M Kummer

Evaluation of anesthesia recovery quality after low-dose racemic or S-ketamine infusions during anesthesia with isoflurane in horses

OBJECTIVE To compare anesthesia recovery quality after racemic (R-/S-) or S-ketamine infusions during isoflurane anesthesia in horses. ANIMALS 10 horses undergoing arthroscopy. PROCEDURES After administration of xylazine for sedation, horses (n = 5/group) received R-/S-ketamine (2.2 mg/kg) or S-ketamine (1.1 mg/kg), IV, for anesthesia induction. Anesthesia was maintained with isoflurane in oxygen and R-/S-ketamine (1 mg/kg/h) or S-ketamine (0.5 mg/kg/h). Heart rate, invasive mean arterial pressure, and end-tidal isoflurane concentration were recorded before and during surgical stimulation. Arterial blood gases were evaluated every 30 minutes. Arterial ketamine and norketamine enantiomer plasma concentrations were quantified at 60 and 120 minutes. After surgery, horses were kept in a padded recovery box, sedated with xylazine, and video-recorded for evaluation of recovery quality by use of a visual analogue scale (VAS) and a numeric rating scale. RESULTS Horses in the S-ketamine group had better numeric rating scale and VAS values than those in the R-/S-ketamine group. In the R-/S-ketamine group, duration of infusion was positively correlated with VAS value. Both groups had significant increases in heart rate and mean arterial pressure during surgical stimulation; values in the R-/S-ketamine group were significantly higher than those of the S-ketamine group. Horses in the R-/S-ketamine group required slightly higher end-tidal isoflurane concentration to maintain a surgical plane of anesthesia. Moderate respiratory acidosis and reduced oxygenation were evident. The R-norketamine concentrations were significantly lower than S-norketamine concentrations in the R-/S-ketamine group. CONCLUSIONS AND CLINICAL RELEVANCE Compared with R-/S-ketamine, anesthesia recovery was better with S-ketamine infusions in horses.

Evaluation of a Motorized Morcellator for Laparoscopic Removal of Granulosa‐Theca Cell Tumors in Standing Mares

OBJECTIVE To describe a motorized morcellator technique for laparoscopic removal of granulosa-theca cell tumors (GCT) in standing mares and to evaluate long-term outcome. STUDY DESIGN Case series. ANIMALS Mares (n=7) aged 4-15 years, with unilateral GCT. METHODS Tumor size was determined by transrectal palpation and ultrasonography. Standing sedated mares had 3 laparoscopic portal sites in the paralumbar fossa. After laparoscopic observation of the GCT, the mesovarium was desensitized, the ovarian pedicle transected with a LigaSure device, and the ovary grasped with forceps and cut in cylindrical tissue blocks using a motorized morcellator. Tissue blocks were removed through the laparoscopic sleeve. Outcome was determined by telephone interview of owners 6-40 months after surgery. RESULTS Estimated ultrasonographic median GCT diameter was 17 cm (range, 10-22 cm). Surgical time was 2-4.5 hours. There were no surgical complications. Two mares had mild subcutaneous emphysema at the portals after surgery. Convalescence was short, owners were satisfied with cosmetic outcome, and clinical signs associated with GCT did not recur. CONCLUSION The motorized morcellator allows piecemeal removal of large GCT through a relatively small laparoscopic portal. Surgical complications were rare and the cosmetic outcome is favorable. CLINICAL RELEVANCE A motorized morcellator is a safe and minimally invasive technique for laparoscopic removal of GCT in mares.

Evaluation of a standardised radiographic technique of the equine hoof

Radiography of the equine hoof is often used to obtain a diagnosis. Quantitative interpretation, especially for research purposes requires high quality and accuracy of radiographs. The purpose of this study was to describe and evaluate a radiographic technique for the lateromedial (LM) and the dorsopalmar (DP) view of the equine hoof. Ten radiographs for each view from one cadaver limb and from both front feet in a standing horse were taken in order to assess repeatability of the radiographic technique. The method requires easy to use adjustable and portable equipment and strictly defined external radio opaque markers on the hoof capsule. The digitalised radiographs were processed and analysed with the software package Metron PX, measuring 13 parameters in the LM view and 10 parameters in the DP view, respectively. Results show that with few exceptions measurements of these parameters revealed a coefficient of variation that was smaller than 0.05. It was concluded that this easy to use standardised radiographic technique ensures excellent accuracy and repeatability for both the LM and DP view. Hence, this method provides an adequate tool for quantitative assessment of the equine hoof, inter- and intraindividually.

