Background: Quantitative train-of-four (TOF) monitoring remains essential in optimizing anesthetic outcomes by assessing the depth and recovery from neuromuscular blockade. Despite this, residual neuromuscular blockade, defined as a TOF ratio <0.90, remains a concern in both adult and pediatric patients. Quantitative TOF monitoring has seen limited use in infants and children primarily due to a lack of effective equipment. This study evaluates a new electromyography (EMG)-based TOF monitor in pediatric patients undergoing inpatient surgical procedures including laparoscopic (restricted arm access) surgery. Methods: Pediatric patients undergoing inpatient surgery requiring the administration of neuromuscular blocking agents (NMBAs) were enrolled. The EMG electrodes were placed along the ulnar nerve on the volar aspect of the arm to provide neurostimulation. The muscle action potentials from the abductor digiti minimi muscle were recorded. Neuromuscular responses were recorded by the device throughout surgery at 20-s intervals until after tracheal extubation. Data recorded on the monitor's built-in memory card were later retrieved and analyzed. Results: The study cohort included 100 pediatric patients (62% male). The average age was 11 years (IQR: 8, 13) and the average weight was 39.6 kg (30, 48.7). Automatic detection of supramaximal stimulus was obtained in 95% of patients. The muscle action potential mean baseline amplitude (in mV) was 7.5 mV (6, 9.2). The baseline TOF ratio was 100% (100, 104). After administration of a neuromuscular blocking agent, monitoring of the TOF ratio was successful in 93% of the patients. After antagonism of neuromuscular blockade, monitoring was possible in 94% of patients when using an upgraded algorithm. The baseline amplitude recovered to 6.5 mV (5, 7.8), and the TOF ratio recovered to a mean of 90.1% (90,97) before tracheal extubation. Conclusion: Our results indicate that neuromuscular monitoring can be performed intraoperatively in pediatric patients weighing between 20 and 60 kg using the new commercially available EMG-based monitor. Automatic detection of neuromuscular stimulating parameters (supramaximal current intensity level and baseline amplitude of the muscle action potential) by an adult neuromuscular monitor is feasible in pediatric patients receiving nondepolarizing neuromuscular blocking agents.

Growth of Renibacterium salmoninarum was compared in 14 different broth media; 13 serum-free, and 1 that contained newborn calf serum, KDM2+M. Supplementation with 1 % v/v R. salmoninarum MC04M metabolite was evaluated for 6 of the media that do not utilize it as part of their ingredients. Viable cells were enumerated on Days 10, 20, and 30 post inoculation to evaluate performance. The experiment was repeated 3 times using high, low, and medium (trials 1 to 3, respectively) cell concentrations as inoculum. In general there was no optimal medium and all performed well. The choice of which to employ depends on the ease of preparation and presence of certain ingredients that might affect subsequent assays. In trials 2 and 3, the pH was estimated using test papers at the same time as cells were counted. Maximum pH increase occurred with KDM2+M and those media containing charcoal. For most media, a simple pH determination could be used as a means to check that growth has occurred in a culture, particularly if charcoal was added directly to the media and a visual inspection could not be made to detect growth.KEY WORDS: Renibacterium salmoninarum . Bacterial k d n e y Disease. Broth media Serum free

No abstract

Pneumorrhachis (PR) is a rare phenomenon in which air is present in the spinal canal. PR can be stratified into different categories based on etiology, with spontaneous PR being the least common. In this report, we describe the case of a 33-year-old male with a four-year history of emesis secondary to chronic gastroparesis who presented with pleuritic chest pain radiating to the neck. A CT scan of the chest showed pneumomediastinum, with air extending into the soft tissues of the neck and the spinal canal. A literature review found a trend between maneuvers that increase intrathoracic pressure, such as emesis or coughing, and the incidence of spontaneous pneumomediastinum, in which air may freely communicate with the epidural space of the spinal canal. Currently, there are no guidelines for the management of patients with PR. From our experience, conservative management of asymptomatic PR is an appropriate approach for these patients.

Regional anesthesia is being used more frequently in the practice of pediatric anesthesia including neonates and infants. While generally safe and effective, adverse effects may occur related to catheter placement or its subsequent use. We present the rare occurrence of high motor blockade with apnea following the administration of a bolus dose of the local anesthetic agent, 2-chloroprocaine, into the thoracic epidural catheter of a 4-week-old, 2.2-kg former premature neonate. The patient had an epidural catheter that had been threaded from the caudal space to the thoracic level to provide analgesia following an abdominal surgical procedure. Subsequent investigation with a standard chest radiograph revealed a higher than intended placement of the epidural catheter (T4 instead of T8-10) which resulted in a transient high motor blockade with apnea. The epidural infusion was discontinued and assisted ventilation was provided by bag-valve-mask ventilation. Immediately, the heart rate and oxygen saturation returned to baseline values, and within 5 min the patient became more active, spontaneous ventilation resumed, and a strong cry was noted. The epidural catheter was removed and the remainder of the postoperative course was unremarkable. Adverse effects of epidural anesthesia in neonates are discussed and options for identifying the correct placement of a thoracic epidural catheter are reviewed.