Transbronchial biopsy during mechanical ventilation

Transbronchial Forceps Biopsy in the Intensive Care Unit: A Systematic Review and Meta-analysis

BACKGROUND

A transbronchial forceps lung biopsy performed in mechanically ventilated patients with respiratory failure of unknown etiology has significant uncertainty of diagnostic yield and safety along with sparse literature. This study investigated the complication rate of transbronchial biopsies in mechanically ventilated patients in the intensive care unit and its ability to obtain a diagnosis and change current therapy.

METHODS

PubMed, Ovid MEDLINE, and Ovid Cochrane Central Register of Controlled Trials databases were systematically searched for all publications of transbronchial lung biopsies in mechanically ventilated patients. We pooled the results of individual studies using random-effects meta-analysis models to achieve the summary proportions.

RESULTS

Of the identified 9 observational studies with a total of 232 patients undergoing a transbronchial biopsy, complications occurred in 67 patients [25.2%; 95% confidence interval (CI), 11.5%-42.0%; I2=70.0%]. Pneumothorax occurred in 24 patients (9.5%; 95% CI, 4.5%-16.2%; I2=15.9%) and bleeding in 18 patients (8.9%; 95% CI, 4.1%-15.3%; I2=0%). A diagnosis was given in 146 patients (62.9%; 95% CI, 56.0%-69.1%; I2=74.6%), with 103 of 210 patients (49.0%; 95% CI, 44.6%-55.1%; I2=74.9%) having a change in treatment.

CONCLUSION

The results of this meta-analysis suggest that a transbronchial forceps biopsy when performed in mechanically ventilated patients with respiratory failure of unclear etiology had a moderate complication rate. These biopsies resulted in varied diagnoses with a high rate of management change. Randomized controlled trials are necessary to identify the ideal patients to perform a transbronchial forceps biopsy on in the intensive care unit.

Clinical Value of Bronchoscopy in Acute Respiratory Failure

Bronchoscopy may be considered the “added value” in the diagnostic and therapeutic pathway of different clinical scenarios occurring in acute respiratory critically ill patients. Rigid bronchoscopy is mainly employed in emergent clinical situations due to central airways obstruction, haemoptysis, and inhaled foreign body. Flexible bronchoscopy (FBO) has larger fields of acute applications. In intensive care settings, FBO is useful to facilitate intubation in difficult airways, guide percutaneous dilatational tracheostomy, and mucous plugs causing lobar/lung atelectasis. FBO plays a central diagnostic role in acute respiratory failure caused by intra-thoracic tumors, interstitial lung diseases, and suspected severe pneumonia. “Bronchoscopic” sampling has to be considered when “non-invasive” techniques are not diagnostic in suspected ventilator-associated pneumonia and in non-ventilated immunosuppressed patients. The combined use of either noninvasive ventilation (NIV) or High-flow nasal cannula (HFNC) with bronchoscopy is useful in different scenarios; the largest body of proven successful evidence has been found for NIV-supported diagnostic FBO in non-ventilated high risk patients to prevent and avoid intubation. The expected diagnostic/therapeutic goals of acute bronchoscopy should be balanced against the potential severe risks (i.e., cardio-pulmonary complications, bleeding, and pneumothorax). Expertise of the team is fundamental to achieve the best rate of success with the lowest rate of complications of diagnostic and therapeutic bronchoscopic procedures in acute clinical circumstances.

Bronchoscopy in intubated and non-intubated intensive care unit patients with respiratory failure

Bronchoscopy is one of the important tool for the pulmonary and critical care physicians to diagnose and treat various pulmonary conditions. It is increasingly being used by the intensivist due to its safety and portability. The utilization of bronchoscopy in the intensive care unit (ICU) has made the diagnosis and treatment of many conditions more feasible to intensivists. Sedation, topical or intravenous, usually helps better tolerate the procedure. However, the risks and benefits of bronchoscopy should be carefully considered in critically ill patients. The hypoxic patients in ICU pose a challenge as hypoxemia is one of the known complications of bronchoscopy, and this risk is exacerbated in patients with hypoxic respiratory failure. Bronchoscopy is relatively contraindicated in patients with severe hypoxemia and coagulopathy. However, bronchoscopy in hypoxic patients can have diagnostic as well as therapeutic implications. In patients with hypoxic respiratory failure, the use of non-invasive ventilation (NIV) during bronchoscopy has been shown to reduce the risk of intubation. On the other hand, bronchoscopy in mechanically ventilated patients is not contraindicated and has been widely used. Staying focused, monitoring vital signs closely, limiting the scope time in the airway, and understanding patient’s physiology may help decrease risk of complications. In this review, we discuss indications, techniques, complications, and yield associated with bronchoscopy in critically ill hypoxic patients.

