Agitation during anaesthetic emergence: An observational study of adult cardiac surgery patients in two Australian intensive care units

Background: Anaesthetic emergence agitation among adult patients being recovered after open cardiac and/or thoracic aorta surgery has not been described. Objectives: The objective of this study was to characterise emergence agitation in terms of incidence, clinical features, and consequences in a cohort of cardiac surgery patients being recovered in the intensive care unit (ICU). Methods: A prospective, observational pilot study was implemented. Over a 5-week period, the study was conducted in two metropolitan hospitals in Victoria, Australia. The cohort comprised all patients admitted to the ICUs aged >= 18 years, who had undergone cardiac surgery via an open sternotomy with general anaesthetic, and whose emergence was directly observed. Emergence agitation was defined as a Richmond Agitation and Sedation Scale score of >=+2. Results: Fifty patients were observed. Emergence agitation occurred in 24/50 (48%) of patients. Patients with emergence agitation experienced more clinical consequences than patients with calm emergence, including a significantly greater number of episodes of airway compromise (12/24, 50%, p < 0.001); ventilator dyssynchrony (23/24, 96%, p = 0.004); and hypertension (13/24, 54%, p = 0.004). Significant treatment interference (potentially dangerous patient movements such as pulling tubes) occurred with 23/24 patients (96%, p < 0.0001). Patients who underwent emergence agitation required significantly more interventions during anaesthetic emergence than patients who underwent a calm emergence. Interventions included extra nursing measures (16/24, 67%, p = 0.001) administration of sedative and/or opioid intravenous boluses (22/24, 92%, p = 0.001) and vasoactive agents (15/24, 63%, p = 0.05). Conclusions: In patients recovering from cardiac surgery in the ICU, emergence agitation was clinically important. Immediate interventions were required to prevent and manage complications.