Objective to describe a strategy of mediated training by bedside supervised practice for nurses during the COVID-19 pandemic and to determine nurses’ perception about contribution of bedside training for the acquisition of knowledge and skills for healthcare practice in critical care settings. Methods this was an observational, longitudinal, retrospective and descriptive study that used a quantitative approach, conducted at a large private health care facility in the city of São Paulo, Brazil. The data collected refer to the period from April to June 2021. The research was approved by the Research Ethics Committee of Hospital Israelita Albert Einstein, under Protocol 5.423.393. Ten procedures were selected for supervision, such as tracheal aspiration, nasogastric tube, venipuncture, donning, dressing and equipment handling. Data obtained were analyzed using descriptive analyses and statistical tests. Results of the participants (72), 87.7% were women with mean age of 33 years and their mean work experience was 9 months (50%). Initially, professionals participated in the standard 26-hour institutional training and, later, in supervised practice-mediated training. The mean time per procedure was 45 minutes. The median proficiency in eight of the procedures was eight. Most professionals rated themselves as confident (98.9%) and satisfied with the training (99.4%). Conclusion and implications for practice the training enabled a structured process of identification and monitoring of care practice, allowing for an effective strategy to provide prepared professionals who work safely.