Cesarean Section Should be Managed: Low Dose / CSE versus High Dose Spinals with Vasopressors

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Cesarean Section Should be Managed: Low Dose / CSE versus High Dose Spinals with Vasopressors Cristian Arzola MD MSc Department of Anesthesia and Pain Management Mount Sinai Hospital and University of Toronto 1

Surgical anesthesia pain/discomfort surgical conditions Side effects maternal fetal 2

CSE Low-dose Spinal High-dose Intrathecal dose reduce Hypotension Intrathecal dose Surgical Anesthesia Epidural catheter improves and prolongs surgical anaesthesia Vasopressors Prevent and treat Hypot 3

Cut-off point: How low is low-dose? 4

Small-dose Low-dose Spinal anesthesia for Cesarean delivery. The dosage dilemma. Finucane BT. Reg Anesth. 1995; 20(2):87 9 Very low-dose Ultra-low dose Ultra-light Walking-spinal anesthesia 5

< 10 mg or < 8 mg (+ opioid) Dyer RA, Joubert IA. (2004) 5 mg to 7 mg ED50=7.6 mg ED95 11.2 mg Ginosar Y,Riley ET (2004) Roofthooft E, van de Velde M. (2008) < ED90-99 < 12.5 mg Kinsella SM (2008) Rucklidge MWM, Paech MJ. (2012) Dyer RA, Joubert IA. Curr Opin Anaesthesiol. 2004;17(4):301 8. Ginosar Y,Riley ET et al. Anesthesiology. 2004;100(3):676 82. Roofthooft E, van de Velde M. Curr Opin Anaesthesiol. 2008;21(3):259 62. Kinsella SM. Anaesthesia. 2008;63(8):822 32.. Rucklidge MWM, Paech MJ. Anaesthesia. 2012;67(4):347 51. 6

Anesthetic Adequacy Anesthetic Efficacy Dermatome level Pain/discomfort Assessment: Cold Pin-prick Touch Surrogate outcomes: Analgesic Supplem. Conversion to GA 7

Anesthetic Adequacy Dermatome level Assessment: Cold * Pinprick * Touch 8

How obstetric anaesthetists test the quality of regional anaesthetic block before caesarean section: A national survey (OAA). Years 2005 and 2011 1. Mode of testing the adequacy of block 2. Documentation 3. Postpartum follow-up Sodhi et al. Int J Obstet Anesth 2005; 14: S8 Liu et al. Int J Obstet Anesth 2011; 20: S39 9

2005 2011 members Cold T4 747/1035 (72%) 45% (90% combined) Cold: 64% Pinprick: 49% Touch: 37% 549/1229 (45%) 36% Cold: 76% Pinprick: 25% T5 - Touch: 37% Lower level block 52% (S 234: 65%) 62% (S2: 42%) 10

2005 2011 Warning pain/discomfort 91% 96% conversion to GA 85% 92% (incidence: 49% range: 0.2-25%) Follow-up Routine: 88% 37-89% Routine: 90% Pain: 87% 11

Anesthetic Adequacy Max sensory block versus time Differential zone: LA concentration, fiber hierarchy, modality of testing Variability of median values of different modality testing Prediction Pain based on sensory block 12

Mean Sensory Block (pinprick) over Time De Simone et al. Reg Anesth. 1995;20(2):90 4. 13

Mean Sensory Block (cold- touch) over Time Sarvela et al. Anesth Analg. 1999; 89(5):1257-62. 14

Mean Differential Block: Cold-Pinprick-Touch x x x x x x x x Russell IF. Int J Obstet Anesth. 2004;13(3):146 52. 15

Differential Block: Cold-Pinprick-Touch Number of segments difference from Touch Russell IF. Int J Obstet Anesth. 2004;13(3):146 52. 16

Sensory modalities: differential block and variability Kocarev et al Int J Obstet Anesth 2010; 19(3):261 5. 17

