Patient Preparation

Anesthesia Protocol

Abdominal Sonogram
Pregnancy Scan
Biopsy and Aspirate
Upper GI Endoscopy
PEG tube Placement
Bronchoscopy and Bronchial Aspirate


Anesthesia Protocol Used at the Clinic

Overnight fasting (but water ad lib) is sufficient for all the procedures except colonoscopy and upper GI endoscopy when gastric hypomotility is suspected. See Upper GI Endoscopy and Colonoscopy in this section for instructions for these situations.

Preanesthesia bloodwork (PCV, ALT, BUN, at minimum) should be performed for animals less than 6 years of age. For those 6 years of age and older, a CBC and chemistry profile are required. Chest radiographs should be performed in older patients, since not all animals with heart disease have murmurs. Additionally, pulmonary masses are relatively common and the presence of a mass may significantly alter further diagnostic plans. The only blood tests performed at the AUC are clotting times.

Isoflurane is used for induction and maintenance. A low dose of BAG may also be used in active larger dogs. Recovery is prompt and allows for these procedures to be performed during a 1½-hour office visit.

Should we feel that any significant risk is present, we will contact you prior to performing the procedure. Anesthesia time for an ultrasound-guided biopsy or endoscopy is ordinarily under 15 minutes. Animals are usually fully able to walk within 10 minutes.



Fasting is not necessary.

A 2" by 2" area of haircoat may be clipped behind each elbow. Please alert us if the owner prefers that the animal not be clipped.

A good Doppler study requires a cooperative patient. Sedation is used very infrequently, notably for extremely active puppies and very aggressive dogs. Very aggressive cats are scanned under light isoflurane anesthesia after having been induced in an induction chamber. Our experience with this technique has been excellent and we believe that the uncooperative feline cardiac patient is least stressed by this method.

Blood pressure, thoracic radiographs, and an EKG are necessary to complete the cardiac evaluation in most circumstances. Please supply us with those results if you have them. We will request permission to perform the EKG and BP if they are medically indicated and if those results do not appear on the Fax Referral Form. Notify us if you do not want these checked. Radiographs are not performed at The AUC.

It is essential that a CHF patient be stabilized prior to the echocardiogram. In confusing situations, please call to notify us that you are referring a severely dyspneic animal. Oftentimes, the complete echo and Doppler study will not be possible. A repeat visit to complete the study will be scheduled once the CHF is resolved.

All dyspneic patients with a large amount of pleural effusion will have the effusion removed prior to discharge. Please notify us if you would like a sample of the effusion fluid submitted to pathology.

Pericardiocentesis is most often performed with minimal to no sedation. This may be performed during a 1-hour office visit.

Many intrathoracic masses, such as cranial mediastinal, caudal mediastinal, and pulmonary masses, can be visualized by ultrasound and be biopsied. The masses that may not be visible are those in the medial part of a lung lobe. Bronchoscopy would be a more appropriate procedure in these cases. Please send the radiographs (both views) before the appointment if the situation is unclear.


Abdominal Sonogram

Fasting is not necessary unless a biopsy or other procedure requiring anesthesia is likely.

Examination of all the abdominal structures is standard; it does necessitate clipping the haircoat on each flank.

Sedation is rarely necessary. However, light isoflurane anesthesia may be required to obtain a good vascular scan, e.g., PSS cases.

It is possible to obtain a cystocentesis or a sample of abdominal effusion during the scan. Please notify us if you would like a sample of the fluid submitted to pathology.

Animals with large amounts of abdominal fluid will have the fluid removed prior to the scan. This improves the quality of the images obtained.


Pregnancy Scan

The ideal time to schedule a scan for pregnancy diagnosis is 26 to 28 days after the last breeding.

Although a gestational sac first becomes visible 18 days after conception, conception in some individuals may occur as late as 7 days after the last breeding. This is uncommon, but we have seen this occur in several German Shepherds and it could potentially occur in any breed.

A small area of haircoat (1/4" by 3") on the ventral midline may be clipped in thick-coated individuals. Permission from the owner is always obtained prior to clipping.

The charge for the pregnancy scan applies for walk-in visits at the Clinic. It does not include CareLink Transportation.

A pregnancy scan is a partial scan. The entire abdomen is not examined. Should this be necessary for the medical situation at hand, the usual charge for an abdominal sonogram applies.


Color Flow Assisted Ultrasound-Guided Biopsy and Aspirate

Overnight fasting is sufficient. Water need not be withheld.

All biopsies are performed with an 18 Ga. or 14 Ga. "Tru-Cut" type biopsy needle in an automatic biopsy gun (Biopty®).

