A critical review of daily sedation interruption in the intensive care unit

Background. Daily sedation interruption (DSI) has been proposed as a method of improving sedation management of critically ill patients by reducing the adverse effects of continuous sedation infusions.

Aim. To critique the research regarding daily sedation interruption, to inform education, research and practice in this area of intensive care practice.

Design. Literature review.

Method. Medline, CINAHL and Web of Science were searched for relevant key terms. Eight research-based studies, published in the English language between 1995–December 2006 and three conference abstracts were retrieved.

Results. Of the eight articles and three conference abstracts reviewed, five originated from one intensive care unit (ICU) in the USA. The research indicates that DSI reduces ventilation time, length of stay in ICU, complications of critical illness, incidence of post-traumatic stress disorder and is reportedly used by 15–62% of ICU clinicians in Australia, Europe, USA and Canada.

Conclusions. DSI improves patients' physiological and psychological outcomes when compared with routine sedation management. However, research relating to these findings has methodological limitations, such as the use of homogenous samples, single-centre trials and retrospective design, thus limiting their generalisability.

Relevance to clinical practice. DSI may provide clinicians with a simple, cost-effective method of reducing some adverse effects of sedation on ICU patients. However, the evidence supporting DSI is limited and cannot be generalised to heterogeneous ICU populations internationally. More robust research is required to assess the potential impact of DSI on the physical and mental health of ICU survivors.

Part 2. Chemical and physical restraints in the management of mechanically ventilated patients in the ICU: A patient perspective

An important goal of the care for the mechanically ventilated patient is to minimize patient discomfort and anxiety. This is partly achieved by frequent use of chemical and physical restraints. The majority of patients in intensive care will receive some form of sedation. The goal and use of sedation has changed considerably over the past few decades with literature evidencing trends toward overall lighter sedation levels and daily interruption of sedation. Conversely, the use of physical restraint for the ventilated patient in ICU differs considerably between nations and continents. A large portion of the literature on the use of physical restraint is from general hospital wards and residential homes, and not from the ICU environment. Recent literature suggests minimal use of physical restraint in the ICU, and that reduction programmes have been initiated. However, very few papers illuminate the patient's experience of physical and chemical restraints as a treatment strategy. In Part 1 of this two-part review, the evidence on chemical and physical restraints was explored with specific focus on definitions of terms, unplanned extubation, agitation, delirium as well as the impact of nurse–patient ratios in the ICU on these issues. This paper, Part 2, examines the evidence related to chemical and physical restraints from the mechanically ventilated patient's perspective.

Sedation breaks : are they good for the critically ill patient? A review.

Background:  Tradition has led us to believe that a heavily sedated patient is a comfortable, settled, compliant patient for whom sedation will improve outcome. The current move witnessed in clinical practice today of limiting sedation has led health care in recent years to question the benefit and necessity of routine, continuous sedation for all patients requiring mechanical ventilation. However, as a result there has been a rise in the amount of agitation being reported as being experienced by patients with the daily withdrawal of sedation. Aims:  The purpose of this paper is to review current arguments for and against perserving with agitation versus re-sedating, when it presents during the daily sedation breaks. Findings:  Of the literature reviewed, the question to re-sedate the mechanically ventilated agitated patient during sedation breaks remains an issue of contention. Although there is evidence focusing on the psychological effects of long-term sedation and sedation breaks specifically, the complex nature of critical illness in some cases means that individualized care is of paramount importance and in-depth assessment is crucial when deciding to re-sedate in the face of undetermined agitation. Agitation has been closely linked with several incidents that can be detrimental to patient safety, such as removal of lines and unplanned self-extubation. Conclusion:  The recommendations of this review are that nurses should re-commence sedation if the patient becomes agitated following a sedation break. Aims:  The purpose of this paper is to review current arguments for and against perserving with agitation versus re-sedating, when it presents during the daily sedation breaks. Findings:  Of the literature reviewed, the question to re-sedate the mechanically ventilated agitated patient during sedation breaks remains an issue of contention. Although there is evidence focusing on the psychological effects of long-term sedation and sedation breaks specifically, the complex nature of critical illness in some cases means that individualized care is of paramount importance and in-depth assessment is crucial when deciding to re-sedate in the face of undetermined agitation. Agitation has been closely linked with several incidents that can be detrimental to patient safety, such as removal of lines and unplanned self-extubation. Conclusion:  The recommendations of this review are that nurses should re-commence sedation if the patient becomes agitated following a sedation break.

