Effectiveness of chlorhexidine diacetate and povidone-iodine in antiseptic preparation of the canine external ear canal prior to total ear canal ablation with bulla osteotomy procedure: A preliminary study

OBJECTIVE

This article is a preliminary study to compare the ability of 0.05% chlorhexidine diacetate (CD) and 1% povidone-iodine (PI) solutions to reduce bacterial contamination on the canine external ear canal during initial patient preparation and comparison of the incidence of immediate tissue reactions.

STUDY DESIGN

The study is a multi-institutional, randomised, clinical prospective study.

ANIMALS OR SAMPLE POPULATION

Dogs (n = 19) undergoing total ear canal ablation with bulla osteotomy (TECABO).

METHODS

The external ear of each dog was cleaned with the assigned antiseptic solution. Culture of the ear was performed by standard techniques to semi-quantitatively evaluate bacterial growth and to identify bacterial organisms pre- and post-antiseptic use.

RESULTS

Both antiseptic groups showed a significant reduction in bacterial growth score (BGS) between pre- and post-antiseptic use (CD p = 0.009, PI p = 0.005). There was no difference in the reduction of BGS between CD and PI solutions (p = 0.53). Minor adverse skin reactions occurred in 25% of cases. There was no significant difference in the occurrence of adverse skin reactions between antiseptics (p = 0.63).

CONCLUSION

CD and PI were similarly able to decrease the number of bacteria on the external ear following initial preparation. No difference in the incidence of adverse tissue reactions was found.

CLINICAL SIGNIFICANCE

Properly diluted aqueous formulations of either antiseptic may be used for safe preparation limited to the external ear canal of dogs. Additional studies evaluating outcomes such as duration of bacterial inhibition and incidence of surgical site infections are needed to fully elucidate differences between CD and PI antiseptics prior to TECABO.

Accuracy of needle arthroscopy for the diagnosis of medial meniscal tears in dogs with cranial cruciate ligament rupture

OBJECTIVE

To determine the accuracy of needle arthroscopy (NA) for the diagnosis of medial meniscal tears in dogs with cranial cruciate ligament rupture (CCLR).

STUDY DESIGN

Prospective clinical trial.

ANIMALS

Twenty-six client-owned dogs.

METHODS

Dogs with CCLR and scheduled to undergo tibial plateau leveling osteotomy were recruited for the study. Needle arthroscopy was performed by an experienced surgeon; the same dog subsequently underwent standard arthroscopy (SA) by another experienced surgeon who was blinded to the NA findings. The SA arthroscopy findings were used as the gold standard. Arthroscopy time, visibility of the menisci, ability to probe the menisci, and the presence of meniscal tears were recorded for both arthroscopies. The degree of lameness before and after NA was subjectively quantified.

RESULTS

The sensitivity and specificity to diagnose medial meniscal tears with NA was 95% and 100%, respectively. Visibility of the menisci was lower (P < .01), probing of the lateral meniscus was harder (P = .0017), and procedure time was shorter (P = .073) with NA when compared to SA. The lameness scores did not differ before and after NA (P = .25).

CONCLUSION

Needle arthroscopy could be performed rapidly with low morbidity, and had high accuracy for detecting medial meniscal tears in dogs with CCLR.

CLINICAL SIGNIFICANCE

Needle arthroscopy is a promising minimally invasive technique for diagnosing medial meniscal tears in dogs with CCLR.

Use of a circular fixator construct to facilitate closed reduction and percutaneous stabilization of a distal femoral physeal fracture in a dog

Background:

Fractures of the distal femoral physis are the most common physeal fracture sustained by skeletally immature dogs. Reduction and stabilization of these fractures can sometimes be achieved through closed reduction, primarily in fractures that are nominally displaced. Circular external fixator constructs have been used to assist in indirect, closed reduction of fractures at other anatomic locations in dogs and this report describes application of this method to reduce a displaced Salter-Harris type II fracture of the distal femur in a 1-year-old dog.

Case Description:

A 1-year-old female spayed Akita was referred for treatment of a Salter-Harris type II fracture of the right distal femur. The epiphyseal segment was laterally and slightly caudally displaced. Multiple attempts to manually reduce the fracture during surgery were unsuccessful, so a two-ring circular external fixator construct was applied to facilitate distraction and reduction. The construct was applied by placing a medial-to-lateral Kirschner wire in both the mid-femoral diaphysis and in the distal femoral epiphysis. Distraction of the construct provided sufficient separation of the fracture segments to facilitate near anatomic reduction. The fracture was stabilized with two percutaneously placed Steinmann pins placed in Rush fashion. Radiographic union was confirmed 5 weeks after surgery. The dog was not lame and was bearing more weight on the right pelvic limb, as assessed using force plate analysis, 9 months following surgery. Goniometric measurements of stifle range of motion and thigh muscle circumference were similar between the pelvic limbs.

Conclusion:

Application of a two-ring circular construct would appear to be useful to facilitate closed reduction and percutaneous stabilization of distal femoral physeal fractures.

Diminished responsivity on a passive avoidance task to second administration of scopolamine

Rats were given two training sessions, separated by intervals of 1, 3, or 6 days, on a passive avoidance task. For each training interval, control groups receiving saline and experimental groups receiving scopolamine prior to both sessions were run. Although scopolamine impaired acquisition of the task, the drugged groups displayed a marked improvement in performance on the second day of training. The data suggest, however, that the degree of behavioral improvement for the scopolamine groups diminished with intervals of increased duration interposed between the 2 training days. Two alternative explanations are entertained to account for the excellent Day-2 performance of the scopolamine groups: the development of a partial physiological tolerance to the effects of scopolamine or the development of a behavioral tolerance, unrelated to any known physiological tolerance.