Clinical trial NCT03239678: Safe Time for Apnea After Preoxygenation
Official title: Safe Time for Apnea After Preoxygenation With Different Oxygen Concentration During the Induction of General Anesthesia
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Anesthesia, General
Keywords: Preoxygenation
Oxygen Concentration
Lead sponsor: Sixth Affiliated Hospital, Sun Yat-sen University
Sponsor class: OTHER
First posted: 2017-08-04
Enrollment: 90
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: The use of 100% oxygen during the induction of general anesthesia is always preferable to have enough time to secure the airway by endotracheal intubation, because preoxygenation with a low oxygen concentration may reduce the safe time for apnea. However, using a low oxygen concentration during preoxygenation might prevent the formation of atelectasis. There is still no clear conclusion about the best oxygen concentration for preoxygenation. Our study is designed to evaluate the safety of preoxygenation with 80%, 60%, 40%, 30% and 21% oxygen by the safe time for apnea during the induction of general anesthesia.

Detailed description: We decide to add 3 groups (80%, 60%, and 40% oxygen) in our study to fully evaluate the safety of preoxygenation with different oxygen concentration.

Zijia Li 2018.3.2

Eligibility criteria: Inclusion Criteria:

* Nonsmoking patients aged 18 years to 60 years
* Undergoing general anesthesia for elective surgery
* Pulse oxygen saturation ≥95% when breathing air quietly in bed
* American Society of Anesthesiologists(ASA) physical status class I-II
* Informed consent can be obtained

Exclusion Criteria:

* A suspected difficult airway
* Be allergic to midazolam, propofol , fentanyl or Cisatracurium
* Severe disease of respiratory system or cardiovascular system,or obstruction of the digestive tract
* Oxygen reserve is suspected low,or patient who does not tolerate hypoxemia well
* A history of mental disorder or patient who can not collaborate well
* Body mass index more than 30 kg/㎡

Primary outcomes:
measure: Safe time for apnea
timeFrame: 10 min
Secondary outcomes:
measure: Time needed for endotracheal intubation
timeFrame: 1 min
Other outcomes:
Locations:
city: Guangzhou
country: China
facility: Department of Anesthesia ,the Sixth Affiliated Hospital of Sun Yat-sen University
state: Guangdong
Study officials:
affiliation: Sixth Affiliated Hospital, Sun Yat-sen University
name: Sanqing Jin, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: Sixth Affiliated Hospital, Sun Yat-sen University
name: Zijia Li
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lundquist H, Hedenstierna G, Strandberg A, Tokics L, Brismar B. CT-assessment of dependent lung densities in man during general anaesthesia. Acta Radiol. 1995 Nov;36(6):626-32.
citation: Rothen HU, Sporre B, Engberg G, Wegenius G, Reber A, Hedenstierna G. Prevention of atelectasis during general anaesthesia. Lancet. 1995 Jun 3;345(8962):1387-91. doi: 10.1016/s0140-6736(95)92595-3.
citation: Edmark L, Kostova-Aherdan K, Enlund M, Hedenstierna G. Optimal oxygen concentration during induction of general anesthesia. Anesthesiology. 2003 Jan;98(1):28-33. doi: 10.1097/00000542-200301000-00008.