Management of patients requiring prolonged mechanical ventilation: report of a NAMDRC consensus conference

Thirty years of home mechanical ventilation in children: escalating need for pediatric intensive care beds

Purpose

To describe trends in pediatric home mechanical ventilation (HMV) and their impact on the use of pediatric intensive care unit (PICU) beds.

Methods

Review of all children who had started HMV in a single center for HMV.

Results

Between 1979 and 2009, HMV was started in 197 patients [100 (51 %) with invasive and 97 with noninvasive ventilation], with a median age of 14.7 (range 0.5–17.9) years. Most patients (77 %) were males with a neuromuscular disorder (66 %). The number of children receiving HMV increased from 8 in the 1979–1988 period to 122 in the 1999–2008 period. This increase occurred foremost in patients aged 0–5 years and was accompanied by a sharp rise in the use of PICU beds. In 150 patients (76 %), HMV was initiated on an ICU with a total of 12,440 admission days, of which 10,385 days (83 %) could be attributed to 67 patients who started non-electively with invasive HMV. Of the latter, 52 patients had been admitted to a PICU with a total of 9,335 admission days. At the end of the study, 134 patients (68 %) were still being ventilated, 43 patients (22 %) had died, 11 patients (6 %) were weaned from HMV, 4 patients (2 %) did not want to continue HMV and 5 patients (3 %) were lost to follow-up.

Conclusions

Over time, there was an impressive increase in the application of HMV in children. This increase was most obvious in the youngest age group with invasive HMV, and these children had very long stays in the PICU.

Mechanical ventilation in the emergency department for 24 hours or longer is associated with delayed weaning

PURPOSE

We examined various aspects of critical care to identify factors in the emergency department (ED) that affected the overall duration of mechanical ventilation (MV). We specifically focused on whether 24 hours of ED MV affected the weaning success and the duration of MV.

MATERIALS AND METHODS

Mechanical ventilation cases that started in the ED because of purely respiratory problems were enrolled in the retrospective cohort. We recorded demographic data, duration of MV in ED, various severity scores, previously known factors of prolonged MV, and achievement of ventilator weaning. All the significant factors in univariate survival analyses were included in a multivariate analysis.

RESULTS

The estimated median of the entire duration of MV was longer in patients who received 24 hours or more of MV in ED compared with that of patients who received MV for less than 24 hours (33.0 vs 15.4 days, P = .003). Mechanical ventilation for longer than 24 hours in the ED remained a significant factor that prolonged the entire MV duration in the multivariate analysis (hazard ratio, 0.577; P = .019). Hypoalbuminemia and abbreviated mortality in ED sepsis (MEDS) score were also independently correlated (P ≤ .001 for both).

CONCLUSIONS

Mechanical ventilation in the ED for 24 hours or longer is associated with delayed ventilator weaning.

Medical device-associated infections in the long-term care setting

Indwelling medical devices are increasingly used in long-term care facilities (LTCFs). These devices place residents at a heightened risk for infection and colonization and infection with multidrug-resistant organisms. Understanding the risk and pathogenesis of infection associated with commonly used medical devices can help facilitate appropriate therapy. Programs to minimize unnecessary use of indwelling medical devices in residents and maximize staff adherence to infection control and maintenance procedures are essential features of a LTCF infection prevention program. LTCFs that provide care for large numbers of residents with indwelling medical devices should routinely perform surveillance for device-related infections and develop systems for assessing the safety and efficacy of newly introduced device-related technology.

Economics of mechanical ventilation and respiratory failure

For patients with acute respiratory failure, mechanical ventilation provides the most definitive life-sustaining therapy. Because of the intense resources required to care for these patients, its use accounts for considerable costs. There is great societal need to ensure that use of mechanical ventilation maximizes societal benefits while minimizing costs, and that mechanical ventilation, and ventilator support in general, is delivered in the most efficient and cost-effective manner. This review summarizes the economic aspects of mechanical ventilation and summarizes the existing literature that examines its economic impact cost effectiveness.

Predictors of successful decannulation using a tracheostomy retainer in patients with prolonged weaning and persisting respiratory failure

BACKGROUND

For percutaneously tracheostomized patients with prolonged weaning and persisting respiratory failure, the adequate time point for safe decannulation and switch to noninvasive ventilation is an important clinical issue.

OBJECTIVES

We aimed to evaluate the usefulness of a tracheostomy retainer (TR) and the predictors of successful decannulation.

METHODS

We studied 166 of 384 patients with prolonged weaning in whom a TR was inserted into a tracheostoma. Patients were analyzed with regard to successful decannulation and characterized by blood gas values, the duration of previous spontaneous breathing, Simplified Acute Physiology Score (SAPS) and laboratory parameters.

RESULTS

In 47 patients (28.3%) recannulation was necessary, mostly due to respiratory decompensation and aspiration. Overall, 80.6% of the patients could be liberated from a tracheostomy with the help of a TR. The need for recannulation was associated with a shorter duration of spontaneous breathing within the last 24/48 h (p < 0.01 each), lower arterial oxygen tension (p = 0.025), greater age (p = 0.025), and a higher creatinine level (p = 0.003) and SAPS (p < 0.001). The risk for recannulation was 9.5% when patients breathed spontaneously for 19-24 h within the 24 h prior to decannulation, but 75.0% when patients breathed for only 0-6 h without ventilatory support (p < 0.001). According to ROC analysis, the SAPS best predicted successful decannulation [AUC 0.725 (95% CI: 0.634-0.815), p < 0.001]. Recannulated patients had longer durations of intubation (p = 0.046), tracheostomy (p = 0.003) and hospital stay (p < 0.001).

CONCLUSION

In percutaneously tracheostomized patients with prolonged weaning, the use of a TR seems to facilitate and improve the weaning process considerably. The duration of spontaneous breathing prior to decannulation, age and oxygenation describe the risk for recannulation in these patients.

The role of non-invasive home mechanical ventilation in patients with chronic obstructive pulmonary disease requiring prolonged weaning

BACKGROUND AND OBJECTIVE

Patients with COPD who require prolonged weaning from invasive mechanical ventilation show poor long-term survival. Whether non-invasive home mechanical ventilation (HMV) has a beneficial effect after prolonged weaning has not yet been clearly determined.

METHODS

Patients with COPD who required prolonged weaning and were admitted to a specialized weaning centre between January 2002 and February 2008 were enrolled in the study. Long-term survival and prognostic factors, including the role of non-invasive HMV, were evaluated.

RESULTS

Of 117 patients (87 men, 30 women; mean age 69.5±9.5 years) included in the study, weaning from invasive ventilation was achieved in 82 patients (70.1%). Successful weaning was associated with better survival 1 year after discharge from hospital (hazard ratio (HR) 2.24, 95% CI: 1.16-4.31; P=0.016). Among the 82 patients who were successfully weaned, non-invasive HMV was initiated in 39 (47.6%) due to persistent chronic ventilatory failure. Initiation of HMV was associated with a higher rate of survival to 1 year as compared with patients who did not receive ventilatory support (84.2% vs 54.3%; HR 3.68, 95% CI: 1.43-9.43; P=0.007). In addition, younger age and higher PaO₂, haemoglobin concentration and haematocrit at discharge were associated with better survival. In an adjusted multivariate analysis, initiation of non-invasive HMV after successful weaning remained an independent prognostic factor for survival to 1 year (HR 3.63, 95% CI: 1.23-10.75; P=0.019).

CONCLUSIONS

These findings suggest that based on the potential for improvement in long-term survival, non-invasive HMV should be considered in patients with severe COPD and persistent chronic hypercapnic respiratory failure after prolonged weaning.

