Delirium detection methodologies: Implications for outcome measurement in clinical trials in postoperative delirium.

OBJECTIVE: Delirium is a common postoperative complication of hip fracture. Various methods exist to detect delirium as a reference standard. The goal of this study was to characterize the properties of the measures obtained in a randomized controlled trial, to document their relationship to the Diagnostic and Statistical Manual of Mental Disorders:Text Revision based diagnosis of postoperative delirium by a consensus panel, and to describe the method in detail to allow replication by others. METHODS: A secondary analysis of the randomized trial STRIDE (A Strategy to Reduce the Incidence of Postoperative Delirium in Elderly Patients) was conducted. Delirium assessments were performed in 200 consecutive hip fracture repair patients ≥65 years old. Assessors underwent extensive training in delirium assessment and the final delirium diagnosis was adjudicated by a consensus panel of three physicians with expertise in delirium assessment. RESULTS: A total of 680 consensus panel delirium diagnoses were completed. There were only 19 (2.8%, 19/678) evaluations where the delirium adjudication by the consensus panel differed from delirium findings by the Confusion Assessment Method (CAM). In 16 (84%, 16/19) of the cases, CAM was negative but the consensus panel diagnosed the patient as having delirium based on all of the available information including the CAM. CONCLUSION: The consensus panel diagnosis was more sensitive compared to CAM alone, however the magnitude of the difference was not large. When assessors are well trained and delirium assessments are closely supervised throughout the study, CAM may be adequate for delirium diagnosis in a clinical trial. Future studies are needed to test this hypothesis.

Processed intraoperative burst suppression and postoperative cognitive dysfunction in a cohort of older noncardiac surgery patients.

Postoperative cognitive dysfunction (POCD) is a decline in cognitive test performance which persists months after surgery. There has been great interest in the anesthesia community regarding whether variables generated by commercially available processed EEG monitors originally marketed to prevent awareness under anesthesia can be used to guide intraoperative anesthetic management to prevent POCD. Processed EEG monitors represent an opportunity for anesthesiologists to directly monitor the brain even if they have not been trained to interpret EEG waveforms. There is continued equipoise regarding whether any of the variables generated by the machines' interpretation of raw data are associated with POCD. Most literature has focused on the depth of anesthesia number, however recent studies have shown that processed depth may not be accurate in older age groups due to reduced alpha band power. Burst suppression is an encephalographic pattern of high voltage activity alternating with periods of electrical silence and is another marker of depth which can be obtained from commercial processed EEG monitors. We performed a prospective cohort study to determine whether burst suppression and burst suppression ratio as measured by the BIS Monitor (Bispectral Index, BIS Medtronic, Boulder CO), is associated with cognitive dysfunction 3 months after surgery. We recruited 167 elective surgery patients, 65 years of age and older, anticipated to require at least 2 day inpatient admission. Our main outcome measure was cognitive decline in composite z-score on the Alzheimer's Disease Research Center UDS Battery of at least 1 standard deviation 3 months after surgery relative to preoperative baseline. 14% experienced POCD, this group was older (72 [70, 74] versus 70 [67, 75] years), and had frailty scores as measured by the FRAIL Scale (2 [0, 3] versus 1 [0, 2]) and lower baseline z-scores (- 0.2 [- 0.6, 0.5] versus 0.1 [- 0.3, 0.5]). There was a univariable association between suppression ratio > 10 (SR > 10) and POCD (4.8 [0, 37.3] versus 15.4 [4.0-142.4] min), p = .038. However, after adjustment this relationship did not persist, only anesthetic technique, age, and pain remained in the model. In our cohort of older elective noncardiac surgery patients we found a marginal association between processed burst suppression (total burst suppression p = .067, SR > 5 p = .052, SR > 10.038) which did not persist in a multivariable model. Patients with POCD had almost twice the number of minutes of burst suppression, and three times the amount of time for SR > 5 and > 10. Our finding may be a limitation of the monitor's ability to detect burst suppression. The consistent trend towards more intraoperative burst suppression in patients who developed POCD suggests that future studies are needed to investigate the relationship of raw intraoperative burst suppression and POCD.Trial registry Clinical trial number and registry URL: Optimizing Postoperative Cognitive Dysfunction in the Elderly-PRESERVE, Clinical Trials Gov# NCT02650687; https://clinicaltrials.gov/ct2/show/NCT02650687 .

