Transtracheal Aspiration Research Articles

Inflammation and increased numbers of bacteria in the lower respiratory tract of horses within 6 to 12 hours of confinement with the head elevated.

Confinement of horses with their heads elevated for periods up to 24 hours was used to evaluate the extent and the effects of bacterial contamination of the equine lower respiratory tract. Significant (P < 0.05) increases in bacterial numbers (up to 10(9) colony forming units/mL in transtracheal aspirate derived samples) occurred within 6 or 12 hours in most horses. Pasteurella/Actinobacillus spp and Streptococcus spp were most commonly isolated. Lowering of the head for 30 minutes every 6 hours to facilitate postural drainage did not prevent multiplication of organisms to levels equivalent to those achieved by horses where the head was elevated for 24 hours. When horses were released from confinement and heads were no longer maintained in an elevated position, clearance of accumulated secretions and bacteria occurred within 8 to 12 hours. Thus, confinement with the head elevated resulted in significant bacterial contamination and multiplication within the lower respiratory tract during a period often encountered in routine management procedures, such as transportation. The clearance of accumulated secretions occurred over a prolonged period after release from such confinement.

Comparison of clinical signs, diagnostic findings, organisms isolated, and clinical outcome in dogs with bacterial pneumonia: 93 cases (1986-1991)

Summary Medical records were reviewed for 93 dogs with bacterial pneumonia from which transtracheal aspiration samples were obtained for culturing of Mycoplasma spp and aerobic bacteria. On the basis of culture results, there were 65 Mycoplasma-positive dogs, including 7 dogs for which only Mycoplasma spp were isolated, and 28 Mycoplasma-negative dogs. Most dogs were &gt; 5 years old, and differences in breed or gender distribution among the 3 groups of dogs were not detected. Hematologic and serum biochemical analysis results did not differ significantly between Mycoplasma-positive and Mycoplasma-negative dogs. Fifty-three of 93 (57%) dogs had a concurrent medical problem that may have predisposed them to developing bacterial pneumonia as a sequelae to aspiration or immunosuppression. Mycoplasma-positive dogs were significantly (P &lt; 0.005) more likely to have &gt; 1 species of bacteria isolated from their transtracheal aspiration samples. Clinical outcome was favorable when antimicrobials were selected on the basis of antimicrobial susceptibility results for the other bacterial isolates and not on results of the antimicrobial activity against Mycoplasma spp. It could not be determined whether Mycoplasma spp were primary pathogens or only opportunists.

Diagnosis and staging of bronchogenic carcinoma by transtracheal and transbronchial needle aspiration

Transbronchial needle aspiration (TBNA) has been used in diagnosis and staging of bronchogenic carcinoma. However, its true effectiveness seems uncertain and some models of needles are expensive. The aim of this study was to procure new experiences on this method. TBNA was performed in 194 patients with bronchogenic carcinomas. Two models of cheap, re-usable, cytological needles were used. In diagnostic application, TBNA was positive in 34 of 39 (87%) central tumors and in 31 of 45 (69%) peripheral nodules or masses. In 19 patients, TBNA was the only positive sample. In staging application, TBNA was positive in 41 of the 90 cases (46%) in which the spread of the tumor compressed the wall of the airway. When the trachea or bronchus was endoscopically normal at the site of the puncture, TBNA was only positive in 3 of 20 cases (15%). These results suggest that TBNA is effective as a diagnostic tool. However, it appears to be less effective in staging, where the attainment of a good yield with TBNA probably demands a positive computed tomography and the use of a histological needle.

New pathogens in pneumonia

It appears that many commonly recognized syndromes such as the ARDS may well be caused by agents that have only recently emerged as respiratory pathogens. HPS represents one such entity. It appears likely that the increasing pressure of antibiotic use as well as the reemergence of certain pathogens will continue to challenge the clinician. Paramount to the identification and treatment of unusual pneumonias will be the degree with which an effort is made to make an etiologic diagnosis through sputum examination, transtracheal aspirate, bronchoscopy, or lung biopsy. Although pneumococcal pneumonia is the most common community-acquired pneumonia seen by practicing physicians, in all likelihood from time to time a physician will encounter pneumonia caused by one of the unusual pathogens described in this article or else by an altogether new pathogen.

