LABOR ANALGESIA: AN UPDATE

1. بسم الله الرحمن الرحيم LABOR ANALGESIA: AN UPDATE DR. FATMA AL DAMMAS CONSULTANT OBSTETRIC ANAESTHESIA AND PAIN DEPARTMENT OF ANAESTHSIOLOGY KING KHALID UNIVERSITY HOSPITAL RIYADH.

2. LABOR ANALGESIA: AN UPDATE IS THERE AN ADVANTAGE OF CSE OVER EPIDURAL? DR. FATMA AL DAMMAS CONSULTANT OBSTETRIC ANAESTHESIA AND PAIN DEPARTMENT OF ANAESTHSIOLOGY KING KHALID UNIVERSITY HOSPITAL RIYADH.

3. FROM THE HOLY QURAN IN THE NAME OF ALLAH THE MOST BENEFICIENT THE MOST MERCIFUL “AND THE PAINS OF CHILDBIRTH DROVE HER TO THE TRUNK OF A DATE PALM. SHE SAID “ WOULD THAT I HAD DIED BEFORE THIS, AND HAD BEEN FORGOTTEN AND OUT OF SIGHT”. SURAH 19: 23 (SURAH MARYAM)

4. CONTENTS • Introduction • CSE • Epidural analgesia • Review articles

5. INTRODUCTION

6. Stages of Labour

7. Pain pathways during labor

8. INTRODUCTION • There are many different techniques, both regional and non-regional to provide labour analgesia. • Non-regional techniques are the most frequently employed methods for labour analgesia. • Meperidine (pethidine) is the most frequently used opioid for labour analgesia. Its limited efficacy and side effects are well documented.

9. INTRODUCTION • Inhalation of nitrous oxide relieves labour pain to a significant degree . • Epidural analgesia, CSA , PCEA ,when compared with other methods, provides superior analgesia for labour.

10. IDEALLabour Analgesia • Safe (mother, fetus) • Composure, Control (Pain, Pain Relief) • Ease of Administration • Rapid, Profound, Consistent Analgesia (Stage I & II) • No Effect: Ambulation Maternal Expulsive Efforts Progress of Labour • Facilitate Surgical Anesthesia avoiding GA

11. CSE ADVANTAGES • Rapid Onset IT Component • Better Blocks • IT Medications Devoid of Motor Blockade “Walking Epidural” • Atraumatic Spinal Needles (fewer PDPH?). • Epidural Catheter for Supplemental Analgesia. • Epidural Catheter for Surgical Anesthesia.

12. CSE ADVANTAGES • Rapid Onset IT Component • Better Blocks • IT Medications Devoid of Motor Blockade “Walking Epidural” • Atraumatic Spinal Needles (fewer PDPH?). • Epidural Catheter for Supplemental Analgesia. • Epidural Catheter for Surgical Anesthesia.

13. Rapid Onset of Analgesia • Most dramatic feature; analgesia is often nearly complete before the epidural cath. is taped up and the tray discarded

14. Rapid Onset of Analgesia • Van de Velde randomized 110 parturients to epid. BUP 0.125% w sufentanil and epinephrine or IT sufentanil. • The time to effective analgesia was significantly shorter in the CSE group. • Van de Velde M: CSA in labor. Anesthesiology 2000 ;92:869-70

15. Rapid Onset of Analgesia • Nickells randomized women to epid. or SA BUP and fentanyl. The time to first painless contraction was shorter in the CSE group ( 10 ± 5.7 vs. 12.1 ± 6.5min) • Hepner randomized women to receive 10ml of 0.0625% BUP + fentanyl 2mcg/ml + epinephrine + bicarbonate epidurally or 25mcg fentanyl and 2.5mg BUP IT • 26/26 patients had a VAS < 3 within 5min in CSE group, only 17/24 in the epidural group

16. Does a few minutes advantage in analgesic onset matter?

17. CSE ADVANTAGES • Rapid Onset IT Component • Better Blocks • IT Medications Devoid of Motor Blockade “Walking Epidural” • Atraumatic Spinal Needles (fewer PDPH?). • Epidural Catheter for Supplemental Analgesia. • Epidural Catheter for Surgical Anesthesia.

