Observation Of Ultrasound-guided Intercostal Nerve Block For Breast Lump Resection

Objective:Intercostal nerve block was commonly used nerve block in thoracic and abdominal surgery anesthesia, analgesia and pain management. The accurate positioning of the puncture site was very importent to the successful block.The traditional blind puncture mainly rely on anatomical landmarks. With the introduction of ultrasound technology, the technology for ultrasound-guided intercostal nerve block was gradually extended.We hoped to find a new method for positioning of ultrasound-guided intercostal nerve block,and to evaluate the oneset time, anesthetic effect and complications for ultrasoundguided intercostal nerve block compaired to the blind method.Methods:Part one: Reading CT images of 45 patients randomly and retrospectively.We recorded the patients’ gender, age, weight and height.All the patients were divided into two groups according to the gender.Point A was the intersection of the first rib and the midaxillary line. Point B was the intersection of the superior thoracic artery and the midaxillary line. Measured the distance between the horizontal planes for point A and B. We recorded the value for AB as positive when the point B above the first rib,and negative when below.Recording the width of the first rib(W1) and first intercostal space(W2) in the midaxillary line in 45 patients using ultrasound. Recording the distance from the skin to the pleural in the third intercostal space(D3), the fourth intercostal space(D4) and the fifth intercostal space(D5).Part two: Sixty patients undergoing elective single breast lumpectomy,and the breast lumps range located in T3-5,between the anterior axillary line and the parasternal line were randomly divided into ultrasound-guided group(group U) and blind method group(group B)(n=30). We recorded the patients’ age, weight and height.Group U used ultrasound- guided intercostal nerve block out-of-plane technique,while group B completed intercostal nerve block without ultrasound technology. Local anaesthetic mixture was prepared by adding 10 milliliters 1% ropivacaine to 10 milliliters 2% lidocaine to obtain a total 20 ml solution.All the sixty patients received the anaesthetic mixture 3 ml for each intercostal space. In patients operating chest wall side draw three lines that the anterior axillary line(x-line), the mid-clavicular line(y-line) and the line between the mid-clavicular a and the nterior midline line(z-line).Three lines and there ribs were named the intersections T3 x, T3 y, T3 z, T4 x, T4 y, T4 z, T5 x, T5 y, T5 z.Tested the nine intersections’ blockade effect using a 16 G needle piont every minute,kept the effect into 0 and 1:0,no pain relieved or slightly hypalgesia;1, completely painless. Observed the block onset time(to complete the block T5 x hypoalgesia time), perfect time(no better pain relieved time) and Visual Analogue Scores at the beginning and the ending of the surgery. Recorded changes in vital signs in the operation room. Local anesthetic(0.5% lidocaine) was infiltrated additionally by the surgeon intraoperative if the patient felt pain or discomfort. Recorded the amount of patients required additional local anesthetic.Recorded the puncture discomfort and the complications.Results:Part one: Two patients’ point B cound not be found in the CT images.There were no correlations between AB value and the height, weight,BMI of all the patients(P>0.05). There were correlations between W1, W2, D3, D4, D5 and height,weight and BMI of all the patients(P <0.05). AB(1.51±5.73mm) is far less than W1(1.48±0.26cm) and W2(1.78±0.16cm).Superior thoracic artery close to the first rib.Part two: All the patients were successfully completed the breast lumpectomy surgery. No significant HR and MAP fluctuations in both groups of patients(P>0.05). Onset time and perfect time in group U were faster than group B(P<0.05). Group U had lower Visual Analogue Scores than group B(P<0.05) at the beginning and the ending of the surgery. The amount of additional local anesthetic for group U was significantly less than group B(P<0.05). 8 patients in group U complained of puncture discomfort while 4 in group B(P>0.05). 2 patients in group U complained of dizziness after block while 1 in group B(P>0.05).Group B had one case of pneumothorax,but none in group U(P>0.05).Conclusion:Superior thoracic artery can guide the positioning of the first rib for ultrasound-guided intercostal nerve block. The distances from the skin to the pleural in the third intercostal space, the fourth intercostal space and the fifth intercostal space can guide the puncture depth of the blind intercostal nerve block.Ultrasound-guided intercostal nerve block has the faster onset and perfect time,better intraoperative and postoperative Visual Analogue Scores and less additional local anesthetic than the blind mothod. Considering more secure,effective and reliable.