To walk or not to walk, is that the question?The initial development of neuraxial labour analgesia in the early 20th century, through spinal, caudal and later epidural administration, did not really result in major application until the sixties and seventies. It took the development of epidural catheters and novel Local Anesthetics (LA) for widespread adaptation of epidural labour analgesia in many countries. Initially high concentrations of LA were used, which provided prolonged analgesia but also resulted in profound motor blocks. These dense blocks were at first considered to be an advantage as they could easily be extended in to surgical anesthesia for Cesarean Delivery (CD). But eventually different epidural mixtures were developed, with lower concentrations LA and adjuvant use of opioids and other drugs, in order to achieve similar and improved analgesia without the unwanted side effects and safety risks related to high concentrations LA. With the introduction of improved spinal needle design and size, a spinal component was added to the epidural technique in order to optimize analgesia further. the Combined-Spinal Epidural (CSE) with its fast onset, excellent analgesia and minimal motor block made Morgan introduce in 1995 the term ‘walking epidural’.¹ the parturient was no longer confined to bed, and up to 85% of women could stand and walk around while in labour, either using CSE or conventional epidurals with low concentration LA.² In recent years better techniques have been developed to replace the continuous epidural provision of analgesia and improve the spread of LA by bolus injections. Both Patient Controlled Epidural Analgesia (PCEA) and Programmed Intermittent Epidural Bolus (PIEB) improved epidural spread of drugs and further reduced the total dose of LA, with even less motor blockade and optimal ambulation for parturients.^{3 4} While using the term ‘walking epidural’, three main questions regarding the woman in labour pop up.

(1) Could she walk?: Conventional epidural motor blocks prevented mobilization, increased instrumental delivery rates and caused urinary retention, all negatively influencing patient satisfaction. With the reduction of concentrations and total dose of LA, motor function appeared intact. In order to mobilize during neuraxial labour, lower extremity strength should be preserved, with the ability to perform partial knee bends while standing and without any somatosensory deterioration. It has been demonstrated that balance function is impaired in á terme pregnant women.^{5 6} And while initiation of low-dose neuraxial analgesia did not seem to decline balance, Wilson’s secondary analysis of the COMET study demonstrated a gradual reduction of lower limb motor power which occurred as time progressed during labour with neuraxial analgesia, even in the low dose epidural analgesia groups.⁷ This reduction has not been observed in other studies using low dose regimens, but often these observations were for a limited time period in relatively short labours while using varying motor block evaluation scores.^8–10 When observing the continuous epidural infusion of low dose LA for a more prolonged period, Capogna indeed reported motor block in 37% of patients, compared to 2.7% when PIEB with the same LA mixture was used.¹¹ It appears that not all ‘walking epidurals’ are the same, and thorough motor function evaluation is needed before the parturient is allowed to walk, supported, under well-defined circumstances.

(2) Should she walk? Advantages of walking and/or upright position of a labouring woman were presumed equal in parturients with or without neuraxial analgesia, as long as motor function was not reduced. In absence of neuraxial analgesia, walking and an upright position does indeed result in a reduced cesarean rate, shorter labour duration and improved fetal outcomes, but these differences have not been demonstrated while walking with a ‘walking epidural’.¹² the minimized motor block and not the ambulation persé seems to be responsible for the reduced instrumental delivery rate observed with low dose epidurals. the effect of mobilization on other obstetric and neonatal outcomes is not at all consistent.^13–15 These inconsistent results may be related to the actual time spent walking, as in most trials either limited time was spent walking, or women preferred not to walk at all, even with intact motor function.^{16 17} Walking during epidural analgesia is not harmful for mother and baby, but it does not reduce the duration of the first stage of labour, the need for augmentation or changes the mode of delivery.^{18 19} Walking is not without any benefit at all: it improves maternal satisfaction and outcome. a short walk to the bathroom during epidural analgesia significantly reduced residual bladder volume and the need for (undesirable) urinary bladder catheterization.²⁰ It contributes to a maternal sense of control, as does the freedom to move around and change position during labour, even if not walking.

(3) Would she walk? the often observed improved maternal satisfaction with low dose epidural techniques does not appear to be related to the ability to walk, as many women do not attempt to stand or walk during labour and/or walk less than anticipated, irrespective of the mode of analgesia. ²¹ Not so much the sort of analgesia determines ambulation, but patient and obstetric-related factors. Analgesia is often requested once labour intensity has become overwhelming and exhausting, and many women prefer to rest or sleep once pain has subsided.²² a prospective audit performed in a UK university hospital demonstrated that even if information on mobile epidurals was provided, only 14% of patients actually walked. the majority of women did not want to walk, experienced heavy legs or were hindered by too much monitoring or catheters.²³

‘One of the several aims of labour regional analgesia should be the retention of mobility even if walking is not desired or permitted’.¹ By optimizing neuraxial analgesia, mobilization will remain possible throughout labour. But it is not the epidural which walks, nor does it decide if a parturient will walk. the time has come to acknowledge woman’s autonomous decision and right to walk or not to walk during labour and finally discard the term ‘walking epidural’.

References

1. Morgan BM. ‘Walking’ epidurals in labour. Anaesthesia 1995;50:839–40.

2. Collis RE, Davies DWL, Aveling W. Randomised comparison of combined spinal-epidural and standard epidural analgesia in labour. Lancet 1995;345:1413–6.

