Postoperative delirium. Part 2: detection, prevention and treatment

Implication of age-related changes on anesthesia management

Elderly patients have a high risk of perioperative morbidity and mortality. Pluri-morbidities, polypharmacy, and functional dependence may have a great impact on intraoperative management and request specific cautions. In addition to surgical stress, several perioperative noxious stimuli such as fasting, blood loss, postoperative pain, nausea and vomiting, drug adverse reactions, and immobility may trigger a derangement leading to perioperative complications. Older patients have a high risk of major hemodynamic derangement due to aging of the cardiovascular system and associated comorbidities. The hemodynamic monitoring as well as fluid therapy should be the most accurate as possible. Aging is accompanied by decreased renal function, which is related to a reduction in renal blood flow, renal mass, and the number and size of functioning nephrons. Drugs eliminated predominantly by the renal route need dosage adjustments based on residual renal function. Liver mass, hepatic blood flow, and intrinsic metabolic activity are decreased in the elderly, and all drugs metabolized by the liver have a variable half-life, thus requiring dose reduction. Decreased neural plasticity contributes to a high risk for postoperative delirium. Monitoring of anesthesia depth should be mandatory to avoid overdosage of hypnotic drugs. Prevention of postoperative pulmonary complications requires both protective ventilation strategies and adequate recovery of neuromuscular function at the end of surgery. Avoidance of hypothermia cannot be missed. The aim of this review is to describe comprehensive strategies for intraoperative management plans tailored to meet the unique needs of elderly surgical patients, thus improving outcomes in this vulnerable population.

The effect of neostigmine on postoperative delirium after colon carcinoma surgery: a randomized, double-blind, controlled trial

Background

Postoperative delirium (POD) is a critical complication in patients accepting colon carcinoma surgery. Neostigmine, as a cholinesterase inhibitor, can enhance the transmission of cholinergic transmitters in synaptic space, and play an important role in maintaining the normal level of cognition, attention and consciousness. The objective of this study was to investigate the effect of neostigmine on POD and clinical prognosis.

Methods

A randomized, double-blind controlled trial was implemented in Qingdao Municipal Hospital Affiliated to Qingdao University. A total of 454 patients aged 40 to 90 years old accepted colon carcinoma surgery were enrolled between June 7, 2020, and June 7, 2021, with final follow-up on December 8, 2021. Patients were randomly assigned to two groups: the neostigmine group (group N) and the placebo group (group P), the patients in group N were injected with 0.04 mg/kg neostigmine and 0.02 mg/kg atropine intravenously. The primary endpoint was the incidence of POD, researchers evaluated the occurrence of POD by the Confusion Assessment Method (CAM) twice daily (at 10 a.m. and 2 p.m.) during the first 7 postoperative days, POD severity was assessed by the Memorial Delirium Assessment Scale (MDAS). The secondary endpoints were the extubating time, postanesthesia care unit (PACU) time, the incidence of various postoperative complications, length of hospital stays, and 6 months postoperative mortality.

Results

The incidence of POD was 20.20% (81/401), including 19.39% (38/196) in group N and 20.98% (43/205) in group P. There was no significant statistical significance in the incidence of POD between group N and group P (P > 0.05); Compared to group P, the extubating time and PACU time in group N were significantly reduced (P < 0.001), the incidence of postoperative pulmonary complications (POPCs) decreased significantly in group N (P < 0.05), while no significant differences were observed in postoperative hospital stay and mortality in 6 months between the two groups (P > 0.05).

Conclusion

For patients accepted colon carcinoma surgery, neostigmine did not significantly reduce the incidence of POD, postoperative mortality and postoperative hospital stay, while it indeed reduced the extubating time, PACU time and the incidence of POPCs.

Trial registration

The randomized, double-blind, controlled trial was registered retrospectively at www.chictr.org.cn on 07/06/2020 (ChiCTR2000033639).

Intraoperative low tidal volume ventilation and the risk of ICD-10 coded delirium and the use for antipsychotic medications

BACKGROUND

Low tidal volume (VT) ventilation and its associated increase in arterial carbon dioxide (PaCO2) may affect postoperative neurologic function. We aimed to test the hypothesis that intraoperative low VT ventilation affect the incidence of postoperative ICD-10 coded delirium and/or the need for antipsychotic medications.

