Gastric Distention Clinical Trial
Official title:
Does High-Flow Heated and Humidified Nasal Oxygen Therapy (HFHHNO) Result in Gastric Distension? A Two-center Prospective Study
High Flow Heated and Humidified Nasal Oxygen therapy (HFHHNO) 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.
High Flow Heated and Humidified Nasal Oxygen therapy (HFHHNO) 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 HFHHNO 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 HFHHNO 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 HFHHNO therapy. Participants will undergo an abdominal ultrasound scan prior
to any oxygen therapy to provide a baseline. One 30-minute session of oxygen therapy will
follow(up to 60-70 L/min). After session, another ultrasound scan will take place, identical
to the baseline to obtain the same measurements. From the images taken by the ultrasound, a
mathematical model can be applied to calculate the gastric volume (and any change).
The secondary outcome will be the incidence of "gastric air distension" defined by
qualitative ultrasound as a distended antrum with air content that blurs the posterior
gastric wall.
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| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Completed |
NCT04629911 -
High Flow Nasal Oxygenation and Gastric Insufflation in Anesthetized Patients
|
N/A |