Variables associated with the prevalence of self-reported work-related musculoskeletal disorders in veterinary laparoscopic surgeons.

OBJECTIVE: To investigate the relationship between physical attributes and difficulty performing laparoscopic maneuvers with the prevalence of self-reported musculoskeletal injury. STUDY DESIGN: Online survey. SAMPLE POPULATION: Surgeons (n = 140) with 3 or more years of laparoscopic experience. METHODS: Electronic survey distributed via LISTSERVEs and Facebook groups. Responses collected included surgeon attributes, presence of musculoskeletal injuries, and surgical practice data. Statistical analysis was performed using the Shapiro-Wilk test, linear regression, logistic regression, and Wilcoxon rank sum tests. RESULTS: A total of 52 of the 140 respondents reported a musculoskeletal injury with 38 specifying at least one injury (72%). Neck strain was the most prevalent reported musculoskeletal injury (18/52, 34.6%), followed by shoulder tendinopathies (16/52, 30.8%), arm/hand tendonitis (8/52, 15.4%), carpal tunnel (7/52, 13.5%), back pain (4/52, 7.7%) and arm/hand arthritis (1/52, 1.9%). Women were significantly more likely to report a musculoskeletal problem than men (p = .011) with the odds of women reporting a musculoskeletal injury 2.59 times greater than men. Women and surgeons with smaller glove sizes were significantly more likely to report shoulder tendonitis (p = .034, p = .1) and neck strain (p = .009, p = .001). Respondents with a musculoskeletal problem experienced significantly more difficulty using rotating cup biopsy forceps (p < .001) and perceived this as difficult a greater amount of time (p = .006). CONCLUSION: Female surgeons report more musculoskeletal injuries than their male counterparts. Surgeons with musculoskeletal injuries experience more difficulty performing particular laparoscopic maneuvers. CLINICAL SIGNIFICANCE: Improving ergonomics for women and surgeons with smaller glove sizes must be prioritized to improve surgeon health and laparoscopic instrument use.

Variables affecting surgeons' use of, and preferences for, instrumentation in veterinary laparoscopy.

OBJECTIVE: To investigate the impact of variables on use and preference of common laparoscopic instruments. STUDY DESIGN: Online survey. SAMPLE POPULATION: Surgeons (n = 140) with 3 years or more laparoscopic experience. METHODS: Electronic survey distributed via specialty group LISTSERVEs and Facebook groups. Responses collected included surgeon attributes, preferences, and surgical practice data. Statistical analysis was performed using Fishers exact, ANOVA, Tukey Kramer honestly significant difference (HSD) test, linear regression, and logistic regression. RESULTS: Ninety-eight of 140 respondents answered instrument-related questions and the completion rate of these questions was 76%: 48% of females and 49% of males responded to the survey. The median glove size of respondents was size 7 (range, 5.5 to 8.5). Closing laparoscopic Babcock forceps (p = .018), rotating cup biopsy forceps (p = .003), and manipulating endoscopic staplers (p < .001) were more difficult for surgeons with smaller glove sizes. The median difficulty score for the endoscopic stapler was 4/10 and the median percentage of time this was found difficult was 25%. Reusable instruments were preferred over disposable single-use instruments. The pistol grip was preferred for grasping and retracting (54/98, 55%) and fine dissection (46/96, 48%), while the axial grip was preferred for suturing and knot tying (61/98, 62%). CONCLUSION: Surgeons with smaller glove sizes (<6.5) experience more difficulty when using common laparoscopic instruments. The endoscopic stapler was the most difficult to use. CLINICAL SIGNIFICANCE: When purchasing laparoscopic instrumentation, surgeons should review all available options in handle size and design to improve ergonomics during minimally invasive procedures.

Comparison of ultrasound-guided and landmark-based techniques for central venous catheterization via the external jugular vein in healthy anesthetized dogs.

