Crit Care Nurs QVol. 27, No. 4, pp. 325–335
c 2004 Lippincott Williams & Wilkins, Inc. Cynthia Kane, MS, RN, APRN; Susan Galanes, MS, RN, APRN
ARDS or acute respiratory distress syndrome continues to be a considerable critical care challenge. Mortality has not decreased significantly over the last more than 30 years. This article presents an overview of origin, evaluation, and treatment of ARDS. Recent findings relative to onset and pre- cipitators of ARDS have led to changes in evaluation and treatment plans. Clinical and radiologic descriptors in assessment of the patient with ARDS are discussed. Ventilatory modes and nurs- ing interventions to optimize patient outcomes are identified. The challenges of outcomes issues presented offer opportunities for further study. Key words: adult respiratory distress syndrome, ARDS, high-frequency ventilation, nitric oxide, outcomes EPIDEMIOLOGY/INCIDENCE
tory distress syndrome, to distinguish it fromthe infant respiratory distress syndrome. The
Acute respiratory distress syndrome (ARDS)
was introduced into the medical literature by
ence on ARDS decided that there should be a
Ashbaugh and colleagues in 1967, when they
return to the original term acute rather than
described 12 patients who developed a res-
adult, since the syndrome is not limited to
piratory distress syndrome which was mani-
fested by acute onset of hypoxemia, tachyp-
diffuse alveolar infiltrates on chest x-ray.1 Of
lung injury (ALI) and ARDS.2,3 Both are acute
these 12 patients, 7 had severe trauma, 4 had
in onset, last for days to weeks, are char-
viral infections, and 1 had acute pancreatitis.
acterized by arterial hypoxemia resistant to
The mortality rate was 58% (7 of 12 patients).
oxygen therapy alone, and display diffuse ra-
Case reports dating back to World War I and
diologic infiltrates. Both definitions include a
World War II revealed that trauma and sepsis
pulmonary artery wedge pressure (PAWP) of
may affect pulmonary function. However, it
became more evident during the Vietnam era,
sured, or no clinical evidence of left atrial hy-
as patients who previously would have died
pertension. The difference in definition be-
were resuscitated with advanced medical care
tween ALI and ARDS is related to oxygenation,
and went on to develop the above pulmonary
defined as PaO2/FiO2 ≤ 300 mm Hg for ALI cri-
manifestations. Their 1967 paper was the first
teria, and PaO2/FiO2 ≤ 200 mm Hg for ARDS
to define the ARDS. In the following years, this
syndrome was referred to as the adult respira-
tory distress syndrome was introduced intothe literature, there have been thousandsof publications addressing all aspects of
From the Suburban Lung Associates, Elk Grove
ARDS. It is estimated that there are 150,000
Village, Ill (Ms Kane); and the Suburban Lung
cases of ARDS in the United States annually.4
Associates, Winfield, Ill (Ms Galanes).
Incidence of ARDS throughout the world has
Corresponding author: Cynthia Kane, MS, RN, APRN,
been variable, ranging from 1.5 to 13.4 cases/
Suburban Lung Associates, 801 Biesterfield Rd, Elk
100,000/year.5–8 Only one of these studies
Grove Village, IL 60007 (e-mail: cindy.kane@sublung. com).
