Page 131 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 14: Chronic Critical Illness 97

CHAPTER Chronic Critical Illness TABLE 14-1 Phenotype of Chronic Critical Illness
14 Shannon S. Carson Prolonged ventilatory failure and ventilator dependence
Residual hypoxemia and decreased lung compliance from ARDS
Respiratory muscle weakness
Hemodynamic instability
Residual or recurrent sepsis
Orthostatic hypotension
KEY POINTS Arrhythmias
• Between 5% and 10% of patients admitted to adult ICUs become Right and left ventricular dysfunction
chronically critically ill. The burden of chronic critical illness is Renal insufficiency or failure
anticipated to increase dramatically in the next decade as the popula- Malnutrition
tion ages and more patients survive the acute phase of critical illness. Hyperglycemia and insulin resistance
Anasarca
• Advanced age and multiple organ failure due to severe sepsis and Muscle atrophy
multiple trauma are the most significant risk factors for chronic Skin breakdown
critical illness, especially when complicated by comorbidities and Delirium or coma
nosocomial complications. Anxiety and depression
• Chronically critically ill patients have distinct physiology com-
pared with more acutely ill patients, including suppressed levels
of anterior pituitary hormones, severe depletion of protein stores
with muscle wasting, and relative immune compromise. CCI patients have a phenotype that is recognizable to critical care
1
• Important principles of patient management include prevention clinicians of any discipline (Table 14-1). Patients are usually extremely
of infection, protein repletion, limitation of sedating medications, weak and dependent on mechanical ventilation. Their physical appear-
aggressive physical therapy, and careful attention to treating pain ance is altered by muscle atrophy and generalized edema, and a trache-
and depression. ostomy has been placed or is being contemplated. Sixty-three percent
2
• Liberation from mechanical ventilation is usually achieved with are delirious or comatose, and those that are alert report a wide range
work-rest cycles that are guided by frequent assessments of readi- of symptoms such as pain, dyspnea, thirst, or anxiety, mostly at severe
3
ness for weaning and careful monitoring to avoid fatigue. Weaning levels. They are often cycling through recurring infections, multiple
protocols that include daily periods of unassisted breathing are antibiotics, and are being colonized by multidrug resistant organisms.
more efficient than protocols that are based on gradual decreases Their families are distressed, frustrated, and exhausted. Finally, their
in pressure support ventilation. physicians and nurses are equally frustrated and often are challenged to
• One-year survival for chronically critically ill patients is between maintain enthusiasm for their care.
Despite having a recognizable phenotype, a common definition for
40% and 50% in most cohorts. CCI is more elusive. For the purposes of epidemiologic studies or clinical
• Chronically critically ill patients experience a median of four trials, patients are identified by a certain number of days of mechanical
transfers of care after acute hospital discharge, and 74% of days ventilation or ICU care, by presence of a tracheostomy for prolonged
alive during the subsequent year are spent in institutionalized care ventilation, or by transfer to a ventilator rehabilitation unit. The actual
4
or receiving professional care at home. After 1 year, only 10% of number of days of ventilation or ICU stay that is considered to meet a
patients are alive and functionally independent at home. threshold of prolonged has varied from 2 to 29 days depending on an
• Costs of care for chronically critically ill patients are extreme investigator’s intuitive sense of what is exceptional or by restrictions
during hospitalization and after discharge. Cost savings can be of administrative databases. In 2005, a consensus conference repre-
5-7
achieved by managing hemodynamically stable patients in dedi- senting physicians, respiratory therapists, nurses, and long-term care
cated wards or facilities outside of the acute ICU setting with lower hospitals recommended a standard definition for prolonged mechanical
nurse-to-patient ratios. ventilation (PMV) of greater than or equal to 21 consecutive days of
• There is often significant discordance in understanding of long- mechanical ventilation for ≥6 hours per day. However, more recent
8
term outcomes between surrogate decision makers and clinicians. clinical trials involving PMV patients are enrolling patients after 10 or
The ProVent Score, a validated clinical prediction rule for long- 14 days of mechanical ventilation in order to intervene earlier along the
1
term mortality in chronically critically ill patients, can inform continuum from acute to chronic critical illness. Placement of a trache-
discussions of prognosis in shared decision making. ostomy for prolonged ventilation is considered by many to be a good
definition of CCI because clinicians have determined that the patient
is unlikely to die or be liberated from mechanical ventilation in a short
period. However, there is wide variation between centers as to how early
9
Advances in medical management and technology have greatly enhanced and even if to place a tracheostomy in specific conditions. When using
10
patients’ ability to survive critical illness and injury. For most critically administrative data such as Medicare datasets that do not include venti-
ill patients, the clinical course is typified by liberation from organ sup- lator days, the most reliable approach is to identify patients who have an
port systems such as vasoactive drugs and mechanical ventilation after ICU length of stay of ≥21 days and have been assigned DRG 541 or 542
reversal of the acute process, followed by a short period of observation (tracheostomy for a condition other than head, neck or face disease) or
before transfer from the ICU to a medical/surgical ward or an interme- ICD-9 code 96.72 (mechanical ventilation >96 hours). 7
diate care unit. For a significant number of patients, however, this timely
transition to a more stable condition does not occur, and they remain INCIDENCE
dependent on life-support systems or other ICU services for prolonged
periods. These patients often are referred to as the chronically critically ill Depending on the definition, between 5% and 10% of patients admitted
(CCI). As larger proportions of aging patients are surviving episodes of to adult ICUs become chronically critically ill. 11,12 Patients with DRG 541
severe sepsis, the acute respiratory distress syndrome (ARDS), multiple or 542 increased from 86,911 in 2000 to 116,491 in 2010, an increase
trauma, or acute on chronic respiratory failure, CCI patients are becom- of 34%. Total hospitalizations only increased by 7% during that period
ing a significant component of the practice of critical care medicine. (AHRQ National Inpatient Sample, 2010. http://hcupnet.ahrq.gov)

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