2-Month Mortality and Functional Status of Critically Ill Adult Patients Receiving Prolonged Mechanical Ventilation

doi:10.1378/chest.121.2.549

Chest

Volume 121, Issue 2, February 2002, Pages 549-558

https://doi.org/10.1378/chest.121.2.549 Get rights and content

Study objectives

To describe the 2-month mortality and functional status of adult patients receiving prolonged (at least 48 h) mechanical ventilation (MV), and to identify patient characteristics that are associated with 2-month mortality.

Design

Prospective cohort study.

Setting

Four ICUs at a tertiary-care institution.

Patients

Eight hundred seventeen patients who received prolonged MV.

Interventions

None.

Measurements and results

Median age, sex distribution, and median Charlson comorbidity score of the 817 patients were 65 years, 45.8% women, and 1, respectively. The median scores on Katz Activities of Daily Living, Instrumental Activities of Daily Living Deficits, and Medical Outcomes Study Short-Form 36 surveys before hospitalization were 0, 1, and 50, respectively. Median APACHE (acute physiology and chronic health evaluation) III score and probability of hospital death for the cohort were 64 and 0.31, respectively. Median duration of MV was 9 days. Two-month mortality was 43%. Independent predictors of mortality at 2 months were age, comorbidities, and prehospital functional status. The adjusted odds of dying within 2 months increased 34% for each decade increase in age. Functional status deteriorated at 2 months compared to functional status prior to hospitalization, and 35% of the survivors were at risk for clinical depression. Among the 2-month survivors for whom the need for a caregiver was assessed, 78% had a caregiver.

Conclusions

Older age, in addition to functional status and comorbidities, was associated with increased mortality at 2 months. Functional status of survivors declined at 2 months.

Section snippets

Study Site and Patient Selection

The Quality of Life After Mechanical Ventilation in the Aged (QOL-MV) study was conducted at the University of Pittsburgh Medical Center (UPMC) Health System, a tertiary-care facility. QOL-MV subjects were recruited from the medical, neurologic, trauma, and general surgical ICUs at the UPMC. QOL-MV is a study evaluating long-term (1 year) mortality and functional status of patients receiving prolonged MV. In this article, we report outcome at 2 months.

During a recruitment period beginning in

Study Sample and Baseline Characteristics

During the recruitment period, 2,237 patients received 2,557 episodes of MV in the study ICUs (Fig 1). Of the 2,237 patients, 1,123 patients (50.2%) received MV for ≥48 h. Two hundred twenty-nine patients were excluded because they had pretransplantation or posttransplantation status, were chronically ventilator dependent, were intubated for 24 h prior to ICU admission, or did not speak English. Of the remaining 894 patients, 77 patients or their families refused to participate in the study.

Mortality

Patients receiving MV for any duration in an ICU have higher in-hospital mortality than patients who do not need MV support. The reported duration of MV prior to inclusion in different studies has varied from a few hours to 2 to 3 days. Hospital mortality was reported to vary from 50 to 67% in a review by Stauffer et al⁶ in 1993. Other studies⁵¹⁰¹¹²²²³ report in-hospital mortality ranging from 23 to 43%. The differences in these studies may be due to different inclusion criteria resulting in

Conclusion

This prospective study of a large cohort of patients receiving MV demonstrates that age and functional status prior to hospitalization are factors predictive of mortality at 2 months. Such information may be useful in analyzing future trials of treatment effectiveness and in discussing goals of therapy for patients receiving prolonged MV. In addition, since family and caregiver support, as well as the patient functional and psychological status, play a major role in survivor quality-of-life

Appendix

The QOL-MV Study Investigators are Lakshmipathi Chelluri, MD, MPH, FCCP, Armando J. Rotondi, PhD, Carl A. Sirio, MD, Michael P. Donahoe, MD, and Micheal R. Pinsky, MD, University of Pittsburgh School of Medicine; Aaron B. Mendelsohn, PhD, and Steven H. Belle, PhD, Graduate School of Public Health; and Richard Schulz, PhD, University Center for Social and Urban Research, University of Pittsburgh, Pittsburgh, PA.

