Inadequate emergence after anesthesia: emergence delirium and hypoactive emergence in the Postanesthesia Care Unit

Ketofol versus Dexmedetomidine for preventing postoperative delirium in elderly patients undergoing intestinal obstruction surgeries: a randomized controlled study

PURPOSE

Postoperative delirium (POD) is considered the most common postoperative neurological complication in elderly patients. The aim of this study was to evaluate the efficacy of the administration of ketofol versus dexmedetomidine (DEX) for minimizing POD in elderly patients undergoing urgent exploration for intestinal obstruction.

METHODS

This prospective double-blinded randomized clinical trial was conducted on 120 elderly patients undergoing urgent exploration for intestinal obstruction. Patients were randomly allocated to one of the three groups: Group C (control group) patients received normal saline 0.9%, group D received dexmedetomidine, and group K received ketofol (ketamine: propofol was 1:4). The primary outcome was the incidence of POD. Secondary outcomes were incidence of emergence agitation, postoperative pain, consumption of rescue opioids, hemodynamics, and any side effects.

RESULTS

The incidence of POD was statistically significantly lower in ketofol and DEX groups than in the control group at all postoperative time recordings. Additionally, VAS scores were statistically significantly decreased in the ketofol and DEX groups compared to the control group at all time recordings except at 48 and 72 h postoperatively, where the values of the three studied groups were comparable. The occurrence of emergence agitation and high-dose opioid consumption postoperatively were found to be significant predictors for the occurrence of POD at 2 h and on the evening of the 1st postoperative day.

CONCLUSION

The administration of ketofol provides a promising alternative option that is as effective as DEX in reducing the incidence of POD in elderly patients undergoing urgent exploration for intestinal obstruction.

TRIAL REGISTRATION

This clinical trial was approved by the Institutional Review Board (IRB) at Zagazig University (ZU-IRB# 6704// 3/03/2021) and ClinicalTrials.gov (NCT04816162, registration date 22/03/ 2021). The first research participant was enrolled on 25/03/2021).

Development of Postanesthesia Care Unit Delirium Is Associated with Differences in Aperiodic and Periodic Alpha Parameters of the Electroencephalogram during Emergence from General Anesthesia: Results from a Prospective Observational Cohort Study

BACKGROUND

Intraoperative alpha-band power in frontal electrodes may provide helpful information about the balance of hypnosis and analgesia and has been associated with reduced occurrence of delirium in the postanesthesia care unit. Recent studies suggest that narrow-band power computations from neural power spectra can benefit from separating periodic and aperiodic components of the electroencephalogram. This study investigates whether such techniques are more useful in separating patients with and without delirium in the postanesthesia care unit at the group level as opposed to conventional power spectra.

METHODS

Intraoperative electroencephalography recordings of 32 patients who developed perioperative neurocognitive disorders and 137 patients who did not were considered in this post hoc secondary analysis. The power spectra were calculated using conventional methods and the "fitting oscillations and one over f" algorithm was applied to separate aperiodic and periodic components to see whether the electroencephalography signature is different between groups.

RESULTS

At the group level, patients who did not develop perioperative neurocognitive disorders presented with significantly higher alpha-band power and a broadband increase in power, allowing a "fair" separation based on conventional power spectra. Within the first third of emergence, the difference in median absolute alpha-band power amounted to 8.53 decibels (area under the receiver operator characteristics curve, 0.74 [0.65; 0.82]), reaching its highest value. In relative terms, the best separation was achieved in the second third of emergence, with a difference in medians of 7.71% (area under the receiver operator characteristics curve, 0.70 [0.61; 0.79]). The area under the receiver operator characteristics curve values were generally lower toward the end of emergence with increasing arousal.

CONCLUSIONS

Increased alpha-band power during emergence in patients who did not develop perioperative neurocognitive disorders can be traced back to an increase in oscillatory alpha activity and an overall increase in aperiodic broadband power. Although the differences between patients with and without perioperative neurocognitive disorders can be detected relying on traditional methods, the separation of the signal allows a more detailed analysis. This may enable clinicians to detect patients at risk for developing perioperative neurocognitive disorders in the postanesthesia care unit early in the emergence phase.

EDITOR’S PERSPECTIVE

Incidence of Unintentional Intraoperative Hypothermia and Its Risk Factors in Oral and Maxillofacial Surgery: A Prospective Study

PURPOSE

Unintentional intraoperative hypothermia is a common complication in patients who undergo open surgery, increasing the risk of adverse outcomes. However, few studies have focused on intraoperative hypothermia during oral and maxillofacial surgery. Our study aimed to analyze the prevalence and risk factors of hypothermia in patients who underwent oral and maxillofacial surgery.

DESIGN

A prospective cohort study was conducted on 128 patients who underwent oral and maxillofacial surgery.

METHODS

This prospective study was conducted at West China Hospital of Stomatology between December 2020 and May 2021, and each patient was followed for at least 1-month postoperatively. Patients who underwent oral and maxillofacial surgery under general anesthesia, with at least 1-month follow-up were analyzed. The primary variable was intraoperative hypothermia, defined as core body temperature less than 36°C, measured using a tympanic thermometer during the surgery. We performed univariate and multivariate logistic regression analyses to identify the risk factors of unintentional intraoperative hypothermia.

FINDINGS

The mean age of the 128 patients was 31.0 ± 20.9 years, and there was a male predominance (53.1%), with male to female ratio of 1.13:1. Thirty-one patients (24.2%) developed hypothermia intraoperatively. Older age (OR = 1.068, 95% CI: 1.028-1.110, P = .001), lower weight (OR = 0.878, 95% CI: 0.807-0.955, P = .002), greater blood loss (OR = 1.003, 95% CI: 1.000-1.006, P = .034), and undergoing cancer surgery (OR = 0.210, 95% CI: 0.067-0.656, P = .007) were associated with intraoperative hypothermia.

CONCLUSIONS

Unintentional intraoperative hypothermia is common in patients who undergo surgery for oral cancer. Warming interventions to prevent intraoperative hypothermia for high-risk patients (older, lower weight, or more intraoperative bleeding) should be considered. Meanwhile, with careful nursing and rehabilitation instructions, intraoperative hypothermia does not lead to serious perioperative complications.

Comparison of propofol vs. remimazolam on emergence profiles after general anesthesia: A randomized clinical trial

STUDY OBJECTIVE

The emergence profiles in patients undergoing total intravenous anesthesia with either propofol or remimazolam with flumazenil reversal were compared.

DESIGN

A prospective, double-blind, randomized trial.

SETTING

An operating room and a post-anesthesia care unit (PACU).

PATIENTS

Adult patients (n = 100) having American Society of Anesthesiologists (ASA) physical status of I-III undergoing general anesthesia were enrolled and randomly assigned to the propofol or the remimazolam group.

INTERVENTIONS

The propofol group received target-controlled infusion of propofol, and the remimazolam group received continuous infusion of remimazolam. Continuous infusion of remifentanil was used in both groups. For emergence, flumazenil was used in increments of 0.2 mg in the remimazolam group.

MEASUREMENTS

The primary outcome was the time required for the patient to obey verbal commands. The secondary outcomes included the time to bispectral index (BIS) over 80, the time to laryngeal mask airway (LMA) removal, the Richmond Agitation-Sedation Scale (RASS) scores in the PACU, and adverse events throughout the study period.

MAIN RESULTS

The time taken to obey verbal commands was significantly longer in the propofol group than the remimazolam group (14 [9, 19]) vs. 5 [3, 7]) minutes, P < 0.001; median difference -9, 95% confidence interval -11 to -6). The times to BIS over 80 and to LMA removal were also significantly longer in the propofol group. In addition, the RASS score upon arrival to the PACU differed significantly between the two groups (P = 0.006). Re-sedation in the PACU was observed in 11 (22%) of the patients in the remimazolam group.

CONCLUSIONS

Remimazolam-based total intravenous anesthesia with flumazenil reversal may be effective in reducing emergence time, but a significant incidence of re-sedation was observed in the PACU. Further studies are needed to determine adequate dose and timing of routine flumazenil use and minimize the risk of re-sedation.

Effect of preoperative patient education and simulated mouth breathing training on opioid requirements in the post-anesthesia care unit after nasal surgery: a randomized controlled study

BACKGROUND

A simulated education, prior to surgery about postoperative nasal stuffiness and ease of breathing through the mouth may help patients tolerate discomfort after nasal surgery. This study aimed to investigate the effect of preoperative simulated education on immediate postoperative opioid requirements in patients undergoing elective nasal surgery.

METHODS

This randomized controlled trial of 110 patients undergoing nasal surgery randomly allocated patients into either a control (group C) or an education group (group E). One day before surgery, patients in group E were intensively trained to breathe through the mouth by using a nasal clip, with informative explanations about inevitable nasal obstruction and discomfort following surgery. Patients in group C were provided with routine preoperative information. Total intravenous anesthesia (TIVA) with propofol and remifentanil was used for anesthesia. No further opioid was used for analgesia intraoperatively. The primary outcome was index opioid (fentanyl) requirements at the post-anesthesia recovery unit (PACU). Secondary outcomes were emergence agitation, pain scores at the PACU, and postoperative recovery using the Quality of Recovery-15 (QoR15-K).