Does an evidence-based sedation protocol improve practice and patient outcomes in critical care?

Learning Objective 1: compare protocol-directed sedation management with traditional non-protocol-directed practice in mechanically ventilated patients in an Australian critical care.

Learning Objective 2: explain the contrasting international research findings on sedation protocol implementation.
Minimization of sedation in critical care patients has recently received widespread support. Professional organizations internationally have published sedation management guidelines for critically ill patients to improve the use of research in practice, decrease practice variability and shorten mechanical ventilation duration. Innovations in practice have included the introduction of decision making protocols, daily sedation interruptions and new drugs and monitoring technologies. The aim of this study was to compare protocol-directed sedation management with traditional non-protocol-directed practice in mechanically ventilated patients in an Australian critical care setting.

A randomized, controlled trial design was used to study 312 mechanically ventilated adult patients in a general critical care unit at an Australian metropolitan teaching hospital. Patients were randomly assigned to receive protocol directed sedation management developed from evidence based guidelines (n=153) or usual clinical practice (n=159).

The median (95% CI) duration of ventilation was 58 hrs (44–78 hrs) for patients in the non-protocol group and 79 hrs (56–93) for those patients in the protocol group (p=0.20). Results were not significant for length of stay in critical care or hospital, the frequency of tracheostomies, and unplanned extubations. A Cox proportional hazards model estimated that protocol directed sedation management was associated with a 22% decrease (95% CI: 40% decrease to 2% increase, p=0.07) in the occurrence of successful weaning from mechanical ventilation.

Few randomized controlled trials have evaluated the effectiveness of protocol-directed sedation outside of North America. This study highlights the lack of transferability between different settings and different models of care. Qualified, high intensity nursing in the Australian critical care setting facilitates rapid, responsive decisions for sedation management and an increased success rate for weaning from mechanical ventilation.

Dexmedetomidine versus propofol/midazolam for long-term sedation during mechanical ventilation

PURPOSE: To compare dexmedetomidine (DEX) with standard care (SC, either propofol or midazolam) for long-term sedation in terms of maintaining target sedation and length of intensive care unit (ICU) stay. METHODS: A pilot, phase III, double-blind multicenter study in randomized medical and surgical patients (n = 85) within the first 72 h of ICU stay with an expected ICU stay of >or=48 h and sedation need for >or=24 h after randomization. Patients were assigned to either DEX (daily sedation stops. RESULTS: Non-inferiority of DEX versus SC was not confirmed. Target Richmond agitation-sedation score (RASS) was reached a median of 64% (DEX) and 63% (SC) of the sedation time (ns). The length of ICU stay was similar in DEX and SC. Patients with RASS target 0-3 (DEX 78%, SC 80%) were at target sedation 74% (DEX) and 64% (SC) of the time (ns), whereas those with RASS target -4 or less reached the target 42% (DEX) and 62% (SC) of the time (P = .006). Post hoc analyses suggested shorter duration of mechanical ventilation for DEX (P = 0.025). CONCLUSIONS: This pilot study suggests that in long-term sedation, DEX is comparable to SC in maintaining sedation targets of RASS 0 to -3 but not suitable for deep sedation (RASS -4 or less). DEX had no effect on length of ICU stay. Its effects on other relevant clinical outcomes, such as duration of mechanical ventilation, should be tested further.

Effect of sedation level on the prevalence of delirium when assessed with CAM-ICU and ICDSC

Purpose We hypothesized that reduced arousability (Richmond Agitation Sedation Scale, RASS, scores −2 to −3) for any reason during delirium assessment increases the apparent prevalence of delirium in intensive care patients. To test this hypothesis, we assessed delirium using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and Intensive Care Delirium Screening Checklist (ICDSC) in intensive care patients during sedation stops, and related the findings to the level of sedation, as assessed with RASS score. Methods We assessed delirium in 80 patients with ICU stay longer than 48 h using CAM-ICU and ICDSC during daily sedation stops. Sedation was assessed using RASS. The effect of including patients with a RASS of −2 and −3 during sedation stop (“light to moderate sedation”, eye contact less than 10 s or not at all, respectively) on prevalence of delirium was analyzed. Results A total of 467 patient days were assessed. The proportion of CAM-ICU-positive evaluations decreased from 53 to 31 % (p < 0.001) if assessments from patients at RASS −2/−3 (22 % of all assessments) were excluded. Similarly, the number of positive ICDSC results decreased from 51 to 29 % (p < 0.001). Conclusions Sedation per se can result in positive items of both CAM-ICU and ICDSC, and therefore in a diagnosis of delirium. Consequently, apparent prevalence of delirium is dependent on how a depressed level of consciousness after sedation stop is interpreted (delirium vs persisting sedation). We suggest that any reports on delirium using these assessment tools should be stratified for a sedation score during the assessment.

