What are your recommendations in the context of your practice.

Hello to all When a letter with a recommendation from an allergy MD is presented by a patient, is wise to use other anesthesia & analgesia technique in spite of Anesthesiologyst preferences and experience. Hypothetically any complication related or not to allergy, could be difficult to explain or legally defend.  If there is enough time, repeat the test and include other LA, if there is not enough time general anesthesia and spinal morphine & and PO IV NSAIDs + rescue opiods could be also a good option. Best  Carlos

Anesthesiologists using peripheral nerve stimulation (PNS), classically deal with an end point for injection of 0.5 mA, 100 msec, 2 Hz, with no paresthesia, pain on injection, without undue pressure and disappears with 0.3 mA. Virtually no work or article on electrical nerve stimulation (PNS) refers to the characteristics of the motor response (MR) obtained by referring only to the muscle group involved in the stimulation of that nerve. Of subjectivity in interpreting the intensity of muscle contraction depends also much the success of a blockade. The intensity of muscle contraction depends on the number of motor axons influenced by the electric field, the greater the number of motor axons stimulated much larger muscle fibers and muscle contraction. The needle + the intensity of the current (electric field), on the one hand, the distance traveled by another and the number of stimulated motor axons eventually give the degree of contraction to be interpreted. Grade 0 = no MR Grade 1 = mild MR Grado2 = intense RM  Grade 3 = maximum RM. We should also know that is not always means the same a Grade 2 MR at the interscalene that at a sciatic level, since the composition of each nerve bundle is not the same. You can get an MR Grade 1 or 2 level and 0.5mA at an  interscalene block, with the needle will clearly further away from the nerve when you get a grade 1 RM. For example, at the sciatic parasacral blocks we noted that even with a MR grade 1 with 1 mA blocks are effective and on the other hand we have obtained simultaneously Grade 2 MR with 0.5mA and simultaneously pain and paresthesia, indicates an undesirable closer contact with the nerve. Opinions? what is your usual practice? Do you Agree? Ultrasonography gives us more information? what happens with different nerves eg axillary, femoral, popliteal, infraclavicular, supraclavicular? Best regards      

For Interscalene and supraclavicular blocks I prefer a combination of local anesthetics. First an injection of mepivacaine 1% with epinefrine and then ropivacaine 0.75%.  Wich are your options and preferred method.

In the `90´s we used isobaric 2% lidocaine in young ambulatory patients for some cases of simple arthroscopic knee surgery and mainly inpatient ACL repair (via a 27G fine needle in a CSE). No patient reported symptoms of TRI.  Since 2000, after the works of Pollock et al and Salazar et al. were published, we discontinued its´ use for young ambulatory arthroscopic patients. From 2000 up today, I still use isobaric 2% occasionally in selected ambulatory patients (>70y, ambulatory short duration lower limb procedures).  Best Carlos