Mutual relationship between anxiety and pain in the intensive care unit and its effect on medications

Purpose: Little is known about the relationship between anxiety and pain in intensive care unit (ICU) patients despite its importance. The aims of the present study are to examine the correlation between pain and anxiety during ICU care and to investigate its effects on the dose of opioids and anxiolytics administered. Methods: The study subjects were awake critically ill patients admitted to an ICU over a 2-month period. Trained psychiatrists evaluated the nondelirious, noncomatose patients daily for anxiety and pain using the Numeric Rating Scale for Pain (NRS-Pain), Faces Anxiety Scale (FAS), and Hamilton Anxiety Rating Scale. Results: Daily alterations of anxiety and pain were significantly correlated with one another among 123 patients. Both the FAS and the Hamilton Anxiety Rating Scale were positively correlated with the NRS-Pain (P < .001 for both). The NRS-Pain score (P = .016) and the FAS score (P = .007) both significantly correlated with the dose of anxiolytics. The dose of opioids was unaffected by the severity of pain or anxiety. Conclusions: Pain and anxiety among critically ill patients in the ICU were closely correlated. Pain and anxiety influenced the dose of anxiolytics administered. Therefore, a precise evaluation and comprehensive approach to the management of pain and anxiety are important for treating ICU patients.