OBJECTIVE To compare time to achieve vascular access (TTVA) between an ultrasound-guided technique (UST) and landmark-based technique (LMT) for central venous catheter (CVC) placement in healthy anesthetized dogs. ANIMALS 39 purpose-bred hounds. PROCEDURES Anesthetized dogs that were hemodynamically stable following completion of a terminal surgical exercise were enrolled in the study during 2 phases, with a 45-day intermission between phases. For each dog, a UST and LMT were used for CVC placement via each external jugular vein by 2 operators (criticalist and resident). The TTVA and number of venipuncture attempts and catheter redirections were recorded for each catheterization. Placement of the CVC was confirmed by contrast fluoroscopy. After euthanasia, a gross dissection was performed during which a hematoma score was assigned to the catheter insertion site. For each phase, nonlinear least squares estimation was used for learning curve analysis of the UST. RESULTS Median TTVA, number of venipuncture attempts and catheter redirections, and hematoma score did not differ significantly between the 2 operators for either technique. Median TTVA for the UST (45 seconds) was significantly longer than that for the LMT (7 seconds). Learning curve analysis indicated that 8 and 7 UST catheterizations were required to achieve performance stability in phases 1 and 2, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the UST was comparable to the LMT for CVC placement in healthy dogs. The extra time required to perform the UST was not clinically relevant. Additional studies evaluating the UST for CVC placement in clinically ill dogs are warranted.

Evaluation of learning curves for ovariohysterectomy of dogs and cats and castration of dogs.

OBJECTIVE To define learning curves for fourth-year veterinary students performing ovariohysterectomy procedures in dogs and cats and castration in dogs. DESIGN Retrospective study. SAMPLE 3,196 ovariohysterectomies or castrations performed in dogs and cats by 88 veterinary students during a spay-neuter surgery and animal shelter rotation (n = 3,056) or by 1 experienced general practitioner (n = 140). PROCEDURES Data collected from medical records included patient signalment, type and duration of procedure, and sequence (by date and time) of the procedure within a list of procedures of the same type generated for each student. For each procedure type, geometric mean surgery time and 95% confidence intervals were determined for each number of surgeries completed by ≥ 10 students. Median surgery times for the same procedure types were determined for the experienced practitioner. The learning curve for each procedure was modeled with nonlinear (3-factor exponential equation with a nonzero asymptote) and linear regression. For each procedure, the asymptote (optimal surgery time) for students was compared with the experienced practitioner's median surgery time. RESULTS 2,945 surgeries (mean, 33/student) performed by ≥ 10 students were analyzed. Surgery time decreased in a nonlinear manner as student experience increased for castration of adult or pediatric dogs and ovariohysterectomy of pediatric dogs and adult or pediatric cats. Surgery time decreased in a linear manner as experience increased for ovariohysterectomy of adult dogs. CONCLUSIONS AND CLINICAL RELEVANCE To the authors' knowledge, this was the first study to map surgery times for common surgical procedures consecutively performed by veterinary students. Results clearly indicated the value of repetition to improve surgical skills (as measured by surgery time) during a 3-week period.

Single layer cystotomy closure of excised porcine bladders with barbed versus smooth suture material.

OBJECTIVE: To determine which of 2 suture materials would be superior in terms of closure time and leakage pressure in open single-layer cystotomy closure. STUDY DESIGN: Experimental study. ANIMALS: Twenty-four freshly harvested porcine urinary bladders. METHODS: A cystotomy was performed and the incision closed with a single layer simple continuous suture pattern with barbed (n = 12) or smooth (n = 12) suture. Time required for closure was measured. Each bladder was connected to a system for monitoring intraluminal pressure while inflated with saline until leakage occurred. Intraluminal pressure at time of initial leakage and leakage site were recorded. Two-sample t tests were used to compare maximum leakage pressure and closure time between the 2 groups. P < .05 was considered significant. RESULTS: All bladders were sutured successfully with no difference in mean closure time (barbed suture 296 ± 46 seconds; smooth suture 293 ± 26 seconds) (P = .821). There was no difference in mean leakage pressure of porcine urinary bladder incisions closed in a single layer with barbed suture (28.8 ± 10.4 mm Hg) compared with smooth suture (30.6 ± 8.8 mm Hg) (P = .642). CONCLUSIONS: Barbed suture provides comparable cystotomy repair to smooth suture, and no benefit to its use was identified in an open procedure. Barbed suture closure should be evaluated for adequate tensile strength in the presence of urine, satisfactory in vivo healing of cystotomies, and lack of long-term urolith formation in dogs and cats.

