Elizabeth J. Barrett

Surgical technique and short-term outcome for experimental laparoscopic closure of the epiploic foramen in 6 horses.

Objective To describe a laparoscopic technique for, and short-term outcome after, closure of the epiploic foramen (EF) in horses. Study Design Descriptive, experimental study. Animals Healthy, adult horses (n = 6). Methods Laparoscopic portals to approach the EF were identified in standing horses. Under laparoscopic observation, the gastropancreatic fold and right lobe of the pancreas were grasped with Babcock forceps and secured to the caudate hepatic lobe using helical titanium coils to obliterate the EF. Surgical procedure time and intra- and postoperative complications were recorded. Serial analysis of select serum enzymes was used as an indication of involvement of the pancreas and liver. Closure was reevaluated at 4 weeks using repeat laparoscopy, and necropsy was performed immediately after. Results At initial surgery, EF closure was successful in all 6 horses; median surgical time was 40.5 minutes (range, 22–110 minutes). Serum gamma-glutamyl transferase (GGT) and sorbitol dehydrogenase (SDH) were not significantly altered by the surgical procedure; however, aspartate aminotransferase (AST) and amylase (AMY) were transiently increased. At repeat laparoscopic reevaluation, closure was complete in 5 horses, with partial closure of the EF observed in 1 horse. No complications related to the procedure were noted during or after surgery in any horse. Conclusions EF closure in the standing horse can be accomplished without complications to the surrounding organs and vessels.OBJECTIVE To describe a laparoscopic technique for, and short-term outcome after, closure of the epiploic foramen (EF) in horses. STUDY DESIGN Descriptive, experimental study. ANIMALS Healthy, adult horses (n = 6). METHODS Laparoscopic portals to approach the EF were identified in standing horses. Under laparoscopic observation, the gastropancreatic fold and right lobe of the pancreas were grasped with Babcock forceps and secured to the caudate hepatic lobe using helical titanium coils to obliterate the EF. Surgical procedure time and intra- and postoperative complications were recorded. Serial analysis of select serum enzymes was used as an indication of involvement of the pancreas and liver. Closure was reevaluated at 4 weeks using repeat laparoscopy, and necropsy was performed immediately after. RESULTS At initial surgery, EF closure was successful in all 6 horses; median surgical time was 40.5 minutes (range, 22-110 minutes). Serum gamma-glutamyl transferase (GGT) and sorbitol dehydrogenase (SDH) were not significantly altered by the surgical procedure; however, aspartate aminotransferase (AST) and amylase (AMY) were transiently increased. At repeat laparoscopic reevaluation, closure was complete in 5 horses, with partial closure of the EF observed in 1 horse. No complications related to the procedure were noted during or after surgery in any horse. CONCLUSIONS EF closure in the standing horse can be accomplished without complications to the surrounding organs and vessels.

Ultrasound assisted arthroscopic approach for removal of basilar sesamoid fragments of the proximal sesamoid bones in horses.

Objective To describe an ultrasound assisted arthroscopic approach for removal of non-articular basilar sesamoid fragments in Thoroughbred yearlings. Animals Thoroughbred yearlings (n = 7). Methods Basilar sesamoid fragments identified during pre-sale radiographic examination were removed using a palmar/plantar arthroscopic approach to the fetlock joint and ultrasonographic guidance. Complete fragment removal was confirmed by ultrasonography and radiography. Results Basilar sesamoid fracture fragments were localized and removed successfully using rongeurs and a radiofrequency probe for soft tissue dissection of the fragment. Complete fragment removal was confirmed by ultrasonography and radiography. No intra- or postoperative complications occurred. At 6–8 months follow-up, no fragments or bony proliferation at the base of the sesamoid was observed. Conclusions Ultrasonographic guidance can be used to facilitate localization, dissection, and confirmation of removal of basilar fragments of the proximal sesamoid bone.OBJECTIVE To describe an ultrasound assisted arthroscopic approach for removal of non-articular basilar sesamoid fragments in Thoroughbred yearlings. ANIMALS Thoroughbred yearlings (n = 7). METHODS Basilar sesamoid fragments identified during pre-sale radiographic examination were removed using a palmar/plantar arthroscopic approach to the fetlock joint and ultrasonographic guidance. Complete fragment removal was confirmed by ultrasonography and radiography. RESULTS Basilar sesamoid fracture fragments were localized and removed successfully using rongeurs and a radiofrequency probe for soft tissue dissection of the fragment. Complete fragment removal was confirmed by ultrasonography and radiography. No intra- or postoperative complications occurred. At 6-8 months follow-up, no fragments or bony proliferation at the base of the sesamoid was observed. CONCLUSIONS Ultrasonographic guidance can be used to facilitate localization, dissection, and confirmation of removal of basilar fragments of the proximal sesamoid bone.