Results and complications of a novel technique for primary castration with an inguinal approach in horses

REASONS FOR PERFORMING STUDY Complications associated with equine castration can have medical and financial consequences. This retrospective study investigated a novel method of castration via an inguinal approach in mature stallions and compared the incidence of complications with other methods. HYPOTHESIS Castration via an inguinal approach has a low complication rate at the site of surgery compared with other castration techniques. METHODS Mature stallions (n = 238) were castrated under general anaesthesia in dorsal recumbency using an inguinal approach. The vaginal process was incised, the spermatic cord ligated twice and the testis removed. After suturing, the vaginal process and one or 2 layers of fascia, the subcutis and cutis were closed in a simple continuous pattern. RESULTS Five of 238 (2.1%) horses had post operative haemorrhage and a haematoma in the scrotal region, which required additional treatment. All horses made a full recovery. Five of 238 (2.1%) of the horses had a post operative respiratory infection, which resolved with antibiotic therapy. Sixteen of 238 (8.8%) had transient signs of colic shortly after surgery. CONCLUSION This technique of castration with an inguinal approach had a low incidence of complications at the site of surgery compared with other methods. An inguinal approach and leaving the vaginal tunic in situ may cause less soft tissue trauma than a scrotal approach.

Endoscopic‐Assisted Electrohydraulic Shockwave Lithotripsy in Standing Sedated Horses

Objective To report use of transendoscopic electrohydraulic shockwave lithotripsy for fragmentation of urinary calculi in horses. Study Design Case series. Animals Male horses (n = 21). Methods Fragmentation of cystic calculi (median, 6 cm diameter; range, 4–11 cm diameter) was achieved by transurethral endoscopy in standing sedated horses using an electrohydraulic shockwave fiber introduced through the biopsy channel of an endoscope. The fiber was advanced until it contacted the calculus. Repeated activation of the fiber was used to disrupt the calculus into fragments <1 cm diameter. Visibility within the bladder was maintained by repeated lavage with saline solution. Results Complete calculus removal was achieved in 20 horses (95%) with mean total surgical time of 168.6 minutes (range, 45–450). In the 20 horses with single calculi, 1–6 sessions were required to completely fragment the calculus. Except for 1 horse, in which perineal urethrotomy was eventually performed for complete fragment removal, fragments calculi were excreted via the urethra. Postoperative complications included hematuria because of severe mucosal erosion (n = 2), dysuria because of a trapped urethral fragment (2), small amount of urinary debris (1). One horse was euthanatized because of bladder rupture. Complete clearance of calculi and urinary debris was confirmed endoscopically 20 (3–45) days after the last session. Telephone follow-up (mean, 18.8 months; range, 7–24 months) revealed that horses had returned to previous activity levels without recurrence of clinical signs. Conclusions Transendoscopic electrohydraulic lithotripsy appears to be an effective method for fragmentation of low-density calcium carbonate cystic calculi in male horses.OBJECTIVE To report use of transendoscopic electrohydraulic shockwave lithotripsy for fragmentation of urinary calculi in horses. STUDY DESIGN Case series. ANIMALS Male horses (n = 21). METHODS Fragmentation of cystic calculi (median, 6 cm diameter; range, 4-11 cm diameter) was achieved by transurethral endoscopy in standing sedated horses using an electrohydraulic shockwave fiber introduced through the biopsy channel of an endoscope. The fiber was advanced until it contacted the calculus. Repeated activation of the fiber was used to disrupt the calculus into fragments <1 cm diameter. Visibility within the bladder was maintained by repeated lavage with saline solution. RESULTS Complete calculus removal was achieved in 20 horses (95%) with mean total surgical time of 168.6 minutes (range, 45-450). In the 20 horses with single calculi, 1-6 sessions were required to completely fragment the calculus. Except for 1 horse, in which perineal urethrotomy was eventually performed for complete fragment removal, fragments calculi were excreted via the urethra. Postoperative complications included hematuria because of severe mucosal erosion (n = 2), dysuria because of a trapped urethral fragment (2), small amount of urinary debris (1). One horse was euthanatized because of bladder rupture. Complete clearance of calculi and urinary debris was confirmed endoscopically 20 (3-45) days after the last session. Telephone follow-up (mean, 18.8 months; range, 7-24 months) revealed that horses had returned to previous activity levels without recurrence of clinical signs. CONCLUSIONS Transendoscopic electrohydraulic lithotripsy appears to be an effective method for fragmentation of low-density calcium carbonate cystic calculi in male horses.

