Lorazepam is an independent risk factor for transitioning to delirium in intensive care unit patients

BACKGROUND: Delirium has recently been shown as a predictor of death, increased cost, and longer duration of stay in ventilated patients. Sedative and analgesic medications relieve anxiety and pain but may contribute to patients' transitioning into delirium. METHODS: In this cohort study, the authors designed a priori an investigation to determine whether sedative and analgesic medications independently increased the probability of daily transition to delirium. Markov regression modeling (adjusting for 11 covariates) was used in the evaluation of 198 mechanically ventilated patients to determine the probability of daily transition to delirium as a function of sedative and analgesic dose administration during the previous 24 h. RESULTS: Lorazepam was an independent risk factor for daily transition to delirium (odds ratio, 1.2 [95% confidence interval, 1.1-1.4]; P = 0.003), whereas fentanyl, morphine, and propofol were associated with higher but not statistically significant odds ratios. Increasing age and Acute Physiology and Chronic Health Evaluation II scores were also independent predictors of transitioning to delirium (multivariable P values < 0.05). CONCLUSIONS: Lorazepam administration is an important and potentially modifiable risk factor for transitioning into delirium even after adjusting for relevant covariates.     

Apolipoprotein E e4 Allele Increases the Risk of Early Postoperative Delirium in Older Patients Undergoing Noncardiac Surgery

Background: Whether patients who subsequently develop early postoperative delirium have a genetic predisposition that renders them at risk for postoperative delirium has not been determined.

Methods: The authors conducted a nested cohort study to include patients aged >= 65 yr who were scheduled to undergo major noncardiac surgery requiring anesthesia. A structured interview was conducted preoperatively and for the first 2 days postoperatively to determine the presence of delirium, defined using the Confusion Assessment Method. Blood was drawn for measurement of the apolipoprotein genotypes. Bivariate tests of association were conducted between delirium and apolipoprotein genotypes and other potentially important risk factors. Variables that had significant bivariate association with postoperative delirium were entered in a forward multivariable logistic regression model.

Results: Of the 190 patients studied, 15.3% developed delirium on both days 1 and 2 after surgery. Forty-six patients (24.2%) had at least one copy of the apolipoprotein e4 allele. The presence of one copy of the e4 allele was associated with an increased risk of early postoperative delirium (28.3% vs. 11.1%; P = 0.005). Even after adjusting for covariates, patients with one copy of the e4 allele were still more likely to have an increased risk of early postoperative delirium (odds ratio, 3.64; 95% confidence interval, 1.51-8.77) compared with those without the e4 allele.     

The correlation of the bispectral index monitor with clinical sedation scores during mechanical ventilation in the pediatric intensive care unit

In patients who are mechanically ventilated in the pediatric intensive care unit (PICU), sedative and/or analgesic medications are routinely provided and titrated to effect based on clinical assessment of the patient. The bispectral index (BIS) monitor uses a modified electroencephalogram to quantify the effects of central nervous system-acting drugs on the level of consciousness. To evaluate the usefulness of the BIS monitor to predict clinical sedation levels in the PICU, we compared BIS values with simultaneously obtained clinical sedation scores in 24 mechanically ventilated pediatric patients aged 5.7 plus minus 6.1 yr. For each sedation scale used, the BIS value correlated with increasing depth of sedation (P < 0.0001) and was independent of the drug(s) used for sedation. To differentiate adequate from inadequate sedation, a BIS value <70 had a sensitivity of 0.87--0.89 and a positive predictive value of 0.68--0.84. To differentiate adequate from excessive sedation, a BIS value <50 had a sensitivity of 0.67--0.75 and a positive predictive value of 0.07--0.52. We conclude that the BIS monitor may be a useful adjunct for the assessment of sedation in PICU patients. IMPLICATIONS: We demonstrate the usefulness of the bispectral index monitor for assessing sedation in pediatric intensive care unit patients. The bispectral index monitor correlated with clinically assessed sedation levels and was useful for differentiating adequate from inadequate sedation, which would be of value when the clinical examination is unavailable.     

