Background: The aim was to evaluate safety aspects of patient-controlled sedation and analgesia (PCS) for extracor-poreal shockwave lithotripsy (ESWL) and PCS to be handled by non-anaesthesiology doctors. Methods: Thirty-four ASA I-III patients used PCS with propofol and alfentanil for ESWL in this interventional study. Strict safety limits were defined regarding respiratory rate (RR), heart rate (HR), mean arterial blood pressure (MAP), oxygen saturation from pulse oximetry (SpO2), and transcutaneous partial pressures of oxygen (PtcO2) and carbon dioxide (PtcCO2). The pa-tients’ levels of consciousness was graded on a five-point scale and monitored with Bispectral Index (BIS). A nurse anaesthetist was supervising the procedure but was instructed to intervene only if safety limits were breached. No sup-plementary oxygen was given. Results: All patients responded to verbal stimuli during treatment. Cardiovascular sta-bility was maintained, but respiratory variables were affected. Two patients with SpO2 < 90% and two cases of RR ≤ 8 were diagnosed, and seven patients became hypercarbic (PtcCO2 ≥ 6.5 kPa). In 18 patients hypoxaemia was indicated as PtcO2 ≤ 8.0 kPa. All these 18 patients were given supplementary oxygen. There was no correlation between dose of drugs, age, weight or any vital variable. The 34 patients would use PCS again in the case of future treatment. Conclu-sions: During ESWL treatment PCS can be used with good patients’ satisfaction, and maintained cardiovascular stabil-ity, but PCS had an indisputable effect on pulmonary function with hypoxemia (resulting in need for supplementary oxygen) or hypercarbia. The person in charge of PCS must therefore be trained to perform according to the guidelines for sedation and/or analgesia by non-anaesthesiology doctors.