Three-dimensional printed guides for screw placement in equine navicular bones.

OBJECTIVE: To determine the influence of a custom 3D-printed guide for placement of cortical bone screws in the equine navicular bone. STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Eight pairs of normal adult equine forelimbs. METHODS: A 3.5 × 55 mm cortical screw was placed in the longitudinal axis of each intact navicular bone. Screws were placed with a 3D-printed guide (3D) in one bone and with a traditional aiming device (AD) in the contralateral bone within each pair. Duration of surgery and the number of fluoroscopy images were compared between techniques. Screw placement was subjectively evaluated by gross examination and scored by three boarded veterinary surgeons. RESULTS: The use of a 3D-printed guide reduced the duration of surgery by 6.6 min (±1.5 min) compared to traditional screw placement (20.7 min ± 4.8 min, p < .01). Fewer peri-operative fluoroscopic images were obtained when the 3D guide was used (18 images ± 2.6 images vs. 40 images ± 5.1, p < .01). No difference was detected in navicular screw placement. CONCLUSION: The use of a 3D guide decreased the time required to place screws and the number of intraoperative images taken without affecting screw placement in intact navicular bones. CLINICAL RELEVANCE: 3D-printed guides can aid in the study, practice, and execution of surgical procedures reducing surgical time and radiation exposure throughout the operative period achieving similar results to those obtained with a conventional approach.

A survey of work-related musculoskeletal disorders associated with performing laparoscopic veterinary surgery.

OBJECTIVE: To assess the prevalence of work-related musculoskeletal disorders (WRMD) associated with laparoscopy in veterinary surgery. STUDY DESIGN: Cross-sectional survey. SAMPLE POPULATION: Veterinary surgeons who perform laparoscopy. METHODS: Responses were collected with data regarding laparoscopic activities and experience as well as whether the respondents experienced pain as a result of laparoscopy and, if so, additional information on this topic. Variables associated with the risk of experiencing pain were determined by using χ2 tests and odds ratios (OR). RESULTS: There were 149 respondents, an estimated 6% response proportion. Forty percent experienced pain that they attributed to the use of laparoscopic instruments during or after laparoscopic surgery. Surgeons who perform laparoscopic surgery frequently (at least monthly) were more likely to experience pain as a result of laparoscopic surgery compared with those who perform laparoscopic surgery infrequently (OR 2.25; 95% confidence interval 1.07-4.75; P = .033). Pain during or after laparoscopic surgery was most often experienced in the neck (81%), back (77%), and shoulders (75%), with 90% of respondents reporting that surgery exacerbated their pain. Fifty-four percent of respondents experienced the pain at home, 64% had taken painkillers for the pain, and 46% had sought other treatment for the pain such as physiotherapy, chiropractic treatment, or seeing a doctor. CONCLUSION: Laparoscopic surgery was a potential source of pain in a proportion of surgeons. Surgeons who frequently perform laparoscopic surgery were more likely to experience a WRMD. CLINICAL SIGNIFICANCE: Work-related musculoskeletal disorders may occur as a result of performing laparoscopic surgery.

Hydrogen peroxide plasma sterilization of a waterproof, high-definition video camera case for intraoperative imaging in veterinary surgery.

OBJECTIVE: To evaluate the safety and usability of a wearable, waterproof high-definition camera/case for acquisition of surgical images by sterile personnel. STUDY DESIGN: An in vitro study to test the efficacy of biodecontamination of camera cases. Usability for intraoperative image acquisition was assessed in clinical procedures. METHODS: Two waterproof GoPro Hero4 Silver camera cases were inoculated by immersion in media containing Staphylococcus pseudointermedius or Escherichia coli at ≥5.50E+07 colony forming units/mL. Cases were biodecontaminated by manual washing and hydrogen peroxide plasma sterilization. Cultures were obtained by swab and by immersion in enrichment broth before and after each contamination/decontamination cycle (n = 4). The cameras were then applied by a surgeon in clinical procedures by using either a headband or handheld mode and were assessed for usability according to 5 user characteristics. RESULTS: Cultures of all poststerilization swabs were negative. One of 8 cultures was positive in enrichment broth, consistent with a low level of contamination in 1 sample. Usability of the camera was considered poor in headband mode, with limited battery life, inability to control camera functions, and lack of zoom function affecting image quality. Handheld operation of the camera by the primary surgeon improved usability, allowing close-up still and video intraoperative image acquisition. CONCLUSION: Vaporized hydrogen peroxide sterilization of this camera case was considered effective for biodecontamination. Handheld operation improved usability for intraoperative image acquisition. CLINICAL SIGNIFICANCE: Vaporized hydrogen peroxide sterilization and thorough manual washing of a waterproof camera may provide cost effective intraoperative image acquisition for documentation purposes.