Current Practices in Sedation and Analgesia for Mechanically Ventilated Critically Ill Patients: A Prospective Multicenter Patient-based Study

Background: The authors conducted a patient-based survey of practices to fully describe the assessment and the management of pain and sedation of a large cohort of mechanically ventilated patients during their first week of intensive care unit (ICU) stay.

Methods: A total of 1,381 adult patients were included in a prospective, observational study in 44 ICUs in France. Pain and sedation assessment, analgesic and sedative use, and analgesic management during procedural pain were collected on days 2, 4, and 6 of the ICU stay.

Results: The observed rates of assessment on day 2 for sedation (43%) and analgesia (42%) were significantly smaller than that of use of sedatives (72%) and opioids (90%), also noted on days 4 and 6. The use of protocols/guidelines for sedation/analgesia in the ICU reduced the proportion of patients who were treated, although not evaluated. A large proportion of assessed patients were in a deep state of sedation (40-50%). Minor changes in the dosages of the main prescribed agents for sedation (midazolam, propofol) and analgesia (sufentanil, fentanyl, morphine, remifentanil) were found across 6 days of the patient's ICU stay. Procedural pain was specifically managed for less than 25% of patients; during those procedures, the proportion of patients with pain significantly increased from the baseline pain evaluation.     

Brief report: preoperative frailty in older surgical patients is associated with early postoperative delirium

We investigated whether preoperative frailty among older noncardiac surgical patients provides information about the development of postoperative delirium that is in addition to traditional geriatric risk factors. One-third of patients had a frailty score ≥3, which is considered "frail" in others' research. Twenty-five percent of patients developed postoperative delirium, which was measured using the confusion assessment method. Multivariable logistic regression showed that age, activities of daily living dependence, instrumental activities of daily living dependence, and cognitive functioning did not contribute significantly to the prediction of postoperative delirium. Only preoperative symptoms of depression (odds ratio=1.42; 95% confidence interval=1.06-1.91; P=0.018) and the frailty score (odds ratio=1.84; 95% confidence interval=1.07-3.1; P=0.028) were independently associated with the development of postoperative delirium.     

Acupuncture therapy for infants: a preliminary report on reasons for consultation, feasibility, and tolerability

Objectives/aims: The aim of this retrospective review was to determine the feasibility, safety, and potential therapeutic effects of acupuncture in an inpatient infant population and to obtain data that would support the design of a randomized, controlled trial of acupuncture in infants. Background: Hospitalized infants are often exposed to sedative and analgesic medications to facilitate intensive and invasive medical care. With increasing concern about the potential neurotoxic effects of common analgesic and sedative medications, minimizing an infant’s exposure to such agents is desirable. Acupuncture can be therapeutic in adults and children, but data in infants are lacking. Methods/materials: We performed a retrospective chart review of infants who received acupuncture during hospitalizations between 2008 and 2010. Demographic data, diagnoses, reason for acupuncture consult, ventilator settings, sedative/analgesic medication regimens, details of acupuncture therapy, and adverse effects were among data collected. Results: Ten infants were identified in this review, seven of whom had agitation issues, two of whom had feeding difficulties, and one had both symptoms. Six of the eight infants with agitation had a decrease in the use of sedative and analgesic medications over the acupuncture therapy period, and four of five initially requiring mechanical ventilation were successfully weaned. One of the three infants with oral aversion transitioned rapidly to oral intake. Acupuncture therapy was well tolerated, and there were no complications observed. Conclusions: In this small group of hospitalized infants, acupuncture was found to be safe, well tolerated, and therapeutic. More studies are warranted to define the role of acupuncture in this population.     

