Complications in Canine Cranial Cruciate Ligament Surgery. Ron Ben-Amotz

Complications in Canine Cranial Cruciate Ligament Surgery - Ron Ben-Amotz


Скачать книгу
identified from an aseptically collected sampleIncision is reopened with purpose and organisms are identified from an aseptically collected sample AND the patient exhibits localized swelling, pain, erythema, or heatDiagnosed as an SSI by a physician Deep SSI MUST:Occur within 30 days (no implant) or 90 days (implant)Involves tissues deep to the subcutaneous tissuesMust have AT LEAST one of the following:Purulent discharge from the incisionIncision spontaneously dehisces or is reopened with purpose AND organisms are identified from an aseptically collected sample AND the patient exhibits localized pain or pyrexiaLocal abscess formation Organ/space MUST:Occur within 30 days (no implant) or 90 days (implant)Involves any tissues deep to the fascia/muscle that was opened during surgeryMust have AT LEAST one of the following:Purulent discharge from a drain within the organ/spaceOrganisms are identified from an aseptically collected sample from fluid or tissue within the organ/spaceLocal abscess formation

      The vast majority of SSIs occur secondary to contamination of the surgical site by commensal or pathogenic organisms arising from the patient's own microbiome [8]. The most common microorganism identified in SSIs is Staphylococcus pseudintermedius. Other common microorganisms identified include Streptococcus spp., Pseudomonas aeruginosa, and Escherichia coli. Staphylococcus pseudintermedius is an opportunistic pathogen with an ability to create a biofilm, leading to its increased virulence [9]. The ability to create a biofilm is important as it makes eradication of these SSIs more challenging. Additionally, resistance of S. pseudintermedius is on the rise, creating an even greater challenge for management of patients with SSIs [9].

      Following the diagnosis of a SSI, several factors must be considered prior to determining a treatment protocol. These include the patient's overall clinical status, category of SSI (superficial, deep, organ/space), susceptibility of inciting microorganisms, presence of biofilm formation, stage of healing, availability of treatment options, and client considerations such as emotional and financial strain associated with treatment.

      The vast majority of SSIs reported by category in the veterinary literature are limited to superficial or deep tissue layers, with an organ/space SSI occurring in <1% of infections [4, 10].

      Regardless of the potential for resistance, response to topical therapy should be monitored and treatments altered if there is a lack of response. Ideally, a bacterial culture should be submitted from the onset of clinical signs, so that an appropriate systemic antimicrobial can be added to the treatment regime, should topical therapy fail to resolve the SSI.

      Systemic antimicrobial therapies should be employed in the face of an intact incision and direct identification of microorganisms. Initially, systemic antimicrobials will be chosen empirically until the results of culture and susceptibility testing are available to guide specific therapy. It is important to collect and submit a bacterial culture when an SSI is suspected, to ensure appropriate antimicrobial stewardship is followed and reduce the risk of potentiating antimicrobial resistance.

      Initial empirical recommendations will vary based on hospital known infectious agents and their resistance patterns. Appropriate duration of therapy is a topic of debate and varies between prescribers, with reported treatment lengths ranging from 1 to 6 weeks of antimicrobial therapy [12, 13]. While extended durations of antimicrobial therapy are reported, these prolonged courses of antimicrobials are not likely required unless implanted materials are involved. Most uncomplicated, superficial SSIs will resolve with a systemic course of antimicrobials for 3–5 days. Ultimately, when antimicrobial therapy is discontinued and there is recurrence of clinical signs, involvement of implanted materials should be considered and prolonged antimicrobial therapy based on culture and susceptibility results will be required until implanted materials can be removed or local therapies can be employed [12].

Photo depicts scanning electron microscopy image of a biofilm.

      Source: Adapted from Singh et al. [9].

      Additional approaches to biofilm infections are currently limited. Two enzymes have been identified as being able to prevent biofilm formation; deoxyribonuclease I and dispersin B. While both are capable of inhibiting biofilm formation, only dispersin B has been proven to be able to disrupt an established biofilm [24]. A recent in vitro study has identified that the combination of dispersin B and amikacin in a biodegradable gel allows for rapid elution of dispersin B with a gradual reduction in concentrations over a period of 10 days [25]. While this is a promising avenue, clinical application has not yet been assessed.


Скачать книгу