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Definition and Techniques for Spontaneous Awakening (SAT) and
Spontaneous Breathing Trial (SBT) Protocol
Introduction - Reducing the number of days a patient is on mechanical ventilation has been shown to
reduce the risk of VAP. (Brook et al., 1999; Ely et al., 2001; Ely et al., 2003; J. Kress, Pohlman, O'Connor,
& Hall, 2000) Strategies for weaning patients off of mechanical ventilation often include a spontaneous
awakening (SAT) and spontaneous breathing trials (SBT). A wake up and breathe protocol using both the
SAT and SBT together, rather than separately can significantly reduce the number of days patients are
on mechanical ventilation. Girard et. al. (Girard et al., 2008) showed that paired, the SAT and SBT
reduced the number of days patients were on mechanical ventilation (3.1 mean difference, 95% CI 0.75.6; p=0.02), with a concomitant reduction in the length of hospital stay (4 day difference) when
compared to SBT alone. This same technique, often called a readiness-to-wean or sedation protocol,
has been used in other institutions with much success. (Blackwood et al., 2011; J. Kress, Pohlman,
O'Connor, & Hall, 2000; Quenot et al., 2007) We are using the model Girard et. al. developed in 2008 for
this project.
SAT safety Screen and Spontaneous Awakening Trial (SAT)
The SAT consists of two parts, a safety screen and the SAT. (Please see Figure 1 below) Often times this
is done by the bedside nurse or respiratory therapist in the early morning. The safety screen attempts to
assure the trials will not be used when contraindicated. Patients pass the screen unless:
1.
2.
3.
4.
5.
They are receiving a sedative infusion for active seizures or alcohol withdrawal
They are receiving escalating doses of sedative for agitation
They are receiving neuromuscular blockers
They have evidence of active myocardial ischemia in prior 24 hours
They have evidence of increased intracranial pressure
If the patient passes the safety screen, they proceed to have a SAT. For the SAT, all sedatives and
analgesics used for sedation are stopped. Analgesics used for pain are continued. The goal is that the
patient can open their eyes to verbal stimuli or can go without sedation for 4 hours or more without the
following:
1.
2.
3.
4.
5.
6.
7.
sustained anxiety
agitation
pain
a respiratory rate of 35 breaths/minute for >= 5 minutes
an SpO2 of less than 88% for >=5 minutes
an acute cardiac dysrhythmia
two or more signs of respiratory distress
a. tachycardia
b. bradycardia
c. use of accessory muscles
CSTS –Appendix K: Definition and Technique for SAT and SBT Protocol
© Armstrong Institute for Patient Safety and Quality, Johns Hopkins Medicine
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SAT and SBT –Def-Tech
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d. abdominal paradox
e. diaphoresis
f. marked dyspnea
If a patient fails the SAT, sedatives are started at one half the prior dosage and titrated up as needed.
Safety Screen and Spontaneous Breathing Trial (SBT)
If a patient passes the SAT, the patient is assessed for the SBT safety screen. Patients pass if:
1.
2.
3.
4.
5.
they have adequate oxygenation (SpO2 >=88% on an F1O2 of <=50% and a PEEP <=8 cm H2O)
any spontaneous inspiratory effort in a 5-min period
no agitation
no significant use of vasopressors or inotropes
no evidence of increased intracranial pressure
If a patient fails, he is reassessed for SAT the following day. If the patient passes, they undergo the SBT.
For the SBT, ventilatory support is removed and the patient is allowed to breathe for 120 minutes
through either a T-tube circuit of a ventilatory circuit with CPAP of 5cm H2O or pressure support
ventilation of less than 7cm H2O. Patients pass the SBT if they don’t develop any of the following failure
criteria:
1.
2.
3.
4.
5.
respiratory rate of more than 35 or less that 8 breaths per min for 5 min or longer
hypoxemia (SpO2 < 88% for >=5 min)
abrupt change in mental status
an acute cardiac arrhythmia
two or more signs of respiratory distress
a. tachycardia
b. bradycardia
c. use of accessory muscles
d. abdominal paradox
e. diaphoresis
f. marked dyspnea
If a patient fails the SBT, he is reassessed for SAT the following day. If a patient passes, the patient’s
physicians are notified for possible extubation.
Measuring Compliance with SAT and SBT for this Project
The above protocol is adapted from “Efficacy and safety of a paired sedation and ventilator weaning
protocol on the duration of mechanical ventilation,” by Girard et. al. (2008). While this approach was
found to be very effective as a research protocol, it may be challenging to measure compliance with this
approach in our ICUs.
CSTS –Appendix K: Definition and Technique for SAT and SBT Protocol
© Armstrong Institute for Patient Safety and Quality, Johns Hopkins Medicine
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A more practical approach to measuring the SAT and SBT is described below. Lets start with measuring
SAT using 3 steps (Figure 2).
