Oncotarget

Clinical Research Papers:

This article has been corrected. Correction in: Oncotarget. 2018; 9:15817.

The outcomes and prognostic factors of acute respiratory failure in the patients 90 years old and over

PDF |  HTML  |  How to cite  |  Order a Reprint

Oncotarget. 2018; 9:7197-7203. https://doi.org/10.18632/oncotarget.24051

Metrics: PDF 414 views  |   HTML 745 views  |   ?  

Wan-Ling Chen, Chin-Ming Chen, Shu-Chen Kung, Ching-Min Wang, Chih-Cheng Lai and Chien-Ming Chao _

Abstract

Wan-Ling Chen1,*, Chin-Ming Chen2,3,*, Shu-Chen Kung1, Ching-Min Wang4, Chih-Cheng Lai5 and Chien-Ming Chao5,6

1Department of Respiratory Therapy, Chi Mei Medical Center, Tainan, Taiwan

2Department of Intensive Care Medicine, Chi Mei Medical Center, Tainan, Taiwan

3Department of Recreation and Health-Care Management, Chia Nan University of Pharmacy and Science, Tainan, Taiwan

4Department of Internal Medicine, Chi Mei Medical Center, Tainan, Taiwan

5Department of Intensive Care Medicine, Chi Mei Medical Center, Tainan, Taiwan

6Department of Nursing, Min-Hwei College of Health Care Management, Tainan, Taiwan

*These authors have contributed equally to this work

Correspondence to:

Chien-Ming Chao, email: ccm870958@yahoo.com.tw

Keywords: aged; 90 and over; mechanical ventilation; outcome; risk factor

Received: July 29, 2017    Accepted: December 24, 2017    Published: January 09, 2018

ABSTRACT

This retrospective cohort study investigated the outcomes and prognostic factors in nonagenarians (patients 90 years old or older) with acute respiratory failure. Between 2006 and 2016, all nonagenarians with acute respiratory failure requiring invasive mechanical ventilation (MV) were enrolled. Outcomes including in-hospital mortality and ventilator dependency were measured. A total of 173 nonagenarians with acute respiratory failure were admitted to the intensive care unit (ICU). A total of 56 patients died during the hospital stay and the rate of in-hospital mortality was 32.4%. Patients with higher APACHE (Acute Physiology and Chronic Health Evaluation) II scores (adjusted odds ratio [OR], 5.91; 95 % CI, 1.55-22.45; p = 0.009, APACHE II scores ≥ 25 vs APACHE II scores < 15), use of vasoactive agent (adjust OR, 2.67; 95% CI, 1.12-6.37; p = 0.03) and more organ dysfunction (adjusted OR, 11.13; 95% CI, 3.38-36.36, p < 0.001; ≥ 3 organ dysfunction vs ≤ 1 organ dysfunction) were more likely to die. Among the 117 survivors, 25 (21.4%) patients became dependent on MV. Female gender (adjusted OR, 3.53; 95% CI, 1.16-10.76, p = 0.027) and poor consciousness level (adjusted OR, 4.98; 95% CI, 1.41-17.58, p = 0.013) were associated with MV dependency. In conclusion, the mortality rate of nonagenarians with acute respiratory failure was high, especially for those with higher APACHE II scores or more organ dysfunction.


The outcomes and prognostic factors of acute respiratory failure in the patients 90 years old and over | Chen | Oncotarget

INTRODUCTION

The aging population is rapidly increasing. The World Health Organization (WHO) estimates that by 2050, 1.5 billion people, representing 16% of the global population, will be 65 years old and older. With the increases in the aging population and patients with multiple comorbidities, more patients will require invasive mechanical ventilator (MV) for management of acute respiratory failure [1-3]. Even if elderly patients survive acute illness, they are at high risk of prolonged MV [4-7]. However, these very elderly patients are near the end of life and many may prefer preserving quality of life rather than prolonging survival [8-10]. Thus, this specific population may be reluctant to accept unnecessary prolongation of life by life-sustaining therapy such as invasive MV [10, 11]. Therefore, a study to investigate the outcomes and prognostic factors in very elderly patients with acute respiratory failure requiring MV is warranted. After the outcomes can be fully understood and with an accurate prognosis, physicians can help patients and their families make the best choice regarding MV. Currently, there is limited information on the outcomes and prognosis in very elderly patients who require invasive MV [12, 13]. The aims of this study were to investigate the outcomes of nonagenarians (patients 90 years old or older) with acute respiratory failure requiring invasive MV and to identify risk factors associated with mortality.

