Protocol directed sedation versus non-protocol directed sedation to reduce duration of mechanical ventilation in mechanically ventilated intensive care patients

Protocol-directed sedation versus non-protocol-directed sedation in mechanically ventilated intensive care adults and children

BACKGROUND

The sedation needs of critically ill patients have been recognized as a core component of critical care that is vital to assist recovery and ensure humane treatment. Evidence suggests that sedation requirements are not always optimally managed. Suboptimal sedation, both under- and over-sedation, have been linked to short-term (e.g. length of stay) and long-term (e.g. psychological recovery) outcomes. Strategies to improve sedation assessment and management have been proposed. This review was originally published in 2015 and updated in 2018.

OBJECTIVES

To assess the effects of protocol-directed sedation management compared to usual care on the duration of mechanical ventilation, intensive care unit (ICU) and hospital mortality and other patient outcomes in mechanically ventilated ICU adults and children.

SEARCH METHODS

We used the standard search strategy of the Cochrane Anaesthesia, Critical and Emergency Care Group (ACE). We searched the Cochrane Central Register of Controlled trials (CENTRAL) (December 2017), MEDLINE (OvidSP) (2013 to December 2017), Embase (OvidSP) (2013 to December 2017), CINAHL (BIREME host) (2013 to December 2017), LILACS (2013 to December 2017), trial registries and reference lists of articles. (The original search was run in November 2013).

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-randomized controlled trials conducted in ICUs comparing management with and without protocol-directed sedation in intensive care adults and children.

DATA COLLECTION AND ANALYSIS

Two authors screened the titles and abstracts and then full-text reports identified from our electronic search. We assessed seven domains of potential risk of bias for the included studies. We examined clinical, methodological and statistical heterogeneity and used the random-effects model for meta-analysis where we considered it appropriate. We calculated the mean difference (MD) for duration of mechanical ventilation and risk ratio (RR) for mortality across studies, with 95% confidence intervals (CIs).

MAIN RESULTS

We included four studies with a total of 3323 participants (864 adults and 2459 paediatrics) in this update. Three studies were single-centre, patient-level RCTs and one study was a multicentre cluster-RCT. The settings were in metropolitan centres and included general, mixed medical-surgical, medical only and a range of paediatric units. All four included studies compared the use of protocol-directed sedation, specifically protocols delivered by nurses, with usual care. We rated the risk of selection bias due to random sequence generation low for two studies and unclear for two studies. The risk of bias was highly variable across the domains and studies, with the risk of selection and performance bias generally rated high and the risk of detection and attrition bias generally rated low.When comparing protocol-directed sedation with usual care, there was no clear evidence of difference in duration of mechanical ventilation in hours for the entire duration of the first ICU stay for each patient (MD -28.15 hours, 95% CI -69.15 to 12.84; I² = 85%; 4 studies; adjusted sample 2210 participants; low-quality evidence). There was no clear evidence of difference in ICU mortality (RR 0.77, 95% CI 0.39 to 1.50; I² = 67%; 2 studies; 513 participants; low-quality evidence), or hospital mortality (RR 0.90, 95% CI 0.72 to 1.13; I² = 10%; 3 studies; adjusted sample 2088 participants; low-quality evidence). There was no clear evidence of difference in ICU length of stay (MD -1.70 days, 95% CI-3.71 to 0.31; I² = 82%; 4 studies; adjusted sample of 2123 participants; low-quality of evidence), however there was evidence of a significant reduction in hospital length of stay (MD -3.09 days, 95% CI -5.08 to -1.10; I² = 2%; 3 studies; adjusted sample of 1922 participants; moderate-quality evidence). There was no clear evidence of difference in the incidence of self-extubation (RR 0.88, 95% CI 0.55 to 1.42; I² = 0%; 2 studies; adjusted sample of 1687 participants; high-quality evidence), or incidence of tracheostomy (RR 0.67, 95% CI 0.35 to 1.30; I² = 66%; 3 studies; adjusted sample of 2008 participants; low-quality evidence). Only one study examined incidence of reintubation, therefore we could not pool data; there was no clear evidence of difference (RR 0.65, 95% CI 0.35 to 1.24; 1 study; 321 participants; low-quality evidence).

AUTHORS' CONCLUSIONS

There is currently limited evidence from RCTs evaluating the effectiveness of protocol-directed sedation on patient outcomes. The four included RCTs reported conflicting results and heterogeneity limited the interpretation of results for the primary outcomes of duration of mechanical ventilation and mortality. Further studies, taking into account differing contextual characteristics, are necessary to inform future practice. Methodological strategies to reduce the risk of bias need to be considered in future studies.

