Comments
Abstract
Rationale: Intermediate care (i.e., step-down or progressive care) is an alternative to the intensive care unit (ICU) for patients with moderate severity of illness. The adoption and current use of intermediate care is unknown.
Objectives: To characterize trends in intermediate care use among U.S. hospitals.
Methods: We examined 135 million acute care hospitalizations among elderly individuals (≥65 yr) enrolled in fee-for-service Medicare (U.S. federal health insurance program) from 1996 to 2010. We identified patients receiving intermediate care as those with intensive care or coronary care room and board charges labeled intermediate ICU.
Measurements and Main Results: In 1996, a total of 960 of the 3,425 hospitals providing critical care billed for intermediate care (28%), and this increased to 1,643 of 2,783 hospitals (59%) in 2010 (P < 0.01). Only 8.2% of Medicare hospitalizations in 1996 were billed for intermediate care, but billing steadily increased to 22.8% by 2010 (P < 0.01), whereas the percentage billed for ICU care and ward-only care declined. Patients billed for intermediate care had more acute organ failures diagnoses codes compared with general ward patients (22.4% vs. 15.8%). When compared with patients billed for ICU care, those billed for intermediate care had fewer organ failures (22.4% vs. 43.4%), less mechanical ventilation (0.9% vs. 16.7%), lower mean Medicare spending ($8,514 vs. $18,150), and lower 30-day mortality (5.6% vs. 16.5%) (P < 0.01 for all comparisons).
Conclusions: Intermediate care billing increased markedly between 1996 and 2010. These findings highlight the need to better define the value, specific practices, and effective use of intermediate care for patients and hospitals.
Although intermediate care (i.e., step-down, transitional care, or progressive care) has been described as an alternative to care provided in the intensive care unit for patients with moderate severity of illness, current use of such care is poorly characterized.
Our study found a marked increase in the percentage of hospitals billing for intermediate care and patients receiving intermediate care between 1996 and 2010. The findings suggest there has been a large increase in the amount of care delivered in intermediate care settings despite a limited literature describing the impact of intermediate care on patient outcomes or cost savings to hospitals.
As the U.S. population ages, the demand for critical care services is expected to increase (1), potentially straining existing intensive care unit (ICU) capacity. Since their initial description in the 1980s, intermediate care units (i.e., step-down, transitional, or progressive care) have offered an alternative model for delivering care to hospitalized patients—a less resource-intensive setting than the ICU that still provides a higher level of care than general hospital wards (2). To maximize financial margins, hospitals may have substantial motivation to shift patients with more moderate illness severity to less costly alternatives to the ICU, such as intermediate care, provided these settings can deliver similar care with less resource use per day. In contrast, if intermediate care is predominantly used as step-up monitoring for ward patients, its emergence may raise costs without necessarily improving outcomes. Unfortunately, most studies to date examining the effect of intermediate care on patient outcomes and hospital costs are limited by single-center, pre-post, or retrospective designs, and have yielded mixed results (3–7).
The lack of national data on the epidemiology of intermediate care has hindered broader efforts to understand its impact on outcomes and costs. Although hospitals providing care to Medicare beneficiaries submit yearly data on their total hospital and ICU bed numbers, these data do not distinguish intermediate care units from ICU beds (8). Moreover, definitions of what constitutes intermediate care may vary among hospitals, ranging from simply providing telemetry and higher nursing ratios to the provision of life-support therapies including mechanical ventilation; unlike critical care, there is no standardized definition from the U.S. Department of Health and Human Services (9). Together, these issues preclude a more comprehensive evaluation of how hospitals are using intermediate care, and evidence-based policies or organizational recommendations for intermediate care.
In the current study, we sought to characterize the use of intermediate care for patients at acute care hospitals using Medicare billing claims from 1996 through 2010. Beginning in 1996, unique billing codes for intermediate care (labeled “intermediate ICU”) have been available for reporting, and these codes were intended to capture care provided in a specific intermediate care setting, distinct from the ICU or general ward (10, 11). Additionally, we sought to characterize patients billed for intermediate care, to determine whether these patients seem distinct from ward and ICU patients with regard to severity of illness and outcomes. We hypothesized that there was a significant increase in use of intermediate care among Medicare beneficiaries over the study period and that patients billed for intermediate care have a distinct severity of illness and outcomes compared with ward and ICU patients. Some of the results in this study have been previously reported in the form of an abstract (12).
