Traqueobronquite associada à ventilação mecânica: uma atualização / Ventilator-associated tracheobronchitis: an update

RESUMO As infecções do trato respiratório inferior associadas à ventilação mecânica são uma das complicações mais frequentes em pacientes em ventilação mecânica. Há muitos anos, a traqueobronquite associada à ventilação mecânica tem sido considerada uma doença que não demanda antibioticoterapia. Na última década, diversos estudos demonstraram que a traqueobronquite associada à ventilação mecânica deve ser considerada um processo intermediário que leva à pneumonia associada à ventilação mecânica, uma vez que apesar de ter impacto limitado sobre a mortalidade dos pacientes gravemente enfermos internados nas unidades de terapia intensiva, em contrapartida, demonstra associação significativa com o aumento dos custos hospitalares desses pacientes, assim como do tempo de internação na unidade de terapia intensiva e hospitalar, do uso de antibióticos, e da duração da ventilação mecânica. Embora ainda necessitemos de evidências científicas mais robustas, especialmente no que tange às modalidades terapêuticas, os dados atuais a respeito da traqueobronquite associada à ventilação mecânica salientam que há desfechos suficientemente importantes que exigem vigilância epidemiológica e controle clínico adequados.

ABSTRACT Ventilator-associated lower respiratory tract infection is one of the most frequent complications in mechanically ventilated patients. Ventilator-associated tracheobronchitis has been considered a disease that does not warrant antibiotic treatment by the medical community for many years. In the last decade, several studies have shown that tracheobronchitis could be considered an intermediate process that leads to ventilator-associated pneumonia. Furthermore, ventilator-associated tracheobronchitis has a limited impact on overall mortality but shows a significant association with increased patient costs, length of stay, antibiotic use, and duration of mechanical ventilation. Although we still need clear evidence, especially concerning treatment modalities, the present study on ventilator-associated tracheobronchitis highlights that there are important impacts of including this condition in clinical management and epidemiological and infection surveillance.

Nosocomial tracheobronchitis in mechanically ventilated patients: frequency, aetiology and outcomes

The aim of this study was to determine the frequency, etiology, microbiological sensitivity and outcomes of nosocomial tracheobronchitis [NTB] in mechanically ventilated patients admitted in surgical intensive care unit. A prospective observational study was conducted in the Surgical Intensive Care Unit [ICU], Department of Anaesthesiology, Civil Hospital Karachi from April 2009 to April 2010. All the patients on mechanical ventilator for more than 48 hours in the ICU were evaluated according to the criteria for the diagnosis of nosocomial tracheobronchitis [NTB]. Outcomes of the patients were measured in terms of development of nosocomial pneumonia after NTB, length of ICU stay, duration of mechanical ventilation and mortality in the ICU. Two hundred and eighteen patients were evaluated for this study. Nosocomial tracheobronchitis was diagnosed in 72 patients. The frequency of NTB was 33%. Sixteen types of organisms were identified, 61.23% cases were poly-microbial, while in the remaining 39.7% cases single organism was isolated. The most common organism was gram negative Acinetobacter spp [51%], followed by Klebsiella spp [29%] and Pseudomonas aeruginosa [16.6%]. Escherichia coli and other gram negative rods were 13.8 % and 11.4%, respectively. There were 4.16 % cases of MRSA isolated in patients who had positive cultures for gram negative organ-isms [poly-microbial]. Ceftriaxone was given in 44% cases as empirical therapy and continued in 33% cases after microbial sensitivity and replaced in 11% cases after culture sensitivity to Cefiperazone + salbactum and in 14% cases cefiperazone was given in combination therapy. Imipenem was used in 28.5% of patients. Quinolones were used in 19% contaminated cases of gut surgeries. Nosocomial tracheobronchitis was significantly associated with increased length of ICU stay and longer duration of mechanical ventilation in our patients when compared to those patients who did not develop NTB [p<0.001]. Moreover, out of 72 patients, 11 developed subsequent nosocomial pneumonia. There was no statistically significant difference noted in mortality rates among patients with NTB and without NTB [43% vs. 41%]. The mortality was related to concomitant comorbitidies, primary cause and surgical outcomes. Nosocomial tracheobronchitis is a common infection in mechanically ventilated patients that significantly affects the development of pneumonia and length of ICU stay for the patients. This study was an insight to the state of NTB in an ICU setup. The higher frequency of NTB demands such studies to set protocols in every intensive care unit

Traqueobronquitis asociada al ventilador (TAV), implicancias del diagnostico clinico y microbiologico en una cohorte de pacientes en ventilacion mecanica / Ventilator associated tracheobronchitis (VAT), implications of clinical and microbiological diagnosis in a cohort of mechanical ventilated patients

