Comprehensive Assessment and Management of the Critically Ill

Caring for an older adult who is experiencing a serious or life-threatening illness often poses significant challenges for critical care nurses. Although older adults are an extremely heterogeneous group, they share some age-related characteristics that leave them susceptible to a variety of geriatric syndromes and diseases. This vulnerability may influence both their ICU utilization rates and outcomes. Critical care nurses caring for this population must not only recognize the importance of performing ongoing, comprehensive physical, functional, and psychosocial assessments tailored to the older ICU patient, but also must be able to identify and implement evidence-based interventions designed to improve the care of this extremely vulnerable population.


A.  Definition

A critically ill older adult is a person, aged 65 years or older, who is currently experiencing, or at risk for, some form of physiological instability or alteration warranting urgent or emergent, advanced, nursing/medical interventions and monitoring.

B.  Etiology/epidemiology

  1. More than one half (55.8%) of all ICU days are incurred by patients older than 65 years (Angus et al., 2006).
  2. Older adults are living longer, are more racially and ethnically diverse, often have multiple chronic conditions, and more than one quarter report difficulty performing one or more ADL. These factors may affect both the course and outcome of critical illness.
  3. Once hospitalized for a life-threatening illness, older adults often:
    • Experience high ICU, hospital, and long-term crude mortality rates and are at risk for deterioration in functional ability and postdischarge institutional care (Balas et al., 2009, 2011; Brummel et al., 2014; de Rooij et al., 2008; Esteban et al., 2004; Ford et al., 2007; Hennessy et al., 2005; Hopkins & Jackson, 2006; Kaarlola et al., 2006; Pandharipande et al., 2013; Wunsch et al., 2010)
    • Older age is also a factor that may lead to:
      • Physician bias in refusing ICU admission (Joynt et al., 2001; Mick & Ackerman, 2004)
      • The decision to withhold MV, surgery, or dialysis (Hamel et al., 1999)
      • An increased likelihood of an established resuscitation directive (Hakim et al., 1996)
    • Most critically ill older adults:
      • Demonstrate resiliency
      • Report being satisfied with their postdischarge QOL
      • Would reaccept ICU care and MV if needed (Guentner et al., 2006; Hennessy et al., 2005; Kleinpell & Ferrans, 2002)
    • Chronological age alone is not an acceptable, or accurate, predictor of poor outcomes after critical illness (D. Elliott et al., 2014; Milbrandt et al., 2010; Nagappan & Parkin, 2003).
    • Factors that may influence an older adult’s ability to survive a catastrophic illness include (de Rooij et al., 2005; Ford et al., 2007; Marik, 2006; Mick & Ackerman, 2004; Wunsch et al., 2010):
      • Severity of illness
      • Nature and extent of comorbidities
      • Diagnosis, reason for/duration of mechanical ventilation
      • Complications
      • Others
        • Prehospitalization functional ability
        • Vasoactive drug use
        • Preexisting cognitive impairment
        • Senescence
        • Ageism
        • Decreased social support
        • The critical care environment
        • Patient preference
        • Dementia is a common development in older adults after admission to ICU for critical illness.
      • Newly developed (incident) dementia is present in 12% to 18% of patients at 1 year to 8 years post critical illness (Brummel et al., 2014; Ehlenbach et al., 2010; Guerra et al., 2012; Herridge et al., 2011).
      • Prevalent (unknown preillness status) dementia is reported in 15% of patients post discharge, and in 10% of patients at 1 year follow-up (Sacanella et al., 2011).
      • Newly acquired mild or moderate cognitive impairment is reported in 56% of patients at 4 years post critical illness (de Rooji et al., 2008).