Comparison of design features and mechanical properties of commercially available Veress needles.

OBJECTIVE: To compare design features and mechanical properties of 13 commercially available Veress needles (VN). STUDY DESIGN: In vitro biomechanical study. SAMPLE POPULATION: Veress needles from 9 manufacturers (6 reusable, 6 disposable, and 1 with a reusable stylet combined with a disposable cannula) were included in the study. METHODS: Veress needles are designed with a spring-loaded stylet to protect the tip of the cannula following insertion into the abdomen. Stylet forces were measured with a scale in a test jig by moving the stylet in 0.5 mm steps into the hollow cannula. Forces and spring rates were derived from force-displacement plots. Mass, mechanical dimensions, and the bevel angle and geometry were assessed. Differences between VN models were analyzed with a univariate analysis of variance. Results are reported as mean ± SD or median (range). RESULTS: Physical and mechanical parameters differed between models. The exposed stylet length was 3.5 mm (2-7). Three bevel geometries (bias, lancet type, and back-cut) with angles between 20° and 40° were identified. Reusable VN weigh more (24.9 ± 2.2 g) than disposable designs (6.0 ± 2.3 g). The mean values for the spring rate and the residual stylet force were 0.23 ± 0.08 Nmm-1 and 0.94 ± 0.28 N, respectively. The mean force required to move the stylet to the cannula tip was 1.81 ± 0.29 N and 2.77 ± 0.54 N to move to the proximal end of the bevel. CONCLUSION: Commercially available VN use diverse bevel geometries and have different mechanical characteristics. Studies investigating laparoscopic entry complications should explicitly report the type of VN model used.

INTRAOPERATIVE IMAGE NAVIGATION: EXPERIMENTAL STUDY OF THE FEASIBILITY AND SURGEON PREFERENCE BETWEEN A STERILE ENCASED NINTENDO WIITM REMOTE AND STANDARD WIRELESS COMPUTER MOUSE.

Diagnostic imaging plays an important role in the operating room, providing surgeons with a reference and surgical plan. Surgeon autonomy in the operating room has been suggested to decrease errors that stem from communication mistakes. A standard computer mouse was compared to a wireless remote-control style controller for computer game consoles (Wiimote) for the navigation of diagnostic imaging studies by sterile personnel in this prospective survey study. Participants were recruited from a cohort of residents and faculty that use the surgical suites at our institution. Outcome assessments were based on survey data completed by study participants following each use of either the mouse or Wiimote, and compared using an analysis of variance. The mouse was significantly preferred by the study participants in the categories of handling, accuracy and efficiency, and overall satisfaction (P <0.05). The mouse was preferred to both the Wiimote and to no device, when participants were asked to rank options for image navigation. This indicates the need for the implementation of intraoperative image navigation devices, to increase surgeon autonomy in the operating room.

Frequency of Undetected Glove Perforation and Associated Risk Factors in Equine Surgery.

OBJECTIVE: To estimate the frequency of undetected perforations in surgical gloves during equine surgery and to identify risk factors associated with occurrence. STUDY DESIGN: Observational cohort study. SAMPLE POPULATION: Surgical gloves-292 pairs. METHODS: Water leak tests were performed on gloves after equine surgery to detect perforations. Fifty pairs of unused gloves were also tested. Potential risk factors were recorded. Logistic regression was used to explore associations between putative risk factors and perforation. RESULTS: No perforations were detected in the unused gloves. Of 292 pairs of used gloves tested, 80 (27%) had at least one glove perforation per pair. The frequency of perforations was not different between surgery diplomates and residents (P=.69). The length and type of surgery were significantly associated with the likelihood of undetected glove perforation with surgeries longer than 60 minutes approximately 2.5 times more likely to result in glove perforation (P=.005). Surgery classified as soft tissue, orthopedic or exploratory celiotomy was 3 times more likely to result in glove perforation than minimally invasive surgery. The perforations occurred significantly more frequently in the nondominant hand (19%) than the dominant hand (11%) (P=.009). CONCLUSION: There is a high occurrence of undetected glove perforation in equine surgery. Precautions can be suggested based on this study although further investigation is required to assess whether glove perforations are associated with surgical site infections.

Knot security and tensile strength of suture materials.