18. Better Blocks • Quality of analgesia is improved by CSE • Norris retrospectively compared epid. and CSE techniques in 1661 women who received either technique and found a lower incidence of failed blocks and a greater incidence of bilateral symmetrical analgesia w CSE. • Norris MC .Anesth Analg 1995;79:529-37

19. Better Blocks • CSE cannot be obtained using the needle-through-needle technique unless the epid needle is positioned near the mid line of the actual epid space. • There may be passage of LA from the epidural space into the IT space via the dural hole. • There may be synergism between epid and spinal blocks, such that one enhances the other.

20. CSE ADVANTAGES • Rapid Onset IT Component • Better Blocks • IT Medications Devoid of Motor Blockade “Walking Epidural” • Atraumatic Spinal Needles (fewer PDPH?). • Epidural Catheter for Supplemental Analgesia. • Epidural Catheter for Surgical Anesthesia.

21. Less Motor Block • CSE associated with less total LA use for a given degree of analgesia • In a randomized trial, Collis found 12/98 patients in the CSE group, compared to 32/99 in the epid group had leg weakness at 20min. • Requirements for anesthesiologist intervention are lower w CSE regardless of technique. • Collis RE. Davies DWL. Aveling W. Randomised comparison of CSE and standard epidural in labour Lancet 1995, 345.4 3-6.

22. Protocol for Ambulation • • A patient must remain at bed rest for at least 30 minutes following initiation of CSE. • • Prior to ambulation, approval must be obtained from the labor nurse, obstetrician, and anesthesiologist. FHR tracing must be within normal limits prior to ambulation. • • Ambulation is allowed only after the patient has been examined by the anesthesiologist to rule out motor block. • • A BP measurement taken immediately prior to ambulation while the patient is upright.

23. Protocol for Ambulation • • Ambulating parturients must be supported on one side by a companion and by an iv pole (with wheels) for support on their other side. • • If a parturient does not wish to ambulate but wants to get out of bed, (or for patients who need to have continuous FHR monitoring), they may be assisted out of bed into the rocking chair adjacent to the bed.

24. Less Motor Block • Adding opioids < MB • “Walking” epidurals: < MB meant better outcomes • No evidence of improved labor pattern/outcome with ambulation !!!. • Women don’t walk even if they can. • Monitoring problems. • Techniques that allow “walking” may be “better” whether or not patient ambulates.

25. Intrathecal Bupivacaine and Sufentanil for Ambulatory Labor Analgesia: Effect of Dose ReductionsSchultz R, Campbell DC, et al. Anesth’logy (SOAP suppl) A18, 1998 VAS PAIN * * * P < 0.05 * * * Time (min)

26. Does a Walking” epidurals meant better in analgesic outcomes?

27. CSE ADVANTAGES • Rapid Onset IT Component • Better Blocks • IT Medications Devoid of Motor Blockade “Walking Epidural” • Atraumatic Spinal Needles (fewer PDPH?). • Epidural Catheter for Supplemental Analgesia. • Epidural Catheter for Surgical Anesthesia.

28. CSE ADVANTAGES PDPH • Rate ~ 1% • CSE technique might actually decrease the incidence of dural puncture with the epid needle by allowing the anesthesiologist to confirm an equivocal loss of resistance by passage of a pencil point spinal needle rather than advancing the large bore epid needle further.

29. CSE ADVANTAGES • The use of small bore “atraumatic” spinal needles will reduce the incidence of PDPH in patients receiving CSE . • Possible explanation for this finding is that, the spinal needle may be used for verification of correct placement of the epidural needle when there is inconclusive loss of resistance David J. Birnbach MD ;Advances in labour analgesia . CAN J ANESTH 2004 51: 6

30. ↓ PDPH has advantage over analgesia ?

31. CSE ADVANTAGES • Rapid Onset IT Component • IT Medications Devoid of Motor Blockade “Walking Epidural” • Atraumatic Spinal Needles (fewer PDPH?). • Epidural Catheter for Supplemental Analgesia. • Epidural Catheter for Surgical Anesthesia.

32. Better Patient Satisfaction An Updated Report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia Anesthesiology 2007; 106:843–63 • Several studies have found better patient satisfaction scores with CSE vs. conventional epid. • Others have found no difference, but none have found better satisfaction with conventional epid analgesia

33. Better in Difficult Backs • An Updated Report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia Anesthesiology 2007; 106:843–63 • CSE has been associated with improved chances of adequate analgesia in parturients with scoliosis or other causes of a difficult back.