Coagulation: A recent platelet count is required and our current minimum for biopsy is 90,000/UL. A fine-needle aspirate may be performed safely in more severely thrombocytopenic patients. Clotting times, PT, and aPTT will be performed here immediately prior to induction. Currently, our maximum PT allowable for biopsy is 2.5 seconds over high normal. Many cats with serious liver disease experience coagulopathy. Administration of Vitamin K for 2 to 3 days is effective in normalizing the clotting times enough to permit a safe biopsy in most cases. This holds true in both nonobstructive disease and obstructive disease.

Hypertension: Blood pressure will be checked prior to all renal biopsies. The peak systolic pressure at the time of biopsy must be less than 175 mmHg. In some situations, the blood pressure may be temporarily lowered with acepromazine to allow biopsy in those animals for whom delay is not possible. Ideally, amlodipine (Norvasc®) should be used to normalize the blood pressure prior to biopsy.

Almost any structure that can be imaged, and that is at least 4mm in diameter, may be biopsied. These include:

  • Chest: cranial mediastinal masses, pulmonary masses, and chest wall masses.
  • Abdomen: liver, kidney, spleen, pancreas, GI tract, prostrate, lymph nodes, masses.
  • Very small structures, vascular structures, and those located in difficult areas (e.g., retrobulbar masses) are often aspirated rather than biopsied. Although the diagnostic yield is not quite as good as a tissue biopsy, it may suffice in some situations.

Pathology Reports: The results are available within 2 business days of the procedure.

Please refer to our newsletter entitled "Color Flow Assisted Ultrasound-Guided Biopsy" for complete details concerning the technique used at The Clinic.


Upper GI Endoscopy

Recent radiographs (two views: VD and lateral abdomen) are required in all cases in which GI obstruction is possible. Obstruction is a relative contraindication for GI endoscopy. Linear foreign bodies, unless retrieved within approximately 4 to 6 hours of ingestion, are usually not retrievable via endoscopy due to penetration into the bowel wall during application.

Esophageal foreign bodies become increasingly difficult to retrieve endoscopically the longer they remain present. Please realize that suspected esophageal foreign body is a medical emergency and delay must be avoided.

Preanesthesia bloodwork and a CBC are recommended for patients less than 6 years of age. A recent CBC and profile are required for all patients 6 years of age and older.

Overnight fast, 8 hours as for general anesthesia, is adequate in most cases. The fast should be at least 12 to 18 hours in patients suspected to have delayed gastric emptying. This is most important in giant breed dogs and especially important in those which have had a gastropexy performed.

If it will not endanger or cause undue stress to the patient, please discontinue giving any steroids for 3 to 4 days prior to the endoscopy.

Please do not administer motility modifying agents (metoclopramide, cisapride, others) or sucralfate the morning of the procedure.



Colonoscopy requires an adequate colon prep in order to visualize the colonic mucosa and to examine the upper colon. If properly prepared, ileal biopsies may be routinely obtained. We realize that this is a difficult and unpleasant task. It is, however, very important for the procedure. Animals with diarrhea also need their colon prepped.

For dogs in reasonably good health, withhold food for 48 hours prior to the procedure. Administer a warm soapy water enema (approximately one liter per 30 lb. body weight, 30 ml to 60 ml for cats) the evening before the procedure, and again the morning of the procedure. For cats and debilitated, anorexic dogs, a 24-hour fast should suffice. If the animal will be transported by CareLink, please have your morning staff coordinate their work with the scheduled time for pick-up. Please notify us if the animal will not be ready to travel by 8:00 AM.


Gastrostomy (PEG) Tube Placement

The most common indications are feline hepatic lipidosis and animals with facial trauma. Any debilitated patient will benefit from the high level of nutrition that a PEG tube will provide. These include cats with chronic cholangiohepatitis and chemotherapy patients.

An overnight fast is necessary.

Cats with liver biopsy tissue that is light tan in color (suggestive of lipidosis) should have the tube placed at the time of the biopsy. A delay in nutritional support will adversely affect the patient's survival.

Anesthesia time is less than 5 minutes and cats in severe liver failure (e.g., total bilirubin over 10 mg/dl) have tolerated this protocol without complications.

The PEG tube is recommended in all anorexic, icteric cats with hepatic lipidosis. The recovery rate from this disease in our experience (over 150 cases) has been greater than 90%.