addresses incidence using the ALI and ARDS
CRITICAL CARE NURSING QUARTERLY/OCTOBER–DECEMBER 2004
PATHOPHYSIOLOGY
European Consensus Conference. Furtherstudies defining incidence using the new
fined by physiologic and radiologic criteria
Mortality rate for ARDS is between 40% and
60% and has remained in this range with lit-
alveolar-capillary membrane composite oc-
tle change over the last 30 years despite ex-
curs within hours to days of a predispos-
tensive research and literature devoted to it.9
ing insult.17 The National Heart, Lung, and
In 1995, Krafft reported that the standard
for outcome in ARDS should be a mortality
group consensus is that ARDS is a systemic
syndrome.17,18 Systemic responses to stress
promise with a decline in mortality,10,11 and
involve neural, endocrine, pro and antiin-
flammatory mechanisms that are adaptive or
use of permissive hypercapnea and low tidal
Specifically, cells of the alveolar-capillary
membrane as well as those of the immune andhemostatic systems are targets of damage, and
ETIOLOGY/PRECIPITATORS
The alveolar-capillary barrier comprises the
There are a number of clinical conditions
that result in systemic inflammation leading
lar endothelium. As endothelial permeabil-
to the lung injury process with ARDS. The
ity increases, protein-rich edema fills the
air spaces.17 Resultant damage to epithelial
on ARDS recommended categorizing the risk
type 2 cells causes surfactant production to
factors into direct and indirect categories.2,3
decrease.19 Further disruption of alveolar/
The direct-injury risk factors include aspira-
epithelial integrity leads to increased perme-
tion, diffuse pulmonary infection (eg, bac-
ability and alveolar flooding of edema. In addi-
terial, viral, or pneumocystis infection etc),
tion, neutrophils adhere to the damaged cap-
near-drowning, toxic fume inhalation, and
illary membrane and transfer into alveolar air
lung contusion. The indirect injury risk fac-
tors include sepsis syndrome with or without
Alveolar macrophages secrete cytokines; in-
hypotension or evidence of infection outside
terleukins 1, 6, 8, and 10; and tumor necro-
the lung; severe nonthoracic trauma; hyper-
sis factor alpha (TNF-α).18 These act locally to
transfusion for emergency resuscitation; and
advance chemotaxis and activate neutrophils,
ARDS increases when sustained hypotension
creasing contractility. Alveolar epithelial cells
occurs.2,3 In 1995, Hudson et al found that
produce cytokines in response to stimuli such
the highest incidence of ARDS occurred in pa-
as lung stretch, which is exacerbated by me-
tients with sepsis syndrome (43%) and those
chanical ventilation forces. The degree of alve-
olar epithelial injury is an important predictor
(40%).14 Garber et al showed a strong cause-
of outcomes.17 Lung stretch induces local and
effect relationship for increased incidence of
systemic cytokine release. These mechanical-
ARDS with sepsis, aspiration, trauma, and mul-
ventilation–based mediators, endotoxins, and
tiple transfusions.15 Other inciting factors in-
bacteria, may also translocate into systemic
clude cardiopulmonary bypass, fat embolism,
circulation.17,18 Genetic factors may be re-
pancreatitis, and drug overdose.2,3,14 Inciden-
sponsible for its onset, as significantly smaller
tally, it is also noted that the incidence of
subsets of patients in any ARDS trigger group
ARDS in severe acute respiratory syndrome
go on to develop this severe inflammatory
Adult Respiratory Distress Syndrome
The first phase is the acute or exudative
silhouette. Infiltrates are generally focal, and
phase, with rapid onset of respiratory fail-
may be very similar to those of severe car-
ure, bilateral infiltrates, and refractory hy-
poxemia. Diffuse alveolar damage occurs and
serial chest radiographs often show rapid
progresses rapidly. This occurs in context of
progression of dependent bilateral infiltrates
capillary injury and disruption of the alveo-
progressing to diffuse interstitial infiltrates
lar capillary membrane. Other complications
include mechanical-ventilation–induced baro-
demonstrated that alveolar consolidation and
Later phase changes include a subgroup of
atelectasis occur most often in dependent
patients who progress to fibrosing alveolitis
lung zones; other areas may be relatively
complicated by alveolar tissue necrosis.17 Pul-
spared.24 However, even areas that appear rel-
monary hypertension may be severe17,18,20;
atively radiologically spared may have substan-
however, in many patients radiographic and
tial inflammation present.23 Bugedo found
pulmonary function tests return to normal.
improved aeration of poorly aerated and non-aerated tissue by 16% and 33%, respectively,
EVALUATION OF ARDS
per CT during recruitment measures.25 Radio-logic follow-up should be closely monitored,
Clinical examination
as some patients show progression to fibros-
ing alveolitis with linear opacities consistent
supporting data, but little definitive diagnos-
tic clarity. ARDS usually develops within 24
to 48 hours of initial injury or insult,18,20
plicating factor, which has been reported to
and clarification of clinical examination find-
occur in 10% to 13% of ARDS cases, and is
ings over a short duration may be difficult.
not clearly related to levels of positive end-
Dyspnea with tachypnea generally presents
expiratory pressure or airway pressure.17,18,23
first, and patients may be in considerable
respiratory distress.20 This often is accompa-
with higher level plateau pressures.17,18
nied by shallow inspiratory effort, as compli-
ance decreases. Tissue perfusion alterations
ment has been evaluated by use of positron
emission tomography (PET) scans. Although
mottled, or cyanotic. Auscultation will reveal
initial data has been promising, barriers exist
characteristic findings associated with the
related to availability and some difficulty clar-
predisposing cause, and may include crack-
ifying pulmonary edema due to left heart fail-
les, decreased sounds, or wheeze. As ARDS
progresses and both compliance and pro-inflammatory changes worsen, lung sounds
Blood gas analysis
may become significantly decreased, with ar-eas of consolidation and pneumonia.17,20 Ap-
Arterial blood gas (ABG) analysis is key to
plication of end-expiratory pressure compli-
evaluation of patients with suspected ARDS.
