MOHAMED MOUSSA, M. E.; AWAD, H. G.; HAMID, H. S.; ABDELLATIF, A.; SHARAF, A. A comparative study between femoral nerve block and intravenous ketamine for pain management during positioning for spinal anesthesia in elderly patients with femur fracture. Anaesthesia, Pain & Intensive Care, v. 26, n. 3, p. 297-303, 13 jun. 2022.