By Betty Tran, MD, MSc
Assistant Professor of Medicine, Pulmonary and Critical Care Medicine, Rush University Medical Center, Chicago
Dr. Tran reports no financial relationships relevant to this field of study.
SYNOPSIS: Among patients who have spent at least three days in an ICU and required even brief mechanical ventilation and/or vasopressor support, almost half are dead and only one-third return to their baseline at six months. Several factors present on the first day of admission are associated with not returning to baseline status.
SOURCE: Detsky ME, Harhay MO, Bayard DF, et al. Six-month morbidity and mortality among ICU patients receiving life-sustaining therapy: A prospective cohort study. Ann Am Thorac Soc 2017 Jun 16. doi: 10.1513/AnnalsATS.201611-875OC. [Epub ahead of print].
Limited data are available concerning long-term outcomes of a general ICU population that could inform ICU discussions with patients and surrogates regarding expectations and prognosis. In this prospective cohort study of five ICUs (three medical, two surgical) within the University of Pennsylvania Health System, Detsky et al aimed to describe patients’ survival and functional (physical and cognitive) outcomes at six months following an ICU admission of at least three days during which they received life-sustaining therapy in the form of mechanical ventilation for > 48 hours and/or vasopressors for > 24 hours within their first six days in the ICU.
Of 473 patients who met inclusion criteria, 303 ultimately consented to participate. Median age was 62 years (interquartile range, 53-71), 57.1% were male, and 37% were non-white. Prior to their ICU stay, 94.1% of patients resided at home, 28.4% were employed, and 68.0% demonstrated normal baseline function, defined as living at home with no self-reported deficits in cognition or abilities to ambulate up 10 stairs and toilet independently. ICU admission diagnoses were most common for respiratory failure (27.4%), sepsis (21.8%), and non-emergency surgery (17.8%).
Of the 303 enrolled patients, 72 (23.8%) died in the hospital, 21 (6.9%) were discharged to inpatient hospice, and 58 (17.5%) died between hospital discharge and the six-month follow-up. Of the surviving 173 patients at six months, 82.8% had returned to their original residence, 81.9% could toilet independently, 71.3% could ambulate 10 stairs independently, and 62.4% reportedly exhibited normal cognition. Surgical ICU patients experienced better survival and morbidity outcomes compared to medical ICU patients. Of the original 303 enrolled patients, 293 had complete data for six-month physical and cognitive outcomes and baseline characteristics, and were included in an analysis to identify predictors of return to baseline function. Of these, 91 (31.1%) returned to baseline at six months. Normal function prior to ICU admission was not associated significantly with increased likelihood to return to baseline. Independent predictors of not returning to baseline function included older age, being a medical (as opposed to a surgical) patient, non-white race, higher APACHE III score, hospitalization in the prior year, and a history of cancer, liver disease, neurologic condition, or any type of transplant.
This is a comprehensive cohort study that uncovered several important findings. First, six-month mortality among patients with ICU stays requiring life-sustaining therapy is quite high at 43%. Although hospitalization in the prior year was an independent predictor of poor return to baseline function in the multivariable model, it is notable that most patients (94.1%) resided at home, and 68% reported normal baseline function prior to their ICU hospitalization. Thus, an ICU hospitalization requiring life-sustaining therapy is a defining moment. A similar pattern has been observed in multiple studies focused on outcomes after hospitalization for severe sepsis.1,2
Second, the multivariable model presented is unique in its use of return to baseline status as an outcome that is important in ICU survivorship. Third, although six-month mortality is high, most patients who survive to six months are at home and functioning normally, albeit with cognitive impairments outnumbering physical ones. These findings are intriguing when viewed in the context of studies that have found that among patients on prolonged mechanical ventilation, only 9% are at home and independently functioning at the one-year mark.3 To the extent that functional status is an important component of quality of life for patients, data from the Detsky et al study are informative, although the results do not mitigate the complexity of real-time decisions in the ICU, especially when the decision involves whether to continue aggressive care (and possibly tracheostomy and G-tube placement) vs. pursue comfort care/hospice. For patients requiring life-sustaining ICU support, even briefly as defined by this study, these data suggest that mortality is high, but if they survive, the majority can return home and achieve some degree of normal function by six months. However, based on data from other studies, if patients continue to remain dependent on mechanical ventilation for a longer period, at some point a threshold is crossed such that their chances of functional independence decline drastically. It is interesting to note that surrogate ratings overall were more pessimistic than reports from patients in the study. Although independent risk factors for return to baseline are presented, they have yet to be validated as part of an accurate scoring system for predicting the outcome of return to baseline. Currently, data from this study are probably most helpful as part of patient and/or surrogate discussions regarding what to expect in terms of recovery, even after brief, but intense, ICU stays.
- Prescott HC, Langa KM, Liu V, et al. Increased 1-year healthcare use in survivors of severe sepsis. Am J Respir Crit Care Med 2014;190:62-69.
- Liu V, Lei X, Prescott HC, et al. Hospital readmission and healthcare utilization following sepsis in community settings. J Hosp Med 2014;9:502-507.
- Unroe M, Kahn JM, Carson SS, et al. One-year trajectories of care and resource utilization for recipients of prolonged mechanical ventilation. Ann Intern Med 2010;153:167-175.