Gastrointestinal Endoscopy Basics Pg. 1 Jeffrey K. Saur, DVM, DABVP In-Hospital Basic Training Opportunities Flexible Gastrointestinal Endoscopy Canine and Feline Syllabus Major parts of an endoscope Insertion tube Tube Bending section Distal tip Image guide objective lens Insufflation channel Accessory channel Irrigation channel Light guide objective lenses Handpiece Suction valve Air/water valve Accessory channel opening Up/down deflection knob Up/down deflection lock Left/right deflection knob Left/right deflection lock Eyepiece with ocular lens Diopter adjustment ring Umbilical cord Light guide connector Connector to suction pump Connector to air pump for insufflation Connector to water bottle for irrigation Pressure compensation valve: Remove cap and placard for use and routine cleaning Care of the endoscope Always handle the insertion tube carefully; avoid sharp bends, tight coiling, or accidental striking of the tube against hard surfaces The fingers should never manipulate the distal deflecting portion of the endoscope; the control knobs should be used to check the range of motion of the deflecting tip. Excessive force on the control knobs should always be avoided (make sure deflecting locks are off). Always use an oral speculum when passing the endoscope through the oral cavity of an anesthetized patient Never force instruments or pass foreign objects through the accessory channel. Pressure compensation valve: Remove red cap and placard from scope Red cap should be on scope ONLY For ethylene oxide sterilization Transportation/shipping (altitude changes of >2500 ft) Holding the endoscope Hold in left hand Left index finger controls suction valve Left index or middle finger can control air/water valve Left thumb controls up/down deflection knob Right hand Controls left/right deflection knob Inserts channel accessories Advances insertion tube Applies rotational torque to insertional tube Gastrointestinal Endoscopy Basics Pg. 2 Jeffrey K. Saur, DVM, DABVP Accessory channel and instruments “Disposable” instruments that are not compatible with endoscope may damage the accessory channel Instrument diameter should not exceed that recommended by the manufacturer Instruments should never be forced through the channel when resistance is felt Foreign objects should not be removed through the instrument channel: Instead, the entire endoscope should be removed from the patient once the object has been firmly grasped Before passing instruments through the deflected tip, the manufacturer’s recommendations should be reviewed. Irrigation: Fill the irrigation bottle 2/3 full with de-ionized or distilled water The use of de-ionized or distilled water will reduce the incidence of mineral deposits clogging the irrigation channel Cleaning, disinfection and sterilization A pressure check is done immediately after use to ensure that no leaks have developed. If a leak has occurred, DO NOT CLEAN THE ENDOSCOPE. Call Karl Stroz immediately. Avoid applying cleaning solutions to ocular lens and to diopter adjustment ring Next, organic material should be mechanically removed from all surfaces of the endoscope and other surfaces. All external surfaces should be wiped down with gauzes soaked in cleaning solution Remove suction valve and replace with cap. Cleaning solution is suctioned through the accessory channel to remove debris and soften any adherent debris. Cleaning brushes should then be passed through all channels several times to remove adherent debris before it has the opportunity to dry. Passing the cleaning brush through the channel rapidly may cause damage A back-and-forth scrubbing motion within the channel may cause damage The balance of the cleaning solution is then suctioned through the accessory channel A final rinse of de-ionized or distilled water is suctioned through the channel. All external surfaces are rinsed or wiped with de-ionized or distilled water. A final wiping down is done with 70% isopropyl alcohol-soaked gauze. Drying the endoscope Empty the irrigation bottle, and reattach Place cleaning cap on air/water valve Turn on air pump. This will expel the residual water from the irrigation channel. Then turn-on suction pump to air-dry the accessory channel Wipe down all external surfaces with clean, dry gauze. The air pump and suction should be left on 10 minutes before hanging scope for storage (longer if endoscope is stored in the case). Instruments The instruments should be rinsed well with