We performed a retrospective cohort study of all acute care hospitalizations among elderly (age, ≥65) fee-for-service Medicare beneficiaries from 1996 to 2010. Medicare is a federal program that provides health insurance for adults aged 65 years and older and for those with disabilities or end-stage renal disease in the United States. Approximately 93% of people in the United States over 65 are Medicare beneficiaries (13), most of which are enrolled in fee-for-service plans.
We identified patients billed for an intermediate care or an ICU care during their hospitalization using the Medicare Provider and Analysis Review (MedPAR) file revenue center codes. Room and board charges during hospital stays are captured in these codes for both intensive care and coronary care and include separate codes for ICU and intermediate care stays. In 1996, the labels of revenue center codes 0206 and 0214 were changed from “post-ICU” to “intermediate ICU” and “post-CCU” (coronary care unit) to “intermediate CCU,” respectively, to better capture time spent in an intermediate care unit. The former names were frequently misunderstood by coders to mean any days in the hospital after an ICU stay rather than days spent specifically in intermediate care, distinct from the ICU or general ward (10).
MedPAR files contain a single ICU indicator field and coronary care indicator field. A patient charged for more than one type of ICU care or coronary care during a hospitalization is assigned the code with the higher aggregate charge. For example, if a patient received care in both an ICU and intermediate care unit, but spent more days and had a higher charge for the time spent in intermediate care, then intermediate care is recorded in MedPAR as the location where they received care. Because MedPAR ICU coding is mutually exclusive, patients were assigned to one of three categories (ICU care, intermediate care, or ward care) for the purposes of analysis (Table 1). Patients who were analyzed in the intermediate care category could have potentially been billed for ICU care as well, but the ICU charge would have been lower than the intermediate care charge. Patients assigned to the ward care category had neither an ICU nor intermediate care billing charge during their hospitalization.
| Categories | Medicare Data | New York State Data |
|---|---|---|
| Ward care | No ICU or coronary care revenue center codes | No ICU or coronary care revenue center codes |
| Intermediate care | Presence of an “intermediate ICU” or “intermediate CCU” revenue center code* | Presence of an “intermediate ICU” or “intermediate CCU” revenue center code |
| ICU care | Presence of an ICU or coronary care revenue center code not labeled “intermediate”* | Presence of any ICU or coronary care revenue center code not labeled “intermediate” |
| Intermediate and ICU care | Cannot identify | Presence of an “intermediate ICU” or “intermediate CCU” revenue center code AND any ICU or coronary care revenue center code not labeled “intermediate” |
We collapsed ICU and coronary care codes in MedPAR so that charges labeled “intermediate ICU” and “intermediate CCU” were defined as intermediate care, and all other ICU and coronary care unit charges were defined as ICU care. Throughout the manuscript, we use the term “critical care” broadly when referring to any patients who were billed for ICU or intermediate care, and the term “ward” for general hospital care, when referring to patients not billed for either ICU or intermediate care.
We used the Healthcare Cost Report Information System (HCRIS) records from 1996 through 2010 to identify acute care hospitals capable of providing services to critically ill patients. Similar to previous work, we excluded hospitals reporting less than 2 months of fiscal information, less than 10 total inpatient days in a fiscal year, less than 10 general hospital beds, and hospitals without ICU beds (14–16). After linking these hospital files to patient billing records, we defined hospitals that provided intermediate care as those billing intermediate care in five or more patient records during a calendar year.
We used HCRIS files to compare characteristics of hospitals billing for intermediate care services in 2010 with those that did not bill for intermediate care. The hospital characteristics we examined included hospital ownership status (for-profit, nonprofit, and government), total number of hospital and ICU beds, whether the hospital had a graduate medical education accredited residency program, and hospital location (Northeast, Midwest, South, and West Coast).
We compared characteristics of patients billed for intermediate care with patients billed for ICU care and patients who received only general medical ward care, including their age, sex, and race (black, white, and other), International Classification of Diseases-9-CM diagnosis and procedure codes, diagnosis-related group codes, length of stay, hospital charges and Medicare payment amount, outcomes, and discharge destinations. Procedure use was identified using International Classification of Diseases-9-CM procedure codes, including invasive (96.7X) and noninvasive (93.90) mechanical ventilation, central venous catheterization (38.93), blood transfusion (99.0X), and hemodialysis (39.95). We characterized comorbidity using secondary diagnosis codes (17). We characterized severity of illness using International Classification of Diseases-9-CM codes for organ failure as defined by Angus and colleagues (18). We defined hospitalizations as primarily medical or surgical using diagnosis-related group codes.