Effects of Ramelteon on the Prevention of Postoperative Delirium in Older Patients Undergoing Orthopedic Surgery: The RECOVER Randomized Controlled Trial.

OBJECTIVES: Postoperative delirium, associated with negative consequences including longer hospital stays and worse cognitive and physical outcomes, is frequently accompanied by sleep-wake disturbance. Our objective was to evaluate the efficacy and short-term safety of ramelteon, a melatonin receptor agonist, for the prevention of postoperative delirium in older patients undergoing orthopedic surgery. DESIGN: A quadruple-masked randomized placebo-controlled trial (Clinical Trials.gov NCT02324153) conducted from March 2017 to June 2019. SETTING: Tertiary academic medical center. PARTICIPANTS: Patients aged 65 years or older, undergoing elective primary or revision hip or knee replacement. INTERVENTION: Ramelteon (8 mg) or placebo MEASUREMENTS: Eighty participants were randomized to an oral gel cap of ramelteon or placebo for 3 consecutive nights starting the night before surgery. Trained research staff conducted delirium assessments for 3 consecutive days starting on postoperative day (POD) 0, after recovery from anesthesia, and on to POD2. A delirium diagnosis was based upon DSM-5 criteria determined by expert panel consensus. RESULTS: Of 80 participants, five withdrew consent (one placebo, four ramelteon) and four were excluded (four ramelteon) after randomization. Delirium incidence during the 2 days following surgery was 7% (5 of 71) with no difference between the ramelteon versus placebo: 9% (3 of 33) and 5% (2 of 38), respectively. The adjusted odds ratio for postoperative delirium as a function of assignment to the ramelteon treatment arm was 1.28 (95% confidence interval: 0.21-7.93; z-value 0.27; p-value = 0.79). Adverse events were similar between the two groups. CONCLUSION: In older patients undergoing elective primary or revision hip or knee replacement, ramelteon was not efficacious in preventing postoperative delirium.

Association of Depressive Symptoms With Postoperative Delirium and CSF Biomarkers for Alzheimer's Disease Among Hip Fracture Patients.

OBJECTIVES: While there is growing evidence of an association between depressive symptoms and postoperative delirium, the underlying pathophysiological mechanisms remain unknown. The goal of this study was to explore the association between depression and postoperative delirium in hip fracture patients, and to examine Alzheimer's disease (AD) pathology as a potential underlying mechanism linking depressive symptoms and delirium. METHODS: Patients 65 years old or older (N = 199) who were undergoing hip fracture repair and enrolled in the study "A Strategy to Reduce the Incidence of Postoperative Delirium in Elderly Patients" completed the 15-item Geriatric Depression Scale (GDS-15) preoperatively. Cerebrospinal fluid (CSF) was obtained during spinal anesthesia and assayed for amyloid-beta (Aß) 40, 42, total tau (t-tau), and phosphorylated tau (p-tau)181. RESULTS: For every one point increase in GDS-15, there was a 13% increase in odds of postoperative delirium, adjusted for baseline cognition (MMSE), age, sex, race, education and CSF AD biomarkers (OR = 1.13, 95%CI = 1.02-1.25). Both CSF Aß42/t-tau (ß = -1.52, 95%CI = -2.1 to -0.05) and Aß42/p-tau181 (ß = -0.29, 95%CI = -0.48 to -0.09) were inversely associated with higher GDS-15 scores, where lower ratios indicate greater AD pathology. In an analysis to identify the strongest predictors of delirium out of 18 variables, GDS-15 had the highest classification accuracy for postoperative delirium and was a stronger predictor of delirium than both cognition and AD biomarkers. CONCLUSIONS: In older adults undergoing hip fracture repair, depressive symptoms were associated with underlying AD pathology and postoperative delirium. Mild baseline depressive symptoms were the strongest predictor of postoperative delirium, and may represent a dementia prodrome.

The Association of Preoperative Frailty and Postoperative Delirium: A Meta-analysis.

