I got the Comfy Cone and adore it. Adore it. No bruises or knocked over tables or dogs stuck in doorways! Although in this house we are fans of Calvin Klein boxer briefs, for the discerning newf. We hadn't ordered the Comfy Cone in advance and no one, NO ONE, had the plastic cones large enough. The boxer briefs worked for a few days until Nanook figured out how to wriggle his nose up the leg hole. :roflmao: Incidentally, if you're ever feeling bored, call all of your local pet stores looking for bitch heat diapers for a 140 lb dog. Say things like, "no I don't think you understand. He's got a really, really big butt. I'm talking huge."
Advice for the surgery - find out if your vet intends to keep him overnight, and if so, if there is a vet tech and vet on duty 24 hours a day. You don't want your baby there without someone watching him because these big dogs can sometimes have complications after anesthesia. If there isn't someone there 24 hours, insist on bringing him home so that you can watch him yourself.
Make CERTAIN that the vet uses heating pads during and after surgery, bair huggers etc. Drops in temperature in these big guys can be dangerous. The recovery room should be heated and Charlie should have blankets to keep his temperature stable.
Ask your vet when you can administer food and water post-surgery, and for how long he wants you to keep Charlie quiet. Usually they say short leashed walks only for one week, no running, no jumping, no rough housing.
For the first few hours after he comes out from anesthesia, if he's with you, check that he is responsive to words and physical stimuli every so often. He'll be nappish and that's okay - you just want to make sure that it's normal sleep.
You'll want to verify that he urinates within 24 hours of the surgery - it's normal for them to skip bowel movements but they should be able to pee.
Your vet will probably recommend that you monitor the sutures for excess bleeding, or signs of infection - redness that increases instead of decreasing, heat, pus. He might send Charlie home with antibiotics just in case. Some bleeding into the scrotal sac is normal - the blood is usually reabsorbed into the body. If you're especially nervous, you can buy a digital thermometer and monitor his temperature for the first few days after surgery.
Stock bags of frozen veggies to apply to his wounded manhood - Nanook used to clamp his legs down around it to keep it in place when I put it on for him! That area will be sore for a while; ice feels good and helps to cut down on bleeding under the skin/the reabsorption of blood. I did ten minutes on, ten minutes off.
Finally - you may notice lumps under the skin attached to either side of his penis shaft. These are not testicles. They are glands. Do not make the mistake of bringing the dog into the veterinarian, and accusing them of failing to remove the testicles, and pointing to the lumps. :roflmao: Not that I know anyone that did that. *cough, cough*