Biomechanical Testing of a Novel Tendon Implant Device for the Repair of Equine Flexor Tendon Lacerations

OBJECTIVE To compare in vitro strength and failure characteristics of a tendon implant against a 3 loop pulley suture pattern for equine superficial digital flexor tendon (SDFT) laceration repair. STUDY DESIGN Experimental. STUDY POPULATION Cadaveric equine forelimb SDFT (n = 16). METHODS One tendon of each of 8 pair of SDFT was randomly selected for repair with either the 3-loop pulley (3LP) suture pattern using 2 polydioxanone or with 4 stainless steel suture and anchor implants (SA). Ultimate load to failure, mode of failure, gap at failure, and load to 2 mm gap were obtained using a materials testing system synchronized with a high-speed camera. Statistical evaluation was made using Students t-test; significance was set at P ≤ .05. RESULTS The 3LP failed at a significantly (P = .0001) greater load (363.5 ± 83.7 N) than SA (132.4 ± 26.8 N), but the load to a 2 mm gap (3LP = 164.9 ± 67.7 N, SA = 114.5 ± 21.5 N) was not significantly different (P = .09). Failure mode was by suture pull out and anchor pull out respectively. The gap at failure was significantly larger in the 3LP than in SA repair (P = .000005). CONCLUSIONS Both the SA repair and the 3LP resisted similar tension to 2 mm gap. However, the ultimate load to failure of the SA repair was only 36% that of the 3LP repair.

Effects of gastric distension on intraabdominal pressures in horses

OBJECTIVE To determine the effect of gastric distension on intraabdominal pressures (IAP) measured directly from the intraperitoneal space. DESIGN Prospective, experimental study. SETTING A university-based equine research facility. ANIMALS Ten healthy adult horses, 5 males and 5 females. INTERVENTIONS Intraabdominal pressures were measured through an intraperitoneal cannula zeroed at a height midway between the height of the tuber ishii and point of the shoulder at 6 time points: at rest, after placement of a nasogastric tube, and after instillation of each 5 L increment up to a total of 20 L of water. Simultaneously, mean arterial pressures (MAP) were obtained using a tail cuff, and abdominal perfusion pressures (APP) were calculated using the measured IAP minus the measured MAP. MEASUREMENTS AND MAIN RESULTS Baseline direct IAP measurements were subatmospheric (-4.5 ± 3.0 cm H2 O). IAPs were not significantly affected by placement of a nasogastric tube (-2.69, 95% CI [-3.24, -2.14], P = 0.4195), but were significantly increased after placement of 5 L (-1.73, 95% CI [-2.28, -1.18], P = 0.0015), 10 L (-0.54, 95% CI [-1.09,0.01], P = 0.0001), 15 L (0.89, 95% CI [0.34, 1.44], P = 0.0001), or 20 L (3.08, 95% CI [2.53, 3.63], P = 0.0001) of water into the stomach. APPs were not significantly different for any volume of fluid infused into the stomach (P = 0.05 for all comparisons). CONCLUSION IAPs were significantly increased when > 5 L of water was infused into the stomach. These results indicate the need for further research in clinical cases to determine the relationship between gastric pressures and the development of intraabdominal hypertension in horses.Objective To determine the effect of gastric distension on intraabdominal pressures (IAP) measured directly from the intraperitoneal space. Design Prospective, experimental study. Setting A university-based equine research facility. Animals Ten healthy adult horses, 5 males and 5 females. Interventions Intraabdominal pressures were measured through an intraperitoneal cannula zeroed at a height midway between the height of the tuber ishii and point of the shoulder at 6 time points: at rest, after placement of a nasogastric tube, and after instillation of each 5 L increment up to a total of 20 L of water. Simultaneously, mean arterial pressures (MAP) were obtained using a tail cuff, and abdominal perfusion pressures (APP) were calculated using the measured IAP minus the measured MAP. Measurements and Main Results Baseline direct IAP measurements were subatmospheric (–4.5 ± 3.0 cm H2O). IAPs were not significantly affected by placement of a nasogastric tube (–2.69, 95% CI [–3.24, –2.14], P = 0.4195), but were significantly increased after placement of 5 L (–1.73, 95% CI [–2.28, –1.18], P = 0.0015), 10 L (–0.54, 95% CI [–1.09,0.01], P = 0.0001), 15 L (0.89, 95% CI [0.34, 1.44], P = 0.0001), or 20 L (3.08, 95% CI [2.53, 3.63], P = 0.0001) of water into the stomach. APPs were not significantly different for any volume of fluid infused into the stomach (P = 0.05 for all comparisons). Conclusion IAPs were significantly increased when > 5 L of water was infused into the stomach. These results indicate the need for further research in clinical cases to determine the relationship between gastric pressures and the development of intraabdominal hypertension in horses.