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Cited by (62)

Nebulised heparin for patients with or at risk of acute respiratory distress syndrome: a multicentre, randomised, double-blind, placebo-controlled phase 3 trial
2021, The Lancet Respiratory Medicine
Citation Excerpt :
ARDS affects 23% of mechanically ventilated, critically ill patients and has a mortality of up to 46%.2,3 Survivors of prolonged mechanical ventilation and ARDS have marked limitations in physical function, are more often readmitted to hospital, and have greater need of rehabilitation services and long-term care than those who required less than 48 h of mechanical ventilation.4–9 Considerable physical limitations persist at 5 years after diagnosis and include difficulty undertaking basic activities, such as walking, bathing, and dressing.10
Mechanical ventilation in intensive care for 48 h or longer is associated with the acute respiratory distress syndrome (ARDS), which might be present at the time ventilatory support is instituted or develop afterwards, predominantly during the first 5 days. Survivors of prolonged mechanical ventilation and ARDS are at risk of considerably impaired physical function that can persist for years. An early pathogenic mechanism of lung injury in mechanically ventilated, critically ill patients is inflammation-induced pulmonary fibrin deposition, leading to thrombosis of the microvasculature and hyaline membrane formation in the air sacs. The main aim of this study was to determine if nebulised heparin, which targets fibrin deposition, would limit lung injury and thereby accelerate recovery of physical function in patients with or at risk of ARDS.
The Can Heparin Administration Reduce Lung Injury (CHARLI) study was an investigator-initiated, multicentre, double-blind, randomised phase 3 trial across nine hospitals in Australia. Adult intensive care patients on invasive ventilation, with impaired oxygenation defined by a PaO₂/FiO₂ ratio of less than 300, and with the expectation of invasive ventilation beyond the next calendar day were recruited. Key exclusion criteria were heparin allergy, pulmonary bleeding, and platelet count less than 50 X 10⁹/L. Patients were randomly assigned 1:1, with stratification by site and using blocks of variable size and random seed, via a web-based system, to either unfractionated heparin sodium 25 000 IU in 5 mL or identical placebo (sodium chloride 0·9% 5 mL), administered using a vibrating mesh membrane nebuliser every 6 h to day 10 while invasively ventilated. Patients, clinicians, and investigators were masked to treatment allocation. The primary outcome was the Short Form 36 Health Survey Physical Function Score (out of 100) of survivors at day 60. Prespecified secondary outcomes, which are exploratory, included development of ARDS to day 5 among at-risk patients, deterioration of the Murray Lung Injury Score (MLIS) to day 5, mortality at day 60, residence of survivors at day 60, and serious adverse events. Analyses followed the intention-to-treat principle. There was no imputation of missing data. The trial is registered with the Australian and New Zealand Clinical Trials Register, number ACTRN12612000418875 .
Between Sept 4, 2012, and Aug 23, 2018, 256 patients were randomised. Final follow-up was on Feb 25, 2019. We excluded three patients who revoked consent and one ineligible participant who received no intervention. Of 252 patients included in data analysis, the mean age was 58 years (SD 15), 157 (62%) were men, and 118 (47%) had ARDS. 128 (51%) patients were assigned to the heparin group and 124 (49%) to the placebo group, all of whom received their assigned intervention. Survivors in the heparin group (n=97) had similar SF-36 Physical Function Scores at day 60 compared to the placebo group (n=94; mean 53·6 [SD 31·6] vs 48·7 [35·7]; difference 4·9 [95% CI −4·8 to 14·5]; p=0·32). Compared with the placebo group, the heparin group had fewer cases of ARDS develop to day 5 among the at-risk patients (nine [15%] of 62 patients vs 21 [30%] of 71 patients; hazard ratio 0·46 [95% CI 0·22 to 0·98]; p=0·0431), less deterioration of the MLIS to day 5 (difference −0·14 [–0·26 to −0·02]; p=0·0215), similar day 60 mortality (23 [18%] of 127 patients vs 18 [15%] of 123 patients; odds ratio [OR] 1·29 [95% CI 0·66 to 2·53]; p=0·46), and more day 60 survivors at home (86 [87%] of 99 patients vs 73 [73%] of 100 patients; OR 2·45 [1·18 to 5·08]; p=0·0165). A similar number of serious adverse events occurred in each group (seven [5%] of 128 patients in the heparin group vs three [2%] of 124 patients in the placebo group; OR 2·33 [0·59 to 9·24]; p=0·23), which were a transient increase in airway pressure during nebulisation (n=3 in the heparin group), major non-pulmonary bleeding (n=2 in each group), haemoptysis (n=1 in the heparin group), tracheotomy site bleeding (n=1 in the heparin group), and hypoxaemia during nebulisation (n=1 in the placebo group).
In patients with or at risk of ARDS, nebulised heparin did not improve self-reported performance of daily physical activities, but was well tolerated and exploratory outcomes suggest less progression of lung injury and earlier return home. Further research is justified to establish if nebulised heparin accelerates recovery in those who have or are at risk of ARDS.
Rowe Family Foundation, TR and RB Ditchfield Medical Research Endowment Fund, Patricia Madigan Charitable Trust, and The J and R McGauran Trust Fund.
