Bronchoscopy in the intensive care unit

Early bronchoscopy in severe pneumonia patients in intensive care unit: insights from the Medical Information Mart for Intensive Care-IV database analysis

BACKGROUND

Pneumonia frequently leads to intensive care unit (ICU) admission and is associated with a high mortality risk. This study aimed to assess the impact of early bronchoscopy administered within 3 days of ICU admission on mortality in patients with pneumonia using the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database.

METHODS

A single-center retrospective analysis was conducted using the MIMIC-IV data from 2008 to 2019. Adult ICU-admitted patients diagnosed with pneumonia were included in this study. The patients were stratified into two cohorts based on whether they underwent early bronchoscopy. The primary outcome was the 28-day mortality rate. Propensity score matching was used to balance confounding variables.

RESULTS

In total, 8,916 patients with pneumonia were included in the analysis. Among them, 783 patients underwent early bronchoscopy within 3 days of ICU admission, whereas 8,133 patients did not undergo early bronchoscopy. The primary outcome of the 28-day mortality between two groups had no significant difference even after propensity matched cohorts (22.7% vs. 24.0%, P=0.589). Patients undergoing early bronchoscopy had prolonged ICU (P<0.001) and hospital stays (P<0.001) and were less likely to be discharged to home (P<0.001).

CONCLUSIONS

Early bronchoscopy in severe pneumonia patients in the ICU did not reduce mortality but was associated with longer hospital stays, suggesting it was used in more severe cases. Therefore, when considering bronchoscopy for these patients, it's important to tailor the decision to each individual case, thoughtfully balancing the possible advantages with the related risks.

Bronchoscopy in Patients With Known or Suspected COVID-19: Results From the Global Pandemic SARS-CoV-2 Bronchoscopy Database (GPS-BD)

BACKGROUND

Amid the Coronavirus Disease 2019 (COVID-19) pandemic, the benefits and risks of bronchoscopy remain uncertain. This study was designed to characterize bronchoscopy-related practice patterns, diagnostic yields, and adverse events involving patients with known or suspected COVID-19.

METHODS

An online survey tool retrospectively queried bronchoscopists about their experiences with patients with known or suspected COVID-19 between March 20 and August 20, 2020. Collected data comprised the Global Pandemic SARS-CoV-2 Bronchoscopy Database (GPS-BD). All bronchoscopists and patients were anonymous with no direct investigator-to-respondent contact.

RESULTS

Bronchoscopy procedures involving 289 patients from 26 countries were analyzed. One-half of patients had known COVID-19. Most (82%) had at least 1 pre-existing comorbidity, 80% had at least 1 organ failure, 51% were critically ill, and 37% were intubated at the time of the procedure. Bronchoscopy was performed with diagnostic intent in 166 (57%) patients, yielding a diagnosis in 86 (52%). and management changes in 80 (48%). Bronchoscopy was performed with therapeutic intent in 71 (25%) patients, mostly for secretion clearance (87%). Complications attributed to bronchoscopy or significant clinical decline within 12 hours of the procedure occurred in 24 (8%) cases, with 1 death.

CONCLUSION

Results from this international database provide a widely generalizable characterization of the benefits and risks of bronchoscopy in patients with known or suspected COVID-19. Bronchoscopy in this setting has reasonable clinical benefit, with diagnosis and/or management change resulting from about half of the diagnostic cases. However, it is not without risk, especially in patients with limited physiological reserve.

Indications, Clinical Utility, and Safety of Bronchoscopy in COVID-19

BACKGROUND

Bronchoscopy is an aerosol-generating procedure and routine use for patients with coronavirus disease 2019 (COVID-19) has been discouraged. The purpose of this review was to discuss the indications, clinical utility, and risks associated with bronchoscopy in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia.

METHODS

A literature search was performed by using appropriate key terms to identify all relevant articles from medical literature databases up to August 1, 2021.

RESULTS

Twelve cohorts (9 retrospective and 3 prospective) reported the performance of 2,245 bronchoscopies in 1,345 patients with COVID-19. The majority of the subjects were male. Nearly two thirds of the bronchoscopies (62%) were performed for therapeutic indications; the rest (38%) were for diagnostic purposes. Bronchoalveolar lavage had an overall yield of 33.1% for SARS-CoV-2 in subjects with negative results of real-time polymerase chain reaction on nasopharyngeal specimens. The incidence of a secondary infection ranged from 9.3% to as high as 65%. Antibiotics were changed in a significant number of the subjects (14%-83%) based on the bronchoscopic findings. Bronchoscopy was well tolerated in most subjects except those who required noninvasive ventilation, in whom the intubation rate after the procedure was 60%. The rate of transmission of SARS-CoV-2 among health-care workers was minimum.

CONCLUSIONS

Bronchoscopy in patients with COVID-19 results in a significant change in patient management. Transmission of SARS-CoV-2 seems to be low with consistent use of appropriate personal protective equipment by health-care workers. Therefore, bronchoscopic evaluation should be considered for all diagnostic and therapeutic indications in this patient population.

Noninvasive Ventilation-assisted Bronchoscopy in High-risk Hypoxemic Patients

BACKGROUND AND AIMS

Hypoxemic patients undergoing fiber-optic bronchoscopy (FOB) are at risk of worsening of respiratory failure requiring mechanical ventilation due to FOB procedure itself and its complications. As patients with respiratory failure are frequently managed by non-invasive ventilation (NIV); feasibility of FOB through NIV mask has been evaluated in some studies to avoid intubation. We describe here our own case series.

MATERIALS AND METHODS

Clinical data of 28 FOB done through NIV mask in 27 intensive care unit (ICU) patients over 6 years period at our center was collected retrospectively and analysed.

