Time-limited trials in the ICU: a mixed-methods sequential explanatory study of intensivists at two academic centres

OBJECTIVE: To understand intensivist perceptions of the appropriateness of time-limited trials (TLTs)—a strategy to align life-sustaining care with patient goals and values in the midst of clinical uncertainty. DESIGN: We conducted a mixed-methods sequential explanatory study of intensive care unit (ICU) intensivists regarding appropriateness of utilising TLTs in three vignettes centred on invasive mechanical ventilation (IMV); continuous renal replacement therapy (CRRT); and heated high-flow nasal cannula (HHFNC). Semistructured interviews were conducted using the Tailored Implementation of Chronic Diseases framework. Data were analysed using thematic and matrix analysis. SETTING: Two academic medical centres in the USA participated in the randomised surveys and one centre participated in the semistructured interviews. PARTICIPANTS: Pulmonary and critical care intensivists and fellows. PRIMARY AND SECONDARY OUTCOMES: To understand intensivists perceptions of the appropriateness in using TLTs. RESULTS: Of 115 physicians surveyed, 71 initiated the survey and 44 completed the entire survey with a response rate of 38% (N=44/115) and a completion rate of 62% (N=44/71). While 35% (N=23/66) of intensivists had never heard of a TLT, of the intensivists who had heard of a TLT, 77% (N=33/43) had participated in one. In response to the vignettes, appropriateness of using a TLT varied (IMV: 74% (N=46/62); CRRT 78% (N=49/63); HHFNC 92% (N=56/61) as did the durations of the TLT. Semistructured interviews with 11 intensivists revealed having clarity about patient goals and clinical endpoints facilitated successful TLTs while lack of an evidenced-based framework was a barrier. CONCLUSION: More than half of the physicians who responded had conducted or participated in a TLT. To increase the use of TLTs in the ICU, clinicians desire a more robust, evidence-based framework on how to conduct TLTs.