Cervical fracture or the C2 vertebra Tiffany Mullany 1362600
Abstract:
An 18 month old female Labrador was referred to the veterinary specialist group on the 08/08/11 for evaluation of a cervical spinal fracture of the C2 vertebra. The dog sustained injury after running into a car. Radiographs had shown evidence of an articular fracture to the C2 vertebra, with no other signs of neurologic injury, except cervical pain. Bloods showed an elevation of ALP and AST which can be consistent with muscle trauma. (American association for clinical chemistry 2001-2011). Surgery was performed to stabilize the C2 vertebra, which will allow full rotation when the patient recovers. The patients anesthetic was uneventful and she made a full recovery.
Signalment:
Name: Bell
Breed: Chocolate Labrador
Age: 18 months
Sex: Female, spayed
Weight: 16.3kg
Date of procedure: 09/08/11
Introduction:
On the 08/08/11, Bell was presented to Dr Richard Jerram after being referred from a clinic in Gisbourne. Bell had run into a car a week prior to admission to VSG. Radiographs were taken, which showed evidence of cervical spinal fracture of the C2 vertebra. C.T scan and abdominal ultrasound were also performed at VSG. The C.T scan confirmed that surgery was needed. The abdominal ultrasound showed no other significant abnormalities. The tests and images were shown to the owners and surgical treatment was authorized.
Patient History:
The patient had been in good health before the recent accident. Although the owners had made a mention that she had not grown as well as her litter mates and was a lot smaller. No other significant history was noted on the patient’s records. As she was a referral case, previous records of vaccinations and check-ups were not noted.
Hospital care:
The patient was placed in cage in the treatment area for observation. She was only to be walked and taken to the toilet on a harness. No leads were to be around her near her neck, due to the nature of the injury. The patient was then made comfortable and left to adjust to the new settings. All bowls had to also be elevated for her comfort.
Examination:
Mucous membrane colour and capillary refill time were recorded as normal. Thoracic auscultation (Callan, Robert J 2011) and abdominal palpation were also recorded as normal. The dog was ambulatory with no evidence of ataxia or paresis (Shaw, Darcy H 2011). Placing responses were normal in all four limbs. Myotactic reflexes were normal (Matthews, Gary G 2000). Pain was elicited on gentle palpation of the cranial cervical spine, particularly on the left side. Cranial nerves normal. No other significant orthopedic or neurological abnormalities were detected.
Diagnosis:
Thoracic radiography, abdominal ultrasonography, and computed tomography (CT) of the cervical spine were taken to confirm the fracture to the C2 vertebra and to have images during surgery as a reference. Routine bloods were taken and showed an elevated ALP and AST (American association for clinical chemistry 2001-2011), which is consistent with muscle trauma. The dog was booked in for surgical stabilization of the C2 fracture.
Catheterization:
A small area over the left cephalic vein was clipped with a #40 surgical blade. The skin was prepared with two cotton balls with microsheild 4/ chlorhexadine soap to wash any dirt and clean the skin. Then a final prep with a cotton ball with alcohol. A 23ga intravenous catheter was used and placed into the right cephalic vein. This was taped using hyperfix 1” tape. An IV port was also placed to allow easy access to the catheter. Then 2mls of heparin saline was used to flush the catheter and make sure the catheter flowed without any blood clots. Soft ban and vet wrap were used as a final bandage to secure the catheter but also to leaving the t-port out of the bandage for access.
Fluid plan:
Fluids are used to maintain patient hydration and to compensate for any fluid loss via bleeding or diarrhoea. For Bells surgery two calculations were made, there was a maintenance rate and a surgical rate:
Maintenance: 60 x 16.3 (weight in kgs) = 978 mls/day
978mls/day / 24 hours = 40.75ml/hour
Surgical: 10 x 16.3 (weight in kgs)= 163ml/day
163ml/day / 12 hours = 1956ml/hr
The objective of using fluids is to replace deficits from previous losses, improve and maintain renal function, supply maintenance fluid requirements, and provide for ongoing losses (Lane, Dick. Cooper, Barbara. Turner, Lynn 2009)
Pre-medication:
The patient was given a pre-medication of Atropine (0.55ml) and Morphine (0.4ml 30mg) subcutaneously using aseptic techniques. Atropine and morphine (Wanamake, Boyce P. and Massey, Kathy Lockett 2010) work together as an analgesic and relax the patient before the procedure. These medications are chosen to help make a smoother anesthetic for the patient and a quicker recovery time. The patient was then returned to the cage to allow the pre-anesthetic to work. After the pre-med had started to work the patient became relaxed with a lowered heart rate and respiration rate.