warm water to remove debris. Place them next in an ultrasonic cleaner with cleaning solution Rinse the instruments with water Apply instrument milk, hang, and allow drying. Cold sterilization or ethylene oxide sterilization may be used. Autoclaving may be used if all parts are autoclave-safe A commercially available enzymatic cleaning solution designed for endoscopes and accessories is highly recommended Detergezyme (item # MX4500) Available through Med-Vet International (847) 680-3050 Does Karl Storz recommend the use of other solutions, such as dilute betadine, Nolvasan®, dish soap, or Cidex? All lens surfaces and light guide surfaces should be wiped with 70% alcohol to remove residual cleanser film that may compromise light and image transmission Gastrointestinal Endoscopy Basics Pg. 3 Jeffrey K. Saur, DVM, DABVP First of all, do no harm If too much air is insufflated, especially in small dogs and cats, the stomach may become quite distended, causing significant compromise of respiratory capacity. In extreme cases, venous return from the abdomen may also be compromised. When an examination is finished, suction as much air as possible from the stomach. During withdrawal, any fluid observed in the esophagus should be suctioned. Gastrointestinal Endoscopy Basics Pg. 4 Jeffrey K. Saur, DVM, DABVP Esophagogastroduodenoscopy (also referred to as gastroduodenoscopy, or endoscopy) When possible, patients should be fasted for at least 12 hours prior to the procedure. At least 24 hours should pass from the completion of any barium series. Residual barium should NOT be suctioned through the accessory channel. Barium is very adherent, and is difficult to remove. Known esophageal or gastrointestinal perforation is a contra-indication for esophagogastroduodenoscopy. Positioning of the patient and the scope The classic position for the patient undergoing endoscopy is left lateral recumbency. An oral speculum should ALWAYS be used for esophagogastroduodenoscopy The endotracheal tube should be tied in firmly either behind the patient’s head, or to the lower jaw (do not entrap the tongue in the tie) A long, flat surface in front of the patient is best. This allows the endoscope to be kept straight, which allows for better control, orientation, advancement and application of torque to the endoscope. Esophagoscopy Esophagoscopy is the method of choice for diagnosing disorders of the mucosa or causes of obstruction of the lumen, including esophagitis, stricture, foreign bodies, and neoplasia. Other disorders for which esophagoscopy is valuable are esophageal diverticulum, vascular ring anomaly, gastroesophageal intussusception, megaesophagus, hiatal hernias, and periesophageal compression. Terminology Dysphagia: Difficulty in swallowing Odynophagia: Pain on swallowing Ptyalism: Excessive salivation The scope is passed dorsally over the larynx, avoiding the piriform recesses laterally. Conditions: Megaesophagus Congenital megaesophagus: Occurs in several canine breeds, as well as Siamese cats Adult-onset megaesophagus Idiopathic Secondary to myasthenia gravis, polymyositis, peripheral neuropathies, CNS disease, dysautonomia, lead toxicity, hypothyroidism, or hypoadrenocorticism. General anesthesia makes the esophagus flaccid and dilated Esophagoscopy may be normal in animals with mild hypomotility A dilated esophagus without any insufflation is suspect. The presence of pooled fluid, froth, and/or food is more consistent with a diagnosis of megaesophagus. Esophageal diverticula: Large, circumscribed saculations of the esophageal wall, often containing fluid and/or ingesta. Vascular ring anomalies A persistent right aortic arch accounts for 95% of vascular ring malformations A stricture is present at the base of the heart, with dilation of the esophagus proximal, and normal esophageal diameters distal to the stricture. Pulsations are present at the level of the stricture Esophagitis The common causes of esophagitis include injury from gastroesophageal reflux during general anesthesia, esophageal foreign bodies, hiatal hernia, gastric emptying disorders, persistent vomiting, indwelling nasogastric tubes, ingestion of caustic irritants, and thermal injury from ingestion of overheated food (microwaved). Esophagitis caused by gastroesophageal reflux is related to the duration of mucosal contact with refluxed gastric acid, pepsin, bile salts and trypsin. Clinical signs from esophagitis secondary to anesthesia are usually seen 