RESULTS

Study comprises 27 (17 male; 52±21.6 years age) hypoxemic (PaO2 71.3±14.2, on NIV and oxygen supplementation) patients. All FOB were done at bedside, 15 of them were given sedation for the procedure. Twenty four patients had bronchoalveolar lavage (BAL); three underwent bronchial biopsies, four brush cytology and seven transbronchial biopsies. In 10 patients lung or lobar collapse was reversed. There was no significant change between pre and post bronchoscopy ABG parameters except for improved post FOB PaO2 (p = 0.0032) and SpO2 (p = 0.0046). One patient (3.57%) developed late pneumothorax and 3 patients (10.7%) had bleeding after biopsy. Prior to bronchoscopy 17 (16 BIPAP, 1 CPAP) patients were already on NIV. Two patients required mechanical ventilation 6 hours after FOB due to subsequent clinical deterioration but could be weaned off later. One patient died on third day after FOB from acute myocardial infarction.

CONCLUSION

Hypoxemic patients in ICU can safely undergo bedside diagnostic and simple therapeutic bronchoscopy with NIV support while mostly avoiding intubation and with low complication rates.

HOW TO CITE THIS ARTICLE

Sircar M, Jha OK, Chabbra GS, Bhattacharya S. Noninvasive Ventilation-assisted Bronchoscopy in High-risk Hypoxemic Patients. Indian J Crit Care Med 2019;23(8):363-367.

Effect of Bronchoscopy on Gas Exchange and Respiratory Mechanics in Critically Ill Patients With Atelectasis: An Observational Cohort Study

Background: Atelectasis frequently develops in critically ill patients and may result in impaired gas exchange among other complications. The long-term effects of bronchoscopy on gas exchange and the effects on respiratory mechanics are largely unknown.

Objective: To evaluate the effect of bronchoscopy on gas exchange and respiratory mechanics in intensive care unit (ICU) patients with atelectasis.

Methods: A retrospective, single-center cohort study of patients with clinical indication for bronchoscopy because of atelectasis diagnosed on chest X-ray (CXR).

Results: In total, 101 bronchoscopies were performed in 88 ICU patients. Bronchoscopy improved oxygenation (defined as an increase of PaO₂/FiO₂ ratio > 20 mmHg) and ventilation (defined as a decrease of > 2 mmHg in partial pressure of CO₂ in arterial blood) in 76 and 59% of procedures, respectively, for at least 24 h. Patients with a low baseline value of PaO₂/FiO₂ ratio and a high baseline value of PaCO₂ were most likely to benefit from bronchoscopy. In addition, in intubated and pressure control ventilated patients, respiratory mechanics improved after bronchoscopy for up to 24 h. Mild complications, and in particular desaturation between 80 and 90%, were reported in 13% of the patients.

Conclusions: In selected critically ill patients with atelectasis, bronchoscopy improves oxygenation, ventilation, and respiratory mechanics for at least 24 h.

Comparison between traditional and small-diameter tube-assisted bronchoscopic balloon dilatation in the treatment of benign tracheal stenosis

OBJECTIVE

To compare the safety and efficacy between using a small-diameter tube-assisted bronchoscopic balloon dilatation (BBD) and the traditional BBD in the treatment of benign tracheal stenosis.

METHODS

A retrospective study included 58 patients with benign tracheal stenosis from August 2009 to December 2014 was made. The patients who underwent traditional BBD were divided into group A, and who underwent a small-diameter tube-assisted BBD were divided into group B. The tracheal diameter, dyspnea index and blood gas analysis results were detected before and after BBD. Efficacy and complications were evaluated after BBD.

RESULTS

There were significant differences in oxygen saturation (PaO₂ ) during the operations comparing with before and after operations in group A (P = .005), while there was no significant difference in group B (P = .079). The tracheal diameter obviously increased (in group A, from 4.16 ± 1.43 mm to 12.47 ± 1.41 mm, P = .000; in group B: from 4.94 ± 1.59 mm to 12.61 ± 1.41 mm, P = .000). Dyspnea index obviously decreased (group A: from 3.21 ± 0.93 to 0.50 ± 0.59, P = .000; group B: from 3.24 ± 0.89 to 0.65 ± 0.69, P = .000). The immediately cure rate in both groups was 100%. Long-term effect was significantly better in group B than that in group A (85.3% vs 59.1%, P = .021), at the end of the follow-up period.

CONCLUSIONS

Small-diameter tube-assisted BBD obtains better safety and long-term efficacy than the traditional BBD in the treatment of benign tracheal stenosis. However, close attention should be given to the risk of the adverse effects caused by carbon dioxide retention.

Management of Benign Tracheal Stenosis by Small-diameter Tube-assisted Bronchoscopic Balloon Dilatation

Background:

A limitation of bronchoscopic balloon dilatation (BBD) is that airflow must be completely blocked for as long as possible during the operation. However, the patient often cannot hold his or her breath for a long period affecting the efficacy of the procedure. In this study, we used an extra-small-diameter tube to provide assisted ventilation to patients undergoing BBD and assessed the efficacy and safety of this technique.

Methods:

Bronchoscopic balloon dilatation was performed in 26 patients with benign tracheal stenosis using an extra-small-diameter tube. The tracheal diameter, dyspnea index, blood gas analysis results, and complications were evaluated before and after BBD. Statistical analyses were performed by SPSS version 16.0 for Windows (SPSS, Inc., Chicago, IL, USA).

Results:

Sixty-three BBD procedures were performed in 26 patients. Dyspnea immediately improved in all patients after BBD. The tracheal diameter significantly increased from 5.5 ± 1.5 mm to 13.0 ± 1.3 mm (P < 0.001), and the dyspnea index significantly decreased from 3.4 ± 0.8 to 0.5 ± 0.6 (P < 0.001). There was no significant change in the partial pressure of oxygen during the operation (before, 102.5 ± 27.5 mmHg; during, 96.9 ± 30.4 mmHg; and after, 97.2 ± 21.5 mmHg; P = 0.364), but there was slight temporary retention of carbon dioxide during the operation (before, 43.5 ± 4.2 mmHg; during, 49.4 ± 6.8 mmHg; and after, 40.1 ± 3.9 mmHg; P < 0.001).

