Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Simonis, H.
Safety and efficacy of blocking the obturator nerve for regional anaesthesia based on new anatomical findings
Doktoratsstudium der Medizinischen Wissenschaft; Humanmedizin; [ Dissertation ] ; 2015. pp.
[OPEN ACCESS]
FullText
- Autor*innen der Med Uni Graz:
- Betreuer*innen:
- Kresse Adelheid
- Rigaud Marcel
- Sandner-Kiesling Andreas
- Altmetrics:
- Abstract:
- Background and Objectives: The Institute of Anatomy at the Medical University of Graz developed a new approach for the obturator nerve block (Vertical Obturator Nerve Block; VOB). Promising results on 88 cadavers (=176 lower limbs) encouraged us to test this new technique in patients in our daily hospital routine. Methods: A prospective, 2:1 (verum/control group, n=30) randomized, double-blind, parallel designed pilot trial was approved by our Institutional Ethics Committee and registered at clinicaltrials.gov (NCT01875289). All patients received a VOB. We used 5 ml 0.75 % ropivacaine (37.5 mg) in the verum group and 5 ml 0.9 % sodium chloride in the control group. The primary outcome was adductor muscle strength before and 15 minutes after nerve block, and the difference between both groups. The adductor muscle strength was measured with a manual sphygmomanometer. Results: The difference between groups was not significant (p=0.074). A successful obturator nerve block was observed in the verum group (n = 3), but not in the control group (n = 0), based on a cut off at 50 % decrease in muscle strength. The prep time before needling was 97.5±96.8 seconds (mean; SD). The needle-in-body time was 32.4±18.3 seconds. The whole nerve block took 129.8±100.7 seconds. Mean patient's pain intensity during needling was 2.9±1.73 on a Numeric Rating Scale (0-10). Every patient would be willing to agree to receive this nerve block again in future. Conclusions: The VOB is a simple, painless and outstanding fast nerve block compared to the common obturator nerve blocks. The low success rate can be improved substantially by minor technical modifications. We will use electro-stimulation plus/minus ultrasound targeting, higher volume of local anaesthetics and additional measurements later after nerve block in future to increase the success rates.