Compare Of Preprocedure Ultrasound Scan And Real Time Ultrasound Guidance For Combined Spinal-epidurat Anesthesia In Pregnant Women With Poor Surface Landmarks

BackgroundCombined spinal-epidural anesthesia(CSEA)has a rapid onset and highly reliable regional blockade.The CSEA technique is in widespread use,particularly for major orthopaedic surgery and in obstetrics.The quality of CSEA is heavily depends on accurate identification of the spinal space.Tranditional landmark-guided techniques for epidural needle placement are based on palpation of anatomical landmarks,which can be difficult with some subjects.Anatomical landmarks are useful but are surrogate markers,difficult to palpate in the obese and those with oedema in the back,do not take into account anatomical variations or abnormalities,and frequently lead to incorrect identification of a given lumbar interspace.This may lead to multiple attempts,pain and discomfort to the patient,a failed block,complications,frustration for the anesthesiologist,and poor patient satisfaction.In recent years,ultrasound has been presented as an innovative and promising device to facilitate neuroaxial anesthesia application and it is stated that significant information can be obtained pertaining to spinal anatomy through the use of ultrasound.However,there are limited reports of lumbar neuraxial blocks using ultrasound(US)in patients with poorly palpable surface landmarks.ObjectiveThe aim of this study was to compare the effects of pre-procedure US versus real-time US guidance in pregnant women with poorly palpable surface landmarks.MethodsThe study was conducted prospective-randomly after receiving approval from the ethics committee and the patients' permission.Inclusion criteria were:pregnant women with poorly palpable surface landmarks;aged 18-48 years old;planned cesarean section to terminate the pregnancy;ASA ?-?.Exclusion criteria were:pregnant women to be younger than 18 or older than 48;emergency cases;patients with spinal anesthesia contraindications;patient refused.41 patients were randomly assigned in a 1:1 ratio to one of two groups:the P group(n=21)which underwent a pre-procedure spinal US to determine the optimal lumbar level for injection or the R group(n=20)which underwent both a pre-puncture US and real-time ultrasound-guidance for needle insertion.The skin-dura mater distance,skin-spinous process distance and epidural needle depth were measured.The number of puncture site,number of redirections and procedure time were recorded.The degree of visibility of the vertebral space was observed through ultrasound and was numerically scored.The patient satisfaction,procedural difficulty scores,procedure immediate complications and procedure complications after 12h,48h and 7d were also recorded.ResultsOne subject did not participate in the study because the CSEA in L3-4 failed.There was no difference between the skin-dura mater distance,skin-spinous process distance,epidural needle depth,ultrasound visibility score and patient satisfaction in the two groups.In the R group,the reduction in the number of puncture site and attempts was significant(P<0.05).Anesthesiologists rated the R group procedure more difficult than the P group(P<0.005).Compared with P group,extra time was needed to prepare the transducer in R group.ConclusionThis study shows that both pre-procedure US and real-time US guidance are feasible for performing CSEA in pregnant women with poorly palpable surface landmarks.The study also suggests that real-time US guidance for CSEA in these patients in comparison to the pre-procedure US technique was completed in longer time,with lower insertion attempts,and higher procedural difficulty scores.