Conclusion:

Small-diameter tube-assisted BBD is an effective and safe method for the management of benign tracheal stenosis.

Resident Self-Assessment and Learning Goal Development: Evaluation of Resident-Reported Competence and Future Goals

OBJECTIVE

To determine incidence of learning goals by competency area and to assess which goals fall into competency areas with lower self-assessment scores.

METHODS

Cross-sectional analysis of existing deidentified American Academy of Pediatrics' PediaLink individualized learning plan data for the academic year 2009-2010. Residents self-assessed competencies in the 6 Accreditation Council for Graduate Medical Education (ACGME) competency areas and wrote learning goals. Textual responses for goals were mapped to 6 ACGME competency areas, future practice, or personal attributes. Adjusted mean differences and associations were estimated using multiple linear and logistic regression.

RESULTS

A total of 2254 residents reported 6078 goals. Residents self-assessed their systems-based practice (51.8) and medical knowledge (53.0) competencies lowest and professionalism (68.9) and interpersonal and communication skills (62.2) highest. Residents were most likely to identify goals involving medical knowledge (70.5%) and patient care (50.5%) and least likely to write goals on systems-based practice (11.0%) and professionalism (6.9%). In logistic regression analysis adjusting for postgraduate year (PGY), gender, and degree type (MD/DO), resident-reported goal area showed no association with the learner's relative self-assessment score for that competency area. In the conditional logistic regression analysis, with each learner serving as his or her own control, senior residents (PGY2/3+s) who rated themselves relatively lower in a competency area were more likely to write a learning goal in that area than were PGY1s.

CONCLUSIONS

Senior residents appear to develop better skills and/or motivation to explicitly turn self-assessed learning gaps into learning goals, suggesting that individualized learning plans may help improve self-regulated learning during residency.

Impact of bedside bronchoscopy in critically ill lung transplant recipients

BACKGROUND

Over 32,000 lung transplants have been performed worldwide for a variety of end-stage lung diseases (http://www.ishlt.org/). Flexible bronchoscopy (FB) is frequently used as a bedside-tool for diagnosis and management of respiratory failure among critically ill lung transplant recipients (LTRs). We study the indications, results, therapeutic impact, and complications of FB in LTRs admitted to medical intensive care unit (MICU).

METHODS

Retrospective chart review was performed for all critically ill LTRs undergoing FB while admitted to MICU at the Cleveland Clinic Foundation between 2009 and 2011. ICD-9 codes for bronchoscopy were used to identify patients. The procedures were categorized as: (i) airway examination and interventions, (ii) microbiological, and (iii) histopathologic diagnosis. SAS version 9.2 was used for analysis.

RESULTS

A cohort of 76 LTRs accounted for 93 hospital admissions, 101 MICU admissions, and 129 bronchoscopies. FB was helpful in evaluation and management of airway complications [secretion clearance (18% bronchoscopy procedures), stenosis/dehiscence (8% patients)] and optimizing management of lower respiratory tract infections. Isolation of resistant gram-negative organisms, community-acquired respiratory viruses, and fungi commonly led to modification in antimicrobial therapy (35% microbiological samples). Nonspecific finding of acute lung injury was the most commonly seen histopathology (70%) on transbronchial biopsy. Twenty percent (4/20) of transbronchial biopsies showed acute cellular rejection, with 1 episode contributing to respiratory failure. Occasional hypoxia and hypotension, but no deaths, were noted due to FB during the ICU admission.

CONCLUSIONS

Use of FB modified clinical management in one third of airway evaluation and microbiological sampling procedures for critically ill LTRs. No fatalities were attributed to bronchoscopy in this critically ill population.

Role of bronchoscopy during non invasive ventilation in hypercapnic respiratory failure

Introduction

Non invasive positive pressure ventilation (NIPPV) is the first line treatment for hypercapnic acute respiratory failure (ARF) secondary to COPD exacerbation in selected patients. Limited data exist supporting the use of fiberoptic bronchoscopy (FOB) during this clinical setting. The aim of this study is to assess the role of FOB during NIPPV in patients with decompensated COPD acute exacerbation.

Methods

This study is a randomized prospective case control pilot study carried out on 50 patients - admitted to critical care units at Alexandria University Hospital, Egypt - suffering from hypercapnic ARF secondary to COPD exacerbation with Kelly Matthay Score from 2 to 4. All patients received NIPPV. Patients were divided randomly into 2 equal groups: group I (cases) (25 patients) was subjected to additional intervention of early FOB during the first 6–12 h from admission while group II (control) (25 patients) received the conventional treatment and NIPPV only. Outcome parameters measured were changes in ABG data, duration of NIPPV, rate of its success, ICU stay and mortality as well as the safety of FOB and possible complications.

Results

No significant difference was detected between the 2 groups regarding the baseline characteristics. No serious complications happened from FOB, and Oxygen desaturation happened in 4/25 patients (16%), Tachycardia in 2/25 patients (8%). In group I, 23 patients (92%) were successfully weaned from NIPPV versus 16 patients (64%) in group II (p = 0.037). Total duration of NIPPV was 28.52 h in group I versus 56.25 h in group II (p = 0.001). Length of ICU stay was 4.84 days in group I versus 8.68 days in group II (p = 0.001). Only 1 patient died in group I versus 3 patients in group II (p = 0.609).

Conclusion

The early application of FOB during NIPPV in patients with ARF due to COPD exacerbation was shown to be safe. Significant improvement in the outcome of patients who underwent FOB was noticed in terms of improved ABG data, shorter duration of NIPPV, higher percentage of success and shorter ICU stay while no significant difference was detected in mortality.

