Biomechanical and Histological Evaluation of a Laparoscopic Stapled Gastropexy Technique in Dogs

The biomechanical holding strength and histological characteristics of a laparoscopic stapled gastropexy (LG) adhesion were compared with that of an incisional gastropexy (IG) adhesion. An LG was performed in 14 dogs and an IG was performed in six dogs. During the LG procedure, the abdomen was insufflated with carbon dioxide and three cannulae were placed in the caudal aspect of the right side of the abdomen. A 35 mm laparoscopic stapler was used to staple the gastric antrum to the adjacent right lateral abdominal wall. The IG procedure was performed through a ventral midline celiotomy. A 35 mm IG was made by apposing the gastric antrum to the adjacent right lateral abdominal wall with two continuous rows of suture. Half of each group of dogs was euthanatized at 7 and 30 days after surgery. The mean tensile load to failure at 7 days was 44.86 ± 18.54 N for the LG group and 85.33 ± 23.59 N for the IG group ( P <.05). At 30 days the values were 72.93 ± 18.01 N for the LG group and 71.17 ± 12.11 N for the IG group ( P =.41). The gastropexy adhesions in the 7-day postoperative group contained variable amounts of fibrin, hemorrhage, mononuclear cell inflammation, loose fibrovascular tissue, and mature collagenous connective tissue. Adhesions in the 7-day postoperative group were divided subjectively into three histological subgroups based on the relative amounts of mature connective tissue within the adhesion. The LG and IG adhesions were randomly distributed among these subgroups ( P = 1.0). Adhesions in the 30-day postoperative group contained well-organized fibrous connective tissue. No difference in the amount of connective tissue could be detected histologically in the LG or IG adhesions. Complications with the LG procedure included stomach perforation (2 cases), splenic puncture (2 cases), and subcutaneous emphysema (4 cases).     

Ultrasonographic comparison of adhesions induced by two different methods of gastropexy in the dog

Ultrasonography was used to compare adhesions induced by two different methods of gastropexy in 16 dogs. An incisional gastropexy technique was used in eight dogs (group 1) and a 'modified' gastropexy technique in the remaining eight (group 2). The length and thickness of the gastropexy and the peristaltic activity of the stomach were measured ultrasonographically and compared between groups. Measurements for the two groups were taken in the early postoperative interval (two to four days), intermediate postoperative interval (eight to 20 days) and late postoperative interval (57 to 79 days). Both techniques were equally successful in forming permanent adhesions at two months postoperatively and there was no recurrence of gastric dilatation and volvulus. The length and thickness of the gastropexy were similar for both groups at two months postoperatively and there were no surgical complications with either technique. The modified gastropexy provides a technique that can easily be performed by a single surgeon , with no increased operative time or duration of anaesthesia, and with the formation of a permanent adhesion.     

A Comparison of Laparoscopic and Belt-Loop Gastropexy in Dogs

A simplified technique for laparoscopic gastropexy (group 1) was compared to belt-loop gastropexy (group 2) in eight adult male dogs randomly divided into two groups of four dogs each. Our hypothesis was that a satisfactory laparoscopic gastropexy would approximate the strength and operative time required for belt-loop gastropexy. Operative time, surgical complications, postoperative morbidity, gross and histological appearance, radiographic microvascularization, and maximal tensile strength were measured and compared between the two groups. All dogs recovered from surgery. No morbidity was associated with either procedure. The mean (±SD) duration of surgery was 69.75 ± 7.23 minutes for group 1 and 58.75 ± 7.63 minutes for group 2. Fifty days after surgery, the microvascular appearance of the gastropexy site was similar for both groups. Blood vessels were observed within each seromuscular flap but vascular ingrowth to the abdominal musculature was observed in only two dogs, one from each group. The maximum tensile strength at 50 days was 76.55 ± 22.78 for group 1 and 109.21 ± 22.29 N for group 2. Differences between surgical duration and maximum tensile strength were not statistically significant ( P >.05). Histologically, all gastropexies consisted of an adhesion composed of dense fibrous connective tissue. The results of this study indicate that laparoscopic gastropexy provides a minimally invasive alternative to open abdominal prophylactic gastropexy in dogs.     