RESULTS

Patient characteristics

During the eleven-year period, a total of 173 nonagenarians with acute respiratory failure using MV were admitted to the ICU. Among them, the mean age of the patients was 92.1 ± 2.2 years (range: 90 -99 years). Women comprised most of the patients (n =92, 53.2%). Most patients were admitted to the medical ICU (n = 126, 72.8%), and the others were admitted to the surgical ICU (47, 27.2%). Sepsis was the most common diagnosis of acute respiratory failure (n = 66, 38.2%), followed by gastrointestinal and hepatobiliary disease (n = 35, 20.2%), respiratory disease (n = 28, 16.2%), cardiovascular disease (n = 19, 11.0%), neurologic disease (n = 13, 7.5%), endocrine disease (n = 2, 1.2%), renal disease (n = 1, 0.6%), and others (n = 9, 5.2%). Hypertension was the most common underlying disease (n = 115, 66.5%), followed by chronic kidney disease (n = 45, 26.0%), stroke (n = 41, 23.7%), diabetes mellitus (n = 39, 22.5%), congestive heart failure (n = 36, 20.8%), chronic obstructive pulmonary disease (n = 35, 20.2%), dementia (n = 26, 15.0%) and malignancy (n = 24, 13.9%). In addition, 33 patients (19.1%) had a recent history of corticosteroid administration. Respiratory dysfunction was the most common organ dysfunction (n = 148, 85.5%), followed by cardiovascular (n = 81, 46.8%), renal (n = 63, 36.4%), liver (n = 21, 12.1%) and hematologic organ dysfunction (n = 12, 6.9%). Dysfunction of at least one organ was found in 155 (89.6%) patients. During ICU hospitalization, seven patients had continuous renal replacement therapy and six patients used intermittent hemodialysis. One patient had an intra-aortic balloon pump for hemodynamic support. Eleven patients received a tracheostomy. Ninety-two (53.2%) patients were successfully weaned from MV, but 25 (14.5%) patients became MV-dependent. The LOS in the ICU and hospital was 8.5 ± 6.8 (median: 8 days, IQR: 3-12) and 24.6±25.4 days (median, 18 days, IQR: 10-33), respectively.

Outcome analysis

A total of 56 patients died during the hospital stay and the rate of in-hospital mortality was 32.4%. We further compared the clinical variables of patients with survived and those who died (Table 1). Patients who died had lower Glasgow coma scores, higher APACHE II scores, more underlying chronic kidney disease, poorer renal function, more frequent use of vasoactive agents and more cardiovascular, hematologic, renal and liver failure than the survivors (Table 1). In contrast, the survivor had more tracheostomy, and shorter length hospital stay (Table 1). Table 2 summarizes the risk factors associated with the in-hospital mortality rate using stepwise logistic regression analysis. Patients with higher APACHE II scores, use of vasoactive agent and more organ dysfunction were more likely to die (Table 2).

Table 1: The comparison of clinical variables between patients with survival and mortality outcomes

Variables

No (%) of patients with survival outcomes
(n=117)

No (%) of patients with mortality outcomes
(n=56)

P value

Age (years)

92.1 ± 2.3

92.0 ± 2.0

0.68

Gender

 Male

54 (46.2)

27 (48.2)

0.80

 Female

63 (53.8)

29 (51.8)

Category of ICU

0.66

 Medical ICU

84 (71.8)

42 (75.0)

 Surgical ICU

33 (28.2)

14 (25.0)

Glasgow Coma Scale

11.0 (9.0-14.0)

7.0 (3.0-11.0)

< 0.001

APACHE II scores

15.0 (12.0-20.0)