METHODS

This is a post-hoc analysis of a large randomized controlled trial evaluating low vs. conventional VT ventilation during major non-cardiothoracic, non-intracranial surgery. The primary outcome was the incidence of ICD-10 delirium and/or the use of antipsychotic medications during hospital stay, and the absolute difference with its 95% confidence interval (CI) was calculated.

RESULTS

We studied 1206 patients (median age of 64 [55-72] years, 59.0% males, median ARISCAT of 26 [19-37], and 47.6% of ASA 3). ICD-10 coded delirium and /or antipsychotic medication use was diagnosed in 11.2% with similar incidence between low and conventional VT ventilation (11.1% vs. 11.3%; absolute difference, -0.24 [95%CI, -3.82 to 3.32]; p = 0.894). There was no interaction between allocation group and type of surgery.

CONCLUSION

In adult patients undergoing major surgery, low VT ventilation was not associated with increased risk of ICD-10 delirium and/or the use of antipsychotic medications during hospital stay.

TRIAL REGISTRATION

ANZCTR Identifier: ACTRN12614000790640 .

Related Factors and Treatment of Postoperative Delirium in Old Adult Patients: An Integrative Review

“Postoperative delirium” is defined as delirium occurring in the hospital up to one week after a procedure or before discharge (whichever occurs first) that meets the DSM-5 diagnostic criteria. Objectives: To describe the risk factors related to this pathology and identify effective non-pharmacological forms of treatment. An integrative review of the available literature was performed. The search results considered included all quantitative studies published between 2011 and 2019 in both English and Spanish. A total of 117 studies were selected. Advanced age was identified as the principal risk factor for postoperative delirium. Nursing interventions appear to be the key to preventing or reducing the seriousness of delirium after an anaesthetic episode. The aetiology of postoperative delirium remains unknown, and no treatment exists to eliminate this pathology. The role of nursing staff is fundamental in the prevention, diagnosis, and management of the pathology.

Development and validation of a risk score for predicting postoperative delirium after major abdominal surgery by incorporating preoperative risk factors and surgical Apgar score

STUDY OBJECTIVE

To develop and validate a simple delirium-predicting scoring system in patients undergoing major abdominal surgery by incorporating preoperative risk factors and intraoperative surgical Apgar score (SAS).

DESIGN

Observational retrospective cohort study.

SETTING

A tertiary general hospital in China.

PATIENTS

1055 patients who received major abdominal surgery from January 2015 to December 2019.

MEASUREMENTS

We collected data on preoperative and intraoperative variables, and postoperative delirium. A risk scoring system for postoperative delirium in patients after major open abdominal surgery was developed and validated based on traditional logistic regression model. The elastic net algorithm was further developed and evaluated.

MAIN RESULTS

The incidence of postoperative delirium was 17.8% (188/1055) in these patients. They were randomly divided into the development (n = 713) and validation (n = 342) cohorts. Both the logistic regression model and the elastic net regression model identified that advanced age, arrythmia, hypoalbuminemia, coagulation dysfunction, mental illness or cognitive impairments and low surgical Apgar score are related with increased risk of postoperative delirium. The elastic net algorithm has an area under the receiver operating characteristic curve (AUROC) of 0.842 and 0.822 in the development and validation cohorts, respectively. A prognostic score was calculated using the following formula: Prognostic score = Age classification (0 to 3 points) + arrythmia + 2 * hypoalbuminemia + 2 * coagulation dysfunction + 4 * mental illness or cognitive impairments + (10-surgical Apgar score). The 22-point risk scoring system had good discrimination and calibration with an AUROC of 0.823 and 0.834, and a non-significant Hosmer-Lemeshow test P = 0.317 and P = 0.853 in the development and validation cohorts, respectively. The bootstrapping internal verification method (R = 1000) yielded a C-index of 0.822 (95% CI: 0.759-0.857).

CONCLUSION

The prognostic scoring system, which used both preoperative risk factors and surgical Apgar score, serves as a good first step toward a clinically useful predictive model for postoperative delirium in patients undergoing major open abdominal surgery.