Comparison of complications of percutaneous endoscopic versus surgically placed gastrostomy tubes in 42 dogs and 52 cats

Dogs and cats that had a percutaneous endoscopic gastrostomy (PEG) tube or surgically placed gastrostomy (SPG) tube inserted were retrospectively analyzed to compare complication rates and the severity of complications. Complication rates and severity scores were not significantly different when the PEG tube group was compared to the SPG tube group in either dogs or cats. Only when data from dogs and cats were combined did PEG tubes have a significantly higher complication rate and significantly greater complication severity scores.     

Biomechanical Evaluation of Gastropexy Techniques in the Dog

The relative strength of adhesions created by three different gastropexy techniques in dogs was evaluated two and six months following surgery. Tube gastrostomy formed a stronger adhesion (p>.001) when compared with simple gastropexy and permanent gastropexy two months after operation. In a smaller number of animals examined at six months, no difference in strength was noted between permanent gastropexy and tube gastrostomy.     

Ultrasonographic evaluation of adhesions induced by incisional gastropexy in 16 dogs

A study was undertaken to evaluate the use of ultrasonography to assess the gastropexy site for permanent adhesion in clinical cases. Two groups, each comprising eight dogs, were studied, all 16 cases undergoing decompression, anatomical repositioning of the stomach and an incisional gastropexy after gastric dilatation-volvulus (GDV). Group 1 was set up as a prospective group in which ultrasonographic examinations were performed three times (mean three, 12 and 67 days) after surgery to evaluate the gastropexy region. The gastropexy site was assessed ultrasonographically at only one stage (mean 449 days after surgery) in the group 2 dogs. Criteria used to assess the usefulness of the ultrasonographic evaluation included the ability to identify the gastropexy site, to obtain measurements of the length and thickness of the site and to assess the ultrasonographic appearance of the different gastric wall layers. The average number of peristaltic contractions and degree of gastric filling were also evaluated. The fixation between the stomach and the abdominal wall was easily detected in all 16 cases. Ultrasonography proved to be a simple and non-invasive technique to assess the permanency of the gastropexy. The Incisional gastropexy was relatively easy to perform and induced permanent adhesions in all 16 dogs, without recurrence of GDV.     

Prospective Evaluation of Two Intracorporeally Sutured Prophylactic Laparoscopic Gastropexy Techniques Compared with Laparoscopic-Assisted Gastropexy in Dogs

Objective— To report technique, surgical time, complication rate, and postoperative activity in dogs undergoing 2 intracorporeally-sutured total laparoscopic gastropexy (TLG) techniques compared with a laparoscopic-assisted gastropexy (LAG) technique.
Study Design— Randomized clinical trial.
Animals— Dogs (n=30) weighing >25 kg.
Methods— Dogs were randomly assigned to 1 of 3 groups. Two TLG techniques were performed using a median 3 portal technique. One of 2 suturing techniques was used to approximate corresponding incisions made in the stomach and body wall; using intracorporeal hand-suturing or a suture-assist device (Endostitch^™). In a 3rd group, a previously reported LAG technique was used. All dogs had an activity monitor placed for 7 days pre- and postoperatively. Linear regression analyses were performed to evaluate the association of surgical procedure on gastropexy time and the percentage change in activity counts.
Results— Median gastropexy time was 28 minutes (range, 20–41 minutes) for LAG, 48 minutes (range, 39–61 minutes) for the hand suture TLG technique, and 56 minutes (range, 30–90 minutes) for the Endostitch^™ TLG technique. LAG was performed faster than TLG ( P <.05). LAG dogs had a greater decrease in postoperative activity than TLG dogs ( P =.005); however there was no difference in surgical time or postoperative activity between TLG techniques.
Conclusions— TLG can be performed safely and effectively in dogs and although it takes longer, it has less impact on postoperative activity compared with LAG.
Clinical Relevance— TLG techniques may have advantages over LAG as measured by a greater willingness of dogs to move around postoperatively.     

