2004 A Comparison of Albumin and Saline for Fluid Resuscitation in the Intensive Care Unit

 

2004 Noninvasive Positive-Pressure Ventilation for Respiratory Failure after Extubation

 

2004 Higher versus Lower Positive End-Expiratory Pressures in Patients with the Acute Respiratory Distress Syndrome (ALVEOLI)

2005 Incidence and Outcomes of Acute Lung Injury

  

2007 Advanced Life Support for Out-of-Hospital Respiratory Distress

2008 Efficacy and Safety of Epoetin Alfa in Critically Ill Patients

2008 Vasopressin and Epinephrine vs. Epinephrine Alone in Cardiopulmonary Resuscitation

2009 Decontamination of the Digestive Tract and Oropharynx in ICU Patients

2000 Ventilation with Lower Tidal Volumes as Compared with Traditional Tidal Volumes for Acute Lung Injury and the Acute Respiratory Distress Syndrome

N Engl J Med 342:1301, May 4, 2000

The ARDS Network

Background Traditional approaches to mechanical ventilation use tidal volumes of 10 to 15 ml per kilogram of body weight and may cause stretch-induced lung injury in patients with acute lung injury and the acute respiratory distress syndrome. We therefore conducted a trial to determine whether ventilation with lower tidal volumes would improve the clinical outcomes in these patients.

Methods Patients with acute lung injury and the acute respiratory distress syndrome were enrolled in a multicenter, randomized trial. The trial compared traditional ventilation treatment, which involved an initial tidal volume of 12 ml per kilogram of predicted body weight and an airway pressure measured after a 0.5-second pause at the end of inspiration (plateau pressure) of 50 cm of water or less, with ventilation with a lower tidal volume, which involved an initial tidal volume of 6 ml per kilogram of predicted body weight and a plateau pressure of 30 cm of water or less. The first primary outcome was death before a patient was discharged home and was breathing without assistance. The second primary outcome was the number of days without ventilator use from day 1 to day 28.

Results The trial was stopped after the enrollment of 861 patients because mortality was lower in the group treated with lower tidal volumes than in the group treated with traditional tidal volumes (31.0 percent vs. 39.8 percent, P=0.007), and the number of days without ventilator use during the first 28 days after randomization was greater in this group (mean [±SD], 12±11 vs. 10±11; P=0.007). The mean tidal volumes on days 1 to 3 were 6.2±0.8 and 11.8±0.8 ml per kilogram of predicted body weight (P<0.001), respectively, and the mean plateau pressures were 25±6 and 33±8 cm of water (P<0.001), respectively.

Conclusions In patients with acute lung injury and the acute respiratory distress syndrome, mechanical ventilation with a lower tidal volume than is traditionally used results in decreased mortality and increases the number of days without ventilator use.

2008 Intensity of renal support in critically ill patients with acute kidney injury

VA/NIH Acute Renal Failure Trial Network, Palevsky PM, Zhang JH, O'Connor TZ, Chertow GM, Crowley ST, Choudhury D, Finkel K, Kellum JA, Paganini E, Schein RM, Smith MW, Swanson KM, Thompson BT, Vijayan A, Watnick S, Star RA, Peduzzi P.N Engl J Med  2008 Jul 3;359(1):7-20