Apolipoprotein E e4 allele increases the risk of early postoperative delirium in older patients undergoing noncardiac surgery

BACKGROUND: Whether patients who subsequently develop early postoperative delirium have a genetic predisposition that renders them at risk for postoperative delirium has not been determined. METHODS: The authors conducted a nested cohort study to include patients aged > or = 65 yr who were scheduled to undergo major noncardiac surgery requiring anesthesia. A structured interview was conducted preoperatively and for the first 2 days postoperatively to determine the presence of delirium, defined using the Confusion Assessment Method. Blood was drawn for measurement of the apolipoprotein genotypes. Bivariate tests of association were conducted between delirium and apolipoprotein genotypes and other potentially important risk factors. Variables that had significant bivariate association with postoperative delirium were entered in a forward multivariable logistic regression model. RESULTS: Of the 190 patients studied, 15.3% developed delirium on both days 1 and 2 after surgery. Forty-six patients (24.2%) had at least one copy of the apolipoprotein e4 allele. The presence of one copy of the e4 allele was associated with an increased risk of early postoperative delirium (28.3% vs. 11.1%; P = 0.005). Even after adjusting for covariates, patients with one copy of the e4 allele were still more likely to have an increased risk of early postoperative delirium (odds ratio, 3.64; 95% confidence interval, 1.51-8.77) compared with those without the e4 allele. CONCLUSIONS: Apolipoprotein e4 carrier status was associated with an increased risk for early postoperative delirium after controlling for known demographic and clinical risk factors. These results suggest that genetic predisposition plays a role and may interact with anesthetic/surgical factors contributing to the development of early postoperative delirium.     

Dexmedetomidine in intensive care unit: a study of hemodynamic changes

BACKGROUND: Dexmedetomidine is a potent new alpha-2 adrenoceptor agonist with an alpha-2 to alpha- ratio more than 7 times that of clonidine. Its potent sedative, analgesic and sympatholytic effects blunt the cardiovascular responses (hypertension, tachycardia) without unexpected toxicity. Many reports confirmed its pharmacological properties if given by infusion. Recent report confirmed favorable non-depressant effect on respiration and blood gases. SETTING: ICU patients at King Khalid University Hospital. PATIENTS AND METHOD: Open label clinical evaluation on ten surgical patient ASA I class received dexmeditomidine infusion to the sedative effect level of Ramsy scale of 3 for ventilated patients and 2 for spontaneously breathing patient. The clinical observation and analgesic requirement as well as the hemodynamic parameters and hemoglobin oxygen saturation were observed for the period of ventilation and weaning till discharge from the ICU. These records were subjected to paired t test for values measured at preinfusion period compared to 10 minutes and 6 hours measurement after infusion. RESULTS: The study confirmed the previous findings of previous reports regarding the cardiovascular stability and non depressive effect on respiration. It also confirmed the sparing effect on the use of analgesics which indicates its analgesic effect. The sedation quality is unique in that the patient is easily arousable. This was reported favorably by the nursing staff. Bradycardia was observed in one patient who was treated effectively by stopping the infusion. CONCLUSION: We concluded that dexmedetomidine is useful sedative agent with analgesic properties which reduce the analgesic requirement of the patient. The patient were ventilated, weaned, then breathed spontaneously in a satisfactory manner.     

Intensive care unit syndrome/delirium is associated with anemia,drug therapy and duration of ventilation treatment

