Measuring the Quality of Pudendal Nerve Perineural Injections.

BACKGROUND: Pudendal neuropathy is a tunnel syndrome characterized by pelvic pain and may include bowel, bladder, or sexual dysfunction or a combination of these. One treatment method, pudendal nerve perineural injections (PNPIs), uses infiltration of bupivacaine and corticosteroid around the nerve to provide symptom relief. Bupivacaine also anesthetizes the skin in the receptive field of the nerve that is injected. Bupivacaine offers rapid pain relief for several hours while corticosteroid provides delayed pain control often lasting 3 to 5 weeks. Not all pudendal nerve blocks may provide complete pain relief but long-term pain control from the steroid appears to be associated with immediate response to bupivacaine. We offer a method of evaluating the quality of a pudendal block on the day it is performed using pinprick sensation evaluation. OBJECTIVE: To demonstrate that pinprick sensory changes provide a simple and rapid method of measuring response to local anesthetic and pain reduction provided by a PNPI on the day it is performed. This response defines the quality of each PNPI. STUDY DESIGN: This is a case series based on retrospective review of a private practice database that is maintained by HealthEast hospitals in Minnesota. Database information includes standard physical examination, recording techniques, and treatment processes that had been in place for several years. SETTING: Private practice in United States. METHODS: Patients with a diagnosis of pudendal neuropathy are treated with PNPIs. Two hours after each block, 2 endpoints are measured: response to a sensory pinprick examination of the pudendal territory and difference in patient-reported pain level before and after nerve block. Fifty-three men from a private practice treating only pelvic pain received the treatment in 2005. Reported pain level was not recorded for 2 patients. RESULTS: Bupivacaine in perineural injections produces varying degrees of analgesia or hypalgesia to pinprick. Normal pinprick response suggests pudendal nerves were not penetrated by bupivacaine. Patient responses varied from complete, i.e. all 6 branches anesthetized to none. Most men had 2 - 5 nerve branches anesthetized. One man had a single nerve branch that responded to bupivacaine. Three men failed to respond to local anesthetic.Changes in pre-PNPI to post-PNPI pain scores were significantly decreased (n = 51, P-value < 0.0001), indicating that bupivacaine in the PNPI reduced pain. Forty-one patients (80.4%) indicated less pain after the procedure and only 2 patients (4.0%) indicated more pain. The number of nerve branches successfully anesthetized was also significantly correlated with change in score. On average, an additional successful nerve branch anesthetized corresponded to a drop of about 0.66 in the change score (n = 51, P - value = 0.0005). CONCLUSION: PNPIs relieve pain. Anesthesia affected all 6 pudendal nerve branches in only 13.2% of patients. Complete pain relief occurred in 39.2%. This argues against use of perineural pudendal blockade as a diagnostic test. Pain relief after PNPI is associated with number of nerve branches that are anesthetized. At 2 hours after a PNPI its quality (the number of the 6 nerve branches with reduced response to pinprick from the perineural local anesthetic) is associated with subjective reduction of pain. KEY WORDS: Pudendal neuralgia, chronic perineal pain, pudendal nerve block, sensory examination, neurologic examination, pain management, chronic pelvic pain syndrome.

Does operative time affect infection rate in primary total knee arthroplasty?

BACKGROUND: Prolonged operative time may increase the risk of infection after total knee arthroplasty (TKA). Both surgeon-related and patient-related factors can contribute to increased operative times. QUESTIONS/PURPOSES: The purpose of this study was to determine (1) whether increased operative time is an independent risk factor for revision resulting from infection after TKA; (2) whether increasing body mass index (BMI) increased operative time; and (3) whether increasing experience substantially decreased operative time. METHODS: We retrospectively evaluated primary TKAs from our joint registry between March 2000 and August 2012. Cox proportional hazard models were used to assess the relationship between operative time and revision resulting from infection after accounting for age, sex, BMI, and Agency for Healthcare Research and Quality comorbidity score. Of 9973 instances of primary TKA, 73 underwent revision surgery for infection (0.73%). RESULTS: After accounting for the confounders of age and sex, operative time was not found to have a significant effect; a 15-minute increase in operative time increased the hazard of revision resulting from infection by only 15.6% (p=0.053; 95% confidence interval, 0.0%-34.0%). In addition, a five-unit increase in BMI was found to increase mean operative time by 1.9 minutes, on average, regardless of sex (p<0.0001). Operative time decreases with increasing experience but appears to plateau at approximately 300 surgeries. CONCLUSIONS: Operative time is only one of many factors that may increase infection risk and may be influenced by numerous confounders. Increasing BMI increased operative time but the effect was modest. The effect of increasing experience on operative duration of this common procedure was surprisingly limited among our surgeons. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Retreatment after percutaneous nephrolithotomy in the computed tomographic era: long-term follow-up.

OBJECTIVE: To examine the long-term retreatment rates and explore prognostic factors after percutaneous nephrolithotomy (PCNL) in the computed tomographic era. METHODS: Consecutive patients who underwent PCNL with a standardized technique attempting complete fragment detection and clearance by a single surgeon between September 2000 and June 2004 were identified. Through medical record, review details of procedures and outcomes were collected. RESULTS: A total of 166 renal units in 150 subjects were evaluated. Postoperative computed tomographic scans were conducted in 129 subjects. Median follow-up was 5.4 years (interquartile range, 4.2-6.2 years). Future ipsilateral procedures were performed in 23 renal units (14%) at a median of 2.9 years (interquartile range, 1.7-3.7 years). The cumulative retreatment rate at 7 years for noncalcium stones (24%) was not significantly higher than for calcium-based stones (14%; P = .07). Stone-free renal units had a lower cumulative retreatment rate (4%) than those with residual fragments <2 mm (33%) or ≥2 mm (30%; P = .001). When controlling for residual fragment size, renal units that were composed of uric acid or struvite had an expected hazard rate of retreatment 3.34 times larger than renal units composed of calcium oxalate/phosphate (P = .02) and renal units that were not stone free had an expected hazard rate 7.87 times larger than renal units that were stone free (P = .001). CONCLUSION: In this population of complex stone patients treated by PCNL, there appears to be no such thing as an "insignificant fragment." Efforts at initial stone clearance should be maximized.