Rhomboid intercostal plane block (RIB) has been described in the last decade. Various clinical applications have been found to provide hemithorax analgesia. The use of cardiac implantable electronic devices (CIEDs) is increasing due to comorbidities in the elderly population. Increased myocardial stress with pain in these patients may increase the frequency of adverse cardiac events. Therefore, perioperative pain management ensures patient welfare, reduces complications, and maintains stable hemodynamic values. In this study, we aimed to evaluate the outcomes of RIB in terms of perioperative analgesia and patient and physician satisfaction in patients undergoing CIED.

In accordance with the study design, a randomization list for the two groups is generated by an independent individual using a computer-assisted program (www.randomizer.org). Equal numbers of participants are assigned to either the intervention or control group in a 1:1 ratio. Patients included in the study will be randomized into two groups of 25 patients each. One group (local anaesthesia group - LAG) will receive only local anaesthesia (prilocaine 2%) as per the standard procedure of the institution. The other group (RIB group - RIBG) will receive RIB in addition to the standard procedure. Demographic and clinical data regarding the patients and the procedures performed will be recorded. Information about the first and second rescue treatments in cases of pain during the procedure, as well as the first and second rescue treatments during postoperative follow-up, will also be documented in the same database. Pain levels during the procedure, at the end of the procedure, and at 3, 6, 12, and 24 hours postoperatively will be assessed using the NRS-11. Patient and physician satisfaction will be evaluated using a five-point Likert scale. This study aims to evaluate the efficacy of RIB in patients undergoing CIED implantation by performing pain assessments with the Numeric Rating Scale-11 (NRS-11) during the procedure and the postoperative period. As a secondary outcome, patient and physician satisfaction levels will be assessed during the procedure.

Inclusion Criteria:

• over 18 years of age,
• no previous ICD or Pacemaker implantation attempt
• ASA ( American Society of Anesthesiologists ) score of 2-3,
• INR < 2.0 ,
• Signing the volunteer consent form,
• Patients who met the study criteria will be included in the study.

Exclusion Criteria:

• Morbidly obese patients (BMI>35 kg/m2),
• Advanced decompensated heart failure with New York Heart Association (NYHA) stage 4,
• Having severe chronic obstructive pulmonary disease,
• Allergy to the prescribed medications ,
• Those who have a skin infection or lesion in the area to be blocked,
• Cannot be communicated and cannot be given a position,
• Severe psychosis and progressive neurological deficits and muscle disease,
• ICD/ Pacemaker revision or upgrade to be made,
• ICD battery replacement
• Pregnant patients will be excluded from the study.

The RIB procedure for the intervention group will be performed in a separate room 60 minutes prior to the patient's transfer to the cardiac electrophysiology laboratory, as described in the methodology section. When the patient arrives at the electrophysiology lab, the cardiologist performing the CIED implantation is not informed whether RIB has been administered beforehand. However, due to the nature of the study, patients are not blinded to the treatment.