24.0 (18.0-34.0)

< 0.001

Comorbidity

 Dementia

21 (17.9)

5 (8.9)

0.12

 Hypertension

82 (70.1)

33 (58.9)

0.15

 COPD

23 (19.7)

12 (21.4)

0.79

 CHF

21 (17.9)

15 (26.8)

0.18

 Stroke

30 (25.6)

11 (19.6)

0.39

 Diabetes mellitus

23 (19.7)

16 (28.6)

0.19

 CKD

24 (20.5)

21 (37.5)

0.017

 Liver cirrhosis

2 (1.7)

3 (5.4)

0.33

 Malignancy

16 (13.7)

8 (14.3)

0.91

 Receiving steroid

24 (20.5)

9 (16.1)

0.49

Laboratory examinations

 BUN (mg/dl)

26.0 (19.0-37.0)

30.5 (19.8-54.3)

0.07

 Creatinine(mg/d)

1.2 (0.9-1.6)

1.6 (1.1-2.4)

0.009

 Hemoglobin (g/dl)

11.2 (9.8-13.1)

10.9 (9.6-12.2)

0.50

 Albumin (g/dl)

2.8 (2.4-3.2)

2.5 (2.2-2.9)

0.053

Requiring hemodialysis

 IHD

4 (3.4)

2 (3.6)

1.0

 CRRT

2 (1.7)

5 (8.9)

0.37

Use of vasoactive agents

24 (20.5)

33 (58.9)

<0.001

Patients received tracheostomy

11 (9.4)

0 (0.0)

0.02

Organ dysfunction

 Respiratory system

96 (82.1)

52 (92.9)

0.059

 Cardiovascular system

31 (26.5)

50 (89.3)

< 0.001

 Hematologic system

1 (0.9)

11 (19.6)

< 0.001

 Renal system

30 (25.6)

33 (58.9)

< 0.001

 Liver system

10 (8.5)

11 (19.6)

0.037

Lengths of ICU stay

8.0 (5.0-12.0)

5.0 (1.3-12.0)

0.06

Lengths of hospital stay

22.0 (13.0-39.5)

8.0 (2.0-23.3)

<0.001

Data expressed as number (%), mean ± standard deviation (SD) or median with interquartile range (IQR).

Abbreviations: ICU, intensive care unit; APACHE II, Acute Physical and Chronic Healthy Evaluation II; COPD, chronic obstructive pulmonary disease; CHF, congestive heart failure; CKD, chronic kidney disease; IHD, intermittent hemodialysis; CRRT, continuous renal replacement therapy.

Table 2: Risk factor of in-hospital mortality

Variable

Crude OR

95% CI

P value

Adjust OR

95% CI

P value

APACHE II score

 < 15

1.00

1.00

 15-24

2.73

1.16-6.4

0.021

2.21

0.79-6.13

0.13

 ≥25

12.00

4.67-30.85

<0.001

5.91

1.55-22.45

0.009

Glasgow Coma Scale

 ≥ 8

1.00

1.00

 < 8

4.39

2.19-8.79

<0.001

1.41

0.49-4.00

0.53

Underlying chronic kidney disease

 No

1.00

1.00

 Yes

2.32

1.15-4.70

0.019

1.42

0.57-3.58

0.45

Vasoactive agent

 No

1.0

1.0

 Yes

5.56

2.77-11.15

<0.001

2.67

1.12-6.37

0.03

Number of organ dysfunction

 ≤ 1

1.00

1.00

 2

4.85

1.76-13.35

0.002

2.90

0.94-8.89

0.06

 ≥3

25.54

8.99-72.54

<0.001

11.13

3.38-36.63

<0.001

Abbreviations: APACHE II, Acute Physical and Chronic Healthy Evaluation II; OR, odds ratio.