To determine the extent that MedPAR underrepresents or overrepresents intermediate care billing because of its mutually exclusive coding of ICU care, and to test the generalizability of the results to the nonelderly, we examined hospital discharge data in New York State (19). Details of this analysis can be found in the Methods section of the online supplement.
To estimate the relative costs of ward care, intermediate care, and ICU care we used room and board charges and the number of hospital days associated with each revenue center. For example, to estimate the daily cost of ICU care, we divided the total charge captured in the ICU room and board revenue center field by the number of days spent in an ICU. We then used HCRIS hospital-specific cost-to-charge ratios to estimate costs. We used a similar approach for intermediate care and ward care.
We counted the total numbers of acute care hospitalizations among fee-for-service Medicare beneficiaries for each year in the study period, and the number with an ICU or intermediate care billing code, stratified by age, sex, and race. Because the unit of analysis was hospitalizations, individual patients were counted multiple times if they had multiple hospitalizations in the same year. Because the sex, age, and racial distribution of hospitalized beneficiaries changed over the study period, we used Poisson regression to adjust for these changes when calculating rates of ICU or intermediate care billing per total number of hospitalizations each year. We present these yearly rates as a stacked bar graph. We plotted the yearly number of hospital’s billing for intermediate care among all hospitals identified as capable of providing critical care.
We calculated hospital-specific, reliability-adjusted intermediate care billing rates in 2010 by fitting an empty multilevel logistic regression with intermediate care stay as the outcome and hospital as the random intercept (20, 21). The purpose of an empty multilevel model is to estimate hospital-specific differences in an outcome variable adjusting only for the reliability of outcome estimates derived from few cases. We displayed hospital-specific intermediate care billing rates in a histogram. To compare hospitals with lower and higher intermediate care billing, we grouped hospitals into quartiles based on their intermediate care billing rates, setting first quartile hospitals as those with the lowest rate.
We compared patients and hospital characteristics using chi-square or analysis of variance as appropriate. To prevent a patient from being included in multiple categories when comparing the characteristics of patients billed for ward-only care, intermediate care, and ICU care in 2010, we analyzed the first admission if a patient was hospitalized multiple times. All data management and analysis was conducted using SAS 9.3 (SAS Institute, Cary, NC) and Stata 13 (StataCorp, College Station, TX). The institutional review board of the University of Michigan approved the study (HUM00053488).
Among 135 million eligible Medicare admissions between 1996 and 2010, a total of 19.2 million were billed for intermediate care (14.3% of admissions) and 25.6 million were billed for ICU care (19.0% of admissions). The percentage of patients billed for intermediate care increased markedly over the study period, whereas the percentage billed for ICU care and ward-only care decreased (Figure 1). In 1996, just 8.19% (95% confidence interval, 8.17–8.21%) of patients hospitalized were billed for intermediate care, whereas in 2010, a total of 22.83% (95% confidence interval, 22.80–22.87%) of patients hospitalized were billed for intermediate care.
Figure 1. Trends in billing for intermediate care and intensive care unit (ICU) hospitalizations among Medicare beneficiaries, 1996–2010.
[More] [Minimize]Because Medicare files contain mutually exclusive billing records for critical care, if patients increasingly received both ICU and intermediate care, but were only recorded as receiving intermediate care, an apparent decline in ICU care and increase in intermediate care would be an artifact. However, this was not the case in New York State all-payer data from 1998 to 2010, where we identified only a small percentage of patients billed for both ICU and intermediate care, a rate that varied from less than 0.1% in 1998 to 4.6% in 2010 (P < 0.01) but remained quite low. Similar to the trend in Medicare beneficiaries, the percentage of patients over 18 years of age in New York who were billed for intermediate care rose dramatically from 1998 to 2010 (see Figure E1 in the online supplement).