Preoperative Cognitive Impairment as a Perioperative Risk Factor in Patients Undergoing Total Knee Arthroplasty

Background:

The study assessed whether pre-existing cognitive impairment (CI) prior to elective total knee arthroplasty (TKA) is associated with worse postoperative outcomes such as delirium, in-hospital medical complications, 30-day mortality, hospital length of stay and non-home discharge.

Methods:

A retrospective database analysis from the NSQIP Geriatric Surgery Pilot Project was used. There was an initial cohort of 6350 patients undergoing elective TKA, 104 patients with CI were propensity score matched to 104 patients without CI.

Results:

Analysis demonstrated a significantly increased incidence of post-operative delirium (POD) in the cohort with pre-op CI (p = < .001), a worsened functional status (p = < .001) and increased nonhome discharge postoperatively compared to the group without CI (p = 0.029). Other post-operative outcomes included 30-day mortality of 0% in both groups, and low rate of complications such as infection (2.88% vs 0.96%), pneumonia (1.92% vs 0%), failure to wean (0.96% vs 0%), and reintubation (0.96% vs 0%). Some other differences between the CI group and non-CI group, although not statistically significant, included increased rate of transfusion (10.58% vs 6.73%), and sepsis (1.92% vs 0%). The length of stay was increased in the non-CI group (4.28% vs 2.32%, p = 0.122).

Conclusion:

CI in patients undergoing TKA is associated with an increased risk of POD, worsened postoperative functional status, and discharge to non-home facility.

Use of Dexmedetomidine in Cardiothoracic and Vascular Anesthesia

Dexmedetomidine is a highly selective α₂-adrenergic agonist with analgesic and sedative properties. In the United States, the Food and Drug Administration approved the use of the drug for short-lasting sedation (24 h) in intensive care units (ICUs) in patients undergoing mechanical ventilation and endotracheal intubation. In October 2008, the Food and Drug Administration extended use of the drug for the sedation of nonintubated patients before and during surgical and nonsurgical procedures. In the European Union, the European Medicine Agency approved the use of dexmedetomidine in September 2011 with a single recognized indication: ICU adult patients requiring mild sedation and awakening in response to verbal stimulus. At present, the use of dexmedetomidine for sedation outside the ICU remains an off-label indication. The benefits of dexmedetomidine in critically ill patients and in cardiac, electrophysiology-related, vascular, and thoracic procedures are discussed.

Previously Identified Common Post-Injury Adverse Events in Traumatic Spinal Cord Injury-Validation of Existing Literature and Relation to Selected Potentially Modifiable Comorbidities: A Prospective Canadian Cohort Study

Adverse events (AEs) are common during care in patients with traumatic spinal cord injury (tSCI). Increased risk of AEs is linked to patient factors including pre-existing comorbidities. Our aim was to examine the relationships between patient factors and common post-injury AEs, and identify potentially modifiable comorbidities. Adults with tSCI admitted to a Level I acute specialized spine center between 2006 and 2014 who were enrolled in the Rick Hansen SCI Registry (RHSCIR) and had AE data collected using the Spine Adverse Events Severity system were included. Patient demographic, neurological injury, and comorbidities data were obtained from RHSCIR. Potentially modifiable comorbidities were grouped into health-related conditions, substance use/withdrawal, and psychiatric conditions. Negative binomial regression and multiple logistic regression were used to model the impact of patient factors on the number of AEs experienced and the occurrence of the five previously identified common AEs, respectively. Of the 444 patients included in the study, 24.8% reported a health-related condition, 15.3% had a substance use/withdrawal condition, 8% reported having a psychiatric condition; and 79.3% experienced one or more AEs. Older age (p = 0.004) and more severe injuries (p < 0.001) were nonmodifiable independent variables significantly associated with increased AEs. The AEs experienced by patients were urinary tract infections (42.8%), pneumonia (39.2%), neuropathic pain (31.5%), delirium (18.2%), and pressure ulcers (11.0%). Risk of delirium increased in those with substance use/withdrawal; and pneumonia risk increased with psychiatric comorbidities. Opportunity exists to develop clinical algorithms that include these types of risk factors to reduce the incidence and impact of AEs.

