The feasibility of pressure pain tolerance threshold to assist in the selection of anesthesia for transperineal prostate biopsy
Objective To explore the feasibility of pressure tolerance threshold(PTO)in evaluating the effect of local anesthesia in patients undergoing transperineal prostate biopsy.Methods Patients who underwent periprostatic nerve block prostate biopsy in Northern Jiangsu People's Hospital from March 2022 to October 2023 were prospectively enrolled.Inclusion criteria:① suspicious prostate nodules detected by digital rectal examination,any prostate-specific antigen(PSA)value;②transrectal prostate ultrasound(TRUS)or magnetic resonance imaging(MRI)showing suspicious lesions,any PSA;③ the PSA>10 ng/ml;④PSA 4-10 ng/ml,suspicious free/total PSA or suspicious PSA density.Inclusion was required if one of these criteria was met.Exclusion criteria:① previous history of prostate biopsy or prostate surgery;② severe cardiovascular and cerebrovascular diseases or coagulation disorders;③ severe urinary tract infection;④ taking analgesics within 24 hours before surgery;⑤ unable to complete the pain score or refused to cooperate;⑥ rectal stenosis or other rectal lesions detected by digital rectal examination.The PTO of all patients was measured by the same physician using a tenderness measuring instrument before puncture.Visual analogue scale(VAS)was used to evaluate the pain during the operation.According to the VAS score,the patients were divided into mild pain group(VAS score 0-3 points)and moderate to severe pain group(VAS score 4-10 points).The clinical data of the two groups were compared.The correlation between PTO and VAS score was further analyzed.The receiver operating characteristic(ROC)curve of PTO to predict pain during puncture was drawn,and the optimal cut-off value of PTO was calculated by the maximum Youden index.Results A total of 304 patients were enrolled in this study,including 184 patients in the mild pain group and 120 patients in the moderate to severe pain group.There were no significant differences in age[69(63,73)years old vs.69(61,74)years old],body mass index[24.0(22.9,25.0)kg/m2 vs.23.9(22.8,24.7)kg/m2],PSA[14.6(10.5,25.1)ng/ml vs.14.0(10.5,20.7)ng/ml],and hypertension[59.8%(110/184)vs.64.2%(77/120)]between the mild pain group and the moderate to severe pain group(P>0.05),while there were significant differences in PTO[(6.69±1.20)kgf/cm2 vs.(5.13±0.92)kgf/cm2],number of puncture needles[19(18,22)needles vs.22(20,24)needles],prostate volume[36.5(26.6,52.5)ml vs.63.2(47.4,89.4)ml],diabetes[35.3%(65/184)vs.23.3%(28/120)],and major trauma experience[37.5%(69/184)vs.15.8%(19/120)](P<0.05).There was a high correlation between PTO and VAS score(r=0.689,P<0.001).ROC curve analysis showed that when PTO was 5.99 kgf/cm2,the accuracy of predicting moderate to severe pain during prostate biopsy was the highest.The AUC was 0.848,the Youden index was 0.675,the sensitivity and specificity were 89.2%and 78.3%,respectively.Conclusions PTO can evaluate the effect of local anesthesia in patients undergoing transperineal prostate biopsy.PTO can be measured before surgery in patients undergoing transperineal prostate biopsy.When the patient's PTO is ≥5.99 kgf/cm2,the patient's pain tolerance is better and the local anesthesia effect is feasible.When the patient's PTO is less than 5.99 kgf/cm2,the patient's pain tolerance is poor,so the patient could be recommended to undergo spinal anesthesia or general anesthesia to reduce the pain during prostate biopsy.