BACKGROUND Postoperative pain after cardiac surgery is a very important issue and affects recovery, risk of postoperative complications and quality of life. The pain management has been traditionally based on intravenous opioids with growing evidence suggesting the use of opioid-free and opioid-sparing techniques to reduce its adverse effects. CASE PRESENTATION We report the case of a 75-years-old frail patient underwent awake mediastinal revision with subxiphoid access due to deep sternal wound infection using a Pectoralis-Intercostal Rectus Sheath (PIRS) plane block. During the procedure the patient never reported pain receiving acetaminophen 1 g every 8 hours for postoperative pain management without others pain relievers. CONCLUSION Ultrasound guided PIRS block could be an effective and safe analgesic technique to manage sternal and subxiphoid drainage pain in patients undergoing cardiac surgery via subxiphoid approach.