This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fundamental Concepts, Subject name: Anaesthesia
[{'content': 'Reason of difficult intubation in an obese patient is? \nSelect and explain. \nA. Difficult visualization, B. Decreased safe apnea time, C. Lower tidal volume, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans is \'d\' i.e. All of the aboveReasons for difficult intubation in obese patientsi) Increased soft tissue mass* The increased weight & volume of soft tissue can distort the airway in a supine obese patient, making visualization of vital structures harder.* This can also make "lifting up" on the laryngoscope handle harder, as there is more weight to lift.ii) Increased pressure on diaphragm* Obese abdomens prevent normal diaphragmatic excursion, more so in supine position. This leads to lower tidal volumes in spontaneously breathing patients, faster desaturation once sedated/paralysed, and more difficult bag-valve-mask ventilation.iii) Reduced "Safe Apnoea Time"* This is the time between rendering a patient apnoeic with an anaesthetic, and the time they start to desaturate.* This happens more quickly in obese patients due to the poor mechanics of their airway (mentioned above), and their increased metabolic demands.', 'role': 'assistant'}]