Implementation and evaluation of a paediatric nurse-driven sedation protocol in a paediatric intensive care unit

Background

Optimal sedation and analgesia is a challenge in paediatric intensive care units (PICU) because of difficulties in scoring systems and specific metabolism inducing tolerance and withdrawal. Excessive sedation is associated with prolonged mechanical ventilation and hospitalisation. Adult and paediatric data suggest that goal-directed sedation algorithms reduce the duration of mechanical ventilation. We implemented a nurse-driven sedation protocol in a PICU and evaluated its impact.

Methods

We conducted a before and after protocol implementation study in a population of children aged 0–18 years who required mechanical ventilation for at least 24 h between January 2013 and March 2015. After the protocol implementation in January 2014, nurses managed analgesia and sedation following an algorithm that included the COMFORT behaviour scale (COMFORT-B). Duration of mechanical ventilation was the primary outcome; secondary outcomes were total doses and duration of medications, PICU length of stay, incidence of ventilator-associated pneumonia, and occurrence of withdrawal symptoms. Pre–post analysis followed with segmented regression analysis of interrupted time series was used to assess the effect of protocol.

Results

A total of 200 children were analysed, including 107 before implementation and 93 children after implementation of the protocol. After implementation of the protocol, the total number of COMFORT-B scores per day of mechanical ventilation significantly increased from 3.9 ± 2.5 times during the pre-implementation period to 6.6 ± 3.5 times during the post-implementation period (p < 10⁻³). Mean duration of mechanical ventilation tended to be lower in the post-implementation period (8.3 ± 7.3 vs 6.6 ± 5.6 days, p = 0.094), but changes in either the trend per trimester from pre-implementation to post-implementation (p = 0.933) or the immediate change after implementation (p = 0.923) were not significant with segmented regression analysis. No significant change between pre- and post-implementation was shown for total dose of sedatives, withdrawal symptoms, agitation episodes, or unplanned endotracheal extubations.

Conclusions

These results were promising and suggested that implementation of a nurse-driven sedation protocol in a PICU was feasible. Evaluation of sedation and analgesia was better after the protocol implementation; duration of mechanical ventilation and occurrence of withdrawal symptoms tended to be reduced.

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-017-0256-7) contains supplementary material, which is available to authorized users.

Alpha-2 agonists for sedation of mechanically ventilated adults in intensive care units: a systematic review

BACKGROUND

Care of critically ill patients in intensive care units (ICUs) often requires potentially invasive or uncomfortable procedures, such as mechanical ventilation (MV). Sedation can alleviate pain and discomfort, provide protection from stressful or harmful events, prevent anxiety and promote sleep. Various sedative agents are available for use in ICUs. In the UK, the most commonly used sedatives are propofol (Diprivan(®), AstraZeneca), benzodiazepines [e.g. midazolam (Hypnovel(®), Roche) and lorazepam (Ativan(®), Pfizer)] and alpha-2 adrenergic receptor agonists [e.g. dexmedetomidine (Dexdor(®), Orion Corporation) and clonidine (Catapres(®), Boehringer Ingelheim)]. Sedative agents vary in onset/duration of effects and in their side effects. The pattern of sedation of alpha-2 agonists is quite different from that of other sedatives in that patients can be aroused readily and their cognitive performance on psychometric tests is usually preserved. Moreover, respiratory depression is less frequent after alpha-2 agonists than after other sedative agents.

OBJECTIVES

To conduct a systematic review to evaluate the comparative effects of alpha-2 agonists (dexmedetomidine and clonidine) and propofol or benzodiazepines (midazolam and lorazepam) in mechanically ventilated adults admitted to ICUs.

DATA SOURCES

We searched major electronic databases (e.g. MEDLINE without revisions, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE and Cochrane Central Register of Controlled Trials) from 1999 to 2014.

METHODS

Evidence was considered from randomised controlled trials (RCTs) comparing dexmedetomidine with clonidine or dexmedetomidine or clonidine with propofol or benzodiazepines such as midazolam, lorazepam and diazepam (Diazemuls(®), Actavis UK Limited). Primary outcomes included mortality, duration of MV, length of ICU stay and adverse events. One reviewer extracted data and assessed the risk of bias of included trials. A second reviewer cross-checked all the data extracted. Random-effects meta-analyses were used for data synthesis.