BACKGROUND: The optimal intensity of renal-replacement therapy in critically ill patients with acute kidney injury is controversial. METHODS: We randomly assigned critically ill patients with acute kidney injury and failure of at least one nonrenal organ or sepsis to receive intensive or less intensive renal-replacement therapy. The primary end point was death from any cause by day 60. In both study groups, hemodynamically stable patients underwent intermittent hemodialysis, and hemodynamically unstable patients underwent continuous venovenous hemodiafiltration or sustained low-efficiency dialysis. Patients receiving the intensive treatment strategy underwent intermittent hemodialysis and sustained low-efficiency dialysis six times per week and continuous venovenous hemodiafiltration at 35 ml per kilogram of body weight per hour; for patients receiving the less-intensive treatment strategy, the corresponding treatments were provided thrice weekly and at 20 ml per kilogram per hour. RESULTS: Baseline characteristics of the 1124 patients in the two groups were similar. The rate of death from any cause by day 60 was 53.6% with intensive therapy and 51.5% with less-intensive therapy (odds ratio, 1.09; 95% confidence interval, 0.86 to 1.40; P=0.47). There was no significant difference between the two groups in the duration of renal-replacement therapy or the rate of recovery of kidney function or nonrenal organ failure. Hypotension during intermittent dialysis occurred in more patients randomly assigned to receive intensive therapy, although the frequency of hemodialysis sessions complicated by hypotension was similar in the two groups. CONCLUSIONS: Intensive renal support in critically ill patients with acute kidney injury did not decrease mortality, improve recovery of kidney function, or reduce the rate of nonrenal organ failure as compared with less-intensive therapy involving a defined dose of intermittent hemodialysis three times per week and continuous renal-replacement therapy at 20 ml per kilogram per hour. (ClinicalTrials.gov number, NCT00076219.)



Correction to The VA/NIH Acute Renal Failure Trial Network, Intensity of Renal Support in Critically Ill Patients with Acute Kidney Injury, N Engl J Med 359(1):7-20 July 3, 2008. NEJM Volume 361:2391 December 10, 2009 Number 24

Intensity of Renal Support in Critically Ill Patients with Acute Kidney Injury . In the Results section, under the subheading "Complications of Therapy" (page 13), the percentages in the second sentence (for hypotension reported as a complication of therapy) should have been 17.4% and 17.7%, respectively, rather than 18.5% and 18.9%. These percentages were also reported in Table 6 in the Supplementary Appendix. The article has been corrected and the Supplementary Appendix replaced at NEJM.org.

2008 Thrombolysis during Resuscitation for Out-of-Hospital Cardiac Arrest

2008 Hydrocortisone therapy for patients with septic shock

N Engl J Med. 2008 Jan 10;358(2):111-24.

Sprung CL, Annane D, Keh D, Moreno R, Singer M, Freivogel K, Weiss YG,
Benbenishty J, Kalenka A, Forst H, Laterre PF, Reinhart K, Cuthbertson BH, Payen
D, Briegel J; CORTICUS Study Group.

Hadassah Hebrew University Medical Center, Jerusalem, Israel 91120.
This email address is being protected from spambots. You need JavaScript enabled to view it.

BACKGROUND: Hydrocortisone is widely used in patients with septic shock even
though a survival benefit has been reported only in patients who remained
hypotensive after fluid and vasopressor resuscitation and whose plasma cortisol
levels did not rise appropriately after the administration of corticotropin.
METHODS: In this multicenter, randomized, double-blind, placebo-controlled trial,
we assigned 251 patients to receive 50 mg of intravenous hydrocortisone and 248
patients to receive placebo every 6 hours for 5 days; the dose was then tapered
during a 6-day period. At 28 days, the primary outcome was death among patients
who did not have a response to a corticotropin test. RESULTS: Of the 499 patients
in the study, 233 (46.7%) did not have a response to corticotropin (125 in the
hydrocortisone group and 108 in the placebo group). At 28 days, there was no
significant difference in mortality between patients in the two study groups who
did not have a response to corticotropin (39.2% in the hydrocortisone group and
36.1% in the placebo group, P=0.69) or between those who had a response to
corticotropin (28.8% in the hydrocortisone group and 28.7% in the placebo group,
P=1.00). At 28 days, 86 of 251 patients in the hydrocortisone group (34.3%) and
78 of 248 patients in the placebo group (31.5%) had died (P=0.51). In the
hydrocortisone group, shock was reversed more quickly than in the placebo group.
However, there were more episodes of superinfection, including new sepsis and
septic shock. CONCLUSIONS: Hydrocortisone did not improve survival or reversal of
shock in patients with septic shock, either overall or in patients who did not
have a response to corticotropin, although hydrocortisone hastened reversal of
shock in patients in whom shock was reversed. (ClinicalTrials.gov number,
NCT00147004.) 2008 Massachusetts Medical Society

2008 Intensive insulin therapy and pentastarch resuscitation in severe sepsis

N Engl J Med. 2008 Jan 10;358(2):125-39.

