Επισκληρίδιος και τοκετός, μια τεκμηριωμένη ανάλυση

Posted by Αλ. Καλογερόπουλος on 01.02.2013

Λίγα λόγια για την επισκληρίδιο καθώς τόσα χρόνια μετά την καθιέρωση της στο χώρο της μαιευτικής αναλγησίας, με τεκμηριωμένη ασφάλεια και αποτελεσματικότητα, παραμένει άγνωστη ως μέθοδος και αντιμετωπίζεται με καχυποψία. Παρουσιάζω τα κύρια σημεία στα ελληνικά συνοδεύοντας τα με επιστημονική τεκμηρίωση στα αγγλικά από πρόσφατα άρθρα της ιατρικής βιβλιογραφίας με κυριότερο ένα άριστο review δημοσιευμένο στο  Medscape Reference: Labor and Delivery, Analgesia, Regional and Local Author: Hemant K Satpathy, MD; Chief Editor: Alex Macario, MD, MBA/ Updated: May 9, 2011, στην ιστοσελίδα: http://emedicine.medscape.com/article/149337-overview#a01 

 

Περιγράφω όλα τα πλεονεκτήματα αλλά και όλες τις επιπλοκές, ακόμα και τις πλέον σπάνιες.

Η επισκληρίδιος είναι η αποτελεσματικότερη μέθοδος αναλγησίας στον τοκετό.

 

 Epidural analgesia is the most effective form of pain relief in labor^{[16, 17, 18, 19, 20, 21]} and is used by most laboring women in United States.^[22]

 

Η επισκληρίδιος δεν αυξάνει την πιθανότητα καισαρικής.

  The rate of cesarean delivery remains unchanged.^[51]

 

 Δεν βλάπτει το μωρό, αντιθέτως σε συνθήκες επείγουσας καισαρικής του κάνει καλό.

  Infant outcome: No difference is observed in 5-minute Apgar score < 7.  No difference is observed in cord blood pH level.

Besides providing analgesia in labor, regional analgesia may facilitate atraumatic vaginal delivery of twins, preterm neonates, and neonates with breech presentation. General Anesthesia Increases Adverse Outcomes in Urgent Cesarean Delivery CME News Author: Ricki Lewis, PhD CME Author: Laurie Barclay, MD CME Released: 07/05/2012; Valid for credit through 07/05/2013

Babies exposed to GA during urgent delivery by cesarean delivery are more likely to experience adverse outcomes than those exposed only to RA, according to a study published online June 8 in the Australian and New Zealand Journal of Obstetrics and Gynaecology.

 Past studies have indicated that RA is safer for the mother than GA, but anesthesiologists must consider the benefit of GA in shortening labor, the authors write. This study indicates that RA is associated with better outcomes for the neonate, and therefore may be less risky than GA for this reason.

 

Μπορεί να προκαλέσει παροδική υπόταση στη έγκυο.

 Cardiovascular toxicity may include hypertension, tachycardia, cardiac arrhythmia, cardiac arrest, or (commonly) hypotension.

Hypotension, a common complication, develops soon after injection of local anesthetics. Because of the speed of the onset of regional block, it is seen more often with spinal block (25-67%) than with epidural block (8.5-9% in women with prior hydration or fluid bolus; 28-31% in women without prehydration).^{[21, 31, 32, 33, 34]} In patients with diminished intravascular volume (eg, preeclampsia, antepartum bleeding, dehydration) regional block is more highly associated with hypotension. Use of opioids alone usually does not produce hypotension. Recent use of ultra low dose of local anesthetics has lowered the incidence of hypotension.^[35]

 

Βοηθάει την αιμοδυναμική ισορροπία της εγκύου με προεκλαμψία ή άλλες ιατρικές επιπλοκές.

  It also helps control blood pressure in women with preeclampsia by alleviating labor pain, and it blunts the hemodynamic effects of uterine contractions and the associated pain response in patients with other medical complications.

 

Μπορεί να γίνει νωρίς στον τοκετό χωρίς αυτό να επηρεάσει την εξέλιξη του.

  Delaying the administration of epidural analgesia until labor is well established is reasonable. However, withholding analgesia until the patient has achieved an arbitrary cervical dilatation during the first stage of labor is unnecessary. In fact, timing of epidural placement has no effect on cesarean rate, fetal malposition, or forceps delivery.^{[27, 28]}

 

Ο παροδικός πονοκέφαλος μετά την επισκληρίδιο είναι η πιο συνηθισμένη επιπλοκή, σε ποσοστό 2-3%.

  Postdural puncture headache (PDPH) most likely results from cerebral vasodilatation or from the traction of cranial structures due to leakage of cerebrospinal fluid from the site of dural puncture. It occurs with similar frequency with each method of analgesia (spinal block, 1.5-3%; epidural block, 2%; combined spinal/epidural [CSE], 1-2.8%).

 

Μπορεί να προκαλέσει παροδική κατακράτηση ούρων και επίσχεση.

  Urinary retention during labor is not uncommon, but it appears to be more likely with regional analgesia.^[58] Patients in labor and postpartum should be observed for possible bladder distension, particularly when associated with suprapubic pain during uterine contraction. Urinary retention during labor is treated with catheterization

 

Ο παροδικός πυρετός αποτελεί μια επίσης επιπλοκή της επισκληριδίου. 