Diagnostic yield, safety, and impact of transbronchial lung biopsy in mechanically ventilated, critically ill patients: a retrospective study

Background

Pulmonary infiltrates of variable etiology are one of the main reasons for hypoxemic respiratory failure leading to invasive mechanical ventilation. If pulmonary infiltrates remain unexplained or progress despite treatment, the histopathological result of a lung biopsy could have significant impact on change in therapy. Surgical lung biopsy is the commonly used technique, but due to its considerable morbidity and mortality, less invasive bronchoscopic transbronchial lung biopsy (TBLB) may be a valuable alternative.

Methods

Retrospective, monocentric, observational study in mechanically ventilated, critically ill patients, subjected to TBLB due to unexplained pulmonary infiltrates in the period January 2014 to July 2019. Patients’ medical records were reviewed to obtain data on baseline clinical characteristics, modality and adverse events (AE) of the TBLB, and impact of the histopathological results on treatment decisions. A multivariable binary logistic regression analysis was performed to identify predictors of AE and hospital mortality, and survival curves were generated using the Kaplan-Meier method.

Results

Forty-two patients with in total 42 TBLB procedures after a median of 12 days of mechanical ventilation were analyzed, of which 16.7% were immunosuppressed, but there was no patient with prior lung transplantation. Diagnostic yield of TBLB was 88.1%, with AE occurring in 11.9% (most common pneumothorax and minor bleeding). 92.9% of the procedures were performed as a forceps biopsy, with organizing pneumonia (OP) as the most common histological diagnosis (54.8%). Variables independently associated with hospital mortality were age (odds ratio 1.070, 95%CI 1.006–1.138; p = 0.031) and the presence of OP (0.182, [0.036–0.926]; p = 0.040), the latter being confirmed in the survival analysis (log-rank p = 0.040). In contrast, a change in therapy based on histopathology alone occurred in 40.5%, and there was no evidence of improved survival in those patients.

Conclusions

Transbronchial lung biopsy remains a valuable alternative to surgical lung biopsy in mechanically ventilated critically ill patients. However, the high diagnostic yield must be weighed against potential adverse events and limited consequence of the histopathological result regarding treatment decisions in such patients.

Pulmonary Toxoplasmosis Diagnosed on Transbronchial Lung Biopsy in a Mechanically Ventilated Patient

Toxoplasma gondii is a protozoan parasite that infects up to a third of the world's population. Infection is mainly acquired by ingestion of food or water that is contaminated with oocysts shed by cats or consuming undercooked meat containing tissue cysts. Primary infection is subclinical in immunocompetent hosts. Invasive toxoplasmosis often manifests as cerebral toxoplasmosis in immunosuppressed patients. In persons living with human immunodeficiency virus (HIV), toxoplasmosis occurs when CD4 counts are very low and is considered an acquired immunodeficiency syndrome (AIDS) defining illness. Pulmonary toxoplasmosis is rarely seen in the highly active antiretroviral therapy era. The diagnosis can be challenging due to the nonspecific nature of clinical and radiographic findings. In this report, we present a case of pulmonary toxoplasmosis in a new onset AIDS patient, which was initially clinically misdiagnosed as Pneumocystis jiroveci pneumonia (PJP). Due to a poor response to treatment for PJP, the patient underwent a transbronchial lung biopsy, which led to the diagnosis of pulmonary toxoplasmosis.