Brunkhorst FM, Engel C, Bloos F, Meier-Hellmann A, Ragaller M, Weiler N, Moerer
O, Gruendling M, Oppert M, Grond S, Olthoff D, Jaschinski U, John S, Rossaint R,
Welte T, Schaefer M, Kern P, Kuhnt E, Kiehntopf M, Hartog C, Natanson C, Loeffler
M, Reinhart K; German Competence Network Sepsis (SepNet).

Department of Anesthesiology and Intensive Care Medicine, Friedrich Schiller
University, Jena, Germany.

BACKGROUND: The role of intensive insulin therapy in patients with severe sepsis
is uncertain. Fluid resuscitation improves survival among patients with septic
shock, but evidence is lacking to support the choice of either crystalloids or
colloids. METHODS: In a multicenter, two-by-two factorial trial, we randomly
assigned patients with severe sepsis to receive either intensive insulin therapy
to maintain euglycemia or conventional insulin therapy and either 10%
pentastarch, a low-molecular-weight hydroxyethyl starch (HES 200/0.5), or
modified Ringer's lactate for fluid resuscitation. The rate of death at 28 days
and the mean score for organ failure were coprimary end points. RESULTS: The
trial was stopped early for safety reasons. Among 537 patients who could be
evaluated, the mean morning blood glucose level was lower in the
intensive-therapy group (112 mg per deciliter [6.2 mmol per liter]) than in the
conventional-therapy group (151 mg per deciliter [8.4 mmol per liter], P<0.001).
However, at 28 days, there was no significant difference between the two groups
in the rate of death or the mean score for organ failure. The rate of severe
hypoglycemia (glucose level, < or = 40 mg per deciliter [2.2 mmol per liter]) was
higher in the intensive-therapy group than in the conventional-therapy group
(17.0% vs. 4.1%, P<0.001), as was the rate of serious adverse events (10.9% vs.
5.2%, P=0.01). HES therapy was associated with higher rates of acute renal
failure and renal-replacement therapy than was Ringer's lactate. CONCLUSIONS: The
use of intensive insulin therapy placed critically ill patients with sepsis at
increased risk for serious adverse events related to hypoglycemia. As used in
this study, HES was harmful, and its toxicity increased with accumulating doses.
(ClinicalTrials.gov number, NCT00135473.) 2008 Massachusetts Medical Society

2008 Vasopressin versus norepinephrine infusion in patients with septic shock

N Engl J Med. 2008 Feb 28;358(9):877-87.

Russell JA, Walley KR, Singer J, Gordon AC, Hébert PC, Cooper DJ, Holmes CL,
Mehta S, Granton JT, Storms MM, Cook DJ, Presneill JJ, Ayers D; VASST
Investigators.

iCAPTURE Centre, Vancouver, BC, Canada. This email address is being protected from spambots. You need JavaScript enabled to view it.