RESULTS

Eighteen RCTs (2489 adult patients) were included. One trial at unclear risk of bias compared dexmedetomidine with clonidine and found that target sedation was achieved in a higher number of patients treated with dexmedetomidine with lesser need for additional sedation. The remaining 17 trials compared dexmedetomidine with propofol or benzodiazepines (midazolam or lorazepam). Trials varied considerably with regard to clinical population, type of comparators, dose of sedative agents, outcome measures and length of follow-up. Overall, risk of bias was generally high or unclear. In particular, few trials blinded outcome assessors. Compared with propofol or benzodiazepines (midazolam or lorazepam), dexmedetomidine had no significant effects on mortality [risk ratio (RR) 1.03, 95% confidence interval (CI) 0.85 to 1.24, I (2) = 0%; p = 0.78]. Length of ICU stay (mean difference -1.26 days, 95% CI -1.96 to -0.55 days, I (2) = 31%; p = 0.0004) and time to extubation (mean difference -1.85 days, 95% CI -2.61 to -1.09 days, I (2) = 0%; p < 0.00001) were significantly shorter among patients who received dexmedetomidine. No difference in time to target sedation range was observed between sedative interventions (I (2) = 0%; p = 0.14). Dexmedetomidine was associated with a higher risk of bradycardia (RR 1.88, 95% CI 1.28 to 2.77, I (2) = 46%; p = 0.001).

LIMITATIONS

Trials varied considerably with regard to participants, type of comparators, dose of sedative agents, outcome measures and length of follow-up. Overall, risk of bias was generally high or unclear. In particular, few trials blinded assessors.

CONCLUSIONS

Evidence on the use of clonidine in ICUs is very limited. Dexmedetomidine may be effective in reducing ICU length of stay and time to extubation in critically ill ICU patients. Risk of bradycardia but not of overall mortality is higher among patients treated with dexmedetomidine. Well-designed RCTs are needed to assess the use of clonidine in ICUs and identify subgroups of patients that are more likely to benefit from the use of dexmedetomidine.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014014101.

FUNDING

The National Institute for Health Research Health Technology Assessment programme. The Health Services Research Unit is core funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates.

[A first step towards safer sedation and analgesia: A systematic evaluation of outcomes and level of sedation and analgesia in the mechanically ventilated critically ill patient]

INTRODUCTION

Safe analgesia and sedation strategies are necessary in order to avoid under or over sedation, as well as improving the comfort and safety of critical care patients.

OBJECTIVES

To compare and contrast a multidisciplinary protocol of systematic evaluation and management of analgesia and sedation in a group of critical care patients on mechanical ventilation with the usual procedures.

MATERIALS AND METHODS

A cohort study with contemporary series was conducted in a tertiary care medical-surgical ICU February to November during 2013 and 2014. The inclusion criteria were mechanical ventilation ≥ 24h and use of sedation by continuous infusion. Sedation was monitored using the Richmond agitation-sedation scale or bispectral index, and analgesia were measured using the numeric rating scale, or behavioural indicators of pain scale. The study variables included; mechanical ventilation time, weaning time, ventilation support time, artificial airway time, continuous sedative infusion time, daily dose and frequency of analgesic and sedative drug use, hospital stay, and ICU and hospital mortality, Richmond agitation-sedation scale, bispectral index, numeric rating scale, and behavioural indicators of pain scale measurements. Kruskal Wallis and Chi², and a significance of p<.05 were used.

RESULTS

The study included 153 admissions, 75 pre-intervention and 78 post-intervention, with a mean age of 55.7±13 years old, and 67% men. Both groups showed similarities in age, reason for admission, and APACHE. There were non-significant decreases in mechanical ventilation time 4 (1.4-9.2) and 3.2 (1.4-8.1) days, respectively; p= 0.7, continuous sedative infusion time 6 (3-11) and 5 (3-11) days; p= 0.9, length of hospital stay 29 (18-52); 25 (14-41) days; p= 0.1, ICU mortality (8 vs. 5%; p= 0.4), and hospital mortality (10.6 vs. 9.4%: p= 0.8). Daily doses of midazolam and remifentanil decreased 347 (227-479) mg/day; 261 (159-358) mg/day; p= 0.02 and 2175 (1427-3285) mcg/day; 1500 (715-2740) mcg/day; p= 0.02, respectively. There were increases in the use of remifentanil (32% vs. 51%; p= 0.01), dexmedetomidine (0 vs.6%; p= 0.02), dexketoprofen (60 vs. 76%; p= 0.03), and haloperidol (15 vs.28%; p= 0.04). The use of morphine decreased (71 vs. 54%; p= 0.03). There was an increase in the number of measurements and Richmond agitation-sedation scale scores 6 (3-17); 21 (9-39); p< 0.0001, behavioural indicators of pain scale 6 (3-18); 19(8-33); p< 0.001 and numeric rating scale 4 (2-6); 8 (6-17); p< 0.0001.