The use of bronchoscopy in critically ill patients: considerations and complications

INTRODUCTION

Flexible bronchoscopy has been well established for diagnostic and therapeutic purposes in critically ill patients. Areas covered: This review outlines the clinical evidence of the utility and safety of flexible bronchoscopy in the intensive care unit, as well as specific considerations, including practical points and potential complications, in critically ill patients. Expert commentary: Its ease to learn and perform and its capacity for bedside application with relatively few complications make flexible bronchoscopy an indispensable tool in the intensive care unit setting. The main indications for flexible bronchoscopy in the intensive care unit are the visualization of the airways, sampling for diagnostic purposes and management of the artificial airways. The decision to perform flexible bronchoscopy can only be made by trade-offs between potential risks and benefits because of the fragile nature of the critically ill. Flexible bronchoscopy-associated serious adverse events are inevitable in cases of a lack of expertise or appropriate precautions.

Management of antithrombotic agents in patients undergoing flexible bronchoscopy

Bleeding is one of the most feared complications of flexible bronchoscopy. Although infrequent, it can be catastrophic and result in fatal outcomes. Compared to other endoscopic procedures, the risk of morbidity and mortality from the bleeding is increased, as even a small amount of blood can fill the tracheobronchial tree and lead to respiratory failure. Patients using antithrombotic agents (ATAs) have higher bleeding risk. A thorough understanding of the different ATAs is critical to manage patients during the peri-procedural period. A decision to stop an ATA before bronchoscopy should take into account a variety of factors, including indication for its use and the type of procedure. This article serves as a detailed review on the different ATAs, their pharmacokinetics and the pre- and post-bronchoscopy management of patients receiving these medications.

Elective intubation and positive pressure ventilation for transbronchial lung biopsy

BACKGROUND

The safety of transbronchial lung biopsy (TBLB) on positive pressure mechanical ventilation has been controversial due to a presumed risk of pneumothorax. Data are especially limited on TBLB with elective intubation and mechanical ventilation. In this study, we compared complications of TBLB in patients who were electively mechanically ventilated for the procedure to those who were not.

MATERIAL AND METHODS

A retrospective review of nonventilator-dependent patients who underwent TBLB in our institution from January 2010 to May 2016 was performed. The mechanical ventilation (MV) and nonmechanical ventilation (NMV) groups were compared with respect to patient demographics, numbers of lobes biopsied (single or multiple), preprocedure and postprocedure diagnoses, and complications. Complications were defined as pneumothorax of any size, major hemorrhage, prolonged intubation, and reintubation within 72 hours from TBLB.

RESULTS

A total of 394 patients were identified. The MV group had 351 patients with mean age of 64.6 years, and the NMV group had 43 patients with mean age of 60.0 years. There were no significant differences with regards to age, gender, or number of lobes biopsied. There was no significant difference in the occurrence of pneumothorax (5.4% versus 4.7%, P = 1.00), hemorrhage (1.7% versus 4.7%, P = 0.21), and prolonged intubation or reintubation (3.1% versus 2.3%, P = 1.00) between the two groups.

CONCLUSIONS

When performing TBLB, there was no significant difference observed in the rate of complications between MV and NMV groups. Elective positive pressure mechanical ventilation for TBLB for nonventilator-dependent patients is safe and does not increase the risk of complications.

Flexible Fiberoptic Bronchoscopy in the Intensive Care Unit

For the past 20 years, flexible fiberoptic bronchoscopy (FOB) has been shown to be an important procedure in the diagnosis and management of patients in intensive care units (ICU). In adults, FOB is used therapeutically to remove retained secretions and to correct atelectasis not improved by conservative means. In the pediatric population, however, FOB is mainly used to diagnose tracheal disease in critically ill children. The principal risks of FOB are hypoxemia and dysrhythmias; hemor rhage and pneumothorax may occur as a result of biopsy procedures. In competent hands, these adverse compli cations of FOB are minimal. Although rigid bronchos copy remains pivotal in most pediatric bronchoscopic procedures, massive hemoptysis, foreign body removal, and laser therapy for occluding tumors of the upper airway, flexible FOB has an increasingly important role in the diagnosis and management of these disorders.

Which patients with ARDS benefit from lung biopsy?