Long-term survival in patients with tracheostomy and prolonged mechanical ventilation in Olmsted County, Minnesota

BACKGROUND

An increasing number of patients require prolonged mechanical ventilation (PMV), which is associated with high morbidity and poor long-term survival, but there are few data regarding the incidence and outcome of PMV patients from a community perspective.

METHODS

We retrospectively reviewed the electronic medical records of adult Olmsted county, Minnesota, residents admitted to the intensive care units at the 2 Mayo Clinic Rochester hospitals from January 1, 2003, to December 31, 2007, who underwent tracheostomy for PMV.

RESULTS

Sixty-five patients, median age 68 years (interquartile range [IQR] 49-80 y), 39 male, underwent tracheostomy for PMV, resulting in an age-adjusted incidence of 13 (95% CI 10-17) per 100,000 patient-years at risk. The median number of days on mechanical ventilation was 24 days (IQR 18-37 d). Forty-six patients (71%) survived to hospital discharge, and 36 (55%) were alive at 1-year follow-up. After adjusting for age and baseline severity of illness, the presence of COPD was independently associated with 1-year mortality (hazard ratio 3.4, 95% CI 1.4-8.2%).

CONCLUSIONS

There was a considerable incidence of tracheostomy for PMV. The presence of COPD was an independent predictor of 1-year mortality.

Characterization of pediatric patients receiving prolonged mechanical ventilation

OBJECTIVE

To describe the characteristics and risk factors of pediatric patients who receive prolonged mechanical ventilation, defined as ventilatory support for >21 days.

DESIGN

Prospective cohort.

SETTING

Four medical-surgical pediatric intensive care units in four university-affiliated hospitals in Argentina.

PATIENTS

All consecutive patients from 1 month to 15 yrs old admitted to participating pediatric intensive care units from June 1, 2007, to August 31, 2007, who received mechanical ventilation (invasive or noninvasive) for >12 hrs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographic and physiologic data on admission to the pediatric intensive care units, drugs and events during the study period, and outcomes were prospectively recorded. A total of 256 patients were included. Of these, 23 (9%) required mechanical ventilation for >21 days and were assigned to the prolonged mechanical ventilation group. Patients requiring prolonged mechanical ventilation had higher mortality (43% vs. 21%, p < .05) and longer pediatric intensive care unit stay: 35 days [28-64 days] vs. 10 days [6-14]). There was no difference between the groups in age and gender distribution, reasons for admission, incidence of immunodeficiencies, or Paediatric Index of Mortality 2 score. The only difference at admission was a higher rate of genetic diseases in prolonged mechanical ventilation patients (26% vs. 9%, p < .05). There was a higher incidence of septic shock (87% vs. 34%, p < .01), acute respiratory distress syndrome (43% vs. 20%, p < .01), and ventilator-associated pneumonia (35% vs. 8%, p < .01) and higher utilization of dopamine (78% vs. 42%, p < .01), norepinephrine (61% vs. 15%, p < .01), multiple antibiotics (83% vs. 20%, p < .01), and blood transfusions (52% vs. 14%, p < .01). The proportion of extubation failure was higher in the prolonged mechanical ventilation group with similar rates of unplanned extubations in both groups. Variables remaining significantly associated with prolonged mechanical ventilation after multivariate analysis were treatment with multiple antibiotics, septic shock, ventilator-associated pneumonia, and use of norepinephrine.

CONCLUSIONS

Patients with prolonged mechanical ventilation have more complications and require more pediatric intensive care unit resources. Mortality in these patients duplicates that from those requiring shorter support.

Physical training is beneficial to functional status and survival in patients with prolonged mechanical ventilation

BACKGROUND/PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Skeletal morbidity among survivors of critical illness

OBJECTIVES

To describe the incident fracture rate in survivors of critical illness and to compare fracture risk with population-matched control subjects.

DESIGN

Retrospective longitudinal case-cohort study.

SETTING

A tertiary adult intensive care unit in Australia.

PATIENTS

All patients ventilated admitted to intensive care and requiring mechanical ventilation for ≥48 hrs between January 1998 and December 2005.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

New fractures were identified in the study population for the postintensive care unit period (intensive care unit discharge to January 2008). The incident fracture rate and age-adjusted fracture risk of the female intensive care unit population were compared with the general population adult females derived from the Geelong Osteoporosis Study. Over the 8-yr period, a total of 739 patients (258 women, 481 men) were identified. After a median follow-up of 3.7 yrs (interquartile range, 2.0-5.9 yrs) for women and 4.0 yrs (interquartile range, 2.1-6.1 yrs) for men, incident fracture rates (95% confidence interval) per 100 patient years were 3.84 (2.58-5.09) for females 2.41 (1.73-3.09) for males. Compared with an age-matched random population-based sample of women, elderly women were at increased risk for sustaining an osteoporosis-related fracture after critical illness (hazard ratio, 1.65; 95% confidence interval, 1.08-2.52; p = .02).

CONCLUSIONS

The increase in fracture risk observed in postintensive care unit older females suggests an association between critical illness and subsequent skeletal morbidity. The explanation for this association is not explored in this study and includes the effects of pre-existing patient factors and/or direct effects of critical illness. Prospective research evaluating risk factors, the relationship between critical illness and bone turnover, the extent and duration of bone loss, and the associated morbidity in this population is warranted.

Nutrition management for the patient requiring prolonged mechanical ventilation

Patients requiring prolonged mechanical ventilation are often medically complex and present with a wide range of pulmonary conditions, including neuromuscular diseases, chronic pulmonary diseases, and chronic critical illness. These patients present the nutrition support professional with many challenges. However, accurate nutrition assessment, timely and effective nutrition interventions, and careful monitoring will help patients meet their medical and nutrition goals.

Renal replacement therapy in prolonged mechanical ventilation patients with renal failure in Taiwan

BACKGROUND

Renal failure requiring renal replacement therapy (RRT) is associated with a high mortality rate in intensive care unit (ICU) patients. Little information is available on the outcomes of patients having prolonged mechanical ventilation (PMV) in addition to RRT. The purpose of this study was to investigate the impact of RRT in PMV patients.

METHODS

This was an observational, retrospective study in the 24-bed respiratory care center (RCC) of Chang Gung Memorial Hospital, Taiwan, between May 2001 and April 2007. The end points were weaning rate and survival rate at the RCC.

RESULTS

Of the 1301 RCC patients, 157 patients (13.7%) underwent RRT. The RRT patients had lower successful weaning rate (39.5% vs 58.4%, P < .001) and RCC survival rate (45.9% vs 71.9%, P < .001) compared with without-RRT patients. The successful weaning rates of end-stage renal disease (ESRD) patients, patients with RRT initiated at the ICU and continued at RCC, and patients whose RRT was initiated at the RCC were 49.2%, 39.1%, and 22.2%, respectively. The RCC survival rates were 50.8%, 47.8%, and 29.6%, respectively. The odds ratios of successful weaning rate and survival rate were 0.295 (95% confidence interval, 0.105-0.833; P = .021) and 0.407 (95% confidence interval, 0.155-1.021; P = .069) for patients whose RRT was initiated at the RCC vs ESRD patients.

CONCLUSION

The present study demonstrates that the need for RRT had a negative impact on weaning and mortality in PMV patients compared with patients without RRT. Patients who had RRT initiated at the RCC had a significantly lower weaning rate compared with ESRD patients.

