A child who is a known case of bronchial asthma comes with respiratory rate 48/min, cannot speak 2 words, occasional wheeze and oxygen saturation of 95%. You give 3 doses of salbutamol nebulisation then he staed to speak a sentence but saturation falls to 85%. What is the cause?
Bronchomalacia Right to left shunt VP mismatch with dead space ventilation Faulty pulse oxy-meter