Ultrasound-guided pudendal nerve block in cats undergoing perineal urethrostomy: a prospective, randomised, investigator-blind, placebo-controlled clinical trial

The objective of this study was to evaluate the clinical usefulness, in terms of analgesic efficacy and safety, of ultrasound-guided pudendal nerve block performed with bupivacaine in cats undergoing perineal urethrostomy. Eighteen client-owned male cats scheduled for perineal urethrostomy were enrolled in the study and assigned to one of two treatment groups. The pudendal nerve block was performed under general anaesthesia as described elsewhere, with 0.3 ml/kg of either saline (group C) or 0.5% bupivacaine (group B) - the total injection volume being split equally on the two sites of injection (left and right). Intra-operatively, assessment of nociception was based on the rescue analgesics requirement, as well as on the evaluation of changes in physiological parameters in comparison with the baseline values. Post-operative pain assessment was performed using three different pain scales at recovery and then 1, 2 and 3 h after recovery. Cats in group B showed lower heart rates and required fewer analgesics during surgery than group C. Post-operatively, group B had lower pain scores and needed less rescue buprenorphine than group C. Iatrogenic block-related complications were not observed. In conclusion, the ultrasound-guided pudendal nerve block can be considered clinically useful in feline medicine as it provides reliable analgesia in cats undergoing perineal urethrostomy.

An urn-based Bayesian block bootstrap

Block bootstrap has been introduced in the literature for resampling dependent data, i.e. stationary processes. One of the main assumptions in block bootstrapping is that the blocks of observations are exchangeable, i.e. their joint distribution is immune to permutations. In this paper we propose a new Bayesian approach to block bootstrapping, starting from the construction of exchangeable blocks. Our sampling mechanism is based on a particular class of reinforced urn processes

Association of congenital, diffuse electrical disease in children with normal heart: sick sinus syndrome, intraventricular conduction block, and monomorphic ventricular tachycardia.

INTRODUCTION Rhythm disturbances in children with structurally normal hearts are usually associated with abnormalities in cardiac ion channels. The phenotypic expression of these abnormalities ("channelopathies") includes: long and short QT syndromes, Brugada syndrome, congenital sick sinus syndrome, catecholaminergic polymorphic ventricular tachycardia, Lènegre-Lev disease, and/or different degrees of cardiac conduction disease. METHODS The study group consisted of three male patients with sick sinus syndrome, intraventricular conduction disease, and monomorphic sustained ventricular tachycardia. Clinical data and results of electrocardiography, Holter monitoring, electrophysiology, and echocardiography are described. RESULTS In all patients, the ECG during sinus rhythm showed right bundle branch block and long QT intervals. First-degree AV block was documented in two subjects, and J point elevation in one. A pacemaker was implanted in all cases due to symptomatic bradycardia (sick sinus syndrome). Atrial tachyarryhthmias were observed in two patients. The common characteristic ventricular arrhythmia was a monomorphic sustained ventricular tachycardia, inducible with ventricular stimulation and sensitive to lidocaine. In one patient, radiofrequency catheter ablation was successfully performed. No structural abnormalities were found in echocardiography in the study group. CONCLUSION Common clinical and ECG features suggest a common pathophysiology in this group of patients with congenital severe electrical disease.

Differentiating atrioventricular nodal reentrant tachycardia from tachycardia via concealed accessory pathway.

Studies analyzing the diagnostic value of 12-lead electrocardiographic criteria differentiating slow-fast atrioventricular nodal reentrant tachycardia (AVNRT) from atrioventricular reentrant tachycardia (AVRT) due to concealed accessory pathway have shown inconsistent results. In 97 patients (50 with AVNRT, 47 with AVRT) 12-lead electrocardiograms (ECGs) were recorded during sinus rhythm and tachycardia (QRS <120 ms). The ECGs were blinded for diagnosis and patient and analyzed independently by 2 electrophysiologists. The studied criteria differentiating AVNRT from AVRT included pseudo-r'/S, the presence of a retrograde P wave, RP interval, ST-segment depression >/=2 mm with the number and location of the affected leads, QRS amplitude, and cycle length alternans.

Behandlung bradykarder Rhythmusstörungen – wer benötigt einen Herzschrittmacher?