BACKGROUND: Vasopressin is commonly used as an adjunct to catecholamines to
support blood pressure in refractory septic shock, but its effect on mortality is
unknown. We hypothesized that low-dose vasopressin as compared with
norepinephrine would decrease mortality among patients with septic shock who were
being treated with conventional (catecholamine) vasopressors. METHODS: In this
multicenter, randomized, double-blind trial, we assigned patients who had septic
shock and were receiving a minimum of 5 microg of norepinephrine per minute to
receive either low-dose vasopressin (0.01 to 0.03 U per minute) or norepinephrine
(5 to 15 microg per minute) in addition to open-label vasopressors. All
vasopressor infusions were titrated and tapered according to protocols to
maintain a target blood pressure. The primary end point was the mortality rate 28
days after the start of infusions. RESULTS: A total of 778 patients underwent
randomization, were infused with the study drug (396 patients received
vasopressin, and 382 norepinephrine), and were included in the analysis. There
was no significant difference between the vasopressin and norepinephrine groups
in the 28-day mortality rate (35.4% and 39.3%, respectively; P=0.26) or in 90-day
mortality (43.9% and 49.6%, respectively; P=0.11). There were no significant
differences in the overall rates of serious adverse events (10.3% and 10.5%,
respectively; P=1.00). In the prospectively defined stratum of less severe septic
shock, the mortality rate was lower in the vasopressin group than in the
norepinephrine group at 28 days (26.5% vs. 35.7%, P=0.05); in the stratum of more
severe septic shock, there was no significant difference in 28-day mortality
(44.0% and 42.5%, respectively; P=0.76). A test for heterogeneity between these
two study strata was not significant (P=0.10). CONCLUSIONS: Low-dose vasopressin
did not reduce mortality rates as compared with norepinephrine among patients
with septic shock who were treated with catecholamine vasopressors. (Current
Controlled Trials number, ISRCTN94845869 [controlled-trials.com].). Copyright
2008 Massachusetts Medical Society.

2006 Intensive insulin therapy in the medical ICU

N Engl J Med. 2006 Feb 2;354(5):449-61.

Van den Berghe G, Wilmer A, Hermans G, Meersseman W, Wouters PJ, Milants I, Van
Wijngaerden E, Bobbaers H, Bouillon R.

Department of Intensive Care Medicine, Catholic University of Leuven, Leuven,
Belgium. This email address is being protected from spambots. You need JavaScript enabled to view it.

BACKGROUND: Intensive insulin therapy reduces morbidity and mortality in patients
in surgical intensive care units (ICUs), but its role in patients in medical ICUs
is unknown. METHODS: In a prospective, randomized, controlled study of adult
patients admitted to our medical ICU, we studied patients who were considered to
need intensive care for at least three days. On admission, patients were randomly
assigned to strict normalization of blood glucose levels (80 to 110 mg per
deciliter [4.4 to 6.1 mmol per liter]) with the use of insulin infusion or to
conventional therapy (insulin administered when the blood glucose level exceeded
215 mg per deciliter [12 mmol per liter], with the infusion tapered when the
level fell below 180 mg per deciliter [10 mmol per liter]). There was a history
of diabetes in 16.9 percent of the patients. RESULTS: In the intention-to-treat
analysis of 1200 patients, intensive insulin therapy reduced blood glucose levels
but did not significantly reduce in-hospital mortality (40.0 percent in the
conventional-treatment group vs. 37.3 percent in the intensive-treatment group,
P=0.33). However, morbidity was significantly reduced by the prevention of newly
acquired kidney injury, accelerated weaning from mechanical ventilation, and
accelerated discharge from the ICU and the hospital. Although length of stay in
the ICU could not be predicted on admission, among 433 patients who stayed in the
ICU for less than three days, mortality was greater among those receiving
intensive insulin therapy. In contrast, among 767 patients who stayed in the ICU
for three or more days, in-hospital mortality in the 386 who received intensive
insulin therapy was reduced from 52.5 to 43.0 percent (P=0.009) and morbidity was
also reduced. CONCLUSIONS: Intensive insulin therapy significantly reduced
morbidity but not mortality among all patients in the medical ICU. Although the
risk of subsequent death and disease was reduced in patients treated for three or
more days, these patients could not be identified before therapy. Further studies
are needed to confirm these preliminary data. (ClinicalTrials.gov number,
NCT00115479.) Copyright 2006 Massachusetts Medical Society.

