II. Indication

  1. Analgesia and Anesthesia for First Stage of Labor
  2. Gives four hours of Labor Anesthesia

III. Mechanism

  1. Acts at Opioid receptors
    1. Substantia gelatinosa of dorsal horn
    2. Affects afferent visceral pain impulses only
  2. Contrast with Epidural Anesthesia
    1. ITM does not affect second stage somatic pain
    2. ITM does not interfere with maternal pushing
      1. Does not inhibit efferent muscular paths

IV. Labs

V. Advantages

  1. Single injection into the intrathecal space offers nearly immediate relief without retained catheter

VI. Technique

  1. Patient lying in lateral decubitus position or seated
  2. Spinal needle Insertion
    1. Site: L3-4 interspace
      1. Insertion must be below L1-2 to prevent spinal cord injury
    2. Needle Gauge: 25 gauge ("Pencil point")
      1. Decreases Incidence of Postdural Puncture Headache
    3. Enter the dural sac as in Lumbar Puncture
      1. Clear Cerebrospinal Fluid should return promptly
  3. Instill Intrathecal medications
    1. Hyperbaric Lidocaine 25-50 mg
    2. Additional agents
      1. Fentanyl (Duragesic) 10-25 mcg
      2. Morphine (preservative-free) 0.25 mg

VII. Monitoring

  1. Initial
    1. Blood Pressure, Pulse every 5 minutes for 30 minutes
    2. Respiratory Rate every 15 minutes for 1 hour
  2. Later
    1. Monitor hourly for 24 hours
  3. Naloxone by bedside for respiratory depression

VIII. Adverse Effects

  1. Maternal Hypotension
  2. Nausea or Vomiting
  3. Pruritus
  4. Skin Hypersensitivity
  5. Postdural Puncture Headache
  6. Associated with increased instrument-assisted Vaginal Delivery (vacuum or forceps)

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Ontology: Spinal Anesthesia (C0002928)

Definition (NCI) A procedure in which a pharmaceutical agent is administered into the subarachnoid space, producing a loss of sensation at and below the level of the block.
Definition (NCI_NCI-GLOSS) A temporary loss of feeling in the abdomen and/or the lower part of the body. Special drugs called anesthetics are injected into the fluid in the lower part of the spinal column to cause the loss of feeling. The patient stays awake during the procedure. It is a type of regional anesthesia.
Definition (CSP) interruption of the conduction of impulses in peripheral nerves or nerve trunks by the injection of a local anesthetic solution.
Concepts Therapeutic or Preventive Procedure (T061)
MSH D000775
SnomedCT 231249005, 180888008, 150864001, 61478003
English Anesthesia, Spinal, Anesthesias, Spinal, Spinal Anesthesias, Spinal Anesthesia, Spinal anaesthetic NOS, Spinal anesthetic NOS, Spinal anesthesia (all forms), LA intrathecal block, spinal anesthesia (treatment), spinal anesthesia, Spinal anaesthesia (all forms), Spinal anaesthesia, Local anesthetic intrathecal block, Local anaesthetic intrathecal block, Spinal anaesthetic, Spinal anesthetic, Spinal anesthesia, spinal anaesthesia, spinal anesthetic, Spinal Block, Spinal anesthetic NOS (procedure), Local anaesthetic intrathecal block (procedure), Spinal anesthesia (procedure), subarachnoid block, SAB, spinal block, Intrathecal block, Spinal block, Subarachnoid block, Intradural block, Local anesthetic intrathecal block (procedure)
Dutch spinale anesthesie (alle vormen), spinale anesthesie, Anesthesie, spinale, Spinale anesthesie
French Anesthésie rachidienne (toutes formes), Anesthésie spinale, Rachi-anesthésie, Rachianesthésie, Anesthésie rachidienne
German Spinalanaesthesie (alle Arten), Spinalanaesthesie, Anästhesie, Spinal-
Italian Anestesia spinale (ogni forma), Anestesia spinale
Portuguese Raquianestesia (todas as formas), Anestesia Espinal, Anestesia espinal, Raquianestesia
Spanish Anestesia espinal (todos los tipos), anestesia espinal, anestesia subaracnoidea, anestesia espinal, SAI (procedimiento), anestesia raquídea (procedimiento), anestesia espinal, SAI, anestesia raquídea, bloqueo con anestesia local intratecal (procedimiento), bloqueo con anestesia local intratecal, Anestesia espinal, Anestesia Raquidea
Japanese 脊髄麻酔, 脊髄麻酔(各種), セキズイマスイカクシュ, セキズイマスイ
Swedish Ryggbedövning
Czech anestézie spinální, anestézie subarachnoidální, Spinální anestezie, Spinální anestezie (všechy typy), Subarachnoidální anestezie
Finnish Spinaalipuudutus
Polish Znieczulenie rdzeniowe, Znieczulenie podpajęczynówkowe
Hungarian Spinal anaesthesia (minden forma), Spinal anaesthesia
Norwegian Ryggmargsbedøvelse, Regionalbedøvelse, Spinalanestesi, Spinalbedøvelse