Tube gastrostomy in dogs

Tube gastrostomy was performed in 19 dogs over a period of 36 months. Indications for tube gastrostomy included non-oral feeding for the management of oesophageal injuries (nine cases) and dysphagia resulting from oral or pharyngeal trauma (two cases) and decompression and, or, gastropexy for gastric diseases including gastric dilatation volvulus (four cases), gastric outflow diseases (three cases) and gastric neoplasia (one case). All the tubes were placed surgically and left in situ for periods of up to 14 days. Feeding was by frequent bolus administration of a proprietary enteral food initially followed by homogenised commercial dog food. The tubes were readily managed and patency maintained in all cases. Gastric stomata granulated within three days of tube removal. Fourteen dogs recovered and returned to normal oral feeding while three died as the result of their presenting condition. A fourth was euthanased four months after surgery because of recurrence of a gastric malignancy. This review indicates that surgically placed tube gastrostomy is readily performed and is an effective means of providing non-oral alimentation and, or, gastric decompression.     

A Laparoscopic‐Sutured Gastropexy Technique In Dogs: Mechanical and Functional Evaluation

Objective— To describe a laparoscopic‐sutured gastropexy technique in dogs and evaluate the tensile strength of the adhesion and effects on gastric function. Study Design— Experimental study. Animals— Female beagle dogs (n=7). Methods— A laparoscopic‐sutured gastropexy technique was evaluated by ex vivo tensile distraction tests 10 weeks after surgery. The effect of the adhesion on gastric emptying, mucosal permeability, and systemic inflammation were evaluated by monitoring the C‐reactive protein (CRP) and sucrose permeability, and by radiographic evaluation of gastric emptying 2 weeks before and 10 weeks after surgery. Results— Mean (±SD) tensile force to disrupt adhesions was 51.1±16.4 N. There was no significant postoperative increase in CRP concentration or change in sucrose permeability. The area under the curve representing the postprandial decrease in gastric radiographic area increased by 11% after gastropexy. Conclusions— This laparoscopic gastropexy technique had appropriate mechanical and functional characteristics with limited morbidity. Clinical Relevance— This laparoscopic‐sutured gastropexy provides adhesion strength comparable with other gastropexy techniques tested at 10 weeks postoperatively. Only minor changes in gastric emptying were observed 10 weeks after surgery.     

Complications and outcomes associated with use of gastrostomy tubes for nutritional management of dogs with renal failure: 56 cases (1994-1999)

OBJECTIVE: To evaluate complications and outcomes associated with use of gastrostomy tubes in dogs with renal failure. DESIGN: Retrospective study. ANIMALS:56 dogs. PROCEDURE: Medical records were reviewed for dogs with renal failure that were treated by use of gastrostomy tubes. RESULTS: Mean +/- SD BUN concentration was 134 +/- 79 mg/dl and mean serum creatinine concentration was 9.0 +/- 3.8 mg/dl. Low-profile gastrostomy tubes were used for initial placement in 10 dogs, and traditional gastrostomy tubes were used in 46 dogs. Mild stoma-site complications included discharge, swelling, erythema, and signs of pain in 26 (46%) of dogs. Twenty-six gastrostomy tubes were replaced in 15 dogs; 11 were replaced because of patient removal, 6 were replaced because of tube wear, and 3 were replaced for other reasons. Six tubes were replaced by low-profile gastrostomy tubes. Gastrostomy tubes were used for 65 +/- 91 days (range, 1 to 438 days). Eight dogs gained weight, 11 did not change weight, and 17 lost weight; information was not available for 20 dogs. Three dogs were euthanatized because they removed their gastrostomy tubes, 2 were euthanatized because of evidence of tube migration, and 1 died of peritonitis. CONCLUSIONS AND CLINICAL RELEVANCE: Gastrostomy tubes appear to be safe and effective for improving nutritional status of dogs with renal failure.     