A central tenet of caring for patients with ARDS is to treat the underlying cause, be it sepsis, pneumonia, or removal of an offending toxin. Identifying the risk factor for ARDS has even been proposed as essential to diagnosing ARDS. Not infrequently, however, the precipitant for acute hypoxemic respiratory failure is unclear, and this raises the question of whether a histologic lung diagnosis would benefit the patient. In this review, we consider the historic role of pathology in establishing a diagnosis of ARDS and the published experience of surgical and transbronchial lung biopsy in patients with ARDS. We reflect on which pathologic diagnoses influence treatment and suggest a patient-centric approach to weigh the risks and benefits of a lung biopsy for critically ill patients who may have ARDS.

Invasive diagnostic strategies in immunosuppressed patients with acute respiratory distress syndrome

Immunosuppression predisposes the host to development of pulmonary infections, which can lead to respiratory failure and the development of acute respiratory distress syndrome (ARDS). There are multiple mechanisms by which a host can be immunosuppressed and each is associated with specific infectious pathogens. Early invasive diagnostic modalities such as fiber-optic bronchoscopy with bronchoalveolar lavage, transbronchial biopsy, and open lung biopsy are complementary to serologic and noninvasive studies and assist in rapidly establishing an accurate diagnosis, which allows initiation of appropriate therapy and may improve outcomes with relative safety.

[Diagnostic flexible bronchoscopy. Recommendations of the Endoscopy Working Group of the French Society of Pulmonary Medicine]

These guidelines on flexible bronchoscopy depict important clues to be known and taken into account while practicing flexible bronchoscopy, in adult, except in emergency situations. This is a practical clarification. Safety conditions, complications, anesthesia, infectious risks, cleaning and disinfection are detailed from a review of the literature. Intensive care practice of bronchoscopy requires more attention due to higher risks patients and is discussed extensively. Standards and performances of the various sampling techniques complete this work. Indications for bronchoscopy, therapeutic and paediatric bronchoscopy are not covered in these guidelines.

A contributive result of open-lung biopsy improves survival in acute respiratory distress syndrome patients

OBJECTIVE

The impact of a contributive result of open-lung biopsy on the outcome of patients with acute respiratory distress syndrome (ARDS) has not been extensively investigated. The aim of this study was therefore to determine the rate of contributive open-lung biopsy and whether it improved the prognosis of ARDS patients.

DESIGN

Prospective study conducted during an 8-yr period.

SETTING

A 14-bed medico-surgical intensive care unit and a 12-bed medical intensive care unit from the same hospital.

PATIENTS

One hundred open-lung biopsies were performed in 100 patients presenting ARDS.

INTERVENTIONS

Open-lung biopsy was performed after > or = 5 days of evolution of ARDS when there was no improvement in the respiratory status despite negative microbiological samples cultures and potential indication for corticosteroid treatment.

MEASUREMENTS AND MAIN RESULTS

Ten patients presented a mechanical complication following open-lung biopsy (two pneumothoraces and eight moderate air leaks). The unique independent factor associated with this complication was the minute ventilation when open-lung biopsy was performed (odds ratio, 1.20; 95% confidence interval, 1.03-1.41; p = .02). Fibrosis was noted in 53 patients but was associated with an infection in 29 of these 53 patients (55%). A contributive result of open-lung biopsy (defined as the addition of a new drug) was noted in 78 patients. Simplified Acute Physiology Score II was the only independent predictive factor of a contributive open-lung biopsy (odds ratio, 0.96; 95% confidence interval, 0.92-0.99; p = .04). Survival was higher in patients with a contributive open-lung biopsy (67%) than in patients in whom open-lung biopsy results did not modify the treatment (14%) (p < .001). The factors predicting survival were a contributive result of open-lung biopsy, female gender, and the Organ System Failures score the day of open-lung biopsy.

CONCLUSIONS

The present study shows that open-lung biopsy provided a contributive result in 78% of ARDS patients with a negative bronchoalveolar lavage. Survival of ARDS patients improved when open-lung biopsy was contributive.

Contraindications and safety of transbronchial lung biopsy via flexible bronchoscopy. A survey of pulmonologists and review of the literature

BACKGROUND

Transbronchial lung biopsy (TBLB) via flexible bronchoscopy is a common procedure performed by pulmonologists. Limited scientific data exist concerning the risk of this procedure in patients with conditions that may adversely affect the rate of procedural complications.

