The pulmonary physician in critical care . 3: critical care management of community acquired pneumonia

Acute respiratory failure on varicella pneumonia in Indonesian adult with chronic hepatitis B: A case report and review article

Background

Varicella pneumonia is a rare clinical manifestations and potentially lethal complications of varicella in a previously healthy adult.

Case presentation

An Indonesian male, 44 years old, Javanese ethnic, complained of progressive dyspnea two days. He had previously been contacting varicella from his daughter 3–4 days before dyspnea onset. He showed typical symptoms of varicella, such as fever and vesicles all over the body. He had been in good health despite having a chronic hepatitis B infection. Chest X-ray on admission revealed bilateral diffuse consolidation with air-bronchogram. Diagnosis of varicella pneumonia was based on typical varicella cutaneous, clinical and chest X-ray findings. We installed mechanical ventilatory support in the isolation ward and he received acyclovir and symptomatic treatment. Ventilatory support was removed on the 3rd day. He successfully recovered on the third day and uninstalled an endotracheal tube.

Discussion

The early and accurate diagnosis of varicella pneumonia was based on disease course and chest X-ray. Managing varicella pneumonia with acute respiratory failure was mechanical ventilator support (when needed), an antiviral, and other symptomatic treatment.

Conclusion

Varicella pneumonia is a rare and severe complication with a good prognosis if diagnosed and treated promptly.

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Chronic hepatitis B increases the risk of varicella developing into acute respiratory failure.

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Early diagnosis and prompt treatment give excellent outcome.

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Ventilation mechanical support is a crucial intervention in acute respiratory failure.

Intensive care and invasive ventilation in the elderly patient, implications of chronic lung disease and comorbidities

Aims: Elderly patients have an increasing prevalence of illness that requires consideration of critical care and invasive ventilatory support. Although critical care of even the very elderly can provide value, with increasing age the potential risks of treatment and diminishing returns with respect to quality and quantity of life result in a need for careful evaluation. Variable combinations of impaired organ function, active disease and residual pathology from past disease and injury all affect critical care, with the consequence that the elderly are a very heterogeneous population. Recognizing that critical care is a limited resource, it is important to identify patients who may be at increased risk or least likely to benefit from treatment. Patients with functional impairments, nutritional deficiencies and multiple comorbidities may be at highest risk of poor outcomes. Those with very severe disease, extreme age and requirements for prolonged ventilatory support have high in-hospital mortality. Functional impairments, comorbidities and severity of illness are usually more important considerations than chronologic age. The objective of this review is to identify how common problems of the elderly affect critical care and decisions concerning use of invasive ventilatory support.

Work of breathing using different interfaces in spontaneous positive pressure ventilation: helmet, face-mask, and endotracheal tube

PURPOSE

Noninvasive positive pressure ventilation (NPPV) using a helmet is expected to cause inspiratory trigger delay due to the large collapsible and compliant chamber. We compared the work of breathing (WOB) of NPPV using a helmet or a full face-mask with that of invasive ventilation by tracheal intubation.

METHODS

We used a lung model capable of simulating spontaneous breathing (LUNGOO; Air Water Inc., Japan). LUNGOO was set at compliance (C) = 50 mL/cmH2O and resistance (R) = 5 cmH2O/L/s for normal lung simulation, C = 20 mL/cmH2O and R = 5 cmH2O/L/s for restrictive lung, and C = 50 mL/cmH2O and R = 20 cmH2O/L/s for obstructive lung. Muscle pressure was fixed at 25 cmH2O and respiratory rate at 20 bpm. Pressure support ventilation and continuous positive airway pressure were performed with each interface placed on a dummy head made of reinforced plastic that was connected to LUNGOO. We tested the inspiratory WOB difference between the interfaces with various combinations of ventilator settings (positive end-expiratory pressure 5 cmH2O; pressure support 0, 5, and 10 cmH2O).

RESULTS

In the normal lung and restrictive lung models, WOB decreased more with the face-mask than the helmet, especially when accompanied by the level of pressure support. In the obstructive lung model, WOB with the helmet decreased compared with the other two interfaces. In the mixed lung model, there were no significant differences in WOB between the three interfaces.

CONCLUSION

NPPV using a helmet is more effective than the other interfaces for WOB in obstructive lung disease.