There were notable differences between Medicare beneficiaries billed for intermediate care, ICU care, or ward care alone at hospitals in 2010 (Table 2). Patients billed for intermediate care had higher rates of comorbid illness (mean number, 2.5 vs. 2.3; P < 0.01), higher rates of acute organ failures (22.4% vs. 15.8%; P < 0.01), and slightly longer hospital stays compared with ward patients. However, compared with patients billed for ICU care, patients billed for intermediate care had lower severity of illness, including lower rates of acute organ failure (22.4% vs. 43.4%; P < 0.01). They were also less likely to receive invasive procedures, such as invasive mechanical ventilation (0.9% vs. 16.7%; P < 0.01). Patient’s billed for intermediate care also had lower total mean hospital costs ($10,999 vs. $23,240; P < 0.01), lower mean Medicare payment ($9,016 vs. $18,803; P < 0.01), and lower 30-day mortality (5.8% vs. 16.5%; P < 0.01) than patients billed for ICU care.
| Characteristics* | Ward Care | Intermediate Care | ICU Care |
|---|---|---|---|
| No. hospitalizations† | 2,033,360 | 1,046,936 | 553,600 |
| Sex, % | |||
| Male | 39.6 | 44.8 | 50.7 |
| Female | 60.4 | 55.2 | 49.3 |
| Age, yr, mean | 77.9 | 78.5 | 77.1 |
| Age, % | |||
| 65–74 yr | 38.9 | 34.8 | 41.2 |
| 75–84 yr | 36.0 | 37.2 | 37.5 |
| 85+ yr | 25.1 | 28.0 | 21.3 |
| Race, % | |||
| White | 86.2 | 84.3 | 85.4 |
| Black | 9.4 | 9.8 | 9.3 |
| Other | 4.4 | 5.9 | 5.3 |
| No. comorbidities, median (IQR) | 2 (1–3) | 3 (2–4) | 2 (1–3) |
| Select comorbidities, % | |||
| Congestive heart failure | 11.4 | 21.7 | 20.8 |
| Chronic pulmonary disease | 16.3 | 18.6 | 18.3 |
| Renal failure | 11.0 | 14.5 | 11.9 |
| Diabetes | 22.7 | 24.5 | 20.0 |
| Malignancy | 6.8 | 5.2 | 6.3 |
| Hospitalization type, % | |||
| Medical | 64.1 | 76.1 | 52.0 |
| Surgical | 35.9 | 23.9 | 48.0 |
| Organ failure during stay, % | 15.8 | 22.4 | 43.4 |
| Organ failure type, % | |||
| Cardiovascular | 3.5 | 6.0 | 15.7 |
| Pulmonary | 0.2 | 0.9 | 16.7 |
| Renal | 10.0 | 14.5 | 23.7 |
| Invasive procedure use, % | |||
| Invasive mechanical ventilation | 0.2 | 0.9 | 16.7 |
| Noninvasive mechanical ventilation | 0.5 | 1.53 | 3.86 |
| Central venous catheter | 3.0 | 4.3 | 16.1 |
| Hemodialysis | 1.5 | 2.2 | 3.2 |
| Transfusion | 9.3 | 9.0 | 16.8 |
| Outcomes | |||
| Length of stay, d, median (IQR) | 3 (2–6) | 4 (2–6) | 6 (3–10) |
| Total hospital charges, $, mean (SD) | 31,479 (29,954) | 43,350 (47,412) | 88,064 (10,9575) |
| Total hospital costs, $, mean (SD) | 8,684 (7,414) | 10,999 (11,212) | 23,240 (26,086) |
| Medicare payment, $, mean (SD) | 7,746 (6,248) | 8,514 (8,807) | 18,150 (21,939) |
| In-hospital mortality, % | 1.6 | 2.3 | 13.2 |
| 30-d mortality, % | 4.5 | 5.6 | 16.5 |
| Discharge destination, % | |||
| Home | 69.2 | 71.7 | 60.3 |
| Skilled care facility | 25.9 | 22.5 | 31.1 |
| Other | 4.9 | 5.8 | 8.6 |
The average daily room and board costs were $402 (SD, 243) for ward care, $634 (SD, 375) for intermediate care, and $867 (SD, 502) for ICU care (P < 0.01 for all pairwise comparisons). Compared with daily ward care costs, this represented a relative cost increase of 58% for intermediate care and 116% for ICU care.
Among hospitals, there was a marked increase in intermediate care billing over the study period (Figure 2). In 1996, of the 3,425 hospitals providing critical care, 960 (28%) of hospitals billed for intermediate care. In 2010, of the 2,783 hospitals providing critical care, 1,643 (59%) billed for intermediate care. There was also a wide range of intermediate care billing rates at individual hospitals (Figure 3; see Figures E2 and E3). The median hospital billed intermediate care to 66.8% of patients receiving critical care (interquartile range, 47.5–77.1%).