Cats with a chemistry profile suggestive of lipidosis but who also experience coagulopathy may have the PEG tube placed and forgo the liver biopsy. Although not ideal, outcomes have been favorable in several cases. If desired, the liver biopsy could be performed once adequate improvement of the coagulation profile has occurred.

Many cats with lipidosis do not have the typical enzyme changes described in the literature. Please keep an open mind when diagnosing feline liver disease.

A PEG Tube Information Sheet will be supplied. This details explicit instructions to help you and the owner manage the cat at home. Included are the exact caloric requirements needed, the recipe for the food mixture and additional helpful items we have collected from our previous cases.



Radiographs are often used to guide us to a focal lesion and are required in all cases. To be of good diagnostic quality, the films must be obtained with the animal under anesthesia. Please have the following views available. Without these views, the exam may be incomplete and important lesions could be missed.

  • Open mouth VD of maxillary sinuses with the jaw wide open and the hard palate parallel to the x-ray table. In a large breed dog, a DV may be more easily obtained with the cassette angled in the dog’s mouth. In a cat, dental film positioned in the cat’s mouth will give a more detailed radiograph than regular film.
  • AP of the frontal sinuses (with the animal in dorsal recumbency and looking up at the x-ray tube). Both frontal sinuses should be projected off the skull.
  • Open mouth lateral oblique of each side for examination of maxillary tooth roots.

Preanesthesia bloodwork is suggested in all cases and required for patients over 6 years of age. Chest films are required for animals over 6 years of age.

A platelet count is appropriate for cases exhibiting significant epistaxis. Coagulation times are thought appropriate only for those with severe epistaxis and are not checked prior to most rhinoscopic exams.

The rhinoscopy is performed with isoflurane anesthesia. Usually a complete exam with biopsies can be performed in 10 to 20 minutes. Please refer to Anesthesia Protocol Used at the Clinic at the beginning of this section for the description of our protocol.

In cats, usually 0.75 cm to 2.0 cm of the maxillary sinus can be visualized. In most dogs, the dorsal and ventral meatus can be entered and examined. The frontal sinus can be entered only if the pathologic process, e.g., neoplasia or fungal disease, has destroyed frontal bone. The nasopharynx is examined in all cases.

Biopsies are taken in all cases. Brushings have not been found very useful. Cultures are sometimes performed, but bacterial infection is usually secondary to another problem.

Any foreign body removed will be returned to your clinic for the owner’s interest.

If the indication for this procedure is unclear, please mail the films and appropriate history for our review prior to the patient’s visit. There is no charge for this screening except for return postage.


Bronchoscopy and Bronchial Aspirate

Recent radiographs, VD and lateral, are required in all cases. Please note that a lateral film alone is insufficient because the left and right middle lung lobes are obscured by the cardiac silhouette. Lesions in these lung lobes could easily be missed.

The bronchoscopy is performed with isoflurane anesthesia and takes approximately 15 to 20 minutes. Please refer to Anesthesia Protocol Used at the Clinic at the beginning of this section. Very dyspneic animals usually undergo this procedure quite safely as they are usually better oxygenated while on 100% oxygen and a low level of isoflurane than they are in room air.

If it will not endanger the patient, please discontinue any steroids and antibiotics for 48 hours prior to the bronchoscopy. Samples will be obtained for culture and cytology.

Should both bronchoscopy and laryngoscopy be required, the lower airway exam and bronchioalveolar lavage will be performed first. Lavage for deep lung cytology should not follow an upper airway exam for laryngeal paralysis. Contamination of the BAL samples with saliva will invariably occur.

Bronchial aspirate is the preferred procedure in cats and toy breed dogs with radiographic evidence of diffuse airway or pulmonary disease. It is less costly and less invasive for the patient.

If the indication for this procedure is unclear, please mail the films and appropriate history for our review prior to the patient’s visit. There is no charge for this screening other than for return postage.



Cystoscopy and urethroscopy are indicated to obtain a tissue diagnosis of lower urinary tract mucosa and masses in female dogs.

Although the proximal urethra can be visualized by abdominal ultrasound, the distal one-half to one-third can be examined only by endoscopy or by contrast radiography. In our experience, urethral transitional cell carcinoma is most often found at the proximal urethra or at the urethral papilla.

General anesthesia is required. Please do not withdraw antibiotic therapy prior to cystoscopy.

An ultrasound exam to evaluate the urinary tract anatomy will be performed prior to cystoscopy. In many cases, ultrasound-guided biopsy of the bladder wall will be less traumatic to the patient and will yield deeper and therefore higher-quality biopsy samples than cystoscopy. A guided biopsy may, therefore, be recommended after the scan.