Tratar con antibioticos una TAV, proceso intermedio entre colonizacion y neumonia asociada al ventilador (NAV), reduciria la incidencia de NAV y sus consecuencias. Metodos: seguimiento clinico diario y cultivos cuantitativos rutinarios de aspirado traqueal (CRAT) bisemanales hasta el destete en 323 pacientes en ventilacion mecanica. Cuando se sospecho clinicamente infeccion (2/3 criterios), si habia infiltrado radiografico nuevo, se diagnostico NAV y se practico lavado broncoalveolar (LBA) y sin infiltrado nuevo, se diagnostico TAV, se consideraron los aislamientos del LBA positivos (¡Ý 104 unidades formadoras de colonias (ufc)/ml) para la NAV) y del CRAT positivos (¡Ý 103 y < 106 ufc/ml (bajo recuento) y ¡Ý 106 ufc/ml (alto recuento)) para TAV. Resultados: 443 de 2.309 radiografias mostraban ausencia de infiltrado o infiltrado difuso estable; 92 cumplian criterios de TAV, 13 de estas, 12 con CRAT ¡Ý 106 ufc/ml, tuvieron una NAV en los siguientes 3 dias (12 con cultivo de LBA ¡Ý104 ufc/ml). En estas NAV, 11/15 (73.3%) de los pat¨®genos coincidian con los de la TAV precedente. Desde otro punto de vista, 10 TAVs ocurrieron durante la semana posterior a una NAV, solo 4/12(33.3%) patogenos de estas coincidian con los de la TAV, p=0.045 comparando con TAV precediendo a NAV. Setenta TAVs no tuvieron relacion temporal con NAVs. Discusion: este estudio sugiere que tratar con antibioticos las TAVs podria prevenir una NAV en 14% de los casos, exponiendo a un uso innecesario al 86%, lo cual limitaria fuertemente la conveniencia de tratar las TAVs para prevenir las NAVs.

The ventilator associated tracheobronchitis (VAT) is a process between airway colonization and ventilator-associated pneumonia (VAP). The antimicrobial therapy of VAT wouldreduce the incidence of VAP and its consequences. Methods: Daily follow up and twice a week routine quantitative culture of endotracheal aspirates (CETA) up to weaning were performed in 323 mechanically ventilated patients.When a lower respiratory tract infection was suspected (2/3 clinical criteria), if a new radiographic inf¨ªltrate was present, VAP was diagnosed and a bronchoalveolar lavage (BAL) culture was performed; if a radiographic infiltrate was absent, VAT was diagnosed. The bacteriological criteria for diagnosis were a BAL culture positive (¡Ý 104 colony forming units - cfu/ml) for VAP and a CETA positive culture (low count from ¡Ý 103 to < 106 cfu/ml and high count ¡Ý 106 ufc/ml) for VAT. Results: In 443 of 2,309 radiographs an infiltrate was absent or was diffuse and stable; 92 of them met diagnostic clinical criteria for VAT. In 13 (12 with CETA culture ¡Ý 106 cfu/ml), a VAP episode happened during the following 3 days (12 with BAL culture ¡Ý 104 cfu/ml). In 11/15 (73.3%) VAP cases, the isolated pathogens were the same that had been present in the preceding VAT episode. On the other side, ten episodes of VAT were diagnosed during the 7 days after the VAP. Only 4/12 (33.3%) isolated pathogens were the same than those isolated in the VAT preceding the VAP, p=0.045. Seventy VATs had not any temporal relationship with episodes of VAP. Discusion: This study suggests that antimicrobial therapy could prevent a VAP in 14% of the TAV cases. Therefore, exposure to antibiotics was unnecessary in 86% of cases. This finding could represent a severe limitation to the recommendation of treating TAVs with antibiotics to prevent VAPs.

Traqueítis bacteriana

La traqueítis bacteriana es una entidad potencialmente fatal que ha reaparecido en la última década con inusitado auge. A propósito de su detección en nuestro servicio decidimos realizar un estudio retrospectivo en el Hospital Universitario de la Misericordia de Santa Fe de Bogotá entre enero de 1990 y julio de 1994. Se revisaron 88 historias de pacientes con diagnósticos clínico sugestivo de traqueítis bacteriana pero sólo 13 pacientes cumplieron con el requisito de confirmación endoscópica del diagnóstico para ser considerados en el presente trabajo. La edad osciló entre 1 y 7 años, predominando el sexo masculino. Existió antecedente de infección respiratoria previa en el 54 por ciento, los síntomas más frecuentes fueron fiebre, tos perruna y dificultad respiratoria; los hemogramas mostraron leucocitosis, neutrofilia y aumento de la VSG. En la endoscopia se observó exudado traqueal, membranas purunlentas y úlceras; en solo cultivo se aisló Staphylococcus aureus. El 62 por ciento requirió permeabilizar la vía aérea, 3 con traqueostomía y 5 con tubo orotraqueal. El 46 por ciento se manejó con oxacilina y todos evolucionaron satisfactoriamente.

Laringotraqueobronquitis: revisión de cinco años en el Hospital del Niño / Laryngotracheobronchitis: review of 5 years at the Hospital del Niño

Se tuvo un total de ochenta y cinco pacientes con diagnóstico de laringotraqueobronquitis, la mayor incidencia correspondió al grupo etareo de seis meses a dos años, sexo masculino y eutróficos; la frecuencia más importante se presentó en otoño e invierno y la mayoría de casos correspondió a crup grado II. En general hubo mejoría del cuadro clínico con el uso exclusivo de vaporización. La mortalidad se relacionó con la informada en la literatura y puede disminuir de aplicarse una serie de medidas aquí recomendadas. No fué importante el auxilio de pruebas laboratoriales ó de radiología