Safety of performing fiberoptic bronchoscopy in critically ill hypoxemic patients with acute respiratory failure

BACKGROUND

The safety of fiberoptic bronchoscopy (FOB) in nonintubated critically ill patients with acute respiratory failure has not been extensively evaluated. We aimed to measure the incidence of intubation and the need to increase ventilatory support following FOB and to identify predictive factors for this event.

METHODS

A prospective multicenter observational study was carried out in eight French adult intensive care units. The study included 169 FOB performed in patients with a PaO(2)/FiO(2) ratio ≤ 300. The main end-point was intubation rate. The secondary end-point was rate of increased ventilatory support defined as an increase in oxygen requirement >50 %, the need to start noninvasive positive pressure ventilation (NI-PPV) or increase NI-PPV support.

RESULTS

Within 24 h, an increase in ventilatory support was required following 59 bronchoscopies (35 %), of which 25 (15 %) led to endotracheal intubation. The existence of chronic obstructive pulmonary disease (COPD; OR 5.2, 95 % CI 1.6-17.8; p = 0.007) or immunosuppression (OR 5.4, 95 % CI 1.7-17.2; p = 0.004] were significantly associated with the need for intubation in the multivariable analysis. None of the baseline physiological parameters including the PaO(2)/FiO(2) ratio was associated with intubation.

CONCLUSIONS

Bronchoscopy is often followed by an increase in ventilatory support in hypoxemic critically ill patients, but less frequently by the need for intubation. COPD and immunosuppression are associated with the need for invasive ventilation in the 24 h following bronchoscopy.

Effects on respiratory mechanics of bronchoalveolar lavage in mechanically ventilated patients

INTRODUCTION

Inconsistent findings have been reported about the effects of bronchoalveolar lavage (BAL) on respiratory mechanics. The aims of this study were to study the effects of BAL on respiratory mechanics in mechanically ventilated patients with suspected pneumonia and to find out whether these effects are related to the extension of radiographic infiltrate and preceding respiratory mechanics measurements.

METHODS

Bronchoscopy BAL was performed with 150 mL of sterile isotonic saline in 3 aliquots of 50 mL. Respiratory mechanics parameters were measured by the rapid airway occlusion technique, immediately before and after BAL and 90 minutes later. Patients were classified according to unilateral or bilateral radiological infiltrate occurrence.

RESULTS

Fifty critically ill patients undergoing mechanical ventilation were included. Respiratory system compliance (Crs) decreased from 43.32±13.17 mL/cm H2O to 33.02±9.56 mL/cm H2O (P<0.01) and airway resistance increased from 15.16±7.04 cm H2O/L/s to 17.54±9.40 cm H2O/L/s (P<0.05) immediately after BAL; 90 minutes later both the parameters returned to the pre-BAL values. Patients who showed a greater than 20% decrease in Crs had a higher pre-BAL Crs than patients with a less severe decrease (49.85±10.7 mL/cm H2O vs. 35.65±11.67 mL/cm H2O; P<0.01). However, neither pre-BAL airway resistance nor the extension of the radiographic infiltrates was related to the changes in respiratory mechanics.

CONCLUSIONS

BAL in mechanically ventilated patients can lead to a significant, although transitory, deterioration in pulmonary mechanics, characterized by a decrease in Crs and by an increase in airway resistance. Patients with better initial Crs showed the most severe affectation.

[Current status of fibreoptic bronchoscopy in intensive care medicine]

Flexible bronchoscopy (FB) has been of great help in the management of critically ill patients. Its safety and usefulness in the hands of experienced professionals, with the required measures of caution, has resulted in the increasingly widespread use of the technique even in unstable critical patients subjected to mechanical ventilation and with high oxygen demands. The Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC), through its Acute Respiratory Failure (GT-IRA) and Infectious Diseases (GT-EI) Work Groups, aims to promote knowledge and standards of quality in the use of FB among all specialists in Intensive Care Medicine. Through an expert committee, the SEMICYUC has established the objective of accrediting such training, with the preparation of a curriculum and definition of those Units qualified for providing training in the different techniques and levels. The accreditation process seeks to stimulate good learning practice and quality in training. Both specialists in Intensive Care Medicine and other specialists, and the patients, will benefit from the commitment and control afforded by such accreditation, and from the learning and training which the mentioned process entails.

Fiberoptic bronchoscopy for the rapid diagnosis of smear-negative pulmonary tuberculosis

Background

This study was aimed to investigate the diagnostic value of fiberoptic bronchoscopy (FOB) with chest high-resolution computed tomography (HRCT) for the rapid diagnosis of active pulmonary tuberculosis (PTB) in patients suspected of PTB but found to have a negative sputum acid-fast bacilli (AFB) smear.

Methods

We evaluated the diagnostic accuracy of results from FOB and HRCT in 126 patients at Gangnam Severance Hospital (Seoul, Korea) who were suspected of having PTB.

Results

Of 126 patients who had negative sputum AFB smears but were suspected of having PTB, 54 patients were confirmed as having active PTB. Hemoptysis was negatively correlated with active PTB. Tree-in-bud appearance on HRCT was significantly associated with active PTB. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FOB alone was 75.9%, 97.2%, 95.3%, and 84.3%, respectively, for the rapid diagnosis of active PTB. The combination of FOB and HRCT improved the sensitivity to 96.3% and the NPV to 96.2%.

Conclusions

FOB is a useful tool in the rapid diagnosis of active PTB with a high sensitivity, specificity, PPV and NPV in sputum smear-negative PTB-suspected patients. HRCT improves the sensitivity of FOB when used in combination with FOB in sputum smear-negative patients suspected of having PTB.

[Analysis of 208 flexible bronchoscopies performed in an intensive care unit]

OBJECTIVE

To describe the main indications, clinical results and complications associated with fibrobronchoscopy in the Intensive Care Unit (ICU).

DESIGN

A retrospective, single-center observational study was carried out. Setting. Seventeen beds in a medical/surgical ICU. Patients. Consecutive patients undergoing fibrobronchoscopy during their stay in the ICU over a period of 5 years.

