Non-invasive ventilation in the treatment of severe community acquired-pneumonia : the experience of a single center
Perazzo Alessandro MD, Gatto Piergiorgio MD, Colamartino Simona MD,
Torreggiani Tullio*, ?MD!!!!
Barlascini Cornelius* MD, Nicolini Antonello MD
Respiratory Medicine Unit, Hospital of Sestri Levante, Italy
*Hygiene Unit , ASL4 Chiavarese, Italy
Corresponding author
Perazzo Alessandro
Respiratory Medicine Unit
Via Terzi 43
16049 Sestri Levante – Italy
Phone 00390185329145
Fax 00390185329935
Mobile 00393495952294
e-mail:
The authors have no conflicts of interest to declare
Background:
Treatment of severe community acquired-pneumonia(SCAP) includes
antibiotic therapy as well as hemodynamic and ventilatory support. The use of invasive
ventilation maybe associated with greater acute morbidity. For this reason non-invasive
ventilation (NIV) has been used for acute respiratory failure to avoid endotracheal
intubation. However, few studies have assessed the efficacy of NIV in patients with pneumonia. NIV is controversial in SCAP . There is greater variability in NIV failure in SCAP than in other pulmonary diagnoses
Methods:
We prospectively assessed 65 patients with CAP and severe acute respiratory
failure (ARF) (paO2/FiO2 ≤250); 28 had “de novo” ARF and 37 previous cardiac
or respiratory disease. We assessed predictors of NIV failure and hospital
mortality in univariate and multivariate analyses.
Results:
NIV failed in 13 patients (20.0%) in
patients with “de novo”ARF and previous cardiac or respiratory disease (
17.8% versus 21.6% ). Higher chest X-ray score at
admission, higher heart rate after 1h of NIV and a higher alveolar-arteriolar
gradient (A-aDO2) after 24 h of NIV independently predicted NIV failure.
Conclusions:
NIV success is related to a strict selection and monitoring of the patient. Similar NIV
failure rates were observed in patients with "de novo" and previous cardiac or respiratory
disease. There are clinical parameters that predict NIV
failure and mortality
Key words : severe community acquired pneumonia (SCAP), severe respiratory failure, non-invasive ventilation (NIV), NIV failure, hospital mortality
BACKGROUND
Severe community-acquired pneumonia (SCAP) have been defined pneumonia
requiring admission to the intensive care unit (ICU) or carrying a high risk of
death [1]. Treatment of SCAP consists in antibiotic therapy and
ventilatory and hemodynamic support [1,2,]. Invasive ventilation causes
BE specific; also the admission to ICU itself can be cause of complications
because of invasive monitoring EXPLAIN[3] : For these reasons non-invasive
ventilation (NIV) outside ICU has been used for acute respiratory failure to avoid
endotracheal intubation and/or ICU admission. Few studies have assessed
the utility of NIV in patients with pneumonia. NIV is
considered controversial because of a greater variability in failure rates in SCAP than
those observed in chronic obstructive pulmonary disease (COPD) or
cardiogenic pulmonary edema [2].
PART2 START HERE
From studies done in the recent past, it may that there is less “controversy” and more clarity. Factors predicting where NIV is not indicated [3,4,5] have emerged. In a recent study Carrillo et al. demonstrated the value of the following parameters as predictors of NIV failure: worsening radiological infiltrates 24 h after admission, high sepsis-related organ failure assessment (SOFA) score at admission and SOFA after 1 h of NIV, higher heart
rate,lower PaO2/FIO2 and bicarbonate [2]. The use of NIV in SCAP
increased during H1N1 pandemic; over time the number of NIV successes progressively
increased [6]. More recently Brambilla et al. in two randomized studies
demonstrated that helmet CPAP reduced intubation rate in patients with severe
respiratory failure due to pneumonia [7,8]. Since the available evidence on the
Appropriate patient selection is the most important in NIV success [2,9]. In our
institution we have used NIV for the management of patients with severe
respiratory failure ( including pneumonia ) for more than ten years; we have
developed a specific protocol for the Emergency Department to promote a strict
selection criteria for NIV use in SCAP[9]. The aim of this study was
to evaluate the clinical results in SCAP patients with acute respiratory failure (ARF). We asked which characteristics were associated with resolution of the pathological process using NIV. We asked which factors predicted NIV failure and which characteristics were associated with mortality
Evolution? NO, RESOLUTION- YES
METHODS
This study was approved by the Ethics Committee of the
ASL Chiavarese, Chiavari, Italy AND CONFORMED TO THE HELSINKI DECLARATION.
STUDY NUMBER?????. Patient identification remained anonymous and the requirement for informed consent was waived because of the observational nature of the study.
We prospectively followed 65 consecutive patients with severe ARF due to SCAP defined
as PaO2/FIO2 ratio ≤250 receiving NIV treatment in a respiratory monitoring
unit (RMU) of the Hospital of Sestri Levante , ASL4 Chiavarese, Italy from June
2009 to December 2012.