BACKGROUND: Both frailty and postoperative delirium (POD) are common in elective surgical patients 65 years of age and older. However, the association between preoperative frailty and POD remains difficult to characterize owing to the large number of frailty and POD assessment tools used in the literature, only a few of which are validated. Furthermore, some validated frailty tools fail to provide clear score cutoffs for distinguishing frail and nonfrail patients. We performed a meta-analysis to estimate the relationship between preoperative frailty and POD. METHODS: We searched several major databases for articles that investigated the relationship between preoperative frailty and POD in patients with mean age ≥65 years who were undergoing elective, nonemergent inpatient surgery. Inclusion criteria included articles published in English no earlier than 1999. Both preoperative frailty and POD must have been measured with validated tools using clear cutoff scores for frailty and delirium. Articles were selected and data extracted independently by 2 researchers. Risk of bias (ROBINS-I) and presence of confounders were summarized. Odds ratios (ORs) for POD associated with frailty relative to nonfrailty were computed with adjusted ORs when available. Original estimates were pooled by random effects analysis. Statistical significance was set at 2-sided P < .05. RESULTS: Nine studies qualified for meta-analysis. The Fried score or a modified version of it was used in 5 studies. Frailty prevalence ranged from 18.6% to 56%. Delirium was assessed with the Confusion Assessment Method (CAM) or Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) in 7 studies, Delirium Observation Scale in 1 study, and Intensive Care Delirium Screening Checklist in 1 study. The incidence of POD ranged from 7% to 56%. ROBINS-I risk of bias was low in 1 study, moderate in 4 studies, serious in 3 studies, and critical in 1 study. Random effects analysis (n = 794) of the OR for POD in frail versus nonfrail patients based on adjusted OR estimates was significant with an OR of 2.14 and a 95% confidence interval of 1.43-3.19. The I2 value was in the low range at 5.5, suggesting small variability from random effects. Funnel-plot analysis did not definitively support either the presence or absence of publication bias. CONCLUSIONS: This meta-analysis provides evidence for a significant association between preoperative frailty and POD in elective surgical patients age 65 years or older.

Preoperative Evaluation of the Frail Patient.

Perioperative management of older adults is a complex field that is heavily influenced by the clinical heterogeneity of older adults. Frailty-a geriatric syndrome in which a patient is more vulnerable to stressors due to decreases in physical function and reserve-has been indicative of adverse postoperative outcomes. Many tools have been developed to measure frailty that incorporate a variety of factors including physical and cognitive function, comorbidities, self-reported measures of health, and clinical judgment. Most of these frailty assessment tools are able to identify a subset of patients at risk of adverse outcomes including postoperative complications, longer hospital length of stay, discharge to a higher level of care, and mortality. Frailty assessment before surgical interventions can also guide discussions among patients, their families, anesthesiologists, and surgeons to tailor operative plans for patients to mitigate this increased risk. Studies are ongoing to identify interventions in frail patients that can improve postoperative outcomes, but high-quality data in the form of randomized controlled trials are lacking at this time.

Frailty Is Associated With Postoperative Delirium But Not With Postoperative Cognitive Decline in Older Noncardiac Surgery Patients.

BACKGROUND: Postoperative cognitive dysfunction (POCD) and delirium are the most common perioperative cognitive complications in older adults undergoing surgery. A recent study of cardiac surgery patients suggests that physical frailty is a risk factor for both complications. We sought to examine the relationship between preoperative frailty and postoperative delirium and preoperative frailty and POCD after major noncardiac surgery. METHODS: We performed a prospective cohort study of patients >65 years old having major elective noncardiac surgery with general anesthesia. Exclusion criteria were preexisting dementia, inability to consent, cardiac, intracranial, or emergency surgery. Preoperative frailty was determined using the FRAIL scale, a simple questionnaire that categorizes patients as robust, prefrail, or frail. Delirium was assessed with the Confusion Assessment Method for the intensive care unit (CAM-ICU) twice daily, starting in the recovery room until hospital discharge. All patients were assessed with neuropsychological tests (California Verbal Learning Test II, Trail Making Test, subtests from the Wechsler Adult Intelligence Scale, Logical Memory Story A, Immediate and Delayed Recall, Animal and Vegetable verbal fluency, Boston Naming Test, and the Mini-Mental Status Examination) before surgery and at 3 months afterward. RESULTS: A total of 178 patients met inclusion criteria; 167 underwent major surgery and 150 were available for follow-up 3 months after surgery. The median age was 70 years old. Thirty-one patients (18.6%) tested as frail, and 72 (43.1%) prefrail before surgery. After adjustment for baseline cognitive score, age, education, surgery duration, American Society of Anesthesiologists (ASA) physical status, type of surgery, and sex, patients who tested frail or prefrail had an estimated 2.7 times the odds of delirium (97.5% confidence interval, 1.0-7.3) when compared to patients who were robust. There was no significant difference between the proportion of POCD between patients who tested as frail, prefrail, or robust. CONCLUSIONS: After adjustment for baseline cognition, testing as frail or prefrail with the FRAIL scale is associated with increased odds of postoperative delirium, but not POCD after noncardiac surgery.