Review of 40 cases of lung abscesses in foals and adult horses

A retrospective study of 40 horses with primary lung abscesses without pleuropneumonia showed that lung abscesses occurred predominantly in young horses, usually in foals aged < or = 6 months. Hyperfibrinogenaemia was present in all but 2 horses, and other common clinical and haematological findings were hyperthermia, tachycardia, polypnoea, and neutrophilic leucocytosis. The most common bacterial species isolated from transtracheal aspirates were Streptococcus zooepidemicus (20/34) and Rhodococcus equi (13/34). Most horses (23/27) discharged from the hospital were long term survivors. Of the 19 horses for which a follow up was available, 12 raced or performed the task for which they were intended. None of the indicators evaluated in this study could reliably predict the bacterial species involved or the outcome.

Use of serology to diagnose pneumonia caused by nonencapsulated Haemophilus influenzae and Moraxella catarrhalis.

Antibodies against nonencapsulated Haemophilus influenzae and Moraxella (Branhamella) catarrhalis were measured by ELISA in paired sera from 158 adult patients with pneumonia. A mixture of 10 clinical isolates of each species was used as antigen. Eleven patients (7%) showed significant increases in antibody to H. influenzae. In 3 of them, the organism was isolated from transtracheal aspirate and in another 7 from sputum, nasopharynx, or both. Six patients with nonencapsulated H. influenzae in transtracheal aspirate cultures did not show any antibody increase. Six patients had significant increases in antibody to M. catarrhalis. The organism was isolated in transtracheal aspirates from 1 of them and in sputum and nasopharynx (or both) from another 3. Two patients with M. catarrhalis in transtracheal aspirate cultures showed no antibody response. In conclusion, the serologic methods increased the possibility to diagnose infections caused by the two agents but had low sensitivity.

Detection of Bacteroides fragilis in clinical specimens by PCR

The direct detection of Bacteroides fragilis from clinical specimens was examined by using the PCR method for amplifying a specific fragment of the glutamine synthetase gene from B. fragilis. By this method, all five B. fragilis strains tested were detected, but DNAs from anaerobic bacteria of 24 other species tested, from aerobic bacteria of 12 species tested, and from human leukocytes were not amplified. Using the nested PCR method, we were able to detect as little as one bacterial cell or 100 fg of chromosomal DNA of B. fragilis. A total of 39 clinical specimens, which consisted of 19 bronchial aspirates, 10 percutaneous lung aspirates, 2 transtracheal aspirates, 6 pleural fluid specimens, and 2 pus specimens, were tested. All four culture-positive samples, of which two were bronchial aspirates, one was pleural fluid, and one was pus, were positive by PCR. Among 35 culture-negative samples, 2 bronchial aspirates were positive by PCR. One was from a patient whose two previous samples were positive by both culture and PCR. It had been submitted for culture several hours after collection, and clindamycin had been administered to the patient before collection of the specimen. The other bronchial aspirate positive by PCR was from a pneumonia patient who had also been administered clindamycin. We believe that B. fragilis was present in these two specimens but that either it was dead, it was below the level detectable by culture, or the process of anaerobic culture was unsuccessful. Thus, the PCR method may be considered useful for the sensitive and rapid detection of anaerobes in clinical specimens.