INTERVENTIONS

Flexible bronchoscopy performed by an intensivist. Main variables of interest. Flexible bronchoscopy indications and complications derived from the procedure.

RESULTS

A total of 208 flexible bronchoscopies were carried out in 192 patients admitted to the ICU. Most of the procedures (193 [92.8%]) were performed in mechanically ventilated patients. The average patient age was 58 ± 16 years, with an APACHE II score at admission of 19 ± 7. The most frequent indication for flexible bronchoscopy was diagnostic confirmation of initially suspected pneumonia (148 procedures), with positive bronchoalveolar lavage findings in 46%. The most frequent therapeutic indication was the resolution of atelectasis (28 procedures). Other indications were the diagnosis and treatment of pulmonary hemorrhage, the aspiration of secretions, control of percutaneous tracheotomy, and difficult airway management. The complications described during the procedures were supraventricular tachycardia (3.8%), transient hypoxemia (6.7%), and slight bleeding of the bronchial mucosal membrane (2.4%).

CONCLUSIONS

A microbiological diagnosis of pneumonia and the resolution of atelectasis are the most frequent indications for flexible bronchoscopy in critically ill patients. Flexible bronchoscopy performed by an intensivist in ICU is a safe procedure.

Usefulness of quantitative endotracheal aspirate cultures in intensive care unit patients with suspected pneumonia

It is difficult to differentiate pathogens responsible for pneumonia or colonization in patients with an endotracheal tube or in patients that have undergone tracheostomy. We evaluated the clinical usefulness of quantitative endotracheal aspirates cultures and sought to determine the result threshold level for positivity. The authors performed this retrospective cohort study between December 1, 2004 and January 31, 2006. Forty-five suspected pneumonia patients admitted to an intensive care unit (ICU) with quantitative bronchoalveolar lavage (BAL) and endotracheal aspirate (EA) culture results were enrolled. Using a threshold of 10(5) cfu/mL, 10 of the 45 (22.2%) quantitative EA cultures were positive, as compared with 7 (15.6%) BAL cultures. When BAL culture findings were used as the reference, the sensitivity and specificity of quantitative EA cultures were 85.7% and 89.5%, respectively, at a threshold of 10(5) cfu/mL, and 85.7% and 94.7%, respectively, at a threshold of 10(6) cfu/mL. Of the 10 EA culture positive patients, 2 patients with a result of -10(5) cfu/mL were BAL culture negative. The quantitative EA culture is a useful non-invasive tool for the diagnosis of pneumonia pathogens. It is suggested that a threshold level of 10(6) cfu/mL is appropriate.

ICU procedures of the critically ill

Intensive Care Unit (ICU) patients often require urgent, high-risk diagnostic and therapeutic procedures. However, they are particularly vulnerable to procedural complications due to the severity and instability of their illnesses. We discuss the complications associated with bronchoscopy, percutaneous dilatational tracheostomy, pleural interventions for example thoracentesis and chest tube placement, central venous catheterization and pulmonary artery catheterization. Invasive procedures are frequently performed in critically ill patients. It is important for the operator to be familiar with the specific complications of each procedure, as well as steps to take in order to enhance safety and reduce adverse events. High standards of training and credentialing are crucial to ensure that the ICU physicians are proficient in performing these procedures.

Comparison of two non-bronchoscopic methods for evaluating inflammation in patients with acute hypoxaemic respiratory failure

Introduction

The simple bedside method for sampling undiluted distal pulmonary edema fluid through a normal suction catheter (s-Cath) has been experimentally and clinically validated. However, there are no data comparing non-bronchoscopic bronchoalveolar lavage (mini-BAL) and s-Cath for assessing lung inflammation in acute hypoxaemic respiratory failure. We designed a prospective study in two groups of patients, those with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and those with acute cardiogenic lung edema (ACLE), designed to investigate the clinical feasibility of these techniques and to evaluate inflammation in both groups using undiluted sampling obtained by s-Cath. To test the interchangeability of the two methods in the same patient for studying the inflammation response, we further compared mini-BAL and s-Cath for agreement of protein concentration and percentage of polymorphonuclear cells (PMNs).

Methods

Mini-BAL and s-Cath sampling was assessed in 30 mechanically ventilated patients, 21 with ALI/ARDS and 9 with ACLE. To analyse agreement between the two sampling techniques, we considered only simultaneously collected mini-BAL and s-Cath paired samples. The protein concentration and polymorphonuclear cell (PMN) count comparisons were performed using undiluted sampling. Bland-Altman plots were used for assessing the mean bias and the limits of agreement between the two sampling techniques; comparison between groups was performed by using the non-parametric Mann-Whitney-U test; continuous variables were compared by using the Student t-test, Wilcoxon signed rank test, analysis of variance or Student-Newman-Keuls test; and categorical variables were compared by using chi-square analysis or Fisher exact test.

Results

Using protein content and PMN percentage as parameters, we identified substantial variations between the two sampling techniques. When the protein concentration in the lung was high, the s-Cath was a more sensitive method; by contrast, as inflammation increased, both methods provided similar estimates of neutrophil percentages in the lung. The patients with ACLE showed an increased PMN count, suggesting that hydrostatic lung edema can be associated with a concomitant inflammatory process.

Conclusions

There are significant differences between the s-Cath and mini-BAL sampling techniques, indicating that these procedures cannot be used interchangeably for studying the lung inflammatory response in patients with acute hypoxaemic lung injury.

The difficult airway in adult critical care

INTRODUCTION

The difficult airway is a common problem in adult critical care patients. However, the challenge is not just the establishment of a safe airway, but also maintaining that safety over days, weeks, or longer.

AIMS

This review considers the management of the difficult airway in the adult critical care environment. Central themes are the recognition of the potentially difficult airway and the necessary preparation for (and management of) difficult intubation and extubation. Problems associated with tracheostomy tubes and tube displacement are also discussed.