CONCLUSIONS

The implementation of a multidisciplinary protocol of systematic evaluation of analgesia and sedation management achieved an improvement in monitoring and adequacy of dose to patient needs, leading to improved outcomes.

Practice guidelines for sedation and analgesia management of critically ill children: a pilot study evaluating guideline impact and feasibility in the PICU

AIMS

The aim of this study was to develop and implement guidelines for sedation and analgesia management in the paediatric intensive care unit (PICU) and evaluate the impact, feasibility and acceptability of these as part of a programme of research in this area and as a prelude to future trial work.

METHOD

This pilot study used a pre-post design using a historical control.

SETTING

Two PICUs at different hospitals in an Australian metropolitan city.

PARTICIPANTS

Patients admitted to the PICU and ventilated for ≥24 h, aged more than 1 month and not admitted for seizure management or terminal care.

INTERVENTION

Guidelines for sedation and analgesia management for critically ill children including algorithm and assessment tools.

OUTCOME VARIABLES

In addition to key outcome variables (ventilation time, medication dose and duration, length of stay), feasibility outcomes data (recruitment, data collection, safety) were evaluated. Guideline adherence was assessed through chart audit and staff were surveyed about merit and the use of guidelines.

RESULTS

The guidelines were trialled for a total of 12 months on 63 patients and variables compared with the historical control group (n=75). Analysis revealed differences in median Morphine infusion duration between groups (pretest 3.63 days (87 h) vs post-test 2.83 days (68 h), p=0.05) and maximum doses (pretest 120 μg/kg/h vs post-test 97.5 μg/kg/h) with no apparent change to ventilation duration. Chart audit revealed varied use of tools, but staff were positive about the guidelines and their use in practice.

CONCLUSIONS

The sedation guidelines impacted on the duration and dosage of agents without any apparent impact on ventilation duration or length of stay. Furthermore, the guidelines appeared to be feasible and acceptable in clinical practice. The results of the study have laid the foundation for follow-up studies in withdrawal from sedation, point prevalence and longitudinal studies of sedation practices as well as drug trial work.

Protocol-directed sedation versus non-protocol-directed sedation to reduce duration of mechanical ventilation in mechanically ventilated intensive care patients

BACKGROUND

The sedation needs of critically ill patients have been recognized as a core component of critical care and meeting these is vital to assist recovery and ensure humane treatment. There is growing evidence to suggest that sedation requirements are not always optimally managed. Sub-optimal sedation incorporates both under- and over-sedation and has been linked to both short-term (e.g. length of stay) and long-term (e.g. psychological recovery) outcomes. Various strategies have been proposed to improve sedation management and address aspects of assessment as well as delivery of sedation.

OBJECTIVES

To assess the effects of protocol-directed sedation management on the duration of mechanical ventilation and other relevant patient outcomes in mechanically ventilated intensive care unit (ICU) patients. We looked at various outcomes and examined the role of bias in order to examine the level of evidence for this intervention.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled trials (CENTRAL) (2013; Issue 11), MEDLINE (OvidSP) (1990 to November 2013), EMBASE (OvidSP) (1990 to November 2013), CINAHL (BIREME host) (1990 to November 2013), Database of Abstracts of Reviews of Effects (DARE) (1990 to November 2013), LILACS (1990 to November 2013), Current Controlled Trials and US National Institutes of Health Clinical Research Studies (1990 to November 2013), and reference lists of articles. We re-ran the search in October 2014. We will deal with any studies of interest when we update the review.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) conducted in adult ICUs comparing management with and without protocol-directed sedation.

DATA COLLECTION AND ANALYSIS

Two authors screened the titles and abstracts and then the full-text reports identified from our electronic search. We assessed seven domains of potential risk of bias for the included studies. We examined the clinical, methodological and statistical heterogeneity and used the random-effects model for meta-analysis where we considered it appropriate. We calculated the mean difference (MD) for duration of mechanical ventilation and risk ratio (RR) for mortality across studies, with 95% confidence intervals (CI).