Effects of compressive abdominal bandaging and transrectal palpation on intra-abdominal pressures in horses.

OBJECTIVE To determine the effect of an abdominal support wrap and transrectal abdominal palpation on intra-abdominal pressures (IAPs) measured directly from the peritoneal space. DESIGN Prospective, experimental study. SETTING A university-based equine research facility. ANIMALS Ten healthy adult horses, 5 males and 5 females. INTERVENTIONS IAPs were measured through an intraperitoneal cannula zeroed at a height midway between the height of the tuber ishii and point of the shoulder. Triplicate measurements were obtained at rest, during transrectal palpation, after placement of an abdominal support wrap, and during transrectal palpation with the support wrap still in place. Simultaneous mean arterial pressures were obtained using a tail cuff and abdominal perfusion pressures were calculated using the measured IAP minus the measured mean arterial pressures. MEASUREMENTS AND MAIN RESULTS Baseline direct pressure measurements were subatmospheric (-4.5 ± 3.0 cm H(2) O). IAPs were not significantly affected by transrectal palpation, but were significantly increased after placement of an abdominal support wrap (-1.19 ± 3.01 cm H(2) O; P = 0.01). Abdominal perfusion pressures were not significantly affected by either transrectal palpation or application of the support wrap. CONCLUSION IAPs were significantly increased after application of an abdominal support wrap commonly used after exploratory laparotomy. Further investigations are warranted to determine the clinical implications of abdominal bandaging on IAP and its implications on postoperative complications including intra-abdominal hypertension. However, transrectal abdominal palpation likely does not contribute to abdominal hypertension in normal horses.Objective To determine the effect of an abdominal support wrap and transrectal abdominal palpation on intra-abdominal pressures (IAPs) measured directly from the peritoneal space. Design Prospective, experimental study. Setting A university-based equine research facility. Animals Ten healthy adult horses, 5 males and 5 females. Interventions IAPs were measured through an intraperitoneal cannula zeroed at a height midway between the height of the tuber ishii and point of the shoulder. Triplicate measurements were obtained at rest, during transrectal palpation, after placement of an abdominal support wrap, and during transrectal palpation with the support wrap still in place. Simultaneous mean arterial pressures were obtained using a tail cuff and abdominal perfusion pressures were calculated using the measured IAP minus the measured mean arterial pressures. Measurements and Main Results Baseline direct pressure measurements were subatmospheric (−4.5 ± 3.0 cm H2O). IAPs were not significantly affected by transrectal palpation, but were significantly increased after placement of an abdominal support wrap (−1.19 ± 3.01 cm H2O; P = 0.01). Abdominal perfusion pressures were not significantly affected by either transrectal palpation or application of the support wrap. Conclusion IAPs were significantly increased after application of an abdominal support wrap commonly used after exploratory laparotomy. Further investigations are warranted to determine the clinical implications of abdominal bandaging on IAP and its implications on postoperative complications including intra-abdominal hypertension. However, transrectal abdominal palpation likely does not contribute to abdominal hypertension in normal horses.