Predictors of prolonged weaning and survival during ventilator weaning in a respiratory ICU

PURPOSE

An International Consensus Conference proposed classifying weaning into simple, difficult, and prolonged weaning. However, the usefulness of this classification in a respiratory intensive care unit (ICU) is unknown. The aims of the study were: (1) to compare the clinical characteristics and outcomes of patients from the three weaning groups in a respiratory ICU; and (2) to assess predictors for prolonged weaning and survival.

METHODS

We prospectively studied 181 mechanically ventilated patients (131, 72% with chronic respiratory disorders) in whom weaning had been initiated, divided into simple (78, 43%), difficult (70, 39%), and prolonged (33, 18%) weaning. We compared the characteristics and outcomes among the three groups and determined the factors associated with prolonged weaning and survival in multivariate analysis.

RESULTS

Patients with simple and difficult weaning had similar characteristics and outcomes. A higher proportion of patients with prolonged weaning had chronic obstructive pulmonary disease, and these patients also had more complications, a longer stay and lower survival. Increased heart rate (≥105 min(-1), p < 0.001) and PaCO(2) (≥ 54 mmHg, p = 0.001) during the spontaneous breathing trial independently predicted prolonged weaning. In addition, the need for reintubation (p < 0.001) and hypercapnia during the spontaneous breathing trial (p = 0.003) independently predicted a decreased 90-day survival.

CONCLUSION

Because of the similar characteristics and outcomes, the differentiation between simple and difficult weaning had no relevant clinical consequences in a respiratory ICU. Patients with prolonged weaning had the worst outcomes. For the overall population, hypercapnia at the end of spontaneous breathing predicts prolonged weaning and a worse survival, and clinicians should implement measures aimed at improving weaning outcome.

Prolonged mechanical ventilation in critically ill patients: epidemiology, outcomes and modelling the potential cost consequences of establishing a regional weaning unit

INTRODUCTION

The number of patients requiring prolonged mechanical ventilation (PMV) is likely to increase. Transferring patients to specialised weaning units may improve outcomes and reduce costs. The aim of this study was to establish the incidence and outcomes of PMV in a UK administrative health care region without a dedicated weaning unit, and model the potential impact of establishing a dedicated weaning unit.

METHODS

A retrospective cohort study was undertaken using a database of admissions to three intensive care units (ICU) in a UK region from 2002 to 2006. Using a 21 day cut-off to define PMV, incidence was calculated using all ICU admissions and ventilated ICU admissions as denominators. Outcomes for the PMV cohort (mortality and hospital resource use) were compared with the non-PMV cohort. Length of ICU stay beyond 21 days was used to model the effect of establishing a weaning unit in terms of unit occupancy rates, admission refusal rates, and healthcare costs.

RESULTS

Out of 8290 ICU admission episodes, 7848 were included in the analysis. Mechanical ventilation was required during 5552 admission episodes, of which 349 required PMV. The incidence of PMV was 4.4 per 100 ICU admissions, and 6.3 per 100 ventilated ICU admissions. PMV patients used 29.1% of all general ICU bed days, spent longer in hospital after ICU discharge than non-PMV patients (median 17 vs 7 days, P < 0.001) and had higher hospital mortality (40.3% vs 33.8%, P = 0.02). For the region, in which about 70 PMV patients were treated each year, a weaning unit with a capacity of three beds appeared most cost efficient, resulting in an occupancy rate of 73%, admission refusal rate at 21 days of 36%, and potential cost saving of £344,000 (€418,000) using UK healthcare tariffs.

CONCLUSIONS

One in every sixteen ventilated patients requires PMV in our region and this group use a substantial amount of health care resource. Establishing a weaning unit would potentially reduce acute bed occupancy by 8-10% and could reduce overall treatment costs. Restructuring the current configuration of critical care services to introduce weaning units should be considered if the expected increase in PMV incidence occurs.

Estimation of quality-adjusted life expectancy in patients under prolonged mechanical ventilation

OBJECTIVES

The purpose of this study was to estimate the quality-adjusted life expectancy (QALE) and the expected lifetime utility loss of patients with prolonged mechanical ventilation (PMV).

METHODS

PMV was defined as more than 21 days of mechanical ventilation. A total of 633 patients fulfilled this definition and were followed for 9 years (1998-2007) to obtain their survival status. Quality of life of 142 patients was measured with the EuroQol five-dimensional (EQ-5D) questionnaire during the period 2008 to 2009. The survival probabilities for each time point were adjusted with a utility measurement of quality of life and then extrapolated to 300 months to obtain the QALE. We compared the age-, gender-matched reference populations to calculate the expected lifetime utility loss.

RESULTS

The average age of subjects was 76 years old. The life expectancy and loss of life expectancy were 1.95 years and 8.48 years, respectively. The QALE of 55 patients with partial cognitive ability and the ability to respond was 0.58 quality-adjusted life years (QALY), whereas the QALEs of 87 patients with poor consciousness were 0.28 and 0.29 QALY for the EQ-5D measured by family caregivers and nurses, respectively. The loss of QALE for PMV patients was 9.87 to 10.17 QALY, corresponding to a health gap of 94% to 97%.

CONCLUSIONS

Theses results of poor prognosis would provide stakeholders evidence for communication to facilitate clinical decisions. The estimation may be used in future studies to facilitate the cost-effectiveness and reduction of the health gap.

The difficult-to-wean patient

Up to 20% of patients requiring mechanical ventilation will suffer from difficult weaning (the need of more than 7 days of weaning after the first spontaneous breathing trial), which may depend on several reversible causes: respiratory and/or cardiac load, neuromuscular and neuropsychological factors, and metabolic and endocrine disorders. Clinical consequences (and/or often causes) of prolonged mechanical ventilation comprise features such as myopathy, neuropathy, and body composition alterations and depression, which increase the costs, morbidity and mortality of this. These difficult-to-wean patients may be managed in two type of units: respiratory intermediate-care units and specialized regional weaning centers. Two weaning protocols are normally used: progressive reduction of ventilator support (which we usually use), or progressively longer periods of spontaneous breathing trials. Physiotherapy is an important component of weaning protocols. Weaning success depends strongly on patients&#x2019; complexity and comorbidities, hospital organization and personnel expertise, availability of early physiotherapy, use of weaning protocols, patients&#x2019; autonomy and families&#x2019; preparation for home discharge with mechanical ventilation.

Chronic critical illness: prevalence, profile, and pathophysiology

The syndrome of chronic critical illness has well-documented emotional, social, and financial burdens for individuals, caregivers, and the health care system. The purpose of this article is to provide experienced acute and critical care clinicians with essential information about the prevalence and profile of the chronically critically ill patient needed for comprehensive care. In addition, pathophysiology contributing to chronic critical illness is addressed, though the exact mechanism underlying the conversion of acute critical illness to chronic critical illness is unknown. Clinicians can use this information to identify at-risk intensive care unit patients and to institute proactive care to minimize burden and distress experienced by patients and their caregivers.

Mortality and readmission among ventilator-dependent patients after successful weaned discharge from a respiratory care ward

BACKGROUND/PURPOSE

Patients on prolonged mechanical ventilation in Taiwan are stepped down to a respiratory care ward (RCW) for further respiratory care. Only a few patients in the RCW can ultimately be weaned and discharged. In this study, we tried to determine factors that predict mortality and readmission of these patients in the post-discharge period.

METHODS

Between May 1, 2004 and October 31, 2006, clinical data were retrospectively analyzed for eligible patients in a RCW. Patients who were successfully weaned from mechanical ventilation were enrolled in this study.

