Clinical trial NCT01759940: Influence of the Concentration of the Local Anesthetic Ropivacaine on the Quality of a Ultrasound Guided Intermediate Cervical Block.
Official title: Influence of the Concentration of the Local Anesthetic Ropivacaine on the Quality of a Ultrasound Guided Block of the Regio Collis Lateralis for Carotid Endarterectomy: a Prospective, Randomized and Controlled Trail
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Intermediate Cervical Plexus Block for Carotid Endarterectomy
Keywords: carotid
endarterectomy
cervical block
Lead sponsor: Salzburger Landeskliniken
Sponsor class: OTHER
First posted: 2013-01-03
Enrollment: 46
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Carotid endarterectomy is commonly performed under cervical plexus block. This is presumed to offer advantages over general anesthesia in terms of monitoring neurological function during cross-clamping of the carotid artery since, in conscious patients, speech, cerebration, and motor power provide early measures of inadequate cerebral perfusion. Some studies also claim lower shunting requirements, lower cardiovascular morbidity, and shorter hospital stay.

Traditionally, the common methods of cervical plexus block are termed 'deep' or 'superficial'. The deep block, as described by Moore or Winnie and colleagues, consists of identifying the transverse processes of upper cervical vertebrae C2 - C4 and injecting local anesthetic directly into the deep (prevertebral) cervical space. This may be achieved either as separate injections or as a single injection. The superficial block incorporates a variety of procedures. The simplest is a s.c. infiltration of local anesthetic along the posterior border of sternocleidomastoid muscle by either the surgeon or the anesthetist.

An 'intermediate' block is one where the injecting needle pierces the investing fascia of the neck, deep to the s.c. layer, but superficial to the deep cervical (prevertebral) fascia. It is also possible to use a 'combined block', consisting of a deep injection and a superficial or intermediate injection.

Practitioners may prefer one block to another, but no consensus exists on the efficacy of one block when compared with another. However, it has been suggested that complications of the technique are related to the deep injection and not the superficial (or intermediate) injection. These complications include intrathecal or intravascular injection, respiratory problems related to phrenic nerve paralysis, or local anaesthetic toxicity.

In this study the Influence of the concentration of the local anesthetic ropivacaine on the quality of the intermediate cervical plexus block for carotid endarterectomy will be evaluated. For this purpose two different concentrations of ropivacaine will be compared (3,75% vs 7,5%). The primary endpoint of the study will be the quantity of the additional needed local anesthetic to achieve adequate operative analgesia. Furthermore we will record the frequency of the most common side effects as well as the patient satisfaction with a standardized questionnaire.


Eligibility criteria: Inclusion Criteria:

* patients scheduled for carotid endarterectomy in regional anesthesia

Exclusion Criteria:

* refusal to participate in the trail
* age \< 18a
* gestation/breastfeeding
* contraindication for regional anesthesia
* inclusion in other trails

Primary outcomes:
measure: amount of additional needed local anesthetics by the surgeon
timeFrame: The primary endpoint will be evaluated continuously during the ongoing surgery by interrogating the patients pain scale every two to five minutes. In average the whole procedure will take 30 to 50 minutes.
Secondary outcomes:
measure: plasma concentrations of ropivacaine
timeFrame: until 8h postoperative
measure: vital signs
timeFrame: whole day of surgery
measure: effect on the diaphragm function
timeFrame: until 6 h postoperative
Other outcomes:
Locations:
city: Salzburg
country: Austria
facility: Klinik für Anästhesiologie, perioperative Medizin und allgemeine Intensivmedizin
Study officials:
affiliation: Salk Institute for Biological Studies
name: Andreas Kokoefer, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Kokofer A, Nawratil J, Felder TK, Stundner O, Mader N, Gerner P. Ropivacaine 0.375% vs. 0.75% with prilocaine for intermediate cervical plexus block for carotid endarterectomy: A randomised trial. Eur J Anaesthesiol. 2015 Nov;32(11):781-9. doi: 10.1097/EJA.0000000000000243.