Management of enterocutaneous fistula associated with an umbilical hernia in a two-year-old horse

Enterocutaneous fistula (ECF) occurs when there is open communication between the lumen of intestine and the skin. This report describes a two-year-old, American Quarter Horse filly presented with an acute ECF involving the ileum entrapped within an umbilical hernia. After four days of conservative therapy and worsening of hydration status and electrolyte and acid-base imbalances, surgical correction of the ECF was performed. The filly was stable 24 hours after surgery and eventually made a full recovery.

Ex-Vivo Evaluation of a Modified Teno Fix® Device Repair Pattern Versus a 3-Loop Pulley for Repair of Equine Flexor Tendons

OBJECTIVE To compare the load to ultimate failure, load to a 2 mm gap, mode of failure, and gap at failure (mm) of the Teno Fix(®) (TF) to the 3-loop pulley (3LP) for repair of equine tendon lacerations. The use of 4TF devices versus 5TF devices on load to ultimate failure and load to a 2 mm gap was also compared. STUDY DESIGN Ex vivo biomechanical study; unbalanced incomplete block (horse) design. SAMPLES Cadaveric equine forelimb superficial digital flexor tendon (n = 20 paired tendons). METHODS Ten tendon pairs were selected randomly and repaired with a 3LP and 4TF pattern, and 10 tendon pairs repaired with a 3LP and 5TF pattern. Load to ultimate failure, load to a 2 mm gap, mode of failure, and gap at failure were obtained using materials testing. RESULTS The 3LP had a significantly greater ultimate load to failure (P < .001, respectively) and a significantly higher load to a 2 mm gap than both TF repairs (P < .001, respectively). The most frequent mode of failure was suture pull-out for the 3LP and anchor pull-out for the TF. Gap at failure was significantly larger in the 3LP than both TF repairs (P < .001). The ultimate load to failure was significantly higher for the 5TF than the 4TF (P = .004) but there was no significant difference in load to a 2 mm gap, or gap at failure between both TF repairs (P = .11, P = .15, respectively). CONCLUSIONS Neither TF repair was stronger than the 3LP in load to ultimate failure and load to a 2 mm gap. Addition of a fifth TF device significantly increased the load to ultimate failure but did effect the load to a 2 mm gap over the 4TF.

Ultrasound Assisted Arthroscopic Approach for Removal of Basilar Sesamoid Fragments of the Proximal Sesamoid Bones in Horses: Ultrasound Assisted Sesamoid Fragment Removal

Objective To describe an ultrasound assisted arthroscopic approach for removal of non-articular basilar sesamoid fragments in Thoroughbred yearlings. Animals Thoroughbred yearlings (n = 7). Methods Basilar sesamoid fragments identified during pre-sale radiographic examination were removed using a palmar/plantar arthroscopic approach to the fetlock joint and ultrasonographic guidance. Complete fragment removal was confirmed by ultrasonography and radiography. Results Basilar sesamoid fracture fragments were localized and removed successfully using rongeurs and a radiofrequency probe for soft tissue dissection of the fragment. Complete fragment removal was confirmed by ultrasonography and radiography. No intra- or postoperative complications occurred. At 6–8 months follow-up, no fragments or bony proliferation at the base of the sesamoid was observed. Conclusions Ultrasonographic guidance can be used to facilitate localization, dissection, and confirmation of removal of basilar fragments of the proximal sesamoid bone.OBJECTIVE To describe an ultrasound assisted arthroscopic approach for removal of non-articular basilar sesamoid fragments in Thoroughbred yearlings. ANIMALS Thoroughbred yearlings (n = 7). METHODS Basilar sesamoid fragments identified during pre-sale radiographic examination were removed using a palmar/plantar arthroscopic approach to the fetlock joint and ultrasonographic guidance. Complete fragment removal was confirmed by ultrasonography and radiography. RESULTS Basilar sesamoid fracture fragments were localized and removed successfully using rongeurs and a radiofrequency probe for soft tissue dissection of the fragment. Complete fragment removal was confirmed by ultrasonography and radiography. No intra- or postoperative complications occurred. At 6-8 months follow-up, no fragments or bony proliferation at the base of the sesamoid was observed. CONCLUSIONS Ultrasonographic guidance can be used to facilitate localization, dissection, and confirmation of removal of basilar fragments of the proximal sesamoid bone.