Quality of life following prolonged critical illness: A mixed methods study

Abstract

Survival following critical illness is associated with a significant burden of physical and psychosocial morbidity and recovery is often protracted and/or incomplete. Recovery has been measured using, almost exclusively, generic health-related quality of life (HRQoL) questionnaires. There is, however, an inexorable lack of consensus on the conceptual definition of HRQoL, and existing measures have tended to reflect overtly biomedical concerns such as morbidity and impairment at population level. Limited empirical or theoretical work has examined the extent to which widely used measures reflect the individual’s concerns, “health”-related and otherwise. The primary aims of this PhD are to examine HRQoL among a rarely studied sub group of the critically ill patient population: survivors of prolonged critical illness, and to explore the extent to which professionally endorsed measures capture their experiences of and perspectives on the recovery process. The implications of “patient-centredness” are both diverse and far-reaching in terms of policy, practice and critical care outcomes research, and are discussed throughout. A review of the literature among a well studied sub group of the patient population (survivors of Adult Respiratory Distress Syndrome) identified the widespread use of generic and ancillary measures which were invariably developed for use among other patient populations. This approach was seen to offer limited insight to the putative relationship between critical illness-related morbidity and HRQoL. Reflecting existing professional recommendations and practice, the Short Form 36 (SF-36) and the EuroQoL were administered by post to 20 survivors of prolonged critical illness at up to 6 months following ICU discharge. Each subsequently participated in a semi-structured interview, the purpose of which was to explore experiences and perceptions of ongoing morbidity within the contexts of the critical illness “journey” and, importantly, everyday life. A small number (n=5) participated in cognitive interview in order to explore both the everyday logistics of questionnaire completion and the often startling inconsistencies between verbal and questionnaire response. Analysis here revealed the unexpectedly diverse and normally hidden processes through which survivors interpreted and responded to standardised questionnaire items, challenging traditional (i.e. psychometric) notions of validity. Data from the semi-structured interviews were “mapped” onto the dimensions of the SF-36, revealing the highly contextualised and complex inter-relatedness of biomedically defined and ostensibly discrete aspects of experience. Morbidity was conceptualised by survivors in terms of the adaptive and interpretive processes adopted in everyday life (as opposed to a source of loss) and was generally under-reported in questionnaire form. An alternative explanatory framework for HRQoL was subsequently developed. Data were also analysed with reference to the “biographical narrative” of critical illness, a strategy which revealed the significance of survivors’ own stock of “life experience” (health-related and otherwise) in these interpretive and adaptive processes. The unexpectedly phlegmatic nature of survivors’ accounts directed attention to the narrative form, lending credibility to survivors’ claims that “things weren’t that bad”; accounts of seemingly intolerable morbidity were perceived, for example, as “a lucky escape”. This data also revealed, however, the influence of shortfalls in the processes and delivery of acute hospital rehabilitation upon the efficacy of these interpretive and adaptive processes. Mixed methods approaches to HRQoL, in summary, offer significant insights into survivors’ conceptualisations of morbidity, recovery, quality of life and the complex inter-relationships therein. Attention to the processes of adaptation also offers significant potential for the development of patient-centred measures of outcome and the expedition of the recovery process in ways which are most meaningful to survivors.