PECS II Block in Thoracic Outlet Decompression

Rationale: Postoperative pain management after transaxillary thoracic outlet decompression surgery (TATOD) is difficult. In a retrospective case-control trial, we found evidence that a PECS II block is able to reduce pain and morphine consumption. This may ultimately lead to less morphine induced side-effects and improved patient satisfaction. However, the risk of bias in retrospective research is high. To determine the effect of PECS II in TATOD, a randomized controlled double blinded trial could offer more valuable scientific evidence. Our hypothesis is that a PECS II block will reduce pain, opioid use and opioid induced side-effects in patients undergoing transaxillary TOD (TATOD).

Objective: The aim of the study is to determine the effect of a PECS II block on postoperative pain and opioid use in patients undergoing TATOD. The secondary objective is to determine the effect of a PECS II block on opioid induced side effects such as postoperative nausea and vomitus and the quality of recovery Study design: Single centre randomized controlled double blinded trial Study population: All patients with Neurogenic Thoracic Outlet Syndrome (NTOS) selected for TATOD by the TOS multidisciplinary workgroup and based on the specifications in 2016 SVS reporting standards.

Intervention: The study group will receive a PECS II block with 40 ml ropivacaine 5 mg/ml. The control group will receive a PECS II block with 40 ml NaCL 0.9%.

Main study parameters/endpoints: Primary outcome parameters are postoperative pain using the Numeric Rated Scale (NRS) score assessed at rest and when moving and postoperative morphine-equivalent consumption. Secondary outcome parameters are postoperative Nausea and Vomitus (PONV) and Quality of Recovery questionnaire (QoR-15).

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: All patients will undergo ultrasound guided injection, after induction of anaesthesia. The administration of the injection does not invoke any extra physical discom-fort. Possible complications include hematoma and pneumothorax, however, the risk is very low (\<1%)\[1\]. In the intervention group, we expect less pain, a reduced need for pain medica-tion and less postoperative nausea and vomitus. We do not expect an altered postoperative course in the control group. Patients will be asked to fill out a questionnaire. Extra blood sam-ples, site visits, physical examinations or other test will not be done in this study.


Eligibility Criteria:
Inclusion Criteria:

* Patients with NTOS
* Selected for a trans-axillary thoracic outlet decompression (TATOD) by the TOS multidisciplinary workgroup.
* Fit for surgery, defined as ASA (American Society of Anesthesiologists) Classification of I, II or III.
* 18 years of age or older
* Sufficient in speaking and writing the Dutch language
* Normal liver and renal function
* Informed consent

Exclusion Criteria:

* Patients with a history of TOD (Redo-surgery)
* Patients with ATOS or VTOS
* ASA ≥ 4
* Kidney or liver failure with contra-indication for NSAID or paracetamol
* Mental retardation
* Pregnancy
* Patients with chronic strong opioid use (\>3 administrations per week or continuous transdermal therapy, longer than the last 3 months)
* Allergy to one or more medications used in the study including, ropivacaine, dexamethasone, propofol, sufentanil, succinylcholine, paracetamol, NSAID, morphine, granisetron
* Patients that have trouble expressing themselves in Dutch. Questionnaires are completed by the patients and checked by the nurses. The questionnaire is in Dutch. If there is a language barrier between the questionnaire, the patient or the health care worker, we believe the validity of the answers is questionable.