RESULTS

All patients in critical care should initially be viewed as having a potentially difficult airway. They also have less physiological reserve than patients undergoing airway interventions in association with elective surgery. Making the critical care environment as conducive to difficult airway management as the operating room requires planning and teamwork. Extubation of the difficult airway should always be viewed as a potentially difficult reintubation. Tube displacement or obstruction should be strongly suspected in situations of new-onset difficult ventilation.

CONCLUSIONS

Critical care physicians are presented with a significant number of difficult airway problems both during the insertion and removal of the airway. Critical care physicians need to be familiar with the difficult airway algorithms and have skill with relevant airway adjuncts.

Multiplanar reconstruction: a new method for the diagnosis of tracheobronchial rupture?

OBJECTIVE

To compare multiplanar reconstruction with operative techniques (bronchoscopy, surgery and/or autopsy) for the diagnosis of tracheobronchial rupture.

DESIGN

Prospective, observational study.

SETTING

Surgical intensive care unit.

PATIENTS AND PARTICIPANTS

Tracheobronchial rupture was suspected on clinical grounds and from radiological findings.

INTERVENTIONS

An initial helical computed tomography scan was performed on all patients meeting the inclusion criteria, and operative techniques were then performed. Multiplanar reconstructions were reformatted and reviewed by two independent radiologists.

MEASUREMENTS AND RESULTS

Twenty-four consecutive patients met the inclusion criteria. Tracheobronchial rupture was diagnosed in 13 patients by at least one operative technique. Multiplanar reconstructions were positive in 15 patients. The diagnostic sensitivity and specificity of multiplanar reconstructions were 100% (95%CI, 85-100) and 82% (95%CI, 64-82), respectively. The positive and negative predictive values were 87% (95%CI, 74-87) and 100% (95%CI, 78-100), respectively. For tracheobronchial rupture, the positive and negative likelihood ratios were 5.5 (95%CI, 2.35-5.5) and 0 (95%CI, 0-0.24), respectively. The Kappa coefficients were 0.83 (95%CI, 0.6-1.06) for agreement between operative techniques and multiplanar reconstruction, and 0.91 (95%CI, 0.59-0.91) for agreement between the two radiologists.

CONCLUSIONS

Multiplanar reconstruction appears to be a sensitive technique for the identification of tracheobronchial rupture because of its excellent negative likelihood ratio. In clinical practice, negative multiplanar reconstruction can exclude a diagnosis of tracheobronchial rupture, making bronchoscopy unnecessary. When multiplanar reconstruction is positive, tracheobronchial rupture should be confirmed by bronchoscopy.

DESCRIPTOR

Trauma.

Functional implications of BAL in the presence of restrictive or obstructive lung disease

Most of the complications associated to bronchoscopy are related to changes of the respiratory function during or after its performance. Prevention of complications should be achieved by understanding the effects of bronchoscopic procedures and their relation to the pulmonary function deterioration. Previous studies regarding the functional impairment caused by bronchoalveolar lavage (BAL) were mostly limited by the presence of interferent factors such as sedative drugs. Furthermore, it is not clear whether or not patients with different ventilatory disturbances present the same functional response to bronchoscopy and BAL. The aim of this study was to determine the additional effects of BAL over the respiratory function deterioration related to bronchoscopy in patients with different respiratory function profiles (normal, restrictive and obstructive). Forty patients submitted to bronchoscopy without premedication were divided into four groups: group I-normal pulmonary function submitted to basic bronchoscopy; group II-bronchoscopy in combination with BAL, subdivided according to pulmonary function: group IIa (normal function), group IIb (restrictive ventilatory disturbances) and group IIc (obstructive ventilatory disturbances). Spirometry was made before and after the bronchoscopic procedure. Baseline hemoglobin saturation was compared to the lowest level during the procedure. Functional worsening caused by the procedure was observed with a decrease in forced vital capacity (FVC), forced expiratory volume in the first second (FEV(1)) and Hemoglobin saturation in all groups. Comparison between groups showed no significant difference regarding the changes in FVC (P=0.8324), FEV(1) (P=0.6952) and hemoglobin saturation (P=0.5044). We conclude that standardized BAL, like the one used in our study, does not result in an increased risk for ventilatory impairment compared to bronchoscopy itself, independently of the presence of previous respiratory disease.

Use of endoscopic fibrinogen-thrombin in the treatment of severe hemoptysis

Bronchial artery embolization (BAE) is the treatment of choice in the majority of patients with severe hemoptysis. However, this procedure may be unavailable and even fail or be counterindicated in 4-13% of cases. In these cases, the efficacy of fibrinogen-thrombin (FT) instilled endoscopically as treatment for massive hemoptysis was assessed. Between August 1993 and February 1996 a prospective clinical study was performed. FT instillation was indicated in all patients with severe hemoptysis (> 150 ml/12 h) in whom BAE had failed, was counterindicated or not available. FT was instilled endoscopically. Patients were followed up until June 2001. Eleven of 101 patients (11%) with hemoptysis > 150 ml/12 h in whom BAE was not possible or proved ineffective were included. The severe hemoptysis was controlled immediately in all cases. During the follow-up period (mean: 39.4 months), early relapse of the severe hemoptysis occurred in two patients (18%) and a long-time relapse in one. Mean procedure duration was 3 min and no attributable complications were observed in any case. In conclusion, these results suggest that topical treatment with FT could be considered in the initial endoscopic evaluation of patients with severe hemoptysis while awaiting BAE or surgery, or as alternative treatment to arterial embolization when the latter is not available, has proved ineffective or is counterindicated.

A randomized clinical trial of intermittent subglottic secretion drainage in patients receiving mechanical ventilation

OBJECTIVE

To study the effect of subglottic secretions drainage on the incidence of ventilator-associated pneumonia (VAP) in patients receiving mechanical ventilation.

DESIGN

A randomized clinical trial.

SETTING

A 12-bed general ICU.