Sensory modalities: differential block and variability Kocarev et al Int J Obstet Anesth 2010; 19(3):261 5. 18

Sensory block: Is a good/poor predictor of Pain? 19

Pain Free Cesarean Delivery Light Touch T5 sensory block T6 at skin incision (+ opioids) Anesthesia Cold / Pinprick T4 at skin incision Analgesia Russell IF. Int J Obstet Anesth. 1995;4(2):71 7. Russell IF. Int J Obstet Anesth. 2004;13(3):146 52. Sarvela et al. Anesth Analg. 1999; 89(5):1257-62.. 20

IJOA Testing the block for caesarean section Leaving touch out in the cold 100 patients CSE: HypBupiv. 6.27 mg (±0.27) + sufentanil Sitting >> steep Trendelenburg + Left L. tilt Test of sensory block: - - a gauze swab soaked in ether first felt touch and cold Surgery: minimum T3 block to COLD 69% no detectable block to touch Walters MA, van de Velde M. Int J Obstet Anesth 2011; 20: S6. 21

T3 < T3 Pain No Pain Total 4 80 84 4 12 16 Fisher s exact test: p-value=0.021 8 92 100 T6 Pain No Pain Total 0 8 8 < T6 8 84 92 Fisher s exact test: p-value=1.0 (NS) 8 92 100 Walters MA, van de Velde M. Int J Obstet Anesth 2011; 20: S6. 22

IJOA International Journal of Obstetric Anesthesia Pain 95% CI T6 0/8 0% 0-31.2% T3 4/84 5% 1.3% - 11.7% < T6 8/92 9% 3.8% - 16.4% < T3 4/16 25% 7.2% - 52.4% Walters MA, van de Velde M. Int J Obstet Anesth 2011; 20: S6. 23

Dermatome level Assessment: Anesthetic Touch Adequacy Cold Pin-prick 24

Anesthetic Efficacy Pain/discomfort Surrogate outcomes: Analgesic Supplem. Conversion to GA 25

IJOA International Journal of Obstetric Anesthesia Russell et al. Garry et al. Design Prospective (1990-91) n=150 Retrospective (1996-99) n=1610 Spinal dose 10-17.5 mg 11.5-15 mg Supplementation (Elect - Emerg) Conversion to GA (Elect - Emerg) 11.3% (13.5% - 8.2%) - 10.9% (12.2% - 7.7%) 2.9% 0.75% Garry M.Int J Obstet Anesth. 2002;1;11(1):9 12 Russell IF. Int J Obstet Anesth. 1995; 1;4(2):71 7. 26

IJOA International Journal of Obstetric Anesthesia Garry M.Int J Obstet Anesth. 2002;1;11(1):9 12 27

A prospective audit of regional anaesthesia failure in 5080 Caesarean sections: 1999-2004 Spinal* CSE (normal dose) CSE (**low dose) Conversion GA (elective) 0.05% (7 / 1408) 2.4% (3 / 127) 3.8% (1 / 26) Pain (adequate block T4 to ice) 3.26% (101 / 3,094) 13.4% (35 / 261) * 12.5 mg, **Low <12.5 mg Kinsella SM. Anaesthesia. 2008; 63(8):822 32. 28

Visceral pain 29

LD CD Pedersen et al. (1989) 70.5% (7.5-10 mg) 31.6% (10-12.5 mg) Ben-David et al (2000) 50% (5 mg IB. + Fentanyl 25 ug) 12.5% (10 mg IB) Bryson et al. (2007) 18.5% (4.5 mg IsoB + Fenta 50 ug) 4% (12 mg HB. + Fenta 50 Ug) Pedersen et al. Anesth Analg. 1989; 69(1):46-9. Ben-David et al. Reg Anesth Pain Med. 2000; 25(3):235-91. Bryson et al. Can J Anaesth. 2007; 54(7):531 7. 30