RESULTS

The rate of opioid use in the PACU was 51.0% in the group E and 39.6% in the group C (p = 0.242). Additional request for analgesics other than index opioid was not different between the groups. Emergence agitation, postoperative pain severity, and QoR15-K scores were comparable between the groups.

CONCLUSION

Preoperative education with simulated mouth breathing in patients undergoing nasal surgery did not reduce opioid requirements.

TRIAL REGISTRATION

KCT0006264; 16/09/2021; Clinical Research Information Services ( https://cris.nih.go.kr ).

Intraoperative body temperature and emergence delirium in elderly patients after non-cardiac surgery: A secondary analysis of a prospective observational study

BACKGROUND

Emergence delirium (ED) is a kind of delirium that occured in the immediate post-anesthesia period. Lower body temperature on post-anesthesia care unit (PACU) admission was an independent risk factor of ED. The present study was designed to investigate the association between intraoperative body temperature and ED in elderly patients undergoing non-cardiac surgery.

METHODS

This study was a secondary analysis of a prospective observational study. Taking baseline body temperature as a reference, intraoperative absolute and relative temperature changes were calculated. The relative change was defined as the amplitude between intraoperative lowest/highest temperature and baseline reference. ED was assessed with the confusion assessment method for intensive care unit at 10 and 30 min after PACU admission and before PACU discharge.

RESULTS

A total of 874 patients were analyzed with a mean age of 71.8 ± 5.3 years. The incidence of ED was 38.4% (336/874). When taking 36.0°C, 35.5°C, and 35.0°C as thresholds, the incidences of absolute hypothermia were 76.7% (670/874), 38.4% (336/874), and 17.5% (153/874), respectively. In multivariable logistic regression analysis, absolute hypothermia (lowest value <35.5°C) and its cumulative duration were respectively associated with an increased risk of ED after adjusting for confounders including age, education, preoperative mild cognitive impairment, American Society of Anesthesiologists grade, duration of surgery, site of surgery, and pain intensity. Relative hypothermia (decrement >1.0°C from baseline) and its cumulative duration were also associated with an increased risk of ED, respectively. When taking the relative increment >0.5°C as a threshold, the incidence of relative hyperthermia was 21.7% (190/874) and it was associated with a decreased risk of ED after adjusting above confounders.

CONCLUSIONS

In the present study, we found that intraoperative hypothermia, defined as either absolute or relative hypothermia, was associated with an increased risk of ED in elderly patients after non-cardiac surgery. Relative hyperthermia, but not absolute hyperthermia, was associated with a decreased risk of ED.

REGISTRATION

Chinese Clinical Trial Registry (No. ChiCTR-OOC-17012734).

Effects of early postoperative neurocognitive disorders on clinically relevant outcomes: a meta-analysis

BACKGROUND

Early postoperative neurocognitive disorders (ePND), include both emergence delirium, which is defined as very early onset postoperative delirium, and emergence agitation, defined as motor arousal. Although research on anesthesia emergence is limited, ePND are likely associated with unfavorable outcomes. This meta-analysis assessed the effect of ePND on clinically relevant outcomes.

METHODS

A systematic search of studies published between 2002 and 2022 on MEDLINE, PubMed, Google Scholar, and the Cochrane Library was performed. Studies that included adults with emergence agitation and/or delirium and reported at least one of the following outcomes: mortality, postoperative delirium, length of post-anesthesia care unit stay, or length of hospital stay were included. The internal validity, risk of bias, and certainty of the evidence were assessed.

RESULTS

A total of 16,028 patients from 21 prospective observational studies and one case-control retrospective study were included in this meta-analysis. The occurrence rate of ePND was 13% (data excluding the case-control study). The mortality rate was 2.4% in patients with ePND vs. 1.2% in the normal emergence group (risk ratio [RR]: 2.6, P = 0.01, very low quality of evidence). Postoperative delirium occurred in 29% of patients with ePND and 4.5% of patients with normal emergence (RR: 9.5, P < 0.001, I2 = 93%). Patients with ePND had a prolonged length of post-anesthesia care unit stay (P = 0.004) and length of hospital stay (P < 0.001).

CONCLUSIONS

This meta-analysis suggests that ePND are associated with twice the risk of mortality and a 9-fold increased risk of postoperative delirium.

Global trends in research related to emergence delirium, 2012–2021: A bibliometric analysis

Introduction

Emergence delirium is a kind of mental disorder during the early awakening period after general anesthesia, which is manifested as the combination of perceptual disturbance and psychomotor agitation. It is an independent risk factor for postoperative delirium and even long-term postoperative cognitive decline, which often affects the postoperative outcome and deserves the attention of clinical anesthesiologists. There are many studies on emergence delirium, but the quantity and quality of these studies are unclear. Therefore, we conducted a bibliometric analysis of studies on emergence delirium between January 2012 and December 2021. Through the analysis of relevant literature, the research hotspots and trends of emergence delirium are understood, which can provide a reference for future research.

Methods

We searched the Web of Science Core Collection (WoSCC) for original articles and reviews related to emergence delirium published between 2012 and 2021, and collected a variety of bibliographic elements, including annual publications, authors, countries/regions, institutions, journals, and keywords. Three different science-based tools (CiteSpace, VOSviewer and Bibliometrix) were used for this comprehensive analysis.

Results

From January 2012 to December 2021, a total of 912 emergence delirium (ED) related literature were published, including 766 original research articles and 146 review articles. The number of publications has increased every year except 2016. The United States published 203 articles, ranking first with China, followed by South Korea (95 articles). The United States is also the country with the most citations (4,508), and Yonsei Univ is the most productive institution. The most published journal was PEDIATRIC ANESTHESIA, with the highest h and g index. LEE JH is the most influential author in this field.

Discussion

“Children, emergence agitation, delirium, dexmedetomidine” are the hot topics in this field in recent years. The bibliometric analysis in this field will provide the future direction for the study of emergence delirium for clinicians.

The impact of emergence delirium on hospital length of stay for children who underwent tonsillectomy/adenotonsillectomy: an observational retrospective study

BACKGROUND

Emergence Delirium (ED) is a combination of disturbance of perception and psychomotor agitation that is common in pediatric patients after general anesthesia, especially at preschool age. Since the effect of ED on the length of stay has been studied in adults but infrequently in children, the aim of this study was to investigate the relationship between ED and length of stay in this population.

METHODS

A single center, retrospective, observational study was carried out in children who underwent tonsillectomy or adenotonsillectomy. The Pediatric Anesthesia Emergence Delirium (PAED) scale was used to assess ED. In addition to the time to hospital discharge (time frame 24 hours), drugs used, comorbidities, early postoperative complications, and pain were investigated if potentially associated with the complication.

RESULTS

Four hundred sixteen children aged from 1.5 to 10 years (183 female, 233 male) were included. ED occurred in 25.5% of patients (n = 106). Patients were divided into the ED group and the No-ED group. The discharge time was similar in both groups. No significant differences were observed in the frequency of postoperative complications. The use of fentanyl or dexmedetomidine did not affect ED occurrence. The frequency of pain was greater in the ED group, both in the recovery room and in the ward (p = 0.01).

CONCLUSIONS

The occurrence of ED in children after tonsillectomy/adenotonsillectomy did not extend the length of stay.

Distributed harmonic patterns of structure-function dependence orchestrate human consciousness

A central question in neuroscience is how consciousness arises from the dynamic interplay of brain structure and function. Here we decompose functional MRI signals from pathological and pharmacologically-induced perturbations of consciousness into distributed patterns of structure-function dependence across scales: the harmonic modes of the human structural connectome. We show that structure-function coupling is a generalisable indicator of consciousness that is under bi-directional neuromodulatory control. We find increased structure-function coupling across scales during loss of consciousness, whether due to anaesthesia or brain injury, capable of discriminating between behaviourally indistinguishable sub-categories of brain-injured patients, tracking the presence of covert consciousness. The opposite harmonic signature characterises the altered state induced by LSD or ketamine, reflecting psychedelic-induced decoupling of brain function from structure and correlating with physiological and subjective scores. Overall, connectome harmonic decomposition reveals how neuromodulation and the network architecture of the human connectome jointly shape consciousness and distributed functional activation across scales.

The Effectiveness of Dexmedetomidine as a Prophylactic Treatment for Emergence Delirium Among Combat Veterans With High Anxiety: A Randomized Placebo-Controlled Trial

INTRODUCTION

Emergence delirium (ED) is characterized by agitation, confusion, and violent physical and verbal behavior associated with awakening from general anesthesia. Combat exposure among U.S. military veterans has been identified as a risk factor for ED. Preoperative baseline anxiety was shown to be a predictor of ED, and combat veterans are known to be at high risk for anxiety as well as depression and PTSD. Dexmedetomidine is an alpha-2 receptor agonist proven to mitigate ED in several patient populations. Perioperative use of dexmedetomidine demonstrated promising benefits in pediatric ED but has not been evaluated in combat veterans.