cates assessment. In addition, if the patient
is being managed on oscillating ventilation or
of proportion to chest x-ray. Pulmonary right
high-frequency ventilation, accuracy of aus-
to left shunting because of infiltrates and at-
electatic areas contribute to worsening hy-poxemia, which is resistant to increasing FiO2. Initial presentation of respiratory alkalosis
Radiologic evaluation
Chest radiographs usually show diffuse bi-
PaCO2 and elevated pH is an early indication of
lateral infiltrates, but with a normal cardiac
progression of diffuse alveolar compromise.27
CRITICAL CARE NURSING QUARTERLY/OCTOBER–DECEMBER 2004
in tissue perfusion. Generally, patients with
ence defines ARDS as PaO2/FiO2 < 200, bilat-
ARDS do better when kept on the dry side.20
eral infiltrates, and PAWP ≤ 18 mm Hg, or no
Complications such as acute cor pulmonale
clinical evidence of left atrial hypertension.18
may be minimized by protective ventilation.30
This may be preceded by acute lung injury
In addition, recruitment maneuvers may be
with a PaO2/FiO2 ratio of less than 300. After
associated with hypotension, but this is not
treatment is initiated, the goal FiO2 is less than
60%, as hyperoxia can lead to excessive oxi-dant production, protein oxidant damage, and
Late-phase clinical evaluation
Clinical manifestations of the fibroprolifer-
ative phase include fever, leukocytosis, dif-
treatment ensues, current recommendations
fuse alveolar infiltrates on chest radiograph,
include low tidal volumes. Significant airway
and persistent inflammatory mediators in the
trauma decreases when there is no recurrent
serum.17,18 Associated physiologic manifesta-
opening and closing of alveoli, which tradi-
tions include worsening of pulmonary com-
tionally occurs with higher tidal volumes.12
pliance, abnormal gas exchange, increased
A consequence of this volume-related avoid-
dead space ventilation, pulmonary hyperten-
tilation. This in turn increases the PCO2,which then lowers the pH. Although aci-
TREATMENT AND COURSE
dosis increases the significant inflammatoryprocess, the negative effects of barotraumas/
Identification and treatment
volutrauma are lessened because of this lower
of precipitator
tidal volume. The net result has been linked to
Multiple organ failure is listed as the most
common cause of death in patients withARDS.7 ARDS is often associated with a sys-
Cardiogenic issues
temic inflammation leading to multiple organ
Hypoxemic issues, which continue after ap-
failure. Treatment of the inciting clinical dis-
plication of support, suggest further cardio-
order is important in the initial management
logic evaluation. When there is doubt about
of ARDS. The diagnostic evaluation should be
the presence of heart failure, right heart
guided by the patient’s history. Evaluation of
catheterization is helpful. Typically, PAWP
a septic source should be done early in pa-
is low (<18 mm Hg) in ARDS, and high
tients deemed septic, looking at pulmonary
(>20 mm Hg) in heart failure.18 Compromise
and extrapulmonary sites of infection. Intra-
in intravascular volume along with positive
abdominal sepsis should be considered early
end-expiratory pressure (PEEP) results in de-
in patients with sepsis syndrome who exhibit
creased cardiac output.29 Sepsis and diuretic
acute lung injury of uncertain etiology.
therapy contribute to relative volume deple-
Several reports have listed that the high-
tion. Despite significant fluid loads within
est incidence of ARDS is associated with sep-
the pulmonary bed, blood volume issues are
sis syndrome and that these patients also
critical. Tissue perfusion and oxygen delivery
reflect adequacy of the cardiopulmonary sta-
prognosis than lung injury induced by other
tus. If this is not maintained, or is interrupted,
mechanisms.7,14 Early evaluation and specific
poor perfusion contributes further to multi-
medical or surgical treatment of the source of
ple organ failure. The range of volume man-
sepsis can enhance the chance of survival.
agement is narrow, as both overhydration and
aggressive diuresis cause significant variation
tein C for appropriate patients will reduce
Adult Respiratory Distress Syndrome
mortality in patients with severe sepsis.33 For
hypercapnia.37,38 Permissive hypercapnia is
other insults, such as aspiration or multiple
an effective strategy for limiting the ventila-
transfusions, care should be focused on pre-
tory pressures by allowing PaCO2 to rise.34 It is
vention of recurrence. Optimal supportive
generally felt that with permissive hypercap-
care is recommended for all acute lung in-
nia, PaCO2 may be kept in the range of 60 to
juries with ARDS due to various causes.
