Clinical CareConscious sedation in the critically ill ventilated patient
Introduction
The aim of sedation is to provide comfort and minimize anxiety and other forms of distress. In critically ill patients, failure to provide adequate analgesia and sedation has detrimental physiologic consequences [1], [2]. However, the adverse effects of sedation therapy are noteworthy [3], [4] of which hemodynamic instability, interference with ventilatory weaning, and prolonged stay in the intensive care unit (ICU) are the most relevant. Along with the need to optimize the use of ICU resources, “conscious” sedation is becoming increasingly attractive in the ICU [5], [6], [8], [9], [10]. Guidelines suggest that pharmacologic sedation should be individualized and administered for the shortest possible time at the lowest effective dose [3], [5], [6].
However, the optimal level of sedation is still debated, and most authors aim at a score of 3 to 4 [3] according to the Ramsay Scale [7]. Indeed, De Jonghe et al [11] have recently shown that the use of a sedation algorithm aiming at wakefulness and tolerance to ICU procedures significantly reduces the time spent on mechanical ventilation and length of stay without adverse events.
In a previous study, we demonstrated that after 2 days of ICU stay, enteral sedation with hydroxizine is feasible and effective in ventilated patients [12]. Remarkably, most of these patients were maintained awake despite the high severity of their disease. Because of the potential benefit of a conservative sedation strategy, we analyzed on the whole “ventilated” stay if a conscious level of sedation, defined as a score of 2 on the Ramsay Scale, is consistent with an invasive treatment in critically ill ventilated patients.
Section snippets
Methods
Between September 2000 and July 2001, critically ill patients with at least 4 days of expected ventilatory assistance were prospectively analyzed since ICU admission to evaluate the feasibility and efficacy of enteral sedation with hydroxizine (6-12 mg/(kg·d) in 3 doses) [12].
The daily end point of sedation was decided each morning by the attending physician but could be modified during the day based on clinical grounds. The suggested goal was a score of 2 or 3 according to the Ramsay Scale,
Results
Among the 238 patients admitted to our ICU during the study period, 66 patients received at least 4 days of ventilation. Twenty-four of them were not considered for the study: 10, because the expected period of ventilation was underestimated at ICU admission and the remaining, because of exclusion criteria (<18 years old, neurologic impairment, need for neuromuscular blockade) [12]. Demographic and clinical characteristics of the 42 enrolled patients are illustrated in Table 1. Median ICU
Discussion
Sedation is mandatory in critically ill patients because outcome is negatively affected by anxiety and agitation. The stress response causes increased oxygen consumption, hypercoagulability, immunosuppression, dyssynchronous mechanical ventilation, and inadvertent self-removal of invasive devices [1], [2]. On the other hand, excessive sedation can also lead to dangerous adverse effects (hemodynamic impairment, tachyphylaxis and drug dependence, hepatic and renal damage, etc) and can prolong
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Postoperative delirium: Risk factors, prevention, and treatment
2014, Journal of Cardiothoracic and Vascular AnesthesiaCitation Excerpt :The daily interruption of sedation for an awaking and breathing trial reduced the duration of coma, but it did not lower the incidence or duration of POD.77,78 In contrast, the implementation of the concept of conscious sedation and adequate pain management demonstrated a reduced incidence of POD.79,80 The concept of conscious sedation implied a sedation algorithm based on a score of 2 or 3 according to the Ramsay scale (awake, cooperative, and tranquil patient).79,81
Bias reduction in repeated-measures observational studies by the use of propensity score: The case of enteral sedation for critically ill patients
2012, Journal of Critical CareCitation Excerpt :Other parameters, such as anxiety, pain, and agitation, have not been included in the model, as they were considered outcomes of the comparison. In this specific scenario, we already demonstrated elsewhere [30,31] the feasibility of an enteral sedation strategy for critically ill patients. Here, we found that the use of an enteral sedation approach is at least not different from an intravenous regimen in terms of the overall adequacy of sedation, the average level of pain, anxiety, and agitation; these results were nonetheless achieved at a lower level of sedation and with a significant spare of resources.
Delirium: Clinical approach and prevention
2012, Best Practice and Research: Clinical AnaesthesiologyCitation Excerpt :In particular, as noted above, following this approach, the use of deliriogenic sedatives, such as benzodiazepines (midazolam and lorazepam), should be avoided, in favour of drugs that have been shown to reduce the prevalence of delirium, such as α2 agonists (i.e., dexmedetomedine),6,50–54 or the use of protocols favouring the use only of analgesics (i.e., morphine) for the management of patients undergoing mechanical ventilation.49 The ABCDE approach is part of the new concept of ‘conscious sedation target’56,57 for ICU patients, a significant innovation in the field of ICU care: patients should be kept awake whenever possible, even during the critical phases of illness, as excessive sedative therapy presents several important side effects, among which delirium itself. However, conscious sedation is not yet widely adopted because of the potential risk of self-removal of invasive tools58 and because ICU practitioners are concerned about possible increased workload and stress/discomfort for patients.59
Actigraphic monitoring in critically ill patients: Preliminary results toward an "observation-guided sedation"
2009, Journal of Critical CareCitation Excerpt :As soon as possible after admission in ICU, the actigraph was placed at the dominant wrist of patients, and the right positioning was checked regularly at each nurse shift. Each morning, the staff physician, once the desired level of sedation was established, prescribed the therapy according to the local ICU guidelines on use of sedatives (“awake-sedation” [14] and early use of enteral approach [15]), whereas the nursing staff evaluated subjectively the number of sleeping hours and agitation hours during the day (from 06:00 am to 08:00 pm) and the night (from 08:00 pm to 06:00 am). Agitation and anxiety assessment was based on observation of the following: patient/ventilator asynchrony, restless body movements, tachypnea, rigid limbs, self-extubation risk, and facial expression.