3. Carvalho B, George RB, Cobb B, McKenzie C, Riley ET. Implementation of Programmed Intermittent Epidural Bolus for the Maintenance of Labor Analgesia. Anesth Analg 2016;123(4):965–971.

4. Halpern SH, Carvalho B. Patient-controlled epidural analgesia for labor. Anesth Analg 2009;108(3):921–8.

5. Davies J, Fernando R, Verma S, Found P, McLeod A. Postural Stability Following Regional Analgesia for Labor. Anesthesiology 2001;94(Supplement):1.

6. Pickering AE, Parry MG, Ousta B, Fernando R. Effect of combined spinal-epidural ambulatory labor analgesia on balance. Anesthesiology [Internet]. 1999 Aug [cited 2019 May 16];91(2):436–41.

7. Wilson MJA, MacArthur C, Cooper GM, Shennan A, COMET Study Group UK. Ambulation in labour and delivery mode: a randomised controlled trial of high-dose vs mobile epidural analgesia. Anaesthesia[Internet]. 2009 Mar [cited 2019 May 16];64(3):266–72.

8. Wong CA, Ratliff JT, Sullivan JT, Scavone BM, Toledo P, McCarthy RJ. A randomized comparison of programmed intermittent epidural bolus with continuous epidural infusion for labor analgesia. Anesth Analg 2006;102(3):904–9.

9. Chua SMH, Sia ATH. Automated intermittent epidural boluses improve analgesia induced by intrathecal fentanyl during labour. Can J Anaesth[Internet]. 2004;51(6):581–5.

10. Lim Y, Sia AT, Ocampo CE. Comparison of intrathecal levobupivacaine with and without fentanyl in combined spinal epidural for labor analgesia. Med Sci Monit [Internet]. 2004 Jul [cited 2018 Aug 29];10(7):PI87–91.

11. Capogna G, Camorcia M, Stirparo S, Farcomeni A. Programmed intermittent epidural bolus versus continuous epidural infusion for labor analgesia: the effects on maternal motor function and labor outcome. a randomized double-blind study in nulliparous women. Anesth Analg 2011;113(4):826–31.

12. Lawrence A, Lewis L, Hofmeyr GJ, Dowswell T, Styles C. Maternal positions and mobility during first stage labour. In: Lawrence A, editor. Cochrane Database of Systematic Reviews [Internet]. Chichester, UK: John Wiley & Sons, Ltd; 2009 [cited 2019 Apr 4].

13. Comparative Obstetric Mobile Epidural Trial (COMET) Study Group UK. Effect of low dose mobile versus traditional epidural techniques on mode of delivery: a randomised control trial. Lancet. 2001;358:19–23.

14. Sultan P, Murphy C, Halpern S, Carvalho B. the effect of low concentrations versus high concentrations of local anesthetics for labour analgesia on obstetric and anesthetic outcomes: a meta-analysis. Can J Anesth 2013;60(9):840–54.

15. Roberts CL, Algert CS, Olive E. Impact of first-stage ambulation on mode of delivery among women with epidural analgesia. Aust N Z J Obstet Gynaecol [Internet]. 2004 Dec [cited 2019 May 16];44(6):489–94.

16. Vallejo MC, Firestone LL, Mandell GL, Jaime F, Makishima S, Ramanathan S. Effect of epidural analgesia with ambulation on labor duration. Anesthesiology 2001;95(4):857–61.

17. Collis RE, Harding SA, Morgan BM. Effect of maternal ambulation on labour with low-dose combined spinal-epidural analgesia. Anaesthesia 1999;54(6):535–9.

18. Roberts CL, Algert CS, Oive E. Impact of first-stage ambulation on mode of delivery among women with epidural analgesia. Aust New Zeal J Obstet Gynaecol [Internet]. 2004 Dec [cited 2019 May 16];44(6):489–94.

19. Bloom SL, MCIntire DD, Kelly MA, Beimer HL, Burpo RH, Garcia MA, et al. Lack of effect of walking on labor and delivery. NEJM [Internet]. 1998 [cited 2019 Jun 10];339:76–9.

20. Weiniger CF, Yaghmour H, Nadjari M, Einav S, Elchalal U, Ginosar Y, et al. Walking reduces the post-void residual volume in parturients with epidural analgesia for labor: a randomized-controlled study. Acta Anaesthesiol Scand [Internet]. 2009 May [cited 2019 May 16];53(5):665–72.

21. Cooper GM, MacArthur C, Wilson MJA, Moore PAS, Shennan A. Satisfaction, control and pain relief: short- and long-term assessments in a randomised controlled trial of low-dose and traditional epidurals and a non-epidural comparison group. Int J Obstet Anesth [Internet]. 2010;19(1):31–7.

22. Breen TW, Shapiro T, Glass B, Foster-Payne D, Oriol NE. Epidural anesthesia for labor in an ambulatory patient. Anesth Analg 1993;77(5):919–24.

23. Dukoff-Gordon A, Fruggeri L, Roulson C. Do women with mobile epidurals actually mobilise? Reg Anesth Pain Med [Internet]. 2016;41(5 Supplement 1):e121.