Conservative oxygen therapy in mechanically ventilated patients following cardiac arrest: a retrospective nested cohort study

Background: In mechanically ventilated (MV) cardiac arrest (CA) survivors admitted to the intensive care unit (ICU) avoidance of hypoxia is considered crucial. However, avoidance of hyperoxia may also be important. A conservative approach to oxygen therapy may reduce exposure to both. Methods: We evaluated the introduction of conservative oxygen therapy (target SpO2 88-92% using the lowest FiO2) during MV for resuscitated CA patients admitted to the ICU. Results: We studied 912 arterial blood gas (ABG) datasets: 448 ABGs from 50 'conventional' and 464 ABGs from 50 'conservative' oxygen therapy patients. Compared to the conventional group, conservative group patients had significantly lower PaO2 values and FiO2 exposure (p <0.001, respectively); more received MV in a spontaneous ventilation mode (18% vs 2%; p =0.001) and more were exposed to a FiO 2 of 0.21 (19 vs 0 patients, p =0.001). Additionally, according to mean PaO2, more conservative group patients were classified as normoxaemic (36 vs 16 patients, p <0.01) and fewer as hyperoxaemic (14 vs 33 patients, p <0.01). Finally, ICU length of stay was significantly shorter for conservative group patients (p =0.04). There was no difference in the proportion of survivors discharged from hospital with good neurological outcome (14/23 vs 12/22 patients, p =0.67). Conclusions: Our findings provide preliminary support for the feasibility and physiological safety of conservative oxygen therapy in patients admitted to ICU for MV support after cardiac arrest (Trial registration, NCT01684124).

Trajectory of sedation assessment and sedative use in intubated and ventilated patients in intensive care: a clinical audit

Background: Sedation is crucial for the recovery of patients in intensive care units (ICUs). Maintaining comfort and safety promotes optimal care for critically ill patients. Purpose: To examine sedation assessment and management undertaken by health professionals for mechanically ventilated patients in one Australian ICU. Methods: A retrospective clinical audit was undertaken of medical records of all eligible, mechanically ventilated patients admitted to an ICU of an Australian metropolitan, teaching hospital over a 12-month period. A Sedation Audit Tool was used to collect data from the day of intubation to 5 days after intubation. Findings: Data were extracted from medical records of 150 patients. The Riker Sedation-Agitation Scale (SAS) was the scoring system used. Patients were unarousable or very sedated between 57% and 81% at some point during the study period, while between 5% and 11% were agitated, very agitated or extremely agitated across this time. Patients' sedation scores were not documented in between 3.3% and 23.3% of patients. Medications commonly used were propofol, midazolam, morphine, and fentanyl. There were 135 situations of adverse events, which related to patients pulling endotracheal tubes leading to malpositioning, patients biting endotracheal tubes causing desaturation, patient experiencing excessive agitation requiring restraint use, patients experiencing increased intracranial pressure above desired limits, patients self-extubating, and patients experiencing over-drowsiness leading to delays in extubation. Conclusions: Many patients were either very sedated or agitated at some point during the study period, and some patients experienced adverse outcomes associated with sedation practices. The findings inform future quality initiatives to improve sedation practices.

Sedation and analgesia management for mechanically ventilated adults: literature review, case study and recommentations for practice.

The quality of sedation management in mechanically ventilated patients has been a source of concern in recent years. This paper summarises the literature on the principles of optimal sedation, discusses the consequences of over and undersedation, highlighting the importance of appropriate pain management, and presents a case study using the results of an audit of 48 mechanically ventilated adults. As a result of the review and audit, we are implementing changes to practice.

The most important recommendations from the literature are the use of a sedation scale, setting of a goal sedation score, appropriate pain management and implementation of a nurse initiated sedation algorithm. Other recommendations include use of bolus rather than continuous sedative infusions and recommencing regular medications for anxiety, depression and other phychiatric disorders as soon as possible. A recommendation arising from our audit was the need to identify patients at high risk of oversedation and undersedation and adopt a proactive rather than reactive approach to management. The practice goal is to provide adequate and appropriate analgesia and anxiolysis for patients. This will improve patient comfort while reducing length of mechanical ventilation and minimising risk of complications.