Safety and risk factors for difficult endoscopist-directed ERCP sedation in daily practice: a hospital-based case-control study

Background: There are limited data concerning endoscopist-directed endoscopic retrograde cholangiopancreatography deep sedation. The aim of this study was to establish the safety and risk factors for difficult sedation in daily practice. Patients and methods: Hospital-based, frequency matched case-control study. All patients were identified from a database of 1,008 patients between 2014 and 2015. The cases were those with difficult sedations. This concept was defined based on the combination of the receipt of high-doses of midazolam or propofol, poor tolerance, use of reversal agents or sedation-related adverse events. The presence of different factors was evaluated to determine whether they predicted difficult sedation. Results: One-hundred and eighty-nine patients (63 cases, 126 controls) were included. Cases were classified in terms of high-dose requirements (n = 35, 55.56%), sedation-related adverse events (n = 14, 22.22%), the use of reversal agents (n = 13, 20.63%) and agitation/discomfort (n = 8, 12.7%). Concerning adverse events, the total rate was 1.39%, including clinically relevant hypoxemia (n = 11), severe hypotension (n = 2) and paradoxical reactions to midazolam (n = 1). The rate of hypoxemia was higher in patients under propofol combined with midazolam than in patients with propofol alone (2.56% vs. 0.8%, p < 0.001). Alcohol consumption (OR: 2.674 [CI 95%: 1.098-6.515], p = 0.030), opioid consumption (OR: 2.713 [CI 95%: 1.096-6.716], p = 0.031) and the consumption of other psychoactive drugs (OR: 2.015 [CI 95%: 1.017-3.991], p = 0.045) were confirmed to be independent risk factors for difficult sedation. Conclusions: Endoscopist-directed deep sedation during endoscopic retrograde cholangiopancreatography is safe. The presence of certain factors should be assessed before the procedure to identify patients who are high-risk for difficult sedation.

Increased sedation requirements in patients receiving extracorporeal membrane oxygenation for respiratory and cardiorespiratory failure

Critically ill patients receiving extracorporeal membrane oxygenation (ECMO) are often noted to have increased sedation requirements. However, data related to sedation in this complex group of patients is limited. The aim of our study was to characterise the sedation requirements in adult patients receiving ECMO for cardiorespiratory failure. A retrospective chart review was performed to collect sedation data for 30 consecutive patients who received venovenous or venoarterial ECMO between April 2009 and March 2011. To test for a difference in doses over time we used a regression model. The dose of midazolam received on ECMO support increased by an average of 18 mg per day (95% confidence interval 8, 29 mg, P=0.001), while the dose of morphine increased by 29 mg per day (95% confidence interval 4, 53 mg, P=0.021) The venovenous group received a daily midazolam dose that was 157 mg higher than the venoarterial group (95% confidence interval 53, 261 mg, P=0.005). We did not observe any significant increase in fentanyl doses over time (95% confidence interval 1269, 4337 µg, P=0.94). There is a significant increase in dose requirement for morphine and midazolam during ECMO. Patients on venovenous ECMO received higher sedative doses as compared to patients on venoarterial ECMO. Future research should focus on mechanisms behind these changes and also identify drugs that are most suitable for sedation during ECMO.

Development of process control methodology for tracking the quality and safety of pain, agitation and sedation management in critical care units

