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378 PART 4: Pulmonary Disorders

Soon after the introduction of endotracheal MV, many complications increased from less than 5% to around 15% of all admitted patients in
of positive pressure ventilation were identified. These complications the ICUs, with a constant success rate and therefore a higher number of
3,4
were found to be common and generated concern about the invasiveness patients avoiding the need for intubation. A greater number of patients
of MV. ETI itself has been implicated in a large number of complications. with chronic obstructive pulmonary disease (COPD) or heart failure
Of these, some are directly related to the procedure, such as cardiac were also successfully treated with NIPPV out of the ICU. A limitation of
arrest following ETI and laryngeal or tracheal injury leading to long- these studies is that only patients who received MV in the ICU for longer
term sequelae. Others are ascribable to the fact that the endotracheal than 12 hours were included. Thus, some patients treated with NIPPV
tube bypasses the barrier of the upper airway: An important example for a shorter period and/or outside the ICU may have been excluded as
is nosocomial pneumonia, which carries its own risk of morbidity and well as patients treated outside the ICU.
mortality. Other complications are indirectly related to ETI, such as Similar observational studies performed in France in 1997, 2002,
the need for sedation, which often prolongs weaning and duration of and 2011, 17-19 respectively, showed a major increase in NIPPV use as
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MV. These major safety considerations prompted efforts to develop a first-line ventilation support for all ICU patients requiring mechani-
noninvasive methods for delivering positive pressure ventilation. Thus, cal ventilatory support (16%, 24%, and 31%; p <0.0001). Importantly,
in patients with ARF, the main goal of NIPPV is to provide ventilatory when comparing the three periods, a significant increase of NIPPV
assistance while lowering the risk of adverse events by reducing the need as first-line therapy (52% vs 35%; p <0.0001) was observed among
for invasive MV. Convincing evidence that NIPPV diminishes the risk of those patients who were not intubated before or at ICU admission. The
infectious complications has been obtained not only from randomized French survey published in 2006 indicated that Pressure Support was
18
controlled trials and meta-analysis, but also from multivariate analyses the most usual ventilatory mode (83%) during NIPPV (CPAP—8% and
of large cohort studies and case-control studies, all of which show sub- assist-control ventilation 7%). The last French observational study still
19
stantial decreases in all categories of nosocomial infection. NIPPV is showed a continuing increase in the overall use of NIPPV but interest-
5-7
indeed associated with a reduction in the overall invasiveness of patient ingly, with a slight but significant decrease of its use in case of hypox-
management: Sedation is not given or at low levels, and the use of central emic respiratory failure.
venous lines, urinary catheters, and other invasive devices is consider- Although these results cannot be extrapolated to all ICUs worldwide,
ably reduced, as compared to patients receiving endotracheal MV. 8 they indicate strong trends toward increasing use of NIPPV in ICU
Another important factor in promoting the use of NIPPV is the patients with a variety of conditions, and they also reflect the current
growing number of patients who are either unwilling to accept ETI or approach trying to reduce the invasiveness of ICU management.
considered poor candidates for endotracheal MV because of their fragile The progressive interest regarding NIPPV use can be evidenced by
underlying health status. In these patients, NIPPV can offer a chance the number of articles concerning NIPPV published in the medical
9,10
of recovery with a low risk of complications. Last, by postponing ETI, literature. Figure 44-1 illustrates the number of references concerning
NIPPV may provide a window of opportunity for the physician, family, NIPPV and acute illness published in PUBMED over the years, using
and patient to make informed decisions about the goals of therapy in the keywords “noninvasive mechanical ventilation” or “noninvasive
patients treated with palliative care. 11 mechanical ventilation” or “NIPPV” and “acute respiratory failure.”
■ EPIDEMIOLOGY tions, great care should be taken to identify patients who will most benefit
Despite the growing interest regarding NIPPV use in acute critical situa-
The use of NIPPV in the acute setting has increased markedly since the from NIPPV, especially those with acute-on-chronic respiratory failure
first small case-series were published in the last decade of the 20th cen- and acute cardiogenic edema. It is also essential to identify the patients
20
tury. 12,13 Three multicenter international observational studies on the use who require immediate or rapid ETI, since delaying this procedure may
of MV applied in the ICU have been performed in 1998, 2004, and 2010 reduce the chances of recovery, especially, in the subgroup with acute
by Esteban and colleagues in which 5.183, 4.968, and 8151 consecutive de novo respiratory failure (free of chronic lung disease, suffering from
patients receiving MV over a 1 or 2 months period were evaluated, community-acquired pneumonia, gastric content aspiration, atelectasis,
respectively. 14-16 The surveys showed that the use of NIPPV progressively and mild acute respiratory distress syndrome [ARDS]). In these patients,

Number 450
(n)
All articles
400
Review articles
350

PUBMED references 300

250
200

150

100
50

0
1988-1997 1998-2002 2003-2007 2008-2012
Period (years)
FIGURE 44-1. Evolution of the number of published references in PUBMED regarding noninvasive mechanical ventilation associated to acute respiratory failure over the time.

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