Lateral positioning for critically ill adult patients

BACKGROUND: Critically ill patients require regular body position changes to minimize the adverse effects of bed rest, inactivity and immobilization. However, uncertainty surrounds the effectiveness of lateral positioning for improving pulmonary gas exchange, aiding drainage of tracheobronchial secretions and preventing morbidity. In addition, it is unclear whether the perceived risk levied by respiratory and haemodynamic instability upon turning critically ill patients outweighs the respiratory benefits of side-to-side rotation. Thus, lack of certainty may contribute to variation in positioning practice and equivocal patient outcomes. OBJECTIVES: To evaluate effects of the lateral position compared with other body positions on patient outcomes (mortality, morbidity and clinical adverse events) in critically ill adult patients. (Clinical adverse events include hypoxaemia, hypotension, low oxygen delivery and global indicators of impaired tissue oxygenation.) We examined single use of the lateral position (i.e. on the right or left side) and repeat use of the lateral position (i.e. lateral positioning) within a positioning schedule. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 5), MEDLINE (1950 to 23 May 2015), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1937 to 23 May 2015), the Allied and Complementary Medicine Database (AMED) (1984 to 23 May 2015), Latin American Caribbean Health Sciences Literature (LILACS) (1901 to 23 May 2015), Web of Science (1945 to 23 May 2015), Index to Theses in Great Britain and Ireland (1950 to 23 May 2015), Trove (2009 to 23 May 2015; previously Australasian Digital Theses Program (1997 to December 2008)) and Proquest Dissertations and Theses (2009 to 23 May 2015; previously Proquest Digital Dissertations (1980 to 23 May 2015)). We handsearched the reference lists of potentially relevant reports and two nursing journals. SELECTION CRITERIA: We included randomized and quasi-randomized trials examining effects of lateral positioning in critically ill adults. We included manual or automated turns but limited eligibility to studies that included duration of body position of 10 minutes or longer. We examined each lateral position versus at least one comparator (opposite lateral position and/or another body position) for single therapy effects, and the lateral positioning schedule (repeated lateral turning) versus other positioning schedules for repetitive therapy effects. DATA COLLECTION AND ANALYSIS: We pre-specified methods to be used for data collection, risk of bias assessment and analysis. Two independent review authors carried out each stage of selection and data extraction and settled differences in opinion by consensus, or by third party adjudication when disagreements remained unresolved. We planned analysis of pair-wise comparisons under composite time intervals with the aim of considering recommendations based on meta-analyses of studies with low risk of bias. MAIN RESULTS: We included 24 studies of critically ill adults. No study reported mortality as an outcome of interest. Two randomized controlled trials (RCTs) examined lateral positioning for pulmonary morbidity outcomes but provided insufficient information for meta-analysis. A total of 22 randomized trials examined effects of lateral positioning (four parallel-group and 18 cross-over designs) by measuring various continuous data outcomes commonly used to detect adverse cardiopulmonary events within critical care areas. However, parallel-group studies were not comparable, and cross-over studies provided limited data as the result of unit of analysis errors. Eight studies provided some data; most of these were single studies with small effects that were imprecise. We pooled partial pressure of arterial oxygen (PaO2) as a measure to detect hypoxaemia from two small studies of participants with unilateral lung disease (n = 19). The mean difference (MD) between lateral positions (bad lung down versus good lung down) was approximately 50 mmHg (MD -49.26 mmHg, 95% confidence interval (CI) -67.33 to -31.18; P value < 0.00001). Despite a lower mean PaO2 for bad lung down, hypoxaemia (mean PaO2 < 60 mmHg) was not consistently reported. Furthermore, pooled data had methodological shortcomings with unclear risk of bias. We had similar doubts regarding internal validity for other studies included in the review. AUTHORS' CONCLUSIONS: Review authors could provide no clinical practice recommendations based on the findings of included studies. Available research could not eliminate the uncertainty surrounding benefits and/or risks associated with lateral positioning of critically ill adult patients. Research gaps include the effectiveness of lateral positioning compared with semi recumbent positioning for mechanically ventilated patients, lateral positioning compared with prone positioning for acute respiratory distress syndrome (ARDS) and less frequent changes in body position. We recommend that future research be undertaken to address whether the routine practice of repositioning patients on their side benefits all, some or few critically ill patients.