Effects of topical application of silver sulfadiazine cream, triple antimicrobial ointment, or hyperosmolar nanoemulsion on wound healing, bacterial load, and exuberant granulation tissue formation in bandaged full-thickness equine skin wounds.

OBJECTIVE To determine the effects of 3 topically applied treatments (1% silver sulfadiazine cream [SSC], triple antimicrobial ointment [TAO], and hyperosmolar nanoemulsion [HNE]) on microbial counts, exuberant granulation tissue (EGT) development, and reepithelialization of contaminated wounds at the distal aspect of the limbs of horses. ANIMALS 8 healthy adult horses. PROCEDURES A 2.5 × 2.5-cm, full-thickness, cutaneous wound was created at the dorsal aspect of each metacarpus and metatarsus (1 wound/limb/horse), covered with nonadhesive dressing, and bandaged. Wounds were inoculated with bacteria and fungi the next day. Each wound on a given horse was randomly assigned to 1 of 4 treatment groups (SSC, TAO, HNE, or no topical treatment [control]). Bandage changes, culture of wound samples, treatments, photography for wound measurements, and biopsy were performed at predetermined time points. Time (days) until wound closure, number of EGT excisions, microbial counts, and scores for selected histologic characteristics were compared among groups. RESULTS Median time to wound closure for all groups was 42 days. Time to wound closure and histologic characteristics of wound healing did not differ among groups. Least squares mean microbial counts were significantly higher for HNE-treated wounds on days 9 and 21, compared with SSC-treated and TAO-treated wounds, but not controls. Proportions of SSC-treated (7/8) or HNE-treated (5/8) wounds needing EGT excision were significantly greater than that of TAO-treated (1/8) wounds. The proportion of SSC-treated wounds with EGT excision was greater than that of controls (3/8). CONCLUSIONS AND CLINICAL RELEVANCE None of the treatments resulted in more rapid wound closure, compared with that for untreated control wounds under the study conditions. When treatment is warranted, TAO may help to limit EGT formation.

Teaching veterinary anesthesia and surgery: the impact of instructor availability on anesthesia, operative, and recovery times in dogs undergoing ovariohysterectomy or castration.

Veterinary students learning to perform elective ovariohysterectomy (OVH) and castration procedures have traditionally been taught by a few instructors supervising many student groups simultaneously. This study, using a historical control group, explored the impacts of having a dedicated instructor with each student group for anesthetic induction and an entire surgical procedure. Our hypothesis was that preparation, surgical, and anesthesia times would be shorter and, consequently, post-operative recovery times would be shorter with a dedicated instructor compared to traditional methods. Anesthesia records of dogs undergoing elective surgery by third-year veterinary students were reviewed over 3 consecutive years. Traditional instruction was used in year 1 (Y1), and a dedicated instructor per student group was used in year 2 (Y2) and year 3 (Y3). Anesthesia time, surgical time, recovery time, and pre- and post-operative rectal temperature were analyzed, and a stepwise regression model was developed for factors influencing recovery time. Of 206 records reviewed (Y1, 33; Y2, 98; Y3, 75), there were 101 OVH procedures and 105 castration procedures. Preparation, surgery, and anesthesia times were longer in animals undergoing surgery in Y1, when the traditional instruction method was used. Recovery time was not influenced by instructor assignment. Using dedicated instructors to teach OVH and castration to third-year veterinary students decreased overall anesthesia time by 36 to 49 minutes for OVH and 29 to 32 minutes for castration. A teaching model of dedicated instructors requires excellent coordination between surgeons and anesthesiologists to ensure that a similar number of animals can undergo procedures in the time allotted for teaching.

Biofilm-infected wounds in a dog.

