1. Pain Relief in Labor

2. Learning Objectives
Understand when and how to use various pain relief strategies
Understand importance of pain relief strategies in aiding the progression of labor and promoting maternal well being
Understand pharmacological and non pharmacological ways to manage pain

3. “Almost all women experience pain during labor but the response of individual women to labor pain is widely different”
– from WHO website

4. Definitions
Pain
Unpleasant sensory and emotional experience associated with actual or potential tissue damage
It is important to determine how a woman is coping and what her desires and fears are during labor.
Relieving suffering and pain are themselves worthy goals to strive for
Not all women in labor need medications. It is important to assess how she is doing and coping.

5. Adverse consequences to labor pain
Produces physiological changes in addition to emotional distress
Hyperventilation
Maternal alkalosis that impairs O2 transfer to fetus
Utero / Placental vasoconstriction
Affect placental perfusion
Psychological effects
Maternal anxiety and pain increase the dysfunction of labor
1.Shifting the oxygen hemoglobin disociation curve to the Left increasing oxygen’s affinity to maternal Hb
2.Also causes ureto/placental vasocontriction

6. Adequate pain relief in labor
Decreases maternal anxiety
Shortens labor
Decreases the need for intervention
Makes labor a more positive experience

7. Support Maternal anxiety and pain increase the dysfunction of labor
Physiologic discomforts add to labor pain and therefore should be addressed
Anxiety and fear should be reduced by providing information and support

8. Support Companions Shortens labor
Decreases the need for pain medications
Decreases interventions including operative vaginal delivery and C-section

9. Types of Non-pharmacological Pain Management
Decrease painful stimuli
Stimulate peripheral receptors
Increase descending inhibitory pathways on pain receptors

10. Decrease Painful Stimuli
Maternal movement and position change to enhance comfort
Counter pressure on a woman’s sacrum

11. Stimulate Peripheral Sensory Pathways
Massage
Water immersion
Aromatherapy
Superficial heat or cold packs
Accupuncture or accupressure

12. Increase pain inhibitory pathways
Distraction and focusing techniques
Audio relaxation

13. Systemic Pharmacological methods
Nitric Oxide
Inhaled
Self administered for the duration of contraction
Good for transition phase (late active phase) or short procedures
Quick on quick off with low side effect profile

14. Systemic Pharmacologic Methods
Narcotics ( ie. Morphine)
Given IM / IV
Can be given early in labor
Side effects:
respiratory depression in baby if given close to delivery (This is easily reversed with Naloxone)
variations in fetal heart rate

15. Local pharmacological techniques
Pudendal block
Peripheral nerve block
Low systemic effects
Use Lignocaine (use 30 ml of 0.5% for block and then can still use 10ml into perineum for repair)
Useful in second stage labour, especially prior to any vaginal instrumentation for delivery
Anaesthetize early enough to provide sufficient time for effect
You are trying to anaesthetize the pudendal nerve as it passes through the lesser sciatic notch
2 approaches: through vagina or perineum

16. Local pharmacological techniques
Pudendal block: Vaginal Approach
Use Lt index finger to palpate woman’s left ischial spine through vagina
Advance needle towards the left ischial spine by placing the needle tip just beyond your fingertip to guide it to proper position
Be careful not to get needle-stick injury
Advance needle through vaginal mucosa until it pierces sacrospinous ligament
Always aspirate before injecting to be sure you are not in a vessel…. If you aspirate blood, DO NOT INJECT because IV lignocaine can cause death
Inject approx 15 ml on each side

17. Local pharmacological techniques
Pudendal block: Perineal Approach
Place two fingers in vagina to guide needle through perineal tissue to tip of woman’s ischial spine
Inject approximately 15 ml on either side of 0.5% lignocaine

18. Local pharmacological techniques
Perineal infiltration
Perineal skin infiltration
Infiltration of local anesthetic (lignocaine)
Useful in instrumental vaginal delivery, episiotomy and in repair of a perineal laceration

19. Regional anesthesia Epidural Little systemic effects on baby
Can provide pain relief throughout entire labor and delivery
Associated with longer 1st and 2nd stages of labor, oxytocin augmentation, malpositions and instrumental vaginal delivery
Do not stop epidural in 2nd stage and allow for longer 2nd stage before intervening.