Prevention of atelectasis in morbid obese patients during induction of general anesthesia

Confirmation of atelectasis is possible through a variety of means:(1) Imaging studies: conventional chest radiology, CT, MRI, ultrasonography and intravital microscopy.(2) Laboratory studies: For assessment of patient oxygenation.Prevention of atelectasis formation is an important goal. Several interventions were studied with proven efficacy and the use of one, or combining more than one, of the described methods can help prevent atelectasis or even reopen collapsed tissue.Lung inflation to an airway pressure of 40 cmH2O for 15 seconds can fully re-expand atelectatic lung tissue that develops after induction of general anesthesia.Alveolar recruitment strategy using PEEP increased to 15 cmH2O and tidal volume to either 18 ml/kg or to a volume that caused a peak airway pressure of 40 cmH2O for 10 breaths. This strategy should be performed after 30 minutes from the start of surgery where the lungs mechanically ventilated using oxygen concentration of 40%.Atelectatic formation can be prevented during induction of general anaesthesia by using low FiO2 and use of PEEP. THe use of PEEP with 100% oxygen during induction of general anesthesia prevents the development of atelectasis while avoiding the high risk associated with using low FiO2 which is important in obese patients.Use of 80% oxygen is considered before tracheal extubation to prevent atelectasis in early postoperative period.