START HERE with definitions
Pneumonia was defined as a pulmonary infiltrate on the admission chest
radiograph with symptoms and signs of lower respiratory tract infection
following American Thoracic Society and Infectious Disease Society of America
(IDSA/ATS) guidelines [2,11].
Patients’ degree of severity and organ failure were estimated with Simplified
Acute Physiology Score (SAPS)-II and Confusion, blood urea
nitrogen, (respiratory rate and arterial blood pressure plus age ≥65 years (CURB65) score [2].
, (emo con formula, Creatinine, sodium would be important to me as a reviewer. I was one years ago)
ARF whether hypoxic or hypoxic with hypercapnia was
considered “ de novo “ in patients without previous cardiac or respiratory disease [2].
Institutional inclusion and exclusion criteria were applied .
Exclusion criteria were any degree of immunosuppression, lack of spontaneous
breathing(the choice is dead or already intubated / ventilate), gasping for air, anatomical evidence of functional airway obstruction and gastrointestinal bleeding or
ileus, massive agitation, severe hypoxemia or acidosis (pH<7.10) [ 2,10,11].
We prospectively followed 65 consecutive patients (who met inclusion criteria, i.e., those who had no criteria for exclusion) with severe ARF due to SCAP defining
as PaO2/FIO2 ratio ≤250 receiving NIV treatment in a respiratory monitoring
unit (RMU) of the Hospital of Sestri Levante , ASL4 Chiavarese, Italy from June
2009 to December 2012. (many hospitals do not permit CAP admission in absence of other life threatening pathology= pneumonia? GO HOME: no beds, no money. DKA without coma and/or pH < 7,20 and no Mi, stroke, obvious sepsis – GO HOME. True in all fields)
START
All patients
received at admission empiric antimicrobial therapy (according to the BTS guidelines) at admissio
[12].Patients with hypotension received initially intravenous fluid therapy with crystalloids
and if necessary vaso-active drugs [2,10]. Patients who responded within one hour to vaso-active drugs
were continued on NIV; patients who did not were admitted to ICU[10]. In all patients specific urinary
tests for Streptococcus pneumoniae and Legionella pneumophila were done; blood culture samples and
trachea-bronchoaspirate cultures were taken from every patients. Only in selected cases
(suspected resistant-bacteria) flexible bronchoscopy with broncho-alveolar lavage( BAL). was performed
STOP
DELETE OR REDUCE To ten words redundant
The indication for NIV was decided by the attending physician following the
internal protocol ( patients in need for emergency intubation because of
respiratory or cardiac arrest, gasping, major agitation not controlled by
sedation, massive aspiration, inability to manage respiratory secretion
appropriately, haemodynamic instability not responder to fluids and vasoactive
drugs,PaO2/FIO2 ratio <100 or < 175 after 1 hour of NIV were admitted to ICU
and intubated) [2,9,10].Also the inability of the patient to adapt himself/herself to
the device or unwillingness to undergo NIV was considered a contraindication
for NIV.
The criteria used for implementing NIV were: moderate to severe
dyspnea accompanied by respiratory rate ≥30 breaths/min or signs of
respiratory distress [2,10] and arterial oxygen tension to inspired
oxygen fraction (PaO2/FIO2) ratio < 250. NIV was applied with NIV
specific platform ventilators (Philips Respironics V60 or Philips
Respironics Vision or Philips Respironics Esprit).Patients were ventilated using
bi-level positive airway pressure ventilation (BIPAP) or continuous positive
airway pressure ventilation (CPAP). Oro-nasal masks were used as first
choice, but total face masks were optionally used if patients did not tolerate
oro-nasal mask. Patients were continuously monitored with
electrocardiogram, pulse oximetry, non-invasive blood pressure and respiratory
rate. Worsening pulmonary infiltrate was defined an increase in pulmonary involvement for at least one lobe compared with a previous X-ray: the comparison was made within the first 24-96 h of ventilation therapy [2].
òòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòòThe following parameters were recorded on admission: age, sex, comorbidities, number of lobes involved on chest x-ray or on chest computed tomography and Opravil radiological score [13]; PaO2 on air room,PaCO2, pH,PaO2/FIO2 ratio, and alveolar-arterial gradient (A-aDO2); Simplified Acute Physiology Score (SAPS) II, and Kelly-Matthay scale; ventilation mode, setting of mechanical ventilator and PaO2/FIO2 after 1 hour of NIV. Moreover, all patients were assessed at admission and daily during follow-up for the presence of hypotension (systolic blood pressure ≤ 90 mmHg), confusion, renal failure, and/or septic shock as well as need for ICU admission, intubation and/or invasive ventilation (IMV).
THESE SENTENCES ARE LONG BUT essential
If a patient on NIV had an improvement of PaO2/FIO2 ratio more than 175 after 1 hour, NIV was continued.
If or one or more complications happened New neurological impairment, persistence of dyspnea, tachypnea, hemodynamic instability, intolerance of the interface, worsening of PaO2/FiO2 ratio) was considered an NIV failure.