A randomized trial of protocol-directed sedation management for mechanical ventilation in an Australian intensive care unit

Objective: To compare protocol-directed sedation management with traditional non-protocol-directed practice in mechanically ventilated patients. Design: Randomized, controlled trial. Setting: General intensive care unit (24 beds) in an Australian metropolitan teaching hospital. Patients: Adult, mechanically ventilated patients (n = 312). Interventions: Patients were randomly assigned to receive sedation directed by formal guidelines (protocol group, n = 153) or usual local clinical practice (control, n = 159). Measurements and Main Results: The median (95% confidence interval) duration of ventilation was 79 hrs (56-93 hrs) for patients in the protocol group compared with 58 hrs (44-78 hrs) for patients who received control care (p = .20). Lengths of stay (median [range]) in the intensive care unit (94 [2-1106] hrs vs. 88 (14-962) hrs, p = .58) and hospital (13 [1-113] days vs. 13 (1-365) days, p = .97) were similar, as were the proportions of subjects receiving a tracheostomy (17% vs. 15%, p = .64) or undergoing unplanned self-extubation (1.3% vs. 0.6%, p = .61). Death in the intensive care unit occurred in 32 (21%) patients in the protocol group and 32 (20%) control subjects (p = .89), with a similar overall proportion of deaths in hospital (25% vs. 22%, p = .51). A Cox proportional hazards model, after adjustment for age, gender, Acute Physiology and Chronic Health Evaluation II score, diagnostic category, and doses of commonly used drugs, estimated that protocol sedation management was associated with a 22% decrease (95% confidence interval 40% decrease to 2% increase, p = .07) in the occurrence of successful weaning from mechanical ventilation. Conclusions: This randomized trial provided no evidence of a substantial reduction in the duration of mechanical ventilation or length of stay, in either the intensive care unit or the hospital, with the use of protocol-directed sedation compared with usual local management. Qualified high-intensity nurse staffing and routine Australian intensive care unit nursing responsibility for many aspects of ventilatory practice may explain the contrast between these findings and some recent North American studies. (C) 2008 Lippincott Williams & Wilkins, Inc.

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.

Patient comfort in the intensive care unit : a multicentre, binational point prevalence study of analgesia, sedation and delirium management

Objective: To measure the prevalence of assessment and management practices for analgesia, sedation and delirium in patients in Australian and New Zealand intensive care units.
Materials and Methods: We developed survey items from a modified Delphi panel and included them in a binational, point prevalence study. We used a standard case report form to capture retrospective patient data on management of analgesia, sedation and delirium at the end of a 4-hour period on the study day. Other data were collected during independent assessment of patient status and medication requirements.
Results: Data were collected on 569 patients in 41 ICUs. Pain assessment was documented in the 4 hours before study observation in 46% of patients. Of 319 assessable patients, 16% had moderate pain and 6% had severe pain. Routine sedation assessment using a scale was recorded in 63% of intubated and ventilated patients. When assessed, 38% were alert and calm, or drowsy and rousable, 22% were lightly to moderately sedated, 31% were deeply sedated (66% of these had a documented indication), and 9% were agitated or restless. Sedatives were titrated to a target level in 42% of patients. Routine assessment of delirium occurred in 3%, and at study assessment 9% had delirium. Wrist or arm restraints were used for 7% of patients.
Conclusions: Only two-thirds of sedated patients had their sedation levels formally assessed, half had pain assessed and very few had formal assessment of delirium. Our description of current practices, and other observational data, may help in planning further research in this area.

A review of sedation scales for the cardiac catheterization laboratory.

Sedation scales have the potential to facilitate effective procedural sedation and analgesia in the cardiac catheterization laboratory (CCL). For this potential to become realized, a scale that is suitable for use in the CCL either needs to be identified or developed.

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

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 (I2 = 86%, P value = 0.008), ICU length of stay (I2 = 82%, P value = 0.02) and incidence of tracheostomy (I2 = 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.

Changes in oxygenation in mechanically ventilated critically ill patients following hyperbaric treatment

BACKGROUND: Some ventilated intensive care unit (ICU) patients may experience reduced oxygenation following hyperbaric oxygen treatment (HBOT).

METHODS: In a prospective, single-centre, observational study, we documented changes in oxygenation and the need for associated changes in ventilator settings in 25 consecutive, mechanically ventilated ICU patients immediately post-treatment and 1, 2, 3 and 6 hours following 61 HBOT sessions. The primary outcome measure of oxygenation was the ratio of arterial partial pressure of oxygen (P(a)O2) against the level of inspired oxygen (F(i)O2), P(a)O2/F(i)O2.

RESULTS: Following HBOT, the P(a)O2/F(i)O2 ratio decreased by 27% on return to ICU (P < 0.001, 95% confidence intervals (CI) 20.6 to 34.2); 22% at 1 hour post-HBOT (P < 0.001, 95% CI 15.1 to 28.6); and 8% at 2 hours post (P = 0.03, 95% CI 0.8 to 14.4). The ratio showed no significant differences from pre-HBOT at 3 and 6 hours post-HBOT. P(a)O2/F(i)O2 ratio changes necessitated adjustments to ventilation parameters upon return to ICU following 30 of 61 HBOT sessions in 17 out of the 25 patients. The most common ventilation parameter altered was F(i)O2 (n = 20), increased by a mean of +0.17 (95% CI 0.11 to 0.23) above baseline for two hours following HBOT.