BACKGROUND: We have performed a prospective qualitative investigation of the ICU syndrome/delirium; the main parts of which have recently been published. The aim of the present study was to explore the relationship between the ICU syndrome/delirium and age, gender, length of ventilator treatment, length of stay and severity of disease, as well as factors related to arterial oxygenation and the amount of drugs used for sedation/analgesia. METHODS: Nineteen mechanically ventilated patients who had stayed in the ICU for more than 36 h were closely observed during their stay, and interviewed in depth twice after discharge. Demographic, administrative and medical data were collected as a part of the observation study. RESULTS: Patients with severe delirium had significantly lower hemoglobin concentrations than those with moderate or no delirium (P=0.033). Patients suffering from severe delirium spent significantly longer time on the ventilator and at the ICU, and were treated with significantly higher daily doses of both fentanyl (P=0.011) and midazolam (P=0.011) in comparison with those reporting only moderate or no symptoms of delirium. There were no significant differences in the Therapeutic Intervention Scoring System scores, reflecting the degree of illness, between patients with and without delirium. CONCLUSION: The development of the ICU syndrome/delirium seems to be associated with decreased hemoglobin concentrations and extended times on the ventilator. Prolonged ICU stays and treatment with higher doses of sedatives and opioids in patients with delirium appear to be secondary phenomena rather than causes.     

Mortality amongst multiple trauma patients admitted to an intensive therapy unit

A retrospective review of 428 severely injured patients admitted to an intensive therapy unit between 1969 and 1982 was performed. The patients' primary injuries were assessed using the injury severity score (ISS), and subsequent complications using the complications impact index and sepsis score. Between 1969 and 1980 mortality fluctuated between 19% and 29% but rose to 47% (p less than 0.05) during 1981-82 in spite of an unchanged ISS. The increased mortality was confined to ventilated patients surviving more than 5 days from injury and was associated with multiple organ failure and severe infection. The rapid and sustained increase in mortality could not be explained by any obvious change in severity of injury or referral pattern. The only deliberate change in management related to the combination of analgesic/sedative drugs used in ventilated patients. During 1979 to 1982 mortality was 28% in patients given morphine with or without benzodiazepines and 77% in those given morphine and etomidate (p less than 0.0005). After discontinuation of the latter regimen (May 1983) and resumption of the former analgesic/sedative combination, mortality fell to 25% (p less than 0.005). Possible mechanisms leading to increased mortality include adrenocortical insufficiency or depth of anaesthesia.     

Postoperative management of carotid endarterectomy with dexmedetomidine--a comparison with propofol

BACKGROUND: We compared dexmedetomidine (DEX) with propofol (PRO) in patients requiring sedation after carotid endarterectomy (CEA) in the intensive care unit (ICU). Incidence of hyperperfusion syndrome, the sedative and analgesic properties, cardiovascular responses, and ventilation characteristics were discussed. METHODS: On arrival in the ICU, 66 patients were randomized to receive sedation with either DEX (0.2-0.7 microg x kg(-1) x hr(-1)) or PRO (1-3 mg x kg(-1) x hr(-1)) infusions. Additional analgesia was provided and patients were ventilated mechanically, if needed. RESULTS: No hyperperfusion syndrome occurred in either group. Eight patients in the DEX group required additional PRO infusions because of insufficiency for sedation. Patients receiving PRO infusions required significantly more analgesic agents and artificial ventilation than patients receiving DEX (P<0.05). Eleven patients in the PRO group required dopamine infusions because of hypotension. CONCLUSIONS: DEX is a safe and acceptable sedative agent for patients requiring sedation after CEA in the ICU; however, further studies are needed to assess the appropriate sedative doses of DEX.     

Continuous epidural infusion for postoperative mechanical ventilation

We evaluated in analgesic and sedative effects of continuous epidural infusion of two analgesic regimens in ventilated patients following esophagectomy. Forty-six patients, divided into two treatment groups, received postoperative continuous epidural infusion of morphine, or that of a combination of bupivacaine and morphine. Assessments were made with the following indices: pain relief score, somnolence score, patient ventilator coordination score, and the number of supplemental administrations of analgesics and sedatives. No significant differences occurred in somnolence scores or patient ventilator coordination scores between the two groups, which revealed satisfactory sedation for mechanical ventilation. Patients receiving the combination of bupivacaine and morphine had significantly less pain postoperatively, requiring a smaller number of supplemental administrations of analgesics and sedatives (P 0.05). It is concluded that: 1) continuous epidural infusion of analgesics gives potent analgesia and sedation of ventilated patients following esophagectomy; 2) the combination of bupivacaine and morphine gives pain relief superior to morphine alone.(Sakura S, Sumi M, Saito Y et al.: Continuous epidural infusion for postoperative mechanical ventilation. J Anesth 4: 219–225, 1990)     