RESULTS

A total of 243 patients were eligible for evaluation, and 67 patients were successfully weaned and discharged. By Kaplan-Meier curve, 36 (67.1%) patients were readmitted within 3 months after discharge, and among these, 23 (63.9%) had mechanical ventilation reinstituted at the time of first readmission. The most common cause of readmission was airway infection (80.5%). Overall mortality and readmission rates at 1 year after weaned discharge were 32.9% and 88.2%, respectively. By multivariate analysis, patients with neurologic causes of ventilator dependency were less likely to be readmitted (hazard ratio = 0.36; p =0.034), and neoplastic diseases (hazard ratio = 4.66; p =0.031) were independently associated with mortality.

CONCLUSION

Underlying comorbidities and causes of ventilator dependency are important predictors of mortality and readmission among patients after weaned discharge from a RCW.

Chronic critical illness

Although advances in intensive care have enabled more patients to survive an acute critical illness, they also have created a large and growing population of chronically critically ill patients with prolonged dependence on mechanical ventilation and other intensive care therapies. Chronic critical illness is a devastating condition: mortality exceeds that for most malignancies, and functional dependence persists for most survivors. Costs of treating the chronically critically ill in the United States already exceed $20 billion and are increasing. In this article, we describe the constellation of clinical features that characterize chronic critical illness. We discuss the outcomes of this condition including ventilator liberation, mortality, and physical and cognitive function, noting that comparisons among cohorts are complicated by variation in defining criteria and care settings. We also address burdens for families of the chronically critically ill and the difficulties they face in decision-making about continuation of intensive therapies. Epidemiology and resource utilization issues are reviewed to highlight the impact of chronic critical illness on our health care system. Finally, we summarize the best available evidence for managing chronic critical illness, including ventilator weaning, nutritional support, rehabilitation, and palliative care, and emphasize the importance of efforts to prevent the transition from acute to chronic critical illness. As steps forward for the field, we suggest a specific definition of chronic critical illness, advocate for the creation of a research network encompassing a broad range of venues for care, and highlight areas for future study of the comparative effectiveness of different treatment venues and approaches.

One-year trajectories of care and resource utilization for recipients of prolonged mechanical ventilation: a cohort study

BACKGROUND

Growing numbers of critically ill patients receive prolonged mechanical ventilation. Little is known about the patterns of care as patients transition from acute care hospitals to postacute care facilities or about the associated resource utilization.

OBJECTIVE

To describe 1-year trajectories of care and resource utilization for patients receiving prolonged mechanical ventilation.

DESIGN

1-year prospective cohort study.

SETTING

5 intensive care units at Duke University Medical Center, Durham, North Carolina.

PARTICIPANTS

126 patients receiving prolonged mechanical ventilation (defined as ventilation for >or=4 days with tracheostomy placement or ventilation for >or=21 days without tracheostomy), as well as their 126 surrogates and 54 intensive care unit physicians, enrolled consecutively over 1 year.

MEASUREMENTS

Patients and surrogates were interviewed in the hospital, as well as 3 and 12 months after discharge, to determine patient survival, functional status, and facility type and duration of postdischarge care. Physicians were interviewed in the hospital to elicit prognoses. Institutional billing records were used to assign costs for acute care, outpatient care, and interfacility transportation. Medicare claims data were used to assign costs for postacute care.

RESULTS

103 (82%) hospital survivors had 457 separate transitions in postdischarge care location (median, 4 transitions [interquartile range, 3 to 5 transitions]), including 68 patients (67%) who were readmitted at least once. Patients spent an average of 74% (95% CI, 68% to 80%) of all days alive in a hospital or postacute care facility or receiving home health care. At 1 year, 11 patients (9%) had a good outcome (alive with no functional dependency), 33 (26%) had a fair outcome (alive with moderate dependency), and 82 (65%) had a poor outcome (either alive with complete functional dependency [4 patients; 21%] or dead [56 patients; 44%]). Patients with poor outcomes were older, had more comorbid conditions, and were more frequently discharged to a postacute care facility than patients with either fair or good outcomes (P < 0.05 for all). The mean cost per patient was $306,135 (SD, $285,467), and total cohort cost was $38.1 million, for an estimated $3.5 million per independently functioning survivor at 1 year.

LIMITATION

The results of this single-center study may not be applicable to other centers.

CONCLUSION

Patients receiving prolonged mechanical ventilation have multiple transitions of care, resulting in substantial health care costs and persistent, profound disability. The optimism of surrogate decision makers should be balanced by discussions of these outcomes when considering a course of prolonged life support.

PRIMARY FUNDING SOURCE

None.

A proposal of a new model for long-term weaning: respiratory intensive care unit and weaning center

BACKGROUND

Respiratory intermediate care units (RICU) are hospital locations to treat acute and acute on chronic respiratory failure. Dedicated weaning centers (WC) are facilities for long-term weaning.

AIM

We propose and describe the initial results of a long-term weaning model consisting of sequential activity of a RICU and a WC.

METHODS

We retrospectively analysed characteristics and outcome of tracheostomised difficult-to wean patients admitted to a RICU and, when necessary, to a dedicated WC along a 18-month period.

RESULTS

Since February 2008 to November 2009, 49 tracheostomised difficult-to wean patients were transferred from ICUs to a University-Hospital RICU after a mean ICU length of stay (LOS) of 32.6 +/- 26.6 days. The weaning success rate in RICU was 67.3% with a mean LOS of 16.6 +/- 10.9 days. Five patients (10.2%) died either in the RICU or after being transferred to ICU, 10 (20.4%) failed weaning and were transferred to a dedicated WC where 6 of them (60%) were weaned. One of these patients was discharged from WC needing invasive mechanical ventilation for less than 12h, 2 died in the WC, 1 was transferred to a ICU. The overall weaning success rate of the model was 79.6%, with 16.3% and 4.8% in-hospital and 3-month mortality respectively. The model resulted in an overall 39 845 +/- 22 578 euro mean cost saving per patient compared to ICU.

CONCLUSION

The sequential activity of a RICU and a WC resulted in additive weaning success rate of difficult-to wean patients. The cost-benefit ratio of the program warrants prospective investigations.

Long-term acute care hospital utilization after critical illness

CONTEXT

Long-term acute care hospitals have emerged as a novel approach for the care of patients recovering from severe acute illness, but the extent and increases in their activity at the national level are unknown.

OBJECTIVE

To examine temporal trends in long-term acute care hospital utilization after an episode of critical illness among fee-for-service Medicare beneficiaries aged 65 years or older.

DESIGN, SETTING, AND PATIENTS

Retrospective cohort study using the Medicare Provider Analysis and Review files from 1997 to 2006. We included all Medicare hospitalizations involving admission to an intensive care unit of an acute care, nonfederal hospital within the continental United States.

MAIN OUTCOME MEASURES

Overall long-term acute care utilization, associated costs, and survival following transfer.

RESULTS

The number of long-term acute care hospitals in the United States increased at a mean rate of 8.8% per year, from 192 in 1997 to 408 in 2006. During that time, the annual number of long-term acute care admissions after critical illness increased from 13,732 to 40,353, with annual costs increasing from $484 million to $1.325 billion. The age-standardized population incidence of long-term acute care utilization after critical illness increased from 38.1 per 100,000 in 1997 to 99.7 per 100,000 in 2006, with greater use among male individuals and black individuals in all periods. Over time, transferred patients had higher numbers of comorbidities (5.0 in 1997-2000 vs 5.8 in 2004-2006, P < .001) and were more likely to receive mechanical ventilation at the long-term acute care hospital (16.4% in 1997-2000 vs 29.8% in 2004-2006, P < .001). One-year mortality after long-term acute care hospital admission was high throughout the study period: 50.7% in 1997-2000 and 52.2% in 2004-2006.