Arzola C, Wieczorek PM. Br J Anaesth. 2011;107(3):308 18. 31

C-delivery under Spinal or CSE Low-dose 8 mg, Conventional-dose > 8mg Anesthetic efficacy: - - Analgesic supplementation Conversion to GA Side effects: - - Hypotension, Nausea-Vomiting, Maternal satisfaction Fetal: gases (ph, BE), Apgar score Arzola C, Wieczorek PM. Br J Anaesth. 2011;107(3):308 18. 32

15 studies / 1004 pts. - 12 studies / 693 pts. Years 2000-2010. Source: 4 continents. Bupivacaine 4mg to 12.5 mg. Spinal (10 studies), CSE (5 studies) Dose-sample size : Weigh mean value 7 mg - 11 mg Arzola C, Wieczorek PM. Br J Anaesth. 2011;107(3):308 18. 33

Analgesic Supplementation Favours LD Favours CD Arzola C, Wieczorek PM. Br J Anaesth. 2011;107(3):308 18. 34

Hypotension Favours LD Favours CD Arzola C, Wieczorek PM. Br J Anaesth. 2011;107(3):308 18. 35

Intraop. Nausea-Vomiting Favours LD Favours CD Arzola C, Wieczorek PM. Br J Anaesth. 2011;107(3):308 18. 36

LD CD Analgesic Supplementation 23% 5.3% RR= 3.76 (2.38, 5.92) NNTH= 4 (2, 7) Conversion GA 2 /317 = 0.63% (0.07-2.26) Hypotension RR= 0.78 (0.65, 0.93) Naus-Vom. RR= 0.71 (0.55, 0.93) Arzola C, Wieczorek PM. Br J Anaesth. 2011;107(3):308 18. 37

Low dose - CSE Studies on CSE (methodology): - - - - - - drugs, doses volume of solutions epidural bolus: nature and timing adequacy of the block endpoint for success sample size calculation Standard versus Sequential EVE: epidural volume extension 38

CSE: 3.75 mg Bupiv. 3.75 mg v/s Bupiv. 9 mg + Fentanyl 25 ug Morphine 100 ug Test dose: Lidocaine 1.5% (3 ml) Preload LR 500 ml (10 min) Right Lateral Decubitus Teoh et al. Int J Obstet Anesth. 2006; 15(4):273 8. 39

- Failure ( T6 at 10 min) - Breakthrough Pain (>4/10) Top-ups (+ 5 ml) Lidocaine 1.5% Epinephrine 5 ug/ml Bicarbonate 8.4% (2 ml) Teoh et al. Int J Obstet Anesth. 2006; 15(4):273 8. 40

3.75 mg 9 mg * Max Sensory level T3 (T2-T6) T2 (C2-T6) * Sensory at 10 min T4 (T2-T8) T2 (C6-T6) Intraoperative Pain 13.6% 13.6% * Hypotension (0 episodes) 86% 27% * p<0.05 Teoh et al. Int J Obstet Anesth. 2006; 15(4):273 8. 41

CSE: Supraesternal Doppler Seq./CSE Bupiv. 5 mg + Fenta 15 ug v/s Std./CSE Bupiv. 10 mg + Fenta 15 ug IsoB 0.5% (10 ml) at 15 min + IsoB 0.5% (5ml) at 25 min IsoB 0.5% (5 ml) at 20 min Bray JK, Fernando R et al. Anesth Analg 2006; 103(4):959 64. 42

CSE: Supraesternal Doppler Results - No significant difference hemodynamic lowest values. - No difference: hypotension, ephedrine requirements nausea scores, or fetal outcome Bray JK, Fernando R et al. Anesth Analg 2006; 103(4):959 64. 43

Seq. (5 mg) Stand. (10 mg) Supplem. Analgesia 40% 30% Supplem. Top-up 85% 20% Cold at 15 min Touch at 15 min T5 [7, 4] T7 [9.75, 5] T3.5 [4.75, 3] T5 [6, 3] Bray JK, Fernando R et al. Anesth Analg 2006; 103(4):959 64. 44