2-4 days post anesthesia. Lesions observed on esophagoscopy include mucosal erythema, hemorrhage, friability, irregularity, erosions, ulcers, pseudomembranes, indistensibility, and stricture. Esophageal stricture Gastrointestinal Endoscopy Basics Pg. 5 Jeffrey K. Saur, DVM, DABVP Visualized as a circumferential smooth ridge or ring of fibrous tissue Balloon dilation is the treatment of choice. Referral to a facility that is prepared to handle an esophageal perforation is recommended even though balloon dilation itself is a straightforward procedure. Esophageal perforation May occur during endoscopic removal of a foreign body, or stricture dilation. Clinical signs from esophageal stricture secondary to anesthesia are usually seen around 10 days post anesthesia. Clinical signs include anorexia, depression, odynophagia, fever, pain, cough, and/or dyspnea. Thoracic radiographs may demonstrate mediastinitis, pneumomediastinum, pneumothorax, soft-tissue emphysema, and pleural effusions. Endoscopy should NOT be performed in cases of known esophageal perforation Esophageal fistulas are congenital or acquired communications between the esophagus and the tracheobronchial tree, mediastinum, or pleural space. Hiatal hernias and gastroesophageal intussusception A sliding hiatal hernia is a protrusion of the abdominal segment of the esophagus and cardia region of the stomach through the esophageal hiatus into the thorax. A paraesophageal hiatal hernia occurs when a portion of the stomach (fundus) herniates through the hiatus into the caudal mediastinum along the caudal thoracic esophagus. A gastroesophageal intussusception is an invagination of the stomach into the lumen of the caudal esophagus. To reduce the intussusception, apply digital pressure to the cervical esophagus and maximally insufflate. The endoscope may be used to gently push the intussusception caudally. Monitor for respiratory compromise. Esophageal neoplasia Primary esophageal neoplasia is rare. Multiple biopsies from the same location should be obtained, especially if the surface is inflamed or necrotic. Firm masses may be biopsied by first stabbing repeatedly with a retractable injection/aspiration needle, then grasping with the biopsy forceps. Esophageal foreign bodies See foreign body section Gastroscopy Gastroscopy is a valuable tool for diagnosing primary gastric disorders including chronic gastritis, superficial gastric erosions, gastric foreign bodies, gastric motility disorders, ulcers, and neoplasia. Gastroscopy should be considered anytime there is hematemesis Preparation See notes at start of esophagogastroduodenoscopy Atropine and other anticholinergic drugs are not used unless they are required to maintain heart rate. Opioid drugs should not be used as they may increase pyloric tone. Anatomical terms Cardia Fundus Body Angularis (incisura angularis) Antrum Pylorus Greater curvature Lesser curvature During the initial examination, note any fluid or ingesta present, the ease with which the gastric walls distend with insufflation, and the gross appearance of the rugal folds and mucosa. Green or yellowish fluid may indicate reflux of intestinal contents into the stomach. Gastrointestinal Endoscopy Basics Pg. 6 Jeffrey K. Saur, DVM, DABVP To remove fluid, position the endoscope tip parallel to the fluid and gastric wall, and suction fluid. Avoid suctioning fluid with particulate matter. Debris can lodge in the accessory channel, clogging, and potentially damaging the channel. A retroflex view should be attempted/obtained to fully evaluate the cardia for lesions. To access the antrum, counterclockwise rotation on the up/down knob is used as the scope is advanced along the greater curvature. To access the pylorus, the pyloric opening is kept centered in the field of vision as the scope is advanced. Gentle, continuous pressure is applied to advance the scope through the pylorus. Once passed, clockwise rotation of both directional knobs may help advance the scope into the proximal duodenum. If this fails, a biopsy forcep may be passed through the pylorus, and then the scope advanced over the forcep into the duodenum. Monitor the patient as stretching and displacement of the gastric body and pylorus may elicit vagal stimulation resulting in a bradycardia. Biopsy techniques The stomach should be only moderately insufflated, allowing for grasping of prominent rugal folds. The biopsy forceps are advanced towards the mucosa at an angle of 