CONCLUSIONS

Long-term acute care hospital utilization after critical illness is common and increasing. Survival among Medicare beneficiaries transferred to long-term acute care after critical illness is poor.

Ventilator-associated pneumonia in long-term ventilator-assisted individuals

BACKGROUND

Information on the characteristics of pneumonia in long-term ventilator-assisted individuals is scarce. We evaluate the incidence, risk factors and outcome of ventilator-associated pneumonia (VAP) in a large series of chronically ventilated patients.

METHODS

All patients assisted in a chronic ventilator-dependent unit were prospectively followed up for the development of VAP. Patients with a new and persistent lung infiltrate and a purulent tracheal aspirate were suspected to have VAP. Pneumonia was considered microbiologically confirmed in the presence of (1) a positive blood culture and/or (2) ≥10⁵ CFU ml⁻¹ in quantitative bacterial culture of tracheal aspirates or ≥10³ CFU ml⁻¹ in quantitative mini-bronchoalveolar lavage cultures.

RESULTS

In total, 100 consecutive long-term ventilated individuals with spinal cord injury (mean age 49 years) were prospectively followed up. The length of mechanical ventilation before admission in the unit was 54±37 days, and the follow-up after admission was 119±127 days. There were 32 episodes of VAP in 27 patients (1.74 episodes per 1000 days of mechanical ventilation). By logistic regression analysis, hypoalbuminaemia (P=0.03), administration of antacids (P=0.002) and length of mechanical ventilation (P=0.05) were independent risk factors for VAP. The most frequently isolated organisms were Pseudomonas aeruginosa (62%), methicillin-resistant Staphylococcus aureus (25%) and Acinetobacter baumannii (15%); 9 (28%) episodes were polymicrobial. Antimicrobial treatment, including monotherapy in 66%, was successful in most patients. Only three patients (11%) died in relation to VAP.

CONCLUSIONS

Patients on long-term ventilation are at significant risk for the development of VAP, but the mortality is low.

Sepsis-induced myopathy

Sepsis is a major cause of morbidity and mortality in critically ill patients, and despite advances in management, mortality remains high. In survivors, sepsis increases the risk for the development of persistent acquired weakness syndromes affecting both the respiratory muscles and the limb muscles. This acquired weakness results in prolonged duration of mechanical ventilation, difficulty weaning, functional impairment, exercise limitation, and poor health-related quality of life. Abundant evidence indicates that sepsis induces a myopathy characterized by reductions in muscle force-generating capacity, atrophy (loss of muscle mass), and altered bioenergetics. Sepsis elicits derangements at multiple subcellular sites involved in excitation contraction coupling, such as decreasing membrane excitability, injuring sarcolemmal membranes, altering calcium homeostasis due to effects on the sarcoplasmic reticulum, and disrupting contractile protein interactions. Muscle wasting occurs later and results from increased proteolytic degradation as well as decreased protein synthesis. In addition, sepsis produces marked abnormalities in muscle mitochondrial functional capacity and when severe, these alterations correlate with increased death. The mechanisms leading to sepsis-induced changes in skeletal muscle are linked to excessive localized elaboration of proinflammatory cytokines, marked increases in free-radical generation, and activation of proteolytic pathways that are upstream of the proteasome including caspase and calpain. Emerging data suggest that targeted inhibition of these pathways may alter the evolution and progression of sepsis-induced myopathy and potentially reduce the occurrence of sepsis-mediated acquired weakness syndromes.

Expectations and outcomes of prolonged mechanical ventilation

OBJECTIVE

To compare prolonged mechanical ventilation decision-makers' expectations for long-term patient outcomes with prospectively observed outcomes and to characterize important elements of the surrogate-physician interaction surrounding prolonged mechanical ventilation provision. Prolonged mechanical ventilation provision is increasing markedly despite poor patient outcomes. Misunderstanding prognosis in the prolonged mechanical ventilation decision-making process could provide an explanation for this phenomenon.

DESIGN

Prospective observational cohort study.

SETTING

Academic medical center.

PATIENTS

A total of 126 patients receiving prolonged mechanical ventilation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Participants were interviewed at the time of tracheostomy placement about their expectations for 1-yr patient survival, functional status, and quality of life. These expectations were then compared with observed 1-yr outcomes measured with validated questionnaires. The 1-yr follow-up was 100%, with the exception of patient death or cognitive inability to complete interviews. At 1 yr, only 11 patients (9%) were alive and independent of major functional status limitations. Most surrogates reported high baseline expectations for 1-yr patient survival (n = 117, 93%), functional status (n = 90, 71%), and quality of life (n = 105, 83%). In contrast, fewer physicians described high expectations for survival (n = 54, 43%), functional status (n = 7, 6%), and quality of life (n = 5, 4%). Surrogate-physician pair concordance in expectations was poor (all kappa = <0.08), as was their accuracy in outcome prediction (range = 23%-44%). Just 33 surrogates (26%) reported that physicians discussed what to expect for patients' likely future survival, general health, and caregiving needs.

CONCLUSIONS

One-year patient outcomes for prolonged mechanical ventilation patients were significantly worse than expected by patients' surrogates and physicians. Lack of prognostication about outcomes, discordance between surrogates and physicians about potential outcomes, and surrogates' unreasonably optimistic expectations seem to be potentially modifiable deficiencies in surrogate-physician interactions.

Composite outcomes of chronically critically ill patients 4 months after hospital discharge

BACKGROUND

Data on likely postdischarge outcomes are important for decision making about chronically critically ill patients. It seems reasonable to categorize outcomes into "better" or overall desirable states and "worse" or generally undesirable states. Survival, being at home, and being cognitively intact are commonly identified as important to quality of life and thus may be combined to describe composite outcome states.

OBJECTIVE

To categorize postdischarge outcome states of chronically critically ill patients and identify predictors of better and worse states.

METHODS

Reanalysis of data from a trial of a disease management program for chronically critically ill patients. Two composite outcomes were created: (1) the "better" outcome: no cognitive impairment at 2 months after discharge and alive and at home at 4 months (ie, met all 3 criteria), and (2) the "worse" outcome: cognitive impairment 2 months after discharge, or death after discharge, or not living at home 4 months after discharge (ie, met at least 1 of these criteria).

RESULTS

Of 218 patients not requiring ventilatory support at discharge, 111 (50.9%) had a better outcome. Of 159 patients who were cognitively intact at discharge, 111 (69.8%) had a better outcome. Of the 39 patients who required ventilatory support at discharge, only 1 (3%) achieved the better outcome. Of 98 patients who were cognitively impaired at discharge, only 29 (30%) had the better outcome.

CONCLUSION

Need for mechanical ventilatory support and persistent cognitive impairment at discharge were associated with worse outcomes 4 months after discharge.

Acute respiratory failure in intensive care units. FINNALI: a prospective cohort study

OBJECTIVE

To evaluate the incidence, treatment and mortality of acute respiratory failure (ARF) in Finnish intensive care units (ICUs).

STUDY DESIGN

Prospective multicentre cohort study.

METHODS

All adult patients in 25 ICUs were screened for use of invasive or non-invasive ventilatory support during an 8-week period. Patients needing ventilatory support for more than 6 h were included and defined as ARF patients. Risk factors for ARF and details of prior chronic health status were assessed. Ventilatory and concomitant treatments were evaluated and recorded daily throughout the ICU stay. ICU and 90-day mortalities were assessed.