MATERIALS AND METHODS

This study was a multi-site, prospective, randomized controlled investigation of 369 patients with a history of military combat exposure who were scheduled for elective surgery with a general anesthetic as the primary means of anesthesia. The trial was funded by the Tri-Service Nursing Research Program Grant HU0001-14-TS05 (N14-PO3) and approved by the Institutional Review Boards at the Naval Medical Center San Diego, Womack Army Medical Center, Walter Reed National Military Medical Center, and the Uniformed Services University of the Health Sciences, Bethesda, MD. All subjects were administered the State-Trait Anxiety Inventory (STAI) to evaluate baseline anxiety. Those enrolled subjects with a low anxiety level (STAI < 39) (n = 215) were placed in the observational arm of the study. Those with a high anxiety level (STAI ≥ 39) were placed in the experimental arm (n = 153) and were further randomized to treatment with intraoperative dexmedetomidine infusion (1 μg/kg bolus at induction, followed by a 0.6 μg/kg/h infusion continued until emergence) (n = 75) or a placebo intraoperative infusion (n = 75). Following the delivery of the prescribed anesthetic, all subjects were observed for signs of ED using the Pediatric Anesthesia Emergence Delirium (PAED) Scale. The patient and data recorder remained blinded to the randomization results.

RESULTS

The central tendencies of demographics and clinical characteristics are reported. PAED among those randomized to dexmedetomidine (median 7, interquartile interval (IQI) 5.2-9.2) tended to be less (P < .0001) than that of those randomized to control (median 12, IQI 10-13). Dexmedetomidine was found to be the most important predictor of PAED (35% relative importance), followed by Patient Health Questionnaire (14%), STAI-Trait (9%), and PTSD Checklist-Military Version (8%); the overall rankings are featured. Randomization to receipt of dexmedetomidine was associated with a 3.7-unit reduction (95% CI 2.5-4.9) in PAED (P < .001) in a linear model controlling for several variables, and the directionality of the effect persisted upon regularization in a penalized linear model.

CONCLUSIONS

Dexmedetomidine was effective at reducing PAED among combat veterans who were experiencing symptoms of pre-operative anxiety (i.e., STAI-State ≥39). Although psychological morbidity is not unique to the military population, combat veterans carry some of the highest rates of anxiety, PTSD and depression compared to the general population. Dexmedetomidine can be safety employed by anesthesia providers to reduce symptoms of ED in the perioperative period. The double-blind randomized, controlled study design strengthens our analyses; however, this study did not control for the type of surgical procedure or the duration of anesthetic. Furthermore, we only enrolled patients with combat exposure experiencing symptoms of anxiety and did not investigate the role of dexmedetomidine in combat veterans with less anxiety. Further study of the relationship between psychological comorbidities, ED, and dexmedetomidine is warranted.

Relationship between Fasting Times and Emergence Delirium in Children Undergoing Magnetic Resonance Imaging under Sedation

Background and Objectives: This study aimed to determine whether there is a relationship between preoperative fasting time, fasting blood glucose (FBG), and postoperative emergence delirium (ED) in pediatric patients undergoing MRI under sedation. Materials and Methods: 110 pediatric patients were included in the study. Preoperative fasting (solid-fluid) time and FBG were recorded. The development of ED in the patients who underwent MRI under sedation was evaluated with the pediatric anesthesia emergence delirium (PAED) value for 30 min every 5 min in the recovery room. PAED score of ≥10 was grouped as having ED, and a PAED score of <10 as without ED at any time. The PAED scores were compared with other variables, ASA, age, weight, MRI examination time, and FBG level and fasting times. The risk factors affecting the occurrence of ED were examined. Results: Mean age was 3.94 ± 1.53 years, mean FBG was 106.97 ± 12.53 mg/dL, fasting time was 10.75 ± 2.61 h, solid food fasting time was 11.92 ± 2.33 h, and thirst time was 10.74 ± 2.58 h. FBG was never associated with PAED measurement at any time (p > 0.05). There was a weak positive correlation between the fasting time and the 0th, 5th, and 10th minute PAED score (r = 0.225; p = 0.018, r = 0.195; p = 0.041, r = 0.195; p = 0.041). There was a weak positive correlation between the solid food fasting time and the PAED score at the 0th, 5th, 10th, 15th, and 20th minutes (r = 0.382; p < 0.001, r = 0.357; p < 0.001, r = 0.345; p < 0.001, r = 0.360; p < 0.001, r = 0.240; p < 0.001). There was a weak positive correlation between thirst time and the PAED score at the 0th, 5th, and 10th minutes (r = 0.222; p = 0.020. r = 0.192; p = 0.045, r = 0.199; p = 0.037). The incidence of ED at any time was 34.5%. Conclusions: Prolonged fasting time, solid food fasting time and thirst time are risk factors for developing postoperative ED in children undergoing MRI under sedation.

Delirium in a surgical context from a nursing perspective: A hybrid concept analysis

Background

The term delirium has been defined in medical diagnosis criteria as a multidimensional disorder, and the term acute confusion is included in nursing classifications. Delirium can be a serious complication assessed in a patient after a surgical procedure. Still, the patient's delirium frequently remains unrecognised. Care of patients with delirium after surgical procedure is complex, and it challenges nursing expertise. From the nurses' viewpoint, delirium is associated with ambiguity of concepts and lack of knowledge. Therefore, reseach on how nurses perceive patients with delirium in a surgical context is needed.

Objective

The aim of this study was to describe the concepts of delirium and acute confusion, as well as the associated dimensions, in adult patients in a surgical context from the nursing perspective.

Design

The study used Schwartz and Barcott's hybrid concept analysis with theoretical, fieldwork, and final analytical phases.

Settings

Surgical wards, surgical intensive care units, and post-anaesthesia care units.

Data sources

A systematic literature search was performed through Pubmed (Medline), Cinahl, PsycInfo, and Embase.

Participants

Registered nurses and licensed practical nurses (n = 105) participated in the fieldwork phase.

Methods

In the theoretical phase, the concepts' working definitions were formulated based on a systematic literature search with the year limitations from 2000 until February 2021. At the fieldwork phase, the nurses' descriptions of patients with delirium were analysed using the deductive content analysis method. At the final analytical phase, findings were combined and reported.

Results

The concepts of delirium, subsyndromal delirium, and acute confusion are well defined in the literature. From the perspective of the nurses in the study, concepts were seen as a continuum not as individual diagnoses. Nurses described the continuum of delirium as a process with acute onset, duration, and recovery with the associated dimensions of symptoms, symptom severity, risk factors, and early signs. The acute phase of delirium was emphasised, and preoperative or prolonged disturbance did not seem to be relevant in the surgical care context. Patients' compliance with care may be decreased with the continuum of delirium, which might challenge both patients' recovery from surgery and the quality of nursing care.

Conclusions

In clinical practice the nurses used term confusion inaccurately. The term acute confusion might be used when illustrating an early stage of delirium. Nurses could benefit from further education where the theoretical knowledge is combined with the clinical practice. The discussion about the delirium, which covers the time both before surgery and after the acute phase should be increased.

The Assessment of Immediate Postoperative Delirium in Neurologically Intact Adult Patients Admitted to the Post-anesthesia Care Unit: A Cross-Sectional Study

Background

Immediate postoperative delirium (IPD) in the post-anesthesia care unit (PACU) can cause significant morbidity affecting everyday activities and length of stay with cost implications. This study was undertaken to find the proportion of IPD in PACU and its association with anesthesia and other perioperative factors.

Methods

After obtaining ethical approval and informed consent, this cross-sectional study was conducted in the PACU. A total of 600 consecutive adult patients (American Society of Anesthesiologists (ASA) 1-3) posted for surgery were approached between January and March 2019, of which 402 patients without neurological diseases and language and hearing discrepancies were studied. All patients had the intervention of surgery under anesthesia in a usual manner. Delirium was assessed preoperatively, postoperatively at 15 and 30 minutes, and before discharge from the PACU. IPD was assessed using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) score, while sedation/agitation was assessed using the Richmond Agitation-Sedation Scale (RASS). The primary outcomes were the proportion of IPD, association with anesthesia, and perioperative risk factors. The secondary outcomes were the length of stay, delirium treatment, and mortality.

Results

Overall, the IPD proportion was 14.7%. A significant association was demonstrated with premedication with midazolam (odds ration (OR): 3.2; 95% confidence interval (CI): 1.42-7.35; P=0.003), general anesthesia (GA) (OR: 6.3; 95% CI: 2.23-17.8; P<0.001), duration of anesthesia (126 versus 95 minutes; P=0.001), laparoscopic mode of surgical access (OR: 3.4; 95% CI: 1.8-6.4; P<0.001), and postoperative RASS >/< 0 (OR: 10.6; 95% CI: 4.69-24.11; P<0.001) at 30 minutes and before discharge from the PACU. Multivariate analysis showed the strongest association of RASS at 30 minutes with IPD.

Conclusion

The proportion of IPD was found to be 14.7% in this study, and the chances of developing IPD are high if the patient is not awake and calm in the PACU, especially if midazolam is administered as premedication, followed by general anesthesia (GA) for a long duration.