Objective: To develop sedation, pain, and agitation quality measures using process control methodology and evaluate their properties in clinical practice. Design: A Sedation Quality Assessment Tool was developed and validated to capture data for 12-hour periods of nursing care. Domains included pain/discomfort and sedation-agitation behaviors; sedative, analgesic, and neuromuscular blocking drug administration; ventilation status; and conditions potentially justifying deep sedation. Predefined sedation-related adverse events were recorded daily. Using an iterative process, algorithms were developed to describe the proportion of care periods with poor limb relaxation, poor ventilator synchronization, unnecessary deep sedation, agitation, and an overall optimum sedation metric. Proportion charts described processes over time (2 monthly intervals) for each ICU. The numbers of patients treated between sedation-related adverse events were described with G charts. Automated algorithms generated charts for 12 months of sequential data. Mean values for each process were calculated, and variation within and between ICUs explored qualitatively. Setting: Eight Scottish ICUs over a 12-month period. Patients: Mechanically ventilated patients. Interventions: None. Measurements and Main Results: The Sedation Quality Assessment Tool agitation-sedation domains correlated with the Richmond Sedation Agitation Scale score (Spearman [rho] = 0.75) and were reliable in clinician-clinician (weighted kappa; [kappa] = 0.66) and clinician-researcher ([kappa] = 0.82) comparisons. The limb movement domain had fair correlation with Behavioral Pain Scale ([rho] = 0.24) and was reliable in clinician-clinician ([kappa] = 0.58) and clinician-researcher ([kappa] = 0.45) comparisons. Ventilator synchronization correlated with Behavioral Pain Scale ([rho] = 0.54), and reliability in clinician-clinician ([kappa] = 0.29) and clinician-researcher ([kappa] = 0.42) comparisons was fair-moderate. Eight hundred twenty-five patients were enrolled (range, 59-235 across ICUs), providing 12,385 care periods for evaluation (range 655-3,481 across ICUs). The mean proportion of care periods with each quality metric varied between ICUs: excessive sedation 12-38%; agitation 4-17%; poor relaxation 13-21%; poor ventilator synchronization 8-17%; and overall optimum sedation 45-70%. Mean adverse event intervals ranged from 1.5 to 10.3 patients treated. The quality measures appeared relatively stable during the observation period. Conclusions: Process control methodology can be used to simultaneously monitor multiple aspects of pain-sedation-agitation management within ICUs. Variation within and between ICUs could be used as triggers to explore practice variation, improve quality, and monitor this over time

The adaptive compensations in endocrine pancreas from glucocorticoid-treated rats are reversible after the interruption of treatment

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Low mechanical ventilation times and reintubation rates associated with a specific weaning protocol in an intensive care unit setting: a retrospective study

OBJECTIVES: A number of complications exist with invasive mechanical ventilation and with the use of and withdrawal from prolonged ventilator support. The use of protocols that enable the systematic identification of patients eligible for an interruption in mechanical ventilation can significantly reduce the number of complications. This study describes the application of a weaning protocol and its results. METHODS: Patients who required invasive mechanical ventilation for more than 24 hours were included and assessed daily to identify individuals who were ready to begin the weaning process. RESULTS: We studied 252 patients with a median mechanical ventilation time of 3.7 days (interquartile range of 1 to 23 days), a rapid shallow breathing index value of 48 (median), a maximum inspiratory pressure of 40 cmH2O, and a maximum expiratory pressure of 40 cm H2O (median). Of these 252 patients, 32 (12.7%) had to be reintubated, which represented weaning failure. Noninvasive ventilation was used postextubation in 170 (73%) patients, and 15% of these patients were reintubated, which also represented weaning failure. The mortality rate of the 252 patients studied was 8.73% (22), and there was no significant difference in the age, gender, mechanical ventilation time, and maximum inspiratory pressure between the survivors and nonsurvivors. CONCLUSIONS: The use of a specific weaning protocol resulted in a lower mechanical ventilation time and an acceptable reintubation rate. This protocol can be used as a comparative index in hospitals to improve the weaning system, its monitoring and the informative reporting of patient outcomes and may represent a future tool and source of quality markers for patient care.

Dexmedetomidine versus standard care sedation with propofol or midazolam in intensive care: an economic evaluation.

