Vesna NOVAK-JANKOVIČ

English

Hrčak - Portal of scientific journals of Croatia

Infectious complications of regional anaesthesiaand analgesiaINTRODUCTIONRegional anaesthetic techniques provide excellent anaesthesia andanalgesia for many surgical procedures. Regional anaesthesia isgained increased popularity all over the world. Regional anaesthesia isassociated with many benefits compared to general anaesthesia, includ-ing reduced morbidity and mortality, superior postoperative analgesiaand reduced costs (1). However, neurological injury after regional an-aesthesia can be distressing to the patients and their families. Mostcomplications of regional anaesthesia are relatively minor, easily man-aged and temporary but in rare cases serious and permanent damagecan occur. Neurologic complications associated with central neuraxialblock (CNB) can be attributed to incorrect placement of a needle orcatheter causing direct neural tissue damage, toxic and infectiousagents, and spinal cord compromise resulting from ischemia or masseffect (2).Infectious complicationsInfectious complications may occur with any regional anaesthetictechnique. However those associated with the neuraxial anaesthesiaand analgesia may result in devastating morbidity and mortality, in-cluding abscess formation, necrotizing fasciitis, meningitis, arachnoi-ditis, paralysis and death. The risks of serious central or peripheral ner-vous system infection are low, and with strict adherence to sterilityduring the block performance there is little probability of infection be-ing introduced. However, recent epidemiologic studies suggest theenormous discrepancy of infectious complications associated with neu-raxial techniques. The rate of spinal-epidural abscess or meningitisoccurence has been reported to be 1:10 000 to 1:40 000 (3, 4, 5). Aromaaet al. reported lower infectious complication rate of 1.1:100 000 blocks(6). On the contrary Wang et al. estimated that the incidence of epiduralabscess after epidural analgesia was 1:1930 and the risk of permanentneurologic deficit was 1:4343 catheters (7). This discrepancy can be ex-plained by different data collection techniques, differences in postoper-ative monitoring and reporting and in aseptic technique and antibioticadministration,varying definitions of infection and colonization. Thefrequency of infection associated with peripheral neural catheters re-mains undefined. Capdevila et al. showed that 29% of peripheral nervecatheters may become colonized with 3% resulting in localized inflam-mation (8).VESNA NOVAK-JANKOVI^Cinical Department of Anaesthesiology andIntensive Therapy, University Medical CentreLjubljana, SloveniaE-mail: vnjankovic@hotmail.comReceived March 16, 2011.PERIODICUM BIOLOGORUM UDC 57:61VOL. 113, No 2, 247–250, 2011 CODEN PDBIADISSN 0031-5362Education/new procedureRoutes of infectionThe etiology of infectious complications is often un-clear. Potential routes might be contaminated syringes,catheter hubs, local anaesthetics or breaches in aseptictechnique. Dural puncture has long been considered arisk factor in the pathogenesis of meningitis. The sug-gested mechanisms include introduction of blood intothe intrathecal space during needle placement and dis-ruption of the protection provided by the blood-brainbarrier.Skin bacteria gain epidural space through the catheterinsertion site. This is supported by Saguraki et al. whotraced the source of an epidural abscess to Staphylococ-cus aureus strains fom the patient’s skin flora (9).Kindler et al. revealed that 83% of 35 epidural catheterrelated infections, were caused by various Staphylococ-cus species, typical for bacterial flora of the skin (10). Themost frequently detected microorganism on the skin sur-face is S. epidermidis (65–69% of skin flora), while S.aureus (1–2% of skin flora) is the most prevalent micro-organism in epidural infections. This suggests that S.aureus may be more resistant to disinfectants than othermicroorganisms (11). Important components of aseptictechnique are summarized in Table 1. (12). However,most epidural abscesses are not related to the placementof indwelling catheters but