Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Randomized, Subject-Masked, Active-Controlled, Parallel-Arm Clinical Trial Comparing Erector Spinae and Paravertebral Nerve Blocks
Brief Summary: Following painful surgical procedures of the breast, postoperative analgesia is often provided with a paravertebral nerve block (PVB). For intense, but shorter-duration acute pain, a single-injection of local anesthetic is used with a duration of approximately 12 hours. The PVB has several limitations: it can decrease blood pressure, and very rare-but serious-complications have occurred, including neuraxial injection, neuraxial hematoma, and pleural puncture. An alternative block has been described: the erector spinae plane block. The theoretical benefits include ease of administration since it is a plane superficial to the PVB and therefore easier to identify and target with ultrasound (therefore increasing success rate); and an increased safety margin: there are few anatomic structures in the immediate area which could be injured with the needle; and, the target plane is much further from the intrathecal/epidural space relative to the PVB. Lastly, the plane may be easier to catheterize for continuous peripheral nerve blocks relative to the relatively-small volume PVB.

There are therefore multiple theoretical reasons to prefer the erector spinae plane block. Unfortunately, it remains unknown if the analgesia provided by this new technique is comparable to that provided with the PVB. The investigators therefore propose to compare these two techniques with a randomized, subject-masked, active-controlled, parallel-arm, human subjects clinical trial.


Options:
A: Inclusion Criteria:Male and Female participants providing written informed consent, ASA grade 1- 4, age group 18 and over undergoing Posterior approach Spinal surgery involving 2 or more levels of decompression in the lumbar or thoracic regions.

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Exclusion Criteria:Absence of informed written consent, pre existing infection at block site, severe coagulopathy, allergy to local anaesthesia, , previous history of opiate abuse, pre existing chronic pain condition, pre-existing dementia \[because of need to co-operate in completing QoR-15 score day after surgery\], decompression involving cervical levels of vertebrae, decompression due to queried or confirmed malignancy

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B: Inclusion Criteria:

* undergoing unilateral or bilateral breast surgery with at least moderate postoperative pain anticipated
* analgesic plan includes a single-injection peripheral nerve block(s)
* age 18 years or older.

Exclusion Criteria:

* morbid obesity as defined by a body mass index \> 40 (BMI=weight in kg / \[height in meters\]2)
* renal insufficiency (preoperative creatinine \> 1.5 mg/dL)
* chronic opioid use (daily use within the 2 weeks prior to surgery and duration of use \> 4 weeks)
* history of opioid abuse
* any comorbidity which results in moderate or severe functional limitation
* inability to communicate with the investigators or hospital staff
* pregnancy
* planned regional analgesic with perineural catheter placement
* incarceration
C: Inclusion Criteria:

* 60 ASA I- II adult patients
* 20-60 years old
* elective laparoscopic cholecystectomy
* Body mass index (BMI) less than 35
* Port sites at or above thoracic T 10 dermatome

Exclusion Criteria:

* Allergy to amino-amide local anesthetics
* Presence of coagulopathy
* Local skin infection at the needle puncture sites
* Preoperative chronic dependence upon opioid and NSAID medications
* Liver or renal insufficiency
* History of psychiatric or neurological disease
* Deafness
* previous open surgery that need the conversion of laparoscopic to open surgery or manipulations more than expected with more tissue trauma
* American Society of Anesthesiologists (ASA) above Class II
D: Inclusion Criteria:

* ASA I-II
* Age 18-65 years
* Undergoing elective lomber disc hernia

Exclusion Criteria:

* obesity
* ASA III - IV
* infection of the skin at the site of needle puncture area
* patients with known allergies to any of the study drugs
* coagulopathy

Answer: B