OBJECTIVES

To evaluate the current practice pattern and attitude of pulmonologists toward the performance of TBLB in the presence of high-risk conditions.

METHODS

A survey was constructed and distributed at the American College of Chest Physicians annual meeting, held in Philadelphia, USA, in November of 2001.

RESULTS

A total of 227 surveys were distributed with a return of 158 (69.6%). Anticoagulation medications are temporarily held prior to TBLB by the majority of our survey respondents (98.7% for intravenous heparin, 90.5% for warfarin, and 87.3% for low-molecular-weight heparin). Medications with effect on platelet function are held by fewer pulmonologists. There is a wide variation in the pulmonologists' perception of the risk of performing TBLB when certain medical conditions coexist: pulmonary hypertension [absolute contraindication (AC), 28.7%; relative contraindication (RC) 58.6%], superior vena cava syndrome (AC 19.6%, RC 51%), mechanical ventilation (AC 17.8%, RC 58.6%) and lung cavity/abscess (AC 7%, RC 44.9%). A significant percentage of pulmonologists (55%) do not regard an elevated serum creatinine at any level as AC to TBLB. Thirty-eight percent of the survey participants administer desmopressin prior to TBLB in uremic patients to prevent excessive bleeding.

CONCLUSIONS

Prior to performing bronchoscopic TBLB, the majority of pulmonologists temporarily holds anticoagulation medications. However, there is a lack of agreement in relation to perceived contraindications and safety of TBLB.

The pulmonary physician in critical care 1: pulmonary investigations for acute respiratory failure

This is the first in a series of reviews of the role of the pulmonary physician in critical care medicine. The investigation of mechanically ventilated patients is discussed, with particular reference to those presenting with acute respiratory failure and diffuse pulmonary infiltrates.

Role of bronchoscopy in modern medical intensive care unit

This article gives a broad overview of the increasingly important applications of bronchoscopy, flexible (FOB) and rigid (RB), in a modern medical intensive care unit. Special emphasis is made to bronchoscopy use in mechanically ventilated patients. Therapies such as endobronchial stenting and Nd:YAG laser are being used to improve respiratory failure and facilitate weaning from mechanical ventilation. Practical applications of recent advancements in technology (endobronchial stenting, laser therapy, and so forth), the increasing use of rigid bronchoscopy, and the new generation of flexible bronchoscopes like battery bronchoscopes, and ultra-thin bronchoscopes, are also discussed. The risks, potential benefits, complications, and suggested technique of performing bronchoscopy in mechanically ventilated patients are reviewed.

Microbial investigation in ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is a serious infectious condition in intensive care unit (ICU) patients, currently related to a high mortality rate. Therefore, this complication of mechanical ventilation requires a prompt diagnosis and adequate antibiotic treatment. The detection of the causative organism is imperative for guiding an appropriate therapy as there is strong evidence of the adverse effect of inadequate empirical treatment on outcome. The major difficulty of the microbial investigation is to obtain the sample from the lower respiratory tract, mainly because of the potential contamination with upper airways flora, which may result in a misinterpretation of the cultures. Microbial investigation in VAP is based on the culture of samples obtained from lower respiratory tract by noninvasive or invasive methods. The most common techniques of sampling are the endotracheal aspirate (ETA), which is considered a noninvasive method, the protected specimen brush (PSB) and the bronchoalveolar lavage (BAL), both being invasive methods of investigation. The latter were designed as an attempt to avoid the colonizing flora of the upper airways. The best of these diagnostic approaches is still controversial. In terms of outcome, there is strong evidence that the impact of both invasive and noninvasive methods seems to be similar. In terms of cost, however, the endotracheal aspirate is less expensive compared to BAL or PSB. On the other hand, invasive methods could be particularly beneficial in patients who are not responding to the initial empirical antibiotic treatment. The rationale for the quantitative culture of the respiratory samples is to differentiate between infection and colonization of lower airways, because the bacterial colonization is a frequent event in mechanically ventilated patients. The thresholds currently employed for the diagnosis of the pneumonia are the following: ETA samples, > or = 10(5)-10(6) colony forming units (cfu).mL(-1); PSB samples, > or =10(3) cfu.mL(-1); and BAL samples, > or =10(4) cfu.mL(-1). Intending to provide a practical approach to the issue, the present manuscript reviews the available noninvasive (blood culture, endotracheal aspirate) and invasive (protected specimen brush, bronchoalveolar lavage, blinded methods and lung biopsy) techniques used for the diagnosis of ventilator-associated pneumonia.