CASE DESCRIPTION: A 4-year-old spayed female Mastiff was evaluated for treatment of chronic nonhealing pressure wounds over both elbow regions resulting from attempts at hypertrophic callus excision. CLINICAL FINDINGS: The wound bed granulation tissue was mottled red and yellow with hyperemic, rolled epithelial edges. The right wound communicated with a large fluid pocket along the thoracic wall. The dog had an inflammatory leukogram with a left shift. TREATMENT AND OUTCOME: The wounds were debrided, and tissue specimens were collected for histologic evaluation, microbial culture, and bacterial identification by means of molecular diagnostic techniques. The left wound was closed immediately. Calcium alginate rope with silver was packed into the right wound. Vacuum-assisted closure was applied for 6 days. Debridement was repeated, and a thoracodorsal axial pattern flap was used to cover the wound. Systemic treatment with antimicrobials was initiated, and pressure over the elbow regions was relieved. Bacterial biofilms were identified histologically in tissue specimens from both wounds. Staphylococcus intermedius, Staphylococcus epidermidis, and Streptococcus canis were cultured and identified by 16S rRNA fragment sequencing. Pyrosequencing identified multiple bacterial species and no fungal organisms. Both wounds healed successfully. CLINICAL RELEVANCE: Biofilms are implicated in infected orthopedic implants in veterinary patients; however, this is the first report of a bacterial biofilm in chronic wounds in a dog. In human wound care, extensive debridement is performed to disrupt the biofilm; a multimodal treatment approach is recommended to delay reformation and help clear the infection. In this case, biofilm reformation was prevented by systemic treatment with antimicrobials, by reducing local pressure on the wounds, and by wound closure.

Service learning: Priority 4 Paws mobile surgical service for shelter animals.

The increasing attention given to competencies needed to enter the workforce has revealed a need for veterinary students to gain more experience in performing small-animal elective surgery before graduation. In addition, guidelines for standards of care for shelter animals recommend that all dogs and cats should be spayed or neutered before adoption. Teaching surgical skills while serving the needs of local animal shelters represents an ideal service-learning opportunity. Following a pilot study and the benchmarking of other programs, an elective course in shelter medicine and surgery was created at Purdue University College of Veterinary Medicine (PVM) to allow senior DVM students an opportunity to spend 2 weeks on a mobile surgery unit (Priority 4 Paws) and 1 week at an animal shelter. With financial assistance from sponsors and donors, PVM purchased and equipped a mobile surgery unit, hired a full-time veterinarian and a registered veterinary technician, and established relationships with 12 animal shelters. From July 30, 2012, to March 22, 2013, 1,941 spays and neuters were performed with excellent postsurgical outcomes while training 33 veterinary students on rotation and 26 veterinary technician students. The program was well accepted by both students and the shelters being served. The Priority 4 Paws program is an example of an integrated, community-based service-learning opportunity that not only helps to improve the surgical skills of veterinary students but also helps to meet an identified community need.

Deep sedation in natural orifice transluminal endoscopic surgery (NOTES): a comparative study with dogs.

BACKGROUND: Natural orifice transluminal endoscopic surgery (NOTES) has been mostly performed with the animal under general and inhalational anesthesia (IA-NOTES). To date, NOTES using propofol sedation (PS-NOTES) has not been investigated. This study aimed to assess the feasibility and safety of PS-NOTES for transgastric oophorectomy with carbon dioxide insufflation and to compare its success rates with those of conventional IA-NOTES. METHODS: In this prospective randomized study, NOTES oophorectomy was performed for 19 female dogs randomized to two conditions: PS (study group) and IA (control group). Sedation success rates (ability to visualize and resect ovaries without converting to IA), operative success rates (ability to resect and retrieve both ovaries in full using only NOTES), and vital parameters including hemodynamic and respiratory changes were documented. RESULTS: In the PS-NOTES group (n = 9), the sedation success rate was 100 %. The operative success rate was 67 % (6 of 9 animals) compared with 80 % (8 of 10 animals) in the IA-NOTES group. No purposeful movement occurred during surgical manipulation and no respiratory or cardiovascular complications in occurred the PS group. Heart rate (HR) and end-tidal carbon dioxide (ETCO(2)) were significantly higher in the PS group than in the IA group. Blood pressure (BP) was significantly higher in the PS group only during the middle part of the procedure. Only mild respiratory depression was noted in the PS group, as indicated by elevated but acceptable ETCO(2). Elevations in BP and HR are thought to be related to elevated CO(2) but did not appear to have an adverse impact on the course of the procedure. Recovery was uneventful for all the animals. CONCLUSION: The use of PS-NOTES appears to be feasible, resulting in outcomes comparable with those for IA in dogs. Further studies are needed to determine the applicability of this concept in human NOTES.