Life after a lung transplant: a balance of joy and challenges

AIM AND OBJECTIVE

To describe patients' experiences throughout the first four months post-lung transplant.

BACKGROUND

Health professionals are familiar with the fact that patients' average survival after a lung transplant is about seven years and that 74% of these patients reject new organs within the first two years. By contrast, knowledge of these patients' perspectives after lung transplantation is scant.

DESIGN/METHOD

A qualitative study was conducted between May 2013-May 2014 in which 26 interviewees participated - four months post-transplant - based on a semistructured interview guide. The data were inductively analysed using a content thematic approach within a phenomenological and hermeneutic frame.

RESULTS

The main findings in the study reveal that (1) having a lung transplant is an overwhelming experience, which for some patients includes (2) troubling physical and psychological challenges. The interviewees were happy to get another chance to live, although some of them suffered from medical side effects, postoperative complications and psychological problems. When asked about the future, interviewees stated that life could be described as (3) a balance of joy and challenges. They had received a new chance in life and were eager to fulfil their life hopes and dreams. At the same time, they were worried about the future. Having a lung transplant implies rules that have to be followed. What are the healthy choices they are supposed to make? And will there be a tomorrow?

CONCLUSIONS

Having a lung transplant is described as an overwhelming experience because of the improvement in the physical function of the body. Patients were grateful to family, friends and healthcare professionals for supporting them. The first four months post-transplantation were described as both physically and psychologically challenging. Interviewees were aware of the prognosis for patients following lung transplantation. They expressed feelings of worry and insecurity but still had hopes and dreams.

RELEVANCE TO CLINICAL PRACTICE

The patients are troubled by both physical and psychological challenges after lung transplantation. Several areas call for interventions from healthcare professionals during the early post-transplant period.

Cyproheptadine for the Prevention of Postoperative Delirium: A Pilot Study

BACKGROUND

Postoperative delirium is a common neurobehavioral complication after major surgeries. There is no conclusive approach for prevention of delirium in these patients.

OBJECTIVE

In this study, efficacy of cyproheptadine for prevention of postoperative delirium was evaluated.

METHODS

Delirium status of surgical patients was evaluated postoperatively at the time of admission to the intensive care unit (ICU) using the Confusion Assessment Method (CAM-ICU) scale. Patients without delirium were assigned to the cyproheptadine or placebo group based on the simple randomization method. Patients received cyproheptadine or placebo tablet at a dose of 4 mg 3 times per day for 7 days. Patients were monitored daily for incidence of delirium.

RESULTS

Changes in the incidence rates of delirium over time during the study phase (P = 0.04) and between the groups showed statistically significant differences (P = 0.029). However, severity of delirium was not significantly different between the cyproheptadine and placebo groups during the study period.

CONCLUSION

It seems that cyproheptadine with its diverse effects can be a potential option for prevention of postoperative delirium. In this pilot study, cyproheptadine significantly decreased the incidence but not severity of postoperative delirium.

Room transfers and the risk of delirium incidence amongst hospitalized elderly medical patients: a case-control study

Background

Room transfers are suspected to promote the development of delirium in hospitalized elderly patients, but no studies have systematically examined the relationship between room transfers and delirium incidence. We used a case–control study to determine if the number of room transfers per patient days is associated with an increased incidence of delirium amongst hospitalized elderly medical patients, controlling for baseline risk factors.

Methods

We included patients 70 years of age or older who were admitted to the internal medicine or geriatric medicine services at St. Michael’s Hospital between October 2009 and September 2010 for more than 24 h. The cases consisted of patients who developed delirium during the first week of hospital stay. The controls consisted of patients who did not develop delirium during the first week of hospital stay. Patients with evidence of delirium at admission were excluded from the analysis. A multivariable logistic regression model was used to determine the relationship between room transfers and delirium development within the first week of hospital stay.

Results

994 patients were included in the study, of which 126 developed delirium during the first week of hospital stay. Using a multivariable logistic regression model which controlled for age, gender, cognitive impairment, vision impairment, dehydration, and severe illness, room transfers per patient days were associated with delirium incidence (OR: 9.69, 95 % CI (6.20 to15.16), P < 0.0001).