Invasive diagnostic techniques for pneumonia: protected specimen brush, bronchoalveolar lavage, and lung biopsy methods

We suggest the following strategy for managing patients with pneumonia. For nonventilated patients with either CAP or HAP, empiric antibiotic treatment should be started according to approved guidelines, and if the clinical evolution of the patient is not adequate, fiberoptic bronchoscopy including PSB and BAL could be considered, with modification of the antibiotic treatment accordingly. In ventilated patients with either CAP or HAP, respiratory secretion sampling using noninvasive techniques should be conducted upon clinical suspicion of VAP and before starting a new antibiotic treatment. Antibiotic therapy according to approved guidelines should be started as soon as possible and maintained during the first 48 hours if the patient's evolution is satisfactory and condition has stabilized. Then, initial antibiotic treatment should be adjusted according to cultures. If there is a clear diagnostic alternative to VAP and cultures are negative, this is the only case in which antibiotic treatment could be withdrawn. If the patient's clinical evolution is inadequate (persistence of fever, leukocytosis, increasing infiltrates, and respiratory failure), fiberoptic bronchoscopy with PSB and BAL and modification of the initial antibiotic regimen should be sought. Open lung biopsy may be indicated in patients with diffuse pulmonary infiltrates in whom a diagnosis has not been achieved by other methods, including bronchoscopy. Transbronchial lung biopsy should not be viewed as a diagnostic technique for pneumonia except in immunosuppressed patients with diffuse alveolar infiltrates.

Utility of transbronchial biopsy in patients with acute respiratory failure: a postmortem study

STUDY OBJECTIVE

To determine the diagnostic yield of histologic specimens obtained by postmortem transbronchial biopsy (TBB) in patients with acute respiratory failure requiring mechanical ventilation.

DESIGN

Standard postmortem histologic examination of lung tissue specimens.

SETTING

An urban university-affiliated hospital.

PATIENTS OR PARTICIPANTS

Thirty patients with diffuse pulmonary infiltrates and acute respiratory failure, who underwent postmortem examination.

INTERVENTIONS

Following removal of the lungs from the thorax. TBBs were obtained from the lower lobe of each deflated lung and comparison was made to a 1-cm3 tissue block obtained from the ipsilateral lower lobe.

MEASUREMENTS AND RESULTS

Standard postmortem histologic examination provided a specific diagnosis in 85% of the 60 lungs examined, and histologic evidence of acute pneumonia was present in 30% of the lungs. The overall yield of TBB was 48% for establishing a specific histologic diagnosis and 15% for the diagnosis of acute pneumonia. Using standard postmortem histologic examination as the gold standard, the sensitivity and specificity of TBB for making a specific diagnosis were 57% and 100% respectively, with corresponding positive and negative predictive values of 100% and 29%. For the histologic diagnosis of acute pneumonia, the sensitivity of TBB was 50%, the specificity was 100%, and the positive and negative predictive values were 100% and 82%, respectively. The kappa statistic for the agreement between the two diagnostic methods was 0.28 for establishing a specific diagnosis and 0.58 for the diagnosis of acute pneumonia. Obtaining 12 TBBs rather than six TBBs did not increase the diagnostic yield for TBB.

CONCLUSIONS

These findings suggest poor overall agreement between standard postmortem histologic examination and TBB specimens. Although not performed in a clinical setting, this postmortem investigation suggests that TBB may be of limited value in mechanically ventilated patients with acute respiratory failure because of its low sensitivity.

Safety and yield of transbronchial biopsy in mechanically ventilated patients

OBJECTIVE

To evaluate the safety and diagnostic yield of transbronchial biopsy performed in mechanically ventilated patients.

DESIGN

Retrospective, cohort analysis.

SETTING

A university-affiliated teaching hospital.

