Technology in ICU plays a critical role in ensuring patient safety. In particular, mechanical ventilation can be a lifesaving intervention. While advances in technologies have increased the safety and performance of ventilators, mechanical ventilation is not without risk. The issue of sedation management is especially important for mechanically ventilated patients.
The Issue
Patient discomfort in the ICU is not an uncommon issue. Mechanically ventilated patients cannot easily communicate, are often hooked up to machines that provide life-sustaining support and are dependent on clinicians to attend to their care and comfort. As many as 71 percent of patients in the ICU show signs of agitation at least once during their hospitalization.1 Ventilation can also be an uncomfortable experience due to the invasiveness of the tubing, and mismatches (or “asynchronies”) between the patient’s demand for breath and the ventilator-delivered breathing pattern.2 To ease distress, medical professionals may sedate patients, particularly those on mechanical ventilation, to make them more comfortable during breath support and other interventions.
If not carefully managed, liberal use of sedation can extend the length of time a patient is on a ventilator1 as well as increase the risk of complications.2 A growing body of research has confirmed a strong link between oversedation and poor patient outcomes.1 In addition, patients on prolonged mechanical ventilation are at increased risk of developing hospital-acquired infections (e.g., ventilator-associated pneumonia and other ventilator-acquired conditions), impaired pulmonary function and quality of life, and even mortality.3 Ventilator-patient asynchrony has also been associated with increased time on mechanical ventilation and other poor outcomes.4 However, there are resources and technology available to clinicians that can potentially help with the detection and resolution of patient- ventilator asynchrony, that could improve patient comfort and well-being, lead to decreased use of sedation.
Sedation Management
Ventilator setting changes are an alternative asynchrony management technique that may be preferable to sedation. In response to asynchrony, clinicians can adjust ventilator settings in any number of ways, depending on which type of asynchrony is present. Such modification to ventilator settings might include changing the mode from a controlled to a spontaneous breathing mode or altering the inspiratory timing or ending of the breath cycle. Any of these modifications might limit the risk of ventilator-induced lung injury and overuse of sedatives and analgesics.5 Despite having this non-pharmacologic option, a recent study showed that clinicians chose to treat asynchrony by adjusting ventilator settings in only about 50 percent of the cases, even though this intervention had a significantly greater impact on decreasing asynchrony than did increasing sedation/analgesia.5
A ventilation mode that has been shown to decrease the incidence of patient ventilator asynchrony is Proportional Assist Ventilation Plus (PAV+) software, a spontaneous breath type in which the ventilator supports the patient breathing in proportion to their effort. This mode allows the patient to help dictate all segments of the breath and may reduce instances of the patient “fighting” the ventilator. Several studies have shown that PAV+ technology significantly decreases patient-ventilator asynchrony.6-8
Spontaneous breathing trials (SBTs), given intermittently to determine patient readiness for discontinuation of mechanical ventilation, may also shorten time on mechanical ventilation and improve outcomes.9-13 SBTs can help predict whether patients are ready to breathe on their own13 and should be given early and frequently in a hospital stay to improve patients’ chances of early liberation from MV. In conjunction with good sedation management, SBTs can help return patients to unsupported breathing sooner, potentially reducing the risks and discomfort of prolonged mechanical ventilation.9,10
In addition, daily breaks from sedative infusions have been shown to decrease mortality and shorten hospital stays.14-16 Studies have shown that both lighter sedation and daily sedation holidays for mechanically ventilated patients lower the risk of mortality and complications, such as drug-induced delirium or ventilator-associated pneumonia.14-17 Sedation holidays can help avoid drug accumulation and oversedation.16 They may allow a patient time to reorient, and even reduce psychological trauma from critical care stresses.18 Finally, they may provide clinicians with an important opportunity to assess a patient’s neurological and respiratory status,13 as well as his readiness to be weaned from sedation and mechanical ventilation.9,10,16
Oversedation can affect not only patient outcomes, but also hospital resources. Complications from oversedation can also lead to the overtaxing of ICU personnel and equipment. Better sedation management will help ensure that ICU resources are more readily available for incoming critical patients.
It is critically important for clinicians to evaluate the patient condition and consider all treatment methods before resorting to sedation to ease patient distress. By appropriately managing patient discomfort and carefully considering when and why sedation is used, unnecessary sedation may be avoided.19
Korinne Jew is medical affairs manager for Covidien Respiratory & Monitoring Solutions, Boulder, Col.
References
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