A.  On admission to the ICU, the nurse should ask relatives or other caregivers for baseline information about the older adults’

  1. Memory, executive function (e.g., fine motor coordination, planning, organization of information, etc.), and overall cognitive ability (Kane et al., 2004)
    • Behavior on a typical day, how the patient interacts with others; his or her responsiveness to stimuli, how able he or she is to communicate (reading level, writing, and speech); and his or her memory, orientation, and perceptual patterns before the illness (Milisen & DeGeest, 2001).
  2. Medication history to assess for potential withdrawal syndromes and adverse drug events (Broyles, Colbert, Tate, Swigart, & Happ, 2008; Bunditz et al., 2006).
  3. Preadmission functional ability, frailty, and nutritional status—limited preadmission functional ability, frailty, and poor nutritional status are associated with many negative outcomes for critically ill older adults (Fronczek et al., 2018; Hamidi et al., 2019). Therefore, the nurse should assess the following:
    • Did the elder suffer any limitations in the ability to perform his or her ADL preadmission? If so, what were these limitations?
    • Does the elder use any assistive devices to perform ADL? If so, what type?
    • Where did the patient live before admission? Did he or she live alone or with others? What was the elder’s physical environment like (i.e., house, apartment, stairs, multiple levels, etc.)?
    • What was the older adult’s nutritional status like before admission? Does he or she have enough money to buy food? Does he or she need assistance with making meals/obtaining food? Does he or she have any particular food restrictions/preferences? Was he or she using supplements/vitamins on a regular basis? Does he or she have any signs of malnutrition, including recent weight loss/gain, muscle wasting, hair loss, skin breakdown?
  4. Psychosocial factors—Critical illness can render older adults unable to communicate effectively with the healthcare team, often related to physiological instability, technology that leaves them voiceless, and sedative and narcotic use (Happ, 2000, 2001). Family members are therefore often a crucial source for obtaining important preadmission information.
    • What is the elder’s past medical, surgical, and psychiatric history? How did the elder communicate prior to the critical illness? What medication was the older adult taking before coming to the ICU? Does the elder use illicit drugs, tobacco, or alcohol regularly? Does he or she have a history of falls, physical abuse, or confusion?
    • What is the older adult’s marital status? Who is the patient’s significant other? Will this person be the one responsible for making decisions for the elder if he or she is unable to do so? Does the elder have an advance directive for healthcare? Is the elder a primary caregiver to an aging spouse, child, grandchild, or other person?
    • How would the elder describe his or her ethnicity? Does he or she practice a particular religion or have spiritual needs that should be addressed? What was his or her QOL like before becoming ill?

B.  During ICU stay—There are many anatomic/physiological changes that occur with aging (see Table 35.1). The interaction of these changes with the acute pathology of a critical illness, comorbidities, and the ICU environment not only leads to atypical presentation of some of the most commonly encountered ICU diagnoses, but may also elevate the older adults’ risk for complications. The older adult must be systematically assessed for the following:

  1. ICU/Environmental factors—Deconditioning, poor oral hygiene, sleep deprivation, pain, immobility, nutritional status, MV, hemodynamic monitoring devices, polypharmacy, high-risk medications (e.g., narcotics, sedatives, hypnotics, nephrotoxins, vasopressors), lack of assistive devices (e.g., glasses, hearing aids, dentures), noise, tubes that bypass the oropharyngeal airway, poorly regulated glucose control, Foley catheter use, stress, invasive procedures, shear/friction, intravenous catheters
  2. Atypical presentations of illness are commonly seen in older adults experiencing the following:
    • Myocardial infarction
    • Acute abdomen
    • Systemic infection
    • Hypoxia


A.  Preadmission: Based on the individual’s preadmission assessment findings, the nurse should consider:

  1. Obtaining appropriate consults (i.e., dietitian, physical/occupational/speech therapist)
  2. Implementing safety precautions
  3. Using pressure-relieving devices
  4. Organizing family meetings
  5. Providing the older adult with a consistent primary nurse
  6. Screening for risk factors placing the patient at increased likelihood of developing PICS
    • Preexisting risk factors: Senescence, comorbid illnesses, disease pathology
    • ICU syndromes/conditions: Pain, delirium, and oversedation