Early vs. late tracheostomy in intensive care settings: Impact on ICU and hospital costs
2018, Journal of Critical Care
Up to 12% of the 800,000 patients who undergo mechanical ventilation in the United States every year require tracheostomies. A recent systematic review showed that early tracheostomy was associated with better outcomes: more ventilator-free days, shorter ICU stays, less sedation and reduced long-term mortality. However, the financial impact of early tracheostomies remain unknown.
To conduct a cost-analysis on the timing of tracheostomy in mechanically ventilated patients.
We extracted individual length of hospital stay and length of ICU stay data from the studies included in the systematic review from Hosokawa et al. We also searched for any recent randomized control trials on the topic that were published after this review. The weighted length of stay was estimated using a random effects model. Average daily hospital and ICU costs per patients were obtained from a cost study by Kahn et al. We estimated hospital and ICU costs by multiplying LOS with respective average daily cost per patient. We calculated difference in costs by subtracting hospital costs, ICU costs and total direct variable costs from early tracheotomy to late tracheotomy. 95% confidence intervals were estimated using bootstrap re-sampling procedures with 1000 iterations.
The average weighted cost of ICU stay in patients with an early tracheostomy was $4316 less when compared to patients with late tracheostomy (95% CI: 403–8229). Subgroup analysis revealed that very early tracheostomies (< 4 days) cost on average $3672 USD less than late tracheostomies (95% CI: –1309, 10,294) and that early tracheostomies (< 10 days but > 4) cost on average $6385 USD less than late tracheostomies (95% CI: –4396–17,165).
This study shows that early tracheostomy can significantly reduce direct variable and likely total hospital costs in the intensive care unit based on length of stay alone. This is in addition to the already shown benefits of early tracheostomy in terms of ventilator dependent days, reduced length of stays, decreased pain, and improved communication. Further prospective studies on this topic are needed to prove the cost-effectiveness of early tracheostomy in the critically ill population.
Predictors of mortality of mechanically ventilated patients in internal medicine wards
2012, Journal of Critical Care
Citation Excerpt :
In this study, APS above certain values predicted substantially increased mortality rates in this non-ICU group of ventilated patients. Conversely, a high Charlson index or a poor ADL score was not associated with increased mortality, in contrast with previous studies showing that both the burden of comorbidity [25-27] and the degree of functional independence [14] predict survival in critically ill, although mainly ICU ventilated patients. This inconsistency may stem from the sample size.
Budget restrictions have led to shortage of intensive care unit (ICU) beds in several countries. Consequently, ventilated patients are often kept on the wards. This study examined survival likelihood among patients ventilated on the wards and the predictive value of commonly used severity-of-illness scores.
This study is a prospective observation and characterization of consecutive, mechanically ventilated patients in 3 internal medicine wards of a single hospital who were denied ICU admission. Outcome measures are as follows: 28-day mortality, survival to hospital discharge, and 3 months postdischarge.
Eighty-six patients were examined. The patients were 78.9 ± 8.9 years old; 53% were independent preadmission. Respiratory insufficiency due to infection was the main reason for mechanical ventilation (58%). Charlson and acute physiology scores (APS) averaged 4 ± 2.2 and 91.8 ± 26.7, respectively. Twenty-eight-day mortality was 71%, whereas in-hospital mortality was 74% and 3 months postdischarge mortality was 79%. Survivors were significantly younger than nonsurvivors (74.4 ± 8.5 years vs 80.4 ± 8.6 years, P < .01), were more likely to be ventilated for cardiac causes (41% vs 11%, P = .04), and had significantly higher initial mean blood pressure (79.4 mm Hg vs 58.2 mm Hg, P = .02) and blood albumin levels (29.8 g/L vs 25.7 g/L, P = .05). Death rate was 10 times more likely, with an APS greater than 90 on the day of intubation as compared with an APS less than 90.
Mortality in patients ventilated on the ward was high, especially in the subgroup of patients with an APS score greater than 90. The early calculation of APS may assist in focusing therapeutic efforts on patients with better survival chances.
Short-term prognosis of critically ill surgical patients: The impact of duration of invasive organ support therapies
2012, Journal of Critical Care
Citation Excerpt :
Thus, duration of renal replacement therapy was found to vary directly [16] or indirectly [17] with mortality or was without relevance for survival [8,18-21]. Correspondingly, some authors identified prolonged invasive ventilation as a determinant of short-term mortality [8,22,23], whereas others were unable to do so [7,19,20,24,25]. All previous studies (including our own) that addressed the issue of a prolonged invasive organ support used conventional hazard or logistic regression analyses to identify prognostic variables.
