Hypoxemia | The Performance of Two Oxygen Delivery Devices Used After General Anesthesia.

Hypoxemia research study

What is the primary objective of this study?

After general anesthesia, there are the risks for airway obstruction, hypoventilation, atelectasis, ventilation-perfusion mismatch, hypercarbia and hypoxemia,so oxygen supplement in PACU seems necessary. This study aim is to compare the two methods of oxygen supplement which are 1.nasal cannula at O2 flow 4 L/min. 2.oxygen mask with O2 flow 5 L/min. The hypothesis in this study is the 2 methods can equally provide effective oxygen supplement to prevent anesthesia-related hypoxemia. Choosing nasal cannula would be reasonable because it is cheaper and more comfortable to patient.

Who is eligible to participate?

Inclusion Criteria: - General anesthesia - Age 18-70 years - American Society of Anesthesiology (ASA)physical status 1-3 - Elective case Exclusion Criteria: - ASA physical status class 4 or more - Unstable pulmonary diseases - BMI > 35 kg/m2 - oxygen saturation < 94% when breathing in room air - Respiratory muscle weakness eg.myasthenia gravis - Central nervous system abnormalities eg.drowsiness, hypoventilation - Patients who have been intubated or needed ventilatory support before operation - Plan to remain intubated after the operation - Intracranial, intrathoracic and upper abdomen surgery - Patients who nasogastric tube is inserted - Airway problems eg. sinusitis - Nasal cavity related surgery or nasal packing eg. endoscopic sinus surgery - Patient refusal

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?


Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Device:oxygen mask

Device:oxygen cannula

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

oxygen maskOxygen mask with oxygen flow 5 L/min will be given to allocated post general anesthesia patients. The incidence and causes of hypoxemia will be recorded.

Oxygen cannulaOxygen cannula with oxygen flow 4 L/min will be given to allocated post general anesthesia patients. The incidence and causes of hypoxemia will be recorded.

Study Status


Start Date: April 2013

Completed Date: December 2014

Phase: N/A

Type: Interventional


Primary Outcome: Number of Participants With Hypoxemia in Both Groups

Secondary Outcome: The Causes of Hypoxemia

Study sponsors, principal investigator, and references

Principal Investigator: Manee Raksakietisak, MD

Lead Sponsor: Mahidol University


More information:

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