MAIN RESULTS

We identified two eligible studies with 633 participants. Both included studies compared the use of protocol-directed sedation, specifically protocols delivered by nurses, with usual care. We rated the risk of selection bias due to random sequence generation low for one study and unclear for one study. The risk of selection bias related to allocation concealment was low for both studies. We also assessed detection and attrition bias as low for both studies while we considered performance bias high due to the inability to blind participants and clinicians in both studies. Risk due to other sources of bias, such as potential for contamination between groups and reporting bias, was considered unclear. There was no clear evidence of differences in duration of mechanical ventilation (MD -5.74 hours, 95% CI -62.01 to 50.53, low quality evidence), ICU length of stay (MD -0.62 days, 95% CI -2.97 to 1.73) and hospital length of stay (MD -3.78 days, 95% CI -8.54 to 0.97) between people being managed with protocol-directed sedation versus usual care. Similarly, there was no clear evidence of difference in hospital mortality between the two groups (RR 0.96, 95% CI 0.71 to 1.31, low quality evidence). ICU mortality was only reported in one study preventing pooling of data. There was no clear evidence of difference in the incidence of tracheostomy (RR 0.77, 95% CI 0.31 to 1.89). The studies reported few adverse event outcomes; one study reported self extubation while the other study reported re-intubation; given this difference in outcomes, pooling of data was not possible. There was significant heterogeneity between studies for duration of mechanical ventilation (I(2) = 86%, P value = 0.008), ICU length of stay (I(2) = 82%, P value = 0.02) and incidence of tracheostomy (I(2) = 76%, P value = 0.04), with one study finding a reduction in duration of mechanical ventilation and incidence of tracheostomy and the other study finding no difference.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to evaluate the effectiveness of protocol-directed sedation. Results from the two RCTs were conflicting, resulting in the quality of the body of evidence as a whole being assessed as low. Further studies, taking into account contextual and clinician characteristics in different ICU environments, are necessary to inform future practice. Methodological strategies to reduce the risk of bias need to be considered in future studies.

Alpha-2 agonists for long-term sedation during mechanical ventilation in critically ill patients

BACKGROUND

Sedation reduces patient levels of anxiety and stress, facilitates the delivery of care and ensures safety. Alpha-2 agonists have a range of effects including sedation, analgesia and antianxiety. They sedate, but allow staff to interact with patients and do not suppress respiration. They are attractive alternatives for long-term sedation during mechanical ventilation in critically ill patients.

OBJECTIVES

To assess the safety and efficacy of alpha-2 agonists for sedation of more than 24 hours, compared with traditional sedatives, in mechanically-ventilated critically ill patients.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 10, 2014), MEDLINE (1946 to 9 October 2014), EMBASE (1980 to 9 October 2014), CINAHL (1982 to 9 October 2014), Latin American and Caribbean Health Sciences Literature (1982 to 9 October 2014), ISI Web of Science (1987 to 9 October 2014), Chinese Biological Medical Database (1978 to 9 October 2014) and China National Knowledge Infrastructure (1979 to 9 October 2014), the World Health Organization international clinical trials registry platform (to 9 October 2014), Current Controlled Trials metaRegister of controlled trials active registers (to 9 October 2014), the ClinicalTrials.gov database (to 9 October 2014), the conference proceedings citation index (to 9 October 2014) and the reference lists of included studies and previously published meta-analyses and systematic reviews for relevant studies. We imposed no language restriction.

SELECTION CRITERIA

We included all randomized and quasi-randomized controlled trials comparing alpha-2 agonists (clonidine or dexmedetomidine) versus alternative sedatives for long-term sedation (more than 24 hours) during mechanical ventilation in critically ill patients.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted data. We contacted study authors for additional information. We performed meta-analyses when more than three studies were included, and selected a random-effects model due to expected clinical heterogeneity. We calculated the geometric mean difference for continuous outcomes and the risk ratio for dichotomous outcomes. We described the effects by values and 95% confidence intervals (CIs). We considered two-sided P < 0.05 to be statistically significant.

