Daily interruption of sedative infusions in critically ill patients

Propofol Associated with a Shorter Duration of Mechanical Ventilation than Scheduled Intermittent Lorazepam: A Database Analysis Using Project Impact

Background:

While one prospective controlled study in medical intensive care unit (ICU) patients demonstrated that sedation with propofol leads to a shorter duration of mechanical ventilation compared with scheduled intermittent intravenous lorazepam, its conclusions may not be applicable to surgical ICU patients and institutions not using daily sedation interruption.

Objective:

To compare the duration of mechanical ventilation between medical and surgical ICU patients receiving propofol versus scheduled intermittent lorazepam in routine clinical practice.

Methods:

Retrospective data (January 2001–December 2005) were obtained from the Project IMPACT database for medical and surgical ICU patients at Tufts-New England Medical Center, a 450 bed academic hospital. These patients had been mechanically ventilated for 24 hours or more and had received 24 hours or more of either propofol or scheduled intermittent lorazepam as the sole sedative. Clinically relevant variables were identified a priori, and their influence on duration of mechanical ventilation was evaluated. Differences in these variables between propofol and scheduled intermittent lorazepam groups within the ICU cohorts were then measured.

Results:

Of 4608 database patients, 287 met criteria. Factors associated with a prolonged duration of mechanical ventilation for the medical ICU cohort included sedation use for 5 or more days (OR 13.8; 95% CI 8.3 to 19.4), narcotic use (OR 7.6; 95% CI 2.3 to 13), and scheduled intermittent lorazepam use (OR 7.0; 95% CI 0.4 to 13.7). For the surgical ICU cohort, these factors included sedation use for 5 or more days (OR 15; 95% CI 11.4 to 19.4), APACHE II (Acute Physiology and Chronic Health Evaluation II) score equal to or greater than 18 (OR 4.1; 95% CI 0.4 to 7.8), and scheduled intermittent lorazepam use (OR 4.0; 95% CI 0.2 to 7.7). Duration of mechanical ventilation was the only variable that differed significantly between propofol and scheduled intermittent lorazepam in both the medical ICU, with a median (range) of 6 (3–12) versus 11 (5–25; p = 0.03), and surgical ICU, with a median of 4 (2–15) versus 9 (4–20; p = 0.001), groups.

Conclusions:

Sedation with propofol in the naturalistic setting appears to be associated with a shorter duration of mechanical ventilation compared with scheduled intermittent lorazepam in both medial and surgical ICU patients when only one sedative drug is used. Data from this uncontrolled observational study are consistent with findings from a randomized clinical trial.

The impact of extended bed rest on the musculoskeletal system in the critical care environment

Prolonged immobility is harmful with rapid reductions in muscle mass, bone mineral density and impairment in other body systems evident within the first week of bed rest which is further exacerbated in individuals with critical illness. Our understanding of the aetiology and secondary consequences of prolonged immobilization in the critically ill is improving with recent and ongoing research to establish the cause, effect, and best treatment options. This review aims to describe the current literature on bed rest models for examining immobilization-induced changes in the musculoskeletal system and pathophysiology of immobilisation in critical illness including examination of intracellular signalling processes involved. Finally, the review examines the current barriers to early activity and mobilization and potential rehabilitation strategies, which are being, investigated which may reverse the effects of prolonged bed rest. Addressing the deleterious effects of immobilization is a major step in treatment and prevention of the public health issue, that is, critical illness survivorship.

Neuromuscular blockade and skeletal muscle weakness in critically ill patients: time to rethink the evidence?

Neuromuscular blocking agents are commonly used in critical care. However, concern after observational reports of a causal relationship with skeletal muscle dysfunction and intensive care-acquired weakness (ICU-AW) has resulted in a cautionary and conservative approach to their use. This integrative review, interpreted in the context of our current understanding of the pathophysiology of ICU-AW and integrated into our current conceptual framework of clinical practice, challenges the established clinical view of an adverse relationship between the use of neuromuscular blocking agents and skeletal muscle weakness. In addition to discussing data, this review identifies potential confounders and alternative etiological factors responsible for ICU-AW and provides evidence that neuromuscular blocking agents may not be a major cause of weakness in a 21st century critical care setting.

[Daily interruption of sedation: always a quality indicator?]

The Spanish Society of Critical Care Medicine (SEMICYUC) has recently published an updated version of Quality Indicators in Critical Care. Daily sedative interruption is included among them. As this practice is controversial, research studies are revised and guidelines for its implementation are proposed.

Sedation and weaning from mechanical ventilation: linking spontaneous awakening trials and spontaneous breathing trials to improve patient outcomes

The use of sedation has long been integrated into critical care. Because pain, discomfort, anxiety, and agitation are commonly experienced by critically ill patients, the use of medications to alleviate and control these symptoms will continue; however, data showing that prolonged use of sedating medications imparts harm to patients obligate physicians to use agents and methods of sedation that minimize these negative side effects. Numerous observational studies and clinical trials have proven that decisions in sedation management play a crucial role in determining outcomes for mechanically ventilated ICU patients, and recent evidence supports the use of protocols that streamline efforts to discontinue sedation and mechanical ventilation in a safe and parallel fashion. Regardless of choice of sedating agent, and even when patient-targeted sedation protocols are used to minimize oversedation, the use of spontaneous awakening trials dramatically improves patient outcomes for critically ill patients. Intensive care physicians must continue to study the delivery of sedation in efforts to maximize patient comfort while minimizing patient harm.

