Frenchies are a Brachycephalic breed - a visualize word which essentially means dogs (and cats, in the case of Persians and some other breeds) with short muzzles, flat faces and strong breathing methods.
This is what's accountable for the sweet snorting and snuffling sounds your Frenchie makes - but it's also a severe matter for your dog's health. They also merge to make anesthetic a serious matter for the breed. Anesthetic should only ever be administered for the most dangerous of procedures - no 'putting under' for simple nail clippings, please. Isoflourine is the most accepted type of anesthesia, for various reasons, but this is a topic best argued with your Veterinarian.