CSE: EVE Bupiv. 7.5 mg v/s Bupiv. 7.5 mg (+F) + v/s Bupiv. 10 mg + Fenta 25 ug EVE (5 ml saline) + Fenta 25 ug Failure Top-Ups - T4 at 15 min IsoBupiv. 0.5% - Breakthrough Pain (+ 5 ml) Loubert C, Fernando R et al. Anaesthesia. 2011 ;66(5):341 7. 45

CSE: EVE Loubert C, Fernando R et al. Anaesthesia. 2011 ;66(5):341 7. 46

CSE: EVE Loubert C, Fernando R et al. Anaesthesia 2011 ;66(5):341 7. 47

Bupiv. 6.5 mg + Sufentanil 2.5 ug + EVE 5 ml at 5 min v/s Bupiv. 9.5 mg + Sufentanil 2.5 ug + EVE 5 ml at 5 min - Failure ( T3 cold at 15 min) - Breakthrough Pain Top-ups: Lidocaine 2% van de Velde et al. Anesth Analg 2006; 103(1):187 90. 48

6.5 mg 9.5 mg * Time to T3 (min) 8 ± 2.1 5.5 ± 2.2 Supplem. before/after delivery 0 / 5 (20%) 0 / 2 (8%) * Hypotension 16% 68% * Adequate anesthesia (min) 68 ± 18 min 95 ± 25 * p<0.05 van de Velde et al. Anesth Analg 2006; 103(1):187 90. 49

Bray et al van de Velde et al doses 5 mg 10 mg 6.5 mg 9.5 mg EVE - - 10 ml / 5 min 10 ml / 5 min Bupivacaine 0.5% Lidocaine 2% Top-up timimg 10 ml (15 min) + 5 ml (25 min) 5 ml at 20 min at 5 min interval Bray JK, Fernando R et al. Anesth Analg 2006; 103(4):959 64. van de Velde et al. Anesth Analg 2006; 103(1):187 90. 50

Meta-Analysis_ part II: What if we include the CSE studies? Arzola C. Debate CSE-LD v/s HD-Vasopressors CAS 2012. 51

Arzola C. Debate CSE-LD v/s HD-Vasopressors CAS 2012. 52

Arzola C. Debate CSE-LD v/s HD-Vasopressors CAS 2012. 53

Arzola C. Debate CSE-LD v/s HD-Vasopressors CAS 2012. 54

Arzola C. Debate CSE-LD v/s HD-Vasopressors CAS 2012. 55

Ngan Kee et al. Anesthesiology. 2005 ;103(4):744 50. 56

80 patients : 4 groups 1. CSE Isobaric Bupivacaine 0.5%: 7 mg, 10 mg (+ Sufentanil ) - L2-3, R. Lateral + Coloading 750 ml Crystaloid 2. Phenylephrine infusion: 0.25 ug/kg/min LiDCOPlus: IBP, CO, SV, SVR Rescue Top-up: Failure to T8 (cold)>> 8 ml Chloropro.(30 mg/ml) 57

Bupiv. 7 mg + Placebo Bupiv. 7 mg + Placebo Bupiv. 7 mg + Phenylep. Inf. Bupiv. 10 mg + Phenylep. Inf. Langesæter et al. Anesthesiology. 2008 ;109(5):856 63. 58

Bupiv. 10 mg (2 groups) Bupi 7mg (2 groups) Epid. Supplem. 1 / 40 (2.5 %) 3 / 40 (7.5%) SBP < 20% RR= 1.6 (95% CI, 1.1 2.4) Hemodynamic SBP (p=0.009) CO (p=0.186) *Nausea RR= 4.3 (95% CI, 1.4 12.9) * B10/Placebo vs B7/Phenyl. Langesæter et al. Anesthesiology. 2008 ;109(5):856 63. 59