Dogs have 13 ribs that form the supportive structure (rib cage) of the chest cavity. The ribs attach onto the breastbone and the backbones. The vital structures such as the heart and the lungs are protected by the rib cage. The muscles of the chest pull on the ribs during inspiration to increase the size of the chest cavity to pull air into the lungs. As the muscles relax, the rib chest cavity size gets smaller and air is breathed out.
Types of rib tumors
The most common type of rib tumor is osteosarcoma. This is a very malignant tumor and has a rapid spread rate (metastatic). The second most common tumor is chondrosaroma. This tumor has a much lower metastatic potential. Other common tumors that affect the ribs include fibrosarcoma and hemangiosarcoma.
Breeds most commonly to develop rib tumors included Golden Retrievers, mix breeds, Labrador Retrievers, Bassett Hounds, Dobermans, Australian Shepherds, British Bulldog, German Short-haired Pointer, Rough coated Collie, Irish Setter, Giant Pyrenees, Rottweiler, Giant Schnauzer, Shar Pei, and Springer Spaniel. The age of dogs that develop rib tumors tends to be a bimodal distribution with affected dogs being either young (2 to 4.5 years) or older (7 to 9 years).
The most common sign of a rib tumor is a mass that is visibly or palpably present. Lameness of the forelimb may be present if the tumor is located within one of the first four ribs, is compressing the nerves to the limb, is causing mechanical interference with movement of the limb or is invading into the muscles of the forelimb. Labored breathing may be noted if the tumor is very large and is causing collapse of the lung. If the tumor has metastasized to the inside of the chest cavity, fluid may build up in the chest and compress the lungs, thus cause labored breathing.
The diagnosis of a rib tumor is commonly made on x-rays. Typically, the tumor will cause a portion of the rib bone to be dissolved away and/or new bone to be produced within the region of the tumor or both (photo right). Chest x-rays (three views) should be made to rule out visible spread of the tumor to the lungs. A CT scan may be recommended, as this test provides a better evaluation of the extent of the disease and is more sensitive to detect evidence of spread of the tumor into the lungs. A fine needle biopsy may be helpful to diagnose a rib tumor, but frequently will not ascertain the specific type of tumor that is present. Usually the entire tumor is submitted for biopsy after surgery is preformed to establish a final diagnosis. If available, a whole body nuclear bone scan is recommended prior to surgery, as roughly 16%, of the rib osteosarcomas will have spread to other bones at the time of diagnosis. In preparation for surgery, preoperative blood work including a complete blood count, chemistry profile and urine testing are recommended to ensure that your pet is adequately healthy to under go anesthesia and surgery.
The day of surgery
Please make sure that your companion has been fasted prior to surgery and that the prescribed dose of Pepcid AC has been administered. The surgeon will contact you after the surgery to give you a progress report on your companion after the surgery. Our anesthesia and surgical team will prescribe a pain management program, both during and after surgery that will keep your companion comfortable. This will include a combination of general anesthesia, injectable analgesics, local anesthetics, oral analgesics and anti-inflammatory medication.
Surgery is the recommended treatment option for rib tumors. In addition to the rib(s) that are affected by the tumor, one unaffected rib in front and behind the tumor should be removed (photo right). If the tumor is adherent or invading into a lung lobe or the sac surrounding the heart, this tissue will also be removed. In dogs, this is generally tolerated very well. In some cases, a plastic mesh patch will be used to repair the defect in the rib cage. In most cases, a muscle (latissimus dorsi or external abdominal oblique muscle) will be used to repair the defect in the rib cage (photos below left and below right). A drainage tube is placed within the cast cavity and another drainage tube may be placed beneath the skin and muscle flap.
Expected local recurrence is seen in 25% of dogs with incompletely removed tumors and 13.3% of dogs with completely removed tumors. Dogs with osteosarcoma that have elevation of the Alkaline phosphatase enzyme level on chemistry profile have a much lower median survival times (210 days versus 675 days). Chemotherapy will significantly increase the survival of dogs with rib osteosarcoma from a few months to about 9.5 months. Chondrosarcomas have a very good chance to be cured with surgery alone with median survival times exceeding 3 years. Elevation of the alkaline phosphatase enzyme level may also be seen in patients with chondrosarcomas, but does not worsen the prognosis in these cases. These tumors can spread and cause death of the patient. The grade of a chondrosarcoma generally does not correlate with the malignant potential and chemotherapy likely is of little benefit. Hemangiosarcoma generally carries a very poor prognosis regardless of treatment.
Following surgery, the patient will receive pain-relieving medication to ensure a comfortable recovery. A combination of nonsteroidal anti-inflammatory, local anesthetics administered through the chest tube and narcotics administered via a constant intravenous infusion, injection under the skin or via an epidural catheter. Intravenous fluid therapy is administered to ensure that your companion will remain well hydrated after surgery. If needed, oxygen may also be delivered via a small tube that is placed in the nose until your companion is able to breathe well.