are believed to be related toinfections of the skin, soft tissue, spine or haemato-genous spread to the epidural space.Risk factorsPossible risk factors include underlying sepsis, diabe-tes, depressed immune status, steroid therapy, localizedinfection and chronic catheter maintenance (13). Pa-tients with altered immune status because of neoplasm,immunosuppression after solid organ transplantation andchronic infection with human immunodeficiency virusor herpes simplex virus are often not considered candi-dates for neuraxial blocks. These patients are susceptibleto infection with opportunistic pathogens. Anaesthesiol-ogists have long considered sepsis to be a relative contra-indication to the administration of spinal or epidural an-aesthesia. However, if there is a clear benefit to be gainedfrom epidural anaesthesia or analgesia, a septic condi-tion is not an absolute contraindication (14). Postulatedmechanisms for haematogenous infection of the centralnervous system caused by subarachnoid or epidural pun-cture might be an accidental vessel puncture. Antibioticchemoprophylaxis should be given before the punctureand the patients must be closely followed for the develop-ment of epidural abscess. Because of the possibly in-creased risk of infectious complications, informed con-sent should be obtained from the patient (15). The deci-sion to perform a regional anaesthetic technique must bemade on an individual basis considering the benefits ofregional anaesthesia and the risk of central nervous sys-tem infection which may occur in any bacteremic pa-tient. Available data suggest that patients with evidenceof systemic infection may safely undergo spinal anaes-thesia, provided appropriate antibiotic therapy. Meningi-tis and epidural abscess are both complications of neu-raxial blocks, the risk factors and causative organisms aredisparate. Staphylococcus is the organism most com-monly associated epidural abscess and often this infec-tions occured in patients with impaired immunity. Men-ingitis follows dural puncture is typically caused by alpha--hemolytic streptococci, with the source of the organismthe nasopharynx of the anaesthesiologist (16).To date, there are published three serious infectiouscomplications of peripheral block. Two of the three oc-curred in immunocompromised patients (17). A case offatal necrotizing fasciitis after single-injection axillaryblock in woman with a history of diabetes mellitus hasbeen published (18).Symptoms, signs and diagnosisThe most frequent signals of an impending epiduralinfectious complication are local tenderness and infec-tious signs at the skin catheter entry site and new back-ache. Subsequently, increasing leg weakness, loss of sen-sation and sphincter control in the presence of backache248 Period biol, Vol 113, No 2, 2011.Vesna Novak-Jankovi~ Infectious complications of regional anaesthesia and analgesiaTABLE 1Important components of aseptic technique.MajorRemoval of watches, jewelryHand washing with antiseptic solutionsSurgical masks, caps, sterile gowns and glovesSkin desinfection, alcohol, chlorhexidineSterile drapingMinorBacterial filtersPrevention of catheter, hub and site violationsTABLE 2Signs and symptoms of the epidural abscess and men-ingitis.Epidural abscess MeningitisAltered mental status andseizures– +Fever +,– +Headache –,+ +Stiff neck –,+ +Photophobia – +Back pain +,– +,–Paraplegia /paraparesis + –Sensory involvement + –Nausea and vomiting – +Incontinence of urin and feces + –are ominous signs (Table 2). Epidural abscess formationusually occurs days to weeks after neural block associ-ated with fever and leukocytosis (Table 3) (13). How-ever, it is important to know that an epidural abscessmay present with paraplegia and no backache or pyre-xial symptoms.Computer tomography can help in verifying the diag-nosis, however CT-scans have given false negative find-ings in up to 50% of cases (19). The most sensitive diag-nostic procedure is MRI with or without gadoliniumcontrast enhancement.Treatment of infectious complicationsAbscess formation after epidural or spinal anaesthesiacan be superficial, requiring limited surgical drainageand