34. Progress of Labor • Studies have compared obstetric outcomes associated with CSE and epidural labor analgesia. • Tsen et al. reported faster initial cervical dilation and shorter time from induction of analgesia to full cervical dilation among women receiving CSE analgesia vs epidural analgesia. • Tsen L.C,Thue BDatta S: Anesthesiology 2001;91;920-5

35. Progress of Labor • Tow large randomized trials have confirmed an increase in the spontaneous vaginal delivery rate with CSE vs. conventional epid analgesia.

36. Progress of Labor • The pain relief leads to a decrease in the output of the sympathetic nervous system. There is a significant decrease in the level of circulating epinephrine after the induction of labour analgesia. • Epinephrine is a tocolytic. • A decrease in epinephrine will cause an increase in uterine tone P. D. W. Fettes, C. S. Moore1 analgesia during labour British Journal of Anaesthesia July 18, 2006 97 (3): 359–64

37. Other advantage • A retrospective analysis involving near 20,000 patients found incidences of overall failure, IV epid cath, wet tap, inadequate epid analgesia and cath replacement were all lower in patients receiving CSE. • Sacral analgesia is difficult to obtain with conventional epidural, CSE is good at providing it. • CSE is an obvious choice in advanced labor.

38. Do a few advantages in CSE analgesia matter?

39. CSEComplications • Fetal bradycardia/FHR changes • Pruritus • Infection • Neurotrauma • Other side effects

40. Fetal Heart Rate

41. Post-CSE NRFHR: FETAL BRADYCARDIA • 1993 Cohen Anesth Analg15% (11/73) • 1994 Clark Anesth’logy 30% (9/30) • 1997 Campbell DC Anesth’logy15% (6/39) • 1998 Gambling Anesth’logy18% (72/400) • 1999 Palmer Anesth Analg12% (12/100) * • 2000 Wong Anesth’logy 17% (28/67) • 2001 Van de Velde Reg An Pain Man11% (40/351) * * 50% greater than Epidural

42. How does labour analgesia cause fetal bradycardia?

43. FETAL BRADYCARDIA 1. The pain relief leads to a decrease in the output of the sympathetic nervous system. There is a significant decrease in the level of circulating epinephrine after the induction of labour analgesia. 2. Epinephrine is a tocolytic. A decrease in epinephrine will cause an increase in uterine tone. 3. Increased uterine tone will decrease placental blood flow. 4. If placental blood flow is decreased significantly there will be a subsequent fetal bradycardia. • Edward T. Riley MDCAN J ANESTH 2003 / 50: 6 / pp R1–R3

44. FETAL BRADYCARDIA 1. Pain relief leads to a decrease in blood pressure. 2. The decrease in blood pressure, norepinephrine levels increase. 3. This will lead to uterine artery constriction. 4. Uterine artery vasoconstriction will decrease placental blood flow. 5. If placental blood flow is decreased significantly there will be a subsequent fetal bradycardia. Edward T. Riley MDCAN J ANESTH 2003 / 50: 6 / pp R1–R3

45. FETAL BRADYCARDIA Rapid onset pain relief may cause temporary norepinephrine predominance • Norepinephrine • - effects uterine tonus  uterine contractions  Epinephrine - effects uterine tonus  uterine contractions 

46. FETAL BRADYCARDIA Several studies found no increased incidence of fetal heart rate abnormalities or increased Caesarean section rate ~ CSE* * Nielsen PE et al. Anesth Analg 1996; 83:742-746 Albright GA et al. Reg Anesth 1997; 22:400-405 Eberle RL et al. Am J Obstet Gynecol 1998; 179:155-159 Palmer CM et al. Anesth Analg 1999; 88:577-581 Norris MC et al. Anesthesiology 2001; 95:913-920

47. CSEComplications • Fetal bradycardia/FHR changes • Pruritus • Infection • Neurotrauma • Other side effects

48. Norris MC, et al. Anesth Analg 79:529-37, 1994 Complications of Labor Analgesia: Epidural versus Combined Spinal Epidural Techniques LEA (n=388)CSE (n=536) Pruritus 1.3 % 41.3 %

49. CSEComplications • Fetal bradycardia/FHR changes • Pruritus • Infection • Neurotrauma • Other side effects

50. Infection • There are least 8 case reports of spinal meningitis related to a CSE. • Too many instrumentations- Too many cooks spoil a broth? • There is also a case report of epid abscess after a CSE for labor. • Conversely spinal anesthesia for elective CS does not carry these risks.