İnfraklavikular brakial pleksus bloğunda kostoklavikular yaklaşımların geleneksel lateral sagittal tekniğe karşı etkinliğinin ve performans özelliklerinin karşılaştırılması: Randomize kontrollü çalışma

Background and Aim: Blocking brachial plexus with an intracluster injection in the costoclavicular fossa has been defined recently. Here, it is aimed to compare infraclavicular techniques including lateral versus medial approach costoclavicular, and traditional lateral sagittal approach. A quicker sensory block onset time was hypothesized on behalf of lateral costoclavicular approach.Methods: After obtaining ethical approval and clinicaltrials.gov registry, blocks were performed according to randomization. For the lateral sagittal block (LSB), two separate local anaesthetic (LA) injections were made posterior and medial aspect of the subclavian artery. For costoclavicular blocks, single LA injection were administered into the triangular cluster of cords, and defined costoclavicular lateral block (CLB) or costoclavicular medial block (CMB) according to the direction of needle placement. Sensory and motor block onset times, block performance properties (ideal ultrasound visualization time, number of needle maneuvers, need for additional needle maneuver, number of injections, perceived difficulty of performance), and time to regain sensory and motor activity were investigated.Results: Demographics were presented in Table 1. Sensory onset was fastest in CLB group (n=18) comparing to LSB group (n=20), and also CMB group (n=18) (10[5-15] vs 15[10-15], and 10[10-20] minutes, respectively, p=0.01) (Figure 1A). This was also valid for motor block onset (15[10-20], 20[15-20], and 22.5[15-25] minutes, respectively, p=0.004). Block performance properties and comfort parameters did not differ between the three groups (Table 2). Both motor and sensory activity were returned in between 12th and 18th hours, and were similar in all groups (Figure 1B).Conclusion: Lateral approach to costoclavicular block exhibited faster sensory and motor block onset than medial costoclavicular and lateral sagittal approach. All techniques were similar in terms of performance properties, and demonstrated similar perioperative comfort

The neurotoxic effects of intrathecal midazolam and neostigmine in rabbits

In parallel with improvements in understanding pain neurophysiology, many chemicals have recently been investigated for spinal anaesthesia and analgesia. However, studies discussing the effects of these drugs on neural tissue indicate that knowledge about some aspects of neurotoxicity is limited. Forty-nine New Zealand albino rabbits, weighing 2.2+/-0.2 kg, were randomly assigned to seven groups of seven animals each. Single dose groups received intrathecally through the atlantooccipital membrane 0.9% saline 1.5 ml; midazolam 100 mu g/kg (low dose midazolam group) or 500 mu g/kg (high dose midazolam group); neostigmine 10 mu g/kg (low dose neostigmine group) or 50 mu g/kg (high dose neostigmine group). Two groups had seven days of repeated dosing with either midazolam 100 mu g/kg/day (repeat midazolam group) or 10 mu g/kg/day neostigmine (repeat neostigmine group). The animals were sacrificed on day 8, and two spinal cord sections from the fourth cervical level and fourth lumbar level were removed and prepared for histopathological study. Transmission electron microscopic evaluations were performed on transverse spinal cord sections by a neuropathologist blinded to the group allocation. Twenty myelinated axons and neurones in the cervical and lumbar sections were investigated for the histopathological study. This study indicates that midazolam and neostigmine have different neurotoxic effects that depend on the dose and the repetition of dosing when these drugs arc, administered intrathecally