In current prospective randomized double-blinded clinical trial, 20 patients, candidate for shoulder surgery, with grade I or II of American society of anesthesiology (ASA), will be evaluated. Patients with history of uncontrollable chronic pain and pregnancy will be excluded. Subsequent to admission in recovery ward, patients will be randomly assigned to study groups and analgesia protocol will be administered. Right after preparation of required monitoring, pain score will be determined and recorded using pain severity scoring scale. Afterward, subsequent to pain onset in patients, analgesia will be provided via routine recovery (using morphine) in control group and using incremental and low dose remifentanil in intervention group. In control group, routine recovery will provided using 0.1 mg/kg morphine administration in divided doses. In intervetion group, diluted remifentanil solution including 10 micrograms per milliliter of remifentanil will be infused 1 milliliter per 20 seconds till pain relief. Individual recording the variables will be blinded to treatment type. Variables such as pain severity, analgesia onset time, analgesia duration, patient request to receive analgesics, apnea incidence, other adverse effects (including nausea and vomiting, bradycardia, hypotension, muscle spasm, pruritus), pain recurrence time and amount of administered drugs will be recorded.