右美托咪啶在重症患者谵妄的预防和治疗作用研究进展

背景 重症患者谵妄的发生率较高,并且谵妄的发生会增加重症患者并发症的发生率及病死率.右美托咪啶(dexmedetomidine,DEX)是一种较新型的镇静药,具有镇静、镇痛作用.临床试验证实其在重症医学科谵妄预防和治疗中具有独特优势.目的 综述DEX在重症医学科谵妄预防和治疗中的作用.内容 阐述谵妄的流行病学及危险因素...     

Postoperative delirium in total knee and hip arthroplasty patients: a study of perioperative modifiable risk factors

Background

Postoperative delirium continues to pose major clinical difficulties. While unmodifiable factors (e.g. age and comorbidity burden) are commonly studied risk factors for delirium, the role of modifiable factors, such as anaesthesia type and commonly used perioperative medications, remains understudied. This study aims to evaluate the role of modifiable factors for delirium after hip and knee arthroplasties.

Apolipoprotein E e4 allele does not increase the risk of early postoperative delirium after major surgery

Background

A relationship between patients with a genetic predisposition to and those who develop postoperative delirium has not been yet determined. The aim of this study was to determine whether there is an association between apolipoprotein E epsilon 4 allele (APOE4) and delirium after major surgery.

Methods

Of 230 intensive care patients admitted to the post anesthesia care unit (PACU) over a period of 3?months, 173 were enrolled in the study. Patients?? demographics and intra- and postoperative data were collected. Patients were followed for the development of delirium using the Intensive Care Delirium Screening Checklist, and DNA was obtained at PACU admission to determine apolipoprotein E genotype.

Results

Fifteen percent of patients developed delirium after surgery. Twenty-four patients had one copy of APOE4. The presence of APOE4 was not associated with an increased risk of early postoperative delirium (4% vs. 17%; P?=?0.088). The presence of APOE4 was not associated with differences in any studied variables. Multivariate analysis identified age [odds ratio (OR) 9.3, 95% confidence interval (CI) 2.0?C43.0, P?=?0.004 for age ??65?years), congestive heart disease (OR 6.2, 95% CI 2.0?C19.3, P?=?0.002), and emergency surgery (OR 59.7, 95% CI 6.7?C530.5, P?<?0.001) as independent predictors for development of delirium. The Simplified Acute Physiology Score II (SAPS II) and The Acute Physiology and Chronic Health Evaluation II (APACHE II) were significantly higher in patients with delirium (P?<?0.001 and 0.008, respectively). Hospital mortality rates of these patients was higher and they had a longer median PACU stay.

Conclusions

Apolipoprotein e4 carrier status was not associated with an increased risk for early postoperative delirium. Age, congestive heart failure, and emergency surgery were independent risk factors for the development of delirium after major surgery.     