B.  During ICU admission, the nurse should attempt to:

  1. Continue to screen for ICU conditions using appropriate tools such as the RASS, CAM-ICU, and Intensive Care Delirium Screening Checklist (ICDSC; Bergeron, Dubois, Dumont, Dial, & Skrobik, 2001; Ely et al., 2001a, 2001b; Riker, Picard, & Frasier, 1999; Sessler et al., 2002).
  2. Prevent development of ICU conditions by implementing ABCDEF bundle (see Table 35.2).
    • Assess, prevent, and manage pain using verified pain scale such as Critical Care Pain Observation Tool (CPOT) or Behavioral Pain Scale (BPS; Gélinas, Fillion, Puntillo, Viens, & Fortier, 2006; Payen et al., 2001).
    • Coordinate SAT and SBT to assess need for sedation and ventilation concurrently.
    • Ensure choices of analgesic and sedative medications are appropriate for the patient condition.
    • Assess, prevent, and manage delirium.
    • Encourage early mobility and exercise.
    • Increase family engagement and empowerment.
  3. Foster patient communication strategies
    • Consider use of algorithm-guided assessment and communication tool selection (Happ et al., 2014)
    • Consider consulting speech therapist to facilitate communication (Happ et al., 2010; Altschuler & Happ, 2019)
  4. Consider other appropriate interventions (see Box 35.1)


A.  Patient

  1. Preadmission functional ability will be maintained/optimized.
  2. ICU syndromes such as pain, anxiety, immobility, and delirium will be minimized.
  3. Communication between the patient, family, and the healthcare team will be improved.

B.  Provider

  1. Employ consistent and accurate documentation of assessment relevant to the older ICU patient.
  2. Provide consistent, accurate, and timely care in response to deviations identified through ongoing monitoring and assessment of the older ICU patient.
  3. Provide patient/caregiver with information and teaching related to his or her illness as well as news of transfer of care and/or discharge.

C.  Institution—include QA/QI

  1. Evaluate staff competence in the assessment of older critically ill patients.
  2. Use unit-specific, hospital-specific, and national standards of care to evaluate existing practice.
  3. Identify areas for improvement, and work collaboratively across disciplines to develop strategies for improving critical care to older adults.


Barr, J., Fraser, G. L., Puntillo, K., Ely, E. W., Gélinas, C., Dasta, J. F., … Jaeschke, R.; American College of Critical Care Medicine. (2013). Clinical practice guidelines for the management of pain, agitation, and delirium in adult patients in the intensive care unit. Critical Care Medicine, 41(1), 263–306. doi:10.1097/CCM.0b013e3182783b72. Evidence Level VI.

Devlin, J. W., Skrobik, Y., Gélinas, C., Needham, D. M., Slooter, A. J., Pandharipande, P. P., … Alhazzani, W. (2018). Clinical practice guidelines for the prevention and management of pain, agitation/sedation, delirium, immobility, and sleep disruption in adult patients in the intensive care unit. Critical Care Medicine, 46(9), e826–e873. doi:10.1097/CCM.0000000000003299


ADL            Activities of daily living

ICU             Intensive care unit

MV              Mechanical ventilation

PICS            Post-intensive care syndrome

QA              Quality assurance

QI                Quality improvement

QOL            Quality of life

SAT             Spontaneous awakening trial

SBT             Spontaneous breathing trial


Boltz PhD, RN, GNP-BC, FGSA, FAAN, M., Capezuti PhD, RN, FAAN, E., Zwicker DrNP, APRN, BC, D., & Fulmer PhD, RN, FAAN, T. T. (2020). Evidence-Based Geriatric Nursing Protocols for Best Practice (6th ed.). Springer Publishing. Retrieved November 4, 2020, from

Chapter 35:  Balas, M., Cordell, L., Donahue, P., & Happ, M. (2021) Comprehensive Assessment and Management of the Critically Ill Older Adult.  In M. Boltz, E. Capezuti, D. Zwicker & T. Fulmer (eds.).  Evidence-Based Geriatric Nursing Protocols for Best Practice (6th ed. pp 633-657).   New York: Springer.


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