The effect of Hetastarch (670/0.75) in vivo on platelet closure time in the dog

Objective – To evaluate the effect of 6% hydroxyethyl starch (HES) solution in vivo, with an average molecular weight of 670 kDa and degree of substitution of 0.75, on canine platelet function.
Design – Prospective, controlled-experimental study.
Setting – University of California, Davis, Veterinary Medical Teaching Hospital.
Animals – Seven healthy employee-owned dogs.
Interventions – Seven dogs were included in the treatment group. Four of these dogs also served as the control group. Platelet closure time (CT) was measured using a platelet function analyzer and collagen/ADP cartridges. Dogs were given 20 mL/kg of either sodium chloride 0.9% (control group, n =4) or HES (treatment group, n =7) IV over 1 hour. CT was measured before the infusion, and at 1, 3, 5, and 24 hours after the start of the infusion.
Measurements and Main Results – There was a significant change over time from 0 to 24 hours ( P <0.001), a significant difference between groups across time ( P <0.001), and a significant group-by-time interaction ( P =0.007). At 3 hours, mean CT for the treatment group was 122.3±18.1 seconds, which was significantly different ( P <0.001) from the control group (71.0±3.5 s). At 5 hours, mean CT for the treatment group was 142.7±33.9 seconds, which was significantly different ( P =0.001) from the control group (75.0±8.6 s). Mean CT at 24 hours was within the reference interval for both the control and treatment group (66.0±2.9 and 81.8±11.9 s, respectively); however, CT in 3 individual dogs in the treatment group at this time point remained prolonged.
Conclusions – A clinically relevant dose of HES 670/0.75 prolongs CT in dogs for up to 24 hours. This may be due to platelet dysfunction in addition to the effects of hemodilution, and therefore, may increase the risk of bleeding.     

Effect of Thyroxine Supplementation on Glomerular Filtration Rate in Hypothyroid Dogs

Background: Glomerular filtration rate (GFR) is decreased in humans with hypothyroidism, but information about kidney function in dogs with hypothyroidism is lacking.
Hypothesis: Hypothyroidism influences GFR in dogs. The objective of this study was to assess GFR in hypothyroid dogs before implementation of thyroxine supplementation and after re-establishing euthyroidism.
Animals: Fourteen hypothyroid dogs without abnormalities on renal ultrasound examination or urinalysis.
Methods: Blood pressure and GFR (measured by exogenous creatinine clearance) were measured before treatment (T0, n = 14) and at 1 month (T1, n = 14) and at 6 months (T6, n = 11) after beginning levothyroxine supplementation therapy (20 μg/kg/d, PO). The response to therapy was monitored at T1 by measuring serum total thyroxine and thyroid stimulating hormone concentrations. If needed, levothyroxine dosage was adjusted and reassessed after 1 month. Statistical analysis was performed using a general linear model. Results are expressed as mean ± standard deviation.
Results: At T0, the average age of dogs in the study group was 6.3 ± 1.4 years. Their average body weight decreased from 35 ± 18 kg at T0 to 27 ± 14 kg at T6 ( P < .05). All dogs remained normotensive throughout the study. GFR increased significantly with levothyroxine supplementation; the corresponding results were 1.6 ± 0.4 mL/min/kg at T0, 2.1 ± 0.4 at T1, and 2.0 ± 0.4 at T6 ( P < .01).
Conclusion: GFR was <2 mL/min/kg in untreated hypothyroid dogs. Re-establishment of a euthyroid state increased GFR significantly.     

Clinical evaluation of a right-sided prophylactic gastropexy via a grid approach

A new technique is described for a prophylactic incisional gastropexy via a right-sided grid approach (i.e., minilaparotomy). A pilot study showed comparable tensile strength between a traditional ventral midline approach and the grid approach. Six client-owned dogs were selected for the procedure. Four weeks postoperatively, a barium gastrogram was performed to assess stomach/gastropexy position. Complications included a seroma and postoperative discomfort. This technique should be considered for any at-risk breed that is not overweight. The right-sided grid approach to a prophylactic gastropexy was less invasive than a ventral midline approach and resulted in a stable gastropexy at 4 weeks postoperatively in five of six dogs.     