Figure 2. Trends in billing for intermediate care among hospitals providing critical care, 1996–2010.
[More] [Minimize]
Figure 3. Hospital-specific rates of intermediate care billing among Medicare hospitalizations billed for any critical care (intensive care unit or intermediate care) in 2010.
[More] [Minimize]Characteristics of hospitals that more often billed for intermediate care included for-profit status, larger size, located on the West Coast, and teaching hospitals (Table 3). ICU patients at hospitals that billed for intermediate care had a higher severity of illness, including a higher percentage with organ failure and a higher percentage requiring mechanical ventilation. Mortality rates and Medicare spending were also higher for ICU patients at hospitals that billed intermediate care. There were only minor differences in the characteristics of hospitals that billed for intermediate care at lower versus higher rates (see Table E1). However, ICU patients at hospitals with high rates of intermediate care billing had higher severity of illness compared with ICU patients at hospitals with lower rates of intermediate care billing.
| Hospitals Billing for Intermediate Care* | ||
|---|---|---|
| No | Yes | |
| Hospital characteristics | ||
| No. hospitals | 1,140 | 1,643 |
| Hospital ownership, % | ||
| Nonprofit | 63.7 | 63.4 |
| Profit | 17.6 | 24.7 |
| Government | 18.8 | 12.0 |
| Total hospital beds, % | ||
| <100 | 47.5 | 16.3 |
| 100–399 | 46.7 | 66.5 |
| 400+ | 5.8 | 17.3 |
| Total ICU beds, % | ||
| <10 | 52.2 | 19.0 |
| 10–30 | 29.9 | 36.9 |
| >30 | 17.9 | 44.1 |
| Teaching hospital, % | ||
| None | 72.3 | 58.9 |
| GME accredited residency | 27.7 | 41.1 |
| Region, % | ||
| Northeast | 21.7 | 13.6 |
| Midwest | 23.0 | 23.1 |
| South | 40.7 | 39.8 |
| West | 14.7 | 23.6 |
| Characteristics of ICU patients | ||
| No. patients† | 287,228 | 553,984 |
| Any organ failure, % | 37.6 | 43.3 |
| Invasive mechanical ventilation, % | 12.3 | 16.7 |
| Length of stay, d, median (IQR) | 5 (3–8) | 6 (3–10) |
| Medicare spending, $, mean | 14,675 | 18,145 |
| 30-d mortality, % | 14.1 | 16.5 |
Major increases in billing for intermediate care occurred among hospitalized Medicare beneficiaries between 1996 and 2010. The percentage of patients billed for ICU and ward care decreased over time, suggesting that intermediate care may be absorbing patients from both the ICU and general ward. In addition, our study goes against the conventional narrative of increasing ICU use among hospitals (14, 15, 22), and suggests that the rise is in intermediate care and not ICU care. Patients billed for intermediate care seemed distinct from typical ICU and ward patients, with greater severity of illness compared with patients who received general ward care, but lower severity than those receiving ICU care. This suggests these patients are occupying beds aimed at caring for a differentiated population with a moderate degree of illness between patients on the ward or ICU. However, these beds could be located on the floor, ICU, or in a stand-alone intermediate care unit. At the hospital level, we found a significant increase of the percentage of hospitals billing for intermediate care during the study period, but also found substantial variation in rates of intermediate billing across hospitals.
Our study demonstrates a temporal increase in intermediate care use in U.S. hospitals. Among the 2,783 acute-care hospitals with critical care capabilities studied in 2010, we found that 59% were billing for intermediate care, an increase from 29% of hospitals in 1996. However, despite its clear rise, existing public health and administrative surveillance systems are inadequate to determine what constitutes intermediate care at individual hospitals or to determine the location within hospitals where this care is being delivered. Hospitals could be billing for intermediate care in a physically distinct intermediate care unit, within an ICU, or within a general hospital ward with enhanced resources. Nevertheless, we found face and predictive validity to the claim that intermediate care represents an established and growing care model, because intermediate care patients lie between ICU and ward patients with respect to severity of illness, procedure use, and mortality.
