Brazilian Journal of Anesthesiology
https://bjan-sba.org/article/doi/10.1016/j.bjane.2013.08.004
Brazilian Journal of Anesthesiology
Scientific Article

In vitro comparison of epidural bacteria filters permeability and screening scanning electron microscopy

Comparação in vitro da permeabilidade de filtros epidurais antibacterianos e triagem por microscopia eletrônica de varredura

Aysin Sener; Yuksel Erkin; Alper Sener; Aydin Tasdogen; Esra Dokumaci; Zahide Elar

Downloads: 0
Views: 689

Abstract

BACKGROUND AND OBJECTIVES: Epidural catheter bacteria filters are barriers in the patient-controlled analgesia/anaesthesia for preventing contamination at the epidural insertion site. The efficiency of these filters varies according to pore sizes and materials. METHOD: The bacterial adhesion capability of the two filters was measured in vitro experiment. Adhesion capacities for standard Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATCC 27853) strains of the two different filters (Portex and Rusch) which have the same pore size were examined. Bacterial suspension of 0.5 Mc Farland was placed in the patient-controlled analgesia pump, was filtered at a speed of 5 mL/h. in continuous infusion for 48 h and accumulated in bottle. The two filters were compared with colony counts of bacteria in the filters and bottles. At the same time, the filters and adhered bacteria were monitored by scanning electron microscope. RESULTS: Electron microscopic examination of filters showed that the Portex filter had a granular and the Rusch filter fibrillary structure. Colony counting from the catheter and bottle showed that both of the filters have significant bacterial adhesion capability (p < 0.001). After the bacteria suspension infusion, colony countings showed that the Portex filter was more efficient (p < 0.001). There was not any difference between S. aureus and P. aeruginosa bacteria adhesion. In the SEM monitoring after the infusion, it was physically shown that the bacteria were adhered efficiently by both of the filters. CONCLUSION: The granular structured filter was found statistically and significantly more successful than the fibrial. Although the pore sizes of the filters were same - of which structural differences shown by SEM were the same - it would not be right to attribute the changes in the efficiencies to only structural differences. Using microbiological and physical proofs with regard to efficiency at the same time has been another important aspect of this experiment.

Keywords

Bacteria filter, Staphylococcus aureus, Pseudomonas aeruginosa, Scanning electron microscope

Resumo

JUSTIFICATIVA E OBJETIVOS: Os filtros antibacterianos para cateter epidural são barreiras da analgesia/anestesia controlada pelo paciente para evitar a contaminação do local de inserção epidural. A eficácia desses filtros varia de acordo com o material e o tamanho dos poros. MÉTODO: A capacidade de aderência bacteriana dos dois filtros foi medida em experimento in vitro. Avaliamos a capacidade de aderência das cepas padrão de Staphylococcus aureus (ATCC 25923) e Pseudomonas aeruginosa (ATCC 27853) de dois filtros diferentes (Portex e Rusch), mas com poros do mesmo tamanho. Uma suspensão bacteriana grau 0,5 de McFarland foi colocada na bomba de analgesia controlada pelo paciente e filtrada a uma velocidade de 5 mL/h em infusão contínua por 48 horas e acumulada em frasco. Os dois filtros foram comparados com contagens de colônias de bactérias nos filtros e frascos. Ao mesmo tempo, os filtros e as bactérias aderidas foram monitorados com microscópio eletrônico de varredura. RESULTADOS: O exame dos filtros por microscópico eletrônico mostrou que a estrutura do filtro Portex era granulada e a do filtro Rusch fibrilar. A contagem de colônias do cateter e do frasco mostrou que ambos os filtros tinham uma capacidade de adesão bacteriana significativa (p < 0,001). Após a infusão da suspensão bacteriana, as contagens de colônias mostraram que o filtro Portex foi mais eficiente (p < 0,001). Não houve qualquer diferença entre as adesões de bactérias S. aureus e P. aeruginosa. Na monitoração por MEV após a infusão, ficou fisicamente evidente que as bactérias foram aderidas de modo eficaz por ambos os filtros. CONCLUSÃO: O filtro com estrutura granular foi estatística e significativamente mais bem- sucedido do que o filtro com estrutura fibrilar. Embora o tamanho dos poros dos filtros fosse igual - as diferenças estruturais mostradas pelo MEV eram semelhantes -, não seria justo atribuir as alterações de eficiência apenas às diferenças estruturais. O uso ao mesmo tempo de provas microbiológicas e físicas para avaliar a eficácia foi outro aspecto importante deste experimento.

