Critical Care Unit (CCU) patients are exposed to the risk of the so-called “Critical Care Unit Triad” of agitation, pain, and delirium. Critically ill patients are often sedated for a comfortable stay, to comply with mechanical ventilation or to therapeutically reduce intracranial metabolism and hypertension. However, critically ill patients are often over- or under-sedated that might result in adverse complications and poor outcomes. Depth of sedation is assessed via numerous indices like Sedation Agitation Scale (SAS), Richmond Agitation-Sedation Scale (RASS), Observer’s Assessment of Alertness/Sedation (OAA/S) Scale, or Ramsay Score. These scores have serious limitations like inconsistency, intermittent assessments, frequent patients’ stimulations, and depending on patients’ behavior and response. Thus, several processed Electroencephalography-Depth Of Anesthesia (pEEG-DOA) monitors have been suggested as possible objective alternatives to provide real-time, continuous bedside clinical sedation assessment tools. One possible useful application of pEEG-DOA could be monitoring of physiologic sleep in critical care patients who almost uniformly suffer from sleep deprivation and sleep disruption as they lose their circadian rhythm in a CCU harsh frightening noisy environment with frequent nurse-patient interactions, altered sleep manner manifesting as fragmented sleep, extended light sleep, frequent arousals with fewer slow electroencephalography (EEG) waves and Rapid Eye Movement (REM) sleep, cardiovascular changes such as hypertension, increased sympathetic activity, decreased cognitive function like delirium, memory deficiency, slow reaction time, and decline in quality-of-life parameters. The Italian Society for Anaesthesia, Analgesia, and Intensive Care (ISAAIC) advocates that using objective tools such as Bispectral Index, once validated for physiological sleep monitoring in CCU patients, could significantly improve patients’ morbidity and outcomes via increasing their sleeping time.