An evaluation of pathogens in patients with bronchopulmonary infection by transtracheal aspiration: December 1978-March 1993

We performed transtracheal aspiration (TTA) in 1165 patients, who were suspected to have bronchopulmonary infection, from December 1978 to March 1993. We isolated pathogens from TTA in 806 patients (69.2%). We isolated H. influenzae (62 cases), S. pneumoniae (39 cases) and M. catarrhalis (24 cases) in patients with acute bronchitis, S. pneumoniae (65 cases), alpha-Streptococcus sp. (52 cases), H. influenzae (32 cases) and S. aureus (29 cases) in patients with pneumonia or lung abscess and H. influenzae (174 cases), S. pneumoniae (84 cases), P. aeruginosa (81 cases) and M. catarrhalis (42 cases) in patients with chronic lower respiratory tract infection. Anaerobic bacteria isolated from TTA included Peptostreptococcus sp. (19 cases), Bacteroides sp. (19 cases) and others. Mycoplasma pneumoniae was isolated from TTA in 8 patients with pneumonia without other organisms. Virus isolated from TTA included Rhinovirus (6 cases) and others. These results suggest that various pathogens affect the pathogenesis of bronchopulmonary infection. Therefore, we must diagnose the bronchopulmonary infection by the correct methods such as TTA.

The role of viral infection in adults with bronchopulmonary infections

We isolated the virus from the respiratory specimens of 16 patients (7.9%) when we investigated the bronchopulmonary infections of 203 adult patients by the viral isolation method for the diagnosis of the viral infection and transtracheal aspiration (TTA) for taking directly the specimen from the lower respiratory tract. The bronchopulmonary infections, isolated the virus, consisted of acute bronchitis (3 cases), pneumonia (8 cases) and the acute exacerbation of chronic lower respiratory infection (5 cases). The positive viral isolation consisted of Rhinovirus (11 strains), Herpes simplex virus I (3 strains), Parainfluenza virus III (1 strain) and Respiratory syncytial virus (1 stain). There were 9 transtracheal aspirates, 8 pharyngeal swabs and 5 nasal washings in the positive viral specimens. We experienced 5 cases who had the same virus isolated from both the upper respiratory tract and the lower respiratory tract. H. influenzae, P. aeruginosa and other bacteria were found in 14 of the 16 TTA cultures. These results suggest that the role of the viral infection is important either independently or relating the bacterial infection in the adult bronchopulmonary infections.

A clinical study of Pseudomonas pneumonia diagnosed by transtracheal aspiration

We performed a clinical study of 16 cases (18 episodes) of Pseudomonas pneumonia by transtracheal aspiration (TTA) from April 1983 to March 1993. The isolation rate of Pseudomonas aeruginosa (P. aeruginosa) among 235 episodes of pneumonias with positive microorganism by TTA was 7.7%. All patients had one or more underlying disease. The most frequent underlying disease was chronic lower respiratory tract infection, followed by lung epidermoid cell carcinoma. More than half of the cases had been given antibiotics prior to the occurrence of pneumonia, and administration of adrenal corticosteroid, heavy smoking habit, and aspiration were seen as other predisposing factors concerning the onset of pneumonias. Monomicrobial infection of P. aeruginosa was 61.1%, and polymicrobial infection containing P. aeruginosa was 38.9%. Community-acquired pneumonia was 61.1% and hospital-acquired pneumonia was 38.9%; the rates of polymicrobial infections and prior administration of antibiotics were higher in the latter group. Mortality due to Pseudomonas pneumonia was 27.8% and the levels of serum albumin and total protein at the onset of pneumonia were significantly lower in the fatal cases than in the recovered cases. It was considered that not only general underlying disease which weaken the immunological resistance of the host, but local bronchial lesion was also important to the onset of the Pseudomonas pneumonia. Also, nutrition is an important prognostic factor on the host's side.