Shaping anesthetic techniques to reduce post-operative delirium (SHARP) study: a protocol for a prospective pragmatic randomized controlled trial to evaluate spinal anesthesia with targeted sedation compared with general anesthesia in older adults undergoing lumbar spine fusion surgery.

BACKGROUND: Postoperative delirium is common in older adults, especially in those patients undergoing spine surgery, in whom it is estimated to occur in > 30% of patients. Although previously thought to be transient, it is now recognized that delirium is associated with both short- and long-term complications. Optimizing the depth of anesthesia may represent a modifiable strategy for delirium prevention. However, previous studies have generally not focused on reducing the depth of anesthesia beyond levels consistent with general anesthesia. Additionally, the results of prior studies have been conflicting. The primary aim of this study is to determine whether reduced depth of anesthesia using spinal anesthesia reduces the incidence of delirium after lumbar fusion surgery compared with general anesthesia. METHODS: This single-center randomized controlled trial is enrolling 218 older adults undergoing lumbar fusion surgery. Patients are randomized to reduced depth of anesthesia in the context of spinal anesthesia with targeted sedation using processed electroencephalogram monitoring versus general anesthesia without processed electroencephalogram monitoring. All patients are evaluated for delirium using the Confusion Assessment Method for 3 days after surgery or until discharge and undergo assessments of cognition, function, health-related quality of life, and pain at 3- and 12-months after surgery. The primary outcome is any occurrence of delirium. The main secondary outcome is change in the Mini-Mental Status Examination (or telephone equivalent) at 3-months after surgery. DISCUSSION: Delirium is an important complication after surgery in older adults. The results of this study will examine whether reduced depth of anesthesia using spinal anesthesia with targeted depth of sedation represents a modifiable intervention to reduce the incidence of delirium and other long-term outcomes. The results of this study will be presented at national meetings and published in peer-reviewed journals with the goal of improving perioperative outcomes for older adults. TRIAL REGISTRATION: Clinicaltrials.gov , NCT03133845. This study was submitted to Clinicaltrials.gov on October 23, 2015; however, it was not formally registered until April 28, 2017 due to formatting requirements from the registry, so the formal registration is retrospective.

Impact of Delirium After Hip Fracture Surgery on One-Year Mortality in Patients With or Without Dementia: A Case of Effect Modification.

OBJECTIVES: We evaluated whether delirium after hip fracture repair modifies the relationship between baseline dementia and one-year mortality after surgery. METHODS: Patients age 65 years and older undergoing hip fracture repair surgery at John Hopkins Bayview Medical Center between 1999 and 2009 were eligible for this prospective cohort study. Baseline probable dementia was defined as either preoperatively diagnosed dementia per geriatrician or score less than 24 on the Mini-Mental State Examination. Delirium was assessed using the Confusion Assessment Method. Four cognitive groups were defined: 1) neither probable dementia nor delirium (NDD), 2) probable dementia only, 3) delirium only, or 4) delirium superimposed on dementia (DSD). Primary outcome of mortality was obtained through hospital records, obituaries, the National Death Index, and Social Security Death Index. RESULTS: The current sample comprises 466 subjects (average age: 80.8 ± 7.0 years; 73.6% female). Of these, 77 (17%) were categorized as DSD, 68 (15%) probable dementia only, 73 (16%) delirium only, and 248 (53%) NDD. Cox regression revealed that DSD subjects had a significantly higher hazard of one-year mortality than NDD subjects (hazard ratio [HR]: 1.71, 95% CI: 1.06, 2.77) after adjusting for age, sex, medical comorbidity, and surgery duration. Trends toward greater mortality for probable-dementia and delirium only subjects were not significant (HR: 1.42 [95% CI: 0.80, 2.52] and 1.12 [95% CI: 0.64, 1.95], respectively). CONCLUSIONS: Delirium after hip fracture repair surgery in patients with preoperative dementia modifies the risk of mortality over the first postoperative year. Patients with DSD have a nearly two-fold greater odds of one-year mortality than those without dementia or delirium.