RESULTS

A total of 958 (39%) from the 2,473 admitted patients were treated with ventilatory support for more than 6 h. Incidence of ARF, acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) was 149.5, 10.6 and 5.0/100,000 per year, respectively. Ventilatory support was started with non-invasive interfaces in 183 of 958 (19%) patients. Ventilatory modes allowing triggering of spontaneous breaths were preferred (81%). Median tidal volume/predicted body weight was 8.7 (7.6-9.9) ml/kg and plateau pressure 19 (16-23) cmH2O. The 90-day mortality of ARF was 31%.

CONCLUSIONS

While the incidence of ARF requiring ventilatory support is higher, the incidence of ALI and ARDS seems to be lower in Finland than previously reported in other countries. Tidal volumes are higher than recommended in the concept of lung protective strategy. However, restriction of peak airway pressure was used in the majority of ARF patients.

Exploring the quality of dying of patients with chronic obstructive pulmonary disease in the intensive care unit: a mixed methods study

RATIONALE FOR THE STUDY

Improving the quality of end-of-life (EOL) care in critical care settings is a high priority. Patients with advanced chronic obstructive pulmonary disease (COPD) are frequently admitted to and die in critical care units. To date, there has been little research examining the quality of EOL care for this unique subpopulation of critical care patients.

AIMS

The aims of this study were (a) to examine critical care clinician perspectives on the quality of dying of patients with COPD and (b) to compare nurse ratings of the quality of dying and death between patients with COPD with those who died from other illnesses in critical care settings.

DESIGN AND SAMPLE

A sequential mixed method design was used. Three focus groups provided data describing the EOL care provided to patients with COPD dying in the intensive care unit (ICU). Nurses caring for patients who died in the ICU completed a previously validated, cross-sectional survey (Quality of Dying and Death) rating the quality of dying for 103 patients.

DATA ANALYSIS

Thematic analysis was used to analyse the focus group data. Total and item scores for 34 patients who had died in the ICU with COPD were compared with those for 69 patients who died from other causes.

RESULTS

Three primary themes emerged from the qualitative data are as follows: managing difficult symptoms, questioning the appropriateness of care and establishing care priorities. Ratings for the quality of dying were significantly lower for patients with COPD than for those who died from other causes on several survey items, including dyspnoea, anxiety and the belief that the patient had been kept alive too long. The qualitative data allowed for in-depth explication of the survey results.

CONCLUSIONS

Attention to the management of dyspnoea, anxiety and treatment decision-making are priority concerns when providing EOL care in the ICU to patients with COPD.

Contradictions in end-of-life decisions for self and other, expressed by relatives of chronically ventilated patients

OBJECTIVES

In certain populations, social, legal, and religious factors may influence end-of-life decisions in ventilator-dependent patients. This study aims to evaluate attitudes of first-degree relatives of chronically ventilated patients in Israel, toward end-of-life decisions regarding their loved ones, themselves, and unrelated others.

MATERIALS AND METHODS

The study was conducted in a chronic ventilation unit. First-degree family members of chronically ventilated patients were interviewed about their end-of-life attitudes for patients with end-stage diseases. Distinctions were made between attitudes in the case of their ventilated relatives, themselves, and unrelated others; between conscious and unconscious patients; and between a variety of interventions.

RESULTS

Thirty-one family members of 25 patients were interviewed. Median length of ventilation at the time of the interview was 13.4 months. Most interviewees wanted further interventions for their ventilated relatives, yet, for themselves, only 21% and 18% supported chronic ventilation and resuscitation, respectively, and 48% would want to be disconnected from the ventilator. Interventions were more likely to be endorsed for others (vs self), for the conscious self (vs unconscious self), and for artificial feeding (vs chronic ventilation and resuscitation). Interviewees were reluctant to disconnect patients from a ventilator.

CONCLUSIONS

Family members often want escalation of treatment for their ventilated relatives; however, most would not wish to be chronically ventilated or resuscitated under similar circumstances. Advance directives may reconcile people's wishes at the end of their own lives with their reticence to make decisions regarding others.

Age differences in survival outcomes and resource use for chronically critically ill patients

PURPOSE

Chronically critically ill (CCI) patients use a disproportionate amount of resources, yet little research has examined outcomes for older CCI patients. The purpose of this study was to compare outcomes (mortality, disposition, posthospital resource use) between older (> or =65 years) and middle-aged (45-64 years) patients who require more than 96 hours of mechanical ventilation while in the intensive care unit.

METHODS

Data from 2 prospective studies were combined for the present examination. In-hospital as well as posthospital discharge data were obtained via chart abstraction and interviews.

RESULTS

One thousand one hundred twenty-one subjects were enrolled; 62.4% (n = 700) were older. Older subjects had a 1.3 greater risk for overall mortality (from admission to 4 months posthospital discharge) than middle-aged subjects. The Acute Physiology Score (odds ratio [OR], 1.009), presence of diabetes (OR, 2.37), mechanical ventilation at discharge (OR, 3.17), and being older (OR, 2.20) were statistically significant predictors of death at 4 months postdischarge. Older subjects had significantly higher charges for home care services, although they spent less time at home (mean, 22.1 days) than middle-aged subjects (mean, 31.3 days) (P = .03).

CONCLUSION

Older subjects were at higher risk of overall mortality and used, on average, more postdischarge services per patient when compared with middle-aged subjects.

Profile and consequences of children requiring prolonged mechanical ventilation in three Brazilian pediatric intensive care units

OBJECTIVE

To describe the characteristics of children submitted to prolonged mechanical ventilation (MV), and evaluate their mortality, and associated factors as well as the potential impact at admissions to the pediatric intensive care unit (PICU).

METHODS

We conducted a retrospective study enrolling all children admitted to three Brazilian PICUs between January 2003 and December 2005 submitted to MV > or =21 days. The three selected PICUs were located in university-affiliated hospitals. From the medical charts were reported anthropometric data, diagnosis, ventilator parameters on the 21st day, length of MV, length of stay in the PICU, specific interventions (e.g., tracheostomy), and outcome.

RESULTS

One hundred eighty-four children (190 admissions) were submitted to prolonged MV (2.5% of all admissions to these 3 Brazilian PICUs), with a median age of 6 months. The mortality rate was 48% and the median time on MV was 32 days. Tracheostomy was performed on only 19% of the patients and, on average after 32 days of intubation. Mortality was associated with peak inspiratory pressure >25 cm H2O (odds ratio = 2.3; 1.1-5.1), fraction of inspired oxygen >0.5 (odds ratio = 6.3; 2.2-18.1), and vasoactive drug infusion (odds ratio = 2.6; 1.1-5.9) on the 21st day of MV. Seventy-six children (1% of the all admissions) were dependent on MV without other organ failures were 830 PICU admissions and were potentially prevented.

CONCLUSIONS

A small group of children admitted to the PICU requires prolonged MV. The elevated mortality rate is associated with higher ventilatory parameters and vasoactive drug support on the 21st day of MV. Stable children requiring prolonged MV in the PICU potentially prevent additional admissions of a large number of acute and unstable patients.

Predictors of successful weaning from prolonged mechanical ventilation in Taiwan

BACKGROUND

For adult patients on prolonged mechanical ventilation (PMV, >/=21 days), successful weaning has been attributed to various factors. The purpose of this study was to describe patient outcomes, weaning rates and factors in successful weaning at a hospital-based respiratory care center (RCC) in Taiwan.