Transcatheter Atrial Septal Defect Closure with the AMPLATZER® Atrial Septal Occluder in 13 Dogs: Short- and Mid-Term Outcome

Background: Transcatheter atrial septal defect (ASD) closure in the dog was first reported in 2005.
Objectives: Describe the technique and both short- and mid-term outcome of transcatheter ASD closure with the Amplatzer^® atrial septal occluder (ASO).
Animals: Thirteen client-owned dogs with ASD.
Methods: Records of the initial 13 dogs in which transcatheter ASD closure was attempted at Texas A&M University were reviewed.
Results: All dogs had hemodynamically relevant septum secundum ASD. Two dogs had concurrent congenital abnormalities. ASOs were deployed in 13 dogs and released in 12. Eleven were released by a right jugular approach and 1 by a transatrial approach through a right lateral thoracotomy. Transthoracic echocardiographic estimates of ASD size were 14.0 ± 5.4 mm (mean ± 1 standard deviation) with a range of 7–22 mm. Accidental right atrial release occurred in 1 dog and embolization after release occurred in 2 dogs. Transcatheter ASD closure was successful in 10 dogs. Transthoracic color Doppler echocardiography the day after ASD closure indicated complete occlusion in 5 dogs, trivial to mild residual shunting in 4 dogs, and moderate residual shunting in 1 dog. Follow-up echocardiograms (mean of 12.4 ± 7.4 months postprocedure) were available for 9 dogs. There was no residual ASD shunting in 6 dogs. In 3 of the 5 dogs with postoperative residual shunting it was judged to be decreased and hemodynamically unimportant relative to the dogs' postoperative evaluations. The mean length of event-free survival in the 10 dogs that underwent successful transcatheter ASD closure was 22.2 ± 10.2 months.     

A Prospective, Randomized, Double-Blinded, Placebo-Controlled Study of Human Intravenous Immunoglobulin for the Acute Management of Presumptive Primary Immune-Mediated Thrombocytopenia in Dogs

Background: Immune-mediated thrombocytopenia (IMT) is a common hematologic disorder in dogs. Human intravenous immunoglobulin (hIVIG) may have a beneficial effect in canine IMT.
Hypothesis: A single hIVIG infusion (0.5 g/kg) in dogs with presumed primary IMT (pIMT) is a safe adjunctive emergency treatment to accelerate platelet count recovery and shorten hospitalization time without increasing the cost of patient care.
Animals: Eighteen client-owned dogs with a presumptive diagnosis of pIMT.
Methods: Prospective, randomized, double-blinded, placebo-controlled clinical trial.
Results: There were no identifiable immediate or delayed adverse reactions associated with hIVIG administration over a 6-month period. The median platelet count recovery time for the hIVIG group was 3.5 days (mean ± SD: 3.7 ± 1.3 days; range, 2–7 days) and 7.5 days (mean ± SD: 7.8 ± 3.9 days; range, 3–12 days) for the placebo group. The median duration of hospitalization for hIVIG group was 4 days (mean ± SD: 4.2 ± 0.4 days; range, 2–8 days) and 8 days (mean ± SD: 8.3 ± 0.6 days; range, 4–12 days) for the placebo group. There was no significant difference between groups with respect to expense of initial patient care, whereas significant reduction in platelet count recovery time ( P = .018) and duration of hospitalization ( P = .027) were detected in the hIVIG group.
Conclusions and Clinical Importance: Compared with corticosteroids alone, adjunctive emergency therapy of a single hIVIG infusion was safe and associated with a significant reduction in platelet count recovery time and duration of hospitalization without increasing the expense of medical care in a small group of dogs with presumed pIMT.     

