-V lambs exhibited higher mRNA expression levels, suggesting distinct inflammatory responses that require further investigation.
View Article and Find Full Text PDF

Although it is well known that neonatal sepsis can induce important alterations in cardiorespiratory control, their detailed early features and the mechanisms involved remain poorly understood. As a first step in resolving this issue, the main goal of this study was to characterize these alterations more extensively by setting up a full-term newborn lamb model of systemic inflammation using lipopolysaccharide (LPS) injection. Two 6-h polysomnographic recordings were performed on two consecutive days on eight full-term lambs: the first after an IV saline injection (control condition, CTRL); the second, after an IV injection of 2.

View Article and Find Full Text PDF

Background: Although it is commonly accepted that upper airway obstruction (UAO) increases gastroesophageal reflux (GER), the link is poorly understood and insufficiently documented. In addition, while hypoxia is often encountered in infants with UAO, its consequences on GER are virtually unknown. The two aims of the present study were to characterize the effects of (1) UAO and (2) hypoxia on GER.

View Article and Find Full Text PDF

Introduction: Obstructive sleep apnoea affects up to 6% of children worldwide. Although current guidelines recommend systematic tonsillectomy and adenoidectomy, many children do not benefit from these interventions. Drug-induced sleep endoscopy (DISE) allows the dynamic evaluation of patients' airways to identify the specific anatomic sites of obstruction.

View Article and Find Full Text PDF

The present study aimed to further unravel the effects of nasal continuous positive airway pressure (nCPAP) on the cardiovascular and respiratory systems in the neonatal period. Six-hour polysomnographic recordings were first performed in seven healthy newborn lambs, aged 2-3 days, without and with nCPAP application at 6 cmHO (nCPAP-6), in randomized order. The effects of nCPAP-6 on heart rate variability, respiratory rate variability, and cardiorespiratory interrelations were analyzed using a semiautomatic signal processing approach applied to ECG and respiration recordings.

View Article and Find Full Text PDF