(Photo copyright- Tiffany Mullany)
Induction:
The patient was induced using valium (0.8ml) and propofal (6.5mls) , (Wanamake, Boyce P. and Massey, Kathy Lockett 2010) it was slowly injected into the IV catheter port and the nurse held the patient until she became heavy and was under anesthetic. Once she was inducted she was intubated, which is passed dorsally over the maxilla and tied caudally around the ears at the base of the skull, then tied with an E.T tube tie. Once this was secure, the patient was connected to the anesthetic circuit and maintenance of anesthesia began. The cuff was inflated and listened closely for any leaks in the circuit.
Anesthesia:
The circuit used was a rebreathing F-circuit, which is appropriate for a patient of this size, as she is over 10kg. A 1L bag was used; it was calculated using this formula:
10ml x 16.3kg = 163
163 (TV) x 6 =978ml
A 1L bag = 1000ml so a 1L bag is only needed.
Tidal volume is the amount of air that passes in and out of the lungs in one normal respiratory cycle (Angela Gussey 2010). The pop-off valve must remain in the open position during surgery, allowing excess gas to dissipate through the scavenger line. An oespageal stethoscope was passed down the esophagus to monitor Heart rate and also can be good to listen to the respiration rate. Although there was machinery to be used in the monitoring, it is merely an aid rather than fully relying on it. The machines can read inaccurately and the animal is your best indication of anesthetic depth.
(Photo copyright- Tiffany Mullany)
A sphygmomanometer cuff was selected as size appropriate to the patient and attached just above the calcaneus and systolic and diastolic blood pressure were measured. Bell was monitored every 5 minutes and recorded on an anesthetic monitoring sheet. Heart rate, Respiration rate, mucous membrane colour, capillary refill time, palpebral/pedal reflex, blood pressure, amount of isoflurane were all measured, checked and recorded. Having an anesthetic monitoring sheet helps the nurse to be able to see how the patient is going under anesthetic and can show whether the patient stays on an even plane of anesthesia. Maintenance of 2.5% isoflurane and 2L/min oxygen was initiated as soon as the patient was connected to the anesthetic machine. The patient was maintained in a healthy plane of anesthesia, until completion of post-operative radiographs. The patient was then recovered with oxygen until coughing reflexes returned. Bell was then continuously monitored to make sure temperature returned to normal after surgery. She had the bair hugger and blankets until she warmed up.
Surgery:
On 09/08/11, Bell was placed under general anesthesia and an arterial catheter was placed in the right femoral artery to measure direct blood pressure. The dog was prepared for surgery and a ventral approach was made to the cranial cervical spine with transection of the right sternothyroideus muscle. A large articular left-sided fragment of the C2 vertebra was identified. The normal right articular section of C2 was stabilized to C1 using a single 0.0 45 threaded K-wire. The left-sided fragment was elevated and a bone fragment ventral to the spinal cord was removed. No other bone fragments were palpably evident. The left articular fragment was restored to anatomical position and stabilized using a 0.0 45 threaded K-wire. Three 2.4 mm bone screws were placed in the ventral aspect of the C1 vertebra and three 2.4 mm bone screws were placed in the ventral aspect of the C2 vertebra. A single 2.4 mm screw was placed through the caudal end of the left-sided fragment into the body of C2 for further stability. The screw heads were left approximately 6 mm above the bone surfaces. The entire area including the screw heads and pin ends was covered inpolymethylmethacrylate bone cement. Complete stability of the C1-C2 space was achieved. The longus colli muscles were closed using 0 PDS suture material. The sternothyroideus muscle was reopposed using 0 PDS suture material. The sternothyroideus muscles were opposed using 2/0 Monocryl suture material. Subcutaneous tissues were closed using 3/0 Monocryl suture material. Skin closure was routine.
A post-op radiograph similar to what Bell had performed in her surgery to stabilize the C2 vertebra.