老年患者脊柱手术术后谵妄危险因素分析的回顾性研究

目的:探讨老年患者脊柱手术术后谵妄的发生率及相关危险因素。方法:采用回顾性分析2016年1月至2018年11月收治的老年脊柱手术病例436例,根据术后是否发生谵妄分为谵妄组和非谵妄组。记录患者的性别、年龄、身体质量指数,糖尿病史,冠心病史,慢性阻塞性肺疾病史,术前白细胞计数,术前红细胞比容,术前血红蛋白水平,手术方式,手术时间,麻醉时间,美国麻醉医师协会(ASA)评分,心功能分级,术中失血量,术中输血量,术中芬太尼、异丙酚和地佐辛的用量,术后白细胞计数,术后红细胞比容,术后血红蛋白水平,术后电解质(钠离子、钾离子),采用单因素Logistic回归分析有统计学意义的危险因素后进行多元Logistic回归分析进一步探讨独立危险因素。结果:纳入436例中112例老年患者术后出现谵妄,发生率25.68%。谵妄组与非谵妄组在年龄、术前白细胞计数、术前红细胞比容、术后红细胞比容、术后血红蛋白水平、术后钠离子浓度、麻醉时间、ASA评分、心功能评分、术中失血量、术后地佐辛使用量、糖尿病史、冠心病史、慢性阻塞性肺疾病史方面差异有统计学意义(P0.05),通过多因素Logistic回归分析显示年龄、ASA评分、术后地佐辛量、慢性阻塞性肺疾病史是老年患者脊柱手术术后谵妄发生的独立危险因素。结论:患者高龄72岁、ASA评分2分、地佐辛镇痛药物的使用以及患者合并慢性阻塞性肺疾病史是术后谵妄发生的独立危险因素。     

Sevoflurane versus Halothane: Postoperative Maladaptive Behavioral Changes: A Randomized, Controlled Trial

Background: The authors conducted a double-blind, randomized, controlled trial to determine whether the use of sevoflurane in children undergoing anesthesia and surgery results in a higher incidence of postoperative maladaptive behavioral changes as compared with halothane.

Methods: Children and their parents (n = 102) were randomly assigned to either a halothane group (n = 50) or a sevoflurane group (n = 52). The intraoperative anesthetic protocol was strictly controlled, and the postoperative analgesic consumption and pain levels were recorded. The effect of the group assignment on emergence status and maladaptive postoperative behavioral changes was assessed both by validated psychological measures and physiologic instruments (actigraphy) on postoperative days 1-7. Anxiety of the parent and child was also assessed, as was the child's postoperative recovery (Recovery Inventory).

Results: There were no group differences in preoperative state anxiety, postoperative analgesic requirements, postoperative pain, or the incidence of emergence delirium (P = not significant). Two-way repeated-measures analysis of variance showed no group differences in the incidence of postoperative maladaptive behaviors (F4,72 = 0.60, P = 0.701) or actigraphic variables such as percent sleep, number of night awakenings, and night awakenings that lasted for more than 5 min (P = not significant).     

Nitrous oxide does not change the incidence of postoperative delirium or cognitive decline in elderly surgical patients

Background. Postoperative delirium and cognitive decline arecommon in elderly surgical patients after non-cardiac surgery.Despite this prevalence and clinical importance, no specificaetiological factor has been identified for postoperative deliriumand cognitive decline. In experimental setting in a rat model,nitrous oxide (N₂O) produces neurotoxic effect at high concentrationsand in an age-dependent manner. Whether this neurotoxic responsemay be observed clinically has not been previously determined.We hypothesized that in the elderly patients undergoing non-cardiacsurgery, exposure to N₂O resulted in an increased incidenceof postoperative delirium than would be expected for patientsnot receiving N₂O. Methods. Patients who were 65 yr of age, undergoing non-cardiacsurgery and requiring general anaesthesia were randomized toreceive an inhalational agent and either N₂O with oxygen oroxygen alone. A structured interview was conducted before operationand for the first two postoperative days to determine the presenceof delirium using the Confusion Assessment Method. Results. A total of 228 patients were studied with a mean (range)age of 73.9 (65–95) yr. After operation, 43.8% of patientsdeveloped delirium. By multivariate logistic regression, age[odds ratio (OR) 1.07; 95% confidence interval (CI) 1.02–1.26],dependence on performing one or more independent activitiesof daily living (OR 1.54; 95% CI 1.01–2.35), use of patient-controlledanalgesia for postoperative pain control (OR 3.75; 95% CI 1.27–11.01)and postoperative use of benzodiazepine (OR 2.29; 95% CI 1.21–4.36)were independently associated with an increased risk for postoperativedelirium. In contrast, the use of N₂O had no association withpostoperative delirium. Conclusions. Exposure to N₂O resulted in an equal incidenceof postoperative delirium when compared with no exposure toN₂O. ⁴Present address: Staff Statistician, University of Pittsburgh,PA 15213, USA     

