A comparative analysis of USG-Guided pain management approaches for sternotomy in cardiac surgeries: Transverse Thoracic Muscle Plane Block versus Pecto-Intercostal Fascial Block

Aims-To study and compare effect of USG guided transverse thoracic muscle plane block with pecto-intercostal fascial block for post-sternotomy pain in cardiac surgery.

OBJECTIVES-:

ï‚· To find Opioid consumption in first 24 hours after sternotomy in cardiac surgery.

ï‚· To access Pain score in numeric rating scale(NRS) in 12 hr. and 24 hr.

Introduction

Pain management has a critical role in providing an earlier return to normal activities.1 Currently, opioid-based analgesia strategies have the main role after cardiac surgery, but respiratory depression nausea, vomiting, itching, urinary retention, and risk of opioid addiction are well-known undesirable effects. Pain can cause pulmonary complications such as insufficient clearance of secretions, prolonged weaning, acute respiratory failure as a result of shallow breathing, and ineffective coughing. Effective control of pain is essential for the reduction of all these complications, including postoperative mortality and morbidity.2,3 Cardiac surgery is mostly done via open midline sternotomy. The bone cutting incision is major cause of morbidity. Most sternotomy pain occurs because of tissue injury in the skin, subcutaneous tissues, bone, and cartilage. Intercostal nerves arising from thoracic nerve roots innervate the sternum, ribs, and surrounding subcutaneous tissue. The principal thoracic nerves supplying the sternum are T2 to T6 4,5 The effectiveness of thoracic epidural and paravertebral blocks have been demonstrated following cardiac surgeries. However, many anesthesiologists are reluctant to utilize these blocks due to the possibility of developing a spinal hematoma from heparinization and hemodilution.6 In recent years, the popularity of fascial plane blocks accompanied by ultrasound has increased in the management of postoperative analgesia. With ultrasound increasing anatomic control, it encourages anesthesiologists to use regional anesthesia. Fascial plane8 blocks, in which the risk of bleeding is low compared with central neuraxial techniques or deep nerve blocks, are increasingly becoming a part of multimodal analgesia as an alternative pain management strategy in cardiac surgery. Parasternal blocks,7 erector spinae plane (ESP) blocks,8 and pectoralis nerve blocks9 have been successfully used to alleviate sternotomy pain after cardiac surgery. Transversus thoracic muscle plane block (TTMPB) was first described by Ueshima et al.10 in 2015. They showed in a cadaver study that the local anesthetic placed between the intercostal muscles and the transverse thoracic muscle covers T2-T6 intercostal nerves.11 Data other than a pilot study evaluating the effect of the TTMPB on sternotomy pain12 are in the form of case reports. To the authors’ knowledge, this study is the first randomized, controlled, double-blind study about the effectiveness of TTMPB in cardiac surgery. The PIFB consists in injecting local anesthetics close to the sternum in the plane between the pectoralis major and internal intercostal muscle

TTMPB and PIFB have similar effectiveness in acute post-sternotomy pain treatment. Since PIFB is easy to apply and has a low rate of serious complications. PIFB may be a more attractive option for acute post-sternotomy pain management.

The current study was designed based on the hypothesis that the perioperative analgesic effectiveness of TTPB and PIFB in children undergoing cardiac surgery via median sternotomy is comparable.

SOURCE OF DATA - This study will be carried out at the Department of Anaesthesiology and Critical Care, Sri Aurobindo Institute Of Medical Sciences Hospital, Indore (M.P).

SELECTION OF CASES- After Ethical committee clearance, a total of 59 patients age 18-70years scheduled for elective cardiac surgeries will be selected randomly. An informed written consent will be taken from all the patients relatives in groups after the approval of institutional ethical committee and as per inclusion and exclusion criteria

METHOD OF COLLECTION OF DATA –

•118 Patients posted for elective cardiac surgery will be selected for the study. All patients will undergo thorough pre-anaesthetic evaluation before surgery.

•Routine investigations will be done.

•Written informed consent will be obtained.

•Patients will be advised Nil Orally for a period of 6-8 hours prior to surgery.

After the clearance from ethical committee, Patients will be enrolled for the study and after informed consent after explaining the procedure and intervention specific to study will be taken.

Patients will be divided into two groups:

1. GROUP TTP – Transverse Thoracic Muscle Plane Block

2. GROUP PIF – Pecto-Intercostal Fascial Block

In group TTP 20ml of 0.25% ropivacaine will be injected bilaterally under ultrasound guidance in tranverse thoracic plane while in group PIF, 20ml of 0.25% ropivacaine will be injected in pecto-intercostal plane under ultrasound guidance .

In post operative protocol time of extubation will be looked for.

Statistical Analysis Plan

The data will be collected and entered in MS excel 2010. Data will be analyzed from R software and will be presented in frequency table.

Descriptive statistics will be calculated as mean & SD for quantitative variable and frequency and percentage for qualitative or categorical variables. Pie or bar diagram will be used for Qualitative or demographical variables. Independent t test/Mann Whitney U test will be applied for compare between two quantitative groups. Repeated measured

ANOVA test/Friedman test will be applied for more than 2 time follow

up and post hoc test will be applied for multiple pre and post comparisons

If p value <0.05, considered as statistically significant result and if p-value>0.05, then it is statistically insignificant result