Spontaneous Awakening and Breathing Trials Brad Winters MD, PhD March 14, 2013

Spontaneous Awakening and Breathing Trials (SAT &SBT) 2

Spontaneous Awakening and Breathing Trials : VAP Prevention Guidelines Does not specifically address SAT and SBT, however supports weaning. CDC; MMWR Recomm Rep. 2004;53:1-36 Recommends use of daily interruption or lightening of sedation to avoid constant heavy sedation and to facilitate and accelerate weaning. Does not specifically address SBT. ATS/IDSA; AJRCCM 2005;171(4):

Guideline excluded studies that evaluated SAT and SBT. Canadian VAP Prevention Guidelines; J Crit Care 2008;23(1): Recommends the use of combining a daily assessment of readiness wean and daily sedation interruption. SHEA; ICHE 2008;29:S31-S40. 4 Spontaneous Awakening and Breathing Trials : VAP Prevention Guidelines

Spontaneous Awakening Trials Population Medical ICU patients on mechanical ventilation Intervention (RCT) Control group: no interruption (N= 68) Rx group: daily interruption (N= 60) sedation held daily until the patients were awake and could follow instructions or uncomfortable or agitated. All patients received an infusion of morphine for analgesia. Kress et al. NEJM 2000; 342:

Spontaneous Awakening Trials Outcomes 2.4 day reduction duration mechanical ventilation –33% relative risk reduction 3.5 day reduction ICU length of stay –35% relative risk reduction Hospital length of stay unchanged: control group 16.9 days ( days) compared to rx group 13.3 days ( days). Kress et al. NEJM 2000; 342:

Spontaneous Breathing Trials Population Adult medical and coronary ICU patients on mechanical ventilation (n=300) Intervention (RCT) Control group: daily screening (RSBI*) (n=151) Experimental group: daily screening (RSBI) followed by 2-hour SBT (n=149) if they passed the screening test Physicians were notified when their patients successfully completed the trial of spontaneous breathing. *RSBI: rapid shallow breathing index Ely et al. NEJM 1996; 335:

Spontaneous Breathing Trial (SBT) Patient passes SBT safety screen Ventilatory support is removed and the patient is allowed to breathe through either a T-tube circuit or a ventilatory circuit using “flow triggering” (rather than triggering by pressure) with a continuous positive airway pressure of 5 cm of water. No changes are required in the fraction of inspired oxygen or the level of positive end-expiratory pressure. 8

Spontaneous Breathing Trials Outcomes 1.5 day reduction duration mechanical ventilation –25% relative risk reduction 1.0 day reduction ICU length of stay –Not statistically significant Reductions total ICU costs Reductions in complications including reintubation Ely et al. NEJM 1996; 335:

Treatment protocol Girard et al. Lancet 2008; 371: 126–34 10

ABC Trial: Awakening and Breathing Controlled trial Population 336 ICU patients on mechanical ventilation Four tertiary-care hospitals Intervention (RCT) Control group: sedation per usual plus daily SBT (n=168) Rx group: daily SAT followed by SBT (n=168) All patients received an infusion of morphine for analgesia. Girard et al. Lancet 2008; 371: 126–34 11

ABC Trial: Awakening and Breathing Controlled trial 3.1 increased days without mechanical ventilation –21% relative risk increase 3.8 day reduction ICU length of stay –29% relative risk reduction 4.3 day reduction hospital length of stay –22% relative risk reduction Number needed to treat (NNT) = 7.4 for one life saved Girard et al. Lancet 2008; 371: 126–34 12

Practical SAT The SAT consists of two parts, – a safety screen and – the trial. The safety screen attempts to assure the trials will not be used when contraindicated. Patients pass the screen unless: 13

The Safety Screen Sedation for active seizures or alcohol withdrawal Already receiving escalating doses of sedative for agitation Receiving neuromuscular blockers Active myocardial ischemia in prior 24 hours Evidence of increased ICP 14

If patient passes the safety screen  Awakening Trial All sedatives and analgesics used for sedation are stopped. Analgesics used for pain are continued. A patient passes the SAT if awake and can do 3 of 4 simple tasks on request: open eyes, look at caregiver, squeeze hand or stick out their tongue. OR 15

If patient passes the safety screen can go ≥ 4 hrs w/o –sustained anxiety –Agitation or pain –RR of 35 for >= 5 minutes –SpO 2 =5 minutes –an acute cardiac dysrhythmia –≥ 2 signs of respiratory distress Tachycardia, bradycardia, use of accessory muscles, abdominal paradox, diaphoresis, obvious distress 16

SAT Failure If a patient fails the SAT, sedatives are restarted at one half the prior dosage and titrated up as needed. 17

SAT Success? Maintain adequate oxygenation (SpO 2 >=88% on an F 1 O 2 of ≤50% and a PEEP ≤8 cm H 2 O) any spontaneous inspiratory effort in a 5-min period no agitation no significant use of pressors or inotropes no evidence of increased ICP 18

SAT success  SBT Patient breathes through either a T-tube circuit of a ventilatory circuit with CPAP of 5cm H 2 O or pressure support ventilation of less than 7cm H 2 O. Typically FIO2 is ≤50% and PEEP≤8 19

SBT success? Patients pass the trial if they don’t develop any of the same criteria as for the SAT for 120m If they pass, the prescriber is notified for extubation order. 20