Application Of Ultrasound Localization For Combined Spinal-epidural Anesthesia In Obstetric Surgery

Objective Combined spinal-epidural anesthesia(commonly known as "CSEA")is the most commonly used in cesarean section.Traditional intraspinal anesthesia is not supported by visualization techniques.Positioning puncture gaps can only be performed by touching the bone markers of the body surface.The puncture success rate is often limited by the operator's clinical experience.Even experienced anesthesiologists often cause the puncture too deep or too shallow,leading to puncture failure and even serious complications.Therefore,precise puncture and depth of penetration are especially important for patients.Ultrasound technology has brought us from darkness to light,and has made a breakthrough in anesthesia.It can visually observe changes in spinal bones?maternal muscle and other soft tissues then reflect the impact of these changes to us.Therefore,in obstetric anesthesia,ultrasound has been widely used.For intraspinal anesthesia,both epidural anesthesia and subarachnoid anesthesia are associated with the endorachis and arachnoid membrane,and the occurrence of related complications is closely related.However,few people can accurately predict the depth of this membrane to guide anesthesia puncture,and research reports in obstetric patients are even rarer.In this study,ultrasound was used to directly predict arachnoid depth in the ultrasound-located group(U)to guide intraspinal anesthesia puncture.To explore the feasibility of ultrasound to predict the depth of arachnoid for patients undergoing cesarean section under epidural or spinal anesthesia,and to explore the clinical value of ultrasound-located combined spinal and epidural anesthesia for patients undergoing cesarean section.Methods One hundred patients with ASA I-II were divided into two groups,using random number table method,who were undergoing elective cesarean section.the ultrasound localization group(U)and the traditional manipulation group(T).Patients with history of spinal surgery,central nervous system disease,and contraindications for intrathecal anesthesia were excluded.For patients who meet the criteria,in the ultrasound localization group(U),ultrasound was used to position the puncture point before the anesthesia,and the depth of the patient's L2-3 gap skin to the arachnoid was measured and recorded as Ultrasonic measurement depth(UD).Then,the midway approach anesthesia puncture was performed,and the depth of the epidural needle depth(ED),the spinal needle depth(SD),and the depth of skin to the endorachis and arachnoid membrane(AD)were measured.Then Pearson linear correlation and single factor linear regression analysis were used to compare the correlation between UD and AD,UD and ED,UD and SD,and the consistency of the two was tested by Bland-Altman analysis.The differences between the one-time puncture success rate,the number of punctures,and the incidence of puncture complications were compared between the ultrasound-targeted group(U)and the conventional manipulative group(T).Results A total of 100 patients participated in the study,and 8 of them were excluded for trial.One-way analysis of variance showed that UD showed significant difference in AD,ED and SD,and the difference was statistically significant(P<0.05).Pearson correlation analysis showed that UD had significant correlation with AD,ED and SD,UD The Pearson correlation coefficient with both UD and AD was r=0.966(95% CI: 0.9177~1.0168,P<0.05).The linear regression equation was AD=1.0681*UD-0.3165(R2=0.966,R=0.933,P<0.05);the 95% consistency limit was-0.3689~0.3715 cm.The Pearson correlation coefficient of both UD and ED was r=0.970(95% CI: 0.9215~1.0263,P<0.05).The linear regression equation is ED=1.0371*UD-0.3434(R2=0.9399,R=0.970,P<0.05).The 95% consistency limit is-0.5042~0.1634 cm;Through Pearson correlation analysis,we obtained the Pearson correlation coefficient r=0.957 of UD and SD and the 95% CI of correlation coefficientr: 0.9091~1.0073,P<0.05.The results show that UD is significantly correlated with SD.The linear regression equations of UD and SD were also obtained as SD=1.0755*UD-0.1727(R2=0.9154,R=0.957,P<0.05),and the 95% consistency limit was-0.2437~0.6028 cm.Compared with the traditional manipulation group(T),the number of punctures in the ultrasound positioning group(U)was significantly less than the traditional manipulation group(T)(p<0.05),and the success rate of one puncture was significantly higher than that of the traditional manipulation group(T)(p<0.05),at the same time,we get that the maternal complications were significantly less in the ultrasound-targeted group(U)than in the conventional manipulation group(T)(p<0.05).Conclusion Ultrasound measurement of skin to arachnoid depth UD has a significant correlation with actual epidural puncture depth ED and spinal anesthesia depth SD and actual endorachis and arachnoid membrane depth AD.Ultrasound can be used for epidural anesthesia and spinal anesthesia depth prediction.The clinical safety of epidural anesthesia or spinal anesthesia is further improved,and has high clinical application value.Epidural anesthesia and spinal anesthesia under ultrasound localization can significantly improve the success rate of puncture and reduce the incidence of maternal anesthesia puncture complications.