Transdiaphragmatic extension of a retroperitoneal lipoma into the intrathoracic extrapleural space via the lumbocostal trigone in a dog.

CASE DESCRIPTION: An 8-year-old 12.2-kg (26.9-lb) spayed female American Cocker Spaniel was referred for evaluation of abdominal discomfort and a suspected intra-abdominal lipoma with possible invasion into the thorax. CLINICAL FINDINGS: Physical examination revealed a tense abdomen, and the margins of a large abdominal mass could be appreciated. Abdominal imaging revealed a mass of fat opacity in the abdominal and thoracic cavities. Computed tomography with precontrast and postcontrast peritoneograms was used to determine whether the masses connected via a diaphragmatic defect. TREATMENT AND OUTCOME: Exploratory laparotomy revealed a retroperitoneal lipomatous mass that had focally invaded the hypaxial musculature and had extended across the dorsolateral aspect of the diaphragm via the lumbocostal trigone into the intrathoracic extrapleural space. Surgical resection required transdiaphragmatic thoracotomy. Histologic examination of excised tissue confirmed the preoperative diagnosis of a lipoma. The dog recovered from surgery with no complications and had no disease recurrence for at least 32 months after surgical resection. CLINICAL RELEVANCE: The defect of the lumbocostal trigone is also called the foramen of Bochdalek in humans, and it is recognized as a common location for congenital diaphragmatic hernia. A lumbocostal trigone hernia may be considered as a differential diagnosis for bicavitary masses in dogs, particularly in the absence of a history of trauma.

Pilot evaluation of a vacuum-assisted biopsy instrument for percutaneous renal biopsy in dogs.

Kidney biopsies in dogs are commonly obtained using automated spring-loaded biopsy instruments. Interpretation of biopsies from dogs with glomerular disease requires examination of at least 5-10 glomeruli, with at least two biopsies usually required for full evaluation. The purpose of this study was to compare quality and interpretability of renal biopsies obtained from healthy dogs with a large-gauge, vacuum-assisted biopsy instrument versus two biopsies obtained with a spring-loaded biopsy needle. Twenty dogs were randomized into two groups, and percutaneous, ultrasound-guided renal biopsies were evaluated using standard criteria. There were no significant differences in the number of biopsies that contained renal tissue, cortex, or medulla. Biopsies obtained with either instrument contained an adequate number of glomeruli and an equivalent number of arterioles and severity of tissue compression. Differences included easier penetration of the renal capsule and collection of sufficient tissue for interpretation with only one instrument pass when using the vacuum-assisted device (vs two passes required with the spring-loaded instrument). Before use in client-owned dogs, future studies should evaluate whether these differences are clinically relevant advantages in the diagnostic evaluation of dogs with kidney disease, and determine the prevalence and severity of complications when using this larger gauge device.

Comparison of transvaginal natural orifice transluminal endoscopic surgery (NOTES®) and laparoscopy for elective bilateral ovariectomy in standing mares.

OBJECTIVE: To compare surgical trauma, perioperative pain, surgical time, and complication rate in mares undergoing standing bilateral ovariectomy by natural orifice transluminal endoscopic surgery (NOTES) or laparoscopy. STUDY DESIGN: Experimental study. ANIMALS: Healthy mares (n = 12). METHODS: Ovariectomy was performed with a vessel-sealing device by transvaginal NOTES (n = 6) using a flexible endoscope and specialized instruments or by bilateral flank laparoscopy (n = 6). Preoperative and postoperative complete blood count (CBC), plasma fibrinogen concentration, serum amyloid A concentration, peritoneal nucleated cell count, and total protein concentration were compared using repeated measures ANOVA. Surgical times were compared using an unpaired t-test. Mares were monitored for 2 weeks postoperatively and necropsy was performed at 3 weeks (n = 6) or 3 months (n = 6) to assess short- and medium-term effects of each procedure. Complication rate, necropsy, and bacteriology findings were compared using a Fishers exact test. Significance was set at P < .05. RESULTS: All surgical procedures were performed successfully and all but one laparoscopy mare were bright, alert, and maintained a good appetite until euthanasia. Mean ± SD surgical time was similar between groups (NOTES: 100 ± 40 minutes; laparoscopy: 107 ± 47 minutes). There were no significant temporal differences in vital parameters, CBC, plasma fibrinogen concentration, serum amyloid A concentration, peritoneal nucleated cell count, and total protein concentration between groups. CONCLUSIONS: Bilateral ovariectomy by transvaginal NOTES or laparoscopy resulted in minimal inflammation and surgical trauma.