PATIENTS

One hundred fifty patients with an expected duration of mechanical ventilation > 72 h were enrolled in the study.

INTERVENTION

Patients were randomly assigned to receive either an endotracheal tube for intermittent subglottic secretions drainage or a standard endotracheal tube.

OUTCOME MEASUREMENTS

Incidence of VAP, duration of mechanical ventilation, length of ICU stay, length of hospital stay, and mortality.

RESULTS

Seventy-five patients were randomized to subglottic secretion drainage, and 75 patients were randomized to the control group. The two groups were similar at the time of randomization with respect to demographic characteristics and severity of illness. VAP was seen in 3 patients (4%) receiving suction secretion drainage and in 12 patients (16%) in the control group (relative risk, 0.22; 95% confidence interval, 0.06 to 0.81; p = 0.014). The other outcome measures were not significantly different between the two groups.

CONCLUSION

Intermittent subglottic secretion drainage reduces the incidence of VAP in patients receiving mechanical ventilation.

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.

Effects of fiberoptic bronchoscopy during mechanical ventilation in a lung model

STUDY OBJECTIVES

To evaluate the effects of fiberoptic bronchoscopy (FOB) on delivered volumes and pressures during mechanical ventilation, utilizing a lung model.

DESIGN

Bench study.

SETTING

Laboratory.

MATERIALS AND METHODS

Using varying-sized endotracheal tubes (ETTs), we ventilated a lung model at two levels of compliance utilizing different modes and parameters of ventilation. After establishing baseline measurements, the bronchoscope was inserted and measurements repeated.

MEASUREMENTS AND RESULTS

During controlled mechanical ventilation (CMV) with a preset high-pressure limit (HPL), tidal volumes (VTs) were reduced from 700 mL to 0 to 500 mL following insertion of the bronchoscope. Increasing the HPL to 120 cm H(2)O resulted in a VT of 40 to 680 mL. Changing from square to decelerating flow waveform resulted in no consistent difference in VT. Auto-positive end-expiratory pressure (auto-PEEP) of 0 to 41 cm H(2)O was present under most conditions. Higher rates and lower peak inspiratory flows were associated with higher levels of auto-PEEP. In the pressure-control (PC) mode, using a preset inspiratory pressure level (IP), VT was reduced from 700 mL to 40 to 280 mL following insertion of the bronchoscope. Maximum IP (100 cm H(2)O) increased VT to 260 to 700 mL. Auto-PEEP was less in the PC mode.

CONCLUSIONS

Extreme care must be taken when bronchoscopy is performed on a patient receiving mechanical ventilation. Extremely low VT and significant auto-PEEP may develop unless flow, respiratory rate, mode, and ETT size are carefully selected. The PC mode delivered more volume than did the CMV mode. When performing FOB during mechanical ventilation, the inside diameter of the ETT should be > or = 2.0-mm larger than the outside diameter of the bronchoscope to maintain volume delivery and minimize the development of auto-PEEP.

Fiberoptic bronchoscopy for diagnosis and treatment

Bedside fiberoptic bronchoscopy is a valuable tool in the diagnosis and treatment of various respiratory conditions in critically ill patients. The fiberoptic bronchoscope allows direct airway inspection, facilitating the diagnosis of benign and malignant airway lesions. In addition, pulmonary secretions or tissue samples can be collected using the bronchoscope and techniques that allow sampling of the lower airways with minimal or no upper airway contamination. Collection of lower airway samples is important in the diagnosis of pulmonary infiltrates in immunocompromised patients, in many patients with ventilator-associated pneumonia, and in selected patients with CAP. The fiberoptic bronchoscope can be used for therapeutic interventions, such as insertion of an endotracheal tube, removal of an aspirated foreign body, clearance of tenacious secretions, promotion of hemostasis in patients with hemoptysis, instillation of drugs, and assistance in the placement of tracheobronchial prostheses (i.e., airway stents). If proper preprocedural training and planning are done and the patient is monitored carefully during the procedure, fiberoptic bronchoscopy can be performed quickly and safely at the bedside in most critically ill patients.

The clinical utility of invasive diagnostic techniques in the setting of ventilator-associated pneumonia. Canadian Critical Care Trials Group

OBJECTIVE

To evaluate the clinical utility of bronchoscopy with protected brush catheter (PBC) and BAL for patients with ventilator-associated pneumonia (VAP).

DESIGN

Prospective cohort study.

SETTING

Ten tertiary care ICUs in Canada.

PATIENTS

Ninety-two mechanically ventilated patients with a clinical suspicion of VAP who underwent bronchoscopy were compared with 49 patients with a clinical suspicion of pneumonia who did not.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

We compared antibiotic use, duration of mechanical ventilation, ICU stay, and mortality. In addition, for patients who received bronchoscopy, we administered a questionnaire (before and after bronchoscopy) to evaluate the effect of PBC or BAL on (1) physician perception of the probability of VAP, (2) physician confidence in the diagnosis of VAP, and (3) changes to antibiotic management. After bronchoscopy results became available, from the physician's perspective, the diagnosis of VAP was deemed much less likely (p < 0.001), confidence in the diagnosis increased (p = 0.03), and level of comfort with the management plan increased (p = 0.02). Following the results of invasive diagnostic tests, in the group that underwent bronchoscopy, patients were receiving fewer antibiotics (31/92 vs 9/49, p = 0.05) and more patients had treatment with all their antibiotics discontinued (18/92 vs 3/49, p = 0.04) compared with the group that did not undergo bronchoscopy. Duration of mechanical ventilation and ICU stay were similar between the two groups, but mortality was lower in the group that underwent bronchoscopy with PBC or BAL (18.5% vs 34.7%, p = 0.03).

CONCLUSIONS

Invasive diagnostic testing may increase physician confidence in the diagnosis and management of VAP and allows for greater ability to limit or discontinue antibiotic treatment. Whether performing PBC or BAL affects clinically important outcomes requires further study.

