34th Annual Scientific Meeting proceedings

Multiple different techniques reported for Lap- EHPSS attenuation. Some abdominal and some thoracoscopic. The most common shunt variety attenuated this way are splenophrenic and splenoportal. The most common technique reported is attenuation with thin film banding, but ameroid constrictor placement and complete ligation with suture has also been reported.

Most recent case series by Shigemoto J, et al. Laparoscopic treatment of congenital portosystemic shunts with portal pressure measurement and portal angiography in 36 dogs. Front Vet Sci. 2024 Feb 28;11:1291006 described portal pressure measurement. In this series, shunts were occluded completely or attenuated with thin film banding. Patients were positioned in Left lateral recumbency for epiploic & Right lateral recumbency for non-epiploic shunts. Portal pressure measurements and portal angiography were performed by accessing mesenteric (30) and splenic veins (6). Surgery time for right (25) recumbency cases = 55 min (28-120) and left (11) recumbency cases = 54 min (28-88). 33 patients were had shunts that were completely attenuated.

Intraoperative complications requiring conversion to an open technique occurred in 5/20 dogs in one report:

Bleeding (2), PSS not found (2), diaphragm perforation (1)

In another report, 1/36 had pneumothorax due to injury to the diaphragm.

Postoperative complications

Self-limiting portal hypertension in 3/20 dogs

Severe portal hypertension with surgical revision occurred in 1/20 dogs

1/36 developed postoperative hypernatremia and died 5 h post-procedure.

2/36 developed PANS

Blood work abnormalities improved in majority of dogs with follow-up.

Laparoscopic Hiatal Hernia repair
Multiple techniques described for Lap-HH. The most common is a Right lateral oblique recumbency with reverse Trendelenburg. A SILS port placed 2cm caudal to last rib on the left side and additional ports placed either medially or laterally. Barbed suture is usually used for the esophagopexy and hiatal closure is performed with simple interrupted sutures. A Left-sided gastropexy is also performed commonly.

Another technique is a 3-port technique in which a subumbilical telescope port is placed and instrument ports are then placed on the ventral midline 5–8 cm cranial to the umbilicus and in the left caudal quadrant. After port placement, the patient is rotated into right lateral recumbency.

Complications
Monnet study: Pneumothorax 3/8, Conversion in 4/8 (elective in 3)

Mayhew study: Pneumothorax leading to cardiac arrest in 1/18, Conversion 1/18, minor bleeding (9/18)

Singh study: Pneumothorax 5/9, Conversion in 2/9

Outcomes
Monnet E. Vet Surg. 2021 RS, in 8 dogs:

Median surgical time= 77.5min

Clinical signs reported at improved in 8/8 dogs

Mayhew P, et al. Vet Surg. 2021 PCT, in 18 dogs:

Median surgical time= 120min

Significant improvements in regurgitation associated with eating (78%) and with increased activity or excitement (69%)

Sliding hiatal hernia and GER severity scores improved significantly but SHH and GER frequency scores did not

Singh A, et al. JAVMA. 2023 RS, in 9 dogs

Median surgical time= 105min

Significant improvement in regurgitation following eating and during excitement/increased activity

Laparoscopic Diaphragmatic Hernia repair
When considering performing laparoscopic DH repair there are important physiologic factors. Thoracic pressures should not exceed 5mm Hg in dogs and 3mm Hg in cats. These procedures can be performed thoracoscopically or laparoscopically but Gasless or Lift-laparoscopy ideal.

Recent study by Brun et al Vet Med Sci 2022 utilized 3 Ports: a camera port on midline at umbilicus(12mm), instrument ports on the patient's right (5mm) and left (11mm). Sutures are then placed parallel to the xiphoid process and both costal arches lifted until clear visualization of the diaphragmatic defect achieved.

Complications with these repairs include tension pneumothorax, cardiac tamponade and re-herniation. Outcomes in case reports have been positive but larger prospective studies are required.

Laparoscopic Nephrectomy
Laparoscopic nephrectomy has been reported in multiple case reports and case series in dogs. The most common indication has been cancer, although reports of removal for kidney worms or pyelonephritis are also published. The author generally performs nuclear scintigraphy GFR studies before nephrectomy if more than 30% of kidney tissue appears normal on abdominal ultrasound to ensure the patient can do well after unilateral nephrectomy.

The positioning of the patient is dependent on the kidney being removed but the author usually placed the pet in an oblique lateral recumbency. Port placement can be multi-port (author’s preference) triangulated around the kidney to be removed on the lateral abdomen or single port. Hemostatic clips or a vessel-sealing device can be used to ligate the renal hilar vessels and the ureter. The ureter is usually ligated and transected as close to the ureterovesicular junction as possible and the kidney is placed in a specimen retrieval bag.

Results of one case series (Hart et al, Vet Surg 2021) revealed a median surgery time of 90 minutes (IQR 85-105). 1/7 dogs underwent an elective conversion to open laparotomy due to large tumor size. Median time to discharge was 31 hours (IQR 24-48) and no major perioperative complications occurred. All dogs survived to discharge.

Possible postoperative complications include hemorrhage, uroabdomen, neoplastic spread if kidney ruptures during manipulation. Outcome is usually based on tumor type or indication for nephrectomy.