OBJECTIVE: To evaluate knot security and tensile failure load of suture tied in simple interrupted, beginning continuous, and ending continuous patterns for 11 suture materials commonly used in small animal surgery. STUDY DESIGN: Mechanical study. METHODS: For each of 11 suture material types, and 5 knot sizes (2, 3, 4, 5, and 6 throws) 2 surgeons each tied 6 knots (n = 12 for each knot size in 11 suture materials). Three types of patterns were evaluated: a simple interrupted square knot, a square knot beginning a simple continuous pattern, and the knot ending a simple continuous pattern. All knots were incubated in healthy canine donor plasma at 40°C for a minimum of 24 hours. Sutures were evaluated for knot security (knots untied, suture failed by breaking, suture slipped from the clamps, or suture untied before testing) and maximum load carried before knot slippage or knot failure (termed tensile failure load). RESULTS: Significant differences were found in knot security and tensile failure load among suture types. There was no significant difference between the simple interrupted knots and the knots at the beginning of a simple continuous pattern; however, both were significantly less likely to fail than the knots tied at the end of a simple continuous pattern. The number of throws per knot had a significant effect for knot security and tensile failure load. Surgeon experience had a significant effect on failure mode and tensile failure load. CONCLUSIONS: Suture type, number of throws per knot (knot size), suture pattern, and surgeon experience play an important role in knot security and should be considered when performing surgery.

Comparison of 3 methods of onychectomy.

The frequency of claw regrowth, bony remnants, and complications in cats that underwent forelimb onychectomy using laser, scalpel, or guillotine techniques were evaluated. Eighty-seven client-owned cats were recruited from 27 veterinary clinics in the Canadian Atlantic provinces. At least 1 year after onychectomy the cats underwent a physical examination, gait analysis, and radiographic evaluation by 1 of 2 authors. There was no significant difference in the frequency of claw regrowth among the 3 methods (P = 0.283). Significantly more cats had bony remnants following guillotine onychectomy (P < 0.001). Bony remnants were significantly associated with claw regrowth (P = 0.001). Cats that underwent laser onychectomy had significantly less post-operative complications (P = 0.023). The long-term outcome was not significantly different among the 3 methods. We conclude that leaving remnants of the third phalanx in situ is associated with an increased frequency of claw regrowth. Laser onychectomy may be preferred to reduce the risk of post-operative complications, bony remnants, and claw regrowth.

Comparaison de 3 méthodes d'onychectomie. La fréquence de la repousse des griffes, des reliquats osseux et des complications chez les chats qui avaient subi une onychectomie des pattes avant en utilisant le laser, le scalpel, ou les techniques de guillotine a été évaluée. Quatre-vingt-sept chats appartenant à des clients ont été recrutés dans 27 cliniques vétérinaires des provinces de l'Atlantique du Canada. Au moins 1 an après l'onychectomie, les chats ont subi une évaluation physique, une analyse de la démarche et une évaluation radiographique par 1 des 2 auteurs. Il n'y avait pas de différence significative dans la fréquence de la repousse des griffes entre les 3 méthodes (P = 0,283). Un nombre significativement supérieur de chats avaient des reliquats osseux après l'onychectomie à la guillotine (P < 0,001). Les reliquats osseux étaient significativement associés à la repousse de griffes (P = 0,001). Les chats qui ont subi une onychectomie au laser présentaient un nombre significativement inférieur de complications postopératoires (P = 0,023). Les résultats à long terme n'étaient pas significativement différents entre les 3 méthodes. Nous avons conclu que la présence de reliquats in situ dans la troisième phalange est associée à une fréquence accrue de repousse des griffes. L'onychectomie au laser peut être préférable pour réduire le risque de complications postopératoires, des reliquats et de la repousse des griffes.(Traduit par Isabelle Vallières).

Augmenting Veterinary Minimally Invasive Surgery: Evidence-based Review of Foundational and Novel Devices and Technology.

Veterinary minimally invasive surgery continues to grow as a specialty. With increasing experience in this field, comes improved accessibility as well as progressive complexity of procedures performed. Advancement in technology has been both a response to the growth and a necessary driver of continued refinement of this field. Innovative research leading to advancements in surgical equipment has led to the development of novel image acquisition platforms, cannulas, smoke evacuation systems, antifog devices, instrumentation, and ligating/hemostatic devices. These innovations will be reviewed and potential clinical applications are discussed.

Looking to the Future; Veterinary Robotic Surgery.

This article details the rise of surgical robots in the human surgical sphere as well as their use in veterinary medicine. Sections will describe in detail the equipment required for these procedures and the advantages and disadvantages of their use. Specific attention is given to the articulated instrumentation, which affords psychomotor benefits not only for surgical precision but also for surgeon ergonomics. A discussion of the possible indications and current use of robotics in veterinary medicine and the challenges to integrating robotics is also provided.