intravenous antibiotics, or occur deep in the epiduralspace with associated cord compression. The latter is for-tunately a rare complication, but it requires aggressive,early surgical decompression to achieve a satisfactoryoutcome (13).Antibiotics alone cured some patients who had mini-mal or no neurological symptoms.Case reportWe have published case report about acute bacterialtransverse myelitis, secondary to an epidural catheter. A49-year-old man who underwent left pneumonectomybecause of the lung carcinoma received general and epi-dural (Th6-7) anaesthesia. The operative procedure, an-aesthesia and early postoperative course were unevent-ful. Through an epidural catheter mixture of morphine,bupivacaine and clonidine was administered for two dayspostoperatively. On the fifth postoperative day patientdeveloped progressive paresis in the lower extremities.There was a loss of sensation below seventh thoracicdermatoma. Elevated inflammatory parameters alongwith the results of cerebrospinal fluid analysis and mag-netic resonance imaging were suggestive of acute trans-verse bacterial myelitis of the spinal cord. Despite promptantibiotic therapy, anti-oedema treatment and rehabili-tation, the neurological deficit failed to resolve (20).OutcomeAfter surgical management 45% of the patients whorecovered good or complete spinal cord functions re-ceived antibiotic therapy earlier than those who did notrecover full spinal cord functions (10). Epidural absce-sses are treated too late because of careless postoperativesurveillance by medical and nursing staff, who are un-focussed upon the early symptoms and signs of evolvingspinal cord dysfunction and imminent neurological ca-tastrophes (21).RecommendationsBecause of the catastrophic consequences to the pa-tient, as well to the anaesthesiolgist of such complica-tions, recommendations are important to provide qualitypatient care.Implications of aseptic techniquesThorough handwashing and remove of jewelry re-duce the risk of cross-contamination.Alcohol-based chlorhexidine antiseptic solutions willprovide high degree of antimicrobial activity.Sterile surgical gloves and gowns should be used.The use of surgical masks significantly reduce thecontamination from microorganisms grown in the upperairway of clinicians.Regional anaesthesia in the febrile or infectedpatientSerious central neuraxial infections such as arachnoi-ditis, meningitis and abscess after spinal or epidural an-aesthesia are rare.The decision to perform regional anaesthesia must bemade considering patient’s preoperative status, the bene-fits of regional anaesthesia and the risk of central nervoussystem infections.Epidural catheters should be removed in the presenceof local erythema.Period biol, Vol 113, No 2, 2011. 249Infectious complications of regional anaesthesia and analgesia Vesna Novak-Jankovi~TABLE 3Differential diagnosis of epidural haematoma, epidural abscess and anterior spinal artery syndrome.Epidural abscess Epidural haematoma Syndrome art. spinalis anteriorAge of patient Any age > 50 yr ElderlyHistory Infection Anticoagulants ArteriosclerosisOnset 1–3 days Sudden SuddenGener. symptoms Fever, malaise Back pain NoneParalysis Flaccid Flaccid FlaccidMRI/CT Epid. compression Epid. compression NormalCerebrospinal fluid  Cell count Normal NormalSensory involvement Paresthesias Variable MinorBlood data  leukocytosis Abnorm coagulation NormalA delay in diagnosis and treatment of CNS infectionsmay significantly worsen neurologic outcome.Regional anaesthesia in theimmunecompromised patientThe attenuated inflammatory response within theimmunocompromised patient may diminish the clinicalsigns and symptoms of infections.The risk of epidural abscess increases with the dura-tion of epidural catheterization.Viremia, fever and meningitis in the presence of HSV--type 2 infection suggest a conservative approach.Neuraxial and peripheral techniques can be perfor-med safely in HIV-infected patients (12, 13, 17).CONCLUSIONInfectious complications may occur with any regionalanaesthetic technique but serious central or peripheralnervous system infections are low. Aseptic technique