Our study builds on previous investigations of intermediate care use among Medicare beneficiaries. In a study of ICU use among Medicare beneficiaries between 1995 and 2000, Halpern and coworkers (11) found that the cumulative number of days per year that Medicare beneficiaries spent in ICUs was 40–47% higher when MedPAR data were aggregated compared with HCRIS data. This discrepancy was caused by the additional counting of intermediate care as ICU days in MedPAR (11). In addition, a recent study examining intensive care use among patients with lung cancer found that rates of ICU use among this population were rising largely because of increasing use of intermediate care (23).
The growing use of intermediate care among hospitals is perhaps surprising given the uncertain clinical impact, safety, or economic benefit of intermediate care (4, 24). There are several plausible mechanisms in which intermediate care could drive down hospital costs. Medicare reimburses hospitals for care provided to Medicare beneficiaries based on patient diagnosis-related groupings, and the location where care was provided is not a part of this payment equation (25). In theory, if an intermediate care unit has lower fixed costs than a traditional ICU because of lower staff to patient ratios, hospitals could save money by shifting ICU patients to intermediate care. However, our findings suggest a substantial portion of patients receiving intermediate care are being shifted from the hospital ward, an area likely to have lower fixed costs than intermediate care.
Shifting patients from an ICU to intermediate care bed may also have more complex effects on overall hospital costs when ICU beds are made available for sicker and potentially more expensive patients. This occurred, for example, during a single-center study analyzing the effect of opening an intermediate care unit at a tertiary care hospital in the Netherlands (26). The study authors found that overall hospital costs increased after the intermediate care unit opened, because the ICU was able to accept more patients with high acuity. Our study also revealed that ICU patients in hospitals billing for intermediate care had higher mortality and Medicare spending than ICU patients at hospitals without intermediate care. By improving access to the ICU for patients with a high risk of death through moving other patients to intermediate beds, hospitals may paradoxically harm their margins by prolonging care for patients who may have otherwise died without ICU care (27).
The growing use of intermediate care also highlights a need to further investigate when intermediate care is a safe alternative to ICU care. In general, studies have not found intermediate care to be associated with differences in patient outcomes for certain surgical patients (28, 29), patients with acute myocardial infarction (30), or among patients recovering from general critical illnesses after an ICU stay (3, 5). However, one study examining organizational factors among hospitals caring for patients with sepsis found the presence of an intermediate care unit was associated with a 26% increase in the odds of hospital mortality (6), whereas another found the presence of an intermediate care unit was associated with 37% lower odds for hospital mortality among ICU patients (7). An important caveat when interpreting these studies is their high risk for bias from confounding by the indication for intermediate care that results when risk adjustment is inadequate (31). The paucity of evidence and the mixed results of existing studies examining the use of intermediate care may explain why guidelines for intermediate care triage have not been updated since 1998 (32).
Our study should be interpreted in the context of several limitations. We cannot attribute intermediate care billing to care received in an administratively separate unit, nor has the intermediate care revenue center code been validated as a way to identify patients that received a distinctly intermediate level of care during their hospital stay. Because intermediate care is not well defined, there is likely variation in how hospitals use and bill for intermediate care. Future work validating intermediate care beds collected by the American Hospital Association annual survey (33), or novel assessments of intermediate care capacity, may be helpful for characterizing the growth of intermediate care beds. However, clear definitions of what constitutes an intermediate care unit would improve the interpretability of these results. We were unable to describe the timing of intermediate care use within a hospital stay; thus, we cannot say whether hospitals used intermediate care in a step-up (floor to intermediate care) or step-down (ICU to intermediate care) manner. Finally, our primary analysis relied on Medicare data, which are limited to patients older than 64. However, analysis of New York State inpatient data showed a similar rise in the use of intermediate care billing among all hospitalized adults.
In conclusion, we found a striking increase in the number of Medicare beneficiaries billed for intermediate care during hospitalizations between 1996 and 2010. Intermediate care may offer a lower cost and safe alternative to ICU care for certain hospitalized patients, but could also represent an expansion of low value services further driving up the costs of hospital care. Our findings emphasize a pressing need to better define intermediate care, and to better understand its value for hospitals and patients. As patients increasingly receive intermediate care, it is imperative to determine whether it is a cost-effective alternative to care delivered elsewhere in the hospital.