45o to perpendicular to the mucosa. The biopsy forceps are advanced to a fold, opened, advanced, and closed. The forcep is withdrawn steadily, with the biopsy sample shearing-off as it enters the accessory channel. Only in cases of significant disease will the forceps “bite off” tissue. Biopsies of ulcers and erosions should be obtained from the margins. This reduces the amount of inflammatory or necrotic tissue obtained, reduces the possibility of a perforation, and maximizes the diagnostic tissue. Masses should be biopsied repeatedly and deeply. Chose a site that can be approached easily. Then, biopsy the same site repeated, digging into the mass. Conditions and diagnoses: In general, let the pathologist make the diagnosis. Gastritis: Mucosal erythema, mucosal irregularity, friability, hemorrhage, erosions, Helicobacter-associated gastritis: Pathologists will find this. Don’t sacrifice a biopsy for culture or for a urea slat test. Erosions and hemorrhages Erosions: A shallow defect in the mucosa that does not extend into the submucosa. Hemorrhage: Discrete petecchiae or bright-red streaks not associated with visible breaks in the mucosa. Associated with: stress lesions, critical illness, localized gastric trauma, ingestion of corrosives, radiation, drugs (especially NSAIDs), discrete ischemia, mast cell tumors, and idiopathic chronic erosions. Ulcers: An erosion that has breached the muscularis mucosa. Gastric polyps Gastric neoplasia: Adenocarcinoma is the most common gastric tumor in the dog. Lymphosarcoma is the most common gastric tumor in the cat. Duodenoscopy Regions: Proximal duodenum Proximal flexure Descending duodenum Major duodenal papilla Minor duodenal papilla (in dogs) Caudal or colic flexure Ascending duodenum Descriptors Gastrointestinal Endoscopy Basics Pg. 7 Jeffrey K. Saur, DVM, DABVP Cobblestone Erosion Erythema Fibrinous Fissures Grainy Granular Irregularity Proliferative Roughened Shaggy Swollen villi Velvety White discoloration Biopsy procedures Do not biopsy the major or minor duodenal papillae The biopsy forcep is opened, advanced to a specific target, closed, and retracted. The biopsy forcep is passed (blindly) until resistance is felt, retracted slightly, opened, advanced, closed, and retracted. The biopsy forcep is opened, advanced (blindly) against the mucosa until resistance is felt, closed, and retracted. Strips are often obtained in this manner. Depending on technique, a strip may break off, but can be retrieved by advancing the scope until it is visualized, then grasped with the biopsy forcep, and retracted. Conditions Inflammatory bowel disease Lymphangiectasia Swollen villi White discoloration Give 1-2 tablespoons of corn oil the night before the procedure to increase microscopic and macroscopic lesions. Intestinal parasites Neoplasia: Lymphosarcoma, adenocarcinoma, mast cell tumors, leiomyoma, leiomyosarcoma, fibrosarcoma, ganglioneuroma, and carcinoid tumors. Protein losing enteropathies: A special consideration needs to be taken with those patients having low total protein and/or low albumin. Some of these patients will have inapparent pleural effusion that can compromise anesthesia. Thoracic radiographs should be taken prior to anesthesia to assess for the presence of a pleural effusion. Gastroduodenoscopy This is the primary upper gastrointestinal endoscopy procedure. When generalized disease is suspected, the endoscope is rapidly advanced as far distally into the duodenum as possible. Inspection and biopsies are performed during withdrawal. By minimizing gastric manipulation and insufflation, the pylorus is more easily entered, thus reducing procedure time. Ileoscopy, colonoscopy and colonoileoscopy Colonoscopy Used to diagnose inflammatory disorders, neoplasia, and fungal infections. Preparation The patient is withheld from food for 36 hours. The patient receives a combination of oral lavage and cathartic solutions, and enemas (see attached colonoscopy preparation form). The patient is positioned in left lateral recumbency A digital rectal exam is performed to detect any distal lesions. The endoscope is then introduced into the rectum, using the digit to guide the scope tip past any folds in the rectum. The endoscope is advanced to the ileocolic junction. Gastrointestinal Endoscopy Basics Pg. 8 Jeffrey K. Saur, DVM, DABVP The feline cecum is a blind pouch. If advancing the endoscopy is not improving visualization, retract the scope and insufflate. The scope