Lumbosacral plexus and pudendal nerve magnetic resonance tractography: A systematic review of the clinical applications for pudendal neuralgia.

Diffusion tensor imaging (DTI) is commonly used to establish three-dimensional mapping of white-matter bundles in the supraspinal central nervous system. DTI has also been the subject of many studies on cranial and peripheral nerves. This non-invasive imaging technique enables virtual dissection of nerves in vivo and provides specific measurements of microstructural integrity. Adverse effects on the lumbosacral plexus may be traumatic, compressive, tumoral, or malformative and thus require dedicated treatment. DTI could lead to new perspectives in pudendal neuralgia diagnosis and management. We performed a systematic review of all articles or posters reporting results and protocols for lumbosacral plexus mapping using the DTI technique between January 2011 and December 2023. Twenty-nine articles published were included. Ten studies with a total of 351 participants were able to track the lumbosacral plexus in a physiological context and 19 studies with a total of 402 subjects tracked lumbosacral plexus in a pathological context. Tractography was performed on a 1.5T or 3T MRI system. DTI applied to the lumbosacral plexus and pudendal nerve is feasible but no microstructural normative value has been proposed for the pudendal nerve. The most frequently tracking parameters used in our review are: 3T MRI, b-value of 800 s/mm2, 33 directions, 3 × 3 × 3 mm3, AF threshold of 0.1, minimum fiber length of 10 mm, bending angle of 30°, and 3DT2 TSE anatomical resolution. Increased use of DTI could lead to new perspectives in the management of pudendal neuralgia due to entrapment syndrome, whether at the diagnostic, prognostic, or preoperative planning level. Prospective studies of healthy subjects and patients with the optimal acquisition parameters described above are needed to establish the accuracy of MR tractography for diagnosing pudendal neuralgia and other intrapelvic nerve entrapments.

Assessing erectile neurogenic dysfunction from heart rate variability through a Generalized Linear Mixed Model framework.

BACKGROUND: The low (LF) vs. high (HF) frequency energy ratio, computed from the spectral decomposition of heart beat intervals, has become a major tool in cardiac autonomic system control and sympatho-vagal balance studies. The (statistical) distributions of response variables designed from ratios of two quantities, such as the LF/HF ratio, are likely to non-normal, hence preventing e.g., from a relevant use of the t-test. Even using a non-parametric formulation, the solution may be not appropriate as the test statistics do not account for correlation and heteroskedasticity, such as those that can be observed when several measures are taken from the same patient. OBJECTIVES: The analyses for such type of data require the application of statistical models which do not assume a priori independence. In this spirit, the present contribution proposes the use of the Generalized Linear Mixed Models (GLMMs) framework to assess differences between groups of measures performed over classes of patients. METHODS: Statistical linear mixed models allow the inclusion of at least one random effect, besides the error term, which induces correlation between observations from the same subject. Moreover, by using GLMM, practitioners could assume any probability distribution, within the exponential family, for the data, and naturally model heteroskedasticity. Here, the sympatho-vagal balance expressed as LF/HF ratio of patients suffering neurogenic erectile dysfunction under three different body positions was analyzed in a case-control protocol by means of a GLMM under gamma and Gaussian distributed responses assumptions. RESULTS: The gamma GLMM model was compared with the normal linear mixed model (LMM) approach conducted using raw and log transformed data. Both raw GLMM gamma and log transformed LMM allow better inference for factor effects, including correlations between observations from the same patient under different body position compared to the raw LMM. The gamma GLMM provides a more natural distribution assumption of a response expressed as a ratio. CONCLUSIONS: A gamma distribution assumption intrinsically models quadratic relationships between the expected value and the variance of the data avoiding prior data transformation. SAS and R source code are available on request.

[Propofol versus etomidate in short-time urologic surgery]. / Propofol versus étomidate en chirurgie urologique de courte durée.

Thirty patients, scheduled for short urological surgical procedures and ranked ASA 1 or 2, were randomly assigned to two homogenous groups. In group P, they were given a 2 mg.kg-1 bolus of propofol and 10 micrograms.kg-1 of alfentanil, followed by a continuous infusion of propofol (5 mg.kg-1.h-1) and 5 micrograms.kg-1 doses of alfentanil. In group E, they were given a 0.3 mg.kg-1 bolus of etomidate, followed by an infusion (1.5 mg.kg-1.h-1). The doses of alfentanil were the same as in group P. Further doses of either propofol (0.5 mg.kg-1) or etomidate (0.2 mg.kg-1) were used should anaesthesia prove not to be deep enough. The patients were not intubated, and breathed spontaneously. Surgery lasted a mean of 18.3 +/- 11.8 min (group P) and 18.8 +/- 9.4 min (group E). The following parameters were studied: the amount of each agent required for maintenance of anaesthesia, the duration of apnoea at induction, the quality of anaesthesia and of muscle relaxation, adverse effects (coughing, trismus, restlessness, nausea, vomiting), the time required for recovery, and its quality. In group P, there was a 27% decrease in arterial pressure, without any tachycardia or hypoxia, together with a quick recovery of excellent quality. On the other hand, in group E, there was little or no haemodynamic alteration, but there often was a trismus at induction. Hypoxia also occurred during induction with etomidate, being severe enough in one case to require tracheal intubation and artificial ventilation. The reasons for this hypoxia seemed to be the apnoea and the trismus, which tends to hinder assisted ventilation.(ABSTRACT TRUNCATED AT 250 WORDS)

