A scoping review on intraoperative and postoperative surgical castration complications in domesticated equids.

BACKGROUND: Castration is the most common surgical procedure in domesticated equids; surgical techniques used and perioperative management vary considerably. OBJECTIVES: To identify and chart the current evidence on perioperative complications associated with different methods of surgical castration in domesticated equids. STUDY DESIGN: Joanna Briggs Institute systematic scoping review. METHOD: CAB Abstracts, Medline and Embase databases were searched using terms related to equine castration complications. Two authors independently and blindly screened publications against eligibility criteria. Data on study methods, perioperative management, surgical techniques, and perioperative complications were extracted. Surgical techniques were grouped into categories depending on technique; open, closed or half-closed, and whether the parietal tunic was open or closed at the end of surgery. RESULTS: The search identified 1871 publications; 71 studies met the final inclusion criteria. The data reported 76 734 castrations, most of which were open or closed, with the vaginal tunic remaining open at the end of surgery. Twenty-five studies reported information regarding surgical techniques and perioperative management, allowing detailed charting and comparisons, of which analgesia and antimicrobial usage varied notably. Eighteen different complications were reported, with swelling or oedema being the most common. Evisceration was most commonly reported in draught breeds and Standardbreds, and the risk appeared low if the parietal tunic was closed at the end of surgery. MAIN LIMITATIONS: Grey literature and studies not available in English were not included. Existing studies varied greatly in perioperative management, surgical techniques and reporting of outcomes, making evidence consolidation problematic. CONCLUSION: A lack of consensus regarding complication definitions creates uncertainty and discrepancies between complication rates associated with different surgical techniques and perioperative management. The implementation of standardised systems for describing surgical techniques and complications is recommended for future studies. A number of studies did not follow current recommendations for perioperative analgesia and use of antimicrobials.

Multicenter study investigating long-term survival after synovial lavage of contaminated and septic synovial structures in horses presented to 10 UK referral hospitals.

OBJECTIVE: To report the long-term survival of adult horses that were subjected to synovial lavage for treatment of contaminated and septic synovial structures. STUDY DESIGN: Multicenter, prospective observational trial. ANIMALS: Horses (n = 240) presented for synovial sepsis at 10 UK referral centers. METHODS: Data for horses presented for treatment of synovial sepsis were collected over a 15 month recruitment period. Owners were contacted a minimum of 365 days after surgery using a structured client interview to assess long term survival. Descriptive statistics, and univariable and Cox proportional hazards models for postoperative survival time were developed. RESULTS: Survival to discharge was 228/240 (95%) and overall long-term survival was 89.4% (185/207). Unknown cause of injury (p = .017), increasing duration of surgery (p = .003), increasing weight (p = .008), forelimb injuries (p = .027), and type of synovial structure (p = .008) were found to be associated with death using Cox proportional hazards models. CONCLUSION: This study provides information on risk factors associated with survival and death after treatment for synovial sepsis at referral hospitals in the UK. Survival to discharge and long-term survival was excellent. Heavier horses, injuries affecting the forelimbs, tendon sheaths and bursae were associated with poorer long term outcomes. Longer duration of surgery was also found to be associated with a worse prognosis. CLINICAL SIGNIFICANCE: These findings help to provide prognostic information for owners and veterinarians treating horses with synovial sepsis.

Minimally invasive cranial ostectomy for the treatment of impinging dorsal spinous processes in 102 standing horses.

OBJECTIVE: To describe a minimally invasive cranial ostectomy for the treatment of impingement of dorsal spinous processes (DSPs) in the standing horse. STUDY DESIGN: Retrospective study. ANIMALS: One hundred two horses with impinging DSPs. METHODS: The case records of all horses that had the described technique between 2011 and 2019 were reviewed. All sites of impinging DSPs were treated under standing sedation and local anesthesia. The minimally invasive cranial ostectomy of the caudal DSP was performed with bone rongeurs through multiple small incisions. RESULTS: Of the 102 horses treated with this technique, no surgical complications were recorded. Median (range) long-term follow-up for all horses was 18 months (12-50 months) postoperatively. Of the 66 horses available for follow-up that were still alive, 53 horses (80%) had complete resolution of clinical signs and returned to the intended work. There were 36 horses with a concurrent orthopedic issue presurgery, and 25/36 (69%) returned to the same level of intended work; of the horses with no evidence of another orthopedic issue presurgery, 28/30 (93%) returned to the same level of intended work. CONCLUSION: Minimally invasive cranial ostectomy of the caudal DSP had a good success rate in horses with impingment of DSPs. CLINICAL SIGNIFICANCE: The described minimally invasive ostectomy technique in standing horses is a low-risk procedure that provides success rates similar to other techniques.

A scoping review of the current evidence on treatment and outcomes following synovial sepsis.