100, and the pH maintained at more than orequal to 7.25 without deleterious effects.
To prevent ventilator-associated injury to
VENTILATION
the lungs, plateau pressures need to be mon-itored with attempts to maintain them at
Mechanical ventilation is the mainstay of
can be achieved by permissive hypercapnia,
quate oxygenation and to stabilize ventilation
pressure-controlled ventilation, and pressure-
(Table 1). Initially, with any form of res-
limited volume cycled ventilation. Another
piratory failure, standard ventilatory strate-
protective ventilation strategy includes an
gies may be utilized, using flow-controlled
“open lung”technique in which PEEP is main-
volume-cycled ventilation, with a tidal volume
tained at a level above where alveoli collapse,
(TV) of 10 to15 mL/kg. In recent years, it has
and the distending pressure and volume is
become more evident that the standard ven-
limited (TV < 6 mL/kg and driving pressures
tilation for patients with ARDS is the use of
small tidal volumes so as to be protective to
permissive hypercapnia, and use of pressure-
the lungs and to prevent ventilator-associated
lung injury.12,34–37 The Acute Respiratory Dis-
PEEP can be used to increase end-expiratory
crease in mortality and a decrease in venti-
leads to improved gas exchange. When oxy-
lator days by using a lower TV of 6 mL/kg
genation requirements increase, a high FiO
and a plateau pressure of less than or equal
may be used for brief periods as a tempo-
rizing measure, with aggressive efforts to at-
in past studies that limited peak airway pres-
sures and reduced overdistention of the lung
(which is generally considered to be safe).
by using low tidal volumes and permissive
PEEP can be increased in an attempt to recruitalveoli by opening previously collapsed alve-
Table 1. Ventilator management goals in
oli and preventing further collapse.34,35 PEEP
decreases intrapulmonary shunt, and there-fore improves arterial oxygenation. Potentialadverse effects of PEEP include a decrease
in cardiac output, increase in dead space, in-
crease in lung volume, and stretch during in-
Plateau pressure ≤ 30 cm H2O (adjust TV as
spiration. The lowest mean airway pressure
that achieves an acceptable level of arterial
oxygenation with a nontoxic FiO2 should be
A retrospective review of 150 patients by
Ensure adequate oxygenation (O2 saturation
Page et al found that with protective venti-
lation (plateau pressure < 30 cm H2O) anda low positive end-expiratory pressure (PEEP
∗TV indicates tidal volume; PEEP, positive end-expiratory
< 10 cm H2O), there was a mortality of only
38%.40 In addition, the major factor associated
CRITICAL CARE NURSING QUARTERLY/OCTOBER–DECEMBER 2004
with the probability of dying was the severity
(HFPPV), which uses 60 to 100 breaths/min;
of circulatory failure. Patients without circula-
high-frequency jet ventilation (HFJV), which
uses 100 to 300 breaths/min; and high-frequency oscillation (HFO), which uses up
ALTERNATIVE VENTILATOR MODES
to 2400 breaths/min. Auscultation of lungsounds is altered with the small tidal volumes
Other alternative ventilator modes for ARDS
at the supra physiologic rate.42 Air movement
include inverse ratio, high-frequency ventila-
is difficult to assess. Therefore, continuous
tion, extracorporeal membrane oxygenation
monitoring of oxygen saturation is necessary
(ECMO), and prone positioning. Inverse ratio
to quickly address changes in oxygenation.
ventilation is a technique that changes the
Frequent ABG analysis and daily chest radio-
time of the respiratory cycle so that inspira-
graphy is indicated. Patients are switched
tion and expiration time are equal or reversed.
back to conventional ventilation when they
Normal inspiratory to expiratory (I/E) ratio is
1:2 in a spontaneously breathing patient with
normal airways. With inverse ratio ventilation,
the I/E ratio changes to 1:1 or even 2:1. The 2
potential benefits are a reduction in peak in-
patients.43,44 Mortality at 30 days was 37%
spiratory pressure (PIP) and an improvement
in the HFO group and 52% in the pressure-
in oxygenation from the prolonged inspira-
control ventilation group. Derdak recommen-
tory time.34,35,37 However, patients do not tol-
ded that a trial of HFO be considered when
erate reversals of I/E ratio well, and require
patients need more than 60% FiO2 and mean
neuromuscular blockade to achieve this type
higher, or PEEP is more than 15 cm H2O and
There is renewed interest in high-frequency
inspiratory plateau pressure cannot be main-
ventilation in an attempt to reduce lung in-
tained at less than or equal to 30 cm H2O.43,44
jury and improve clinical outcomes in ARDS.
