Back to Journals » Neuropsychiatric Disease and Treatment » Volume 12

Incidence, risk factors, and phenomenological characteristics of postoperative delirium in patients receiving intravenous patient-controlled analgesia: a prospective cohort study

Authors Lin YT, Lan KM, Wang LK, Chu CC, Wu SZ, Chang CY, Chen JY

Received 15 August 2016

Accepted for publication 7 November 2016

Published 13 December 2016 Volume 2016:12 Pages 3205—3212


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 2

Editor who approved publication: Professor Wai Kwong Tang

Yao Tsung Lin,1 Kuo Mao Lan,1 Li-Kai Wang,1 Chin-Chen Chu,1 Su-Zhen Wu,1 Chia-Yu Chang,2 Jen-Yin Chen1,3

1Department of Anesthesiology, 2Department of Neurology, Chi Mei Medical Center, 3Department of the Senior Citizen Service Management, Chia Nan University of Pharmacy and Science, Tainan, Taiwan

Background: Intravenous patient-controlled analgesia (IVPCA) is a common method of relieving pain which is a risk factor of postoperative delirium (POD). However, research concerning POD in IVPCA patients is limited.
Objective: We aimed to determine the incidence, risk factors, and phenomenological characteristics of POD in patients receiving IVPCA.
Methods: A prospective, cohort study was conducted in post-general anesthesia IVPCA patients aged ≥60 years. POD was measured by the Nursing Delirium Screening Scale (NuDESC; 0–10). Delirium, pain severity at rest and/or on movement, and side effects of IVPCA during 3 postoperative days were examined twice-daily by the acute pain service team. Pain severity is measured by an 11-point verbal numerical rating scale (11-point VNRS) (0–10). An 11-point VNRS >3 was considered inadequate pain relief. If POD (detected by NuDESC ≥1) is suspected, consulting a neurologist or a psychiatrist to confirm suspected POD is required.
Results: In total, 1,608 patients were included. The incidence rate of POD was 2.2%. Age ≥70 years and American Society of Anesthesiologists physical status >III were the risk factors of POD in IVPCA patients. Approximately three-quarters of all POD cases occurred within the first 2 postoperative days. For pain at rest, patients with inadequate pain relief had significantly greater rates of POD than patients with adequate pain relief (day 1, 8.4% vs 1.5%, P<0.001; day 2, 9.6% vs 2.0%, P=0.028; day 3, 4.1% vs 2.1%, P=0.412). However, the incidence of POD was not associated with movement-evoked pain relief. Most (79.9%) POD cases in IVPCA patients showed either one or two symptoms. The symptoms of POD were ranked from high to low as disorientation (65.7%), illusions/hallucinations (37.1%), inappropriate communication (31.4%), inappropriate behavior (25.7%), and psychomotor retardation (14.2%).
Conclusion: The incidence rate of POD in IVPCA patients was low. Further research is warranted concerning POD and IVPCA pain management.

Keywords: postoperative delirium, postoperative analgesia, patient-controlled analgesia

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]