A clinical study of respiratory infections due to mucoid Pseudomonas aeruginosa diagnosed by transtracheal aspiration

We performed a clinical study of 20 cases (33 episodes) of respiratory infections due to mucoid Pseudomonas aeruginosa by transtracheal aspiration (TTA) in the recent 10 years. There was only one pneumonia without underlying chronic lower respiratory infection (CLRTI) case positive for mucoid P. aeruginosa and others were all CLRTI among 33 TTA trials. In contrast, nonmucoid P. aeruginosa was recovered from 9 cases of respiratory infections without underlying CLRTI among 46 TTA trials. Monomicrobial infection of mucoid P. aeruginosa was 69.7%, and polymicrobial infection containing mucoid P. aeruginosa was 30.3%, and Haemophilus influenzae was the most frequent microorganism recovered with mucoid P. aeruginosa. The recovery rate of mucoid P. aeruginosa among P. aeruginosa-colonized cases was 56.3% in diffuse panbronchiolitis, and that was 42.9% and 40.0% in bronchiectasis and chronic bronchitis, respectively. Mortality due to pneumonia with nonmucoid P. aeruginosa was 46.1%, but there was no fatal pneumonia case with mucoid P. aeruginosa. In CLRTI, laboratory data were not remarkably different between mucoid and non-mocoid P. aeruginosa-colonized cases. Thus, these results suggest that mucoid P. aeruginosa is a more important organism in persistent infections in the lower respiratory tract compared with nonmucoid P. aeruginosa, and further investigations is required on the mechanism and clinical role of this infection.

Anaerobic respiratory infection--evaluation of methods of obtaining specimens

Anaerobic cultures were performed on various kinds of specimens obtained from 67 patients with respiratory infections. The infections consisted of 33 cases of pneumonia, 14 cases of lung abscess, 6 cases of pyothorax, 9 cases of chronic lower respiratory tract infection, and 5 cases of infection of pulmonary cyst. Specimens included bronchoscopic specimens obtained using a single tube or protected catheter brush (PCB), transtracheal aspirate, percutaneous lung aspirate, aspirate using a suction tube through the tracheostomy or intubation tube, and pleural fluid. Anaerobes were isolated in 80% of pyothorax, 43% of lung abscess, and 15% of pneumonia (42% of aspiration pneumonia), respectively. Anaerobes isolated frequently in respiratory infections included Prevotella spp., Fusobacterium spp., and Peptostreptococcus spp. In regard to the type of specimen, bronchial aspirate obtained by bronchoscopy was useful in examination of pneumonia, and was useful as percutaneous lung aspirate in examination of lung abscess. But there was discrepancy of culture results between specimens obtained by different methods in the same patient. To confirm anaerobes as pathogens in respiratory infections, it is necessary to select an appropriate method to obtain specimens and to interpret the culture results comprehensively.

Lack of residual lung damage in horses in which Rhodococcus equi-induced pneumonia had been diagnosed

Summary The effect of prior Rhodococcus equi-induced pneumonia on pulmonary health was investigated in 5 horses (&lt; 24 months old) using endoscopy, radiography, hematologic and bronchoalveolar lavage analyses, and pulmonary function testing. Rhodococcus equi-induced pnuemonia had been diagnosed in principal horses when they were foals. Diagnosis was based on positive results of transtracheal aspiration and thoracic radiography at the time of initial clinical examination. Results of reevalution of the respiratory system of these horses (R + ) were compared with those of 5 age-matched healthy horses (R −) that lacked clinical or historical evidence of foalhood pneumonia. Significant differences in variables between the 2 groups of horses were not evident. In both groups, most horses had radiographic evidence of an accentuated bronchointerstitial pattern, although results of analysis of bronchoalveolar lavage specimens were normal and mononuclear cells predominated. Variability in results of the pulmonary function tests was observed within and between the 2 groups of horses. Only normalized dynamic lung compliance was slightly lower in the previously infected horses, but this difference was not significant. We concluded that horses previously infected with and successfuly treated for R equi-induced pneumonia do not have detectable evidence of residual lung damage.