| 1. | Angus DC, Kelley MA, Schmitz RJ, White A, Popovich J Jr; Committee on Manpower for Pulmonary and Critical Care Societies (COMPACCS). Caring for the critically ill patient. Current and projected workforce requirements for care of the critically ill and patients with pulmonary disease: can we meet the requirements of an aging population? JAMA 2000;284:2762–2770. |
| 2. | Prin M, Wunsch H. The role of stepdown beds in hospital care. Am J Respir Crit Care Med 2014;190:1210–1216. |
| 3. | Ranzani OT, Zampieri FG, Taniguchi LU, Forte DN, Azevedo LC, Park M. The effects of discharge to an intermediate care unit after a critical illness: a 5-year cohort study. J Crit Care 2014;29:230–235. |
| 4. | Vincent JL, Rubenfeld GD. Does intermediate care improve patient outcomes or reduce costs? Crit Care 2015;19:89. |
| 5. | Wunsch H, Harrison DA, Jones A, Rowan K. The impact of the organization of high-dependency care on acute hospital mortality and patient flow for critically ill patients. Am J Respir Crit Care Med 2015;191:186–193. |
| 6. | Peelen L, de Keizer NF, Peek N, Scheffer GJ, van der Voort PH, de Jonge E. The influence of volume and intensive care unit organization on hospital mortality in patients admitted with severe sepsis: a retrospective multicentre cohort study. Crit Care 2007;11:R40. |
| 7. | Capuzzo M, Volta C, Tassinati T, Moreno R, Valentin A, Guidet B, Iapichino G, Martin C, Perneger T, Combescure C, et al.; Working Group on Health Economics of the European Society of Intensive Care Medicine. Hospital mortality of adults admitted to intensive care units in hospitals with and without intermediate care units: a multicentre European cohort study. Crit Care 2014;18:551. |
| 8. | United States Department of Health and Human Services. Centers for Medicare and Medicaid Services: cost reports [accessed 2015 Jun 5]. Available from: http://www.cms.gov/Research-Statistics-Data-and-Systems/Downloadable-Public-Use-Files/Cost-Reports/ |
| 9. | US Department of Health and Human Services. AHRQ releases standardized hospital bed definitions [accessed 2015 Jun 16]. Available from: http://archive.ahrq.gov/research/havbed/definitions.htm |
| 10. | Research data assistance center. Medpar intensive care unit (ICU) indiator code [accessed 2015 Jun 4]. Available from: http://www.resdac.org/cms-data/variables/MEDPAR-Intensive-Care-Unit-ICU-Indicator-Code |
| 11. | Halpern NA, Pastores SM, Thaler HT, Greenstein RJ. Critical care medicine use and cost among Medicare beneficiaries 1995-2000: major discrepancies between two United States federal Medicare databases. Crit Care Med 2007;35:692–699. |
| 12. | Sjoding MW, Prescott HC, Wunsch H, Iwashyna TJ, Cooke CR. Increased proportion of Medicare beneficiaries are cared for in intermediate-intensive care unit settings [abstract]. Am J Respir Crit Care Med 189;2014:A4533. |
| 13. | Department of Health and Human Services. A profile of older Americans: 2012 [accessed 2015 Mar 12]. Available from: http://www.aoa.gov/Aging_Statistics/Profile/2012/docs/2012profile.pdf |
| 14. | Halpern NA, Pastores SM. Critical care medicine in the United States 2000-2005: an analysis of bed numbers, occupancy rates, payer mix, and costs. Crit Care Med 2010;38:65–71. |
| 15. | Halpern NA, Pastores SM, Greenstein RJ. Critical care medicine in the United States 1985-2000: an analysis of bed numbers, use, and costs. Crit Care Med 2004;32:1254–1259. |
| 16. | Wallace DJ, Angus DC, Seymour CW, Barnato AE, Kahn JM. Critical care bed growth in the United States. A comparison of regional and national trends. Am J Respir Crit Care Med 2015;191:410–416. |
| 17. | Elixhauser A, Steiner C, Harris DR, Coffey RM. Comorbidity measures for use with administrative data. Med Care 1998;36:8–27. |
| 18. | Angus DC, Linde-Zwirble WT, Lidicker J, Clermont G, Carcillo J, Pinsky MR. Epidemiology of severe sepsis in the United States: analysis of incidence, outcome, and associated costs of care. Crit Care Med 2001;29:1303–1310. |
