The Effect of Brachial Plexus Block on Diaphragm Movement

A Randomized Controlled Study on the Effect of Brachial Plexus Block with Different Concentrations of Ropivacaine on Diaphragm Movement

The purpose of this study is to quickly evaluate the degree of phrenic nerve block by observing the changes of diaphragm movement through ultrasound, and to find the best scheme for clinical application by controlling the concentration of narcotic drugs, so as to reduce respiratory related complications.

40 ASA grade I - II patients were selected from the patients who underwent shoulder ligament rupture repair surgery under selective general anesthesia combined with brachial plexus block analgesia in the sports medical center of our hospital. They were randomly divided into two groups: high concentration group (group I) and low concentration group (Group II), with 20 cases in each group. 40 patients underwent a single brachial plexus block under ultrasound guidance before general anesthesia. In group I, ropivacaine 100mg + normal saline to 20ml (0.5% ropivacaine 20ml), and in group II, ropivacaine 40mg + normal saline to 20ml (0.2% ropivacaine 20ml). The high-frequency ultrasonic probe was located in the intermuscular sulcus, clearly exposing the three trunks of the brachial plexus. Using out of plane technology, the drug solution was injected around the brachial plexus, Ultrasonic images showed that the drug solution evenly wrapped the nerve trunks. The diaphragmatic movement of patients was scanned and recorded before and 30 minutes after block. The dispensing nurse, the operator and the follow-up doctor are independent individuals, and the operator and the follow-up doctor do not know the patient grouping. After confirming the effect of nerve block, the operating doctor will carry out general anesthesia and start the operation. The patients were followed up 6 hours after operation, and NRS scores were made and recorded.

Inclusion Criteria:

• operation type: patients undergoing shoulder ligament rupture repair under selective general anesthesia combined with nerve block analgesia
• age: 18 ~ 65
• ASA class I or II

Exclusion Criteria:

• patient rejection
• brachial plexus injury
• severe cardiovascular disease
• allergic to the drugs used in the test
• infection at the puncture site
• difficulty in understanding (unable to understand the pain assessment method)
• recent history of opioid use