We wanted to identify the importance of the duration of invasive ventilation and of renal replacement therapy for short-term prognosis of surgical patients treated in an intensive care unit (ICU).
We analyzed adult patients (n = 1462) who had an ICU length of stay of more than 4 days and who were followed up until the end of the short-term phase after ICU admission. Duration of different invasive therapies was evaluated by constructing specific vectors that tested effects of time-dependent variables on outcome after a lag time of 7 days.
Eight hundred eight patients (56.6%) were still alive at the end of the short-term phase. During the short-term phase, 85.3% of the 1462 patients required invasive ventilation, and 16.1%, a continuous renal replacement therapy. Besides the underlying disease and disease severity at ICU admission, the need for invasive ventilation or renal replacement therapy was associated with poorer outcome. Duration of invasive ventilation shortened survival if treatment lasted for more than 11 days (nonlinear association). In contrast, duration of renal replacement therapy was unimportant for short-term prognosis.
Prolonged duration of invasive ventilation but not of renal replacement therapy is inversely related to short-term survival.
Physical training is beneficial to functional status and survival in patients with prolonged mechanical ventilation
2011, Journal of the Formosan Medical Association
Early physical training is necessary for severely deconditioned patients undergoing prolonged mechanical ventilation (PMV), because survivors often experience prolonged recovery. Long-term outcomes after physical training have not been measured; therefore, we investigated outcome during a 1-year period after physical training for the PMV patients.
We conducted a prospective randomized control trial in a respiratory care center. Thirty-four patients were randomly assigned to the rehabilitation group (n = 18) and the control group (n = 16). The rehabilitation group participated in supervised physical therapy training for 6 weeks, and continued in an unsupervised maintenance program for 6 more weeks. The functional independence measurement (FIM) was used to assess functional status. Survival status during the year after enrollment, the number of survivors discharged, and the number free from ventilator support were collected. These outcome parameters were assessed at entry, immediately after the 6 weeks physical therapy training period, after 6 weeks unsupervised maintenance exercise program, and 6 months and 12 months after study entry.
The scores of total FIM, motor domain, cognitive domain, and some sub-items, except for the walking/wheelchair sub-item, increased significantly in the rehabilitation group at 6 months postenrollment, but remained unchanged for the control group. The eating, comprehension, expression, and social interaction subscales reached the 7-point complete independence level at 6 months in the rehabilitation group, but not in the control group. The 1-year survival rate for the rehabilitation group was 70%, which was significantly higher than that for the control group (25%), although the proportion of patients discharged and who were ventilator-free in the rehabilitation and control groups did not differ significantly.
Six weeks physical therapy training plus 6 weeks unsupervised maintenance exercise enhanced functional levels and increased survival for the PMV patients compared with those with no such intervention. Early physical therapy interventions are needed for the PMV patients in respiratory care centers. [J Formos Med Assoc 2011; 110(X):XX–XX]
Patient-specific, time-varying predictors of post-ICU informal caregiver burden: The caregiver outcomes after ICU discharge project
2010, Chest
The outcomes of informal caregivers of survivors of critical illness likely depend on patient characteristics, which may change over time. To date, few studies have examined patient-specific predictors of post-ICU informal caregiver burden, and none has tested whether predictors vary after hospital discharge.
We designed a prospective, longitudinal observational study, enrolling 48 patient-caregiver dyads from four ICUs in a university hospital. Informal caregiver depression symptoms were measured with the Center for Epidemiologic Studies Depression scale. Lifestyle disruption was measured with the Activity Restriction Scale. Linear regression models were built to test for patient- and caregiver-specific predictors of depression symptoms and lifestyle disruption 2, 6, and 12 months after ICU admission.
Patients had a mean (SD) age of 52.5 (19.7) years, 67% were men, median (interquartile range) Acute Physiology and Chronic Health Evaluation score was 52 (38.5, 65). The caregivers had a mean (SD) age of 52.8 (12.8) years, 91.2% were women, and 48% were spouses. Predictors of caregiver depression symptoms were patient gender (men) at 2 and 12 months and tracheostomy at 12 months. Predictors of lifestyle disruption were patient education (more common among high school graduates) and patient gender (men) at 2 months, and tracheostomy, functional dependency, and patient gender (men) at 12 months.
The determinants of post-ICU informal caregiver burden likely depend on characteristics of the patient as well as the caregiver and may vary over time. Further research is necessary to better understand the longitudinal determinants of burden in order to develop more effective caregiver interventions.