iscritical to minimize the risk of extrinsic contaminationPatients with a bacteraemia or septicaemia may benefitfrom regional anaesthesia but each patient requires care-ful preoperative evaluation and appropriate antibiotictherapy should be instituted before the block. Emphasison close surveillance and monitoring for early signs andsymptoms of infections, as well as high preparedness forearly treatment with surgical decompression and antibi-otics, and recommendations will ensure that infectiouscomplications remain rare occurrences.REFERENCES1. BRULL R, MC CARTNEY C J L, CHAN V W S, EL-BEHEIRY H2007 Neurological complications after regional anesthesia: contem-porary estimated of risk. Anesth Analg 104: 965–742. HORLOCKER T T, WEDEL D J, SCHLICHTING J L 1994 Post-operative epidural analgesia and oral anticoagulant therapy. AnesthAnalg 79: 89–933. KINDLER C, SEEBERGER M, SIEGEMUND M, SCHNEI-DER M 1996 Extradural abscess complicating lumbar extraduralanaesthesia and analgesia in an obstretric patient. Acta AnaesthesiolScand 40: 858–614. DAHLGREN N, TORNEBRANDT K 1995 Neurological compli-cations after anaesthesia. A follow-up of 18,000 spinal and epiduralanaesthetic performed over three years. Acta Anaesthesiol Scand 39:872–805. MOEN V, DAHLGREN N, IRESTEDT L 2004 Severe neuro-logical complications after central neuraxial blockades in Sweden1990–1999. Anesthesiology 101: 950–96. AROMAA U, LAHDENSUU M, COZANITIS D A 1997 Severecomplications associated with epidural and spinal anaesthesias inFinland 1987–1993. A study based on patient insurance claims. ActaAnaesthesiol Scand 41: 445–527. WANG L P, HAUERBERG J, SCHMIDT J F 1999 Incidence ofspinal epidural abscess after epidural analgesia. Anesthesiology 91:1928–368. CAPDEVILA X, PIRAT P, BRINGUIER S, GAERTNER E, SIN-GELYN F J, BERNARD N, CHOQUET O, BOUAZIZ H, BON-NET F 2005 Continuous peripheral nerve blocks in hospital wardsafter orthopedic surgery. Anesthesiology 103: 1035–10459. SAKURAGI T, YASUNAKA K, HIRATA K, HORI K, DAN K 1998The source of epidural infection following epidural analgesia identi-fied by pulsed-field gel electrophoresis. Anesthesiology 89: 1254–610. KINDLER C H, SEEBERGER M D, STAENDER S E 1998Epidural abscess complicatiing epidural anaesthesia and analgesia.Acta Anaesth Scand 42: 614–2011. SAKURAGI T, YANAGISAWA K, DAN K 1995 Bactericidal activityof skin disinfectants on methicillin-resistant Staphylococcus aureus.Anest Analg 81: 555–812. HEBL J R 2006 The importance and implications of aseptic tech-niques during regional anesthesia. Regional Anesthesia and Pain Med-icine 31(4): 311–2313. WEDEL D J, HORLOCKER T T 2006 Regional anesthesia in thefebrile or infected patient. Regional Anesthesia and Pain Medicine31(4): 324–3314. KOINIG H, WALLNER T, MARHOFER P, KRENN C G, KLIM-SCHA W 1998 Regional anesthesia in the febrile patient: a possiblecontraindication? Acta Anesthesiol Scand 42 (Suppl 112): 155–615. BELAND B, PRIEN T, VAN AKEN H 1997 Spinal and regionalanesthesia in bacteremia. Anesthetist 46: 536–4716. HORLOCKER T T, WEDEL D J 2008 Infectious complications ofregional anesthesia. Best Pract Res Clin Anaesthesiol 22(3): 451–7517. HORLOCKER T T, WEDEL D J 2006 Regional anesthesia in theimmunocompromised patient. Regional Anesthesia and Pain Medi-cine 31(4): 334–4518. NSEIR S, PRONNIER P, SOUBRIER S, ONIMUS T, SAULNIERF, MATHIEU D, DUROCHER A 2004 Fatal streptococcal necro-tizing facilitis as a complication of axillary brachial plexus block. Br JAnaesth 92: 427–919. WONG D, RAYMOND N J 1998 Spinall epidural abscess. NewZeeland Medical Journal 111: 345–720. DRNOV[EK GLOBOKAR M, PAVER ER@EN V, NOVAK JAN-KOVI^ V 2010 Transverse myelitis following general and thoracicepidural anaesthesia. Signa Vitae 5(2): 29–3121. BROMAGE P R 1997 Neurological complications of subarachnoidand epidural anaesthesia. Acta Anaesth Scand 41: 439–44250 Period biol, Vol 113, No 2, 2011.Vesna Novak-Jankovi~ Infectious complications of regional anaesthesia and analgesia

Infectious complications of regional anaesthesia and analgesia

Abstract

Similar works

Full text

Available Versions

Hrčak - Portal of scientific journals of Croatia