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.

Usefulness of airway visualization in the diagnosis of nosocomial pneumonia in ventilated patients

Clinical diagnosis of nosocomial pneumonia in ventilated patients remains a challenge in the ICU as none of the clinical biological and radiologic parameters can predict its diagnosis. To our knowledge, however, the accuracy of direct visualization of the bronchial tree has never been investigated.

PURPOSE

To evaluate the interest of airway visualization and to select independent parameters that predict nosocomial pneumonia in ventilated patients.

SETTING

A ten-bed medical-surgical ICU.

METHODS

All consecutive patients suspected of having nosocomial pneumonia who underwent bronchoscopy with protected specimen brush, culture examination of BAL, and direct examination of BAL were studied. Clinical and biological data and airways findings were recorded prospectively. Patients were classified as having pneumonia or not according to the results of distal bacteriologic samples, follow-up, and histologic study. Respective accuracies of each variable were calculated using univariate analysis and stepwise logistic regression.

RESULTS

Ninety-one patients with suspected nosocomial pneumonia were studied. Patients were randomly assigned to a construction group (n = 46) and a validation group (n = 45). Using multivariate analysis, 3 factors were associated with pneumonia (a decrease in PaO2/fraction of inspired oxygen ratio > or = 50 mm Hg, odds ratio [OR] = 9.97, p = 0.026; the presence of distal purulent secretions, OR = 7.46, p = 0.044; the persistence of distal secretions surging from distal bronchi during exhalation, OR = 12.25, p = 0.013). These three factors remained associated with pneumonia in the validation group. Interobserver repeatability of the bronchoscopic parameters was good. Having 2 or more of these 3 independent factors was able to predict pneumonia with a 94% sensitivity and a 89% specificity in the construction group and with a 78% sensitivity and a 89% specificity in the validation group.

CONCLUSION

We conclude that direct visualization of the bronchial tree can immediately and accurately predict nosocomial pneumonia in ventilated patients before obtaining definite results of protected samples.

The effect of fiberoptic bronchoscopy on cerebral hemodynamics in patients with severe head injury

STUDY OBJECTIVE

Concerns exist about the effect of flexible fiberoptic bronchoscopy (FFB) on intracranial pressure (ICP). We studied the effect of FFB on cerebral hemodynamics in patients with severe head injury.

DESIGN

Prior to FFB, patients were anesthetized and muscle relaxants were given as necessary to eliminate coughing. Comparisons were made of mean arterial pressure (MAP), ICP, and cerebral perfusion pressure (CPP) prior to, during, and after FFB, as well as comparisons of mean cerebral hemodynamic values in an 8-hour period before and after FFB. Observations were made of changes in neurologic status post-FFB.

SETTING

Surgical intensive care unit of Level 1 Trauma Center.

PATIENT POPULATION

Fifteen patients with severe head injury in whom ICP was monitored and who required FFB for diagnosis of nosocomial pneumonia or treatment of lobar collapse.

RESULTS

Pre-FFB ICP averaged 14.3 mm Hg (range, 6 to 26 mm Hg). During FFB, patients experienced a mean increase in ICP of 13.5 mm Hg above basal values (p = 0.0001). At peak ICP, MAP increased from a baseline of 92.3 mm Hg (SD +/- 16.1) to 111.5 mm Hg (+/- 13.9). Mean CPP was 83.7 mm Hg at peak ICP (range, 52 to 121 mm Hg), a 14.0% increase over baseline. The ICP and MAP returned to basal levels following bronchoscopy. No patient had a clinically significant increase in ICP or demonstrated any deterioration in Glasgow Coma Scale score or neurologic examination findings post-FFB.

CONCLUSIONS

Although FFB causes an increase in ICP in patients with severe head injury, MAP also rises, and an adequate CPP is maintained. The ICP returns to basal levels after the procedure. When properly performed, FFB does not adversely affect neurologic status in patients with severe head injury.

Bronchoscopic insufflation of room air for the treatment of lobar atelectasis in mechanically ventilated patients

Segmental and lobar pulmonary atelectasis is a common occurrence in mechanically ventilated patients. Standard therapy for atelectasis relies on positive pressure ventilation, positive and expiratory pressure (PEEP), tracheobronchial toilet and regular chest physiotherapy. Various adjuncts to physiotherapy such as bronchoscopic clearance of secretions have not proved to be of additional benefit. Bronchoscopic clearance of secretions followed by insufflation of room air at 30 cm H2O into the atelectatic segment was employed on ten occasions in mechanically ventilated patients. Rapid re-expansion of the collapsed segment or lobe occurred in seven out of the ten treatments.

Adult and paediatric size bronchoscopes for bronchoalveolar lavage in mechanically ventilated patients: yield and side effects

BACKGROUND

Bronchoalveolar lavage is considered a safe procedure. When performed in the mechanically ventilated patient, however, potentially harmful effects on respiratory and haemodynamic functions have been reported in which the size of the bronchoscope may play a part. Two different size bronchoscopes (adult and paediatric) were therefore investigated with regard to bronchoalveolar lavage yield and side effects.

METHODS

Twenty mechanically ventilated patients underwent bronchoalveolar lavage with both adult and paediatric bronchoscopes in a randomised sequential manner.

RESULTS

In a total of 45 pairs of bronchoalveolar lavage procedures no difference was noted between adult and paediatric bronchoscopes with regard to total cell yield, differential cell count, and microbiological results. Peak intratracheal pressure increased with the adult bronchoscope only. Systemic arterial pressures increased more with the adult than with the paediatric bronchoscope. PaO2 decreased with the adult but not with the paediatric bronchoscope.

CONCLUSIONS

The paediatric bronchoscope offers a comparable bronchoalveolar lavage yield in mechanically ventilated patients to the adult bronchoscope, while the respiratory and haemodynamic side effects are significantly lower than with the adult size instrument.