The absence of dominant alpha-oscillatory EEG activity during emergence from delta-dominant anesthesia predicts neurocognitive impairment- results from a prospective observational trial

STUDY OBJECTIVE

Postoperative neurocognitive disorders (PND) are common complications after surgery under general anesthesia. In our aging society the incidence of PND will increase. Hence, interdisciplinary efforts should be taken to minimize the occurrence of PND. Electroencephalographic (EEG) monitoring of brain activity during anesthesia or emergence from anesthesia is a promising tool to identify patients at risk. We therefore investigated whether we could identify specific EEG signatures during emergence of anesthesia that are associated with the occurrence of PND.

DESIGN AND PATIENTS

We performed a prospective observational investigation on 116 patients to evaluate the EEG features during emergence from general anesthesia dominated by slow delta waves in patients with and without delirium in the postoperative care unit (PACU-D) as assessed by the CAM-ICU and the RASS.

MAIN RESULTS

During emergence both the frontal and global EEG of patients with PACU-D were significantly different from patients without PACU-D. PACU-D patients had lower relative alpha power and reduced fronto-parietal alpha coherence.

CONCLUSIONS

With our analysis we show differences in EEG features associated with anesthesia emergence in patients with and without PACU-D. Frontal and global EEG alpha-band features could help to identify patients with PACU-D.

CLINICAL TRIAL NUMBER

NCT03287401.

A Cross-Sectional Survey on the Clinical Management of Emergence Delirium in Adults: Knowledge, Attitudes, and Practice in Mainland China

Background: Emergence delirium (ED) occurs immediately after emergence from general anesthesia, which may have adverse consequences. This cross-sectional survey assessed Chinese physicians’ and nurses’ knowledge of, attitudes towards, and practice regarding ED in adults. Methods: Electronic questionnaires were sent to 93 major academic hospitals across mainland China and both attending anesthesiologists and anesthesia nurses were recommended to complete them. Results: A total of 243 anesthesiologists and 213 anesthesia nurses participated in the survey. Most of the participants considered it a very important issue; however, less than one-third of them routinely assessed ED. In terms of screening tools, anesthesiologists preferred the Confusion Assessment Method, while anesthesia nurses reported using multiple screening tools. Divergence also appeared with regard to the necessity of monitoring the depth of anesthesia. Anesthesiologists considered it only necessary in high-risk patients, while the nurses considered that it should be carried out routinely. No unified treatment strategy nor medication was reported for ED treatment during the recovery period. Conclusions: This study illustrated that there are high awareness levels among both Chinese anesthesiologists and anesthesia nurses regarding the importance of ED. However, a specific practice in terms of routine delirium assessment, anesthesia depth monitoring, and a standardized treatment algorithm needs to be implemented to improve ED management.

Instruments to Identify Delirium in Patients Recovering From Anesthesia: A Scoping Review

PURPOSE

To identify the validated instruments used for screening and detecting postoperative delirium (POD) during Post Anesthesia Recovery (PAR) period, and the incidence and associated risk factors with POD.

DESIGN

A scoping review.

METHODS

The study search occurred in May 2021 in the PubMed, Embase, Scopus, CINAHL, Web of Science and LILACS databases. Primary studies that used validated instruments for screening and detecting POD in the PAR period were included.

FINDINGS

A total of 38 articles were included. The most used instruments were CAM-ICU, Nu-DESC, and RASS. The instruments that screened and detected delirium earliest were the Nu-DESC and CAM-ICU. POD incidence was up to 20% in more than half of the included studies. Cardiovascular comorbidities, chronic kidney disease, low functional reserve, chronic obstructive pulmonary disease and postoperative pain were among the primary risk factors.

CONCLUSION

The instrumentsshowing the greatest accuracy for screening and detecting POD in the PAR period were the Nu-DESC and CAM-ICU.

Effect of Preoperative Thoracic Paravertebral Blocks on Emergence Agitation During Tracheal Extubation: A Randomized Controlled Trial

Objective

This study aims to compare the effects of preoperative thoracic paravertebral blocks (TPVB) with intercoastal nerve blocks (ICNB) on emergence agitation (EA) during tracheal extubation in patients who underwent thoracoscopic lobectomy.

Design, Setting, and Participants

A randomized clinical trial was conducted in patients undergoing thoracoscopic lobectomy at Beijing Chest Hospital between June 2019 and December 2020.

Interventions

Patients were randomly assigned 1:1 to receive either ultrasound-guided preoperative TPVB or ICNB.

Main Outcomes and Measures

The primary outcome was the occurrence of emergency agitation, which was evaluated by Aono’s four-point scale (AFPS). Secondary outcomes included hemodynamics [mean arterial pressure (MAP) and heart rate (HR)]; and post-operative pain intensity [visual analog scale (VAS), Ramsay sedation score (RSS), and patient-controlled analgesia (PCA) demand times].

Results

Among the 100 patients aged 55–75 years old, 50 were randomized to each group; 97 patients completed the trial. Compared to the ICNB group, the occurrence of EA in the TPVB group was significantly lower [31.3% (15/48) vs. 12.2% (6/49), relative risk = 1.276, 95% CI: 1.02–1.60, P = 0.028]. For patients in the TPVB group, the MAP and HR at 5, 10, and 30 min after extubation were significantly lower; the intraoperative details including emergence time, extubation time, and consumption of sufentanil were significantly shorter than that in the ICNB group. Additionally, patients in the TPVB group showed significantly lower VAS at rest or coughing and significantly lower RSS at 60 and 240 min after extubation than patients in the ICNB group (all P < 0.05).

Conclusion

Preoperative TPVB was associated with less EA during tracheal extubation when compared with ICNB in patients undergoing thoracoscopic lobectomy.

Clinical Trial Registration

[http://www.chictr.org.cn/index.aspx], identifier [ChiCTR1900023852].

Whole-brain modelling identifies distinct but convergent paths to unconsciousness in anaesthesia and disorders of consciousness

The human brain entertains rich spatiotemporal dynamics, which are drastically reconfigured when consciousness is lost due to anaesthesia or disorders of consciousness (DOC). Here, we sought to identify the neurobiological mechanisms that explain how transient pharmacological intervention and chronic neuroanatomical injury can lead to common reconfigurations of neural activity. We developed and systematically perturbed a neurobiologically realistic model of whole-brain haemodynamic signals. By incorporating PET data about the cortical distribution of GABA receptors, our computational model reveals a key role of spatially-specific local inhibition for reproducing the functional MRI activity observed during anaesthesia with the GABA-ergic agent propofol. Additionally, incorporating diffusion MRI data obtained from DOC patients reveals that the dynamics that characterise loss of consciousness can also emerge from randomised neuroanatomical connectivity. Our results generalise between anaesthesia and DOC datasets, demonstrating how increased inhibition and connectome perturbation represent distinct neurobiological paths towards the characteristic activity of the unconscious brain.

Perturbations in a large-scale whole-brain model suggest that anesthesia and injury may be imparting functionally similar effects in terms of brain dynamics.

Incidence of and Risk Factors for Emergence Delirium and Postoperative Delirium in Neurosurgical Patients- A Prospective Cohort Study

Background

Delirium after surgery is a spectrum of clinical syndrome constituting emergence delirium (ED) and/or postoperative delirium (POD).

Objectives

The primary objective of this study was to evaluate the incidence of ED and POD in patients after neurosurgical procedures. The secondary objectives were to examine the relationship between ED and POD and identify perioperative risk factors of ED and POD.

Materials and Methods

This is a prospective cohort study conducted at the National Institute of Mental Health and Neurosciences. After obtaining the ethics committee approval, consecutive adult patients scheduled for elective neurosurgical procedures from February 2018 to November 2018 were included. We excluded children, patients with preoperative Glasgow Coma score <15, and patients with preoperative delirium. ED was assessed using Riker's Sedation-Agitation Score and POD was assessed using Confusion Assessment Method. Data collection included patient demographics, details of anesthetics and analgesics, and neurosurgical details.

Results

The incidence of ED and POD was 41% (N = 82/200) and 20% (N = 40/200), respectively. The occurrence of ED and POD coexisting as a continuous spectrum was 15%. Patients undergoing spine surgeries were found to have 44% less risk of ED than after cranial surgeries (P = 0.032). Presence of ED was associated with 1.8 times higher risk of POD (P < 0.001) and male gender was associated with 2.5 times higher risk of POD (P = 0.005).

Conclusions

Incidences of ED and POD are higher after neurosurgery as compared with that reported in nonneurosurgical population previously.

