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Child Birth: “Pain or Pleasure?”
Ketan Parikh
Introduction
Labour pain is described as the worst pain
ever felt by a human being in their entire life. Even the newborn cries out aloud for the labouring mother knowing very well what she has gone through! In this day and age, why are we ignoring the cry for pain relief? Is it, because we are still holding on to the concept of “No pain…No gain?”
Labour pain is mainly due to stretching and tearing of uterine muscle fibres and dilatation of cervix that occur during each contraction. There is no evidence what so ever that pain in labour is beneficial to either mother or foetus. On the other hand, its deleterious effects are considerable. In mother it leads to increased oxygen consumption leading to oxygen debt, uterine vasoconstriction leading to reduced placental circulation, increased sympathetic stimulation leading to dysfunctional labour and loss of morals with unpleasant memories. In the foetus it causes foetal hypoxia and acidosis. Mind you, these are the changes occurring during labour in normal pregnancy. These effects could be much more significant and dangerous in high risk pregnancies. Is pain really useful?
Pain relief in labour got its Royal Chartered in 1842, when Queen Victoria, requested for pain relief during labour and delivery of her eighth child, Prince Leopard. Since then, various methods have been described and practiced to relieve pain of the labouring mothers. Today, options available are Non-pharmacological as well as pharmacological where various medicines can be given either systemically or locally. All these methods have been used with limited success. They are useful only during the latent phase or in early labour. These methods are unpredictable and inconsistent.
Epidural Analgesia for Labour
Epidural is the best and the safest method available as it actually abolishes pain, is most reliable and effective, and it causes neither sedation nor any maternal or foetal depression. It prevents hyperventilation, reduces hypoxia, prevents cardiovascular changes, reduces work of labour, maternal metabolism and O2 consumption is reduced and maternal and foetal acidosis is prevented. Epidural improves generalized well being of both mother and the foetus. It gives an awake, comfortable, and cooperative patient with active participation in childbirth.
Indications
a) Maternal Indications:
1. The main indication is unbearable labour pain.
2. Patients with PIH, pre-eclampsia or eclampsia, and cardiac disease do better as epidural will prevent deleterious effects on cardiovascular system by preventing increase in HR, BP and cardiac output. In indicated cases, by blocking the urge to push and allowing painless forceps delivery epidural can prevent acute cardiovascular stress of the Valsalva manoeuvre.
3. Patients with Respiratory disease like Asthma or emphysematous bulla will also benefit from this form of pain relief without undue sedation associated with narcotics.
4. In extremely anxious patient, by relaxing the patient, epidural prevents dysfunctional labour and hastens the cervical dilatation.
b) Foetal Indications
1. In cases of pre-maturity and IUGR, epidural improves intervillous blood flow and provides analgesia without any hypoxia or undue sedation.
2. If vaginal delivery is planned for breech presentation or Twin pregnancy, epidural is very useful. In breech presentation, inadequate or no pain relief may result in premature pushing efforts with potential risk of prolapsed cord or head entrapment with incomplete cervical dilatation. With epidural the pushing urge can be controlled. During vaginal delivery of twins, if internal pudalic version is needed for the second twin, it can be done under epidural without any risk of hypoxia or sedation to the baby.
3. Within minutes epidural analgesia can be effectively converted to epidural anaesthesia if an emergency caesarian section is necessary.
c) Labour Indications
1. In dysfunctional labour, leading to hypertonic uterine contraction and cervical dystocia, when spiraling pain is relieved by epidural, the normal pattern of uterine activity and cervical dilatation resumes.
2. During trial of labour, epidural block is always useful just in case a need for emergency LSCS arises.
3. Same condition applies to Trial of Scars for normal vaginal delivery. The scar may be of previous LSCS or myomectomy or repair of a malformed uterus
The absolute contraindication is patient refusal. Epidural is contraindicated in cases of allergy to local anaesthetics, local sepsis and clotting disorders. Previous LSCS is NOT a contraindication for epidural pain relief if vaginal delivery is planned.
If epidural is so good what are we worried about? Are we exposing the mother or foetus to any undue risks? Let’s look at effects of epidural on Progress of labour, Mode of delivery sand Mother and Neonate.
A) Effect of Epidural on progress of labour
1st Stage : Epidural does not prolong the first stage of labour.
In fact in cases of dysfunctional labour or in extremely anxious patient, it may hasten this stage by rapid cervical dilatation. Elevated catecholamines, particularly epinephrine that increases several folds during labour due to anxiety, pain or stress, are potentially tocolytic. Regional analgesia modifies this pattern by reducing epinephrine but not norepinephrine. Studies have shown that reduction in epinephrine, with continued presence of norepinephrine, can lead to substantial increase in uterine contractility.
2nd Stage : It may seem that the second stage is prolonged but an enduring obstetrician and well motivated patient will deliver vaginally without instrumentation.
3rd Stage : Epidural is useful in suturing episiotomies or tears. If manual removal is necessary for retained placenta, epidural is very useful
B) Effect of Epidural on mode of delivery
The main concern of every obstetricians and obstetric anaesthesiologists is-does epidural pain relief during labour increase the rate of operative delivery? Epidural may block the bearing down effect and reduces maternal urge to push during second stage. This problem is well understood and epidural technique is refined to its tune. The new concept is to use lower concentration of local anaesthetics with minimal amount of opioids, which will only block the pain and touch fibres leaving proprioceptive and motor fibres unblocked. This is what is called a walking epidural or mobile epidural as there is only sensory block relieving the pain but the motor power is retained giving full mobility to the patient. This allows the patient to get the urge to push and participate in active child birth.
A study from University of Munich, Germany, where the obstetric practice was observed from 1979 to 1996, concluded that the overall rate of operative deliveries does not increase despite a marked increase in the utilization of epidural pain relief. On the contrary, they projected epidural analgesia may improve an otherwise dysfunctional labour pattern and thus save a selected group of patients from undergoing Caesarean Section.
Various studies have failed to establish epidural as the only cause for instrumental vaginal delivery. There are many factors that play part in using a vacuum or outlet forceps. Epidural may be more of an associative factor than a causative factor.
C) Effect of Epidural on mothers
The problems on the mother are two fold, Short term and Long term.
A) Short term
1. The most dreadful problem is inability to relieve pain, failed epidural or inadequate pain relief.
2. Hypotension, shivering, urinary retention and mild motor block limiting patient’s mobility are common and benign side effects.
B) Long term
1. Accidental Dural Puncture can occur in the best of the hands leading to Post Dural Puncture Headache. Better technique and more experience reduces the incidence to almost < 0.1% i.e. 1 or less in 1000 epidurals
2. A few retrospective studies associated epidurals with increased risk of long term backache. Extensive prospective work by Prof. Reynolds and her group at St Thomas’ Hospital, London have disputed these results and categorically ruled out any association between the two. The overall incidence is no more than in general population
3. Neurological damages are extremely rare, mostly of obstetric cause and usually resolve within 6-8 weeks.
D) Effect of Epidural on Neonate
There is no evidence of any significant neonatal drug accumulation or any adverse effect even after prolonged use of epidural infusion. The epidural pain relief improves neonatal oxygenation and reduces the risk of foetal acidosis.
Conclusion
Giving birth has always been one of the memorable, most pleasurable as well as most painful experience of a woman’s life. By providing them the effective pain relief, one can make sure they remember the Pleasure and not the pain.
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