Design considerations of a randomized controlled trial of sedation level during hip fracture repair surgery: a strategy to reduce the incidence of postoperative delirium in elderly patients.

Background Delirium is an acute change in mental status characterized by sudden onset, fluctuating course, inattention, disorganized thinking, and abnormal level of consciousness. The objective of the randomized controlled trial "A STrategy to Reduce the Incidence of Postoperative Delirium in Elderly Patients" (STRIDE) is to assess the effectiveness of light versus heavy sedation on delirium and other outcomes in elderly patients undergoing hip fracture repair surgery. Our goal is to describe the design considerations and lessons learned in planning and implementing the STRIDE trial. Methods Discussed are challenges encountered including (1) how to ensure that we quickly identify, assess the eligibility of, and randomize traumatic hip fracture patients; (2) how to implement interventions that involve continuous monitoring and adjustment during the surgery; and (3) how to measure and ascertain the primary outcome, delirium. Results To address the first challenge, we monitored the operating room schedule more actively than anticipated. We constructed and organized eligibility assessment data collection forms by purpose and by source of information needed to complete them. We decided that randomization needs to take place in the operating room. To address the second challenge, we designed and implemented a treatment protocol and covered the bispectral index monitor to prevent the Anesthesiologist/Anesthetist from being influenced by the bispectral index reading while administering the intervention. Finally, clinical assessment of delirium consisted of standardized interviews of the patient using validated instruments, interviews of those caring for the patient, and review of the medical record. A consensus panel made the final determination of a delirium diagnosis. We note that STRIDE is a single-center trial. The decisions we took may have different implications for multi-center trials. Conclusions Lessons learned are likely to provide useful information to others designing trials in emergency and surgical setting and for those who are interested in unbiased assessment of delirium.

Long-Term Outcomes of Older Adults with and Without Delirium Immediately After Recovery from General Anesthesia for Surgery.

OBJECTIVE: Postoperative delirium, occurring days after surgery, is associated with both short- and long-term adverse events. Postanesthesia care unit (PACU) delirium, immediately after recovery from anesthesia, is associated with continued delirium in the succeeding days and adverse cognitive outcomes at discharge. Longer-term consequences are unclear. The objective was to evaluate 18-month outcomes of patients with versus without delirium in the PACU after surgery with general anesthesia. METHODS: In a prospective, observational, cohort study, 91 consecutive English-speaking patients, aged at least 70 years and capable of independently providing informed consent before surgery, were followed after admission for a surgical procedure in one teaching hospital. Patients completed cognitive testing before surgery. After recovery from general anesthesia, they were evaluated for a DSM-IV diagnosis of delirium. Participants or proxies were evaluated, at a median of 19 months after surgery (interquartile range: 18-20 months), for survival, cognitive and physical functioning, and healthcare utilization outcomes. RESULTS: All 91 patients or proxies (41 with delirium [45%]) were contacted at follow-up, with 7 deaths (8%) and 3 declining further participation (3%); 81 (96% of survivors) completed follow-up evaluations, demonstrating no significant cognitive or functional decline from baseline, with 75% of the cohort living independently in the community, and no differences in any outcomes between patients with versus without PACU delirium. CONCLUSION: In a small cohort of older patients evaluated 18 months after surgery, we could not detect an association of delirium diagnosed in the PACU with patient survival, cognitive/physical functioning, and healthcare utilization.

Preoperative risk factors for postoperative delirium following hip fracture repair: a systematic review.