Effects of Increased Optic Nerve Sheath Diameter on Inadequate Emergence from Anesthesia in Patients Undergoing Robot-Assisted Laparoscopic Prostatectomy: A Prospective Observational Study

(1) Background: Robot-assisted laparoscopic prostatectomy (RALP) is preferred over open prostatectomy because it offers superior surgical outcomes and better postoperative recovery. The steep Trendelenburg position and pneumoperitoneum required in Robot-assisted laparoscopic prostatectomy, however, increase intracranial pressure (ICP). The present study aimed to evaluate the effects of elevated ICP on the quality of emergence from anesthesia. (2) Methods: Sixty-seven patients undergoing RALP were enrolled. We measured optic nerve sheath diameter at four timepoints during surgery. Primary outcome was inadequate emergence in the operating room (OR). Secondary outcomes were postoperative neurologic deficits of dizziness, headache, delirium, cognitive dysfunction, and postoperative nausea and vomiting (PONV). (3) Results: A total of 69 patients were screened for eligibility and 67 patients completed the study and were included in the final analysis. After establishing pneumoperitoneum with the Trendelenburg position, ONSD increased compared to baseline by 11.4%. Of the 67 patients, 36 patients showed an increase of 10% or more in optic nerve sheath diameter (ONSD). Patients with ΔONSD ≥ 10% experienced more inadequate emergence in the OR than those with ΔONSD < 10% (47.2% vs. 12.9%, p = 0.003). However, other variables related to the quality of emergence from anesthesia did not different significantly between groups. Similarly, neurologic deficits, and PONV during postoperative day 3 showed no significant differences. (4) Conclusions: ICP elevation detected by ultrasonographic ONSD measurement was associated with a transient, inadequate emergence from anesthesia.

Incidence, risk factors, and consequences of emergence delirium after elective brain tumor resection

BACKGROUND

Emergence delirium (ED) is a common phenomenon occurring in the recovery period. The aim of this study was to investigate the incidence, risk factors, and consequences of ED in adults after elective brain tumor resection.

METHODS

We retrospectively analyzed the data of a prospective cohort performed in a tertiary university hospital. Adult patients admitted to the intensive care unit (ICU) immediately after elective brain tumor resection were consecutively enrolled. Level of consciousness was assessed using the Richmond Agitation-Sedation Scale and ED was assessed using the Confusion Assessment Method for the ICU. Risk factors for ED were determined by multivariable logistic regression.

RESULTS

A total of 659 patients met the inclusion criteria, of which 41 patients with coma were excluded. Among the remaining 618 patients, 131 (21.2%) developed ED. Independent risk factors for ED were: age, education level, use of anticholinergic and mannitol, Glasgow Coma Score and arterial partial pressure of oxygen postoperatively, postoperative pain, malignant tumor, and frontal approach craniotomy. ED was associated with increased postoperative delirium, longer length of hospital stay, and higher hospitalization costs. There was no significant difference in the neurological function deficits (modified Rankin Scale score) between ED and non-ED groups.

CONCLUSIONS

ED has a high incidence and is associated with poor outcomes in adults after elective brain tumor resection. Early screening and prevention for ED should be established in perioperative management of this population.

Inadequate emergence after anesthesia for elective cancer surgery: a single-center cohort study

Background

Inadequate emergence after anesthesia (IEA) is a common phenomenon in adult patients undergoing anesthesia. The aim of this study was to evaluate the incidence and determinants of IEA for elective cancer surgery, and to study its influence on the quality of recovery.

Methods

In this observational, prospective study, 148 patients scheduled for elective cancer surgery were included. IEA was considered for patients having emergence delirium or hypoactive emergence applying The Richmond Agitation and Sedation Scale (RASS) 10 minutes after admission at PACU. Postoperative Quality of Recovery Scale (PQRS) was used at baseline and after surgery at minutes 15 (T15) and 40 (T40), and days 1 (D1) and 3 (D3).

Results

Of the 148 patients, 48 (32%) had IEA. Complete recovery at PQRS was less frequent in patients with IEA on physiological domain at T15 and D1, and activities of daily living domain at D3. Patients with IEA recovered more frequently in emotive domain at T15, T40, and D3. Determinants of IEA were age, risk of surgery, congestive heart disease, cerebrovascular disease, ASA physical status, RCRI score, and duration of anesthesia. IEA patients had more frequently postoperative delirium and stayed for longer at PACU and at the hospital.

Conclusion

IEA was a common phenomenon after anesthesia for elective curative surgery for cancer. Patients with IEA were older and had more comorbidities and a higher surgical risk. Patients with IEA had a less frequent complete recovery on the PD and in AD domains, and a more frequent complete recovery on the ED.

Risk factors for emergence agitation in adults after general anesthesia: A systematic review and meta-analysis

BACKGROUND

Emergence agitation (EA) is an adverse post-operative complication that increases the risk for injury, self-extubation, hemorrhages, and prolonged hospitalization. This meta-analysis aims to define the risk factors for adult EA after general anesthesia and provide recommendations for clinical practice.

METHODS

Embase, PubMed, Medline, and the Cochrane Library databases were comprehensive retrieved. Observational studies that reported the risk factors for adult EA were enrolled. Review Manager 5.4 was used to analyze the extracted data.

RESULTS

Eighteen observational studies involving 16, 678 adult patients were enrolled in this study. Eighteen pre-operative and nineteen intraoperative factors with unadjusted data, and five pre-operative and five intraoperative factors with adjusted data were meta-analyzed separately. Among them, seven factors (age, male, smoking, history of substance misuse, inhalational anesthesia, urinary catheter, complain of pain, or need analgesic drug use in post-anesthetic care unit) were the risk factors no matter meta-analyzed by unadjusted data or adjusted data. Intraoperative use of benzodiazepines was the risk factor when meta-analyzed by adjusted data, but not unadjusted data. Moreover, age and inhalational anesthesia were not the risk factors when omitted one study for sensitivity analysis, and history of substance misuse could not do sensitivity analysis.

CONCLUSION

Based on this meta-analysis, male, smoking, urinary catheter, and post-operative pain are the risk factors, while age, inhalational anesthesia, history of substance misuse, and intraoperative use of benzodiazepines are the possible risk factors for adult EA.

EDITORIAL COMMENT

This systematic review and meta-analysis identify risk factors associated with the occurrence of agitation during emergence from general anesthesia. As might be expected, the strongest factors are generally things which are irritating or painful for patients, but cannot necessarily be avoided.

Malnutrition is not related with emergence delirium in older patients after noncardiac surgery

Background

Delirium is one of the most common complications in older surgical patients. Although previous studies reported that preoperative malnutrition was related with postoperative delirium (POD), there was lack of evidence to illustrate the relationship between malnutrition and emergency delirium (ED). The objective of this study was to investigate the relationship between preoperative malnutrition and ED in older patients undergoing noncardiac surgery.

Methods

The study was carried out in accordance with STROBE guidelines. This was a secondary analysis of a prospective cohort study. Older patients (65–90 years) who underwent noncardiac surgery under general anesthesia were enrolled in Peking University First Hospital.

Results

915 patients were enrolled. The incidence of malnutrition was 53.6 % (490/915). The incidence of emergency delirium was 41.8 % (205/490) in malnutrition group and 31.5 % (134/425) in control group, P < 0.001. After adjusting confounding factors (i.e., age, cognitive impairment, American Society of Anesthesiologists classification (ASA), duration of surgery, pain score, low body temperature and allogeneic blood transfusion), malnutrition was not associated with increased risk of emergency delirium (OR = 1.055, 95 % CI 0.767–1.452, P = 0.742).

Conclusions

Malnutrition was common in older patients undergoing non-cardiac surgery, but it’s not related with emergence delirium after adjusted for confounders.

Trial registration

Chinese Clinical Trial Registry (http://www.chictr.org.cn) (ChiCTR-OOC-17,012,734).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02270-2.

Agreement Between the Mini-Cog in the Preoperative Clinic and on the Day of Surgery and Association With Postanesthesia Care Unit Delirium: A Cohort Study of Cognitive Screening in Older Adults

BACKGROUND

Cognitive impairment is common in older surgical patients and is associated with postoperative delirium. However, cognitive function is inconsistently assessed preoperatively, leading to missed opportunities to recognize vulnerable patients. We designed a prospective cohort study to assess the agreement of the Mini-Cog screening tool administered in the preoperative clinic (clinic-day test) or immediately before surgery (surgery-day test) and to determine whether a positive screening for cognitive dysfunction in the surgery-day test is associated with postoperative delirium in the postanesthesia care unit (PACU).

METHODS

This was a cohort study of patients aged 65-89 years, scheduled for elective, inpatient surgery under general anesthesia between June 20, 2018 and August 3, 2018. Mini-Cog test scores were obtained during a clinic-day test and surgery-day test. The Short Confusion Assessment Method was performed in the PACU. Agreement between Mini-Cog clinic-day and surgery-day test scores was estimated using an ordinally weighted kappa statistic, κ. Multivariable logistic regression was used to determine whether there was an association between a positive screen for cognitive impairment and PACU delirium. Odds ratio analysis was performed to determine whether the Mini-Cog score was associated with PACU delirium.

RESULTS

Of 128 patients meeting eligibility criteria, 80 patients were enrolled. Ten had cognitive impairment based on the Mini-Cog clinic-day test score, while 70 did not. Age, sex, race, education level, subjective memory impairment, and American Society of Anesthesiologists (ASA) physical status were equivalent in the 2 groups. The mean number of days between the clinic-day score and the surgery-day score was 8.4 days (standard deviation [SD] = 6.9). Mini-Cog clinic-day and surgery-day scores had high agreement (κ = 0.78; 95% confidence interval [CI], 0.69-0.87; P < .001), and both scores were highly predictive of PACU delirium. Patients with Mini-Cog surgery-day scores compatible with cognitive impairment (Mini-Cog scores ≤2) had an estimated 12.8 times higher odds of PACU delirium compared to patients with normal cognitive function or Mini-Cog scores >2 (odds ratio [OR] = 12.8; 95% CI, 2.6-63.8, P = .002). Similarly, patients with Mini-Cog clinic-day test scores compatible with cognitive impairment had an estimated 29 times higher odds of PACU delirium compared to patients with normal cognitive function (OR = 29.0; 95% CI, 2.6-63.8, P < .001).