Sedation management in Australian and New Zealand intensive care units: doctors' and nurses' practices and opinions

OBJECTIVE

To explore the use of sedatives and analgesics, tools for scoring level of sedation, sedation and pain protocols, and daily interruptions in sedation in Australian and New Zealand intensive care units and to examine doctors' and nurses' opinions about the sedation management of critically ill patients.

METHODS

A cross-sectional Internet-based survey design was used. In total, 2146 members of professional critical care organizations in Australia and New Zealand were e-mailed the survey during a 4-month period in 2006 through 2007.

RESULTS

Of 348 members (16% response rate) who accessed the survey, 246 (71%) completed all sections. Morphine, fentanyl, midazolam, and propofol were the most commonly used medicines. Newer medicines, such as dexmedetomidine and remifentanil, and inhalant medications, such as nitrous oxide and isoflurane, were rarely used by most respondents. Respondents used protocols to manage sedatives (54%) and analgesics (51%), and sedation assessment tools were regularly used by 72%. A total of 62% reported daily interruption of sedation; 23% used daily interruption for more than 75% of patients. A disparity was evident between respondents' opinions on how deeply patients were usually sedated in practice and how deeply patients should ideally be sedated.

CONCLUSIONS

Newer medications are used much less than are traditional sedatives and analgesics. Sedation protocols are increasingly used in Australasia, despite equivocal evidence supporting their use. Similarly, daily interruption of sedation is common in management of patients receiving mechanical ventilation. Research is needed to explore contextual and personal factors that may affect sedation management.

Sedation and weaning from mechanical ventilation: linking spontaneous awakening trials and spontaneous breathing trials to improve patient outcomes

Liberation from mechanical ventilation is a vital treatment goal in the management of critically ill patients. The duration of mechanical ventilation is affected by strategies for ventilator weaning and sedation. The authors review literature on weaning from mechanical ventilation and delivery of sedation in critically ill patients, including current guidelines recommending the use of spontaneous breathing trials and spontaneous awakening trials. Implementation of these strategies in a wake-up-and-breathe protocol has demonstrated benefit over the use of spontaneous breathing trials alone.

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.

Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial

BACKGROUND

Approaches to removal of sedation and mechanical ventilation for critically ill patients vary widely. Our aim was to assess a protocol that paired spontaneous awakening trials (SATs)-ie, daily interruption of sedatives-with spontaneous breathing trials (SBTs).

METHODS

In four tertiary-care hospitals, we randomly assigned 336 mechanically ventilated patients in intensive care to management with a daily SAT followed by an SBT (intervention group; n=168) or with sedation per usual care plus a daily SBT (control group; n=168). The primary endpoint was time breathing without assistance. Data were analysed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00097630.

FINDINGS

One patient in the intervention group did not begin their assigned treatment protocol because of withdrawal of consent and thus was excluded from analyses and lost to follow-up. Seven patients in the control group discontinued their assigned protocol, and two of these patients were lost to follow-up. Patients in the intervention group spent more days breathing without assistance during the 28-day study period than did those in the control group (14.7 days vs 11.6 days; mean difference 3.1 days, 95% CI 0.7 to 5.6; p=0.02) and were discharged from intensive care (median time in intensive care 9.1 days vs 12.9 days; p=0.01) and the hospital earlier (median time in the hospital 14.9 days vs 19.2 days; p=0.04). More patients in the intervention group self-extubated than in the control group (16 patients vs six patients; 6.0% difference, 95% CI 0.6% to 11.8%; p=0.03), but the number of patients who required reintubation after self-extubation was similar (five patients vs three patients; 1.2% difference, 95% CI -5.2% to 2.5%; p=0.47), as were total reintubation rates (13.8%vs 12.5%; 1.3% difference, 95% CI -8.6% to 6.1%; p=0.73). At any instant during the year after enrolment, patients in the intervention group were less likely to die than were patients in the control group (HR 0.68, 95% CI 0.50 to 0.92; p=0.01). For every seven patients treated with the intervention, one life was saved (number needed to treat was 7.4, 95% CI 4.2 to 35.5).

INTERPRETATION

Our results suggest that a wake up and breathe protocol that pairs daily spontaneous awakening trials (ie, interruption of sedatives) with daily spontaneous breathing trials results in better outcomes for mechanically ventilated patients in intensive care than current standard approaches and should become routine practice.

Delirium and sedation

Critically ill patients nearing the end of life frequently present with needs for aggressive sedation and analgesia. Optimizing patient comfort while permitting effective communication are challenging goals in this patient population. This article discusses delirium and sedation as it applies to dying patients, and provides recommendations for effective management strategies to optimize the experience of such patients at the end of life.