Long-term outcomes following critical illness in children

Pearls

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Development of specialized pediatric intensive care has contributed to substantially reduced mortality for critically ill children.
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Research has identified physical, cognitive, health-related quality of life, and mental health domains as areas of persistent impairment among children surviving critical illness.
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Postintensive care syndrome is the development of new or worsening impairments in physical, cognitive, or mental health arising after critical illness and persisting beyond acute care hospitalization.
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Morbidity measures are increasingly being incorporated as primary and secondary endpoints in pediatric critical care interventional trials.
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There is an urgent need for additional research to better characterize postintensive care morbidity and its risk factors, with the goal of minimizing adverse sequelae associated with critical illness.

Mortality reduction represented the first frontier for critical care medicine and historically has been the most commonly used outcome measure in interventional trials enrolling critically ill patients. Fortunately, as the subspecialty of pediatric critical care has matured, overall mortality rates for critically ill children have substantially declined to current rates of 2% to 3% of all pediatric intensive care unit (PICU) admissions.

Many children surviving critical illness, however, struggle to regain their prehospitalization health status, experiencing persistent deficits in functional status, health-related quality of life (HRQL), cognitive and school performance, and mental health. They also experience high rates of hospital readmission, ongoing healthcare use, and late mortality. Patients’ families also experience emotional, financial, and social strains, which, in turn, can make it more difficult for them to support the recovery of their children. As increasing numbers of children are now surviving severe illnesses, pediatric critical care may be exchanging mortality for enduring morbidity. ^, The next frontier for pediatric critical care medicine is to characterize the scope of long-term postdischarge morbidity, better identify the antecedents of morbidity and the survivors most at risk, and define potential targets for intervention to help optimize recovery from pediatric critical illness.

Post–intensive care syndrome

Children surviving critical illness and intensive care are vulnerable to ongoing problems in all domains of life ( Table 21.1 ). Physical, emotional, cognitive, social, and family functioning may all be affected to the detriment of overall HRQL and a family’s socioeconomic status. In adult survivors of critical illness, an increasing appreciation for new morbidity persisting after discharge in multiple domains led to the development of the concept of post–intensive care syndrome (PICS) and post–intensive care syndrome family (PICS-F). More recently, this concept has been applied to children as pediatric PICS (PICS-p), with the notable difference from the PICS concept in adults being that childhood development and family are integral to a child’s recovery from illness ( Fig. 21.1 ). ^,

TABLE 21.1

Domains of Health Outcomes and Examples of Morbidity Following Pediatric ICU Discharge

Domain	Morbidity examples
Health-related quality of life	Unable to participate in activities Difficulty with self-care Low energy level Worrying or feeling sad Difficulty getting along with peers Memory or attention deficits Difficulty with schoolwork or missing school
Functional/physical	Motor dysfunction Impaired level of consciousness Feeding or respiratory support Hearing or vision deficits Neuromuscular weakness ICU-associated polyneuropathy Pain
Cognitive	Executive function Processing speed Memory Attention Academic performance
Mental health	Anxiety Depression Acute stress disorder Posttraumatic stress disorder Disturbed sleep patterns and nightmares
Family	Family stress Mental health of family members Relationship conflict and divorce Disruption of siblings’ routines
Social	Difficulty interacting with peers Missed school Family isolation
Economic	Costs of acute care Loss of income due to missed work or job loss Ongoing care needs

ICU, Intensive care unit.

Health-related quality of life

HRQL is increasingly being used as a comprehensive measure of health outcomes and has been identified by both families and healthcare professionals as the most important outcome to assess among PICU survivors. Quality of life is defined as an individual’s perception of his or her position in life in relation to the individual’s goals, expectations, standards, and concerns. ^, HRQL is defined as quality of life in which a dimension of personal judgment over one’s health and disease is added ^, ; it encompasses the impact of health status on physical, mental, emotional, and social functioning. ^, HRQL in children is influenced by factors such as the ability to participate in peer groups, keep up with developmentally appropriate activities, and succeed in school. It provides a broad view of child health, encompassing aspects of perceived health, health behavior, and well-being.

Baseline HRQL is determined by genetics ; parent, family, and home characteristics ; and chronic, comorbid conditions ( Fig. 21.2 ). ^, In assessing HRQL among a generalized sample of US children, lower HRQL was noted for children in lower socioeconomic status groups, those with healthcare access barriers, adolescents compared with children, and individuals with chronic medical conditions. These same variables likely impact HRQL recovery following critical illness in addition to the effects of acute illness and associated treatments. Individual characteristics influencing HRQL include personality traits, chronic comorbid conditions, and genetics; environmental characteristics include parental stress, family dynamics, and home demographics; and clinical variables specific to critical illness include the intensity and duration of organ system dysfunction and exposure to ICU therapies.