2006 Hospital volume and the outcomes of mechanical ventilation

N Engl J Med. 2006 Jul 6;355(1):41-50.

Kahn JM, Goss CH, Heagerty PJ, Kramer AA, O'Brien CR, Rubenfeld GD.

Division of Pulmonary and Critical Care Medicine, University of Washington,
Seattle 98104, USA.

BACKGROUND: An increased volume of patients is associated with improved survival
in numerous high-risk medical and surgical conditions. The relationship between
the number of patients admitted (hospital volume) and outcome among patients with
critical illnesses is unknown. METHODS: We analyzed data from 20,241 nonsurgical
patients receiving mechanical ventilation at 37 acute care hospitals in the Acute
Physiology and Chronic Health Evaluation clinical information system from 2002
through 2003. Multivariate analyses were performed to adjust for the severity of
illness and other differences in the case mix. RESULTS: An increase in hospital
volume was associated with improved survival among patients receiving mechanical
ventilation in the intensive care unit (ICU) and in the hospital. Admission to a
hospital in the highest quartile according to volume (i.e., >400 patients
receiving mechanical ventilation per year) was associated with a 37 percent
reduction in the adjusted odds of death in the ICU as compared with admission to
hospitals in the lowest quartile (< or =150 patients receiving mechanical
ventilation per year, P<0.001). In-hospital mortality was similarly reduced
(adjusted odds ratio, 0.66; 95 percent confidence interval, 0.52 to 0.83;
P<0.001). A typical patient in a hospital in a low-volume quartile would have an
adjusted in-hospital mortality of 34.2 percent as compared with 25.5 percent in a
hospital in a high-volume quartile. Among survivors, there were no significant
trends in the length of stay in the ICU or the hospital. CONCLUSIONS: Mechanical
ventilation of patients in a hospital with a high case volume is associated with
reduced mortality. Further research is needed to determine the mechanism of the
relationship between volume and outcome among patients with a critical illness.
Copyright 2006 Massachusetts Medical Society.

2006 A randomized trial of diagnostic techniques for ventilator-associated pneumonia

N Engl J Med. 2006 Dec 21;355(25):2619-30.

Canadian Critical Care Trials Group.

BACKGROUND: Critically ill patients who require mechanical ventilation are at
risk for ventilator-associated pneumonia. Current data are conflicting as to the
optimal diagnostic approach in patients who have suspected ventilator-associated
pneumonia. METHODS: In a multicenter trial, we randomly assigned immunocompetent
adults who were receiving mechanical ventilation and who had suspected
ventilator-associated pneumonia after 4 days in the intensive care unit (ICU) to
undergo either bronchoalveolar lavage with quantitative culture of the
bronchoalveolar-lavage fluid or endotracheal aspiration with nonquantitative
culture of the aspirate. Patients known to be colonized or infected with
pseudomonas species or methicillin-resistant Staphylococcus aureus were excluded.
Empirical antibiotic therapy was initiated in all patients until culture results
were available, at which point a protocol of targeted therapy was used for
discontinuing or reducing the dose or number of antibiotics, or for resuming
antibiotic therapy to treat a preenrollment condition if the culture was
negative. RESULTS: We enrolled 740 patients in 28 ICUs in Canada and the United
States. There was no significant difference in the primary outcome (28-day
mortality rate) between the bronchoalveolar-lavage group and the
endotracheal-aspiration group (18.9% and 18.4%, respectively; P=0.94). The
bronchoalveolar-lavage group and the endotracheal-aspiration group also had
similar rates of targeted therapy (74.2% and 74.6%, respectively; P=0.90), days
alive without antibiotics (10.4+/-7.5 and 10.6+/-7.9, P=0.86), and maximum
organ-dysfunction scores (mean [+/-SD], 8.3+/-3.6 and 8.6+/-4.0; P=0.26). The two
groups did not differ significantly in the length of stay in the ICU or hospital.
CONCLUSIONS: Two diagnostic strategies for ventilator-associated
pneumonia--bronchoalveolar lavage with quantitative culture of the
bronchoalveolar-lavage fluid and endotracheal aspiration with nonquantitative
culture of the aspirate--are associated with similar clinical outcomes and
similar overall use of antibiotics. (Current Controlled Trials number,
ISRCTN51767272 [controlled-trials.com].). Copyright 2006 Massachusetts Medical
Society.