PATIENTS

Seventy-one consecutive, mechanically ventilated patients requiring lung tissue examination.

INTERVENTIONS

Transbronchial lung biopsy.

MEASUREMENTS AND MAIN RESULTS

We evaluated complications associated with transbronchial biopsy, diagnostic yield of the procedure, and changes in patient management based on the results of the transbronchial lung biopsies. Eighty-three transbronchial lung biopsy procedures were performed in this patient cohort. Complications associated with these procedures included the following: ten (14.3%) pneumothoraces in patients without preexisting chest tubes; five (6.0%) episodes of bronchial hemorrhage of > 30 mL; transient oxygen desaturation to < 90% in seven (8.4%) patients; hypotension with a mean arterial pressure of < 60 mm Hg in six (7.2%) patients; and three (3.6%) episodes of tachycardia, with a heart rate of > 140 beats/min. No patient deaths, episodes of pneumonia, or sepsis could be attributed to the transbronchial lung biopsy procedures. Specific histologic diagnoses were made with 29 (34.9%) of the transbronchial biopsies, and patient management was changed as a direct result of the lung tissue examination in 34 (41.0%) instances. Pathologic correlation between the transbronchial biopsy specimens and lung tissue obtained by open-lung biopsy or post mortem examination occurred in 11 (84.6%) of 13 paired samples.

CONCLUSION

Transbronchial lung biopsy can be performed with an acceptable risk and reasonable diagnostic yield in certain types of mechanically ventilated patients, often obviating the need to perform open-lung biopsy.

Pulmonary fibrosis correlates with outcome in adult respiratory distress syndrome. A study in mechanically ventilated patients

STUDY OBJECTIVE

The present study was carried out to evaluate the prognostic value of pulmonary fibrosis diagnosed on the basis of pulmonary samples obtained by fiberscopic transbronchial lung biopsy (TBLB) in patients treated for severe established adult respiratory distress syndrome (ARDS).

DESIGN

Prospective cohort study.

SETTING

Intensive Care Unit of a University Hospital.

PATIENTS

Consecutive patients with a diagnosis of established ARDS.

INTERVENTIONS

Samples of pulmonary tissue (3 to 6 in each patient) were obtained by fiberoptic TBLB. Severity of pulmonary fibrosis was assessed based on pathologic changes. Hematoxylin and eosin and Masson's trichrome stains were performed on each tissue sample.

MAIN RESULTS

Twenty-two lung specimens were obtained from 25 consecutive patients with ARDS of various origin (postsurgical complications, 7 patients; multiple trauma, 8 patients; medical problems, 7 patients). Transbronchial lung biopsy was complicated by small or moderate hemorrhage in three patients. No case of pneumothorax was identified. Pathologic findings showed that 14 patients (64%) had pulmonary fibrosis, either mild (9 patients) or moderate to severe fibrosis (5 patients). In the patients with pulmonary fibrosis, mortality rate was 57% (8 out of 14 patients), which was significantly different (p < 0.02) from the 0% mortality rate observed in patients without pulmonary fibrosis. Severity of pulmonary fibrosis (mild vs moderate and severe) did not influence outcome. With the exception of pathologic findings, characteristics of patients with and without pulmonary fibrosis (PaO2, PaCO2, the ratio of PaO2 to fraction of inspired oxygen, and positive end-expiratory pressure) were not different.

CONCLUSION

In the study patients, pulmonary fibrosis diagnosed on the basis of TBLB was closely related to fatality in established ARDS.

Fibreoptic bronchoscopy in the critically ill: a prospective study of its diagnostic and therapeutic value

AIM

A prospective study was undertaken to assess the diagnostic value and therapeutic usefulness of fibreoptic bronchoscopy in the critically ill.

METHOD

Fifty-six bronchoscopies were performed in fifty patients. Biochemical, radiological, microbiological and clinical assessments were made before and after each procedure.

RESULTS

Eighteen fibreoptic bronchoscopies were performed for therapeutic indications (32.1%) of which ten (55.6%) yielded a useful outcome. Thirty-eight bronchoscopies were for diagnostic purposes (67.8%) of which 22 (57.9%) were clinically useful. Broncho-alveolar lavage was performed in twenty-eight cases (50%) and it led to a clinically useful diagnosis in 17 (60.7%). There was no major complication. A subgroup of patients was defined (persistent left lower lobe collapse or consolidation following thoracic or abdominal surgery) in whom fibreoptic bronchoscopy usually did not yield a useful outcome.