Step 1. We start with the question, “Is the patient responsive to verbal stimuli?” If the answer is yes,
they have already “passed” the SAT. If the answer is no, then the healthcare provider needs to assess
the appropriateness of an SAT.
Step 2. “Has the patient received any medication for sedation?” Sedative medications for this purpose
include: Lorazepam, Midasolam, Propofol, Fentanyl, Morphine, Demorol, Dilaudid, Haldol and Precedex.
If the patient is not receiving medication for sedation, the reason this patient is not responsive is not
related to sedation medication and an SAT is not warranted. An “NI” would be entered when this is the
case. If the patient is receiving sedation medication, then the healthcare provider needs to continue to
assess the appropriateness of an SAT.
Step 3. “Have medications for sedation been held during the past 24 hours?” If the answer is yes, then
the SAT has been performed, whether or not there has been any “formal” trial. If the answer is no, then
the patient may be eligible for an SAT; the SAT Safety Screen would need to be performed first.
If the patient cannot pass the safety screen, then he is reevaluated in 24 hours. If he passes the screen,
he goes on to the SAT itself. The SAT safety screen and SAT are described both in the text above and in
the flow diagram itself. If the patient passes the SAT, he can go on to the SBT safety screen. If the
patient does not pass the SAT, sedation should be cut to ½ original dosage and titrated up for pain
control and agitation.
While implementing SAT and SBT are best done together, we will be measuring the two concepts
independently. Both the SBT safety screen and the SBT itself are described in the text above and in the
flow diagram below.
The SBT safety screen should only be performed after the patient passes the SAT. The patient passes
the screen if they meet the criteria listed. If the patient does not pass the screen, he is still marked “Y”
as having an SBT. If the patient passes, he goes on to the SBT. An “N” would only be noted if the
patient did not have an SBT safety screen or an SBT
If the patient has an SBT, whether or not he passes, he is marked as “Y” in that column and can be
considered for extubation. If he does not pass, his ventilation status is returned to his baseline (before
the trial) and he should start at the question: “Is the patient responsive to verbal stimuli?” 24 hours
later.
CSTS –Appendix K: Definition and Technique for SAT and SBT Protocol
© Armstrong Institute for Patient Safety and Quality, Johns Hopkins Medicine
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Figure 1. Spontaneous Awakening (SAT) and Spontaneous Breathing Trial (SBT)
Protocol.
CSTS –Appendix K: Definition and Technique for SAT and SBT Protocol
© Armstrong Institute for Patient Safety and Quality, Johns Hopkins Medicine
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Figure 2. Measuring Compliance with SAT for this project.
CSTS –Appendix K: Definition and Technique for SAT and SBT Protocol
© Armstrong Institute for Patient Safety and Quality, Johns Hopkins Medicine
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References
Blackwood, B., Alderdice, F., Burns, K., Cardwell, C., Lavery, G., & O'Hallaran, P. (2011). Use
of weaning protocols for reducing duration of mechancal ventilatoin in critically ill adult
patients: Cochran systematic review and meta-analysis. BMJ, Jan 13
Brook, A. D., Ahrens, T. S., Schaiff, R., Prentice, D., Sherman, G., Shannon, W., et al. (1999).
Effect of a nursing-implemented sedation protocol on the duration of mechanical
ventilation. Critical Care Medicine, 27(12), 2609-2615.
Ely, E. W., Meade, M. O., Haponik, E. F., Kollef, M. H., Cook, D. J., Guyatt, G. H., et al.
(2001). Mechanical ventilator weaning protocols driven by nonphysician health-care
professionals: Evidence-based clinical practice guidelines. Chest, 120(6 Suppl), 454S-63S.
Ely, E. W., Truman, B., Shintani, A., Thomason, J. W., Wheeler, A. P., Gordon, S., et al. (2003).
Monitoring sedation status over time in ICU patients: Reliability and validity of the
richmond agitation-sedation scale (RASS). JAMA : The Journal of the American Medical
Association, 289(22), 2983-2991.
Girard, T. D., Kress, J. P., Fuchs, B. D., Thomason, J. W., Schweickert, W. D., Pun, B. T., et al.
(2008). 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. Lancet, 371(9607), 126-134.
Kress, J., Pohlman, A., O'Connor, M., & Hall, J. (2000). Daily interruption of sedative infusion
in critically ill undergoing mechanical ventilation. N.Engl.J.Med., 342, 1471-1477.
Quenot, J., Ladoire, S., Devoucoux, F., Doise, J., Cailliod, R., Cunin, N., et al. (2007). Effect of
a nurse-implemented sedation protocl on the incidence of ventilator associate penumonia.
Crit Care Med, 35(9), 2031-9.
CSTS –Appendix K: Definition and Technique for SAT and SBT Protocol
© Armstrong Institute for Patient Safety and Quality, Johns Hopkins Medicine
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