DR MANKAR DR FAIZAN

Antibiotic

Contents

IntroductionAims & ObjectivesReview of LiteratureComponents of study

Contents

Trial DesignObservationsEvaluation & ResultsInferencesReferences

IntroductionIntroduction

Infection is one of the dreadest Infection is one of the dreadest complication in orthopaedics.complication in orthopaedics.

So the strive has always been there to So the strive has always been there to prevent and control it.prevent and control it.

Hence this study, exploring this option for Hence this study, exploring this option for control of infectioncontrol of infection

Aim of studyAim of study

Assessment of control of Assessment of control of infection after use of infection after use of cement-antibiotic beads/ cement-antibiotic beads/ nailnail

Objective of studyObjective of study

To find out time required for complete To find out time required for complete actionaction

Cost benefit ratio for patientCost benefit ratio for patient To find out antibiotics which can be usedTo find out antibiotics which can be used To study complications involved in the To study complications involved in the

procedureprocedure To make suitable recommendations based To make suitable recommendations based

on the studyon the study

REVIEW OF LITERATURE

The story of modern cements began with Otto Röhm’s invention in the early 20th century of polymethyl methacrylate (PMMA), a solid material with good biocompatibility.

In the 1960s Sir John Charnley began using bone cement on numerous patients for the fixation of both the femur and acetabulum. Before the end of the decade, Buchholz came up with the idea of adding an antibiotic to the cement to decrease the incidence of infection.

Processing times of bone cement Polymerization depends on

a.Room temperature b.Temperature of the bone cement components c.Prothesis temperature

1. Mixing phase Complete wetting of the powder with liquid ! This produces a homogeneous cement Hand mixing: Risk of air bubbles in the paste

2. Waiting phase Swelling of the paste material Slow polymerisation Increased viscosity, but paste still sticky

3. Working phase completion of the waiting phase essential!(ideal working

viscosity) application into the femur(for manual application non-

sticky,viscosity not too high))

4.Hardening phase Strength of the cement increases Polymerisation comes to a halt Duration of poşymerisation dependent on

.Room temperature,

.Component temperature,

.Prothesis temperature

.Air humidity

During polymerization, cement properties critical for operating procedures, such as viscosity change, setting time, cement temperature, mechanical strength, shrinkage and residual monomer, are determined. These properties will influence cement handling, penetration and interaction with the prosthesis.

Properties

Temperature affects mixing time, delivery of the cement, prosthesis insertion, and other aspects of the cementing process. It is therefore very important to control the temperature of the bone cement and the OR.

To achieve optimal cement properties, it is important to adhere to the time schedules indicating the correlation of temperature to handling time. These time schedules are usually included in the instructions for the bone cement.

High viscosity cements are sometimes pre-chilled for use with mixing systems for easier mixing and prolonged working phase. This will also increase the setting time. The relative humidity might also influence the handling properties. That is the reason why the the working time and setting time of the cement might vary in winter and summer.

Temperatures

Antibiotic-loaded bone cement

Infection is the most feared complication in orthopaedics. The infection usually leads to a complete failure of any orthopaedic surgery, resulting in a long series of operative procedures, great discomfort for the patient and heavy costs.

Infections occur because of the high affinity of many germs to the surface of implants. Once settled, germs are less sensitive to antibiotics, as they are covered with a “slime” preventing them from attacks from the host defence mechanism. This renders treatment with systemic antibiotics ineffective

A solution to the problem is preventing the settlement of germs. The use of antibiotic-loaded bone cements allows for high local concentrations of antibiotics to be administered to the areas surrounding the implant, protecting the implant from the settling of germs. Moreover, antibiotic levels in the serum are sufficiently low so as to avoid causing side effects.

The addition of antibiotics to bone cement was undertaken at the beginning of the 1970s by Buchholz, from Hamburg. His idea was to add antibiotics to the cement in order to reduce the incidence of infection, which was high at that time. Using gentamicin or vancomycin in combination with PMMA cement, it was found that the combination was stable and offered a suitable spectrum of antibiotic activity.

Attention must be given to reducing the incidence of infection in surgery and to fighting infection once it has occurred.

Orthopaedic infections There are numerous reports in the literature about the

incidence of postoperative wound sepsis and the organisms causing this complication. Almost 75% of all bacteria that can be isolated during hip operations are Gram-positive, with staphylococci representing the majority. Among Gram-negative bacteria, E. coli and pseudomonas are most common.3

Antibiotic therapy, although usually not adequate alone, is a critical element in the treatment of infected surgery. Consultation with an infectious disease specialist can help the surgeon select the appropriate antibiotic, determine the duration of therapy, and evaluate the response to the treatment

Antibiotic-loaded bone cement

Gentamicin and Vancomycin are aminoglycoside antibiotics . They are bactericidal, has a dose-dependent killing curve, remains stable when exposed to heat and are soluble in water. These four characteristics make them especially suited for use in bone cement.

The substance is slowly eluted in the surrounding tissue

Trial designTrial design

Inclusion/ Exclusion criteriaInclusion/ Exclusion criteria All age and sex includedAll age and sex included All orthopaedic infections of extremities All orthopaedic infections of extremities

includedincluded Non infected cases, infections of trunk and Non infected cases, infections of trunk and

spine and head/ neck excludedspine and head/ neck excluded

Materials and MethodsMaterials and Methods

Pts will be admitted and investigated forPts will be admitted and investigated for X RaysX Rays Pus culture and sensitivity if possiblePus culture and sensitivity if possible Blood investigations( TLC, DLC, ESR, Blood investigations( TLC, DLC, ESR,

BSL)BSL) After fitness surgical debridement and After fitness surgical debridement and

application of antibiotic impregnated application of antibiotic impregnated cement beads/ nail (whichever applicable)cement beads/ nail (whichever applicable)

Post op X rays and continue with Post op X rays and continue with dressings till wound healsdressings till wound heals

Note time taken for control of infection, Note time taken for control of infection, functional outcome, patient satisfactionfunctional outcome, patient satisfaction

Case record forms, patient information Case record forms, patient information sheet, and consent formssheet, and consent forms

ResultsResults

Our study in the phase of data collectionOur study in the phase of data collection Few examples from our study Few examples from our study

Pus pouring

These nails and beads need removal once These nails and beads need removal once the infection is controlled usually after 2 the infection is controlled usually after 2 months of insertion- this is the only months of insertion- this is the only disadvantage of requirement of one more disadvantage of requirement of one more surgery for removalsurgery for removal

But this procedure definitely also avoids But this procedure definitely also avoids many surgeries to the patient which he many surgeries to the patient which he might have needed for control of infection might have needed for control of infection and wound cover like what we have seen. and wound cover like what we have seen.

Thanks!! Thanks!!