may already be in the cecum. A biopsy forcep may be advanced to push the mucosa away from the endoscope to allow for better visualization and recognition of the ileocolic valve. Ileoscopy Preparation is necessarily the same as it is for colonoscopy. Unless the approach angle to the ileocolic valve is straight, advancing the endoscope into the ileum can be difficult. Placing the patient in dorsal recumbency may help. Once the endoscope has been successfully passed into the ileum, the patient is returned to left lateral recumbency. The biopsy forcep may be passed through the valve, and then the endoscope advanced over it. Biopsies with colonoileoscopy Biopsies are obtained during withdrawal of the endoscope. Only moderate insufflation should be used. About 4-6 biopsies of the ileum should be obtained when possible. At least two biopsies should be obtained from each region: cecum, ascending colon, transverse colon, high descending colon, and lower descending colon. Multiple biopsies of specific lesions should be obtained and submitted in a separate container. When indicated, consider submitting a biopsy sample for Salmonella culturing, which can be an intracellular organism missed during fecal cultures. Post colonoileoscopy Suction excess air Theoretically antibiotics are not needed. Analgesics also are not needed. Conditions Colitis Strictures and obstructions Extramural obstruction: Smooth, normal appearing mucosa at level of obstruction Intramural obstruction: Similar to extramural, but often with some mucosal changes Mucosal disease is evident by irregular, roughened, highly inflamed mucosa. Neoplasia Approach based on clinical signs When vomiting is the chief presenting complaint, biopsies obtained by gastroduodenoscopy is indicated. Cats, though, may present with vomiting due to lesions anywhere in the small intestine, ileocecocolilc area, or proximal colon. Diarrhea may or may not be present. When chronic small bowel diarrhea and/or weight loss occurs, especially with panhypoproteinemia, biopsies should be obtained by gastroduodenoscopy and ileoscopy. When chronic, nonspecific diarrhea is present, biopsies should be obtained by gastroduodenoscopy and ileocolonoscopy. When hematochezia, chronic vomiting (especially cats), dyschezia, tenesmus, and constipation are present, colonoscopy is indicated. Foreign bodies Esophageal foreign bodies Most esophageal foreign bodies lodge at the thoracic inlet, the base of the heart, or at the lower esophageal sphincter. Clinical signs associated with an esophageal foreign body include salivation (which may include blood), regurgitation, odynophagia, dysphagia, retching, and anorexia. Gastric foreign bodies The most common clinical sign associated with a gastric foreign body is vomiting, which may be intermittent. Inappetence, anorexia, malaise, and abdominal tenderness may also be seen. General approach Obtain thorough radiographs. These may include cervical, thoracic and abdominal radiographs to evaluate for multiple foreign bodies. Gastrointestinal Endoscopy Basics Pg. 9 Jeffrey K. Saur, DVM, DABVP Thoracic radiographs should be evaluated for evidence of an esophageal perforation. Pneumomediastinum, pneumothorax, subcutaneous emphysema, and/or pleural effusions may be seen. Abdominal radiographs should also be evaluated for signs of a perforation. Evidence of free air or a peritoneal effusion may indicate a perforation, and surgery should be considered. Wood and most plastic foreign bodies are radiolucent, and will not be evident on radiographs. An air gastrogram may make these more evident, whereas a barium series may mask the foreign body, and subsequently interfere with an endoscopic inspection. When the history indicates, gastric and duodenal biopsies should also be obtained after a foreign body is removed. A prime example is when chronic vomiting was present prior to a known time of foreign body ingestion. Esophageal foreign bodies should be removed as soon as possible. Gastric foreign bodies should be removed if they are causing clinical signs, are unlikely to pass, are long and/or sharp, or are composed of toxic materials. Gastric foreign bodies that are best removed surgically include corncobs, rocks over 1-2 cm in diameter, balls, heavy objects, large pieces of cloth. Complications of endoscopic foreign body retrieval include perforation, lacerations, worsened impaction, pyothorax, pneumothorax, pneumomediastinum, and peritonitis. Equipment