Overall, more research needs to be under-
Conventional ventilation with higher tidal
taken to compare HFV and conventional lung-
volumes is associated with potentiating or
protective ventilation, as well as timing of the
causing further lung injury. It is generally felt
that the injuries occur from regional overdis-
tension by excessive end-inspiratory lung
(ECMO) is still in experimental stage, and
volumes related to the uneven distribution
as shown in past studies does not improve
of ventilation, that injury occurs in the small
survival.37 However, techniques and results
and injury occurs with shear force at the
a decrease in complications, and it may be
margins between atelectatic lung units and
appropriate to consider new studies utilizing
aerated units.41 High-frequency ventilation
ECMO. In addition, treatment protocols are
being suggested for ARDS in which combined
higher end-expiratory lung volumes with less
treatment methods are utilized. Ullrich et al
overdistension than conventional ventilation.
Also, the high respiratory rates allow the
of airway pressure control, nitrous oxide
maintenance of normal or near-normal PaCO2
inhalation, prone position, and early triage
levels, despite the small tidal volumes.41 It
of nonresponders to ECMO, and achieved an
limits lung overdistension and prevents cyclic
lung collapse by maintaining end-expiratory
lung volume. The broad classifications of
ing ventilation resulted in improved oxygena-
tion and decreased shunt without an increase
in distending pressures.45,46 Various studies
Adult Respiratory Distress Syndrome
patients.53 Nutritional support should be at-
and oxygenation with use of prone position-
tempted and the enteral route is preferable.
ing for 8 to 12 hours a day.45,46 McAuley et al
Enteral feedings decrease the incidence of gas-
showed progressive improvement in gas ex-
tric colonization with gram-negative bacilli as
change over an 18-hour period and suggest
well as prevent stress ulcers.34 Enteral feed-
further research to address the prone position
ings may also have an effect on the host-
for more prolonged periods.47 The improve-
ment in oxygenation with prone positioning
low-carbohydrate, high-fat enteral formula
may be due to the redistribution of ventilation
containing a combination of fish and bor-
with improved dorsal ventilation, changes in
age oils as well as antioxidants over a 4- to
perfusion, and improvement in ventilation-
7-day period, and showed a significant re-
duction in pulmonary neutrophil recruitment
proves in approximately two thirds of patients
and inflammation, a resultant improvement in
who are positioned prone.46 Protocols for
oxygenation, reduction in ventilator stay in
prone positioning are needed to prevent com-
the ICU, and a reduction in organ failure.54
plications such as development of skin pres-
Further nutritional studies are recommended.
sure sites, extubation, catheter removal, or
Maintaining the elevation of head of bed at 30
worsening oxygenation.48–50 Although prone
degrees can help prevent aspiration.
In ventilator management, it is necessary
to maintain an appropriate level of sedation
mechanical ventilation in past studies, there is
to achieve patient-ventilator synchrony. Most
significant improvement in oxygenation.45–47
patients need sedation or analgesia as well
Further research is recommended utilizing
to improve their comfort level. The use of
paralytic agents or excessive and prolonged
sedation should be limited because of thepotential for complications. Paralytic agents
OTHER SUPPORTIVE MEASURES
may be needed to decrease oxygen consump-tion when a patient is very hypoxemic or
has a reduced cardiovascular reserve. Seda-
prevention of other complications, such as
tion and paralysis may be needed for poorly
nosocomial infections, through the use of ap-
tolerated ventilator settings, such as inverse
propriate techniques. The failure to resolve
ratio ventilation. These agents should be used
and prevent secondary infections is a factor
for the shortest period possible, and the pa-
in mortality.34 Bronchodilators can be use-
tient should be monitored closely to limit
ful in patients with bronchospasm or with
the depth of induced paralysis. In addition, a
markedly increased airflow resistance, to de-
train-of-four monitoring to guide the depth of
crease peak and plateau pressures and to im-
paralysis is the recommended standard of care
prove PaO2.51 Also, they may increase the se-
for patients receiving neuromuscular block-
cretion of surfactant and may even exert an
ing agents. This helps to achieve the minimum
anti-inflammatory effect in the lungs.52 Hemo-
dose of paralytic agent necessary for achiev-
dynamic stability must be maintained for ad-
equate organ perfusion. Changes in bodyposition help to facilitate bronchial hygiene
DEVELOPING TREATMENT OPTIONS
and improved gas exchange, as well as tominimize skin breakdown. Daily management
Nitric oxide in its inhaled form is a potent
should also include prophylaxis for deep vein
selective pulmonary vasodilator that does not
thrombosis as well as stress ulcer prophylaxis.