CONCLUSIONS: Following HBOT, oxygenation is reduced in a majority of mechanically ventilated ICU patients and requires temporary alterations to mechanical ventilation settings. Further study to identify predictive characteristics and to determine causation for those at risk of needing ventilation alterations is required.

INTroducing a care bundle to prevent pressure injury (INTACT) in at-risk patients: a protocol for a cluster randomised trial

BACKGROUND: Pressure injuries are a significant clinical and economic issue, affecting both patients and the health care system. Many pressure injuries in hospitals are facility acquired, and are largely preventable. Despite growing evidence and directives for pressure injury prevention, implementation of preventative strategies is suboptimal, and pressure injuries remain a serious problem in hospitals. OBJECTIVES: This study will test the effectiveness and cost-effectiveness of a patient-centred pressure injury prevention care bundle on the development of hospital acquired pressure injury in at-risk patients. DESIGN: This is a multi-site, parallel group cluster randomised trial. The hospital is the unit of randomisation. METHODS: Adult medical and surgical patients admitted to the study wards of eight hospitals who are (a) deemed to be at risk of pressure injury (i.e. have reduced mobility), (b) expected to stay in hospital for ≥48h, (c) admitted to hospital in the past 36h; and (d) able to provide informed consent will be eligible to participate. Consenting patients will receive either the pressure injury prevention care bundle or standard care. The care bundle contains three main messages: (1) keep moving; (2) look after your skin; and (3) eat a healthy diet. Nurses will receive education about the intervention. Patients will exit the study upon development of a pressure injury, hospital discharge or 28 days, whichever comes first; transfer to another hospital or transfer to critical care and mechanically ventilated. The primary outcome is incidence of hospital acquired pressure injury. Secondary outcomes are pressure injury stage, patient participation in care and health care costs. A health economic sub-study and a process evaluation will be undertaken alongside the trial. Data will be analysed at the cluster (hospital) and patient level. Estimates of hospital acquired pressure injury incidence in each group, group differences and 95% confidence interval and p values will be reported. DISCUSSION: To our knowledge, this is the first trial of an intervention to incorporate a number of pressure injury prevention strategies into a care bundle focusing on patient participation and nurse-patient partnership. The results of this study will provide important information on the effectiveness and cost-effectiveness of this intervention in preventing pressure injuries in at-risk patients. If the results confirm the utility of the developed care bundle, it could have a significant impact on clinical practice worldwide. TRIAL REGISTRATION: This trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613001343796.

Cerebral oxygenation in mechanically ventilated early cardiac arrest survivors: The impact of hypercapnia

BACKGROUND : Optimal cerebral oxygenation is considered fundamental to cerebral protection in cardiac arrest (CA) patients. Hypercapnia increases cerebral blood flow and may also improve cerebral oxygenation. It is uncertain, however, whether this effect occurs in mechanically ventilated early survivors of CA. METHODS: We enrolled mechanically ventilated resuscitated patients within 36 h of their cardiac arrest. We performed a prospective double cross-over physiological study comparing the impact of normocapnia (PaCO2 35-45 mmHg) vs. mild hypercapnia (PaCO2 45-55 mmHg) on regional cerebral tissue oxygen saturation (SctO2) assessed by near infrared spectroscopy (NIRS).RESULTS: We studied seven adult CA patients with a median time to return of spontaneous circulation of 28 min at a median of 26 h and 30 min after CA. During normocapnia (median EtCO2 of 32 mmHg [30-41 mmHg] and PaCO2 of 37 mmHg [32-45 mmHg]) the median NIRS-derived left frontal SctO2 was 61% [52-65%] and the right frontal SctO2 was 61% [54-68%]. However, during mild hypercapnia (median EtCO2 of 49 mmHg [40-57 mmHg] and PaCO2 of 52 mmHg [43-55 mmHg) the median left frontal SctO2 increased to 69% [59-78%] and the right frontal SctO2 increased to 73% [61-76%])(p = 0.001, for all comparisons). CONCLUSION: During the early post-resuscitation period, in mechanically ventilated CA patients, mild hypercapnia increases cerebral oxygenation as assessed by NIRS. Further investigations of the effect of prolonged mild hypercapnia on cerebral oxygenation and patient outcomes appear justified.