Very basic Alligator grasping forcep Snare Wire basket Overtube Bolt grabber Additional retrieval equipment: Two- or three-prong grasper Esophageal foreign bodies The patient is placed in left lateral recumbency. This positions the esophagus above the aorta. A foreign body should be retrieved, or pushed into the stomach. Some foreign bodies may only be pushed to the distal esophagus, but this then allows for a surgical approach through a gastrotomy to grasp and retrieve the foreign body through the lower esophageal sphincter. All of these methods are preferable to esophageal surgery. When lodged kibble is unexpectedly encountered, copious lavaging and patience may reduce the kibble to mush, and minimize any mucosal damage. A foreign body may be partially embedded in the mucosa. An overtube may help dilate the esophagus and aid in the removal of the foreign body. Fishhooks: Overtubes are very helpful. The fishhook may be drawn inside the overtube, or the prongs pulled tight against the overtube, which then allows for safe withdrawal of the fishhook. The overtube may be aligned snuggly against a lodged fishhook, and then forcefully thrust caudally to dislodge it. A deeply embedded fishhook may be retrieved through a combination of thoracotomy and endoscopy. The penetrating barb may be snipped off surgically, and the balance of the fishhook retrieved endoscopically. This eliminates the need of a full-thickness esophageal incision. Bolt grabbers (obtainable at auto parts and hardware stores) may be passed next to the endoscope to grasp large objects Make sure to file down any sharp edges on the grabbers to prevent injury to the patient and tears to the endoscope. The bolt grabber may also be advanced through a separate overtube. When perforation is possible, follow-up thoracic radiographs should be taken at 12 and 24 hours post-procedure to evaluate for pneumomediastinum, pneumothorax, and/or subcutaneous emphysema. Gastric foreign bodies Gastrointestinal Endoscopy Basics Pg. 10 Jeffrey K. Saur, DVM, DABVP No matter how long the foreign body has been present in the stomach, radiographs should be obtained immediately prior to anesthesia to insure that the foreign body hasn’t finally passed out of the stomach. Linear foreign bodies that extend through the pylorus may be gently tugged on. If resistance is felt, the patient should be taken to surgery. Pennies minted since 1982 contain a toxic level of zinc, which is rapidly freed by the action of stomach acid. Immediate removal by induced vomiting, endoscopy or surgery is essential. A penny, nickel and dime should be placed next to the patient and a radiograph taken. This can aid in determining which coin(s) might be in the stomach. A folded towel may be placed under the coins to approximate the thickness of the body wall and fat. This may help in maintaining the same degree of magnification that occurs based on the distance between the subject and the film plate. A lot of nuts and bolts are zinc-coated, and should also be removed immediately. Bolt grabbers (obtainable at auto parts and hardware stores) may be passed next to the endoscope to grasp large objects Make sure to file down any sharp edges on the grabbers to prevent injury to the patient and tears to the endoscope. The bolt grabber may also be advanced through a separate overtube. Once a foreign body has been retrieved, the entire stomach and duodenum should be inspected for any remaining foreign material for the procedure to be considered completed. Duodenal foreign bodies Linear foreign bodies may be gently tugged on. If resistance is felt, immediately proceed to surgery. A lot of duodenal foreign bodies have the aggravating habit of advancing distally at the approach of the endoscope. This is partially due to the air insufflation. This expands the lumen, which then frees the foreign body and allows the air to push it or peristalsis to carry it distally, until it is out of reach. Those duodenal foreign bodies that stay put are often so firmly lodged that surgery must be used to retrieve them. Gastrointestinal Endoscopy Basics Pg. 11 Jeffrey K. Saur, DVM, DABVP COLONOSCOPY PREPARATION (Or, Things Are Looking Up) The following is a recommended procedure and timetable for preparing a patient for colonoscopy. Oral lavage Two days prior to procedure Confine Start fast (water OK) in evening after highly-digestible meal (I/D, A/D) Open magnesium citrate, pour in pan, and allow de-fizzing overnight One