At home, the incision should be checked for signs of infection. Your pet should not lick the incision, as this could open the incision or cause infection. If necessary, an Elizabethan collar can be placed on your companion to prevent licking and chewing at the surgical site. The chest will be supported with a bandage for about 2 to 3 weeks after surgery. Antibiotics may be indicated after the surgery in some cases (especially if plastic mesh is used). The respiratory rate may be increased for a few weeks after surgery while the chest wall is healing. In addition, the defect in the chest wall may undulate in and out as the patient breathes, but with time this will resolve or become minimally evident. Exercise should be restricted for about 6 weeks after surgery.
- Liptak JM, Kamstock, DA, Dernell WS, et al. Oncologic outcome after curative-intent treatment in 39 dogs with primary chest wall tumors (1992-2005). Vet Surgery 37:488-496, 2008.
- Liptak, JM, Dernell S, Rizzo SA, et al. Reconstruction of chest wall defects after rib tumor resection: a comparison of autogenous, prosthetic and composite technique in 44 dogs. Vet. Surg 37:479-487, 2008.
- Baines SJ, Lewis S, and White RAS. Vet Record 16:335-339, 2002.
- Matthiesen DT, Clark GN, Orsher RJ, et al. En bloc rib resection of primary rib tumors in 40 dogs. Vet Surg 21:201-20, 1992.
Frequently Asked Questions After Surgery
When should my dog have the first bowel movement after surgery?
- Many dogs will not have a bowel movement for the first 4 to 5 days after surgery
- Reasons that a dog will not have regular bowel movements after surgery include:
- The dog has been fasted prior to surgery
- Dogs do not eat well during the hospital stay
- They frequently do not eat well when they go home
- They are fed highly digestible food that produces little stool
- Pain medication that contain narcotics (such as morphine, fentanyl patches, and tramadol) can be constipating
- If a pet does not have a bowel movement on the 5th day of being home, a stool softener such as metamucil can be fed
- Dose of metamucil is 1 tsp per 25 Kg mixed in with each meal (canned dog food); feed immediately after mixing, as the metamucil will gel the food and may make it less palatable
My pet had surgery and will not eat. What can be done?
- Most pets will not eat their regular dog food after surgery, especially if it is kibble.
- Offer a cooked diet having a 1:1 ratio of a protein source and carbohydrate source. The protein source can be any meat (example: chicken breast, turkey breast, lean hamburger) that is low in fat and should be cooked (drain off all fat after the meat has been cooked). The carbohydrate can be pasta, potato or white rice.
- Try canned dog food; to enhance the flavor sprinkle a very small amount of garlic powder or chicken or beef broth (Chicken-in-a- MugTM or Beef-in-a-MugTM products)
- Try Gerber strained meats for babies such as the chicken, beef, turkey, or veal
- Try Hill's A/D diet available at most veterinary hospitals
- Hand feeding: place a small amount of food in the mouth so that your dog gets the flavor
- Warm the food slightly in a microwave, as the food will be more aromatic; stir the food before feeding and test the temperature on the bottom side of your wrist; it should only be luke warm.
- Remember that most pets will not eat the first day or two after they get home from surgery
- Offer smelly foods that contain fish such as tuna or smelly cat foods
- Try Gerber strained meats for babies such as the chicken, beef, turkey or veal
- Hand feeding: with your finger place a small amount of food on the roof of your cat's mouth; use a syringe to get soft food into the mouth
- Warm the food slightly in a microwave as the food will be more aromatic; remember to stir the food before feeding and test the temperature; it should be only luke-warm
- Some cats will only eat dry food, try kibble if your cat normally has been fed that food
- Petting and stroking your cat frequently will help to stimulate appetite
- Remember that most pets will not eat the first day or two after they get home from surgery
- Appetite stimulants such as cyproheptadine may be helpful
- If your cat refuses to eat anything for 7 days a stomach tube or nasogastric tube should be placed to provide nutrition so that a serious liver problem (hepatic lipidosis) does not develop
My pet is vomiting. What can be done?
- The first thing for you to discern is whether your pet is vomiting or regurgitating. Both will result in fluid or food being brought up. Vomiting always will have heaving or retching of the abdomen prior to expulsion of the vomitus. Regurgitation is not associated with heaving and the pet usually just opens the mouth and fluid or food will be expelled. Usually the regurgited material will be clear or brown colored fluid.
- Next is to identify the cause of the vomiting or regurgitation.
- Causes and treatment of vomiting after surgery
- When some pets return home after a stay in the hospital they may drink excessive amounts of water at one time and then vomit; if this appears to be the case, the water should be limited to frequent smaller amounts.
- Medications such as antibiotics, narcotics or nonsteroidal anti-inflammatory medication commonly cause vomiting after surgery. In order to see which medication is causing the problem, the administration of each drug should be separated 2 hours apart. Usually the pet will vomit or appear nauseated (drooling and sick look) within 1 hour of administration of the medication that they are sensitive to. The antibiotic in some cases may be changed to a different one, or may be discontinued.