Etiology of Community-acquired Pneumonia: Evaluation by Transtracheal Aspiration, Blood Culture, or Serology

In a 5-year period, 254 patients with community-acquired pneumonia were attended to. Transtracheal aspiration (TTA) could be performed on 119 patients, blood cultures were performed on 201 patients, and 74 patients underwent serologic examinations. By use of these procedures, an etiologic diagnosis was established in 93 cases. Streptococcus pneumoniae was the most common pathogen as it was found in 35 cases. Eleven of these 35 patients (31.4 percent) had pneumococcemia, and the mortality in this group was 27.3 percent. None of the patients with pneumococcal pneumonia and negative blood culture died. Haemophilus influenzae was the only isolated pathogen from transtracheal aspirated sputum in 16 cases and accounted for 17.5 percent of pneumonias in previous healthy individuals under 50 years of age. Mycoplasma pneumonia infections, Legionella pneumophila infections, and Chlamydia infections were found in ten, eight, and three cases, respectively. The overall agreement between microscopy and culture of respiratory secretions obtained by TTA was 58.8 percent, and microscopy can be a guide when choosing the initial antibiotic treatment. No statistically significant difference in the rate of isolating bacteria among patients treated with antibiotics prior to TTA and patients not previously treated with antibiotics was seen. When contraindications were respected, we found TTA to be a safe procedure.

Diagnostic problems in lower respiratory tract infections

The main problems of diagnosis in lower respiratory tract infection are the differentiation of infection from colonization or contamination, and the isolation of a reliable and true pathogen. The clinical findings and differentiation of patients into those with pneumonia or infective exacerbations of chronic bronchitis should provide a definitive early diagnosis. Expectorated sputum may be unreliable in pneumonia, because of contamination by oropharyngeal flora. Although blood cultures may be negative, they provide a precise diagnosis and should be obtained in all pneumonias admitted to hospital. Other more invasive procedures are transtracheal needle aspiration, fibrebronchoscopic techniques including protected specimen brush and bronchoalveolar lavage with quantitative culturing and cytological analysis, transthoracic needle aspiration, thoracoscopy--guided biopsy and open lung biopsy. Any invasive procedure in a severely ill patient should be carefully directed weighing the risks as well as the benefits, whilst taking the underlying disease and expected survival into consideration.

Bacteriologic Diagnosis in Anaerobic Pleuropulmonary Infections

Four types of specimens are viewed as having established reliability for the detection of anaerobic bacteria that cause pulmonary infections: blood, pleural fluid, transtracheal aspirates, and transthoracic aspirates. Blood cultures are obviously appropriate diagnostic methods but are positive in <2% of cases [ 1 ] in which the diagnosis is established by alternative methods. Pleural fluid also has unchallenged merit as a specimen but only for the minority of patients with empyema. For most patients with infections restricted to the pulmonary parenchyma, the only diagnostic methods with clearly established merit involve transtracheal aspiration and transthoracic needle aspiration. Transthoracic needle aspiration was done extensively in the preantibiotic era, but more recently its use has been largely restricted to a relatively few practitioners and a highly selective patient population. We are not aware of any practitioner who is doing transthoracic needle aspirations with any frequency for patients with anaerobic pulmonary infections, although the merit of this technique has been established in at least two studies of lung abscess by investigators in France [2] and Spain [3]. There has been extensive experience with transtracheal aspiration that verifies the utility of this technique in obtaining uncontaminated specimens from the lower airways of patients with anaerobic pulmonary infections [4-7] and also establishes the role of anaerobes in lung abscess and aspiration pneumonia [1, 5-7]. Transtracheal aspiration became popular in the late 1960s but almost disappeared from clinical practice after ~ 10 years of extensive use. Several factors contributed to this decline in its use: reports of severe complications, escalating interest in alternative techniques such as fiberoptic bronchoscopy, failure of hospitals to credential qualified physicians for performing this technique (as they do for bronchoscopy), and a common perception that empirical use of antibiotics has largely supplanted any need to es-

Anaerobic Bacterial Infections of the Lung and Pleural Space

In 193 reviewed cases of pleuropulmonary infections involving anaerobic bacteria, the predominant clinical syndromes were aspiration pneumonia, lung abscess, and empyema. Most patients had an indolent infection with tissue necrosis (abscess or bronchopulmonary fistula) at initial presentation. Nevertheless, many had a more fulminant disease course resembling that of pneumococcal pneumonia. Transtracheal aspiration was the procedure most commonly used to obtain uncontaminated specimens for anaerobic culture; since this procedure now is seldom employed, pulmonary infections due to anaerobes rarely have an etiologic diagnosis at present. The dominant pathogens are Peptostreptococcus, Bacteroides, Prevotella, and Fusobacterium species. Although clindamycin is widely considered to be the antibiotic of choice, proper therapeutic trials would probably prove many antibiotics to be effective for the treatment of anaerobic pleuropulmonary infections.