2006 An intervention to decrease catheter-related bloodstream infections in the ICU

N Engl J Med. 2006 Dec 28;355(26):2725-32.

Erratum in:
    N Engl J Med. 2007 Jun 21;356(25):2660.

Pronovost P, Needham D, Berenholtz S, Sinopoli D, Chu H, Cosgrove S, Sexton B,
Hyzy R, Welsh R, Roth G, Bander J, Kepros J, Goeschel C.

School of Medicine, Johns Hopkins University, Baltimore, USA

BACKGROUND: Catheter-related bloodstream infections occurring in the intensive
care unit (ICU) are common, costly, and potentially lethal. METHODS: We conducted
a collaborative cohort study predominantly in ICUs in Michigan. An evidence-based
intervention was used to reduce the incidence of catheter-related bloodstream
infections. Multilevel Poisson regression modeling was used to compare infection
rates before, during, and up to 18 months after implementation of the study
intervention. Rates of infection per 1000 catheter-days were measured at 3-month
intervals, according to the guidelines of the National Nosocomial Infections
Surveillance System. RESULTS: A total of 108 ICUs agreed to participate in the
study, and 103 reported data. The analysis included 1981 ICU-months of data and
375,757 catheter-days. The median rate of catheter-related bloodstream infection
per 1000 catheter-days decreased from 2.7 infections at baseline to 0 at 3 months
after implementation of the study intervention (P< or =0.002), and the mean rate
per 1000 catheter-days decreased from 7.7 at baseline to 1.4 at 16 to 18 months
of follow-up (P<0.002). The regression model showed a significant decrease in
infection rates from baseline, with incidence-rate ratios continuously decreasing
from 0.62 (95% confidence interval [CI], 0.47 to 0.81) at 0 to 3 months after
implementation of the intervention to 0.34 (95% CI, 0.23 to 0.50) at 16 to 18
months. CONCLUSIONS: An evidence-based intervention resulted in a large and
sustained reduction (up to 66%) in rates of catheter-related bloodstream
infection that was maintained throughout the 18-month study period. Copyright
2006 Massachusetts Medical Society.

2007 A communication strategy and brochure for relatives of patients dying in the ICU

N Engl J Med. 2007 Feb 1;356(5):469-78.

Erratum in:
    N Engl J Med. 2007 Jul 12;357(2):203.

Lautrette A, Darmon M, Megarbane B, Joly LM, Chevret S, Adrie C, Barnoud D,
Bleichner G, Bruel C, Choukroun G, Curtis JR, Fieux F, Galliot R,
Garrouste-Orgeas M, Georges H, Goldgran-Toledano D, Jourdain M, Loubert G,
Reignier J, Saidi F, Souweine B, Vincent F, Barnes NK, Pochard F, Schlemmer B,
Azoulay E.

Saint-Louis Hospital and Paris 7 University, Assistance Publique-Hôpitaux de
Paris, France.