Among the 117 survivors, 25 (21.4%) patients became MV-dependent. These patients were more like to be women, have lower Glasgow Coma Scale scores, have higher APACHE II scores, more use of vasoactive agents and more respiratory organ dysfunction than the patients with successful weaning (Table 3). They also had significantly longer LOS in the ICU and hospital than patients with successful weaning. After stepwise logistic regression analysis, we identified two independent risk factors – gender and consciousness level - which were associated with MV dependence. Women had a higher risk of becoming ventilator-dependent than men (adjusted OR, 3.53; 95% CI, 1.16-10.76, p = 0.027). Patients with Glasgow Coma Scale scores < 8 had a higher risk of becoming ventilator-dependent than those with higher scores (adjusted OR, 4.98; 95% CI, 1.41-17.58, p = 0.013).

Table 3: The comparison of clinical variables between patients with successful weaning and mechanical ventilation-dependent

Variables

No (%) of patients with successful weaning
(n=92)

No (%) of patients with MV-dependent
(n=25)

P value

Age (years)

92.0 ± 2.2

92.5 ± 2.5

0.40

Gender

0.012

 Male

48 (52.2)

6 (24.0)

 Female

44 (47.8)

19 (76.0)

Glasgow Coma Scale

12 (10 -14)

9 (6 -10)

< 0.001

APACHE II scores

19 (13 - 30)

16 (13 - 23)

0.013

Comorbidity

 Dementia

17 (18.5)

4 (16.0)

0.78

 Hypertension

63 (68.5)

19 (76.0)

0.47

 COPD

19 (20.7)

4 (16.0)

0.60

 Congestive heart failure

18 (19.6)

3 (12.0)

0.38

 Stroke

21 (22.8)

9 (36.0)

0.18

 Diabetes mellitus

18 (19.6)

5 (20.0)

0.96

 Chronic kidney disease

21 (22.8)

3 (12.0)

0.24

 Liver cirrhosis

1 (1.1)

1 (4.0)

0.38

 Malignancy

13 (14.1)

3 (12.0)

0.78

 Receiving steroid

19 (20.7)

5 (20.0)

0.94

Use of vasoactive agents

15 (16.3)

9 (36.0)

0.03

Organ dysfunction

 Respiratory system

72 (78.3)

24 (96.0)

0.04

 Cardiovascular system

23 (25.0)

8 (32.0)

0.48

 Hematologic system

0 (0.0)

1 (4.0)

0.21

 Renal system

24 (26.1)

6 (24.0)

0.83

 Liver system

8 (8.7)

2 (8.0)

0.91

ICU length of stay (days)

8.0 (4.3 -11.0)

12.0 (8.0 -15.0)

0.002

Length of hospital stay (days)

19.0 (13.0 - 30.0)

45.0 (18.0 - 56.5)

0.001

Data expressed as number (%), mean ± standard deviation (SD) or median with interquartile range (IQR).

Abbreviations: APACHE II, Acute Physical and Chronic Healthy Evaluation II; COPD, chronic obstructive pulmonary disease; ICU, intensive care unit.

DISCUSSION

To the best of our knowledge, this is the first study to investigate the clinical outcomes of nonagenarians with acute respiratory failure and there were several significant findings. First, the outcome of these very elderly patients with acute respiratory failure was poor and the in-hospital mortality rate was high at 32.4%. Similar findings have been noted in several studies with all-cause hospital mortality rates for critically ill patients 80 years old and older admitted to the ICU ranging from 26% to 50% [14-16]. About one-fifth of survivors become ventilator-dependent. In summary, only half of these patients can survive to discharge and be weaned successfully from MV. Because age itself cannot be the only criterion for health care decision-making, information regarding the prognosis of nonagenarians with acute respiratory failure is important for communication between intensivists and patients and their families [17]. If enough information on outcomes can be obtained, communication between physicians and patients and family can be enhanced and decisions about aggressive management or palliative care can be made appropriately for these elderly critical ill patients [17-19].

