Objective—To compare the amount of air leakage into the thoracic cavity associated with each of 4 thoracostomy tube placement techniques in canine cadavers.
Sample Population—28 canine cadavers.
Procedures—Thoracostomy tube placement techniques (7 cadavers/technique) included subcutaneous tunneling with a silicone tube by use of Carmalt forceps or with a polyvinyl chloride tube by use of a trocar (SC-CARM and SC-TRO, respectively) and tunneling under the latissimus dorsi muscle with similar tube-instrument techniques (LD-CARM and LD-TRO, respectively). Differences in intrapleural pressures (IPPs) measured before and after tube placement and before and after tube removal were calculated; duration of air leakage around the tubes was assessed by use of a 3-chamber thoracic drainage system.
Results—Tunneling method and depth had no interaction effect on the difference in IPP measured before and after tube placement; the IPP difference for both forceps technique groups was significantly greater than findings for both trocar technique groups. Tunneling method and depth had an interaction effect on the difference in IPP measured before and after tube removal; compared with SC-TRO and LD-CARM group differences, the SC-CARM group difference was significantly greater, but the LD-TRO group difference was similar. More intermittent air leakage was associated with the 2 forceps techniques than with the 2 trocar techniques.
Conclusions and Clinical Relevance—Trocar-implemented thoracostomy tube placement in canine cadavers resulted in less air leakage than the forceps method. Air leakage upon tube removal was less pronounced for the LD-CARM technique than the SC-CARM technique. The LD-TRO technique is recommended to prevent iatrogenic pneumothorax in dogs.
Objective—To evaluate the effects of fascial abrasion, fasciotomy, and fascial excision on cutaneous wound healing in cats.
Animals—Eight 1- to 3-year-old domestic shorthair cats.
Procedures—8 evenly spaced 4-cm2 skin wounds were created on each cat's dorsum, and the underlying subcutaneous tissue was removed to expose the epaxial muscle fascia. Wounds were randomized to receive 1 of 4 treatments (2 wounds/treatment/cat): fascial abrasion, fasciotomy, fascial excision, or control treatment (muscle fascia not disturbed). Bandages were changed and digital photographs and acetate tracings of the wounds were obtained for planimetry daily for 1 week, every other day for 2 weeks, and then every third day for 3 weeks (ie, 40-day observation period). Digitized images were evaluated for granulation tissue formation, wound contraction (surface area measurements), and area of epithelialization.
Results—The epithelialized area and open and total wound areas did not differ among treatments at any time point. Time to the first appearance of granulation tissue was significantly shorter for all treatment groups, compared with that of the control group. Time to achieve granulation tissue coverage of wound base was significantly shorter following fasciotomy (9.6 days) and fascial excision (9.0 days), compared with that of control treatment (18.5 days) or abrasion (16.7 days). Numbers of wounds that developed exuberant granulation tissue following fascial excision (9/16) and control treatment (3/16) differed significantly.
Conclusions and Clinical Relevance—Fasciotomy and fascial excision facilitated early granulation tissue development in cutaneous wounds in cats. In clinical use, these fascial treatments may expedite secondary wound closure or skin grafting.
Objective—To evaluate the analgesic properties of transdermally administered fentanyl and IM administered buprenorphine in sheep undergoing unilateral tibial osteotomy.
Animals—20 mature sheep.
Procedures—Fentanyl patches (n = 15 sheep) or placebo patches (5 sheep) were applied 12 hours before sheep underwent general anesthesia and a unilateral tibial osteotomy. Buprenorphine was administered to the placebo group every 6 hours commencing at time of induction. Signs of pain were assessed every 12 hours after surgery by 2 independent observers unaware of treatment groups.
Results—There were no differences in preoperative and intraoperative physiologic data between the 2 groups. Sheep treated with fentanyl required less preoperative administration of diazepam for sedation and had significantly lower postoperative pain scores, compared with those treated with buprenorphine. No complications associated with the antebrachium at the site of patch application were detected.
Conclusions and Clinical Relevance—Under the conditions of this study, transdermally administered fentanyl was a superior option to IM administered buprenorphine for alleviation of postoperative orthopedic pain in sheep. This information can be used to assist clinicians in the development of a rational analgesic regimen for research and clinical patients.
Objective—To establish reference intervals for cytologic and biochemical variables in peritoneal fluid, whole blood, and plasma in calves with congenital umbilical hernias (CUHs) before and after herniorrhaphy and to assess whether those variables in calves with CUHs were altered, compared with findings in clinically normal calves.
Animals—20 Holstein calves with or without a CUH.
Procedures—10 calves with CUHs underwent herniorrhaphy. Blood and peritoneal fluid samples from all 20 calves were collected for cytologic and biochemical analyses on days 0 (before surgery), 1, 3, 5, 7, and 15. Data from the 2 groups were compared.
