Prior to surgery, patients will be stratified into groups according to the type of surgical procedure. The anticipated groups are as follows:

Patients with colorectal cancer

Patients with prostate cancer

Patients with renal cancer

Patients undergoing surgery for gallbladder cholelithiasis. The Erector Spinal Block (ESP) is based on the deposition of the local anesthetic in the inter-fascial space between the dorsal extensor muscle and the intercostal muscles at the height of the transverse processes. The scope of the blockade covers the dorsal and ventral branches of the thoracic spinal nerves, but also in most cases the investigetors are able to obtain a wide distribution of the drug into the paravertebral space by "permeating" the local anesthetic through the fascial compartments. The clinical effect of the blockade is due to blocking the nerve structures of the paravertebral space (spinal nerve branches and the sympathetic trunk). The scope of the blockade, after its execution at the level of Th5, most often includes the segments from Th1 to L1.

Currently, the Quadratus Lumborum block (QL block) is performed as one of the perioperative pain management procedures for all generations (pediatrics, pregnant, and adult) undergoing abdominal surgery. The local anesthetic injected via the approach of the anterior QL block ( QL1 block ) can more easily extend beyond the TAP to the thoracic paravertebral space or the thoracolumbar plane, the posterior QL block entails a broader sensory-level analgesic and may generate analgesia from T7 to L1.

In abdomen surgery, overall pain is a conglomerate of three different and clinically separate components: incisional pain (somatic pain), visceral pain (deep intra abdominal pain), and shoulder pain due to peritoneal stretching and diaphragmatic irritation associated with carbon dioxide insufflation. Moreover, it has been hypothesized that intense acute pain after labdomen surgery may predict development of chronic pain. Without effective treatment, this ongoing pain may delay recovery, mandate inpatient admission, and thereby increase the cost of such care.

Inclusion Criteria:

• Patients requiring abdomen surgery
• Patients of age 18 and over
• BMI < 40
• Patients who are expected to stay in-hospital overnight after surgery

Exclusion Criteria:

• Patient refusal
• Contraindications to paravertebral blocks: Infection at the site of needle insertion, empyema, allergy to local anesthetic drugs, and tumor occupying the thoracic paravertebral space, coagulopathy, bleeding disorder or therapeutic anticoagulation
• Known allergy to local anesthetics
• Inability to provide informed consent
• Inability to use a PCA due to languate or comprehension barriers
• BMI >= 40
• Any patient on opioids for greater than or equal to 3 months duration prior to surgery
• Patients with chronic pain syndromes

Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)