Nicolini Antonello,MD , Piroddi Ines Maria Grazia MD, Barlascini Cornelius MD

Letter

The role of non invasive positive pressure ventilation in community-acquired pneumonia : what we must look for ?

TRY: which criteria predict success or failure?

Respiratory Diseases Unit, ASL 4 Chiavarese

General Hospital

via Terzi 43

16039 Sestri Levante

Italy

phone +390185329145

fax +390185329121

mobile +393495952294

To the Editor :

We read the article published by Murad et al. [1] with great interest. Their study

evaluated the role of non-invasive ventilation (NIV) in critically ill patients with

respiratory failure due to community acquired pneumonia (CAP). The study's purpose

was to assess the usefulness of NIV in patients with severe respiratory failure

requiring ventilation and admitted to an intensive care unit; the outcomes were NIV

failure and high mortality. The authors concluded that mortality was not improved in

the NIV group; although, there were clinical characteristics suggested a more

favorable prognosis. In table 1 the authors reported characteristics of patients

placed on ventilatory support: while the NIV group had a milder severity of

illness(APACHE II) than invasive ventilation group; the former surprisingly had

lower paO2/FiO2 ratio at admission 103 (IQR 63-168) vs. 134 ( IQR 75-218) in the

latter. Moreover, a larger number of patients in the NIV group had greater

radiological pulmonary involvement compared to the intubation group: 20 patients

(3 quadrants ), 24 (4quadrants ) in NIV vs 8 ( 3 quadrants ) and 15 ( 4 quadrants )

in the intubation group.

Previous studies showed that the risk of NIV failure and mortality was linked

to a lower paO2/FiO2 at admission, less pulmonary involvement at admission as well

as with less severe illness [2,3]. NIV success is inversely correlated with worsening

radiological infiltrates at 24 h. In the materials and methods sections the authors did

not specify the criteria used to implement NIV or to exclude NIV treatment nor the

criteria for NIV success or NIV failure. The authors, finally conclude that they

observed a high rate of NIV failure (76%) and the NIV group had a statistically

significant increase in acute hospital mortality compared to NIV success group. There

is no discussion of selection or therapeutic protocols. It is clear that without a

established statement of clinical management: it is impossible evaluate whether

a technique has therapeutic benefit. Several studies suggested criteria to implement

NIV in patients with severe respiratory failure due to CAP [3,4,5,6,7]. In strictly

selected patients with severe respiratory failure due to Influenza H1N1 pneumonia

presenting with Simplified Acute Physiology Score (SAPS) II lower than34, focal

bilateral infiltrates [6], paO2/FiO2 at admission higher than 150 and after 1 h of NIV

higher than 175 [5,7], Santo et al. observed a 87.5% NIV success rate[8].

Moreover, two recent randomized controlled (RCT) studies were published concerning

the use of helmet CPAP versus oxygen therapy in severe hypoxemic respiratory

failure due to pneumonia[9,10]. The latest showed significantly fewer endotracheal

intubations in the helmet CPAP group (63% vs 15% p<0.001)[10]. In conclusion, the

most recent literature suggests that patients with severe respiratory failure are less

likely to be intubated, when NIV support is added to the standard medical

treatment; the key to success is patient selection and early implementation of NIV [11].

REFERENCES

[1] Murad A, Li PZ, Dial S, Shahin J. The role of noninvasive positive pressure ventilation in community-acquired pneumonia. J Crit Care 2015;30:49-54

[2] Carrillo A, Gonzales-Diaz G, Ferrer M,Martinez-Quintana ME, Lopez-Martinez A,Llamas N et al. Non-invasive ventilation in community acquired pneumonia and severe acute respiratory failure. Intensive Care Med 2012;38:458-66

[3] Nicolini A,Ferraioli G,Ferrari-Bravo M,Barlascini C,Santo M,Ferrera L . Early noninvasive ventilation treatment for respiratory failure due to severe community-acquired pneumonia.Clin Resp J 2014 [Epub ahead of print]

[4] De Pascale G,Bello G,Tumbarello M,Antonelli M.Severe pneumonia in intensive care:cause,diagnosis,treatment and management : a review of the literature.Curr Opin Pulm Med 2012;18:213-21

[5]Antonelli M,Conti G,Esquinas A : A multiple-center survey on the use in clinical practice of noninvasive ventilationas a first line intervention for acute respiratory distress syndrome. Crit Care Med 2007;35:18-25

[6] Pelosi P,Rocco PRM,Gama de Abreu M.Use of computed tomography scanning to guide lung recruitment and adjust positive-end expiratory pressure .Curr Opin Crit Care 2011;17: 267-74

[7] Conti G,Costa R.Noninvasive ventilation in patients with hypoxemic,nonhypercapnic acute respiratory failure Clin Pulm Med 2011;18(2):83-7

[8] Santo M., Bonfiglio M,Ferrera L,Nicolini A,Senarega R,Ferraioli G,Barlascini C. High success and low mortality rates with early use of non invasive ventilation in Influenza A H1N1 pneumonia. Infect Dis Clin Pract. 2013;21(4):247-52

[9]Cosentini R, Brambilla AM, Aliberti S,Bignamini A,Nava S,Maffei A et al. Helmet continuous positive airway pressure versus oxygen therapy to improve oxygenation in community acquired pneumonia : a randomized controlled trial. Chest 2010:138:114-20

[10] Brambilla AM,Aliberti S,Prina E,Nicoli F,Del Forno M,Nava S,et al.Helmet CPAP vs oxygen therapy in severe hypoxemic respiratory failure due to pneumonia. Intensive Care 2014;40:942-49

[11]Brochard L, Lefebvre JC,Cordioli RC,Akoumianaki E,Richard JCM.Noninvasive ventilation for patients with hypoxemic acute respiratory failure. Semin Resp Crit Care Med 2014;35:492-500