To investigate the effectiveness of ultra-Sound guided Erector spinae block (ESB) with Betamethasone as an adjuvant to standard medical protocol in the management of truncal chronic post herpetic neuralgia.
Patients age between 18 and 75.
Patients with American Society of Anesthesiologists (ASA) II and III status.
Patients diagnosed with truncal chronic post herpetic neuralgia( neuropathic pain persistent for more than 3 months from the onset of rash appearance )
Patients unable to comprehend the informed consent.
Patients on long term opioid regimens.
Patients with impairment in hepatic (Alanine aminotransferase (ALT) >50 U/L, and/or Aspartate aminotransferase (AST): >45 U/L) or renal functions( creatinine level ≥1.5 mg/dL)
Patients on anti-coagulation regimens.