BACKGROUND: There is a need for close communication with relatives of patients
dying in the intensive care unit (ICU). We evaluated a format that included a
proactive end-of-life conference and a brochure to see whether it could lessen
the effects of bereavement. METHODS: Family members of 126 patients dying in 22
ICUs in France were randomly assigned to the intervention format or to the
customary end-of-life conference. Participants were interviewed by telephone 90
days after the death with the use of the Impact of Event Scale (IES; scores range
from 0, indicating no symptoms, to 75, indicating severe symptoms related to
post-traumatic stress disorder [PTSD]) and the Hospital Anxiety and Depression
Scale (HADS; subscale scores range from 0, indicating no distress, to 21,
indicating maximum distress). RESULTS: Participants in the intervention group had
longer conferences than those in the control group (median, 30 minutes
[interquartile range, 19 to 45] vs. 20 minutes [interquartile range, 15 to 30];
P<0.001) and spent more of the time talking (median, 14 minutes [interquartile
range, 8 to 20] vs. 5 minutes [interquartile range, 5 to 10]). On day 90, the 56
participants in the intervention group who responded to the telephone interview
had a significantly lower median IES score than the 52 participants in the
control group (27 vs. 39, P=0.02) and a lower prevalence of PTSD-related symptoms
(45% vs. 69%, P=0.01). The median HADS score was also lower in the intervention
group (11, vs. 17 in the control group; P=0.004), and symptoms of both anxiety
and depression were less prevalent (anxiety, 45% vs. 67%; P=0.02; depression, 29%
vs. 56%; P=0.003). CONCLUSIONS: Providing relatives of patients who are dying in
the ICU with a brochure on bereavement and using a proactive communication
strategy that includes longer conferences and more time for family members to
talk may lessen the burden of bereavement. (ClinicalTrials.gov number,
NCT00331877.) 2007 Massachusetts Medical Society

2006 Lung recruitment in patients with the acute respiratory distress syndrome

N Engl J Med. 2006 Apr 27;354(17):1775-86.

Gattinoni L, Caironi P, Cressoni M, Chiumello D, Ranieri VM, Quintel M, Russo S,
Patroniti N, Cornejo R, Bugedo G.

Istituto di Anestesiologia e Rianimazione, Fondazione Istituto di Ricovero e Cura
a Carattere Scientifico, Ospedale Maggiore Policlinico, Mangiagalli, Regina Elena
di Milano, Università degli Studi di Milano, Milan, Italy.
This email address is being protected from spambots. You need JavaScript enabled to view it.

BACKGROUND: In the acute respiratory distress syndrome (ARDS), positive
end-expiratory pressure (PEEP) may decrease ventilator-induced lung injury by
keeping lung regions open that otherwise would be collapsed. Since the effects of
PEEP probably depend on the recruitability of lung tissue, we conducted a study
to examine the relationship between the percentage of potentially recruitable
lung, as indicated by computed tomography (CT), and the clinical and
physiological effects of PEEP. METHODS: Sixty-eight patients with acute lung
injury or ARDS underwent whole-lung CT during breath-holding sessions at airway
pressures of 5, 15, and 45 cm of water. The percentage of potentially recruitable
lung was defined as the proportion of lung tissue in which aeration was restored
at airway pressures between 5 and 45 cm of water. RESULTS: The percentage of
potentially recruitable lung varied widely in the population, accounting for a
mean (+/-SD) of 13+/-11 percent of the lung weight, and was highly correlated
with the percentage of lung tissue in which aeration was maintained after the
application of PEEP (r2=0.72, P<0.001). On average, 24 percent of the lung could
not be recruited. Patients with a higher percentage of potentially recruitable
lung (greater than the median value of 9 percent) had greater total lung weights
(P<0.001), poorer oxygenation (defined as a ratio of partial pressure of arterial
oxygen to fraction of inspired oxygen) (P<0.001) and respiratory-system
compliance (P=0.002), higher levels of dead space (P=0.002), and higher rates of
death (P=0.02) than patients with a lower percentage of potentially recruitable
lung. The combined physiological variables predicted, with a sensitivity of 71
percent and a specificity of 59 percent, whether a patient's proportion of
potentially recruitable lung was higher or lower than the median. CONCLUSIONS: In
ARDS, the percentage of potentially recruitable lung is extremely variable and is
strongly associated with the response to PEEP. Copyright 2006 Massachusetts
Medical Society.