- Stomach upset from anesthesia is a potential cause of vomiting and will pass within a couple of days.
- An uncommon cause of vomiting after surgery is internal organ failure. Blood testing will confirm this problem. For this reason vomiting should not be ignored if it persists for more than 24 hours.
- If your pet had surgery of the bowels or stomach, vomiting is always a concern, as it may indicate that infection of the abdominal cavity, called peritonitis, is present. Do not ignore this sign.
- Symptomatic treatment of vomiting involves withholding food for 12 to 24 hours, then introducing small amounts of bland food such as rice and lean cooked hamburger, if your pet does not vomit after that then gradually wean him/her back onto the regular diet after 3 days. In order to decrease the acidity of the stomach, Pepcid AC 0.5 mg/kg can be given by mouth twice daily for 5 days. Metoclopramide and Cerenia are good anti-vomiting medications for dogs and cats. You should always consult a veterinary healthcare professional before administering medication.
- Causes and treatment of regurgitation after surgery
- The most common cause of regurgitation is reflux of acid from the stomach into the esophagus while your pet is under anesthesia. Acidic fluid from the stomach can cause a chemical burn of the esophagus and result in a bad case of heart burn, called esophagitis. This results in poor motility of the esophagus, therefore water and food will accumulate in this structure. In most cases, esphagitis is self-eliminating and will resolve within two or three days.
- If the esophagitis is severe the esophagus may develop one or more strictures. A stricture is a narrowing or stenosis of the esophagus and does not allow passage of food down the esophagus, in regurgitation that lasts longer than one week. This problem should be brought to the attention of your pet's doctor within the first two weeks so that it can be treated by ballooning the stricture (minimally invasive procedure, as it is done with the aide of an endoscope). If an esophageal stricture is chronic surgery is needed.
- Symptomatic treatment of regurgitation caused by esophagitis includes feeding bland food, and administering a coating agent (sucralfate) and an acid blocker (omeprazole or other). Consult a veterinary health care professional if the regurgitation continues for more than a couple of days.
How do I know that my dog is in pain following surgery?
- Signs of pain include
- biting if you get near the surgical site
- grimacing (lips are pulled back and the the dog looks anxious)
- tragic facial expression
- restlessness and unable to sleep; pacing
- if abdominal surgery was done the pet will not lie down on the incision, or will continually sit up in spite of appearing very tired
- the worst pain will be for the first 2 to 3 days after surgery
What can I do to control my dog's pain?
- Narcotic medications that control pain: tramadol, butorphanol, Duragesic (fentanyl patch)
- Anti-inflammatories used to control pain: Deramaxx, Rimadyl, Previcox, or Etogesic
- If an orthopedic surgery has been done cold packing the surgical site may be helpful
- A cold pack may be a pack of frozen peas, crushed ice in a Ziploc bag, or a cold gel pack; place a thin barrier between the skin and the cold pack. An alternative to a cold pack is to freeze water in a styrofoam cup; after frozen cut the bottom of the styrofoam cup out. Cool the surgical site around the incision by rubbing the exposed ice directly on the skin in a circular pattern. Cooling the surgical site helps to numb the area.
How do I know that my cat is in pain following surgery?
- Pain is more difficult to assess in cats versus dogs, as signs can be more subtle and they usually do not vocalize when in pain
- Signs of pain in a cat include the following:
- biting if you get near the surgical site
- growling or deep cry
- not wanting to eat
- hiding and not wanting to be near owner (remember that this could also be caused by the cat just being upset about leaving home and coming back)
What can be done for pain at home for my cat?
- Pain medication such as buprenorphine or a Duragesic (fentanyl) patch
- Tylenol will kill a cat as they lack abundant glutathione enzyme in the liver
- Anti-inflammatories can be used, but the dose is much less than dogs
Is it okay for my pet to lick the incision?
- If a dog licks the incision, the healing process may be delayed.
- Licking can remove stitches and cause the incision to open
- Licking can become a severe habit that is difficult to break
- Licking can cause infection as the mouth has many bacteria
- Dogs will frequently lick the incision when the owner is not watching such as at night time; if the skin looks red or excoriated the most common cause is from licking.
- To stop your pet from licking the following can be tried:
- Elizabethan collar can be placed on the neck; this will not help stop your pet from scratching at the region
- Cervical collar (bite not collar) is a less awkward device and can be effective at stopping a pet from licking the surgical site
- A tee shirt can be used to cover an incision on the chest or front part of the abdomen; gather the waist of the shirt up over the dog's back and wrap an elastic band around this part of the shirt.
- A bandage or sock can be used to cover an incision on a limb; fasten the top of the sock to the dog's limb with tape.
- Bitter apple can be applied around the incision; many dogs will continue to lick after application of this topical
- Bitter Apple and Liquid HeetTM (obtain this from a drugstore...it is used for sore muscles) mixed in a 2:1 ratio can be applied around the skin incision
- Antipsychotic medication in some cases is needed