Feasibility of open-chest cardiopulmonary resuscitation through a transdiaphragmatic approach in dogs.

OBJECTIVE: To describe and evaluate the feasibility of a transdiaphragmatic (TD) approach for open-chest cardiopulmonary resuscitation (OCCPR) as an alternative to a traditional lateral thoracotomy (LT) in a canine cadaver model. STUDY DESIGN: Randomized noninferiority ex vivo study. ANIMALS: Fourteen canine cadavers weighing 17.4-30.2 kg. METHODS: An LT and a TD approach to the heart were performed in each cadaver. The order of procedures as well as an assignment to specific operators were randomized before starting the study. Data recorded included the time between incision and initiation of cardiac compressions; time between initiation of the first suture placement and closure of the intrapleural space; time between initiation of the first suture placement and final skin suture; trauma to pulmonary, cardiac, hepatic and neurovascular structures; distance between the caval foramen and diaphragmatic incision; the intercostal space entered during LT; and appropriate closure. RESULTS: The mean time between incision and initiation of cardiac compressions for the TD approach (85 ± 35 seconds) was noninferior to the LT (84 ± 28 seconds). The pleural space was closed faster after the TD approach (531 ± 276 seconds) than after the lateral approach (817 ± 294 seconds, P = .03). Total duration of closure did not differ between techniques (P = .11). There was no difference between the complication rates of each approach. CONCLUSION: The TD approach did not prolong the procedure or increase the complication rate compared with an LT. CLINICAL SIGNIFICANCE: This study provides evidence to support additional investigation of the TD approach for OCCPR to determine its efficacy and safety in live animals.

Computer-Assisted Surgery Using 3D Printed Saw Guides for Acute Correction of Antebrachial Angular Limb Deformities in Dogs.

OBJECTIVE: The aim of this study was to report the use of custom saw guides produced using computed tomographic imaging (CT), computer simulation and three-dimensional (3D) printing to aid surgical correction of antebrachial deformities in six dogs. MATERIALS AND METHODS: Antebrachial limb deformities in four small, and two large, breed dogs (seven limbs) were surgically corrected by a radial closing wedge ostectomy and ulnar osteotomy. The location and orientation of the wedge ostectomy were determined using CT data, computer-assisted planning and production of a saw guide in plastic using a 3D printer. At surgery, the guide was clamped to the surface of the radius and used to direct the oscillating saw blade. The resultant ostectomy was closed and stabilized with a bone plate. RESULTS: Five limbs healed without complications. One limb was re-operated due to a poorly resolved rotational component of the deformity. One limb required additional stabilisation with external fixation due to screw loosening. The owners of five dogs completed a Canine Orthopedic Index survey at a follow-up period of 37 to 81 months. The median preoperative score was 3.5 and the median postoperative score was 1, representing an overall positive effect of surgery. Radiographically, 5/7 limbs were corrected in the frontal plane (2/7 were under-corrected). Similarly, 5/7 limbs were corrected in the sagittal plane, and 2/7 were over-corrected in the sagittal place. CONCLUSIONS: Computer-aided design and rapid prototyping technologies can be used to create saw guides to simplify one-stage corrective osteotomies of the antebrachium using internal fixation in dogs. Despite the encouraging results, accurate correction of rotational deformity was problematic and this aspect requires further development.

Clinical outcomes of patient-specific porous titanium endoprostheses in dogs with tumors of the mandible, radius, or tibia: 12 cases (2013-2016).

OBJECTIVE To characterize the processes involved in and outcomes achieved with custom-designed patient-specific implants to provide functional replacement of skeletal structures in dogs with tumors of the mandible, radius, or tibia. DESIGN Prospective case series. ANIMALS 6 dogs with mandibular tumors, 5 with tumors of the distal aspect of the radius, and 1 with a tumor in the distal aspect of the tibia treated from June 2013 to September 2016 at 3 referral centers. PROCEDURES After tumor staging, implants were designed from patients' CT scans by means of various computer-aided design applications and printed by means of selective laser melting in titanium-6 aluminum-4 vanadium alloy. A cutting jig was created in thermoplastic to ensure each osteotomy was performed as planned. Following ostectomy, the implant was secured into the defect with screws of appropriate size and length. RESULTS Initial return to normal clinical function was good to excellent for 11 of the 12 dogs. However, major complications resulted in revision of the implant or amputation of the limb in 5 dogs, and at least 3 of these complications were considered a consequence of faulty implant design or manufacturing. Infection developed in 2 dogs and was successfully treated in 1 dog. The longest-surviving dog maintained good limb function for 2 years. CONCLUSIONS AND CLINICAL RELEVANCE This is the largest reported series of dogs managed with customized 3-D-printed titanium implants. The 3-D printing allowed complex and patient-specific 3-D geometries to be fabricated, enabling function-sparing treatment of bone cancer affecting multiple anatomic sites.