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: Supported by National Institute On Aging grant No. RO1AG11979.

^†: A list of study investigators is given in the Appendix.

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Chest

Clinical Investigations in Critical Care2-Month Mortality and Functional Status of Critically Ill Adult Patients Receiving Prolonged Mechanical Ventilation

Study objectives

Design

Setting

Patients

Interventions

Measurements and results

Conclusions

Section snippets

Study Site and Patient Selection

Study Sample and Baseline Characteristics

Mortality

Conclusion

Appendix

Chest

Chest

Chest

J Chronic Dis

Chest

Chest

Older American 2000: key indicators of well-being. Federal Interagency Forum on Aging-Related Statistics

How is mechanical ventilation employed in the intensive care unit? An international utilization review

Am J Respir Crit Care Med

The graying of the intensive care unit: demographic changes 1988–98 [abstract]

Crit Care Med

Economics of prolonged mechanical ventilation

Am Rev Respir Dis

Mechanical ventilation in a cohort of elderly patients admitted to an intensive care unit

Ann Intern Med

Mechanical ventilation for the elderly patient in Intensive care: incremental charges and benefits

JAMA

Respiratory failure in the elderly: analysis of outcome after treatment with mechanical ventilation

Arch Intern Med

Intensive care for critically ill elderly: mortality, costs and quality of life

Arch Intern Med

Long-term outcome of critically ill elderly patients requiring intensive care

JAMA

Studies of illness in the aged: the index of ADL; a standardized measure of biological and psychosocial function

JAMA

Assessment of older people: self-maintaining and instrumental activities of daily living

Gerontologist

SF 36 health survey

The Center for Epidemiological Studies depression scale: a self-report depression scale for research in the general population

Appl Psychol Meas

Clinical Investigations in Critical Care
2-Month Mortality and Functional Status of Critically Ill Adult Patients Receiving Prolonged Mechanical Ventilation