Incidence and Risk Factors for Emergence and PACU Delirium
Elizabeth Card, RN; Christopher Hughes, MD; Christina Tomes, RN; Cathy Lee, RN; Jeanie Woods, RN; Donna Nelson, RN;
Lisa Allen, RN; Amy Graves, MPH; Ayumi Shintani, PhD; Pratik Pandharipande, MD, MSCI
DEPARTMENT OF ANESTHESIOLOGY
The research reported on this poster was supported by Vanderbilt University Medical Center. The investigators retained full independence in the conduct of this research.
INTRODUCTION
METHODS
• Delirium is a form of acute brain dysfunction with reported
• Preoperative, intraoperative, and postoperative data collected,
prevalence between 16-80%, depending on patient population
• Delirium is associated with longer hospital stays, increased
re-admissions, poor cognitive and functional outcomes, and
increased mortality
• Risk factors include: 1) patient-related factors (e.g., age, previous
dementia, diabetes) and 2) iatrogenic factors (e.g., benzodiazepines,
opioids, hypoxemia)
• The CAM-ICU is a validated and well-published tool that allows
for rapid diagnosis of both hyperactive and hypoactive delirium by
RESULTS
Emergence Delirium
including demographics, surgery type, anesthetic length, and
drug exposure
Variable, N = 154
• CAM-ICU, Aldrete Score, and Visual Analog Pain Scale
P
Age
0.34
performed upon PACU admission, 30 min, 1 hr, and discharge
Preop + Intraop Benzo
0.60
• Emergence delirium = agitated emergence per OR staff report or
Preop + Intraop Opioid
0.32
Anesthetic Duration
0.04
Inhalation Agent
0.95
ASA Classification
0.81
positive CAM-ICU on PACU admission
• PACU delirium = positive CAM-ICU at 30 min, 1 hr, or discharge
• Multivariable logistic regression to evaluate a priori defined risk
factors
bedside nurses
• Little data exists about emergence and post anesthesia care unit
PACU Delirium
RESULTS
(PACU) delirium and most prior studies have not utilized validated
Patient Characteristics
Variable, N = 67
delirium monitoring tools, likely missing hypoactive delirium
Variable*
STUDY AIMS
• Aim 1: To study the incidence of emergence and PACU delirium
in postoperative patients
• Aim 2: To study the risk factors for emergence and PACU
delirium in postoperative patients
METHODS
• Co-investigator PACU nurses were trained in delirium monitoring
by research nurses adept at performing the CAM-ICU; inter-rater
reliability was assessed prior to study and proved satisfactory
• We performed a prospective cohort study of adult patients
admitted to the PACU after surgery
• Exclusion criteria included severe baseline dementia, anoxic
Age (yr)
Preop + Intraop Midazolam (mg)
• 0 mg
• 0.5 – 2 mg
• > 2 mg
Preop + Intraop + Postop Midazolam (mg)
• 0 mg
• 0.5 – 2 mg
• > 2 mg
understand English
31%
65%
4%
Anesthetic Duration (min)
140 (87 – 207)
•
•
•
•
1
2
3
4
• Agitated emergence per OR staff
• Positive CAM-ICU on PACU admission
PACU Delirium n (%)
• Positive CAM-ICU at 30 min
• Positive CAM-ICU at 60 min
• Positive CAM-ICU at Discharge
*Median (interquartile range) unless otherwise noted
398 (97%)
53%
35%
12%
3 (2 – 3)
4%
44%
49%
3%
154 (38%)
75 (19%)
124 (33%)
67 (17%)
59 (15%)
32 (8%)
15 (5%)
0.07
0.21
0.006
0.21
*Nonlinear
31%
63%
6%
383 (200 – 554)
ASA Classification
ASA Classification
2 (0 – 2)
Preop + Intraop + Postop Fentanyl
Equivalents (mcg)
Emergent Delirium n (%)
brain injury or neuromuscular disorders, and deaf or unable to
2 (0 – 2)
250 (150 – 383)
• Sevoflurane
• Desflurane
• Isoflurane
Preop + Intraop +
Postop Benzo
Preop + Intraop +
Postop Opioid*
57 (44 – 67)
Preop + Intraop Fentanyl Equivalents (mcg)
Inhalation Agent (N)
Age
N = 400
P
CONCLUSIONS
• Emergence and PACU delirium are common after surgery
• Delirium incidence is highest on emergence and PACU
admission and decreases during PACU stay
• Anesthetic duration is associated with emergence delirium
• Total perioperative opioid administration is associated with PACU
delirium
• Further research is needed to confirm these findings and to
identify additional risk factors for emergence and PACU delirium