Delirium is one of the postsurgical complications in the geriatric population. Its incidence was reported up to 65% following major operations, and it is accompanied with high cost, morbidity and mortality. A 65-year-old man candidate for laparoscopic cholecystectomy under spinal anesthesia. His hypertension was under control with captopril 50 mg daily. In the middle of the surgery, he had cardiac arrest and cardiopulmonary resuscitation was performed. Vital signs improved within 6 minutes, but he was unconscious after operation. Patient was transferred to ICU and was treated for metabolic changes, hemodynamic instability and midazolam or haloperidol for agitation and restlessness symptoms. Blood tests, ECG, brain scan, and MRI were reported normal. Patient had impaired consciousness for 8-9 days, and he was discharged from the hospital in good physical status and totally conscious state on day 12. Patient suffered chest pain and died 4 days later. Postoperative delirium can be predicted in this patient considering all risk factors; male gender, advanced age, cardiac arrest, hemodynamic disorder, and admission in ICU are some of the predisposing risk factors. Treatments included removing intensifying stressors, treating risk factors, limited use of tranquilizers, pain control and finally using antipsychotics like haloperidol for aggressive behaviors.