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520 PART 4: Pulmonary Disorders

physiologic TLC and hyperinflation-induced lung injury. A conse- • McMaster MJ, Glasby MA, Singh H, Cunningham S. Lung func-
60
quence of small tidal volume ventilation is reduced alveolar ventilation tion in congenital kyphosis and kyphoscoliosis. J Spinal Disord
and hypercapnia. Hypercapnia can be mitigated by decreasing CO pro- Tech 2007;20:203.
2
duction through the use of sedatives and analgesics (and possibly para-
lytics), treating fever, and avoiding excessive caloric intake. Repleting • Mollica C, Paone G, Conti V, et al. Mechanical ventilation in
intravascular volume and avoiding excessive PEEP may also decrease patients with end-stage idiopathic pulmonary fibrosis. Respiration.
V /V and improve hypercapnia. In patients with chronic ventilatory 2010;79:209.
ds t
failure, we target a minute ventilation that maintains Pa CO 2 greater than • Park IN, Kim DS, Shim TS, et al. Acute exacerbation of intersti-
or equal to baseline to avoid alkalemia and bicarbonate wasting. tial pneumonia other than idiopathic pulmonary fibrosis. Chest.
The use of PEEP avoids tidal collapse of alveoli at low lung volumes 2007;132:214.
and may help recruit fluid-filled and atelectatic lung units. We gener- • Rangappa P, Moran JL. Outcomes of patients admitted to the
ally start with 5 cm H O PEEP and increase in an attempt to achieve
2 intensive care unit with idiopathic pulmonary fibrosis. Crit Care
90% arterial saturation with an Fi O 2 of 0.6 or less. Requirement for high Resusc. 2009;11:102.
PEEP (>10 cm H O) is a bad prognostic sign in ILD that has been inde-
2
pendently associated with decreased survival in mechanically ventilated • Saydain G, Islam A, Afessa B, et al. Outcome of patients with idio-
105 of 1.0 is desirable in the peri-intubation period, pathic fibrosis admitted to the intensive care unit. Am J Respir Crit
patients. Though Fi O 2 Care Med. 2002;166:839.
it should be decreased as quickly as possible to avoid oxygen toxicity.
The use of sedatives, analgesics and muscle relaxants to decrease oxygen
–
consumption and optimal PEEP and increasing Pv allows for nontoxic
in many cases. O 2 REFERENCES
Fi O 2
High alveolar pressures compress alveolar vessels, diverting blood
flow from ventilated units and increasing dead space. Increasing V /V Complete references available online at www.mhprofessional.com/hall
t
ds
from 0.4 to 0.6 requires an increase in minute ventilation of 50% to
. However, during positive pressure ventila-
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maintain a constant Pa CO 2
tion, increasing minute ventilation may increase alveolar pressure and
V /V further, creating a potentially vicious cycle if minute ventilation CHAPTER Ventilator-Associated
ds t
is continually increased in a misguided attempt to lower Pa CO 2 . High Pneumonia
thereby decrease venous return to the right atrium, cardiac output, Pv , 59
alveolar and pleural pressures also increase right atrial pressure and
–
O 2
and systemic blood pressure. Additionally, high alveolar pressures may Jean Chastre
divert blood flow to nonventilated units, as in pneumonic consolidation, Jean-Yves Fagon
and worsen hypoxemia.
■ LONG-TERM MANAGEMENT OF IDIOPATHIC PULMONARY FIBROSIS KEY POINTS
Because no drug therapy has clearly been demonstrated to benefit patients • The risk of nosocomial pneumonia is considerably higher in the
with IPF, long-term management is largely supportive. We suggest refer- subset of ICU patients treated with mechanical ventilation, with an
69
ral to a regional center of expertise for consideration of enrollment in a incremental risk of about 1% per day of ventilation.
clinical trial or evaluation for lung transplantation, particularly for patients • Ventilator-associated pneumonia (VAP) is associated with mor-
who have required hospitalization for an episode of acute clinical decom- tality in excess of that caused by the underlying disease alone,
pensation. Further study is needed to determine predictors of disease particularly in case of infection due to high-risk pathogens, such
86
progression in IPF. The poor outcomes in patients with IPF admitted to as Pseudomonas aeruginosa and Acinetobacter spp and when initial
72
the ICU underscores the importance of advance directives. antibiotic therapy is inappropriate.
• The predominant organisms responsible for infection are
Staphylococcus aureus, P. aeruginosa, and Enterobacteriaceae, but
KEY REFERENCES
etiologic agents differ widely according to the population of hospital
• Conti G, Rocco M, Antonelli M, et al. Respiratory system mechan- patients, duration of hospital stay, and prior antimicrobial therapy.
ics in the early phase of acute respiratory failure due to severe • Although appropriate antibiotics may improve survival in patients
kyphoscoliosis. Intensive Care Med. 1997;23:539. with VAP, use of empirical broad-spectrum antibiotics in patients
• Gaudry S, Vincent F, Rabbat A, et al. Invasive mechanical ventila- without infection is potentially harmful, facilitating colonization
tion in patients with fibrosing interstitial pneumonia. J Thorac and superinfection with multiresistant microorganisms. Any
Cardiovasc Surg. 2014;147(1):47-53. strategy designed to evaluate patients suspected of having devel-
• Gonzalez C, Ferris G, Diaz J, et al. Kyphoscoliosis ventilatory- oped VAP therefore should be able to withhold antimicrobial
insufficiency: effects of long-term intermittent positive-pressure treatment in patients without pneumonia.
ventilation. Chest. 2003;124:857. • Because even a few doses of a new antimicrobial agent can negate
• Hart N, Hunt A, Polkey MI, Fauroux B, Lofaso F, Simonds AK. results of microbiologic cultures, pulmonary secretions in patients
Comparison of proportional assist ventilation and pressure support suspected of having developed VAP always should be obtained
ventilation in chronic respiratory failure due to neuromuscular before new antibiotics are administered.
and chest wall deformity. Thorax. 2002;57:979. • Quantitative techniques, when performed before introduction of
• Lancaster LH, Mason WR, Parnell JA, et al. Obstructive sleep apnea new antibiotics, enable physicians to identify most patients who
is common in idiopathic pulmonary fibrosis. Chest. 2009;136:772. need immediate treatment and help to select optimal therapy in a
• Ley B, Collard HR, King TE Jr. Clinical course and prediction of manner that is safe and well tolerated.
survival in idiopathic pulmonary fibrosis. Am J Respir Crit Care • Empirical treatment of patients with VAP should be selected based on
Med. 2011;183:431. available epidemiologic characteristics, information provided by direct

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