Results—Reference intervals for the variables of interest were established for each group. Before surgery, calves with CUHs had significantly greater plasma total protein concentration and creatine kinase (CK) and aspartate aminotransferase activities and peritoneal fluid specific gravity values, compared with values for calves without CUHs. At various time points after surgery, peritoneal fluid total protein concentration; fibrinogen concentration; nucleated cell, polymorphonuclear cell, and lymphocyte counts; specific gravity; and lactate dehydrogenase, aspartate aminotransferase, and CK activities in calves with CUHs were significantly different from values in calves without CUHs. Some plasma and blood variables (eg, total protein concentration, neutrophil count, and CK activity) were significantly different between the 2 groups.
Conclusions and Clinical Relevance—Values of certain cytologic and biochemical variables in peritoneal fluid, blood, and plasma were different between calves with and without CUHs. Thus, determination of reference intervals for these variables is important for interpreting diagnostic test results in calves with CUHs.
Objective—To evaluate the effect of platelet-rich plasma on wounds on the distal aspect of the forelimb in horses.
Animals—6 mixed-breed 10- to 15-year-old mares.
Procedures—3 wounds were created on metacarpal regions in each of 6 horses (n = 36 wounds total). Eighteen wounds were treated with platelet-rich plasma and bandaged, whereas 18 control wounds were similarly bandaged with no prior topical treatment. Decrease in wound surface area and the required number of excisions of exuberant granulation tissue were recorded until complete healing. Tissue specimens were taken from wounds at 1 week for histologic examination and measurement of transforming growth factor-β1 concentrations and at closure for histologic examination, biomechanical evaluation, and measurement of collagen type I and type III mRNA.
Results—Platelet-rich plasma favored excessive development of granulation tissue and significantly slowed wound healing at 1, 2, and 3 weeks after surgery. Transforming growth factor-β1 had a 1.6-fold higher concentration in treated wounds, compared with untreated wounds. Histologic, biomechanical, and gene expression data did not differ significantly between treated and control wounds.
Conclusions and Clinical Relevance—Topical application of autologous platelet-rich plasma did not accelerate or improve the quality of repair of small granulating wounds on limbs of horses. This treatment may better suit wounds with massive tissue loss or, alternatively, chronic wounds that would benefit from a fresh source of mediators to accelerate the healing process.
Objective—To assess the in vitro performance of suction drains.
Sample Population—11 drainage systems (3 rigid drains and 8 compressible drains [2 grenade type, 5 concertina type, and 1 pancake type]).
Procedures—A pressure transducer was connected to the patient end of each drainage system. Serial pressure measurements were obtained during incremental addition and removal of air into the reservoir of each system, followed by incremental addition of water. The volume of air removed to restore the initial suction was recorded. Maximum filling volume was compared with the stated reservoir volume. For compressible drains, the suction generated following 3 compression methods was compared.
Results—The initial suction generated by the drainage systems ranged from −633.4 ± 14.7 mm Hg to −90.1 ± 19.5 mm Hg. Rigid drains had greater initial suction than compressible drains. For all compressible drains, compression with 2 hands, rather than 1, produced greater suction, apart from the pancake-type (200-mL reservoir) drains for which the reverse occurred. For grenade-type drains, rolling the reservoir from apex to base generated greater suction than 1-hand compression. Maximum filling volume was lower than stated for the concertina-type drains with 50-mL, 25-mL, and 400-mL reservoirs and the rigid-type drain with a 200-mL reservoir. As increments of air or water were added, compressible drains lost suction rapidly up to a fill of 20% to 30% and then more gradually. Rigid drains lost suction more slowly.
Conclusions and Clinical Relevance—Drainage systems varied widely in their initial suction and rate of loss of suction during filling.
Objective—To evaluate and quantify in vitro dimensional changes of ameroid ring constrictors (ARCs) with and without the outer stainless steel ring in place over time.
Sample Population—12 ARCs (5.0-mm diameter).
Procedures—6 ARCs were immersed in canine plasma baths for 34 days without the stainless steel outer ring in place (group N), and 6 ARCs were immersed in canine plasma baths with the stainless steel outer ring in place (group R). The ARCs were digitally imaged at day 0, daily for the first 10 days, then on days 14, 20, 27, and 34. Inner diameter, outer diameter, luminal area, and height were measured for each time point. Volume and weight of rings were obtained at the start and completion of the study.
Results—The inner diameter, outer diameter, and luminal area were significantly different between the 2 groups over the course of 34 days. The inner diameter and luminal area of the R-group constructs did not change significantly, while the inner diameter, outer diameter, luminal area, and height of N-group constructs all significantly increased over the course of the study.
