Anaesthesia All of the following are used to maintain proper oxygen flow to the patient except – A Placement of Oxygen flowmeter downstream of the Nitrogen flowmeter B A proportionater between N2 and O2 control valve C Different pin index for nitrogen and oxygen D Calibrated oxygen concentration analyses 💡 Explanation All of the following are used to maintain proper oxygen flow to the patient except – ✓ Correct Answer: C. Different pin index for nitrogen and oxygen