CONCLUSIONS

These data support the approach of using the Mini-Cog on the day of surgery to screen for cognitive impairment in older patients. Importantly, Mini-Cog surgery-day test scores compatible with cognitive impairment (≤2) were strongly associated with PACU delirium.

Cognitive status of patients judged fit for discharge from the post-anaesthesia care unit after general anaesthesia: a randomized comparison between desflurane and propofol

Background

The Aldrete’s score is used to determine when a patient can safely leave the Post-Anaesthesia Care Unit (PACU) and be transferred to the surgical ward. The Aldrete score is based on the evaluation of vital signs and consciousness. Cognitive functions according to the anaesthetic strategy at the time the patient is judged fit for discharge from the PACU (Aldrete’s score ≥ 9) have not been previously studied. The aim of this trial was to assess the cognitive status of inpatients emerging either from desflurane or propofol anaesthesia, at the time of PACU discharge (Aldrete score ≥ 9).

Methods

Sixty adult patients scheduled for hip or knee arthroplasty under general anaesthesia were randomly allocated to receive either desflurane or propofol anaesthesia. Patients were evaluated the day before surgery using Digit Symbol Substitution Test (DSST), Stroop Color Test and Verbal Learning Test. After surgery, the Aldrete score was checked every 5 min until reaching a score ≥ 9. At this time, the same battery of cognitive tests was applied. Each test was evaluated separately. Cognitive status was reported using a combined Z score pooling together the results of all 3 cognitive tests.

Results

Among the 3 tests, only DSST was significantly reduced at Aldrete Score ≥ 9 in the Desflurane group. Combined Z-scores at Aldrete Score ≥ 9 were (in medians [interquartils]): − 0.2 [− 1.2;+ 0.6] and − 0.4 [− 1.1;+ 0.4] for desflurane and propofol groups respectively (P = 0.62). Cognitive dysfunction at Aldrete score ≥ 9 was observed in 3 patients in the Propofol group and in 2 patients in the Desflurane group) (P = 0.93).

Conclusion

No difference was observed in cognitive status at Aldrete score ≥ 9 between desflurane and propofol anaesthesia. Although approximately 10% of patients still had cognitive dysfunctions, an Aldrete score ≥ 9 was associated with satisfactory cognitive function recovery in the majority of the patients after lower limb arthroplasty surgery under general anaesthesia.

Trial registration

Clinical Trials identifier NTC02036736.

Adult Emergence Agitation: A Veteran-Focused Narrative Review

Emergence agitation (EA) is a self-limited state of psychomotor excitement during awakening from general anesthesia. EA is confined to the emergence period as consciousness is restored, which sharply distinguishes it from other postoperative delirium states. Sporadic episodes of EA may become violent with the potential for harm to both patients and caregivers, but the long-term consequences of such events are not fully understood. Current literature on EA in adults is limited to small-scale studies with inconsistent nomenclature, variable time periods that define emergence, a host of different surgical populations, and conflicting diagnostic criteria. Therefore, true incidence rates and risk factors are unknown. In adult noncardiac surgery, the incidence of EA is approximately 19%. Limited data suggest that young adults undergoing otolaryngology operations with volatile anesthetic maintenance may be at the highest risk for EA. Currently suggested EA mechanisms are theoretical but might reflect underblunted sympathetic activation in response to various internal (eg, flashbacks or anxiety) or external (eg, surgical pain) stimuli as consciousness returns. Supplemental dexmedetomidine and ketamine may be utilized for EA prevention. Compared to the civilian population, military veterans may be more vulnerable to EA due to high rates of posttraumatic stress disorder (PTSD) manifesting as violent flashbacks; however, confirmatory data are limited. Nonetheless, expert military medical providers suggest that use of patient-centered rapport tactics, PTSD trigger identification and avoidance, and grounding measures may alleviate hyperactive emergence phenomena. Future research is needed to better characterize EA in veterans and validate prophylactic measures to optimize care for these patients. This narrative review provides readers with an important framework to distinguish EA from delirium. Furthermore, we summarize current knowledge of EA risk factors, mechanisms, and adult management strategies and specifically revisit them in the context of veteran perioperative health. The anesthesiology care team is ideally positioned to further explore EA and develop effective prevention and treatment protocols.

Nursing Delirium Screening Scale, a Tool for Early Detection of Delirium: Integrative Review

Objective: To analyze the context and use of the Nursing Delirium Screening Scale (Nu-DESC) for early detection of delirium in adult patients, compiling the available evidence. Method: Searching for relevant articles on databases such as Cinahl, Medline, Ovid, Scopus, and Web of Science. Inclusion criteria: Articles written in English, Spanish, and Portuguese, published between January 2013 and October 2019. Search terms: “nursing delirium screen,” “inpatient delirium screening,” and “nursing assessment.” We identified 23 articles in which the Nu-DESC was used. Two reviewers independently assessed the articles using the CASPe (Critical Appraisal Skills Program in Spanish) tool. Results: The Nu-DESC is employed in different contexts such as the adult intensive care unit (ICU), post-anesthetic care unit (PACU), palliative care unit, and hospitalization unit. It is more frequently used in the PACU with a more sensitive threshold (≥ 1); the test showed greater sensitivity of 54.5 % (95 % CI: 32.2–75.6) and specificity of 97.1 % (95 % CI: 95.3–98.4). Conclusion: The Nu-DESC facilitates the recognition of delirium episodes by the nursing team, makes care quicker and individualized for each patient, avoiding immediate pharmacological interventions, and coordinate interdisciplinary actions for diagnosis, especially in post-anesthetic care units.

Delayed Emergence from Anesthesia: What We Know and How We Act

The emergence from anesthesia is the stage of general anesthesia featuring the patient’s progression from the unconsciousness status to wakefulness and restoration of consciousness. This complex process has precise neurobiology which differs from that of induction. Despite the medications commonly used in anesthesia allow recovery in a few minutes, a delay in waking up from anesthesia, called delayed emergence, may occur. This phenomenon is associated with delays in the operating room, and an overall increase in costs. Together with the emergence delirium, the phenomenon represents a manifestation of inadequate emergence. Nevertheless, in delayed emergence, the transition from unconsciousness to complete wakefulness usually occurs along a normal trajectory, although slowed down. On the other hand, this awakening trajectory could proceed abnormally, possibly culminating in the manifestation of emergence delirium. Clinically, delayed emergence often represents a challenge for clinicians who must make an accurate diagnosis of the underlying cause to quickly establish appropriate therapy. This paper aimed at presenting an update on the phenomenon, analyzing its causes. Diagnostic and therapeutic strategies are addressed. Finally, therapeutic perspectives on the “active awakening” are reported.

Comparison of Bispectral Index-Guided Individualized Anesthesia with Standard General Anesthesia on Inadequate Emergence and Postoperative Delirium in Elderly Patients Undergoing Esophagectomy: A Retrospective Study at a Single Center

Background

Elderly patients are susceptible to general anesthetics, with a higher bispectral index (BIS) at loss of consciousness (LOC) achieved by propofol infusion compared with young patients. Overexposure to general anesthetics can have adverse effects such as inadequate emergence and postoperative delirium (PD). This study aimed to compare the effects of BIS-guided individualized anesthesia with standard general anesthesia on emergence and delirium after esophagectomy.

Material/Methods

Data on 161 elderly patients undergoing esophagectomy for cancer were retrospectively obtained from electronic medical records. We performed propensity score matching analysis between patients receiving individualized anesthesia (BIS value maintained at about 10 less than the value at LOC) and those receiving standard anesthesia (BIS value maintained at 40–60). In addition, we conducted univariate and multivariate logistic analyses in the entire cohort.

Results

Patients receiving individualized anesthesia had higher BIS values and a lower propofol requirement during surgery than those receiving standard general anesthesia (P<0.05). The overall incidences of inadequate emergence and PD were 37.9% and 18.0% (n=161), respectively. Logistic regression analysis revealed that the independent risk factors for PD were organic brain disease (odds ratio [OR] 6.308; 95% confidence interval [CI] 2.458–16.187) and inadequate emergence (OR 4.063; 95% CI 1.645–10.033).

Conclusions

BIS-guided individualized anesthesia (lighter) does not reduce inadequate emergence or PD compared with standard general anesthesia in elderly patients undergoing esophagectomy. Independent risk factors for PD include organic brain disease and inadequate emergence.

Emergence Delirium in Elderly Patients as a Potential Predictor of Subsequent Postoperative Delirium: A Descriptive Correlational Study

PURPOSE

This study aimed to investigate the incidence of emergence delirium (ED) in elderly patients under general anesthesia and to determine the correlation between ED and delirium at five subsequent postoperative days.

DESIGN

This research is a descriptive correlational study.

