Objectives: There is growing evidence for increased levels of pain and reduced health-related quality of life in survivors of critical illness. Recent studies showed marked small nerve fiber pathology in critically ill patients, which may contribute to chronic pain states and reduced physical recovery after ICU discharge. Primary objective of this study was the comparison of somatosensory functions between survivors of critical illness 6 months after ICU discharge and controls. In post hoc analyses, we aimed to identify associations between small fiber deficits, pain, health-related quality of life, and clinical data.
Design: Cross-sectional study.
Setting: Study in critical illness survivors.
Patients: Critical illness survivors (n = 84) and controls (n = 44).
Interventions: None.
Measurements and main results: Somatosensory functions were assessed with validated quantitative sensory testing. Pain and pain-related disability were assessed with the chronic pain grade questionnaire. Health-related quality of life was assessed by means of the Short Form-36. Compared with controls, former patients showed significantly increased thermal detection thresholds and more abnormal values in thermal testing, indicating reduced small fiber functioning. In addition, compared to patients without significant small fiber deficits (n = 46, 54.8%), patients with significant small fiber deficits (n = 38, 45.2%) reported higher average pain intensity, pain-related disability, and reduced physical health-related quality of life in the SF-36.
Conclusions: A large portion of former critically ill patients show small fiber deficits which seem to be associated with increased pain and reduced physical health-related quality of life. Screening of somatosensory functions in the (post-) acute setting could possibly help to identify patients at risk of long-term impairments.