Conclusions

An increased number of room transfers per patient days is associated with an increased incidence of delirium amongst hospitalized elderly medical patients. This is an exploratory analysis and needs confirmation with larger studies.

Low hemoglobin level is associated with the development of delirium after hepatectomy for hepatocellular carcinoma patients

Background

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide and liver resection is the only potential curative treatment option for those patients. Postoperative complications specific to elderly surgical patients such as delirium will be increasingly relevant in the coming decades. Herein, we aimed to investigate the risk factors for postoperative delirium in patients who have received hepatectomy for HCC.

Methods

This is a single medical center observational study and the study subjects comprised 401 individuals who underwent liver resection for hepatocellular carcinoma during January 2009 to October 2013. Multivariate analysis was used to examine whether preoperative, intra-operative, or postoperative variables were associated with the development of delirium.

Results

Of the 401 patients who underwent hepatectomy, 34 developed postoperative delirium (8.4%). In the majority of those patients, symptoms and signs of the syndrome occurred on postoperative day 2 and the mean duration of symptoms was 3.61 ± 3.71 days. Multivariate analysis revealed that advanced age (>71 years) [odds ratio (OR) = 1.133, 95% confidence interval (CI): 1.071–1.200, p<0.001], prolonged operative time (>190 minutes) (OR = 1.009, 95% CI: 1.000–1.017, p = 0.038), a decreased postoperative hemoglobin level (< 10.16 g/dL) (OR = 0.777, 95% CI: 0.613–0.983, p = 0.036), and history of hypnotic drug use (OR = 3.074, 95% CI: 1.045–9.039, p = 0.041) were independent risk factors for the development of postoperative delirium after hepatectomy.

Conclusions

Although the mechanism of postoperative delirium is not well understood, numbers of studies have shown that patients with postoperative delirium tend to have prolonged hospital stay, worse postoperative outcome and an increased risk of short- and long-term mortality. In this study, we found that advanced age, prolonged operative time, postoperative low hemoglobin level and history of hypnotic drug use are independent risk factors for postoperative delirium.

Impact of intraoperative hypotension and blood pressure fluctuations on early postoperative delirium after non-cardiac surgery

INTRODUCTION

Postoperative delirium is common in older patients. Despite its prognostic significance, the pathophysiology is incompletely understood. Although many risk factors have been identified, no reversible factors, particularly ones potentially modifiable by anaesthetic management, have been identified. The goal of this prospective cohort study was to investigate whether intraoperative hypotension was associated with postoperative delirium in older patients undergoing major non-cardiac surgery.

METHODS

Study subjects were patients >65 years of age, undergoing major non-cardiac surgery, who were enrolled in an ongoing prospective observational study of the pathophysiology of postoperative delirium. Intraoperative blood pressure was measured and predefined criteria were used to define hypotension. Delirium was measured by the Confusion Assessment Method on the first two postoperative days. Data were analysed using t-tests, two-sample proportion tests and ordered logistic regression multivariable models, including correction for multiple comparisons.

RESULTS

Data from 594 patients with a mean age of 73.6 years (sd 6.2) were studied. Of these 178 (30%) developed delirium on day 1 and 176 (30%) on day 2. Patients developing delirium were older, more often female, had lower preoperative cognitive scores, and underwent longer operations. Relative hypotension (decreases by 20, 30, or 40%) or absolute hypotension [mean arterial pressure (MAP)<50 mm Hg] were not significantly associated with postoperative delirium, nor was the duration of hypotension (MAP<50 mm Hg). Conversely, intraoperative blood pressure variance was significantly associated with postoperative delirium.

DISCUSSION

These results showed that increased blood pressure fluctuation, not absolute or relative hypotension, was predictive of postoperative delirium.

Should general anaesthesia be avoided in the elderly?

Surgery and anaesthesia exert comparatively greater adverse effects on the elderly than on the younger brain, manifest by the higher prevalence of postoperative delirium and cognitive dysfunction. Postoperative delirium and cognitive dysfunction delay rehabilitation, and are associated with increases in morbidity and mortality among elderly surgical patients. We review the aetiology of postoperative delirium and cognitive dysfunction in the elderly with a particular focus on anaesthesia and sedation, discuss methods of diagnosing and monitoring postoperative cognitive decline, and describe the treatment strategies by which such decline may be prevented.