Care of the Surgical ICU Patient with Chronic Obstructive Pulmonary Disease and Pulmonary Hypertension

Chronic obstructive pulmonary disease (COPD) is a progressive chronic disease characterized by airflow limitation that is frequently progressive and associated with respiratory impairment. As the fourth leading cause of death in the United States and Europe, COPD results in a substantial and ever increasing economic and social burden [1]. Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are frequently encountered in the intensive care unit (ICU). Although there is no standardized definition, AECOPD are characterized by a significant change in patient symptoms from baseline accompanied by overall increased airway resistance [2]. These exacerbations carry a significant risk to patients, with 10 % in-hospital mortality and 1-year and 2-year all-cause mortality rates of 43 % and 49 %, respectively, in patients with hypercapnic exacerbations [3]. Other studies note in-hospital mortality rates as high as 30 % with worse outcomes associated with older age, severity of respiratory and non-respiratory organ dysfunction, and hospital length of stay [4]. Given that patients transferred to the ICU with AECOPD are at high risk for complications and adverse outcomes, early diagnosis and management are critical to improve patient outcomes and survival in this population.

Non-invasive respiratory monitoring using long-period fiber grating sensors

In non-invasive ventilation, continuous monitoring of respiratory volumes is essential. Here, we present a method for the measurement of respiratory volumes by a single fiber-grating sensor of bending and provide the proof-of-principle by applying a calibration-test measurement procedure on a set of 18 healthy volunteers. Results establish a linear correlation between a change in lung volume and the corresponding change in a local thorax curvature. They also show good sensor accuracy in measurements of tidal and minute respiratory volumes for different types of breathing. The proposed technique does not rely on the air flow through an oronasal mask or the observation of chest movement by a clinician, which distinguishes it from the current clinical practice.

[Prehospital non-invasive ventilation in Germany: results of a nationwide survey of ground-based emergency medical services]

BACKGROUND AND OBJECTIVES

Non-invasive ventilation (NIV) is an evidence-based treatment of acute respiratory failure and can be helpful to reduce morbidity and mortality. In Germany national S3 guidelines for inhospital use of NIV based on a large number of clinical trials were published in 2008; however, only limited data for prehospital non-invasive ventilation (pNIV) and hence no recommendations for prehospital use exist so far.

AIM

In order to create a database for pNIV in Germany a nationwide survey was conducted to explore the status quo for the years 2005-2008 and to survey expected future developments including disposability, acceptance and frequency of pNIV.

MATERIAL AND METHODS

A questionnaire on the use of pNIV was developed and distributed to 270 heads of medical emergency services in Germany.

RESULTS

Of the 270 questionnaires distributed 142 could be evaluated (52 %). The pNIV was rated as a reasonable treatment option in 91 % of the respondents but was available in only 54 out of the 142 responding emergency medical services (38 %). Continuous positive airway pressure (98 %) and biphasic positive airway pressure (22 %) were the predominantly used ventilation modes. Indications for pNIV use were acute cardiogenic pulmonary edema (96 %), acute exacerbation of chronic obstructive pulmonary disease (89 %), asthma (32 %) and pneumonia (28 %). Adverse events were reported for panic (20 ±  17%) and non-threatening heart rhythm disorders (8 ± 5%), the rate of secondary intubation was low (reduction from 20 % to 10 %) and comparable to data from inhospital treatment.

CONCLUSION

Prehospital NIV in Germany was used by only one third of all respondents by the end of 2008. Based on the clinical data a growing application for pNIV is expected. Controlled prehospital studies are needed to enunciate evidence-based recommendations for pNIV.

Etiology and Outcomes of ARDS in a Rural-Urban Fringe Hospital of South India

Objectives. Etiology and outcomes of acute lung injury in tropical countries may be different from those of western nations. We describe the etiology and outcomes of illnesses causing acute lung injury in a rural populace. Study Design. A prospective observational study. Setting. Medical ICU of a teaching hospital in a rural-urban fringe location. Patients. Patients ≥13 years, admitted between December 2011 and May 2013, satisfying AECC criteria for ALI/ARDS. Results. Study had 61 patients; 46 had acute lung injury at admission. Scrub typhus was the commonest cause (7/61) and tropical infections contributed to 26% of total cases. Increasing ARDS severity was associated with older age, higher FiO₂ and APACHE/SOFA scores, and longer duration of ventilation. Nonsurvivors were generally older, had shorter duration of illness, a nontropical infection, and higher total WBC counts, required longer duration of ventilation, and had other organ dysfunction and higher mean APACHE scores. The mortality rate of ARDS was 36.6% (22/61) in our study. Conclusion. Tropical infections form a major etiological component of acute lung injury in a developing country like India. Etiology and outcomes of ARDS may vary depending upon the geographic location and seasonal illnesses.

Patient outcomes after noninvasive mechanical ventilation at a high dependency unit of an emergency department

OBJECTIVE

To describe the outcome of patients after noninvasive ventilation in a high dependency unit (HDU) of an emergency department (ED). Secondary aims were to define the role of intensive care consultation and to identify variables associated with mortality.

METHODS

Observational, prospective 6-month study.