METHODS

A total of 168 aged patients undergoing elective general anesthesia were recruited from a comprehensive tertiary teaching hospital with 2,400 beds in Southern China from April 2018 to September 2018. The Nursing Delirium Screening Scale was used to assess delirium at 30 and 60 minutes after extubation or on discharge from the postanesthesia care unit. Patients were assessed for delirium at postoperative days one through five using the same method. Patients' demographic information, including cognitive function, were collected.

FINDINGS

Among the 168 aged patients, 58 suffered from ED (34.5%), including the 79.3% for the 46 patients who experienced postoperative delirium (POD). A positive correlation existed between ED and POD (χ² = 111.744; P < .01). Logistic regression analysis included seven variables: age, preoperative Mini-Mental State Examination score, underlying diseases, American Society of Anesthesiologists grade, surgery duration, postoperative complications, and the presence of ED. Age and ED were concluded to be independent predictive factors of POD.

CONCLUSIONS

ED in the first hour after tracheal tube removal is a predictor of delirium at five subsequent postoperative days. Accurate and timely assessment of recovery period can effectively guide the treatment and rehabilitation of POD and maximize prevention of adverse consequences.

Emergence delirium is associated with increased postoperative delirium in elderly: a prospective observational study

Background

The clinical significance of emergence delirium remains unclear. The purpose of this study was to investigate the association between emergence delirium and postoperative delirium in elderly after general anesthesia and surgery.

Methods

This prospective observational study was done in a tertiary hospital in Beijing, China. Elderly patients (65–90 years) who underwent major noncardiac surgery under general anesthesia and admitted to the postanesthesia care unit (PACU) after surgery were enrolled. Emergence delirium was assessed with the Confusion Assessment Method for the Intensive Care Unit during PACU stay. Postoperative delirium was assessed with the Confusion Assessment Method during the first 5 postoperative days. The association between emergence delirium and postoperative delirium was analyzed with a multivariable logistic regression model.

Results

A total of 942 patients were enrolled and 915 completed the study. Emergence delirium developed in 37.0% (339/915) of patients during PACU stay; and postoperative delirium developed in 11.4% (104/915) of patients within the first 5 postoperative days. After adjusted confounding factors, the occurrence of emergence delirium is independently associated with an increased risk of postoperative delirium (OR 1.717, 95% CI 1.078–2.735, P = 0.023). Patients with emergence delirium stayed longer in PACU and hospital after surgery, and developed more non-delirium complications within 30 days.

Conclusions

Emergence delirium in elderly admitted to the PACU after general anesthesia and major surgery is independently associated with an increased risk of postoperative delirium. Patients with emergence delirium had worse perioperative outcomes.

Chinese Clinical Trial Registry (chictr.org.cn) ChiCTR-OOC-17012734

Electronic supplementary material

The online version of this article (10.1007/s00540-020-02805-8) contains supplementary material, which is available to authorized users.

Emergence agitation: current knowledge and unresolved questions

Emergence agitation (EA), also referred to as emergence delirium, can have clinically significant consequences. The mechanism of EA remains unclear. The proposed risk factors of EA include age, male sex, type of surgery, emergency operation, use of inhalational anesthetics with low blood-gas partition coefficients, long duration of surgery, anticholinergics, premedication with benzodiazepines, voiding urgency, postoperative pain, and the presence of invasive devices. If preoperative or intraoperative objective monitoring could predict the occurrence of agitation during emergence, this would help to reduce its adverse consequences. Several tools are available for assessing EA. However, there are no standardized clinical research practice guidelines and its incidence varies considerably with the assessment tool or definition used. Total intravenous anesthesia, propofol, μ-opioid agonists, N-methyl-D-aspartate receptor antagonists, nefopam, α2-adrenoreceptor agonists, regional analgesia, multimodal analgesia, parent-present induction, and preoperative education for surgery may help in preventing of EA. However, it is difficult to identify patients at high risk and apply preventive measures in various clinical situations. The risk factors and outcomes of preventive strategies vary with the methodologies of studies and patients assessed.This review discusses important outcomes of research on EA and directions for future research.

Postanesthesia care unit delirium following robot-assisted vs open retropubic radical prostatectomy: A prospective observational study

BACKGROUND

The aim of this study was to compare the incidence of early postoperative delirium in the postanesthesia care unit (PACU) between robot-assisted radical prostatectomy (RARP) in the extreme Trendelenburg position and open retropubic radical prostatectomy (ORP) in supine position.

METHODS

Patients were screened for delirium signs 15, 30, 45, and 60 minutes following extubation.

RESULTS

PACU delirium was present in 39.3% of RARP (64/163) patients and 41.8% of ORP (77/184) patients. Higher age (OR 1.072, 95%CI: 1.034-1.111, P < .001), total intravenous anesthesia (OR 2.001, 95%CI: 1.243-3.221, P = .004), and anesthesia duration (OR 1.255, 95%CI: 1.067-1.476, P = .006) were associated with PACU delirium, but no association was found between surgical technique and PACU delirium.

CONCLUSION

Compared with inhalational anesthesia, total intravenous anesthesia using propofol-sufentanil, higher age, and longer duration of anesthesia were associated with PACU delirium. Based on these findings, adverse effects on postoperative recovery and delirium signs do not have to be considered in the choice of surgical approach for radical prostatectomy.

TRIAL REGISTRATION

https://www.drks.de/, identifier: DRKS00010014.

Inadequate emergence after non-cardiac surgery-A prospective observational study in 1000 patients

INTRODUCTION

The post-anaesthetic phase is most often uncomplicated, but patients may experience inadequate emergence (IE) characterized by unrest, restlessness, aggressiveness or in contrast sedation or lack of initiative. This may increase length of stay (LOS) and post-operative complications. The aim of this study was to investigate frequency, risk factors and consequences of IE.

METHODS

We conducted an observational cohort study including 1000 orthopaedic and abdominal surgical patients, screened with the Nursing Delirium Screening Scale (Nu-DESC) before induction of anaesthesia, at arrival at the post-operative care unit, and just before discharge from PACU. IE was defined as a Nu-DESC score ≥2 after surgery. Predictors included surgical procedure, type and duration of anaesthesia, age, ASA-score, sex and post-operative pain. Data were analysed during adjusted logistic regression and Wilcoxon rank sum test, the primary outcome being LOS.

RESULTS

IE occurred in 103 of 1000 patients (10.3%, 95% CI 8.6-12.3%). LOS was median 2 vs 1 day in patients with and without IE, mean difference was 1.3 (SD 6.2) days (P = 0.036). Thirty-day mortality was 2.9 vs 1.0% (P = 0.92) and admission to ICU 1.0 vs 0.9% (P = 0.66) in patients with and without IE. Significant associations to IE were found for inhalational anaesthetics (OR 2.65; 95% CI: 1.57-4.46), duration of anaesthesia ≥2 hours (OR 1.98; 95% CI: 1.14-3.44) and ASA-score ≥3 (OR 2.74; 95% CI: 1.64-4.57).

CONCLUSION

One of 10 patients had IE as defined by the Nu-DESC score, which was significantly associated with increased LOS. Longer duration of anaesthesia, inhalational anaesthesia and ASA ≥3 were significantly associated to this.

Quality of recovery in elderly patients with postoperative delirium

Background:

Our study aimed to evaluate quality of recovery in elderly patients with postoperative delirium (POD).

Subjects and Methods:

An observational prospective study was conducted. Patients aged >60 submitted to elective surgery and admitted to Post Anesthesia Care Unit (PACU) in a tertiary hospital from May to July 2017 were included. POD was evaluated with the Nursing Delirium Screening Scale (NuDESC). Quality of recovery-15 (QoR-15) was used before (T0) and 24 h (T24) after surgery to assess quality of recovery. Data collection include patient's characteristics, respiratory events at the PACU, and other perioperative variables. The Chi-square, Fisher's exact, or Mann–Whitney U-tests were used for comparisons.

Results:

Of a total of 235 patients, 12.3% developed POD at PACU. POD was more frequently in patients older than 80 years (P = 0.017), patients with neurological disease (P = 0.026), dementia (P = 0.026), peripheral vascular disease (P = 0.016), and diabetes mellitus (P = 0.037). At T0, there were no differences at median total QoR-15, whereas at T24, patients POD scored lower in 10 items (including “severe pain” with P = 0.001 and “nausea or vomiting” with P = 0.009) of QoR-15 and in total median lower scores (P = 0.001). POD patients stayed longer at PACU (P = 0.017) and they stayed longer at hospital (P = 0.002).

Conclusions:

POD patients were older and had more comorbidities. POD patients had lower QoR scores at T24 suggesting an adverse impact of delirium in postoperative quality of recovery. POD patients stayed for long in the PACU and at hospital.

Association of electroencephalogram trajectories during emergence from anaesthesia with delirium in the postanaesthesia care unit: an early sign of postoperative complications

BACKGROUND

Postoperative delirium is associated with an increased risk of morbidity and mortality, especially in the elderly. Delirium in the postanaesthesia care unit (PACU) could predict adverse clinical outcomes.