Second, previous studies [20-22] have shown that APACHE II scores and number of failed organs are independent predictors of hospital outcome among various populations with acute respiratory failure. In this study of very elderly patients, these two risk factors were found to be independently associated with mortality. Among twenty-six of the 39 (66.7%) patients with APACHE II scores≥ 25 died. and 14 of the 16 (87.5%) patients with ≥ 3 dysfunctional organs died. Our findings indicated that higher APACHE II scores and more organ dysfunction resulted in higher mortality. In addition, use of vasoactive agents was found to be associated with in-hospital mortality (adjusted OR, 2.67; 95% CI, 1.12-6.37, p = 0.03) and it suggests that the initial hemodynamic status should be a good indicator of poor outcome among these elderly patients with acute respiratory failure. End of life care should be considered when treating these patients with poor prognoses.

Third, this study also aimed to determine the risk factors for MV dependency in nonagenarians with acute respiratory failure. Poor consciousness level was independently associated with the risk of ventilator dependency. This is a reasonable association, as an unclear consciousness can result in difficult clearance of secretions and difficult airway maintenance. Moreover, the resolution to difficult airway maintenance – tracheostomy- was only performed in 11 (6.4%) patients in this study. All of these reasons can cause ventilator dependence. Additionally, female gender was associated with a higher risk of ventilator dependency than male gender in this study. The gender difference is difficult to explain and requires further investigation.

This study had several limitations. First, only two major outcomes, in-hospital mortality and ventilator-dependency, were measured. We did not assess long- term outcomes or the functional status of patients after discharge. Further study is warranted to investigate these issues. Second, our findings were based on a single institution. Therefore, it may not be generalized to other hospitals or countries. Finally, we did not collect the data regarding the use of sedative and analgesic agents in this study for analysis. However, these variables may be possible confounding factors.

In conclusion, the mortality rate of nonagenarians with acute respiratory failure was high, especially for patients with higher APACHE II scores or more organ dysfunction. In addition, a significant percentage of patients became ventilator-dependent, especially for patients with a poor consciousness level.

MATERIALS AND METHODS

Patients and hospital setting

This study was conducted in the retrospective cohort observation design. Chi Mei Medical Center is a 900-bed regional hospital with 63 intensive care unit (ICU) beds. Between January, 2006 and December, 2016, all patients 90 years old or older with acute respiratory requiring invasive MV were identified. The medical records of all nonagenarians with invasive MV were retrospectively reviewed and the following information was collected: age, gender, the category of ICU, length of stay (LOS) in the ICU and hospital, Acute Physical and Chronic Healthy Evaluation II (APACHE II) score, Glasgow Coma Scale score, serum albumin, hemoglobin, blood urea nitrogen (BUN), and creatinine levels and comorbidities, including dementia, hypertension, chronic obstructive pulmonary disease, congestive heart failure, chronic kidney disease, diabetes mellitus, liver cirrhosis, stroke, and cancer. The main reason for mechanical ventilation was categorized as follows: respiratory disease (including asthma, chronic obstructive pulmonary disease, pneumothorax, hemoptysis, pneumonia, and pleural infections), cardiovascular disease (including acute coronary syndrome, congestive heart failure, cardiogenic shock, arrhythmia, and cardiac arrest), sepsis (including all septic conditions, but excluding pneumonia and pleural infections), gastrointestinal and hepatobiliary disease, neurologic disease (including seizures, intracranial hemorrhage, stroke, and coma), renal disease, endocrine disease, and others (not belonging to the above categories). We used in-hospital mortality as an outcome measurement and it was defined as death due to any cause during hospitalization. In addition, we collect the data of ventilator dependency which was defined if the patients cannot be successfully weaned off mechanical ventilator during this episode of hospitalization (including intensive care unit, respiratory care center, and ward). Data were collected on a routine basis, and the analysis was conducted retrospectively. The study was approved by the institutional review board of Chi Mei Medical Center, and informed consent was waived (10509-L02).