Post-operative care:
Upon signs of anesthetic recovery (return of coughing reflexes, Elevated heart rate/respiration rate, etc.) the patient was extubated and wrapped in a warm blanket with the bair hugger, and temperature was checked regularly. This is to ensure the patient’s body temperature warms to normal body temperature (for a dog is around 38.3-38.5) without becoming hyper thermic (too hot) or hypothermic (too cold). Bell was kept on a drip with intravenous fluids for a few more hours post-op to accurately assure hydration after surgery.
Bell was administered these medications as required:
Fentanyl 500mcg 10ml injectable: 3 (dispensed)
Depending on pain levels: Fentanyl range is from 0.9 ml to 1.6 ml per hour and can be adjusted to suit patient’s needs.
Morphine Sulph 30mg inj 5x1ml: 0.32 (dispensed)
Give 0.32ml Sq for pain every 4-6 hours.
Kefzol 1g inj: 3.5(dispensed)
Give 3.5 ml Slowly IV every 8 hours overnight.
Rimadyl 75MG Chewable: 10(dispensed)
Give HALF a tablet TWICE daily until finished.
(Wanamake, Boyce P. and Massey, Kathy Lockett 2010)
After-care and discharge instructions:
Bell made an excellent recovery from her operation and following the procedure is ambulating normally with no evidence of the cervical pain. Bell was discharged on the 12/08/11, 3days after surgery with strict instructions that she has to be confined for six weeks followed by gradual return to normal activity. Toileting must be done on a harness and leash. Postoperative physiotherapy instructions were given to the owners at discharge. Suture removal will be in 10-14days at her normal clinic and radiographic assessment in a further six weeks.
Discharge summary:
Bell has had surgery to stabilize a fracture at the top of her neck. The surgery involved stabilizing the spine with bone screws and bone cement. Bell has recovered well from the surgery; however, it will be some time before all the symptoms have fully subsided. Bell still needs intensive nursing care to enable her to recover fully.
Please follow these instructions to ensure that Bell has a complete recovery from this surgery.
1. NO RUNNING, JUMPING, OR STAIRS FOR SIX WEEKS. Your dog should be on a harness and lead for urination and defecation.
2. Sutures need to be removed 10-14 days following the surgery. Please call if there is any swelling, discharge, or redness around the suture line.
3. Your dog seems able to empty the bladder normally but this needs to reassessed regularly.
4. Give the medications as prescribed.
5. Physiotherapy is an important part of your dog's recovery from the surgery. Physiotherapy starts with application of warm compresses over the suture line. Gently massage the muscles around the area while flexing and extending the limbs. More active exercise can be used as healing progresses.
6. Please don't hesitate to call if you have any questions or concerns.
Discussion:
The patient, other then the injury was healthy. The anesthetic went well with no further complications; she was stable throughout surgery and recovered very well. IV fluids were used to hydrate and compensate for any blood loss. The recovery and procedure was uneventful and the patient returned to health and good eating habits within 48hours of anesthesia.
Acknowledgements:
I would like to thank the staff a VSG for their advice and assistance throughout the duration of the case study.
Reference:
· American association for clinical chemistry (2001-2011)
· Callan, Robert J. DVM. MS. PhD. DACVIM (2002)
· Gussey, Angela (2010) “Anesthetic notes” Unitec, New Zealand.
· Jerram, Richard (2011) “Bell Hills” Veterinary Specialist Group, Auckland, New Zealand.
· Lane, Dick. Cooper, Barbara. Turner, Lynn. “BSAVA textbook of veterinary nursing”, 4th edition. Replika press pvt. Ltd. India.
· Matthews, Gary G. “Introduction to neuroscience” Blackwell publishing (2000), page 134
Retrieved from: www.google.com/books
· Shaw, Darcy H. “Small animal medicine”, Blackwell publishing, page 75
Retrieved from: www.google.com/books
· Wanamake, Boyce P and Massey, Kathy Lockett. “Applied pharmacology for veterinary technicians” fourth edition. Saunders publishing, Canada.
Appendix:
· ALP/ASP - any condition that affects bone growth or causes increased activity of the bone cells can often affect ALP levels in the blood. Temporary elevations are also seen in healing fractures.
· Thoracic auscultation- listening to the sounds within the body, it is a fundamental examination.
· Ataxia- is inco-ordination without paresis, spasticity or involuntary movement.
· Paresis- refers to partial loss of voluntary motor activity.