Fever, in association with epidurals,^{[53, 54]}is seen more often in nulliparous women (19% of nulliparous women, 1% of multiparous women).^[55] The incidence is nearly 24% per some studies.^[55] The odds ratio of fever incidence is 5.6. The association of fever with epidural analgesia is complex. Some authors attribute it to placental infection, whereas others believe it to be noninfectious. Both randomized and observational studies have demonstrated that the neonates of women who received epidural analgesia are more likely to be evaluated and treated with antibiotics because of concern about infection.^[56] From Medscape Education Clinical Briefs   Epidural Anesthesia Does Not Increase Maternal Temperature During Labor CME News Author: Lara C. Pullen, PhD

 

Ο κνησμός, η ναυτία και ο εμετός είναι επίσης επιπλοκές της επισκληριδίου.

• Pruritus is a commonly seen with regional opioid administration. It is more likely to occur with spinal or CSE block (41-85%) than with epidural block alone (1.3-26%).The etiology appears to be modulation of nociceptive reception, not histamine release. Thus, treatment with antihistamines such as diphenhydramine is not indicated, although antihistamines are often used for soporific effects.
• Nausea and vomiting occur commonly in laboring patients as an accompaniment of visceral pain. Neuroaxial analgesia block effectively diminishes or eliminates this visceral pain but can also precipitate nausea and vomiting. The mechanism is a decrease in blood pressure affecting the area postrema in the medulla or the cephalad spread of opioids to chemoreceptor trigger zone.

 Η επισκληρίδιος κατά την τοποθέτηση, μπορεί να προκαλέσει παροδική βραδυκαρδία στο έμβρυο. 

Fetal bradycardia occurs in 8% of cases.  Fetal bradycardia after induction of regional analgesia may result from decreased cardiac output, decreased uterine perfusion, or uterine tetany caused by maternal hypotension.^[52] 

 

Προοπτικές μελέτες δείχνουν ότι η επισκληρίδιος δεν αυξάνει την πιθανότητα για χρόνιο πόνο στη μέση 

Chronic back pain has been shown to be associated with epidural analgesia in retrospective studies.^[41] On the contrary, prospective cohort studies and one small, randomized controlled trial have found no significant association.^{[42, 43, 44, 45, 46, 47, 48]} Local tenderness at the site of epidural or spinal placement and transient backache are relatively common, particularly if placement of the block was difficult. This usually clears within several days to 3 weeks and may be related to superficial irritation of the skin or periosteal irritation or damage.  Postpartum backache may also be related to hormonal changes, softening of maternal ligaments, and mechanical changes (eg, exaggerated lumber lordosis, maternal weight gain). Although short-term back pain is common, it does not appear to be related to the use of regional analgesia. Similarly, no causal relationship exists between the use of epidural analgesia and the development of long-term postpartum backache. 

 

Η επισκληρίδιος καθυστερεί κατά 30 λεπτά το πρώτο στάδιο (μέχρι την τελεία διαστολή) και κατά 15 λεπτά το δεύτερο στάδιο του τοκετού, αυξάνοντας έτσι σε μικρό βαθμό την πιθανότητα χρήσης εμβρυουλκίας. 

 Labor is slightly prolonged with epidural analgesia.^{[16, 21, 49, 50]}The first stage is prolonged by nearly 30 minutes, and the second stage by 15 minutes. The prolongation of the second stage of labor increases the need for instrumental delivery (odds ratio [OR], 2.1).^[51]However, the reason for this increase with epidural remains unexplained. The most likely explanations include motor blockade preventing the mother from pushing, a lower threshold for instrumental delivery, and an association of higher frequency of persistent occipitoposterior presentation^[2] The rate of cesarean delivery remains unchanged.^[51] 

 

Η επισκληρίδιος δεν επηρεάζει αρνητικά τη γαλακτοφορία και το θηλασμό. 

• Breastfeeding success does not depend on the use of regional analgesia.^{[3, 57]}

Μπορεί να προκαλέσει συμπτώματα από το Κεντρικό Νευρικό Σύστημα, όπως ζάλη, εμβοές, μεταλλική γεύση, μούδιασμα της γλώσσας και του στόματος, ψευδή ομιλία, παράξενη συμπεριφορά, διέγερση, απώλεια συνείδησης, ευτυχώς σπανιότατα και παροδικά.

• Central nervous system toxicity may include dizziness, tinnitus, metallic taste, numbness of tongue and mouth, slurred speech, bizarre behavior, muscle fasciculation and excitation, convulsion, or loss of consciousness.

Μπορεί να αποτύχει σαν μέθοδος και η επίτοκος να συνεχίζει να πονάει σε ποσοστό 2-5%. 

 Inadequate or failed block happens more often with epidural than spinal block. The failure rate is as high as 2-5%. In 10-15% of cases, the pain relief is incomplete.^[59] The high failure rate may be related to the inexperience of practitioners or rapid progression of labor.

Μπορεί επίσης να προκαλέσει αναλγησία σε μεγαλύτερη έκταση, βάθος και διάρκεια και το μούδιασμα να αργήσει να υποχωρήσει. 

 Dense or prolonged epidural block can occur rarely after long continuous infusions or repeated bolus dosing. Τhe increasing use of dilute local anesthetics has decreased the incidence of prolonged or dense block. The resulting significant motor blockade can be bothersome to the patient and the nursing staff. This may also make the voluntary maternal expulsive efforts more difficult during the second stage of labor and lead to prolonged epidural blocks in the postpartum period, particularly if epinephrine is added to the anesthetic solution.