The Effects of Active Peripheral Skin Warming on Perioperative Hypothermia in Dogs

Objective — This study evaluates the efficacy of three perioperative warming protocols to improve control of body temperature in anesthetized dogs.
Study Design — A randomized controlled clinical trial.
Animals or Sample Population — Thirty-two client-owned dogs.
Methods — We prospectively studied dogs entering the University of Pennsylvania Veterinary Teaching Hospital for orthopedic or dental procedures and assigned them to one of three perianes-thetic warming protocols. Group 1 (n = 10) had a single circulating warm water mattress applied over the trunk (single-trunk warming). Group 2 (n = 12) had two circulating warm water mattresses, one placed over and one under the trunk (double-trunk warming). Group 3 (n = 10) had warm circulating mattresses applied only around the feet and legs of all available limbs (peripheral warming). The warm water mattresses were prewarmed and maintained at 40°C (104°F) and applied immediately after induction of general anesthesia. All dogs had a layer of thick terry cloth toweling beneath and above the trunk. Body temperature measurements were recorded every 15 minutes for the first 2.5 hours of anesthesia.
Results — The lowest mean temperature for dogs in group 3 was 37.4 ± 0.2°C (99.5°F), compared with 36.4 ± 0.2°C (97.4°F) and 36.7 ± 0.2°C (98.0°F) in groups 1 and 2, respectively.
Conclusions — Dogs in the peripheral warming group maintained significantly higher core body temperatures than dogs in either trunk warming groups throughout the 2.5-hour study period.
Clinical Relevance — To maintain body heat in dogs during anesthesia, it is more effective to warm the feet and legs than to warm the trunk.     

Effect of Experimental Hypothyroidism on Glomerular Filtration Rate and Plasma Creatinine Concentration in Dogs

Background: Hypothyroidism affects renal function in a manner opposite the effects of hyperthyroidism.
Objective: To evaluate the effects of experimentally induced hypothyroidism on glomerular filtration rate (GFR) and basal plasma creatinine concentration in dogs.
Animals: Sixteen anestrous, female dogs.
Methods: Hypothyroidism was induced by administration of ¹³¹I in 8 dogs, and 8 healthy euthyroid dogs acted as controls. Exogenous plasma creatinine clearance (an estimate of GFR) was measured in all dogs before (control period) and 43–50 weeks after induction of hypothyroidism (posttreatment period). Other pharmacokinetic parameters of creatinine were also determined.
Results: No significant difference was observed for basal plasma creatinine concentration and creatinine clearance between control and hypothyroid dogs in the control period. In the posttreatment period, mean ± SD creatinine clearance in the hypothyroid group (2.13 ± 0.48 mL/min/kg) was lower ( P < .001) than that of the control group (3.20 ± 0.42 mL/kg/min). Nevertheless, basal plasma creatinine concentrations were not significantly different between the hypothyroid and control groups (0.74 ± 0.18 versus 0.70 ± 0.08 mg/dL, respectively) because endogenous production of creatinine was decreased in hypothyroid dogs (22 ± 3 versus 32 ± 5 mg/kg/d, P =.001).
Conclusion and Clinical Importance: Hypothyroidism causes a substantial decrease in GFR without altering plasma creatinine concentrations, indicating that GFR evaluation is needed to identify renal dysfunction in such patients.     

Intermittent gastroesophageal intussusception in a cat with idiopathic megaesophagus

An adult female domestic shorthair cat was evaluated for chronic upper respiratory disease and vomiting. A diagnosis of idiopathic megaesophagus with intermittent gastroesophageal intussusception (GEI) was made based on radiographic and endoscopic examinations. The GEI was manually reduced by use of a stomach tube during the endoscopic procedure. An incisional gastropexy was performed to prevent recurrence. Gastroesophageal intussusception is a rare condition in cats. In dogs it is usually associated with rapid progression of clinical signs, culminating in death. In this cat, the condition was associated with chronic signs, probably due to the intermittent nature of the GEI.