Standing ovariectomy in mares using a transvaginal natural orifice transluminal endoscopic surgery (NOTES®) approach.

OBJECTIVE: To develop and assess the feasibility of standing transvaginal Natural Orifice Transluminal Endoscopic Surgery (NOTES®) ovariectomy in the mare. STUDY DESIGN: Descriptive study. ANIMALS: Mares (n=10). METHODS: The technique was developed in 6 mares and then evaluated in a short-term study in 4 mares. Abdominal access was developed using controlled access vaginal cannula placement under endoscopic guidance. With viewing provided by a flexible endoscope, hemostasis, and transection of ovarian pedicles was performed using a customized bipolar vessel-sealing device. The ovaries were retrieved and the colpotomy was sutured. Surgical time, intra-, and postoperative complications were recorded. Necropsy was performed immediately after surgery in 6 mares and 15 days after surgery in 4 mares to assess short-term complications. RESULTS: After the instruments and techniques were developed, transvaginal NOTES® ovariectomy was successfully performed. Analgesia during the procedure was adequate in all cases. The visual field provided by the endoscope was acceptable. The customized 60 cm vessel-sealing device provided good hemostasis and a comfortable working length. Intraoperative complications included difficult viewing that prolonged operative time and inability to remove the second ovary in 1 mare. Postoperative recovery was excellent. Postmortem findings of 1 true positive microbial culture, elevated cell counts in abdominal fluid, and adhesion formation raise questions that must be addressed in future studies. CONCLUSION: Using specialized instruments, transvaginal NOTES® ovariectomy is technically feasible in mares.

Results of biopsy via transurethral cystoscopy and cystotomy for diagnosis of transitional cell carcinoma of the urinary bladder and urethra in dogs: 92 cases (2003-2008).

OBJECTIVE: To assess the diagnostic utility of transurethral cystoscopic biopsy in dogs with histologically confirmed transitional cell carcinoma (TCC) of the urinary bladder and urethra. DESIGN: Retrospective case series. ANIMALS: 92 dogs with histologically confirmed TCC. PROCEDURES: Information on sex, breed, neuter status, body weight, tumor location, biopsy method, number of biopsy procedures, experience level of clinician performing biopsy, and quality of biopsy sample was obtained from medical records. The association of variables with likelihood of achieving a diagnostic-quality biopsy sample was evaluated by use of logistic regression. RESULTS: If used as the initial biopsy method, cystoscopic biopsy samples were of diagnostic quality in 65% of male dogs and 96% of female dogs with histologically confirmed TCC. Cystoscopic biopsy samples were significantly more likely to be of diagnostic quality in female dogs than in male dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Cystoscopic biopsy is an effective method to obtain biopsy samples in dogs with TCC of the bladder and urethra. Cystoscopy is more likely to produce a diagnostic-quality biopsy sample in female dogs with TCC than in male dogs with TCC. Cystoscopy should be considered as a primary means of biopsy in male and female dogs with masses of the urinary bladder or urethra.

An alternative pathway electrosurgical unit injury in a dog.

OBJECTIVE: To report esophageal perforation, caused by alternative current pathway from the use of a monopolar electrosurgery unit (ESU), during routine orthopedic surgery in a dog. STUDY DESIGN: Clinical report. ANIMALS: Two-year-old male Labrador retriever. METHODS: Medial meniscectomy and lateral suture stabilization were performed on a healthy Labrador retriever with a ruptured cranial cruciate ligament. Monopolar electrosurgery was used during the procedure for hemostasis and tissue dissection. Anesthetic monitoring was augmented with an esophageal electrocardiogram (ECG) probe. The day after surgery, the dog appeared dehydrated. After intravenous fluid therapy, respiratory distress was noted and thoracic radiography and contrast fluoroscopy revealed an esophageal perforation. RESULTS: Exploratory surgery was planned to repair the defect. Cardiac arrest occurred after induction. Gross necropsy findings and histopathologic examination revealed lesions consistent with thermal necrosis of the esophagus and myocardial degeneration. An internal investigation of this medical device accident revealed that multiple factors may have contributed to the injury. CONCLUSIONS: An alternative current pathway from the monopolar ESU to the esophageal ECG probe resulted in a full-thickness esophageal thermal injury and cardiac failure.