(The necessary ventilator setting and FIO2 levels were determined and recorded in accordance with the needs of the patient by the attending physician.)YOU DO NOT NEED THIS SENTENCE
CPAP or EPAP ( expiratory positive airway pressure) was set initially at 5 cm H2O and the level was raised by 1-2 cm H2O if needed to achieve PaO2 ≥ 60 mmHg or SpO2 of ≥ 90%. Inspiratory positive airway pressure (IPAP) was increased, starting to 10 cmH2O, in increments of 2-3 cmH2O to obtain a tidal volume (VT) of 6-8 ml/Kg and a respiratory rate ≤ 30 breaths/m’. CUT SOME OF THIS STUFF; IT DRAGS
NIV was deemed successful when respiratory failure improved and the patient did not feel the need for more than 48 hours of ventilator treatment having a PaO2/FiO2 ratio > 250 with spontaneous breathing.
Statistical analysisdone
Continuous variables expressed as median ( 25-75 IQR ) were compared with the regression analysis corrected for age. Categorical variables (expressed as number and percentages) were compared using X-square test . A p-value ≤0.05 was considered significant. The predictors identified as predictors of NIV failure and hospital mortality were analyzed initially on univariate regression analysis. Then multivariate analysis logistic regression with a conditional stepwise model was employed to correct for co-linearity. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were computed for variables independently associated with NIV failure or hospital mortality. The area under the curve (AUC), optimal cut-off values, sensitivity, specificity, as well as positive and negative likelihood ratio were calculated . Data analysis was done using statistical software R-Project version 2.13.2 done
RESULTS
Patients
65 patients with CAP admitted received NIV ( 38 males and 19 females aged
59.74±16.17 years ) for 90±96 hours (mean ±SD) along 3.7±3.3 days. During
NIV treatment the maximal inspiratory positive pressure (IPAP) was 20±4 cm
H2O and maximal expiratory pressure (EPAP) 8±4 cmH2O respectively. NIV
was successfully used in 52 patients (80.0 %). Among the thirteen patients
with NIV failure, nine were intubated and admitted to ICU. The main reasons for intubation was worsening of respiratory insufficiency in five patients,
cardio-respiratory arrest in two patients, and multi-organ failure in two
patients. The OTHER FOUR
patients died without intubation because THEY had declared before entering the study that they did not want to be intubated. THIS HAS TO BE WHAT YOU MEAN
The four patients who chose not to intubated died because of multiorgan
failure (one ) or worsening of respiratory failure ( three).These four
patients belonged to the cardiac and respiratory disease group. Among the nine
patients admitted to ICU six died (66.6%) (two from the “de novo”
group and the remaining four from the pre-existing the cardiac and/or respiratory disease
group). VERYSMALL N, n=6
Among the two patients belonging to “de novo” group One patient in the “de novo” group died after
cardio-respiratory arrest; the other from multiorgan failure.
Microbiological findings
Causative agents was found in 20 of 65 cases (30.76%):the main pathogens
isolated were Streptococcus pneumoniae, Legionella pneumophila, and
Staphylococcus aureus among bacteria and Influenza A among viruses.
You need more stuff here hiv, hcv, hepb, fungals, more on the virus. I know about it's hard to culture and inf A is usually worse than B. BUTyou did bronchs and aspirations. Less ventilator, more infectious agents
Patients with “de novo” ARF compared with patients with previous cardiac and respiratory disease ARF ( table 1)
We considered, as indicated previously (2),acute respiratory failure “de novo”
when CAP happened in patients without previous cardio-respiratory
comorbidities. Patients with previous cardiac or respiratory disease were older
and more frequently at admission had higher paCO2 and bicarbonate,lower
arterial pH and decreased consciousness.
THESE TWO SENTENCES DO NOT FIT
In the both groups patients had
similar characteristics at admission with except of the age 39.5 (IQR 34-3-55.3) in the
“de novo respiratory failure” group and 80.0 (IQR 63.0-83.0) in previous cardiac or respiratory disease ARF group .
THESE TWO SENTENCES DO NOT FIT. Clarify and I will fix the grammar
Complications of NIV
Twenty-one patients (32,2%) patients had at least one complication related to
NIV. The most common complications were skin lesions ( from erythema to skin
ulceration ) (61.4%), eye irritation (23.8%), claustrophobia (14.2% ) and gastric
distension (14.2% ). Serious complications were not observed because of
an internal protocol for skin lesions and NIV complication prevention. The NIV
duration was similar both in the NIV success group and NIV failure group. Moreover,we
did not observe serious complications due to mask intolerance. Any intolerance of mask type during NIV been prompted a quick switch (e. g., total face mask inside of oro-nasal mask ).
Factors related to NIV failure
Patients in the “de novo”group with NIV failure treatment were more
severe,had more severe scores at admission (CURB 65 and SAPS II),a more
extensive radiologic findings (Opravil score),and a more respiratory
impairment at admission (lower PaO2/FIO2 ratio and higher A-aDO2),a worse