INTRODUCTION Dexmedetomidine was shown in two European randomized double-blind double-dummy trials (PRODEX and MIDEX) to be non-inferior to propofol and midazolam in maintaining target sedation levels in mechanically ventilated intensive care unit (ICU) patients. Additionally, dexmedetomidine shortened the time to extubation versus both standard sedatives, suggesting that it may reduce ICU resource needs and thus lower ICU costs. Considering resource utilization data from these two trials, we performed a secondary, cost-minimization analysis assessing the economics of dexmedetomidine versus standard care sedation. METHODS The total ICU costs associated with each study sedative were calculated on the basis of total study sedative consumption and the number of days patients remained intubated, required non-invasive ventilation, or required ICU care without mechanical ventilation. The daily unit costs for these three consecutive ICU periods were set to decline toward discharge, reflecting the observed reduction in mean daily Therapeutic Intervention Scoring System (TISS) points between the periods. A number of additional sensitivity analyses were performed, including one in which the total ICU costs were based on the cumulative sum of daily TISS points over the ICU period, and two further scenarios, with declining direct variable daily costs only. RESULTS Based on pooled data from both trials, sedation with dexmedetomidine resulted in lower total ICU costs than using the standard sedatives, with a difference of €2,656 in the median (interquartile range) total ICU costs-€11,864 (€7,070 to €23,457) versus €14,520 (€7,871 to €26,254)-and €1,649 in the mean total ICU costs. The median (mean) total ICU costs with dexmedetomidine compared with those of propofol or midazolam were €1,292 (€747) and €3,573 (€2,536) lower, respectively. The result was robust, indicating lower costs with dexmedetomidine in all sensitivity analyses, including those in which only direct variable ICU costs were considered. The likelihood of dexmedetomidine resulting in lower total ICU costs compared with pooled standard care was 91.0% (72.4% versus propofol and 98.0% versus midazolam). CONCLUSIONS From an economic point of view, dexmedetomidine appears to be a preferable option compared with standard sedatives for providing light to moderate ICU sedation exceeding 24 hours. The savings potential results primarily from shorter time to extubation. TRIAL REGISTRATION ClinicalTrials.gov NCT00479661 (PRODEX), NCT00481312 (MIDEX).

Increase in particle number emissions from motor vehicles due to interruption of steady traffic flow

We assess the increase in particle number emissions from motor vehicles driving at steady speed when forced to stop and accelerate from rest. Considering the example of a signalized pedestrian crossing on a two-way single-lane urban road, we use a complex line source method to calculate the total emissions produced by a specific number and mix of light petrol cars and diesel passenger buses and show that the total emissions during a red light is significantly higher than during the time when the light remains green. Replacing two cars with one bus increased the emissions by over an order of magnitude. Considering these large differences, we conclude that the importance attached to particle number emissions in traffic management policies be reassessed in the future.

Bushfire responsive architecture : strategies for reconciling bushfire and biodiversity with daily life

My perspective on the problems associated with building in bushfire prone landscapes comes from 12 years of study of the biophysical and cultural landscapes in the Great Southern Region of WA which resulted in the design and construction of the ‘Hhouse’ at Bremer Bay. The house was developed using a ‘ground up’ approach whereby I conducted a topographical survey and worked with a local botanist and a bushfire risk consultant to ascertain the level of threat that fire presented to this particular site. My intention from the outset however, was not to design a bushfire resistant house per se, but to develop a design which would place the owners in close proximity to the highly biodiverse heath vegetation of the site. I was also seeking a means—through architectural design—of linking the patterns of usage of the house with other site specific conditions related to the prevailing winds, solar orientation and seasonal change.

Improved functional ability and independence in activities of daily living for older adults at high risk of hospital readmission : a randomised controlled trial

Objective: During hospitalisation older people often experience functional decline which impacts on their future independence. The objective of this study was to evaluate a multifaceted transitional care intervention including home-based exercise strategies for at-risk older people on functional status, independence in activities of daily living, and walking ability. Methods: A randomised controlled trial was undertaken in a metropolitan hospital in Australia with 128 patients (64 intervention, 64 control) aged over 65 years with an acute medical admission and at least one risk factor for hospital readmission. The intervention group received an individually tailored program for exercise and follow-up care which was commenced in hospital and included regular visits in hospital by a physiotherapist and a Registered Nurse, a home visit following discharge, and regular telephone follow-up for 24 weeks following discharge. The program was designed to improve health promoting behaviours, strength, stability, endurance and mobility. Data were collected at baseline, then 4, 12 and 24 weeks following discharge using the Index of Activities of Daily Living (ADL), Instrumental Index of Activities of Daily Living (IADL), and the Walking Impairment Questionnaire (Modified). Results: Significant improvements were found in the intervention group in IADL scores (p<.001), ADL scores (p<.001), and WIQ scale scores (p<.001) in comparison to the control group. The greatest improvements were found in the first four weeks following discharge. Conclusions: Early introduction of a transitional model of care incorporating a tailored exercise program and regular telephone follow-up for hospitalised at-risk older adults can improve independence and functional ability.