Urinary catheters - a matter of convenience? Aniruddha Chakravarti Consultant Urological Surgeon

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1 Urinary catheters - a matter of convenience? Aniruddha Chakravarti Consultant Urological Surgeon

2 Indications Any absolute? Relative Retention - ISC vs IDC? Incontinence - containment devices/drugs/nursing vs IDC Immobility - care and assistance vs IDC Most compelling Community dwelling elderly with severe dementia - nursing home Neurogenic

3 IDC - at what cost? Encrustation Recurrent blockage Failed catheter changes and urethral injuries UTI Sepsis Renal failure Increased emergency admissions Increased hospital stay

4 Quality of life? a toll on the health service?? Up to 50% of the patients undergoing long-term catheterization will experience catheter encrustation and blockage. An insight into the prevalence of the complication was given by the observations of Kohler-Ockmore and Feneley. They followed 457 long-term catheterized patients in community care in the Bristol area over a 6-month period and recorded 506 emergency referrals, mostly to deal with catheter blockage. The problem thus puts the health of many patients at risk and makes substantial demands on the resources of a health service.

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6 What is a biofilm Biofilms are complex communities of surfaceattached microorganisms, comprised either of a single or multiple species Bacteria in most environments are not found in a unicellular, planktonic (free-living) form such as those typically studied in the laboratory, but exist predominantly in multi-cellular surface attached communities called biofilms (Costerton et al., 1995).

7 How do biofilms form?

8 Bacteria in biofilms Bacteria within the biofilm are phenotypically different from their planktonic counterparts. Antimicrobial agents would therefore frequently fail to eradicate them. Bacteria within a biofilm activate many genes, which change their surfaces and other molecular targets, reducing the susceptibility to antimicrobial agents (intrinsic resistance).

9 Catheter biofilms Proteus mirabilis is most commonly isolated from the urine of patients suffering from recurrent catheter encrustation and blockage. It is also the species most commonly recovered from patient s encrusted catheters. The urease of P. mirabilis is a potent enzyme, being able to hydrolyze urea several times faster than those produced by other species.

10 Proteus mirabilis It was named Proteus after an elusive character in Homer s Odyssey who escaped capture by changing form. Its natural habitat is the intestinal tract where it forms part of the faecal flora. In individuals with normally functioning urinary tracts, it rarely causes infection. In patients whose urinary tracts are subjected to chronic inflammatory changes from procedures such as long-term catheterization, however, it becomes a significant pathogen.

11 Proteus mirabilis a very sticky bacillus four different adhesins that mediate its attachment to tissue and catheter surfaces. An exopolysaccharide capsule protects it against host s defences secretes substances essential for extracting important nutrients from host tissues and fluids. produces a specific IgA protease that is capable of degrading the predominant immunoglobulin in the mucus secreted from epithelial surfaces. Finally, it has two signature features that are particularly important in the catheterized urinary tract. Along with its

12 A spectacular bacteria!! When they attach to a surface spectacular changes can occur that transform them into cells that can be up to 80 mm long. These elongated cells can produce hundreds of flagella per cell and organize themselves into parallel groups tied together by the helical binding of the flagella around adjacent cells These rafts of cells are then capable of moving off rapidly in a co-ordinated manner (swarming) over solid surfaces. In this way they can spread over surfaces and colonize new locations.can swarm rapidly over all-silicone, silicone- coated latex, hydrogel-coated latex and hydrogel/silver- coated latex catheters

13 Encrustation Urea splitting bacteria colonise Formation of biofilm communities embedded in a polysaccharide matrix. Enzymatic hydrolysis of urea - ph Become trapped in organic matrix Calcium and magnesium salts crystallize out Alkali induced gel stabilization

14 Biofilms Electron micrograph picture of external and internal surface of Stent showing early biofilms

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16 Effects of biofilm and encrustation The crystalline deposits hard and abrasive traumatise the bladder mucosa and urethra. Obstruction of urinary flow incontinence due to leakage of urine around the catheter urinary retention. Bacteriuria is always found in these patients - retention and vesico-ureteral reflux may facilitate ascending infection of the urinary tract pyelonephritis, septicaemia and shock [29,30]. undetected catheter blockage may lead to life-threatening complications. up to 50% of patients undergoing long-term catheterisation will require unscheduled catheter replacement

17 Modification of biomaterial surface most promising prevention strategy for bacterial biofilms. controlled release of antimicrobial agents or antiseptics (minocycline, rifampicin, gentamicin, nitrofurantoin) incorporated in the device material surface coatings with silver and other metals surface modifications to change or increase hydrophobicity create functional groups with intrinsic antimicrobial activity, and anti-adhesive surfaces such as heparin

18 nanotechnology in medicine resulted in a new field called nanomedicine Nanomaterial development is now viewed as a promise strategy for controlling or treating pathogenic biofilms on indwelling medical devices and implants

19 Nanoparticles Most of the nanoparticles examined have been metals, metal oxides, polymers, metal-based polymeric composites, peptides, or combinations of these liposomes, antibiotic encapsulated nanoparticles, responsive smart nanomaterials that have antimicrobial effects but cause minimal damage to the host. Drug loaded nanoparticles could overcome the limitations of conventional antibiotic treatments associated with toxicity near-infra red light (NIR) alternating magnetic fields (AMFs)

20 Electrified catheter

21 new device Preventing microbial biofilms on catheter tubes using ultrasonic guided waves

22 Future New biomaterials Collaboration of material engineering and microbiology Nanoparticles - nano medicine 3D printing

23 Until then Indwelling long term urinary catheter should be the last resort Have all other options been considered? is there adequate care and support available? Regular culture of catheter urine to identify BLOCKERS

24 Project - Catheter Safety (PCS) Aim Reduce community unplanned catheterisations and urinary catheter associated bacteraemia (UCAB) Objectives Standardise LTUC equipment in Wolverhampton Review patients with LTUC in Wolverhampton Reason for catheter Possible removal/alternative Correct prescription Food & fluid Bowels UTI and catheter problems Provide a plan and review process for all considered at high risk of bacteraemia ( 2 catheter changes in 3 months)

25 Indication for catheter? Other breakdown Other 126 Immobility 2 Incontinence 11 Comfort care/hospice Care 6 Input and output monitoring 3 Neurogenic 55 Decubitus ulcer 1 Urologic surgery 3 Urinary Obstruction, 460 Not known 60 Gross Haematuria

26 Project Catheter safety Outcomes 2 catheter changes/3 mnt 37% 716 catheterised patients assessed in 5 months, 191 of catheters were removed <2 catheter changes/3 mnt 63%

27 PCS outcomes Preferred list launched to GP s and on formulary Assessed patients have documented reason for catheter Assessment information to be placed on portal Assessed patients moved to all silicone catheter from preferred list Patient held catheter record trialled in 3 nursing homes Patient specific plans and monitoring in one DN locality Business case commenced for catheter referral Improved engagement with DN s.

28 PCS - challenges and next steps Challenges Coding of district nursing activity Identifying reason for catheter (CH/GP/EPR/Patient /NOK ) Constant flow of discharged patients Poor documentation in care homes Liaison between multiple health care professionals. Next steps Sustainability (commissioning conversations) Catheter review/twoc clinics Number of unplanned catheter changes compared to pre-project Acute area actions to reduce catheter use identify is there is an effect gramnegative bacteraemia

29 Caution! Before deciding on a long term indwelling urinary catheter 1 in 2 chances of ED attendance 1 in 3 chances of recurrent blockage and life threatening condition Quality of life and impact on resources