Statistical analysis

Continuous variables including age, Glasgow Coma Scale score, APACHE II score, serum albumin, hemoglobin, BUN, and creatinine levels at admission, LOS, and duration of MV use are expressed as means ± standard deviations or median and interquartile range (IQR) depending on the nature and distribution of the variables. Categorical variables including gender, category of ICU, comorbidity, and organ dysfunction are expressed as count and percentage. Differences in baseline characteristics and clinical variables between the survival and mortality groups were evaluated using Student’s t-test or Manny-Whitney U rank test for continuous variables and Pearson chi-square tests for categorical variables. A multivariable logistic regression model was constructed from baseline characteristics and clinical variables with p-values <0.05 as candidates. To determine the final prediction model, a stepwise model-selection procedure, in which all candidate variables were inserted until non-effects entered or an effect was removed from the backward elimination, was used to examine the association between predictive variables and the mortality rate and MV dependency using odds ratios (OR) with 95% confidence intervals (95% CI). All statistical analyses were conducted using the statistical package SPSS for Windows (Version 19.0, SPSS, Chicago, Il, USA), and a P value <.05 was considered to show statistical significance.

Sponsor’s role

None.

Author contributions

Chih-Cheng Lai: writing the manuscript. Wan-Ling Chen, Chin-Ming Cheng, Shu-Chen Kung, Ching-Min Wang: data collection. Wan-Ling Chen: statistical analysis. Chien-Ming Chao: writing, review and editing the manuscript.

CONFLICTS OF INTEREST

The authors have no financial or any other kind of personal conflicts with this paper.

REFERENCES

1. Needham DM, Bronskill SE, Calinawan JR, Sibbald WJ, Pronovost PJ, Laupacis A. Projected incidence of mechanical ventilation in Ontario to 2026: preparing for the aging baby boomers. Crit Care Med. 2005; 33:574–579.

2. Needham DM, Bronskill SE, Sibbald WJ, Pronovost PJ, Laupacis A. Mechanical ventilation in Ontario, 1992-2000: incidence, survival, and hospital bed utilization of noncardiac surgery adult patients. Crit Care Med. 2004; 32:1504–1509.

3. Petty TL, Lakshminarayan S, Sahn SA, Zwillich CW, Nett LM. Intensive respiratory care unit. Review of ten years’ experience. JAMA. 1975; 233:34–37.

4. Carson SS. Outcomes of prolonged mechanical ventilation. Curr Opin Crit Care. 2006; 12:405–411.

5. Carson SS, Garrett J, Hanson LC, Lanier J, Govert J, Brake MC, Landucci DL, Cox CE, Carey TS. A prognostic model for one-year mortality in patients requiring prolonged mechanical ventilation. Crit Care Med. 2008; 36:2061–2069.

6. Carson SS, Kahn JM, Hough CL, Seeley EJ, White DB, Douglas IS, Cox CE, Caldwell E, Bangdiwala SI, Garrett JM, Rubenfeld GD; ProVent Investigators. A multicenter mortality prediction model for patients receiving prolonged mechanical ventilation. Crit Care Med. 2012; 40:1171–1176.

7. Lai CC, Shieh JM, Chiang SR, Chiang KH, Weng SF, Ho CH, Tseng KL, Cheng KC. The outcomes and prognostic factors of patients requiring prolonged mechanical ventilation. Sci Rep. 2016; 6:28034.

8. Philippart F, Vesin A, Bruel C, Kpodji A, Durand-Gasselin B, Garçon P, Levy-Soussan M, Jagot JL, Calvo-Verjat N, Timsit JF, Misset B, Garrouste-Orgeas M. The ETHICA study (part I): elderly’s thoughts about intensive care unit admission for life-sustaining treatments. Intensive Care Med. 2013; 39:1565–1573.

9. Heyland DK, Barwich D, Pichora D, Dodek P, Lamontagne F, You JJ, Tayler C, Porterfield P, Sinuff T, Simon J; ACCEPT (Advance Care Planning Evaluation in Elderly Patients) Study Team; Canadian Researchers at the End of Life Network (CARENET). Failure to engage hospitalized elderly patients and their families in advance care planning. JAMA Intern Med. 2013; 173:778–787.

10. Heyland D, Cook D, Bagshaw SM, Garland A, Stelfox HT, Mehta S, Dodek P, Kutsogiannis J, Burns K, Muscedere J, Turgeon AF, Fowler R, Jiang X, et al. The very elderly admitted to ICU: a quality finish? Crit Care Med. 2015; 43:1352–1360.