RESULTS

Two hundred and nine cases were analysed. Thirty-four patients were initially rejected by the intensive care unit (ICU). Physicians in the ED did not request ICU consultation in the remaining 175 (83%) because of 'belief of improvable medical condition in the ED in patients without therapeutic limits' in 93 (group 1) and to 'preset therapeutic limits' or 'comfort measures only' in 82 (groups 2 and 3). Ten out of these 175 were subsequently admitted to the ICU. The global in-hospital mortality rate was 22% (3.3% in the high dependency unit), but only 10% in group 1. Place of referral for ventilation (P<0.001), absence of subsequent ventilation on the general ward (P<0.001), group of assignation (P=0.004), intensive care initial rejection (P=0.022), no previous home ventilation (P=0.028), older age (P=0.03) and longer duration on ventilation (P=0.047) were significantly associated with mortality. In the multivariate regression model, ventilating patients from general wards (odds ratio=7.1; 2.3-25, 95% confidence interval) and ventilation under preset limits (odds ratio=3.57; 1.42-8.98, 95% confidence interval) remained significantly associated with mortality.

CONCLUSION

Noninvasive ventilation is a relatively safe and effective treatment in the ED when performed in carefully controlled settings. ICU consultation may be securely deferred in this setting.

Usefulness of C-reactive protein in monitoring the severe community-acquired pneumonia clinical course

BACKGROUND

The aim of the present study was to evaluate the C-reactive protein level, the body temperature and the white cell count in patients after prescription of antibiotics in order to describe the clinical resolution of severe community-acquired pneumonia.

METHODS

A cohort of 53 consecutive patients with severe community-acquired pneumonia was studied. The C-reactive protein levels, body temperature and white cell count were monitored daily.

RESULTS

By day 3 a C-reactive protein level 0.5 times the initial level was a marker of poor outcome (sensitivity, 0.91; specificity, 0.59). Patients were divided according to their C-reactive protein patterns of response to antibiotics, into fast response, slow response, nonresponse, and biphasic response. About 96% of patients with a C-reactive protein pattern of fast response and 74% of patients with a slow response pattern survived, whereas those patients with the patterns of nonresponse and of biphasic response had a mortality rate of 100% and 33%, respectively (P < 0.001). On day 3 of antibiotic therapy, a decrease in C-reactive protein levels by 0.31 or more from the previous day's level was a marker of good prognosis (sensitivity, 0.75; specificity, 0.85).

CONCLUSION

Daily C-reactive protein measurement after antibiotic prescription is useful in identification, as early as day 3, of severe community-acquired pneumonia patients with poor outcome. The identification of the C-reactive protein pattern of response to antibiotic therapy was useful in the recognition of the individual clinical course, either improving or worsening, as well as the rate of improvement, in patients with severe community-acquired pneumonia.

Noninvasive versus conventional ventilation to treat hypercapnic encephalopathy in chronic obstructive pulmonary disease

OBJECTIVE

We recently reported a high success rate using noninvasive positive pressure ventilation (NPPV) to treat COPD exacerbations with hypercapnic encephalopathy. This study compared the hospital outcomes of NPPV vs. conventional mechanical ventilation (CMV) in COPD exacerbations with moderate to severe hypercapnic encephalopathy, defined by a Kelly score of 3 or higher.

DESIGN AND SETTING

A 3-year prospective matched case-control study in a respiratory semi-intensive care unit (RSICU) and intensive care unit (ICU).

PATIENTS AND PARTICIPANTS

From 103 consecutive patients the study included 20 undergoing NPPV and 20 CMV, matched for age, simplified acute physiology score II, and baseline arterial blood gases.

MEASUREMENTS AND RESULTS

ABG significantly improved in both groups after 2 h. The rate of complications was lower in the NPPV group than in the CMV group due to fewer cases of nosocomial pneumonia and sepsis. In-hospital mortality, 1-year mortality, and tracheostomy rates were similar in the two groups. Fewer patients remained on ventilation after 30 days in NPPV group. The NPPV group showed a shorter duration of ventilation.

CONCLUSIONS

In COPD exacerbations with moderate to severe hypercapnic encephalopathy, the use of NPPV performed by an experienced team compared to CMV leads to similar short and long-term survivals with a reduced nosocomial infection rate and duration of ventilation.

[Managing lower respiratory tract infections in immunocompetent patients. Definitions, epidemiology, and diagnostic features]