OBJECTIVE: Systematically identify preoperative clinical risk factors for incident postoperative delirium in individuals undergoing hip fracture repair in order to guide clinicians in identifying high risk patients at admission. METHODS: This is a systematic review of prospective observational studies with estimation of association between preoperative risk factors and incident postoperative delirium in multivariate models. Electronic searches were conducted in PubMed, Embase, PsycINFO, CINAHL, Cochrane Library, Proquest Dissertations and Theses, and WorldCatDissertations. Hand searches were conducted in selected journals and their supplements. RESULTS: Search yielded 6380 titles and abstracts from electronic databases and 72 titles from hand searches, and 10 studies met inclusion criteria. The following risk factors were significant in bivariate models: cognitive impairment, age, gender, institutionalization, functional impairment, body mass index (BMI), albumin, comorbidities, American Society of Anesthesiologist classification, acute medical conditions, polypharmacy, and vision impairment. Among all of these risk factors, cognitive impairment most consistently remained statistically significant after adjusting for other risk factors in multivariate models, followed by BMI/albumin and multiple comorbidities. CONCLUSION: In our systematic review, cognitive impairment was one of the strongest preoperative risk factors for postoperative delirium after hip fracture surgery. Preoperative cognitive assessment may be one of the most useful methods of identifying those who are at high risk for postoperative delirium and prioritizing delivery of delirium prevention measures.

The Impact of Incident Postoperative Delirium on Survival of Elderly Patients After Surgery for Hip Fracture Repair.

BACKGROUND: The impact of delirium on survival of elderly patients remains undetermined with conflicting results from clinical studies and meta-analysis. In this study, we assessed the relationship between long-term mortality and incident postoperative delirium in elderly patients undergoing hip fracture repair. METHODS: Patients ≥65 years old who were not delirious before undergoing hip fracture repair were included in a database maintained prospectively from March 1999 to July 2009. All participating patients underwent delirium assessment on the second postoperative day by using the confusion assessment method. Survival of the participants was determined as of October 2012. RESULTS: In 459 patients, the mean (SD) period of evaluation from surgery until death or study closure was 4.1 (3.5) years with patients followed for as long as 13.6 years. Preoperative cognitive impairment was present in 120 patients (26.1%), and delirium on the second postoperative day was observed in 151 (32.9%) of these patients. Although univariate analysis demonstrated a strong association between incident postoperative delirium and survival, this relationship did not persist in a multivariate model. Survival was a function of age at the time of surgery (P < 0.001), illness severity as determined by the ASA physical status score (P < 0.001), and duration of admission to the intensive care unit after surgery (P < 0.001). Incorporation of incident postoperative delirium did not meaningfully (P = 0.22) enhance the final survival model. In such a model, the hazard ratio (95% confidence interval) for incident postoperative delirium was 1.25 (0.92-1.48). CONCLUSIONS: Incident postoperative delirium was not significantly associated with decreased survival in elderly patients undergoing hip fracture repair.

Sedation depth during spinal anesthesia and survival in elderly patients undergoing hip fracture repair.

Low intraoperative Bispectral Index (BIS) values may be associated with increased mortality. In a previously reported trial to prevent delirium, we randomized patients undergoing hip fracture repair under spinal anesthesia to light (BIS >80) or deep (BIS approximately 50) sedation. We analyzed survival of patients in the original trial. Among all patients, mortality was equivalent across sedation groups. However, among patients with serious comorbidities (Charlson score >4), 1-year mortality was reduced in the light (22.2%) vs deep (43.6%) sedation group (hazard ratio [HR], 0.43; 95% confidence interval, 0.19-0.97; P = 0.04) during spinal anesthesia. Similarly, among patients with Charlson score >6, 1-year mortality was reduced in the light (28.6%) vs deep (52.6%) sedation group (HR 0.33; 95% confidence interval, 0.12-0.94; P = 0.04) during spinal anesthesia. Further research on reduced mortality after light sedation during spinal anesthesia is needed.

Outcomes of early delirium diagnosis after general anesthesia in the elderly.