[Postoperative analgesia for nephrectomy]. / Analgésie postopératoire pour la néphrectomie.

The aim of this study of post-nephrectomy acute pain in 30 patients was to compare three methods of postoperative analgesia and determine which one could be the most satisfactory. Ten patients received epidural analgesia with pethidine (400 mg.24 h-1 for 48 hrs). Ten other patients received intrapleural analgesia with bupivacaine (0.2 mg.kg-1.h-1 of 0.5% bupivacaine with 1/200,000 epinephrine). The ten remaining patients received systemic IV analgesia (2 g of propacetamol every 6 hrs and 0.15 mg of buprenorphine every 6 hrs). According to results of pain evaluation score (VAS) epidural analgesia with pethidine (VAS less than 2.5) appeared to be the best tested analgesic method. IV systemic analgesia (VAS less than 5) was less effective. Intrapleural bupivacaine (VAS greater than 5) was ineffective but apparently not toxic (serum concentration less than 1,200 ng.ml-1).

[Antibiotic prophylaxis with cefotiam in transurethral resection of the prostate]. / Antibioprophylaxie par le céfotiam pour la résection trans-uréthrale de la prostate.

UNLABELLED: Over a period of 7 months, 50 patients underwent a trans-urethral resection of the prostate (TURP), this intervention is classified as "clear-contamined". The antibiotic prophylactic protocol, the subject of this study, was the following: cefotiam 2 g IV with the induction of anesthesia, 1 g 3 hours later and 1 g IV with the removal of the urethral catheter. RESULTS: there were 3 early post-operative urinary tract infections, one of these patients was symptomatic, at the time of removal of the urethral catheter. Most of these infections were due to Enterococcus faecalis bacteria. There was 4 late post-operative symptomatic urinary tract infections at days 15, 20, 50, and 120 respectively. All these late infections were due to Streptococcus faecalis. In total, there was a 10% rate of urinary tract infections in the critical 30 days period following the TURP. All the blood cultures were negative. These results lead us to conclude that the short term preventive treatment using the cefotiam, cephalosporin which has a strong prostatic tissue penetration, reduces the rate of post TURP urinary tract infections.

[Antibiotic prophylaxis with cefotiam in percutaneous nephrolithotomy]. / Antibioprophylaxie par le céfotiam pour la néphrolithotomie percutanée.

The percutaneous extraction of renal calculi in patients whose urines are sterile is considered to be a "clean-contaminated" surgery. The post-operatory infection is thought to be the result of the urethral catheter and the nephrostomy tube. The bacteria that are more after implicated are the Gram-negative bacteria. Therefore we found useful to give as a prophylactic treatment cefotiam, which is a 3rd generation cephalosporin, and have the advantage or reaching elevated urinary concentration as well as having a broad-spectrum activity on both Gram-negative bacteria and Staphylococcus. It has been used as follow: 1) with the anesthetic induction give 2 g IV push; 2) these give 1 g IV 12 hourly four times. It has been noted, that in all patients receiving this regimen, no post-operatory infection or urinary tract infection was found during the 48 hours following surgery. Therefore we think that due to the reasonable cost of the regimen, we advise it for this type of surgery.

Atracurium in patients with renal failure. Clinical trial of a new neuromuscular blocker.

Atracurium was given to 30 patients with terminal chronic renal insufficiency, in two regimens. Group I (20 patients) received a single dose of 0.6 mg kg-1 and group II (10 patients), received one or several injections of 0.2 mg kg-1. Tracheal intubation was performed with ease in all patients 3 min after the injection of atracurium. A supramaximal stimulus was applied to the ulnar nerve at wrist level, and thumb adduction force was recorded. Muscular blockade was 100% in 29/30 patients and 95% in one. Mean time between atracurium injection and reappearance of 25% of the initial muscular power (HT25) was 49 min. The recovery time index (IR25-75) was 12 min and did not increase after re-injection. No side-effects were observed and no significant differences in any of the measurements made were seen between the two groups.