Analgesic Efficacy of Transmucosal Fentanyl for Breakthrough Pain Caused by Interventional Gastrostomy

Patients with Head \& Neck Squamous Cell Carcinoma often need a gastrostomy. It can be performed with a radiological approach. This procedure is usually not performed under general anesthesia, but local anesthesia is not sufficient to counteract pain due to gastric insufflation and incision of the abdominal wall. Standard analgesic treatments are usually not well-fitted due to onset of action or route of administration. An alternative solution could be fentanyl nasal spray, a treatment with a fast onset of action and with easy use allowing repetition if needed, during the procedure. The purpose of this study is to compare analgesic efficacy of nasal instillation of PECFENT® to usually administered morphinic analgesic treatment with fast onset of action (ORAMORPH®), in radiologic percutaneous gastrostomy tube placement: * during the procedure * following the procedure (measured by Visual Analog Scale (VAS) for Pain at 15 min, 30 min, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours and 12 hours after procedure). Secondary purposes are to compare easiness of 2 treatments and their adverse effects.