Conclusions and Clinical Relevance—R-group constructs had insignificant centripetal swelling without ring closure, whereas N-group constructs had significant generalized centrifugal expansion. Results of this study indicated that the outer stainless steel ring of an ARC may not be necessary for attenuation and closure of some single extrahepatic portosystemic shunts.
Objective—To determine the macroscopic effects of topical application of taurolidine on second intention healing of experimentally induced wounds in rats.
Animals—32 adult Sprague-Dawley female rats.
Procedures—In each rat, 2 skin wounds were created in the lumbar area. Groups of 7 rats were assigned to have 1 wound treated topically with hydroxycellulose gel (HDCG), 2% taurolidine in HDCG (T-HDCG), 2% taurolidine–sodium citrate solution, or bacitracin-neomycin-polymyxin B ointment; the other wound was not treated. Four control rats (8 untreated wounds) were used. Wounds were monitored for contraction, epithelialization, and complete healing at 4, 8, and 14 days after wound creation. The number of days to complete healing was also recorded for each wound.
Results—Compared with other treatments or untreated wounds, wounds treated with T-HDCG had decreased total healing at day 8 and decreased epithelialization and decreased total healing at day 14. Wounds treated with T-HDCG required approximately 3 days longer to completely heal than all other treated and untreated wounds. Application of bacitracinneomycin-polymyxin B ointment did not enhance wound healing. Mean time to complete healing of untreated wounds in all treatment and control groups was 10.00 to 10.14 days.
Conclusions and Clinical Relevance—In rats, topical application of T-HDCG to wounds had a negative effect on second intention healing by delaying the epithelialization process. In mammals, generally, wounds treated topically with taurolidine may need to be treated and monitored for a longer period than other wounds treated with other common woundhealing compounds or untreated wounds.
Objective—To design and manufacture custom titanium bone plates and a custom cutting and drill guide by use of free-form fabrication methods and to compare variables and mechanical properties of 2 canine tibial plateau leveling methods with each other and with historical control values.
Sample Population—10 canine tibial replicas created by rapid prototyping methods.
Procedures—Application time, accuracy of correction of the tibial plateau slope (TPS), presence and magnitude of rotational and angular deformation, and replica axial stiffness for 2 chevron wedge osteotomy (CWO) methods were assessed. One involved use of freehand CWO (FHCWO) and screw hole drilling, whereas the other used jig-guided CWO (JGCWO) and screw hole drilling.
Results—Replicas used for FHCWO and JGCWO methods had similar stiffness. Although JGCWO and FHCWO did not weaken the replicas, mean axial stiffness of replicas after JGCWO was higher than after FHCWO. The JGCWO method was faster than the FHCWO method. Mean ± SD TPS after osteotomy was lower for FHCWO (4.4 ± 1.1°) than for JGCWO (9.5 ± 0.4°), and JGCWO was more accurate (target TPS, 8.9°). Slight varus was evident after FHCWO but not after JGCWO. Mean postoperative rotation after JGCWO and FHCWO did not differ from the target value or between methods.
Conclusions and Clinical Relevance—The JGCWO method was more accurate and more rapid and resulted in more stability than the FHCWO method. Use of custom drill guides could enhance the speed, accuracy, and stability of corrective osteotomies in dogs.
Objective—To evaluate the use of endoscopy in conjunction with a gastropexy technique in dogs as a potential means to aid prevention of gastric dilatation-volvulus.
Animals—12 healthy adult medium- and large-breed dogs.
Procedures—12 adult research dogs that had no abnormal physical examination findings each underwent an endoscopically assisted gastropexy procedure. On completion of the procedure, the dogs were euthanized and exploratory laparotomies were performed to evaluate the surgical site. Data recorded included anatomic location of the gastropexy, gastropexy length, and duration of procedure as well as any complications.
Results—Mean ± SD gastropexy length was 3.3 ± 0.25 cm, and mean duration of surgery was 18 ± 7 minutes. In each dog, the stomach was located in its normal anatomic position and all gastropexies were sutured to the abdominal wall at the level of the pyloric antrum. The only complications during the procedure were needle bending and breakage at the time of stay suture placement.
Conclusions and Clinical Relevance—On the basis of these findings, it appears that endoscopically assisted gastropexy is a simple, fast, safe, and reliable method of performing a prophylactic gastropexy in dogs when undertaken by a person who is skilled in endoscopy. Such a procedure maximizes the benefits of decreased morbidity and shorter duration of anesthesia associated with minimally invasive surgery. Further clinical studies are warranted to evaluate the long-term efficacy of this procedure in dogs at risk for development of gastric dilatation-volvulus.