Current United Kingdom sedation practice in pediatric intensive care

BACKGROUND: The aim of this study was to investigate the current practice of sedation, analgesia, and neuromuscular blockade in critically ill children on pediatric intensive care units (PICUs) in the UK and identify areas that merit further study. METHODS: Data were gathered in a prospective observational study of 338 critically ill children in 20 UK PICUs. RESULTS: There is considerable variation in clinical practice. A total of 24 different sedative and analgesic agents were used during the study. The most commonly used sedative and analgesic agents were midazolam and morphine. Four different neuromuscular blockers (NMBs) were used, most commonly vecuronium. There were differences in treatment between cardiac and noncardiac children, but there were a greater number of infants and neonates in the cardiac group. NMBs were used in 30% of mechanically ventilated patients. Withdrawal symptoms were reported in 13% of ventilated patients, relatively early in their stay; weaning sedative agents ('tapering') was apparently of no benefit. The use of clonidine in this setting was noted. Physical restraints were used in 7.4%. Propofol was used but in only 2.6% of patients, all over the age of 4 years, and not exceeding 2 mgxkg(-1)xh(-1). No side effects attributable to 'propofol syndrome' were noted. CONCLUSIONS: There is considerable heterogeneity of sedation techniques. NMBs are used in a large portion of this population. Withdrawal symptoms were associated with higher doses of sedation and greater lengths of stay and were not ameliorated by withdrawing sedation gradually ('tapering').     

Durchgangssyndrome nach gefäßchirurgischen Operationen Zwischenergebnisse einer prospektiven Untersuchung

Introduction: Postoperative delirium is a common psychic disturbance occurring acutely after various surgical procedures and typically presenting with a fluctuating course. These patients' recovery takes longer. In this study we analyze the incidence of postoperative delirium in patients undergoing vascular surgery and try to identify risk factors for its development. Methods: Patients undergoing elective arterial operations were included. Their medical history, the specific vascular diagnosis and operation performed, the medication and laboratory data were monitored. Additionally the patients were preoperatively interviewed by a psychiatrist. Intraoperatively the drugs, infusions, possible transfusions, blood gases and pressures were monitored, as were the times of surgery and anesthesia. Postoperatively patients were seen daily by the psychiatrist and the surgeon for at least 7 days. Postoperative delirium was diagnosed according to DSM IV criteria, and mild, moderate and severe delirium were distinguished. Results: Fifty-four patients entered the study. Twenty-one (38.9%) developed postoperative delirium (11 mild, 2 moderate, 8 severe). Patients with aortic operations developed delirium more frequently than those with non-aortic procedures(55.5 vs 22.2%, n=27 each). Some preexisting diseases (hearing disturbance) increased the probability of postoperative delirium, while age was not identified as a risk factor. General psychopathological and depressive disturbances increased the likelihood of postoperative delirium. Patients who had a severe intraoperative course developed postoperative delirium more frequently. This was not seen in the absolute time of surgery or anesthesia nor in the intraoperative development of blood pressure or intraarterial gases, which did not differ between patients with and without postoperative delirium. More reliable parameters were an increased intraoperative need for crystalloid volume, intra – or postoperatively decreased hemoglobin values (Hb <10 g/dl) and the development of acidosis that had to be treated. Patients with delirium had serious complications more often (8/21=38.1% vs 6/33=18.2%) and needed Intensive Care treatment longer (2.7 vs 2.1 days, only aortic surgery 3.2 vs 2.4 days). Conclusions: Postoperative delirium after vascular surgery is frequent. Patients undergoing aortic surgery, with specific concomittant medical disease, psychopathological disturbances and a severe intraoperative course, are at risk of developing postoperative delirium.