Les infections respiratoires basses sont une des principales cause de mortalité dans le monde et les pneumopathies représentent en France la première cause de décès d'origine infectieuse. Trois entités nosologiques distinctes sont habituellement isolées en fonction de la localisation infectieuse : la bronchite aiguë, la pneumopathie et la bronchopneumopathie (atteignant les bronches et le parenchyme pulmonaire). En cas d'infections de l'arbre bronchique dans le cadre d'une bronchopathie chronique on parle de décompensation infectieuse de la maladie bronchique. Les deux principales difficultés diagnostiques de ces infections sont de déterminer la présence d'une participation alvéolaire au processus infectieux et de définir l'agent (ou les agents) pathogènes. Ces deux éléments vont conditionner la prise en charge thérapeutique. En dehors de l'examen physique, indispensable dans ce contexte, seule la radiographie thoracique pourra, en cas de persistance d'un doute, permettre de confirmer la présence d'une participation alvéolaire. Le diagnostic microbiologique pose la question de sa nécessité systématique et celui de sa valeur. Il n'est pas indispensable de réaliser un diagnostic microbiologique de certitude dans tous les cas. La décision de documentation doit répondre à deux impératifs : faisabilité et valeur diagnostique. La valeur d'un prélèvement dépend de son aptitude à mettre en évidence l'agent pathogène et dans certains cas de la possibilité d'en déterminer le profil de sensibilité (qui reste une indication majeure à la réalisation de ces prélèvements).

Comment évaluer, orienter et suivre un patient ayant une pneumonie aiguë communautaire ? Une exacerbation de bronchopneumopathie chronique obstructive ?

L'objectif de cette revue est de présenter une analyse bibliographique de la littérature de ces cinq dernières années concernant les pneumonies aiguës communautaires (PAC) et les exacerbations aiguës de bronchopneumopathies chroniques obstructives (EABPCO). La PAC et l'EABPCO sont des pathologies fréquentes grevées d'une mortalité et/ou morbidité encore élevée de nos jours. La connaissance des facteurs de risque d'évolution compliquée et l'identification des signes de gravité souvent liés au risque de mortalité permettent d'orienter le patient pour un traitement ambulatoire, en hospitalisation conventionnelle ou en secteur de réanimation ; des règles prédictives ont été établies dans ce sens. La littérature concernant les critères de sortie d'hospitalisation et le suivi des patients est plus pauvre.

The need for chest radiography before initiating non-invasive ventilation: a case report

Severe, acute exacerbations of chronic obstructive pulmonary disease are a common presentation to emergency departments in the UK. In this group of patients, clinical examination can be unreliable in excluding a pneumothorax. With the increasing role of non-invasive positive pressure ventilation in these cases, we present a case report that highlights the need for an urgent chest X-ray prior to commencement of non-invasive positive pressure ventilation.

Community-acquired pneumonia

Community-acquired pneumonia (CAP) remains an important cause of morbidity and mortality. Streptococcus pneumoniae is the most common pathogen and respiratory syncitial virus the most important viral pathogen in children. The role of urinary antigen testing and PCR for the diagnosis forS. pneumoniae infection has been an important adjunct to clinical examination, showing good sensitivity and specificity. Host-related immune responses play an important role in defining the severity of illness. Other than the use of Activated Protein C and immunization, the clinical use of therapies designed to modulate these abnormal responses remains largely experimental. The 7-valent vaccine represents a major advance in the prevention of invasive pneumococcal disease. The importance of effective triage and the deleterious effects of deviation from protocols are underscored. Continuous positive pressure ventilation and noninvasive mechanical ventilation are available as options for respiratory support in cases of severe CAP and require further evaluation.

Severe community-acquired pneumonia: what's in a name?

PURPOSE OF REVIEW

Formerly, patients with community-acquired pneumonia admitted to an intensive care unit were considered as having the severe form of the disease. Recently, guidelines have distinguished severe and non-severe community-acquired pneumonia based on clinical definitions. In this review, we describe the different definitions of severe community-acquired pneumonia, and whether a differentiation based on these definitions reflects variation in etiology, risk factors, diagnostic approaches and treatment.

RECENT FINDINGS

New definitions do not seem to accurately identify patients with high risks of mortality; patients not admitted to an intensive care unit could also be diagnosed as having severe community-acquired pneumonia. Host-factors, such as genetic factors and underlying diseases, can influence severity of presentation of community-acquired pneumonia. Distribution of pathogens in severe and non-severe disease forms is comparable. Initial antibiotic therapy in patients with severe disease should provide coverage of Streptococcus pneumoniae and Legionella pneumophila, as delay is associated with worse outcomes. However, recent studies also suggested an additional benefit of atypical coverage in non-severe disease. As a result, initial therapy with a beta-lactam plus a macrolide or an anti-pneumococcal fluoroquinolone is recommended for all patients with community-acquired pneumonia. Furthermore, the value of vaccination against pneumococci to prevent episodes of severe disease is yet unknown.

SUMMARY

As current guidelines do not adequately identify patients with high risk of mortality and intensive care unit admittance, clinical judgment remains important. Based on distribution of pathogens, investigational procedures and therapy recommended in recent guidelines, differentiation between severe and non-severe community-acquired pneumonia does not seem useful. Whether atypical coverage indeed has additional value in non-severe or pneumococcal CAP, however, remains to be determined. In addition, the preventive benefit of influenza and pneumococcal vaccination for development of SCAP awaits further evidence.