11. Heyland DK, Dodek P, Rocker G, Groll D, Gafni A, Pichora D, Shortt S, Tranmer J, Lazar N, Kutsogiannis J, Lam M; Canadian Researchers End-of-Life Network(CARENET). What matters most in end-of-life care: perceptions of seriously ill patients and their family members. CMAJ. 2006; 174:627–633.

12. Lai CC, Ko SC, Chen CM, Weng SF, Tseng KL, Cheng KC. The outcomes and prognostic factors of the very elderly requiring prolonged mechanical ventilation in a single respiratory care center. Medicine (Baltimore). 2016; 95:e2479.

13. Li Q, Zhang J, Wan X. [Analysis of characteristics and related risk factors of prognosis in elderly and young adult patients with acute respiratory distress syndrome]. [Article in Chinese]. Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2014; 26:794–798.

14. Ball IM, Bagshaw SM, Burns KE, Cook DJ, Day AG, Dodek PM, Kutsogiannis DJ, Mehta S, Muscedere JG, Turgeon AF, Stelfox HT, Wells GA, Stiell IG. Outcomes of elderly critically ill medical and surgical patients: a multicentre cohort study. Can J Anaesth. 2017; 64:260–269.

15. Heyland DK, Garland A, Bagshaw SM, Cook D, Rockwood K, Stelfox HT, Dodek P, Fowler RA, Turgeon AF, Burns K, Muscedere J, Kutsogiannis J, Albert M, et al. Recovery after critical illness in patients aged 80 years or older: a multi-center prospective observational cohort study. Intensive Care Med. 2015; 41:1911–1920.

16. Heyland DK, Dodek P, Mehta S, Cook D, Garland A, Stelfox HT, Bagshaw SM, Kutsogiannis DJ, Burns K, Muscedere J, Turgeon AF, Fowler R, Jiang X, et al. Admission of the very elderly to the intensive care unit: family members’ perspectives on clinical decision-making from a multicenter cohort study. Palliat Med. 2015; 29:324–335.

17. Guidet B, Hodgson E, Feldman C, Paruk F, Lipman J, Koh Y, Vincent JL, Azoulay E, Sprung CL. The durban world congress ethics round table conference report: II. Withholding or withdrawing of treatment in elderly patients admitted to the intensive care unit. J Crit Care. 2014; 29:896–901.

18. Teno JM, Fisher E, Hamel MB, Wu AW, Murphy DJ, Wenger NS, Lynn J, Harrell FE Jr. Decision-making and outcomes of prolonged ICU stays in seriously ill patients. J Am Geriatr Soc. 2000; 48:S70–74.

19. Teno J, Lynn J, Wenger N, Phillips RS, Murphy DP, Connors AF Jr, Desbiens N, Fulkerson W, Bellamy P, Knaus WA. Advance directives for seriously ill hospitalized patients: effectiveness with the patient self-determination act and the SUPPORT intervention. SUPPORT investigators. Study to understand prognoses and preferences for outcomes and risks of treatment. J Am Geriatr Soc. 1997; 45:500–507.

20. Afessa B, Morales IJ, Scanlon PD, Peters SG. Prognostic factors, clinical course, and hospital outcome of patients with chronic obstructive pulmonary disease admitted to an intensive care unit for acute respiratory failure. Crit Care Med. 2002; 30:1610–1615.

21. Lai CC, Sung MI, Ho CH, Liu HH, Chen CM, Chiang SR, Chao CM, Liu WL, Hsing SC, Cheng KC. The prognostic value of N-terminal proB-type natriuretic peptide in patients with acute respiratory distress syndrome. Sci Rep. 2017; 7:44784.

22. Lai CC, Sung MI, Liu HH, Chen CM, Chiang SR, Liu WL, Chao CM, Ho CH, Weng SF, Hsing SC, Cheng KC. The ratio of partial pressure arterial oxygen and fraction of inspired oxygen 1 day after acute respiratory distress syndrome onset can predict the outcomes of involving patients. Medicine (Baltimore). 2016; 95:e3333.


Creative Commons License All site content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 License.
PII: 24051