Objective: This systematic review evaluates the clinical effectiveness of the spontaneous awakening trial (SAT)–spontaneous breathing trial (SBT) protocol in mechanically ventilated sedated patients (MVSPs) within intensive care units (ICUs). Methods: A comprehensive search identified 18 studies involving 12 284 patients from 11 countries. Outcomes included weaning success, mechanical ventilation (MV) duration, sedation time, complications, cognitive impairment, ICU stay length, and mortality. Results: Implementing the ABCDE bundle, particularly the paired SAT-SBT protocol, significantly reduced ventilation and sedation time by nearly 50%. The intervention was associated with decreased medication use, improved patient wakefulness, and higher extubation success rates. The intervention group showed shorter durations of MV, ICU, and hospital stays. Cognitive impairment was less frequent in the intervention group at the 3-month follow-up. Nurse workload was unaffected, and 1-year mortality was lower in the SAT-SBT group. Conclusion: The systematic review supports the clinical effectiveness of the paired SAT-SBT protocol within the ABCDE bundle for MVSPs in ICUs. The protocol improved weaning outcomes, reduced ventilation and sedation time, decreased complications, and shortened durations of MV and ICU stay. The findings underscore the benefits of a comprehensive approach integrating SAT and SBT in managing MVSPs. Further research is needed to optimize intervention timing, address implementation challenges, assess cost-effectiveness, and determine generalizability across diverse patient populations and healthcare settings.