I'd definitely flush her vent with cool (not warm) water - use a baby's ear syringe or turkey baster. This will help cool her tissues as well as flush out bits of shell.
Then since she had this happen, and might have cuts, I'd just go ahead and put her on penicillin injections for four days to prevent this sort of infection and treat in case something already started brewing inside.
I'll post information on Penicillin G procaine which is easily found at most feed stores in the refrigerator section. That article will be a the bottom here. If a different penicillin (and pen is the only applicable antibiotic that you can get without a prescription - the foil packet ones don't apply.
Laying crumbles are fine - as long as it's layer; also make sure they have free choice oyster shell.
Incidentally I have to say cheers to you and your husband for actually palpating her for the egg pieces.
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USING PENICILLIN G PROCAINE FOR POULTRY by Nathalie Ross
Sometimes when faced with injured chickens or waterfowls we feel it is necessary to treat with antibiotics to either stop an infection, or prevent one from happening.
People often turn to their local feed store for packaged antibiotics, believing that they are appropriate for nearly all occasions. Unfortunately, these antibiotics in the water actually aren't the ones that work for infected 'wounds'. They are intended for respiratory illnesses and enteritis. The antibiotics that are appropriate for wounds are of the penicillin range, or penicillin related medicines. (Penicillin, Penicillin G Procaine, amoxicillin, etc). With the exception of amoxicillin, these drugs are most often (and most effectively) given by injection. This is particularly true of the penicillin drugs as they are very rough on the beneficial flora of the birds digestive tract if given orally.
Penicillin injection medicines are readily available at most feed stores; they are kept and stored in the refrigerator and should be at home as well. One of my preferred drugs for wound use, and commonly found in most stores, is Penicillin G Procaine (300,000 IU).
Penicillin is a mixture of drug particles (solids) in liquid (solution). The particles in the solution are quite large, the drug is quite thick (particularly when stored correctly in the refrigerator) so you need a larger needle to get the correct mixture of particles in solution for an injection.
Most feed stores carry 3 cc syringes pre-equipped with screw-on needles that are 25 gauge (smaller). Of course, to keep the syringe sterile, leave the needle on. The same feedstores often carry loose 18 gauge sterile needles. Buy one for each syringe. Just before you plan to pull the penicillin from the vial for the shot, remove the syringe from its packaging and unscrew the smaller needle, screw on the larger needle with its cap still on. Make sure it is screwed tightly.
Pulling the medicine: penicillin particles settle during storage. Shake the penicillin vial until the solids on the bottom are all mixed into the liquid. Uncap the syringe, and pull the plunger out 1/4cc. Push the needle into the rubber top of the vial and press the plunger to let the air into the vial. Then pull your dosage. Pull out the syringe, turn the needle up, and thump with your finger to dislodge any air bubbles from the syringe to the top of the syringe. Push the plunger gently to push out the air. Re-cap the needle; letting that syringe just come to nearly room temperature. Replace the vial into the refrigerator as soon as the injection is pulled.
Penicillin is given in the muscle (IM aka intramuscularly). On poultry/waterfowl, the best place to give the shot is either in the breast meat or in the thigh. I prefer in the breast meat as there is a great deal of meat, little bone, and few blood vessels.
Clean a spot far from the bone, in the middle of one half of the breast, with a tiny bit of alcohol on a bit of tissue. Uncap the syringe and put the needle into the skin not terribly far. Less than ¼ inch for sure. Pull its plunger first and look for blood. This is to make sure the needle is not in a blood vessel. If you see blood, withdraw the needle and move the injection sight. Repeat. If you don't see blood, push the plunger in and then remove the syringe from the bird.
Pen G procaine is given daily for no more than four days. The dosage for poultry or waterfowl (under 10 pounds) is listed as less than 1/4 cc if the Penicillin G Procaine is 300,000 I.U. (which is most often is) for animals from 1-10 kg (each kg = 2 pounds, so 1-20 pounds). The dosage is actually listed as 1ml (cc) per 100 pounds of body weight, but giving 1/10th of a cc would be troublesome and it has a high safety margin.