Efficacy of oral transmucosal and intravenous administration of buprenorphine before surgery for postoperative analgesia in dogs undergoing ovariohysterectomy.

OBJECTIVE: To compare the efficacy of preoperative administration of buprenorphine (via oral transmucosal [OTM] and IV routes) for postoperative analgesia in dogs undergoing ovariohysterectomy. DESIGN: Prospective, randomized, blinded study. ANIMALS: 18 dogs undergoing routine ovariohysterectomy. PROCEDURES: Dogs were allocated to 3 groups (6 dogs/group) and were assigned to receive buprenorphine (20 µg/kg [9.09 µg/lb], IV; a low dose [20 µg/kg] via OTM administration [LOTM]; or a high dose [120 µg/kg [54.54 µg/lb] via OTM administration [HOTM]) immediately before anesthetic induction with propofol and maintenance with isoflurane for ovariohysterectomy. Postoperative pain was assessed by use of a dynamic interactive pain scale. Dogs were provided rescue analgesia when postoperative pain exceeded a predetermined threshold. Blood samples were collected, and liquid chromatography-electrospray ionization-tandem mass spectrometry was used to determine plasma concentrations of buprenorphine and its metabolites. Data were analyzed with an ANOVA. RESULTS: Body weight, surgical duration, propofol dose, isoflurane concentration, and cardiorespiratory variables did not differ significantly among treatment groups. Number of dogs requiring rescue analgesia did not differ significantly for the HOTM (1/6), IV (3/6), and LOTM (5/6) treatments. Similarly, mean ± SEM duration of analgesia did not differ significantly for the HOTM (20.3 ± 3.7 hours), IV (16.0 ± 3.8 hours), and LOTM (7.3 ± 3.3 hours) treatments. Plasma buprenorphine concentration was ≤ 0.60 ng/mL in 7 of 9 dogs requiring rescue analgesia. CONCLUSIONS AND CLINICAL RELEVANCE: Buprenorphine (HOTM) given immediately before anesthetic induction can be an alternative for postoperative pain management in dogs undergoing ovariohysterectomy.

Identification of low and high frequency ranges for heart rate variability and blood pressure variability analyses using pharmacological autonomic blockade with atropine and propranolol in swine.

Understanding autonomic nervous system functioning, which mediates behavioral and physiological responses to stress, offers great potential for assessing farm animal stress and welfare. Evaluation of heart rate variability (HRV) and blood pressure variability (BPV), using time and frequency domain analyses may provide a sensitive and reliable measure of affective states and stress-mediated changes in sympathetic and parasympathetic tones. The aim of this research was to define low (LF) and high frequency (HF) power spectral ranges using pharmacological autonomic blockade, and to examine HRV and BPV parameter changes in response to atropine and propranolol in swine. Ten, 13-week old, barrows (n=6) and gilts (n=4) underwent surgery to place an intra-cardiac electrode and a blood pressure catheter attached to a biotelemetric transmitter; pigs had a 3-week recovery period prior to data collection. Each pig was subjected to administration of 4 intravenous (i.v.) drug treatments: a control treatment, 3 mL of saline, and 3 blockade treatments; 0.1 mg/kg of atropine, 1.0 mg/kg of propranolol, and .1 mg/kg of atropine together with 1.0 mg/kg of propranolol. All treatments were delivered by injection in the jugular vein with a minimum of 48 h between individual treatments. Behavior, ECG and blood pressure data were recorded continuously for a total of 1h, from 30 min pre-injection to 30 min post-injection. For data analyses, two 512-beat intervals were selected for each treatment while the pig was lying and inactive. The first interval was selected from the pre-injection period (baseline), and the second was selected between 10 and 30 min post-injection. Time and frequency domain (power spectral density) analyses were performed on each data interval. Subsequent, LF and HF bands from the power spectral densities were defined based on general linear and regression analyses. The HRV and BPV were computed with a covariate (baseline) factorial analysis of treatment by sex interaction, and day of injection, with mixed models and Tukey's post-hoc tests. The best-fit range for LF was 0.0-0.09 Hz, and HF was 0.09-2.0 Hz (r²: 0.41 and 0.43, respectively). Propranolol and saline injections led to a greater overall total power and overall higher inter-beat interval, HF and LF power. Atropine led to a dominant sympathovagal balance of the cardiac activity in pigs. In addition, atropine led to an increase in LF power of both systolic and diastolic blood pressures in gilts suggesting vagal tone mediation of BPV. The understanding of autonomic regulation of HRV and BPV in domestic swine facilitates our ability to detect and quantify stress responses, and broadens its application in assessing farm animal welfare.