CONCLUSION

The use of fibreoptic bronchoscopy in the Intensive Care Unit, in combination with the technique of broncho-alveolar lavage, results in a clinically useful outcome in the majority of cases. Fibreoptic bronchoscopy is an effective and safe diagnostic and therapeutic tool in critically ill patients.

Pediatric transbronchial lung biopsy

A retrospective review of 25 transbronchial lung biopsies in 19 pediatric patients is reported. Nineteen of these procedures used a rigid ventilating bronchoscope and a small cup biopsy forceps. The indications included diffuse pulmonary infiltrates in the immunocompromised patient, severe hyaline membrane disease, tumor, and lung transplant. In 84% of the procedures, adequate tissue was obtained. There was a 12.5% incidence of pneumothorax and no significant pulmonary hemorrhage.

Bronchoscopy in the intensive care unit

The development of the flexible, fiberoptic bronchoscope has made bronchoscopic examinations possible in ICU patients undergoing mechanical ventilation. Over the years, the number of such procedures has greatly increased, with both diagnostic and therapeutic objectives, such as performing difficult intubation, management of atelectasis and hemoptysis, diagnosis of nosocomial pneumonia in ventilated patients, and early detection of airway lesions in selected situations, such as high-frequency ventilation. The complication rate can be kept low if the endoscopist has a precise knowledge of the many pathophysiological and technical facets particular to bronchoscopy under these difficult conditions. This article reviews some of these aspects, in the light of our personal experience.

Bronchoscopy in the critical-care unit

To determine the diagnostic and therapeutic usefulness as well as safety of flexible fiberoptic bronchoscopy (FFB) in patients admitted to the critical-care unit (CCU), we conducted a review of all such procedures done in our CCU from 1985 to 1988. A total of 129 patients underwent 198 FFB, of which 76% were in mechanically ventilated patients. FFB was done for diagnostic purposes in 87, for therapeutic purposes in 93, and for both reasons in 18. Of the 71 diagnostic FFB performed for cultures, 27 (38%) were positive but only 18 (25%) influenced patient management. An additional 25 FFB were helpful in making therapeutic decisions even though the cultures were negative. Ten of 13 FFB performed for evaluation of airways and 1 of 3 done for hemoptysis were helpful. Of the 90 FFB done because of retained secretions, 37 (41%) showed mucous plugs or significant secretions, but clinical improvement was noted in only 17 (19%). Overall, FFB contributed substantially to patient management in 82 of the 198 procedures (41%). Seven patients had transient complications, but no deaths occurred. We conclude that FFB is safe and can be helpful in the CCU setting.

A new diagnostic approach to the patient with severe pneumonia

36 patients with severe community-acquired pneumonia, treated in an intensive care unit (ICU), were examined in a prospective study using a comprehensive diagnostic program to establish an early etiological diagnosis. The resulting prompt and adequate antimicrobial therapy may have decreased the number of fatal cases. Special emphasis was placed on the use of a method incorporating fiberoptic bronchoscopy, together with protected brush sampling and bronchial lavage. An etiological diagnosis was established in 81% (29/36) of the cases. This etiological diagnosis was established within 48-72 h in 53% (19/36) of the patients, S. pneumoniae being the most frequent agent found (12 patients). This information, however, was poorly utilized since in only 11/19 of these patients was the antimicrobial therapy changed from a broad-spectrum antibiotic to a more specific narrow spectrum agent. The overall mortality rate was 22% (8/36). 7/8 patients who died had compromising factors. Most deaths in community-acquired pneumonia are still associated with pneumococcal infection. We conclude that fiberoptic bronchoscopy with brush samples via a plugged double lumen catheter provides the least misleading information concerning the etiological agent in pneumonia; sampling should be done as soon as possible after admission to the hospital, ideally before the need for ICU treatment; factors other than prompt antimicrobial therapy may influence the outcome of severe community-acquired pneumonia.