BACKGROUND: Postoperative delirium in the elderly, measured days after surgery, is associated with significant negative clinical outcomes. In this study, we evaluated the prevalence and in-hospital outcomes of delirium diagnosed immediately after general anesthesia and surgery in elderly patients. METHODS: Consecutive English-speaking surgical candidates, aged 70 years or older, were prospectively enrolled during July to August 2010. After surgery, each participant was evaluated for a Diagnostic and Statistical Manual of Mental Disorders IV diagnosis of delirium in the postanesthesia care unit (PACU) and repeatedly thereafter while hospitalized. Delirium in the PACU was evaluated for an independent association with change in cognitive function from preoperative baseline testing and discharge disposition. RESULTS: Ninety-one (58% female) patients, 78% of whom were living independently before surgery, were found to have a prevalence of delirium in the PACU of 45% (41/91); 74% (14/19) of all delirium episodes detected during subsequent hospitalization started in the PACU. Early delirium was independently associated with impaired cognition (i.e., decreased category word fluency) relative to presurgery baseline testing (adjusted difference [95% confidence interval] for change in T-score: -6.02 [-10.58 to -1.45]; P = 0.01). Patients whose delirium had resolved by postoperative day 1 showed negative outcomes that were intermediate in severity between those who were never delirious during hospitalization and those whose delirium in the PACU persisted after transfer to hospital wards (adjusted probability [95% confidence interval] of discharge to institution: 3% [0%-10%], 26% [1%-51%], 39% [0%-81%] for the 3 groups, respectively). CONCLUSIONS: Delirium in the PACU is common, but not universal. It is associated with subsequent delirium on the ward, and potentially with a decline in cognitive function and increased institutionalization at hospital discharge.

Leg Length Discrepancy After Hip Fracture Repair is Associated With Reduced Gait Speed.

Introduction: A negative correlation exists between functional outcomes and leg length discrepancy (LLD) following hip fracture repair. We have assessed the effects of LLD following hip fracture repair in elderly patients on 3-meter walking time, standing time, activities of daily living (ADL), and instrumental activities of daily living (IADL). Methods: One hundred sixty-nine patients enrolled in the STRIDE trial were identified with femoral neck, intertrochanteric, and subtrochanteric fractures that were treated with partial hip replacement, total hip replacement, cannulated screws, or intramedullary nail. Baseline patient characteristics recorded included age, sex, body mass index Charlson comorbidity index (CCI) score. ADL, IADL, grip strength, sit-to-stand time, 3-meter walking time and return to ambulation status were measured at 1 year after surgery. LLD was measured on final follow-up radiographs by either the sliding screw telescoping distance or the difference from a trans-ischial line to the lesser trochanters, and was analyzed as a continuous variable using regression analysis. Results: Eighty eight patients (52%) had LLD <5 mm, 55 (33%) between 5-10 mm and 26 subjects (15%) >10 mm. Age, sex, BMI, Charlson score, and ambulation status had no significant impact on LLD occurrence. Type of procedure and fracture type did not correlate with severity of LLD. Having a larger LLD was not found to have a significant impact on post-operative ADL (P = .60), IADL (P = .08), sit-to-stand time (P = .90), grip strength (P = .14) and return to former ambulation status (P = .60), but did have a statistically significant impact on 3-meter walking time (P = .006). Discussion: LLD after hip fracture was associated with reduced gait speed but did not affect many parameters associated with recovery. Continued efforts to restore leg length after hip fracture repair are likely to be beneficial.

Kidney Function Modifies the Effect of Intraoperative Opioid Dosage on Postoperative Delirium.

BACKGROUND: There are few studies demonstrating how kidney function affects the risk of developing delirium in older adult surgical patients administered opioids. This study determined whether baseline kidney function influences the relationship between morphine equivalent dose and the development of delirium on postoperative day (POD) 2 in patients with hip fracture. METHODS: This retrospective study analyzed emergency department (ED) estimated glomerular filtration rate (eGFR), perioperative serum creatinine, intravenous morphine equivalents, and POD2 delirium assessment by the Confusion Assessment Method in 652 patients aged 65 years or older without preoperative delirium. ED eGFR was used to divide subjects into groups by presence or absence of chronic kidney disease (CKD), and associations of opioid dose with POD2 delirium were compared using multivariable logistic regression. RESULTS: POD2 delirium incidence was 29.8% (N = 194). Intraoperative and postanesthesia care unit (PACU) morphine equivalent dosage as well as ED eGFR were similar comparing patients with and without POD2 delirium. Age, American Society of Anesthesiologists status, and dementia were associated with delirium on POD2. The odds of POD2 delirium increased significantly with increase of intraoperative opioid in patients with CKD (odds ratio = 1.6; 95% confidence interval = 1.2-2.2), but not in patients without CKD (P-interaction = .04). PACU or POD1 opioid doses were not associated with POD2 delirium after covariate adjustment. CONCLUSION: This study suggests that incremental increases in intraoperative opioids combined with CKD increase odds of POD2 delirium after hip fracture repair, compared with patients without CKD.