Evaluation of bacterial contamination on surgical drapes following use of the Bair Hugger(®) forced air warming system.

This pilot study determined the rate of bacterial contamination on surgical drapes of small animal patients warmed intra-operatively with the Bair Hugger(®) forced air warming system compared to a control method. Surgical drapes of 100 patients undergoing clean surgical procedures were swabbed with aerobic culturettes at the beginning and end of surgery. Samples were cultured on Trypticase soy agar. Contamination of the surgical drapes was identified in 6/98 cases (6.1%). There was no significant difference in the number of contaminated surgical drapes between the Bair Hugger(®) and control groups (P = 0.47).

Évaluation de la contamination bactérienne des champs opératoires après l'utilisation du système de chauffage à air pulsé Bair HuggerMD . Cette étude pilote a déterminé le taux de contamination bactérienne des champs opératoires de patients petits animaux réchauffés lors du processus peropératoire à l'aide du système de chauffage à air pulsé Bair HuggerMD comparativement à une méthode témoin. Les champs opératoires de 100 patients subissant des interventions chirurgicales propres ont été écouvillonnés avec des Culturettes aérobies au début et à la fin de la chirurgie. Les échantillons ont été cultivés sur gélose Trypticase soja. La contamination des champs opératoires a été identifiée dans 6/98 cas (6,1 %). Il n'y avait aucune différence significative dans le nombre de champs opératoires contaminés entre le groupe Bair HuggerMD et le groupe témoin (P = 0,47).(Traduit par Isabelle Vallières).

Intraoperative contamination of the suction tip in clean orthopedic surgeries in dogs and cats.

OBJECTIVE: To (1) determine suction tip (intermittent and continuous mode) contamination rate in orthopedic surgery in dogs and cats; (2) examine the effect of surgical time on contamination; and (3) report bacteria isolated. STUDY DESIGN: Clinical study. SAMPLE POPULATION: Clean orthopedic surgeries (n = 50). METHODS: Surgical procedures were assigned to 1 of 2 groups: (1) continuous (n = 25) or (2) intermittent suction (n = 25). A control suction was operated in each surgery. Samples for aerobic and anaerobic bacteriologic examination were collected from the surgical suction at 0, 20, 60 minutes, and at the end of surgery, and from the control suction at the end of the surgery only. Comparison of continuous and intermittent suction data, and the effect of surgical time on contamination rate were analyzed using a Kaplan-Meier survival analysis followed by a Cox proportional hazards model. P < .05 was considered significant. RESULTS: Aerobic contamination occurred in 22 of 50 surgical procedures and there was no anaerobic growth. There was no significant difference between continuous and intermittent suction mode groups (P = .40). Surgical time did not influence the contamination rate (P = .79). Bacterial cultures mainly revealed coagulase-negative Staphylococci, however multiresistant bacteria were isolated. CONCLUSIONS: We failed to find superiority of the intermittent operation mode of the suction tip over the continuous mode. A safe time frame before contamination of the suction tip occurs that could not be defined.

Electromagnetic energy sources in surgery.

The biophysics, mechanism of actions, applications, benefits and complications of electromagnetic (EM) energy-based surgical instruments, and their current use are reviewed. Understanding the mechanism of action, tissue effects, and appropriate applications of EM devices is critical to achieving an optimal surgical outcome. Although a more diverse range of EM devices are used in human medicine, current use in veterinary medicine is limited to conventional electrosurgery and CO(2) lasers.

Comparison of the carbon dioxide laser and the radiofrequency unit for feline onychectomies.

This study compared the collateral tissue damage and incisional bridging with granulation tissue via histopathological examination following feline onychectomy performed by radiofrequency (RF) and carbon dioxide (CO(2)) laser. Two cats were euthanized, and their digits were harvested for histopathological evaluation on days 1, 3, and 7 post-onychectomy. Each digit was evaluated for total lesion width, total necrosis width, and degree of edema, hemorrhage, and inflammation. This study found few significant differences in collateral tissue damage between RF and CO(2) laser, but more incisional bridging by granulation tissue was noted with RF for feline onychectomies. These results indicate that RF for feline onychectomy is a reasonable alternative to CO(2) laser in regard to collateral tissue damage and bridging of the incision by granulation tissue. In addition, RF is not accompanied by the strict safety considerations and initial expense of acquisition of a CO(2) laser.