METHODS

We investigated a potential link between intraoperative EEG patterns and PACU delirium as well as an association of PACU delirium with perioperative outcomes, readmission and length of hospital stay. The risk factors for PACU delirium were also explored. Data were collected from 626 patients receiving general anaesthesia for procedures that would not interfere with frontal EEG recording.

RESULTS

Of the 626 subjects enrolled, 125 tested positive for PACU delirium. Whilst age, renal failure, and pre-existing neurological disease were associated with PACU delirium in the univariable analysis, the multivariable analysis revealed the importance of information derived from the EEG, anaesthetic technique, anaesthesia duration, and history of stroke or neurodegenerative disease. The occurrence of EEG burst suppression during maintenance [odds ratio (OR)=1.86 (1.13-3.05)] and the type of EEG emergence trajectory may be predictive of PACU delirium. Specifically, EEG emergence trajectories lacking significant spindle power were strongly associated with PACU delirium, especially in cases that involved ketamine or nitrous oxide [OR=6.51 (3.00-14.12)]. Additionally, subjects with PACU delirium were at an increased risk for readmission [OR=2.17 (1.13-4.17)] and twice as likely to stay >6 days in the hospital.

CONCLUSIONS

Specific EEG patterns were associated with PACU delirium. These findings provide valuable information regarding how the brain reacts to surgery and anaesthesia that may lead to strategies to predict PACU delirium and identify key areas of investigation for its prevention.

Postoperative delirium

Delirium can be defined as an ‘acute brain dysfunction.’ Compared to dementia, which is a disease that deteriorates the brain function chronically, delirium shows very similar symptoms but is mostly ameliorated when the causative factors are normalized. Due to the heterogeneity in etiologies and symptoms, people including health care workers often mistake delirium for dementia or other psychiatric disorders. Delirium has attracted global interest increasingly and a vast amount of research on its management has been conducted. Experts in the field have constantly suggested that systematic intervention should be implemented through a team-based multicomponent approach aimed to reduce the incidence and duration of delirium. Surgery involves many health care workers with different expertise who are not familiar with delirium. For a team-based approach on the management of delirium, it is vital that all medical personnel concerned have a common understanding of delirium and keep in constant communication. Postoperative delirium is a common complication and exerts an enormous burden on patients, their families, hospitals, and public resources. To alleviate this burden, this article aimed to review general features and the latest evidence-based knowledge of delirium with a focus on postoperative delirium.

An update on postoperative delirium: Clinical features, neuropathogenesis, and perioperative management

PURPOSE OF REVIEW

We present a focused review on postoperative delirium for anesthesiologists, encompassing clinical features, neuropathogenesis, and clinical identification and management strategies based on risk factors and current delirium treatments.

RECENT FINDINGS

The literature on postoperative delirium is dominated by non-experimental studies. We review delirium phenotypes, diagnostic criteria, and present standard nomenclature based on current literature. Disruption of cortical integration of complex information (CICI) may provide a framework to understand the neuropathogenesis of postoperative delirium, as well as risk factors and clinical modifiers in the perioperative period. We further divide risk factors into patient factors, surgical factors, and medical/pharmacological factors, and present specific considerations for each in the preoperative, intraoperative, and postoperative periods.

SUMMARY

Postoperative delirium is prevalent, poorly understood, and often missed with current screening techniques. Proper identification of risk factors is useful for perioperative interventions and can help tailor patient-specific management strategies.

Correlation between duration of preoperative fasting and emergence delirium in pediatric patients undergoing ophthalmic examination under anesthesia: A prospective observational study

BACKGROUND

Preoperative fasting in children can cause anxiety, which may ultimately lead to postoperative emergence delirium. However, no data are available whether duration of preoperative fasting correlates with postoperative emergence delirium.

AIMS

The aim of this study was to identify if there is any correlation between the duration of preoperative fasting and emergence delirium in children undergoing ophthalmic examination under anesthesia.

METHODS

In this prospective observational study, 100 children between the age group 2-6 years of American Society of Anesthesiologists physical status I or II, scheduled for examination of the eye under general anesthesia with sevoflurane were recruited. Data regarding preoperative fasting was recorded and presence of emergence delirium was assessed by the Pediatric Anesthesia Emergence Delirium (PAED) scale at 5 minute interval till 30 minutes from the time of leaving the operation theater. No premedication was used in any patients but parental presence was allowed in all of them.

RESULTS

Mean (standard deviation) duration of fasting to clear liquid was 6.3 (1.7) hrs. Twenty-four children (24%) had at least 1 recorded PAED score >10 at any time point in the postoperative period. PAED scores at 15 and 25 minutes were significantly correlated with duration of fasting (r² [95% CI] = .24 [0.04, 0.41], P = .02, Pearsons's correlation and r² [95% CI] = .23 [0.04, 0.41], P = .02, Pearsons's correlation, respectively). No correlation has been found between duration of fasting and blood glucose level (r² [95% CI] = -.05 [-0.24, 0.15], P = .65, Pearsons's correlation) between fasting blood glucose and PAED score at any time point.

CONCLUSION

Increased preoperative fasting duration may be a risk factor for postoperative emergence delirium in children undergoing ophthalmic examination under general anesthesia.

Impact of timing and duration of postoperative delirium: a retrospective observational study

BACKGROUND

Recent reports suggest that not all critically ill patients with delirium share the same consequences. The outcomes of surgical intensive care unit patients with postoperative delirium were evaluated depending on the onset and duration of delirium.

METHODS

A total of 527 patients who were admitted from the operating theater and cared for in the surgical intensive care unit for >24 hours were evaluated for delirium using the Confusion Assessment Method for intensive care unit, 3 times a day. Patients were analyzed according to the onset time and duration of delirium. Patients were classified into 4 groups according to the onset and duration of delirium: no delirium, early brief delirium (delirium for <1 day on postoperative day 0), late brief delirium (delirium for <1 day after postoperative day 0), and persistent delirium (delirium for ≥1 days). Duration of stay (intensive care unit and hospital) and mortality (intensive care unit, hospital, and 1-year) were outcomes of interest.

RESULTS

Of the 527 patients, delirium developed in 119 (22.6%) patients. More than two-thirds of the patients developed delirium on postoperative day 0 or 1, and 70% of patients developed delirium for >24 hours (persistent). Persistent delirium was associated with longer intensive care unit (4.6 [1.1-53.3] vs 1.6 [1.1-37.5] days) and hospital duration of stay (24 [3-112] vs 16 [2-225] days) and higher hospital mortality (14.5% vs 2.2%) compared to no delirium (P < .01).

CONCLUSION

For postoperative intensive care unit patients, intensive care unit and hospital duration of stay did not seem to differ between patients with early brief delirium or no delirium, whereas patients with late brief or persistent delirium seemed to show longer intensive care unit and hospital duration of stay and higher mortality.

A study into perioperative anaesthetic adverse events in Thailand (PAAd THAI): An analysis of suspected emergence delirium

The purpose of this study is to demonstrate the characteristics, contributing factors and recommended policy changes associated with emergence delirium. Relevant data were extracted from the PAAd Thai database of 2,006 incident reports which were conducted from 1 January to 31 December 2015. Details pertinent to the patient, surgery, anaesthetic and systematic factors were reviewed independently. Seventeen incidents of emergence delirium were recorded. Emergence delirium was common in the following categories: male (70.6%), over 65 years of age (53%), elective surgery (76%) and orthopedic surgery (35%). Physical restraint was required in 53% (9 of 17) of cases and 14 patients (82%) required medical treatment. One patient developed postoperative delirium and required medical treatment. The study led to the following recommendations: Development of a classification of practice guidelines and a screening tool, and training for restraint use.

Infrared pupillometry helps to detect and predict delirium in the post-anesthesia care unit

This study evaluates the capability of pupillary parameters to detect and predict delirium in the post-anesthesia care unit (PACU-D) following general anesthesia. PACU-D may complicate and prolong the patient's postoperative course, consequently increasing hospital costs. After institutional approval, 47 patients undergoing surgical interventions with general anesthesia were included in the study. We measured the pupillary reflexes at signing of informed consent, during surgery 20 min after intubation and when the primary inhaled anesthetic was turned off, and 15 and 45 min after PACU admittance and upon discharge from the PACU. We evaluated patients for delirium using the confusion assessment method for the intensive care unit (CAM-ICU) score after 15 and 60 min in the PACU. We chose receiver operating curve (ROC) and area under the curve (AUC) to compare the performance of non-pupillary parameters to pupillary parameters, such as pupil diameter, percent constriction, and dilation velocity, to detect and predict PACU-D. Percent constriction (AUC = 0.93, optimal threshold = 18.5%) and dilation velocity (AUC = 0.93, optimal threshold = 0.35 mm/s) showed excellent ability to detect and predict delirium persisting throughout the PACU stay. These pupillary measures showed superior performance compared to other pupillary measures and features commonly associated with delirium, e.g., age (AUC = 0.73), total opioids (AUC = 0.56), or length of surgery (AUC = 0.40). Our results suggest that pupillometry and the parameters derived from the recording may identify delirious patients in the PACU. This information can help to efficiently structure their care in a timely manner, and potentially avoid adverse complications for the patient and financial consequences for the hospital.