In vitro assessment of bacterial translocation during needle insertion through inoculated culture media as a model of arthrocentesis through cellulitic tissue

[Sterile puncture of large joints]

OBJECTIVE

Puncture of large joints is performed for diagnostic purposes on the one hand and for the treatment of joint pathologies on the other. Puncture can be used for rapid pain relief by relieving effusions or intra-articular hematomas. The obtained puncture specimen allows immediate visual assessment and subsequent microscopic-cytological and microbiological evaluation in the laboratory.

INDICATIONS

The indication for puncture of a large joint is for diagnosis and/or therapy of inflammatory, traumatic or postoperative joint problems. Diagnostic punctures are used to obtain punctate, to differentiate the location of pain or (rarely) to apply contrast medium for magnetic resonance arthrography. Therapeutic punctures allow the injection of drugs or platelet-rich plasma (PRP) as well as the relief or drainage of effusions.

CONTRAINDICATIONS

If there are inflammatory skin alterations-especially purulent inflammation-joint punctures through these lesions are absolutely contraindicated. Special attention is necessary if the patients are on anticoagulants.

SURGICAL TECHNIQUE

Absolute sterile handling is mandatory. Unnecessary pain can be avoided by a sterile skin wheal of local anesthesia, safe puncture points, and careful handling of the cannulas.

POSTOPERATIVE MANAGEMENT

Joint aspiration material has to be handled according to the local, intrahospital rules in a timely manner. Puncture sites are covered with sterile dressings, and if intra-articular medication is administered, the joints have to be passively moved through the range of motion to distribute the medication. Thereafter, compression therapy from distally to proximally while also covering the puncture site avoids recurrence of swelling or hematoma.

FACTS

If sterile conditions are guaranteed, infections rarely occur (0.04-0.08%, 4-8/10,000 cases). The risk of false-positive detection of microorganisms is extremely low.

Influence of clipping on bacterial contamination of canine arthrocentesis sites before and after skin preparation

OBJECTIVE

To determine the influence of hair removal as part of the aseptic skin preparation of canine arthrocentesis sites and to characterize the bacterial flora remaining after aseptic skin preparation.

STUDY DESIGN

Randomized controlled trial.

STUDY POPULATION

Thirteen shorthaired beagle-cross dogs.

METHODS

A coin toss was used to randomly determine to have one carpus, elbow, tarsus, and stifle clipped. The contralateral side was left unclipped. Aseptic skin preparation was performed on all sites with 4% chlorhexidine followed by 70% isopropyl alcohol. The skin of each site was sampled for aerobic and anaerobic bacterial cultures before and after aseptic skin preparation. Bacterial cultures were submitted for laboratory testing to determine the colony-forming units (CFU) of bacteria and bacterial species isolated for each site.

RESULTS

Each group (clipped and unclipped) included 52 sites. Aseptic skin preparation reduced bacterial CFU in both groups. There was no association between values for CFU per milliliter after skin preparation of dogs and side (P = .07), joint (P = .71), pre-aseptic skin preparation CFU (P = .94), or clipping (P = .42). Staphylococcus spp were the most common of the bacterial species cultured.

CONCLUSION

In clean shorthaired dogs without visible evidence of dermatological disease, leaving arthrocentesis sites unclipped rather than performing traditional surgical clipping did not result in increased bacterial skin counts after aseptic skin preparation.

CLINICAL SIGNIFICANCE

In this study we did not find evidence to support that clipping of canine arthrocentesis sites is required for effective aseptic skin preparation. A prospective clinical trial is required to determine whether a change in practice would be associated with increased morbidity.