METHODS AND RESULTS

This was a retrospective observational study performed in a 24-bed RCC over six years. A total of 1307 patients on PMV were included in the study. The overall survival rate was 62%. Fifty-six percent of patients were successfully weaned. Unsuccessfully weaned patients had higher MICU transfer rates, higher Acute Physiology and Chronic Health Evaluation II scores, longer duration of RCC stay, higher rates of being bed-ridden prior to admission, increased hemodialysis rates, higher modified Glasgow Coma Scale scores, higher rapid shallow breathing index, lower inspiratory pressure at residual volume (PImax) and lower blood urea nitrogen (BUN) and creatinine levels. Factors found to be associated with unsuccessful weaning were length of RCC stay (OR=1.04, P<0.001), modified GCS score (OR=0.93, P<0.046), PImax (OR=0.97, P<0.001), serum albumin concentration (OR=0.62, P<0.023) and BUN level (OR=1.01, P<0.002).

CONCLUSION

High rates of ventilator independence can be achieved in an RCC setting as an alternative to ICU care. Factors associated with unsuccessful weaning included longer duration of RCC stay, elevated BUN levels and lower modified GCS scores, serum albumin and PImax levels.

Response to hypercapnic challenge is associated with successful weaning from prolonged mechanical ventilation due to brain stem lesions

OBJECTIVE

We propose that higher airway occlusion pressure (P0.1) responses to hypercapnic challenge (HC) indicate less severe injury. The study aim was to determine whether P0.1 responses to HC were associated with successful weaning after prolonged mechanical ventilation (PMV) in patients with brainstem lesions and to determine a reference value for clinical use.

DESIGN AND SETTING

Forty-two patients with brainstem lesions on PMV were recruited. Breathing parameters and P0.1 were measured before HC. Three-minute HC challenges with increasing CO(2) concentrations were initiated and P0.1, respiratory rate, minute ventilation (V (e)), tidal volume (V (t)) and end tidal CO(2) were measured.

MEASUREMENTS AND RESULTS

Patients were classified into high (group I) and low (group II) response groups on the basis of P0.1 responses to HC. Increases in V (e) and V (t) after HC were significantly greater in group I patients (12.22 +/- 8.22 vs. 3.08 +/- 4.84 L/min, P < 0.001 and 399.11 +/- 278.18 vs. 110.54 +/- 18.275 ml, P < 0.001). P0.1 levels were significantly higher in group I compared to group II before HC (2.69 +/- 1.81 vs. 1.28 +/- 1.04 cmH(2)O, P = 0.003). The increase in P0.1 following HC was significantly greater in group I compared to group II patients (11.05 +/- 4.06 vs. 2.90 +/- 2.53 cmH(2)O, P < 0.001). Weaning success was significantly higher in group I compared to group II patients (72.2% vs. 33.3%, P = 0.02). A P0.1 increase of >6 cmH(2)O following HC was significantly associated with successful weaning.

CONCLUSIONS

Assessing the P.01 response to serial increases in the level of HC may be a safe means to ascertain whether patients with brainstem lesions are ready for ventilator weaning.

Sequential organ failure assessment score and comorbidity: valuable prognostic indicators in chronically critically ill patients

Chronically critically ill patients are defined as those who survive initial life-threatening, possibly reversible organ failure(s) but are unable to recover rapidly to a point at which they are fully independent of life support. Accordingly, these patients require mechanical ventilation and medical resources for a long time in an intensive care unit (ICU). The present study analysed demographic, clinical and survival data of chronically critically ill patients, to identify condition(s) related to poor prognosis. A total of 141 chronically critically ill patients were studied retrospectively over a two-year period (July 1, 2003 to June 30, 2005). Their mean lengths of stay in the ICU and in the hospital were 42.9+/-36.4 and 83.9+/-100.5 days respectively. ICU and six-month cumulative mortality rates were 42.6% and 75.9% respectively. Non-survivors had a significantly higher Sequential Organ Failure Assessment (SOFA) score than survivors on day 21 of ICU admission, as well as having significantly lower changes of SOFA scores between days three and 21. Multivariate analysis demonstrated that the SOFA score on day 21 and the Charlson Comorbidity Index were the best predictor of survival for six months after hospital discharge. The SOFA score on day 21 and comorbidity in the ICU appears to be a valuable prognostic indicators in chronically critically ill patients.

Prolonged acute mechanical ventilation and hospital bed utilization in 2020 in the United States: implications for budgets, plant and personnel planning

BACKGROUND

Adult patients on prolonged acute mechanical ventilation (PAMV) comprise 1/3 of all adult MV patients, consume 2/3 of hospital resources allocated to MV population, and are nearly twice as likely to require a discharge to a skilled nursing facility (SNF). Their numbers are projected to double by year 2020. To aid in planning for this growth, we projected their annualized days and costs of hospital use and SNF discharges in year 2020 in the US.

METHODS

We constructed a model estimating the relevant components of hospital utilization. We computed the total days and costs for each component; we also applied the risk for SNF discharge to the total 2020 PAMV population. The underlying assumption was that process of care does not change over the time horizon. We performed Monte Carlo simulations to establish 95% confidence intervals (CI) for the point estimates.

RESULTS

Given 2020 projected PAMV volume of 605,898 cases, they will require 3.6 (95% CI 2.7-4.8) million MV, 5.5 (95% CI 4.3-7.0) million ICU and 10.3 (95% CI 8.1-13.0) million hospital days, representing an absolute increase of 2.1 million MV, 3.2 million ICU and 6.5 million hospital days over year 2000, at a total inflation-adjusted cost of over $64 billion. Expected discharges to SNF are 218,123 (95% CI 177,268-266,739), compared to 90,928 in 2000.

CONCLUSION

Our model suggest that the projected growth in the US in PAMV population by 2020 will result in annualized increases of more than 2, 3, and 6 million MV, ICU and hospital days, respectively, over year 2000. Such growth requires careful planning efforts and attention to efficiency of healthcare delivery.

Intensive care unit tracheostomy: a snapshot of UK practice

Background and methods

Tracheostomy is a common procedure in intensive care patient management. The aim of this study was to capture the practice of tracheostomy in Intensive Care Units in the United Kingdom. A postal survey was sent to the lead clinicians of 228 general intensive care units (ICUs) throughout the United Kingdom excluding specialist units. We aimed to identify the current practice of tracheostomy, including timing of insertion, equipment used and post-operative care and follow-up.

Results

A response rate of 86.84% was achieved. Percutaneous tracheostomy continues to be favoured over surgical tracheostomy with less than 8% of ICUs opting for surgical tracheostomies > 50% of the time. 89% of units required only 2 operators to perform the technique and single stage dilatation is the technique of choice in 83% of units. The Ciaglia technique, which was strongly favoured less than a decade ago, is currently practiced in less than 5% of ICUs. Bronchoscopic guidance is an important adjunct to the technique of percutaneous tracheostomy with 80% of units using it routinely. Follow-up care of patients remains poor with 59% of ICUs not having routine follow-up once the patient has left the unit.

Conclusion

The practice of percutaneous tracheostomy remains the preferred technique within the UK. There seems to be a growing preference for single stage dilatational techniques. Timing of tracheostomy remains variable despite evidence to suggest benefit from an earlier procedure. Follow-up of tracheostomised patients after discharge from ICU is still low, which may mean significant morbidity from the procedure is being missed.

Determinants of long-term mortality after prolonged mechanical ventilation

STUDY OBJECTIVES

The poor long-term survival of patients requiring prolonged mechanical ventilation may be due to potentially modifiable factors. We therefore sought to assess the early determinants of long-term survival after discharge from a specialized respiratory unit.