Evaluation of minimally invasive excisional brain biopsy and intracranial brachytherapy catheter placement in dogs.

OBJECTIVE: To evaluate a technique for minimally invasive excisional brain biopsy and intracranial brachytherapy catheter placement in dogs. ANIMALS: 5 healthy adult female dogs. PROCEDURES: Computed tomographic guidance was used to plan a biopsy trajectory to a selected area of brain with reference to a localizer grid. The procedure was performed through a 1-cm skin incision and 6-mm burr hole by use of a 9-gauge biopsy device. Five cylindrical samples (3 to 4 mm in diameter and 7 to 12 mm in length) were removed over 5 cycles of the vacuum-assisted tissue excision system, leaving approximately a 2-cm³ resection cavity. A balloon-tipped intracranial brachytherapy catheter was placed through the burr hole into the resection cavity, expanded with saline (0.9% NaCl) solution, and explanted 7 days later. RESULTS: 4 of 5 dogs survived the procedure. The fifth died because of iatrogenic brain damage. Neurologic deficits were unilateral and focal. Twenty-four hours after surgery, all surviving dogs were ambulatory, 2 dogs exhibited ipsiversive circling, 4 had contralateral proprioceptive deficits, 3 had contralateral menace response deficits, 2 had a reduced contralateral response to noxious nasal stimulation, and 1 had dull mentation with intermittent horizontal nystagmus and ventrolateral strabismus. Neurologic status improved throughout the study period. Histologic quality of biopsy specimens was excellent. CONCLUSIONS AND CLINICAL RELEVANCE: This technique enabled histologic diagnosis from high-quality biopsy specimens obtained through a minimally invasive technique and has potential applications for multimodal treatment of deep brain tumors in dogs.

Feasibility of contrast-enhanced ultrasound-guided biopsy of sentinel lymph nodes in dogs.

Our goal was to develop and validate a technique to identify the sentinel lymph nodes of the mammary glands of healthy dogs with contrast-enhanced ultrasound, and evaluate the feasibility of obtaining representative samples of a sentinel lymph node under ultrasound guidance using a new biopsy device. Three healthy intact female adult hounds were anesthetized and each received an injection of octafluoropropane-filled lipid microspheres and a separate subcutaneous injection of methylene blue dye around a mammary gland. Ultrasound was then used to follow the contrast agent through the lymphatic channel to the sentinel lymph node. Lymph node biopsy was performed under ultrasound guidance, followed by an excisional biopsy of the lymph nodes and a regional mastectomy procedure. Excised tissues were submitted for histopathologic examination and evaluated as to whether they were representative of the node. The ultrasound contrast agent was easily visualized with ultrasound leading up to the sentinel lymph nodes. Eight normal lymph nodes (two inguinal, one axillary in two dogs; two inguinal in one dog) were identified and biopsied. Lymphoid tissue was obtained from all biopsy specimens. Samples from four of eight lymph nodes contained both cortical and medullary lymphoid tissue. Contrast-enhanced ultrasound can be successfully used to image and guide minimally invasive biopsy of the normal sentinel lymph nodes draining the mammary glands in healthy dogs. Further work is needed to evaluate whether this technique may be applicable in patients with breast cancer or other conditions warranting evaluation of sentinel lymph nodes in animals.