| 19. | Agency for Healthcare Research and Quality. Healthcare cost and utilization project. Overview of the state inpatient databases (SID) [accessed 2015 Jun 5]. Available from: http://www.hcup-us.ahrq.gov/sidoverview.jsp |
| 20. | Gershengorn HB, Iwashyna TJ, Cooke CR, Scales DC, Kahn JM, Wunsch H. Variation in use of intensive care for adults with diabetic ketoacidosis. Crit Care Med 2012;40:2009–2015. |
| 21. | Dimick JB, Staiger DO, Birkmeyer JD. Ranking hospitals on surgical mortality: the importance of reliability adjustment. Health Serv Res 2010;45:1614–1629. |
| 22. | Milbrandt EB, Kersten A, Rahim MT, Dremsizov TT, Clermont G, Cooper LM, Angus DC, Linde-Zwirble WT. Growth of intensive care unit resource use and its estimated cost in Medicare. Crit Care Med 2008;36:2504–2510. |
| 23. | Cooke CR, Feemster LC, Wiener RS, O’Neil ME, Slatore CG. Aggressiveness of intensive care use among patients with lung cancer in the Surveillance, Epidemiology, and End Results-Medicare registry. Chest 2014;146:916–923. |
| 24. | Keenan SP, Massel D, Inman KJ, Sibbald WJ. A systematic review of the cost-effectiveness of noncardiac transitional care units. Chest 1998;113:172–177. |
| 25. | Centers for Medicare & Medicaid Services. Acute inpatient PPS. 2015 [accessed 2015 Aug 5]. Available from: https://www.cms.gov/Medicare/Medicare-Fee-for-Service-Payment/AcuteInpatientPPS/index.html |
| 26. | Solberg BC, Dirksen CD, Nieman FH, van Merode G, Poeze M, Ramsay G. Changes in hospital costs after introducing an intermediate care unit: a comparative observational study. Crit Care 2008;12:R68. |
| 27. | Joynt GM, Gomersall CD, Tan P, Lee A, Cheng CA, Wong EL. Prospective evaluation of patients refused admission to an intensive care unit: triage, futility and outcome. Intensive Care Med 2001;27:1459–1465. |
| 28. | Bellomo R, Goldsmith D, Uchino S, Buckmaster J, Hart G, Opdam H, Silvester W, Doolan L, Gutteridge G. A before and after trial of the effect of a high-dependency unit on post-operative morbidity and mortality. Crit Care Resusc 2005;7:16–21. |
| 29. | Jones HJ, Coggins R, Lafuente J, de Cossart L. Value of a surgical high-dependency unit. Br J Surg 1999;86:1578–1582. |
| 30. | Fiebach NH, Cook EF, Lee TH, Brand DA, Rouan GW, Weisberg M, Goldman L. Outcomes in patients with myocardial infarction who are initially admitted to stepdown units: data from the Multicenter Chest Pain Study. Am J Med 1990;89:15–20. |
| 31. | Sjoding MW, Luo K, Miller MA, Iwashyna TJ. When do confounding by indication and inadequate risk adjustment bias critical care studies? A simulation study. Crit Care 2015;19:195. |
| 32. | Nasraway SA, Cohen IL, Dennis RC, Howenstein MA, Nikas DK, Warren J, Wedel SK; American College of Critical Care Medicine of the Society of Critical Care Medicine. Guidelines on admission and discharge for adult intermediate care units. Crit Care Med 1998;26:607–610. |
| 33. | American Hospital Association. 2009 American Hospital Association Annual Survey. Chicago, IL: American Hospital Association; 2009. p. 15. |
Supported by NHLBI grant T32HL007749 (M.W.S., T.S.V., H.C.P.), National Institute on Aging grant K08AG038477 (H.W.), Veterans Affairs Health Services Research and Development grant IIR 11-109 (T.J.I.), National Institutes of Health grant R21AG044752 (T.J.I.), and Agency for Healthcare Research and Quality grant K08HS020672 (C.R.C.).
Author Contributions: M.W.S. and C.R.C. contributed to the study design, analysis and interpretation of data, writing and revising the manuscript, and approval of the final manuscript. T.S.V., H.C.P., H.W., and T.J.I. contributed to the analysis and interpretation of data, revising the manuscript for important intellectual content, and approval of the final manuscript.
This article has an online supplement, which is accessible from this issue's table of contents at www.atsjournals.org
Originally Published in Press as DOI: 10.1164/rccm.201506-1252OC on September 15, 2015
Author disclosures are available with the text of this article at www.atsjournals.org.