Bradyarrhythmias are caused by a disturbed impulse formation in the sinus node and/or a disturbed impulse conduction and can be subclassified clinically as sinus node dysfunction, atrioventricular (AV) block, or functional bradycardia. Persistent bradycardia can be diagnosed by standard ECG. For diagnosis of intermittent bradycardia, often long-term ECG monitoring and/or additional testing is necessary. Symptomatic bradycardias are the standard indication for cardiac pacing after exclusion of reversible causes. Since sinus node dysfunction is associated with a good prognosis, pacing in this condition is only indicated in the presence of bradycardia-related symptoms. For prognostic reasons, pacemaker implantation is indicated in third degree AV block and second degree AV block Mobitz Type II, even if asymptomatic. Cardiac pacing for recurrent unpredictable neurocardiogenic syncope due to a cardioinhibitory reflex should be considered in certain circumstances. The implantation of cardiac pacemakers has been performed for more than half of a century. Due to the enormous technological progress, pacemaker implantations can nowadays be performed under local anesthesia in an outpatient setting. However, complications of pacemaker therapy are still not uncommon.

Transition from nerve stimulator to sonographically guided axillary brachial plexus anesthesia in hand surgery: block quality and patient satisfaction during the transition period

OBJECTIVES Sonographic guidance for peripheral nerve anesthesia has proven increasingly successful in clinical practice; however, fears that a change to sonographically guided regional anesthesia may impair the block quality and operating room work flow persist in certain units. In this retrospective cohort study, block quality and patient satisfaction during the transition period from nerve stimulator to sonographic guidance for axillary brachial plexus anesthesia in a tertiary referral center were investigated. METHODS Anesthesia records of all patients who had elective surgery of the wrist or hand during the transition time (September 1, 2006-August 25, 2007) were reviewed for block success, placement time, anesthesiologist training level, local anesthetic volume, and requirement of additional analgesics. Postoperative records were reviewed, and patient satisfaction was assessed by telephone interviews in matched subgroups. RESULTS Of 415 blocks, 341 were sonographically guided, and 74 were nerve stimulator guided. Sonographically guided blocks were mostly performed by novices, whereas nerve stimulator-guided blocks were performed by advanced users (72.3% versus 14%; P < .001). Block performance times and success rates were similar in both groups. In sonographically guided blocks, significantly less local anesthetics were applied compared to nerve stimulator-guided blocks (mean ± SD, 36.1 ± 7.1 versus 43.9 ± 6.1 mL; P< .001), and less opioids were required (fentanyl, 66.1 ± 30 versus 90 ± 62 μg; P< .001). Interviewed patients reported significantly less procedure-related discomfort, pain, and prolonged procedure time when block placement was sonographically guided (2% versus 20%; P = .002). CONCLUSIONS Transition from nerve stimulator to sonographic guidance for axillary brachial plexus blocks did not change block performance times or success rates. Patient satisfaction was improved even during the early institutional transition period.

Development of an ultrasound-guided technique for pudendal nerve block in cat cadavers.

The objective of this prospective experimental cadaveric study was to develop an ultrasound-guided technique to perform an anaesthetic pudendal nerve block in male cats. Fifteen fresh cadavers were used for this trial. A detailed anatomical dissection was performed on one cat in order to scrutinise the pudendal nerve and its ramifications. In a second step, the cadavers of six cats were used to test three different ultrasonographic approaches to the pudendal nerve: the deep dorso-lateral, the superficial dorso-lateral and the median transperineal. Although none of the approaches allowed direct ultrasonographical identification of the pudendal nerve branches, the deep dorso-lateral was found to be the most advantageous one in terms of practicability and ability to identify useful and reliable landmarks. Based on these findings, the deep dorso-lateral approach was selected as technique of choice for tracer injections (0.1 ml 1% methylene blue injected bilaterally) in six cat cadavers distinct from those used for the ultrasonographical study. Anatomical dissection revealed a homogeneous spread of the tracer around the pudendal nerve sensory branches in all six cadavers. Finally, computed tomography was performed in two additional cadavers after injection of 0.3 ml/kg (0.15 ml/kg per each injection sites, left and right) contrast medium through the deep dorso-lateral approach in order to obtain a model of volume distribution applicable to local anaesthetics. Our findings in cat cadavers indicate that ultrasound-guided pudendal nerve block is feasible and could be proposed to provide peri-operative analgesia in clinical patients undergoing perineal urethrostomy.

Electron density building block approach for metal organic frameworks

A general introduction to the state of the art in modeling metal organic materials using transferable atomic multipoles is provided. The method is based on the building block partitioning of the electron density, which is illustrated with some examples of potential applications and with detailed discussions of the advantages and pitfalls. The interactions taking place between building blocks are summarized and are used to discuss the properties that can be calculated.