Effects of Different Oxygen Concentrations on Lung Ultrasound Score During Spontaneous Ventilation
Condition: Pulmonary Atelectasis
MeSH terms: Pulmonary Atelectasis
Study type: Interventional

Summary: 
      The goal of this study is to observe the effects of different oxygen concentrations during
      preoxygenation in spontaneous breathing patients with modified lung ultrasound scores before
      induction of general anesthesia. Preoxygenation is a routine and recommended procedure for
      patients undergoing general anesthesia. Atelectasis is a common side effect of general
      anesthesia and usage of high concentration oxygen is a probable cause of it. Using lower
      oxygen concentrations in preoxygenation may help reducing the atelectasis and it can be
      assessed by lung ultrasound.
    

Detailed description: 
      Preoxygenation is the process of supplying the patient a high inspired fraction of oxygen
      prior to an airway intervention or induction of general anesthesia. Prolonging safe apnea
      duration is the primary aim of preoxygenation and preoxygenation is recommended for all
      patients before induction of general anesthesia.

      Atelectasis is the most common postoperative pulmonary complication and is associated with
      usage of high inspired fraction of oxygen. Modified lung ultrasound scoring is an effective
      and noninvasive method to determine atelectasis. In this study we will observe the effects of
      different oxygen concentrations during preoxygenation before induction of general anesthesia
      in spontaneous breathing patients with modified lung ultrasound scores .

      Patients undergoing general anesthesia for elective surgery meeting the criteria will be
      acknowledged about the study. After written consents are taken patients will be randomised
      into two groups by coin method. One group will receive %80 oxygen for 3 minutes and other
      group will receive %100 oxygen for 3 minutes during preoxygenation. Each participants
      demographic data will be collected. 12 quadrants of thorax divided by midsternal line,
      anterior axillary and posterior axillary lines will be examined by the usage of modified lung
      ultrasound score before and at the end of preoxygenation for all individuals. Randomisation,
      lung ultrasound scoring and preoxygenation will be done by different experienced
      anesthesiologists so the observers of this study would be blinded for the results. Patients
      will be blinded for the concentration of oxygen. Modified lung scores of each group would be
      compared at the end of the study.
    

Intervention name(s): %80 Oxygen concentration; %100 Oxygen concentration
Intervention type(s): Other; Other
Intervention description(s): Patients will be administered %80 Oxygen for 3 minutes during preoxygenation.; Patients will be administered %100 Oxygen for 3 minutes during preoxygenation.
Other intervention name(s): %80 Inspired fraction of oxygen; %100 Inspired fraction of oxygen
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Screening
Keywords: atelectasis; preoxygenation; lung ultrasound; general anesthesia