METHODS

Eighty of 113 patients (71%) admitted to a respiratory care unit from June 2001 to August 2003 survived to discharge. Mortality outcomes and dates of death were determined by review of the records and survey in April 2005 of a national Death Master File. Potential determinants of survival after discharge were collected during the admission to the unit.

RESULTS

Fifty-five percent of patients died within the first year after discharge. Age of 65 years or older, sacral ulcers, a serum creatinine >124 micromol/L, and failure to wean were each individually associated with shorter survival. Age, skin integrity, and wean status on discharge remained independent determinants of survival in a multivariable analysis. In a post-hoc analysis, chronic irreversible neurologic diseases were also independently associated with poor long-term survival.

CONCLUSIONS

Mortality after discharge from a respiratory care unit is high. Interventions that may favorably impact long-term survival in these patients could target the modifiable factors identified, including measures that facilitate weaning and prevent or treat renal dysfunction and skin breakdown.

A prognostic model for one-year mortality in patients requiring prolonged mechanical ventilation

OBJECTIVE

A measure that identifies patients who are at high risk of mortality after prolonged ventilation will help physicians communicate prognoses to patients or surrogate decision makers. Our objective was to develop and validate a prognostic model for 1-yr mortality in patients ventilated for 21 days or more.

DESIGN

The authors conducted a prospective cohort study.

SETTING

The study took place at a university-based tertiary care hospital.

PATIENTS

Three hundred consecutive medical, surgical, and trauma patients requiring mechanical ventilation for at least 21 days were prospectively enrolled.

MEASUREMENTS AND MAIN RESULTS

Predictive variables were measured on day 21 of ventilation for the first 200 patients and entered into logistic regression models with 1-yr and 3-mo mortality as outcomes. Final models were validated using data from 100 subsequent patients. One-year mortality was 51% in the development set and 58% in the validation set. Independent predictors of mortality included requirement for vasopressors, hemodialysis, platelet count < or = 150 x 10(9)/L, and age > or = 50 yrs. Areas under the receiver operating characteristic curve for the development model and validation model were .82 (SE .03) and .82 (SE .05), respectively. The model had sensitivity of .42 (SE .12) and specificity of .99 (SE .01) for identifying patients who had > or = 90% risk of death at 1 yr. Observed mortality was highly consistent with both 3- and 12-mo predicted mortality. These four predictive variables can be used in a simple prognostic score that clearly identifies low-risk patients (no risk factors, 15% mortality) and high-risk patients (three or four risk factors, 97% mortality).

CONCLUSIONS

Simple clinical variables measured on day 21 of mechanical ventilation can identify patients at highest and lowest risk of death from prolonged ventilation.

Prolonged acute mechanical ventilation, hospital resource utilization, and mortality in the United States

OBJECTIVE

Adjusted costs of mechanical ventilation (MV) are $1,500 per patient-day. We compared the prevalence, characteristics, and outcomes of MV < 96 hrs (MV < 96) and prolonged acute MV (PAMV) of > or = 96 hrs' duration in a representative sample of U.S. hospital discharges.

DESIGN

A multicenter cross-sectional study.

SETTING

Nationally representative sample of U.S. hospital discharges.

PATIENTS

Adult hospital discharges were identified from the 2003 Nationwide Inpatient Sample, Healthcare Cost and Utilization Project from the Agency for Healthcare Research and Quality (AHRQ). PAMV was based on the presence of ICD-9 code 96.72, and MV < 96 hrs based on ICD-9 codes 96.70 and 96.71.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 31,340,578 discharges for adults (> or = 18 yrs), 2.4% had any MV, of which 469,168 (61%) had MV < 96, and 294,333 (39%) had PAMV. Patient demographics were similar for MV < 96 and PAMV. With the exception of acute myocardial infarction and chronic and end-stage renal disease without dialysis, the prevalence of coexisting conditions was higher in the PAMV group. Median length of stay (17 vs. 6 days) and hospital costs ($40,903 vs. $13,434) also were higher with PAMV vs. MV < 96. Although Agency for Healthcare Research and Quality disease severity and mortality probability were higher in the PAMV than MV < 96 group, actual mortality was similar between the two groups (34% vs. 35%).

CONCLUSIONS

There were nearly 300,000 PAMV discharges in the United States in 2003 at an annual aggregated hospital cost of > $16 billion, or nearly two thirds of the cost for all of the MV discharges. Despite a higher predicted mortality, patients requiring PAMV had the same likelihood of being discharged alive as those on shorter-term MV. These analyses will help inform health care decision-making and resource planning in the face of an aging population.

Rapid disuse atrophy of diaphragm fibers in mechanically ventilated humans

BACKGROUND

The combination of complete diaphragm inactivity and mechanical ventilation (for more than 18 hours) elicits disuse atrophy of myofibers in animals. We hypothesized that the same may also occur in the human diaphragm.

METHODS

We obtained biopsy specimens from the costal diaphragms of 14 brain-dead organ donors before organ harvest (case subjects) and compared them with intraoperative biopsy specimens from the diaphragms of 8 patients who were undergoing surgery for either benign lesions or localized lung cancer (control subjects). Case subjects had diaphragmatic inactivity and underwent mechanical ventilation for 18 to 69 hours; among control subjects diaphragmatic inactivity and mechanical ventilation were limited to 2 to 3 hours. We carried out histologic, biochemical, and gene-expression studies on these specimens.

RESULTS

As compared with diaphragm-biopsy specimens from controls, specimens from case subjects showed decreased cross-sectional areas of slow-twitch and fast-twitch fibers of 57% (P=0.001) and 53% (P=0.01), respectively, decreased glutathione concentration of 23% (P=0.01), increased active caspase-3 expression of 100% (P=0.05), a 200% higher ratio of atrogin-1 messenger RNA (mRNA) transcripts to MBD4 (a housekeeping gene) (P=0.002), and a 590% higher ratio of MuRF-1 mRNA transcripts to MBD4 (P=0.001).

CONCLUSIONS

The combination of 18 to 69 hours of complete diaphragmatic inactivity and mechanical ventilation results in marked atrophy of human diaphragm myofibers. These findings are consistent with increased diaphragmatic proteolysis during inactivity.

Acute and long-term survival in chronically critically ill surgical patients: a retrospective observational study

INTRODUCTION

Various cohort studies have shown that acute (short-term) mortality rates in unselected critically ill patients may have improved during the past 15 years. Whether these benefits also affect acute and long-term prognosis in chronically critically ill patients is unclear, as are determinants relevant to prognosis.

METHODS

We conducted a retrospective analysis of data collected from March 1993 to February 2005. A cohort of 390 consecutive surgical patients requiring intensive care therapy for more than 28 days was analyzed.

RESULTS

The intensive care unit (ICU) survival rate was 53.6%. Survival rates at one, three and five years were 61.8%, 44.7% and 37.0% among ICU survivors. After adjustment for relevant covariates, acute and long-term survival rates did not differ significantly between 1993 to 1999 and 1999 to 2005 intervals. Acute prognosis was determined by disease severity during ICU stay and by primary diagnosis. However, only the latter was independently associated with long-term prognosis. Advanced age was an independent prognostic determinant of poor short-term and long-term survival.

CONCLUSION

Acute and long-term prognosis in chronically critically ill surgical patients has remained unchanged throughout the past 12 years. After successful surgical intervention and intensive care, long-term outcome is reasonably good and is mainly determined by age and underlying disease.