Obstetrics anesthesia and analgesia Dr.Nawal Alsinani

Analgesia : Loss of perception of pain. Anesthesia : Loss of ability to perceive touch – pain and other sensation.

General consideration 1 – two person to be consider. 2- respiratory center of the infant is highly vulnerable to sedative and anesthetic. 3 – duration of administration. 4 – patient preparation.

Anatomy of pain 1 – pain in first stage of labour. L1 – T10 – T11 – T12. 2 – sensory pathways : - Uterine plexus. - Inferior hypo gastric plexus. - Midle and superior hypo gastric. - Lumbar and lower thoracic symptathetic chain

2 – pain in the 2 nd stage - branches of the pudendal nerve. - Conveyed along nerve roots S2-S3 –S4 - Other nerves as the ilioinguinal nerve – genitofemoral nerves.

Techniques of analgesia without the use of drugs * Psychoprophylaxis * hypnosis

Analgesic, amnestic and anesthetic agents * General comments and precautions : 1- prepare patient psychologically. 2- individualize the treatment of every patient. 3- know the drugs. 4- all systemic drugs cross the placenta. 5- No drugs has selective maternal effects.

Pharmacologic aspects 1- route of administration : - Oral,I.M, I.V. 2- placental transfer.

Specific types of analgesic agents 1- Inhalant agents : - Nitrous Oxide ( 50% N2O + 50% O2 ) Good in 1 st stage of labor. 2- Sedatives : * Produce drowsiness * Slow

3- tranquilzers and amnestics : - Relieve apprehension Eg. Valium : If given early can cause Kernicterus. 4- Narcotic Analgesics : - Used in 1 st stage of labor. Eg. Morphine : If given early can cause respiratory depression.

Regional Anesthesia - Lumbar Epidural Block. - Spinal Anesthesia. - Caudal Block. - Paracervical Block. - Pudendal Nerve Block.