Page 480 - WSAVA2018
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 25-28 September, 2018 | Singapore
owners to request for minimally invasive procedures.
I’ve described the desirable advantages to kitty keyhole sur- what are the disadvantages? One drawback is the initial financial outlay and training required to acquire the skills and safely perform these procedures in feline patients. Anoth- er drawback is the overly compliant abdominal cavity in the cat, coupled with a small working space for triangulation and reduced depth perception which can make abdominal access more challenging compared to dogs.5,6 In addition, there’s a need to development of a ‘6th sense’ due to lack of direct tac- tile feedback by relying on instruments as an extension of our fingers. For example, the use of a palpation probe can be used not only to manipulate organs but it’s also used palpate textures and ‘ballot’ organs (e.g. gall bladder for signs of inflammation/ thickness) as additional information beyond gross appearance. The key to success to making the transition over to ‘the other side’ is to be patient and taking a step-by-step approach when acquiring new skills, receiving formal tuition from experienced endoscopists (e.g. university training centres), and refrain from being too ambitious when being released into the real world!
Indications for Diagnostic Laparoscopy
Full evaluation of abdominal organs for signs of disease, biopsy liver, pancreas, lymph nodes, kidney, small intestine (‘laparoscopic-assisted’ full-thickness), abdominal mass evaluation, and cholecystocentesis.5,6
Cardiovascular instability, inappropriate equipment, inexperienced/untrained surgeons, diaphragmatic hernia, extreme obesity, septic peritonitis, adhesions, coagulopathy, any condition in which conventional surgical intervention is indicated.
History/Clinical Examination/Pre-surgery Diagnostics:
As for any surgical candidate, a full clinical history, clinical examination, and appropriate pre-surgery diagnostics should be performed prior to any exploratory intervention. Ultrasonography by a skilled imager is extremely useful to help isolate a specific area, and extent, of disease. Diagnostic imaging is considered to be a complementary part of any medical investigation and should ideally be considered prior to any laparoscopic assessment. A full clotting profile should also be performed prior to surgery (PT, APTT, and total platelet count); however, if this is not possible, then performing an activated clotting time, total platelet count and buccal mucosal bleeding time should be performed as a bare minimum. Despite the latter recommendation, clinical experience (and experience of fellow colleagues) suggest that abnormal bleeding times may not necessarily preclude performing diagnostic laparoscopy as abnormal clotting times do not always correlate with excessive bleeding at biopsy sites. There are studies in human medicine that indicate that in vitro coagulation tests do not accurately predict the probability of hepatic bleeding times.8.9
Liver Biopsy
Once the abdomen has been thoroughly examined, a suitable area on the liver is selected for collecting a biopsy using a 5mm laparoscopic ‘clamshell’ biopsy instrument.5-7 This can be placed through the same accessory cannula as the blunt probe, thus avoiding the need to place an additional port. These types of instruments obtain much larger specimens compared to fine
needle or core biopsy samples. If excessive bleeding occurs, the palpation probe is used to apply direct compression over the biopsy site until a clot has formed. If bleeding is still uncontrolled then laparoscopic forceps can be used to place a piece coagulation material into the biopsy defect.
Pancreatic Biopsy
The pancreas can be biopsied from the distal-most portion of the right limb for diffuse disease, or directly into a lesion, using a 5mm endoscopic biopsy punch forceps. It’s vital to avoid the pancreatic ducts in the proximal portion of the limb, next to the duodenum. The same technique for collecting a liver biopsy, applies to pancreatic biopsies.
Bile aspirates for cytology and culture/sensitivity are important when performing gastrointestinal investigations in cats, particularly those suspected of having triaditis. Laparoscopic cholecystocentesis is considered safe and easy to perform. The author will typically use a spinal needle (18-20G x 3-6” or 20-22G depending on fluid viscosity) with an inner stylet that can be removed once the lumen of the gall bladder has been penetrated. The needle entry site on the external abdominal wall should be identified by ballottement visualised through the endoscope and should be caudal to the diaphragm. Depending on the intracystic pressure, it can be challenging to penetrate the wall with the needle. A quick forceful ‘jab’ will usually facilitate entry. Complete aspiration of all contents should be attempted to reduce the risk of bile leakage and peritonitis. In the author’s experience, this is a rare occurrence.
Intestinal Biopsies
Biopsy of the small intestine is usually performed using a laparoscopic-assisted technique. A ‘mini-laparotomy’ is usually performed by exteriorising a small bowel segment through a port incision. As an alternative approach in cats (compared to dogs), the author will often perform intestinal/lymph node biopsies at the end of the exploratory procedure using a wound retractor (Alexis 2cm-4cm)10 placed in the caudal camera port. Because pneumonperitoneum will be lost, it is advisable to perform intestinal biopsies at the end of the procedure.
Post-operative care
Most cats (if no intestinal biopsies were obtained), will often be discharged the same day as the procedure. If intestinal biopsies were collected, then overnight observation is advised as per open surgery until the patient is eating with no signs of post- operative complications such as intestinal wound dehiscence.

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