HRQL instruments should provide reliable and valid measures that can quickly and easily be used to quantify morbidity or disability after a child’s critical illness or injury. These tools must be multidimensional and include physical, mental, and social health domains. Preferably, HRQL questionnaires should be completed by the critically ill children if they are 6 to 8 years of age and older. Parent-proxy reporting is often necessary in a critically ill population, however, and is also a valid approach. eTable 21.2 provides a list of HRQL measures that have been used in pediatric critical care studies and summarizes important psychometric properties of these tools. The most comprehensive instruments for assessing HRQL that are currently available are the PedsQL 4.0 Generic Core Scales, KIDSCREEN-27, the 28-item Child Health Questionnaire parent form (CHQ-PF28), and KINDL. These tools are offered as both self-reports and proxy reports, cover a wide age range of children, are brief with a low response burden, are multidimensional, have been shown to have internal consistency and test-retest reliability, demonstrate sensitivity to change over time, and have content and construct validity.

eTABLE 21.2

Health-Related Quality of Life (HRQL) Assessment Tools

Instrument	Name/Origin	Age (y)	No. Items	No. Domains	Time (min)	Report	Reliability	Validity	Sensitivity to Change	Physical	Emotional	Social/Behavioral	School
CHIP-AE	Child Health & Illness Profile—Adolescent Edition (US)	11–17	183	6	45	Self	ICC Test-retest	Content Construct Criterion		x	x	x	x
CHIP-CE	Child Health & Illness Profile—Child Edition (US)	6–11	76 (proxy) 45 (self)	5	20	Proxy Self	ICC Test-retest	Content Construct Criterion		x	x	x	x
CHQ-CF87	Child Health Questionnaire—Child Form (US)	10–18	87	13	20	Proxy Self (10+)	ICC Test-retest	Content Construct Criterion	x	x	x	x	x
CHQ-PF50	Child Health Questionnaire—Parent Form (US)	5–18	50	13	20	Proxy Self (5+)	ICC Test-retest	Content Construct Criterion	x	x	x	x	x
CHQ-PF28	Child Health Questionnaire—Parent Form (US)	5–18	28	13	5–10	Proxy Self (5+)	ICC Test-retest	Content Construct Criterion	x	x	x	x	x
COOP	Dartmouth COOP Charts (US)	8–18	6	6		Self	Test-retest	Construct		x	x	x	x
DISABKIDS	DISABKIDS (Europe)	4–16	37	6	10	Proxy Self	ICC Test-retest	Content Construct		x	x	x
EQ–5D	EuroQOL (Europe)	5–18	5			Proxy Self	Test-retest	Construct		x	x		x
FIM/WEEFIM	Functional Independence Measure	0–18	18			Proxy	Test-retest	Content Construct		x		x
FS IIR	Functional Status II Revised (US)	0–16	14	8	10	Proxy	ICC	Content Construct		x	x	x
HUI 3	Health Utilities Index 3 (Canada)	2–18	45	8	<5	Proxy Self	Test-retest	Construct		x	x
ITQOL	Infant & Toddler QOL Questionnaire	2 mo–5 y	103	10		Proxy	ICC Test-retest	Content Construct Criterion		x	x	x
KIDSCR-52	Kidscreen (International)	8–18	52	10	15–20	Proxy Self	ICC	Content Construct	x	x	x	x	x
KIDSCR-27	Kidscreen (International)	8–18	27	5	10–15	Proxy Self	ICC Test-retest	Content Construct	x	x	x	x	x
KINDL	Kidscreen (Germany)	8–16 4–7	24 12	6 4	5–10	Proxy Self	ICC	Content Construct	x	x	x	x	x
PEDI	Pediatric Evaluation & Disability Inventory	0–8	237			Proxy	ICC Test-retest	Content Construct Criterion		x		x	x
PedsQL 4.0	Pediatric Quality of Life Inventory (US)	2–18	23	4	5–10	Proxy Self (5+)	ICC Test-retest	Content Construct Predictive	x	x	x	x	x
QWD	Quality of Well-Being Scale	4–18	29			Proxy Self (11+)	Test-retest	Construct		x		x
TACQOL	TNO-AZL Child QOL (Netherlands)	6–15	108	7	10	Proxy Self (8+)	ICC	Content Construct		x	x	x
TA PQOL	TNO-AZL Parent QOL (Netherlands)	1–5	43	4	10	Proxy				x	x	x
YQOL-R	Youth Quality of Life Instrument—Research Version (US)	11–18	56	4	10–15	Self	ICC Test-retest			x	x	x
VSP-A	Vecu et Sante Percue de l’Adolescent (France)	11–17	37	9		Self	ICC Test-retest	Content Construct		x	x	x	x