Perioperative psycho-educational intervention can reduce postoperative delirium in patients after cardiac surgery: a pilot study

OBJECTIVE

Postoperative delirium after cardiac surgery is associated with many consequences such as poorer functional recovery, more frequent postoperative complications, higher mortality, increased length of hospital stay, and higher hospital costs. The aim of this study was to evaluate the efficacy of perioperative psycho-educational intervention in preventing postoperative delirium in post cardiac surgery patients.

METHOD

We conducted a comparative retrospective study between 49 patients who had received perioperative psycho-educational intervention and 46 patients who had received standard care. The primary outcome was the incidence of postoperative delirium. Secondary outcomes included length of ICU stay, and severity and duration of postoperative delirium among the patients who had developed delirium.

RESULTS

The incidence of postoperative delirium was significantly lower in the intervention group than that in the control group (12.24% vs. 34.78%, P = 0.009). Among the patients who had developed postoperative delirium, there was no statistical difference between the two groups regarding secondary outcomes.

CONCLUSIONS

Our results show that the patients who received perioperative psycho-educational intervention were associated with a lower incidence of postoperative delirium after cardiac surgery than those who received standard care. Clinicians would be able to implement this psycho-educational intervention as part of routine practice to reduce delirium.

Strategies for prevention of postoperative delirium: a systematic review and meta-analysis of randomized trials

INTRODUCTION

The ideal measures to prevent postoperative delirium remain unestablished. We conducted this systematic review and meta-analysis to clarify the significance of potential interventions.

METHODS

The PRISMA statement guidelines were followed. Two researchers searched MEDLINE, EMBASE, CINAHL and the Cochrane Library for articles published in English before August 2012. Additional sources included reference lists from reviews and related articles from 'Google Scholar'. Randomized clinical trials (RCTs) on interventions seeking to prevent postoperative delirium in adult patients were included. Data extraction and methodological quality assessment were performed using predefined data fields and scoring system. Meta-analysis was accomplished for studies that used similar strategies. The primary outcome measure was the incidence of postoperative delirium. We further tested whether interventions effective in preventing postoperative delirium shortened the length of hospital stay.

RESULTS

We identified 38 RCTs with interventions ranging from perioperative managements to pharmacological, psychological or multicomponent interventions. Meta-analysis showed dexmedetomidine sedation was associated with less delirium compared to sedation produced by other drugs (two RCTs with 415 patients, pooled risk ratio (RR)=0.39; 95% confidence interval (CI)=0.16 to 0.95). Both typical (three RCTs with 965 patients, RR=0.71; 95% CI=0.54 to 0.93) and atypical antipsychotics (three RCTs with 627 patients, RR=0.36; 95% CI=0.26 to 0.50) decreased delirium occurrence when compared to placebos. Multicomponent interventions (two RCTs with 325 patients, RR=0.71; 95% CI=0.58 to 0.86) were effective in preventing delirium. No difference in the incidences of delirium was found between: neuraxial and general anesthesia (four RCTs with 511 patients, RR=0.99; 95% CI=0.65 to 1.50); epidural and intravenous analgesia (three RCTs with 167 patients, RR=0.93; 95% CI=0.61 to 1.43) or acetylcholinesterase inhibitors and placebo (four RCTs with 242 patients, RR=0.95; 95% CI=0.63 to 1.44). Effective prevention of postoperative delirium did not shorten the length of hospital stay (10 RCTs with 1,636 patients, pooled SMD (standard mean difference)=-0.06; 95% CI=-0.16 to 0.04).

CONCLUSIONS

The included studies showed great inconsistencies in definition, incidence, severity and duration of postoperative delirium. Meta-analysis supported dexmedetomidine sedation, multicomponent interventions and antipsychotics were useful in preventing postoperative delirium.

