Observational study for laryngeal mask anesthesia combined with nerve block in internal fixation for rib fractures

Abstract

Background: General anesthesia with endotracheal intubation always has been considered mandatory for rib fractures surgery. Recently, there has been interestng in nonintubated technique of LMA anesthesia for lung surgery. We developed a protocol with laryngeal mask(LMA) anesthesia combined with nerve block for rib fractures surgery, and performed it in several cases prospectively. Methods: Twenty patients undergoing unilateral rib fractures surgery were enrolled. Thoracic paravertebral block(TPB) and/or erector spinae plane block(ESPB) were carried out before LMA anesthesia. The vital signs(HR, BP, SpO 2 ) and parameters of breath were gathered during the operation. The arterial blood gas analysis and chest film were performed preoperatively and on the next day after operation. All patients received postoperative continous analgesia pump contained with 500mg of tramadol and 16mg of lornoxicam after the operation, and intravenous 50mg flurbiprofen Bisindie in the ward. Postoperative nausea and vomiting(PONV) within 48 hours after surgery and NRS pain scoreat 6(T1), 12(T2), 24(T3) hours after surgery were assessed as well. We also recorded the incidence of perioperative reflux, aspiration and nerve block complications. Results: Thirteen males and seven females(mean age 54 years) were enrolled in this trial. 6(30%) had a flail chest, 9(45%) had haemothorax, 2(10%) had pulmonary contusion. The vital signs and spontaneous breathing were kept stable. End-tidal carbon dioxide concentrations(EtCO 2 ) were in an acceptable range(no more than 63 mmHg in all cases). The mean value of postoperative PaO 2 was increased than that of preoperative PaO 2 (91.2±16.0 vs. 83.7±15.9 mmHg, P=0.004). The mean value of preoperative and postoperative PaCO 2 was(42.1±3.7 vs. 43.2±3.7mmHg, P=0.165) respectively. Postoperative NRS at T1, T2, T3 was (3±1, 2±2, 0) respectively. No one suffered from PONV. In addition, perioperative reflux, aspiration and nerve block complications didn't appear in all cases. Conclusions: The technique of laryngeal mask anesthesia combined with nerve block was feasible in the internal fixation for rib fractures.