cause systemic vasodilation. It can improve
Sucralfate has been shown to be useful in
arterial oxygenation in patients with ARDS.
preventing late-onset pneumonia in ventilated
However, in studies examining the effects
CRITICAL CARE NURSING QUARTERLY/OCTOBER–DECEMBER 2004
of inhaled nitric oxide, there was no effect
Mild restrictive patterns are most common.
on mortality or the duration of mechanical
Pulmonary function results are not clearly re-
ventilation.55 It may still be useful in patients
lated to severity and duration of ARDS.60 In
with refractory hypoxemia, but not for rou-
one report of post-ARDS functional status,
tine treatment of ARDS. Further studies are
timed 6-minute walks were used to evaluate
endurance and desaturation. Just 1% of pa-
Corticosteroids are not useful in the acute
tients showed desaturation to 88% with exer-
cise at 1 year post-ARDS.59 Poor functional ca-
been suggested as a treatment in the fibropro-
pacity may be related to muscle weakness and
liferative phase of ARDS when administered
to patients after 7 days of respiratory failure.56
Prolonged administration to these patients re-
survivors reveals significant impairment at the
sulted in associated improvement in lung in-
time of hospital discharge. Reasoning, judg-
jury and reduced mortality. Further investiga-
ment, and memory were all lower at the 3-year
tion is suggested regarding timing and dura-
follow-up as well.61 Patients also reported in-
creased incidence of hallucinations, paranoia,
depressed mood, and personality changes in
carbon-associated ventilation (partial liquid)
follow-up.58 Age-related changes are a diffi-
cult variable to control for, and incidence of
along with other experimental approaches,
ARDS increases 10-fold from the ages of 55
such as surfactant administration with alter-
native delivery techniques to optimize distri-
higher duration of ventilation days and signifi-
bution, still need further investigation.34,35,57
cantly higher mortality; with prolonged func-
Also under study are lipid mediators (pros-
tional recovery time likely linked to underly-
platelet-activating factor inhibitors and recep-
tor antagonists, antiadhesion molecules, and
decline in the past several decades.64,65 Early
clinical detection is difficult, as there are fewmeasurable predictable variables that corre-
OUTCOMES
late initial presentation with eventual mortal-ity. The use of low tidal volumes and per-
ARDS still has significant associated mor-
missive hypercapnia have shown promise in
tality outcomes.58 Cause of death is most
continuing to decrease mortality. Timely nurs-
ing assessment and intervention regarding re-
multiple organ failure. Since the predisposing
sponse to treatment is essential. Research con-
factors are variable, the subsets of survivors
tinues to be focused on multiple avenues of
often are not similar in diagnosis or age.59
treatment options in an attempt to improve
Pulmonary function tests are often reported
outcomes. Supportive care issues are an im-
in follow-up as showing almost complete re-
portant factor in functional outcomes. Critical
turn to normal airflows; however, persistently
care nurses have a valuable role in treatment
decreased diffusion capacities are common.59
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PATENT INFRINGEMENTS AT INTERNATIONAL FAIRS CROSS-BORDER ENFORCEMENT THROUGH BELGIAN SUMMARY PROCEEDINGS IN HER RULING OF 25 MARCH 2005, THE PRESIDENT OF THE BRUSSELS DISTRICT COURT ISSUED A CROSS-BORDER INTERIM INJUNCTION AGAINST TWO COMPANIES, ONE BRAZILIAN AND THE OTHER SOUTH KOREAN, WHICH HAD INFRINGED THE PATENT RIGHTS OF THE GERMAN PHARMACEUTICAL COMPANY ALTANA PHARMA AT AN INTERNATION
N E W P R O D U C T S L.A. bans plastic bags Los Angeles became the largest city in thenation to approve a ban on plastic bags atsupermarkets. On Wednesday, the Los Angeles CityCouncil voted 13-1 to phase out single-useplastic bags over the next 12 months at anestimated 7,500 stores, according toreports. After a year, retailers can charge 10cents for paper bags. The city's programwou