MAIN RESULTS

Seven studies, covering 1624 participants, met the inclusion criteria. All included studies investigated adults and compared dexmedetomidine with traditional sedatives, including propofol, midazolam and lorazepam. Compared with traditional sedatives, dexmedetomidine reduced the geometric mean duration of mechanical ventilation by 22% (95% CI 10% to 33%; four studies, 1120 participants, low quality evidence), and consequently the length of stay in the intensive care unit (ICU) by 14% (95% CI 1% to 24%; five studies, 1223 participants, very low quality evidence). There was no evidence that dexmedetomidine decreased the risk of delirium (RR 0.85; 95% CI 0.63 to 1.14; seven studies, 1624 participants, very low quality evidence) as results were consistent with both no effect and appreciable benefit. Only one study assessed the risk of coma, but lacked methodological reliability (RR 0.69; 95% CI 0.55 to 0.86, very low quality evidence). Of all the adverse events included, the most commonly reported one was bradycardia, and we observed a doubled (111%) increase in the incidence of bradycardia (RR 2.11; 95% CI 1.39 to 3.20; six studies, 1587 participants, very low quality evidence). Our meta-analysis provided no evidence that dexmedetomidine had any impact on mortality (RR 0.99; 95% CI 0.79 to 1.24; six studies, 1584 participants, very low quality evidence). We observed high levels of heterogeneity in risk of delirium (I² = 70%), but due to the limited number of studies we were unable to determine the source of heterogeneity through subgroup analyses or meta-regression. We judged six of the seven studies to be at high risk of bias.

AUTHORS' CONCLUSIONS

In this review, we found no eligible studies for children or for clonidine. Compared with traditional sedatives, long-term sedation using dexmedetomidine in critically ill adults reduced the duration of mechanical ventilation and ICU length of stay. There was no evidence for a beneficial effect on risk of delirium and the heterogeneity was high. The evidence for risk of coma was inadequate. The most common adverse event was bradycardia. No evidence indicated that dexmedetomidine changed mortality. The general quality of evidence ranged from very low to low, due to high risks of bias, serious inconsistency and imprecision, and strongly suspected publication bias. Future studies could pay more attention to children and to using clonidine

Protocolized versus non-protocolized weaning for reducing the duration of mechanical ventilation in critically ill adult patients

BACKGROUND

This is an update of a review last published in Issue 5, 2010, of The Cochrane Library. Reducing weaning time is desirable in minimizing potential complications from mechanical ventilation. Standardized weaning protocols are purported to reduce time spent on mechanical ventilation. However, evidence supporting their use in clinical practice is inconsistent.

OBJECTIVES

The first objective of this review was to compare the total duration of mechanical ventilation of critically ill adults who were weaned using protocols versus usual (non-protocolized) practice.The second objective was to ascertain differences between protocolized and non-protocolized weaning in outcomes measuring weaning duration, harm (adverse events) and resource use (intensive care unit (ICU) and hospital length of stay, cost).The third objective was to explore, using subgroup analyses, variations in outcomes by type of ICU, type of protocol and approach to delivering the protocol (professional-led or computer-driven).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2014), MEDLINE (1950 to January 2014), EMBASE (1988 to January 2014), CINAHL (1937 to January 2014), LILACS (1982 to January 2014),  ISI Web of Science and ISI Conference Proceedings (1970 to February 2014), and reference lists of articles. We did not apply language restrictions. The original search was performed in January 2010 and updated in January 2014.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs of protocolized weaning versus non-protocolized weaning from mechanical ventilation in critically ill adults.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We performed a priori subgroup and sensitivity analyses. We contacted study authors for additional information.

MAIN RESULTS

We included 17 trials (with 2434 patients) in this updated review. The original review included 11 trials. The total geometric mean duration of mechanical ventilation in the protocolized weaning group was on average reduced by 26% compared with the usual care group (N = 14 trials, 95% confidence interval (CI) 13% to 37%, P = 0.0002). Reductions were most likely to occur in medical, surgical and mixed ICUs, but not in neurosurgical ICUs. Weaning duration was reduced by 70% (N = 8 trials, 95% CI 27% to 88%, P = 0.009); and ICU length of stay by 11% (N = 9 trials, 95% CI 3% to 19%, P = 0.01). There was significant heterogeneity among studies for total duration of mechanical ventilation (I(2) = 67%, P < 0.0001) and weaning duration (I(2) = 97%, P < 0.00001), which could not be explained by subgroup analyses based on type of unit or type of approach.

AUTHORS' CONCLUSIONS

There is evidence of reduced duration of mechanical ventilation, weaning duration and ICU length of stay with use of standardized weaning protocols. Reductions are most likely to occur in medical, surgical and mixed ICUs, but not in neurosurgical ICUs. However, significant heterogeneity among studies indicates caution in generalizing results. Some study authors suggest that organizational context may influence outcomes, however these factors were not considered in all included studies and could not be evaluated. Future trials should consider an evaluation of the process of intervention delivery to distinguish between intervention and implementation effects. There is an important need for further development and research in the neurosurgical population.