Clinical Trial: High-Flow Heated and Humidified Oxygen Therapy and Gastric Distension
Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Interventional
Official Title: Prospective Study on the Possible Effects of High-Flow Heated and Humidified Nasal Oxygen Therapy (HFNO) on Gastric Distension
Brief Summary: High Flow Heated and Humidified Nasal Oxygen therapy (HFNO) has been increasingly used in emergency medicine to assist patients with short term respiratory failure and to provide adequate oxygen to the body prior to intubation. Gastric distension which is the bloating of the stomach due to air being pumped into it is a concern for anesthesiologists as it increases the risk of nausea and vomiting during surgery (aspiration). The objective of this study is use an ultrasound machine to measure the volume of fluid in the stomach before and after HFNO is used in a standard clinical manner.
Detailed Summary:
High Flow Heated and Humidified Nasal Oxygen therapy (HFNO) is being increasingly used in the emergency medicine and intensive care settings to manage patients with acute hypoxemic respiratory failure, and to optimize pre-oxygenation prior to intubation in patients with mild-to-moderate hypoxemia. More recently, there have been reports of applications in the anesthesia perioperative setting. In fact, it is possible that the single greatest potential advantages of HFNO for anesthesia practice is that (unlike face mask and CPAP devices) oxygen administration can be maintained during periods of apnea with the potential to significantly prolong the apnea time available for safe and effective airway management. However, the low levels of positive airway pressure associated with HFNO has raised the question of whether prolonged use could result in gastric insufflation thus increasing the risk of regurgitation and aspiration with an unprotected airway. Gastric distension is a concern for anesthesiologists because it leads to the activation of a parasympathetically-mediated reflex through the vagus nerve that leads to secretion of acetylcholine by enteric neurons. In turn, increased acetylcholine activates M3 receptors on parietal cells resulting in increased secretion of gastric acid. The combination of an increased volume of gastric secretions and high intraluminal pressure may place patients at risk of pulmonary aspiration.
The primary objective will be any change in gastric fluid volume from the baseline to each scan following HFNO therapy. Participants will undergo an abdominal ultrasound scan prior to any oxygen therapy to provide a baseline. Two 15-minute sessions of oxygen therapy will follow. After each 15-minute session, another ultrasound scan will take place, identical to the baseline to obtain the same measurements. From the images taken by the ultrasound, a mathemat
Sponsor: University Health Network, Toronto
Current Primary Outcome: Change in Gastric Volume [ Time Frame: Prior to, and immediately following each session of HFNO oxygen therapy. ]
Original Primary Outcome: Same as current
Current Secondary Outcome: Gastric Distension [ Time Frame: Immediately following each session of HFNO oxygen therapy. ]
Original Secondary Outcome: Same as current
Information By: University Health Network, Toronto
Dates:
Date Received: February 16, 2017
Date Started: May 2017
Date Completion: February 2018
Last Updated: April 25, 2017
Last Verified: February 2017