Internal Fixation of a Fractured Axis in an Adult Horse

OBJECTIVE To report internal fixation of a fractured axis with a dynamic compression plate (DCP). STUDY DESIGN Case report. ANIMALS A 7-year-old Warmblood gelding. METHOD Surgery was performed under anesthesia in sternal recumbency. After fracture reduction the complete transverse fracture in the cranial third of the axis was stabilized with a 7-hole 4.5 mm DCP. Optimal positioning of the plate and the length of the screws were facilitated by fluoroscopy. Recovery from anesthesia was supervised in a pool. RESULTS The horse had an excellent outcome and returned to its previous activity level. CONCLUSION Surgical treatment with fracture reduction and plate fixation enables normal bearing of the head and neck and improves neck flexibility soon after surgery.

Locking Compression Plate Osteosynthesis of Sacral Fractures in Three Heifers

OBJECTIVE To describe a technique used for reduction and internal fixation of sacral fractures in cattle. STUDY DESIGN Case series. ANIMALS Three heifers aged 19-32 months with deformation of the tail head and tail paralysis attributable to a closed fracture of S5 or S4 and S5. METHODS Fractures were reduced and repaired under general anesthesia. A narrow, 6-10-hole, locking compression plate (LCP) was placed on the spinous processes of S5 and the first coccygeal (Co1) using 5.0 mm locking head screws. Follow-up inquiries were made by telephone (3/3), and cows were examined clinically and radiographically 2 (1 cow) to 9 (1 cow) months postoperatively. RESULTS No complications were encountered. The range of movement of the tail improved so that soiling of the tail during defecation was no longer a problem. In all heifers, the normal top line was restored and there was no narrowing of the pelvic canal. Unassisted calving occurred in all heifers, and follow-up radiographs for 2 cows showed complete fracture healing. CONCLUSION LCP-osteosynthesis of the spinous processes provided sufficient stability for internal fixation of sacral fractures. Marked improvement in tail function occurred postoperatively without decompression by laminectomy.

Arthroscopically accessible anatomy of the tarsal collateral ligaments in the horse

OBJECTIVE To describe the arthroscopically accessible anatomy of the tarsal collateral ligaments in the horse. STUDY DESIGN Descriptive study. ANIMALS Cadaveric equine hind limbs (n = 24) obtained from horses without tarsal disease. METHODS Two pairs of tarsal joints were used to obtain silicone models of the tarsocrural joint and dissect the tarsal collateral ligaments (CLs). Ten pairs of tarsocrural joints had arthroscopic exploration and the accessible parts of the tarsal CLs were marked with an arthroscopic hook knife. Subsequently, the limbs were dissected and the marked positions were allocated to the specific parts of the CLs. RESULTS Ipsilateral arthroscope and instrument portals were used in each pouch of the tarsocrural joint. Via the plantaromedial pouch, the superficial (2/20 limbs), middle (7), deep (6) or both middle and deep (3) short medial CL and the long medial CL (14) were reached. Access via the plantarolateral pouch allowed manipulation of the deep short lateral CL (20/20 limbs) and the long lateral CL (20). Dorsally, arthroscopy via the dorsomedial pouch gave access to the deep short medial CL (20/20 limbs), while the superficial (9) or middle (10) or both superficial and middle (1) short lateral CL could be reached via the dorsolateral joint recess. CONCLUSIONS Limited parts of the tarsal CLs can be observed or manipulated arthroscopically in normal equine tarsocrural joints.

Bilateral Iatrogenic Maxillary Fractures after Dental Treatment in Two Aged Horses

This clinical report describes two horses with bilateral maxillary fractures following dental treatment. The fractures occurred during dental treatment by a veterinarian, and both had rostral, transverse, and complete bilateral maxillary fractures with instability and minimal displacement. The fractures were repaired using bilateral intraoral wiring with the patients under general anesthesia. The postoperative period was without complications and the fractures healed as expected. Maxillary fractures during or after routine dental treatment are rare, but can occur, especially in older horses. Appropriate sedation and, if necessary, regional nerve blocks might reduce the risk of iatrogenic fractures of the maxilla. General anesthesia must be considered for tooth extraction in horses that are difficult to restrain.

Sind die Hornspalten ein oberflächliches Hufproblem

Es werden 54 Pferde mit einem oder mehreren Hornspalten beschrieben, die an die Pferdeklinik der Universitat Zurich uberwiesen wurden. Die Pferde wurden wegen Lahmheiten oder anderen Symptomen vorgestellt. Die am haufigsten vorkommende Form war die perforierende Trachtenwandhornspalte. Verletzungen im Bereich des Kronrandes spielen als Ursache eine geringe Bedeutung, wahrend Stellungs- und Formabweichungen der Hufkapsel eine wichtige Rolle bei der Entstehung der Hornspalten einnehmen. Fur die Behandlung der Hornspalten sind eine Beschlagskorrektur, das Ausschleifen des Hornspaltes selber sowie eine stabile Fixation sehr wichtig. Trotzdem ist die Rezidivrate mit 20% sehr hoch.