4. Discussion
obesity, obese, cord injury
OBESITY, OBESE, SECONDARY, BLIND, COMPLICATIONS
This study indicated that for obese patients with CSEA, ultrasound-assisted positioning could improve the success rate of first puncture attempt and location accuracy, decrease total puncture numbers, and raise a higher satisfaction compared with the traditional landmark-guided location in open hysterectomy.We chose to carry out this study in a secondary hospital in a Uyghur agglomeration area. The first reason is that due to geographical and dietary reasons, the proportion of obese patients is significantly higher in this area. The second reason is that due to the limitations of ultrasound technology, the current state of ultrasound application is unclear in secondary hospitals that still carry out a large number of CSEA. Previous studies have reported the application of ultrasound-assisted positioning in pregnant women and elderly patients who are predictably difficult to perform with CSEA, which indicate the promising application of ultrasound in CSEA.This study showed that ultrasound-assisted positioning could better improve the success rate of first attempt (78.4% vs 52.9%, Another interesting conclusion that we have drawn from this study is that overall agreement rate of ultrasound-assisted and landmark-guided L3-4 was 67%. landmark-guided L3/4 was ultrasound-assisted L2/3 in 11/51 (21.6%) and ultrasound-assisted L4/5 in 6/51 (11.8%). Here we analysis the results of the first study comparing the concordance rate of L3-4 intervertebral estimated by ultrasound-assisted and landmark-guided in obese women. This conclusion has not been particularly concerned in previous studies, but we want to be clearly aware of the exact accuracy of traditional landmark-guided positioning in obese patients with the reason that accurate positioning is the premise for the safe administration of CSEA. Ultrasound-assisted positioning is inferior than computed tomography for accurate positioning with intervertebral spaces. However, the position of ultrasound-assisted was considered as the actual intervertebral space for the purpose of saving medical costs and operation time in this study. The result is convincing to illustrate that traditional landmark-guided positioning is not reliable enough in obese patients. Thus, there may be potential risks for some obese patients with traditional landmark-guided positioning. In this study, it happened 1 case (1/51) that successful puncture position was at L1-2 in landmark-guided group. Although it had brough no spinal cord injury to the patient, and it is enough to remind of the risk in incorrect positioning. CSEA is widely used in lower extremity and abdominal surgery, and is a better alternative to anesthesia for some patients with poor cardiopulmonary function who cannot tolerate general anesthesia.Ultrasound application in CSEA is mainly divided into 2 forms, one is ultrasound-assisted with the other is real-time ultrasound-guided.In traditional landmark-guided positioning, administration of CSEA relies primarily on the palpation of anatomical landmarks. This is a blind approach to the anesthesiologist and the variability of patient anatomy may lead to discomfort and complications occurring during CSEA operation.This present study had some limitations. Firstly, it was a single-center study conducted in a secondary hospital. Secondly, the data collectors and performers were not blinded to group assignment due to the nature of this study. Thirdly, we did not perform a subgroup analysis on the obese patients, considering that the degree of obesity may be correlated with the difficulty in administration of CSEA.In conclusion, administration CSEA with ultrasound-assisted positioning can improve the success rate of first puncture attempt, reduce the total puncture-numbers, increase the accuracy of location, and raise patients’ satisfaction in obese population. Given its convenience and simplicity in operation, administration of CSEA with ultrasound-assisted positioning is suitable for obese patients in secondary hospitals.