The role of bacterial super infection in extensive pulmonary tuberculosis: Data from protected brush cultures in untreated patients from the University of South Alabama Medical Center, Mobile, Alabama, USA

Pulmonary tuberculosis (TB) and bacterial pneumonia are both characterized by fever, cough, and purulent sputum production. Although TB alone can cause these symptoms, the possibility of a concomitant bacterial pneumonia has led some clinicians to treat these patients empirically with antibacterial agents. Neither the benefit of such empiric antibiotic therapy nor transtracheal aspirate cultures from patients with pulmonary TB have yielded consistent results. Consequently, we performed a prospective study to obtain lower airway secretions via a bronchoscopic protected specimen brush (PSB) technique for quantitative aerobic and anaerobic cultures from untreated patients with extensive pulmonary TB (defined as cavitary disease or involvement of ≥ 3 segments). We obtained bronchoscopic samples from 3 untreated men aged 21,61, and 60 years with extensive pulmonary TB. There was no significant bacterial growth (aerobic or anaerobic) from the specimens obtained. These results, therefore, do not support the hypothesis that bacterial pneumonia is a common concomitant of extensive pulmonary TB.

COMMUNITY-ACQUIRED PNEUMONIA CAUSED BY MIXED AEROBIC PATHOGENS

A retrospective literature review was conducted to assess the role of mixed aerobic pathogens in community-acquired pneumonia (CAP). Studies were analyzed that presented data on the etiology of CAP as well as the source of culture specimen. Emphasis was placed on investigations with sources from usually sterile sites such as blood, transtracheal aspirate, and lung puncture. Other sources evaluated included fiberoptic bronchoscopy with sterile brush and quantitative microbiology and expectorated sputum if analyses of adequacy of specimen were used. The rate of identification of mixed aerobic pathogens ranged from 2.2% (lung puncture) to 16.7% (transtracheal aspirate). The most commonly identified combination was Streptococcus pneumoniae and Haemophilus influenzae. At least 30 patients with S. pneumoniae plus Legionella species have been described. Despite the limitations of this investigation, these findings probably explain in part the ongoing morbidity and mortality from CAP. If response to a “single-pathogen‘’ CAP is not noted within 24–48 hours, either an invasive procedure or empiric therapy to cover the most likely combinations should be instituted.

Clinical study of acute bacterial bronchitis

Eighty-two episodes (77 cases) in which any pathogens were isolated from transtracheal aspiration (TTA) and which satisfied the new clinical criteria of acute bacterial bronchitis were clinically evaluated. Major pathogens isolated from TTA included H. influenzae, S. pneumoniae and B. catarrhalis. Fever developed in 91.5% of the patients. Sputum volume averaged 16.3 +/- 14.9 ml per day. All the patients suffered from coughs, which were so severe as to disturb sleep in 8.5% of the patients. Inflammatory indices included WBC 9738.0 +/- 3158.5/microliter, CRP 10.1 +/- 7.9 mg/dl and ESR 69.0 +/- 38.8 mm/hr on average, PaO2 fell in most cases. Compared to the group of patients with acute bacterial bronchitis from which a single pathogen was isolated, the numbers of elderly patients and smokers were significantly more in the group of multiple pathogens isolated from TTA. Prior episodes related to the development of acute bacterial bronchitis were upper respiratory inflammation in 46.3% and undergoing bronchoscopy in 4.9% of the patients. Antibiotics therapy cured acute bacterial bronchitis in 96.3% of the patients. In spite of treatment, 3 patients developed pneumonia and died.