Palavras-chave

Filtro antibacteriano, Staphylococcus aureus, Pseudomonas aeruginosa, Microscópio eletrônico de varredura

References

Wallace M, Yaksh TL. Long-term spinal analgesic delivery: a review of preclinic and clinical literature. Regional Anaesth Pain Med.. 2000;25:117-57.

De Cicco M, Matovic M, Castellani GT. Time-dependent efficacy of bacterial filters and infection risk in long-term epidu- ral catheterization. Anesthesiology.. 1995;82:765-71.

Kehlet H, Holte K. Effect of postoperative analgesia on surgical outcome. Br J Anaesth.. 2001;87:62-7.

Low SHJ. Survey of epidural analgesia management in general intensive care units in England. Acta Anaesthesiol Scand.. 2002;46:799-805.

Wood CE, Goresky GV, Klassen KA, Kuwahara B, Neil SG. Complications of continuous epidural infusions for post- operative analgesia in children. Can J Anaesth.. 1994;41(7):613-20.

Du Pen. Complications of neuraxial infusion in cancer patients. S. Oncology (Williston Park).. 1999;13(5 Suppl 2):45-51.

Grewal S, Hocking G, Wildsmith JA. Epidural abscesses. Br J Anaesth.. 2006;96(3):292-302.

Kindler CH, Seeberger MD, Staender SE. Epidural abscess complicating epidural anesthesia and analgesia. An analysis of the literature. Acta Anaesthesiol Scand.. 1998;42(6):614-20.

Hayek MS, Paige B, Girgis G. Tunneled epidural catheter infections in noncancer pain: increased risk in patients with neuropathic pain/complex regional pain syndrome. Clin J Pain.. 2006;22(1):82-9.

Peuges DA, Carr DB, Hopkins CC. Infectious complications asso- ciated with temporary epidural catheters. Clin Infect Dis.. 1994;19:970-2.

Byres K, Axelrod P, Michael S. Infections complicating tun- neled intraspinal catheter systems used to treat chronic pain. Clin Infect Dis.. 1995;21:403-8.

Abouleish E, Amortegui AJ. Correspondence: milipore fil- ters are not necessary for epidural block. Anesthesiology.. 1981;55(5):604.

Abouleish E, Amortegui AJ, Taylor FH. Are bacterial filters needed in continuous epidural analgesia for obstetrics. Anes- thesiology.. 1977;46(5):351-4.

Smitt PS, Tsafka A, Teng Van-de Zande F. Outcome and complications of epidural analgesia in patients with cancer pain. Cancer.. 1998;83:2015-22.

Kaushal M, Narayan S, Aggarwal R. In vitro use of bacterial filters for prevention of infection. Indian Pediatr.. 2004;41:1133-7.

Du pen SL, Peterson DG, Williams A, Bogosian AJ. Infection dur- ing chronic epidural catheterization: diagnosis and treatment. Anesthesiology.. 1990;73:905-9.

Phillips JM, Stedeford JC, Hartsilver E, Roberts C. Epidu- ral abscess complicating insertion of epidural catheters. Br J Anaesth.. 2002;89(5):778-82.

Simpson RS, Macintyre PE, Shaw D. Epidural catheter tip cultures: results of a 4-year audit and implications for clinical practice. Reg Anesth Pain Med.. 2000;25(4):360-7.

Wang LP, Hauerberg J, Schmidt JF. Incidence of spinal epidu- ral abscess after epidural analgesia: a national 1-year survey. Anesthesiology.. 1999;91:1928-36.

5dcd9f6e0e8825c46dbf58f1 rba Articles
Links & Downloads

Braz J Anesthesiol

Share this page
Page Sections