day prior to procedure Have owner drop-off pet first thing in the morning Water OK at all times during preparation, but DO NOT FEED HOSPITALIZE UNTIL AFTER PROCEDURE IS DONE The lavage solution should produce a copious, unpredictable diarrhea that can ruin a client’s house, carpets, and a good client-Veterinarian relationship Give Reglan 0.1 mg/LB IM at admission 15 minutes later, administer Magnesium citrate 10 - 15 cc/LB PO Dogs: May need to stomach tube Cats: Nasogastric tubes work well Place cat in cat bag, apply cat muzzle Place 2-3 drops ophthalmic topical anesthetic down left nostril Apply light layer of lubricant to 3 1/2 or 5 fr red-rubber feeding tube Lidocaine jelly works best K-Y Jelly OK Slowly advance feeding tube through nostril while firmly holding the cat’s head with other hand (1-2 technicians holding cat down in bag) When full length of feeding tube is in, slowly flush tube with 3 - 6 cc NaCl to make sure you’re in the esophagus, not the trachea. Slowly administer fluid through nasal tube Pinch off tube, then gently and slowly remove tube Unmask and unbag the (probably upset) cat Take dogs for frequent walks throughout day Make sure cats have ample litter box and litter In late afternoon, repeat Reglan IM 15 minutes later, Use Go-Lytely at 10 – 15 cc/LB PO Day of procedure Dogs Give gentle, warm water enema of 10 - 15 cc / LB first thing in the morning Repeat in 2 hours Cats: Give gentle, warm water enema of 9 cc / LB first thing in the morning Repeat in 2 hours If patient appears to have “cleaned itself out”, place in clean cage and wait for time of procedure Colonoscopies generally are done between noon and closing Anesthetic protocol as indicated by the patient’s overall health status NO NITROUS Narcotics should be avoided as they may cause intestinal spasms and make it more difficult to enter the ileum Gastrointestinal Endoscopy Basics Pg. 12 Jeffrey K. Saur, DVM, DABVP COLONOSCOPY PREPARATION Enemas I recommend doing two enemas the morning of the procedure after having done the usual oral lavage preparation the day before, especially if little or no diarrhea has been produced, or if feces are still evident on rectal: Enema: Warm water only Lactulose may also be used : 1 part per two parts water Pass large French feeding tube to level of last rib Administer prescribed amount of enema mixture rectally Return to cage, or take dogs for walks I find it helpful to hold the cat’s tail firmly over the rectum and between its rear legs until the cat is placed safely back in its cage (small dogs as well) In general, I have found using only an enema as preparation inadequate in that there is usually fresh ingesta entering the upper colon during the colonoscopy. Hints on using the Go-Lytely lavage solution This is available by prescription in a powdered form in a 4 liter container. Obviously our little patients are not going to require the whole jug. I recommend making up an appropriate amount in a separate jar (like 500cc for a cat) and preserving the balance for future procedures. If you have a gram scale, Weigh the powdered contents Record total weight of powder, and the amount to make 500cc when combined with water, which will be 1/8th of the total weight of the powder Record amount in grams to make 500cc on jug Return balance to jug and store Mix appropriate number of 500cc aliquots for the job in a separate container If you don’t have a gram scale Pour powder into clean, very dry 60cc syringe or appropriately sized measuring cup Record total volume of powder, and the amount to make 500cc when combined with water, which will be 1/8th of the total volume of the powder Record amount to make 500cc in units of measure on jug (cc, Tbsp, cups, etc.) Return balance to jug and store Mix appropriate number of 500cc aliquots for the job in a separate container Gastrointestinal Endoscopy Basics Pg. 13 Jeffrey K. Saur, DVM, DABVP References Chamness JJ: Endoscopic instrumentation. 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In Tams TR, editor: Small Animal Endoscopy (2nd ed.): Mosby, Inc., St. Louis. pp 97-172. 1999. Willard MD: Colonoscopy. In Tams TR, editor: Small Animal Endoscopy (2nd ed.): Mosby, Inc., St. Louis. pp 217-245. 1999. Willard MD: Rare esophageal diseases that are not rare if you look for them: Proceedings of the 18th Annual ACVIM Forum. pp 33-35. 2000. Zoran D: Protein-losing enteropathies. Proceedings of the 75th Annual Western Veterinary Conference. Vet-122. 2003.