Clinical, methodological and theoretical issues in the assessment of cognition after anaesthesia and surgery: a review

As people live longer, the burden of cognitive impairment to elderly patients, their families and society becomes increasingly common and important. The loss of independence, a reduction in the quality of life and increased mortality are possible correlates to the mental disintegration. Cognitive dysfunction following major surgery on the elderly is a significant problem which adds to other cognitive impairments caused by neurodegeneration, cerebrovascular impairments and other causes. There are challenges in reviewing the literature because of many methodological concerns. There is no standard definition; the diagnosis is made only by the results of neuropsychological tests which are not standardised for this purpose; test results are analysed by different statistical methods (some of them inappropriate); controls are often absent or poorly matched; and pre-existing mild cognitive impairment, which affects 10 to 20% of people older than 65 years and is similar to the subtle cognitive impairment following surgery, is not sought for and recognised. Reviews of the subject have varied from descriptions such as 'a well recognised and significant problem' to 'a hypothetical phenomenon for which there is no International Statistical Classification of Disease (ICD-9) code, and no Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) code'. This article examines both sides of the spectrum in a detailed review which explains the necessary psychological 'jargon', discusses the methods used and points to areas of future research.

Treatment of four psychiatric emergencies in the intensive care unit

OBJECTIVES

To review the diagnosis and management of four selected psychiatric emergencies in the intensive care unit: agitated delirium, neuroleptic malignant syndrome, serotonin syndrome, and psychiatric medication overdose.

DATA SOURCES

Review of relevant medical literature.

DATA SYNTHESIS

Standardized screening for delirium should be routine. Agitated delirium should be managed with an antipsychotic and, possibly, dexmedetomidine in treatment-refractory cases. Delirium management should also include ensuring a calming environment and adequate pain control, minimizing benzodiazepines and anticholinergics, normalizing the sleep-wake cycle, providing sensory aids as required, and providing early physical and occupational therapy. Neuroleptic malignant syndrome should be treated by discontinuing dopamine blockers, providing supportive therapy, and possibly administering medications (benzodiazepines, dopamine agonists, and/or dantrolene) or electroconvulsive therapy, if indicated. Serotonin syndrome should be treated by discontinuing all serotonergic agents, providing supportive therapy, controlling agitation with benzodiazepines, and possibly administering serotonin2A antagonists. It is often unnecessary to restart psychiatric medications upon which a patient has overdosed in the intensive care unit, though withdrawal syndromes should be prevented, and communication with outpatient prescribers is vital.

CONCLUSIONS

Understanding the diagnosis and appropriate management of these four psychiatric emergencies is important to provide safe and effective care in the intensive care unit.

[Do anesthetic techniques influence postoperative outcomes? Part II]

The knowledge of the influence of anesthetic techniques in postoperative outcomes has opened a large field of research in recent years. In this second part, we review some of the major controversies arising from the literature on the impact of anesthetic techniques on postoperative outcomes in 6 areas: postoperative cognitive dysfunction, chronic postoperative pain, cancer recurrence, postoperative nausea/vomiting, surgical outcomes, and resources utilization. The development of protective and preventive anesthetic strategies against short and long-term postoperative complications will probably occupy an important role in our daily anesthetic practice. Dynamic postoperative pain control has been confirmed as one of the basic requirements of accelerated postoperative recovery programs ("fast-track surgery"), and it is also a preventive factor for development of chronic postoperative pain. The weight of anesthetic technique on postoperative immunosuppression is to be defined. The potential influence of anesthesia on cancer recurrence, is a highly controversial area of research. The classic pattern of perioperative fluid therapy may increase postoperative complications. On the other hand, the maintenance of normoglycemia and normothermia was associated with a decreased postoperative morbidity. The high volume of surgical procedures means that the adequacy of human, organizational and technological resources have a major impact on overall costs.

The relation between atherosclerosis and the occurrence of postoperative delirium in vascular surgery patients

Old and frail patients undergoing vascular surgery seem at great risk of developing postoperative delirium (POD). The aim of this review was to identify risk factors for the development of POD in vascular surgery patients. Different aetiological factors have been identified, such as increased age, excessive blood transfusion, preoperative cognitive impairment and depression. Mounting evidence supports a role for inflammation and tobacco exposure in the development of POD. Vascular surgery patients differ from the general surgical population because they suffer from both loco-regional and systemic atherosclerosis. Although current scientific evidence cannot fully link both entities, evidence is growing that suggests a relationship between systemic and cerebrovascular atherosclerosis and the development of POD.