The prevalence of bacterial contamination of surgical cold sterile solutions from community companion animal veterinary practices in southern Ontario.

Surgical cold sterile solutions are commonly used in veterinary practice, yet sterility cannot be verified under practical clinical conditions. Surgical cold sterile solutions were sampled and bacteria, including opportunistic pathogens, were recovered from 13% of the sampled solutions. Attempts to sterilize surgical instruments with cold sterile solutions should be avoided.

Design and evaluation of a low-cost respiratory monitoring device for use with anaesthetized animals.

This report describes a simple, non-invasive electronic device that employs a compact accelerometer integrated circuit to transduce movements in the chest wall of an anaesthetized animal into an analogue signal that can be used to calculate the rate and relative depth of respiration. The device requires amplification by signal processing hardware/software which are common to most experimental laboratories. We assessed the sensitivity of the device by its ability to detect changes in respiratory patterns produced by modulating the depth of anaesthesia in isoflurane-anaesthetized Wistar rats. It is widely accepted that many anaesthetic agents affect respiratory patterns, especially respiratory rate (RR), which is often used as an important index of anaesthetic depth. Respiratory parameters obtained with the device were compared with concurrently recorded electroencephalographic and cardiac measures. Different concentrations of anaesthetic agent produced four depths of anaesthesia, identified using established electroencephalographic criteria. The accelerometer was attached easily and securely to the location of maximal chest wall movement and produced a strong respiratory signal that was detectable in all four anaesthetic stages. Deepening the anaesthesia produced a gradual decrease in RR, a decrease in dominant spectral frequency of the electroencephalogram (EEG) but no change in the heart rate. There was a significant correlation between RR and the dominant spectral frequency of the EEG, indicating that one useful application of the monitor could be to identify anaesthetic stages. The results demonstrate that respiratory parameters can be recorded using a simply constructed, low-cost device and suggest an application in the monitoring of anaesthetic depth.

Use of a chain écraseur for excision of a pharyngeal granuloma in a cow.

CASE DESCRIPTION: A 10-year-old Longhorn cow pregnant with a valuable fetus was evaluated because of progressive inspiratory dyspnea of 6 weeks' duration. CLINICAL FINDINGS: Physical examination findings were consistent with upper respiratory tract obstruction. A large pedunculated soft tissue mass was evident in the mid-dorsal aspect of the pharynx during palpation and endoscopic examination. Results of microscopic examination of transendoscopic fine-needle aspirates and a biopsy specimen were suggestive of a bacterial granuloma. TREATMENT AND OUTCOME: Transtracheal intubation was performed, and the mass was excised with a chain écraseur. Results of histologic examination were consistent with a diagnosis of actinobacillosis. The owner reported that the cow was doing well without any recurrence of respiratory distress 8 months after surgery. CLINICAL RELEVANCE: Findings suggested that pharyngeal granuloma resulting from actinobacillosis should be included in the differential diagnoses when examining mature cattle with upper respiratory tract obstruction and that a chain écraseur may be useful for excising soft tissue pharyngeal masses in cattle.

Outcomes of Heimlich valve drainage in dogs.

OBJECTIVE AND DESIGN: Retrospective study of the outcomes of Heimlich valve drainage in dogs. PROCEDURE: Medical records of the past 3 years were retrospectively reviewed. Heimlich valve drainage was used in 34 dogs (median body weight 30 +/- 5 kg): lobectomy (n = 15), pneumonectomy (n = 9), intrathoracic oesophageal surgery (n = 2), diaphragmatic hernia repair (n = 1), traumatic open pneumothorax (n = 2), bilobectomy (n = 2), ligation of the thoracic duct (n = 1), and chylothorax and pneumothorax (n = 1 each). Evacuation of air and/or fluid from the pleural cavity was performed with the Heimlich valve following thoracostomy tube insertion. During drainage, the dogs were closely monitored for possible respiratory failure. Termination of Heimlich valve drainage was controlled with underwater seal drainage and assessed with thoracic radiography. RESULTS: Negative intrathoracic pressure was provided in 29 dogs without any complications. Post pneumonectomy respiratory syncope and post lobectomy massive hemothorax, which did not originate from the Heimlich valve, were the only postoperative complications. Dysfunction of the valve diaphragm, open pneumothorax and intrathoracic localisation of an acute gastric dilatation-volvulus syndrome caused by a left-sided diaphragmatic hernia following pneumonectomy were the Heimlich valve drainage complications. CONCLUSIONS: The Heimlich valve can be used as a continuous drainage device in dogs, but the complications reported here should be considered by veterinary practitioners.