Cardiopulmonary haemodynamic effects and gas exchange during apnoeic oxygenation with high-flow and low-flow nasal oxygen: A large animal study.

Background: Apnoeic oxygenation with high-flow nasal oxygen prolongs the safe apnoeic period during induction of general anaesthesia. However, central haemodynamic effects and the characteristics of central gaseous exchange remain unexplored.

Objective: To describe mean pulmonary arterial pressure along with arterial and mixed venous blood gases and central haemodynamic parameters during apnoeic oxygenation with low-flow and high-flow nasal oxygen in pigs.

Pre-oxygenation using high-flow nasal oxygen in parturients undergoing caesarean section in general anaesthesia: A prospective, multi-centre, pilot study.

Background: Parturients undergoing caesarean section in general anaesthesia have an increased risk of desaturating during anaesthesia induction. Pre- and peri-oxygenation with high-flow nasal oxygen prolong the safe apnoea time but data on parturients undergoing caesarean section under general anaesthesia are limited. This pilot study aimed to investigate the clinical effects and frequency of desaturation in parturients undergoing caesarean section in general anaesthesia pre- and peri-oxygenated with high-flow nasal oxygen and compare this to traditional pre-oxygenation using a facemask.

Biomarkers for oxidative stress and organ injury during Transnasal Humidified Rapid-Insufflation Ventilatory Exchange compared to mechanical ventilation in adults undergoing microlaryngoscopy: A randomised controlled study.

Background: Apnoeic oxygenation using Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) during general anaesthesia prolongs the safe apnoeic period. However, there is a gap of knowledge how THRIVE-induced hyperoxia and hypercapnia impact vital organs. The primary aim of this randomised controlled trial was to characterise oxidative stress and, secondary, vital organ function biomarkers during THRIVE compared to mechanical ventilation (MV).

Lung volume changes in Apnoeic Oxygenation using Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) compared to mechanical ventilation in adults undergoing laryngeal surgery.

Background: Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) using high-flow 100% oxygen during apnoea has gained increased use during difficult airway management and laryngeal surgery due to a slower carbon dioxide rise compared to traditional apnoeic oxygenation. We have previously demonstrated high arterial oxygen partial pressures and an increasing arterial-alveolar carbon dioxide difference during THRIVE. Primary aim of this study was to characterise lung volume changes measured with electrical impedance tomography during THRIVE compared to mechanical ventilation.

Upper Airway Collapsibility during Dexmedetomidine and Propofol Sedation in Healthy Volunteers: A Nonblinded Randomized Crossover Study.

Background: Dexmedetomidine is a sedative promoted as having minimal impact on ventilatory drive or upper airway muscle activity. However, a trial recently demonstrated impaired ventilatory drive and induction of apneas in sedated volunteers. The present study measured upper airway collapsibility during dexmedetomidine sedation and related it to propofol.

Sedation with Dexmedetomidine or Propofol Impairs Hypoxic Control of Breathing in Healthy Male Volunteers: A Nonblinded, Randomized Crossover Study.

Background: In contrast to general anesthetics such as propofol, dexmedetomidine when used for sedation has been put forward as a drug with minimal effects on respiration. To obtain a more comprehensive understanding of the regulation of breathing during sedation with dexmedetomidine, the authors compared ventilatory responses to hypoxia and hypercapnia during sedation with dexmedetomidine and propofol.

Methods: Eleven healthy male volunteers entered this randomized crossover study.