BACKGROUND: Synovial sepsis is a frequent cause of morbidity and mortality in horses. Despite advances in diagnostics and treatments, persistent infection or chronic lameness can occur. OBJECTIVES: To perform a scoping review to identify and evaluate the current evidence on the factors implicated in the success of treatment for synovial sepsis. STUDY DESIGN: Joanna Briggs Institute scoping review. METHODS: A protocol was registered, and a systematic literature search was performed on CAB abstracts, Medline, Scopus and Embase. Inclusion and exclusion criteria were developed and studies systematically reviewed against this. Studies relating to factors affecting treatment success following synovial sepsis were retained and data was extracted on study method, population characteristics and factors significantly associated with treatment outcome. RESULTS: In total, 2338 studies were identified, and 61 were included to full paper analysis. Eight papers reported significant factors, identifying 15 risk factors associated with two measurements of outcome, either survival and/or return to athletic function. The 15 factors were identified and categorised into pre-, intra- and post-operative factors. Risk factors that were identified included the number or type of synovial structures involved, the presence of pannus, tendon and bone pathology, and the use of systemic antimicrobials. There were many discrepancies in inclusion criteria of cases of synovial sepsis as well as measurement and description of outcome variables. MAIN LIMITATIONS: Non-English language studies or conference proceedings were not included. Only small numbers of papers had similar findings. CONCLUSIONS: Standardisation of inclusion criteria is essential to enable comparisons and analysis between studies on synovial sepsis. Future studies should use methodologies to reduce bias including multicentre and multinational studies, prospective study design and robust statistical modelling.

Ultrasonographic evaluation of the width, thickness, and length of the normal linea alba in standing and dorsal recumbent horses.

OBJECTIVE: To determine the variability in length, width, and thickness of the equine linea alba (LA) and the effect of a standing vs dorsal recumbent position on these measurements. STUDY DESIGN: Descriptive anatomical comparative study. ANIMALS: Standing horses (N = 75; in 30 horses, measurements were obtained in dorsal recumbency first and repeated after horses were standing). METHODS: Linea alba length was measured in standing position from xiphoid to umbilicus, and transverse ultrasonographic images were obtained at five reference points to measure LA width and thickness. In 30 horses, measurements were obtained in dorsal recumbency first and repeated after horses were standing. RESULTS: There was wide variation in LA width and thickness between standing horses, with gradual increase from xiphoid (range, 0.14-0.64 cm) to umbilicus (range, 0.2-2.97 cm). Linea alba length in standing position was 51.09 ± 6.219 cm. Width was independent of the size of the horse; thickness and length were correlated at some reference points to height (r = 0.346-585, P < .05) and weight (r = 0.324-0.642, P < .05). Different LA shapes could be identified. In dorsal recumbency, the LA was smaller in width at all reference points (15%-23%, P < .05) and shorter (20%, P < .001) compared with standing. CONCLUSION: In addition to the wide variability in LA measurements and shapes between horses, there was a significant decrease in LA width and length when horses changed from standing to dorsal recumbency. CLINICAL SIGNIFICANCE: The difference in LA length and width between dorsal recumbency and when standing could increase tension on sutures after laparotomy and should be taken into account when surgeons are closing the abdomen.

Quantitative and qualitative comparison of three scoring systems for assessing recovery quality after general anaesthesia in horses.

OBJECTIVE: To assess the reproducibility and repeatability of two commonly used recovery quality scoring systems and compare them with those of a novel system based on a greater number of objective criteria. ANIMALS: The video-recorded recoveries of ten client-owned horses selected from all recovery recordings taken between September 2005 and March 2006 at the Royal (Dick) School of Veterinary Studies. MATERIALS AND METHODS: A digital versatile disc (DVD) was produced using edited video recordings of ten horses recovering from general anaesthesia. Twelve experienced equine anaesthetists (raters) studied the DVD on three occasions, and scored the recovery quality of each horse using one of three scoring systems (P, D or E) on each occasion. The process was repeated 6 months later (t = 6) to measure intra-observer reliability (repeatability). At first use (t = 0) raters were asked to comment on the advantages and disadvantages of each system. RESULTS: Inter-rater variability was limited for each system: at each observation period raters accounted for 0.3-4.4% variation. System P was insensitive to differences between recoveries. In system D, score variability increased as recovery quality deteriorated. Intra-rater variability varied with system: using system P, raters provided consistent scores between the observation periods for some, but not all horses ('horse' and 'rater' accounted for 9.7% and 1.9% of variation respectively). Raters were less consistent between t = 0 and t = 6 using system D, but each horse was scored with similar consistency. System E produced little variation at the level of horse (1.0%) and rater (1.9%). Raters broadly agreed on the principle advantages and disadvantages of the three systems. CONCLUSIONS AND CLINICAL RELEVANCE: The systems examined showed reliability and reproducibility but practicality and simplicity of use appeared to be inextricably linked with imprecision. Further work is required to produce a suitable recovery quality scoring system.