Abnormal Presentations, Prematurity, VBAC

1. Abnormal Presentations,Prematurity, & VBAC Joe Dietrick, CRNA, M.A. Truman Medical Center Kansas City, MO

2. Objectives Identify the three parameters associated with fetal presentation Understand the anesthetic implications of the most common abnormal presentations Define prematurity, PROM, and PPROM, and the anesthetic implications Discuss current guidelines for vaginal birth after cesarean (VBAC) & the anesthetic implications

3. Presentation Parameters Presentation: portion of fetus over the pelvis Cephalic (vertex, brow, face) Breech (frank, complete, incomplete) Shoulder Lie: alignment of fetal-maternal spines Longitudinal Transverse Position: relationship of designated part to pelvis 3 parameters3 parameters

4. Normal Presentation Occiput anterior (OA) implies: Cephalic vertex presentation Longitudinal lie Occiput of fetal head towards maternal pubic bone Fetus normally rotates to this position from occiput transverse or occiput oblique

5. Normal Presentation

6. Persistent Occiput Posterior (OP)1 Occurrence 5%, N > 6k, 8% (15 yr study, MFNM, 2006) Historically higher [LA] believed to have contributed; cause:effect difficult - epidural due to incr pain w/OP? Occurrence 5%, N > 6k, 8% (15 yr study, MFNM, 2006) Historically higher [LA] believed to have contributed; cause:effect difficult - epidural due to incr pain w/OP?

7. Persistent Occiput Posterior (OP)1 Back pain – sacral nerve roots Prolonged labor, esp. 2nd stage Cervical/perineal lacerations more common Epidural-induced pelvic floor relaxation implicated – not proven Persistent vs. rotation from OA Low [LA] + Opioid, consider opioid bolus May need assisted delivery (+3) ? ? LA Need good strength to help deliver SVD: 1:4 nulliparous, 1:2 multiparous; incr EBL & PP infection B&WH/Boston Ponkey SE, et al. Persistent fetal occiput posterior position: obstetric outcomes. Obstet Gynecol May 2003;101:915-20. Incr risk of anal sphincter tear; Risk factors for anal sphincter tear during vaginal delivery. Fitzgerald MP, Obstet Gynecol. 2007 Jan;109(1):29-34. Assisted delivery or CS, dbl risk of PP hemorrhage. Associated factors and outcomes of persistent occiput posterior position: A retrospective cohort study from 1976 to 2001. Cheng, Yvonne W.; Journal of Maternal-Fetal & Neonatal Medicine, Sep2006, Vol. 19 Issue 9, p563-568, Need good strength to help deliver SVD: 1:4 nulliparous, 1:2 multiparous; incr EBL & PP infection B&WH/Boston Ponkey SE, et al. Persistent fetal occiput posterior position: obstetric outcomes. Obstet Gynecol May 2003;101:915-20. Incr risk of anal sphincter tear; Risk factors for anal sphincter tear during vaginal delivery. Fitzgerald MP, Obstet Gynecol. 2007 Jan;109(1):29-34. Assisted delivery or CS, dbl risk of PP hemorrhage. Associated factors and outcomes of persistent occiput posterior position: A retrospective cohort study from 1976 to 2001. Cheng, Yvonne W.; Journal of Maternal-Fetal & Neonatal Medicine, Sep2006, Vol. 19 Issue 9, p563-568,

8. Breech2 Buttock presentation, longitudinal lie Position assessed by sacrum Three types Frank: hips flexed, knees extended, stable Complete: hips flexed, knees flexed, may ? to incomplete Incomplete: hips flexed, knees flexed, foot presentation 3-4%3-4%

9. Breech In order of incr freq. Complete: 5 – 10% Incomplete/Ftling: 10 – 30% Frank: 50 – 70%In order of incr freq. Complete: 5 – 10% Incomplete/Ftling: 10 – 30% Frank: 50 – 70%

10. Breech2 More common: premature > term Uterine distension / relaxation Uterine / pelvic abnormalities Fetal abnormalities Variety of obstetric conditions Previous breech Placenta previa Compare to Malampatti Distension: polyhydram. Uterine: bi-cornate “heart shaped” uterus Fetal: anencephaly. Compare to Malampatti Distension: polyhydram. Uterine: bi-cornate “heart shaped” uterus Fetal: anencephaly.

11. Breech: Risk3 Neonatal outcome – worse with vaginal delivery 3 meta-analyses Cheng: Cord prolapse (7.4%), Head entrapment (8.5%) Most studies: slight ? in maternal M&M Hannah (2000): 5% (Vag) vs 1.6% (CS) mortality or serious morbidity No diff in maternal outcome Neonatal: Incr risk with incomplete forms. Metaanalysis: Vs. CSNeonatal: Incr risk with incomplete forms. Metaanalysis: Vs. CS

12. Breech: Anesthesia2 External Cephalic Version (ECV) Offered to all appropriate patients Complications: placental separation, umbilical cord compression/prolapse, hemorrhage, fetal BRADYcardia Anesthesia?4 Success No anesthetic 32% (N=34) SAB 7.5.mg Bupiv 67% (N=36) 30 - 80% successful Change in ACOG guidelines >37 wks Weinger 2007 Pain Scale (VAPS) 1.7 vs. 6.9 Most prev SAB studies had (inadequate) analgesic dose.30 - 80% successful Change in ACOG guidelines >37 wks Weinger 2007 Pain Scale (VAPS) 1.7 vs. 6.9 Most prev SAB studies had (inadequate) analgesic dose.

13. Breech: Anesthesia ACOG Guidelines revised 20065 Allow SVD with appropriate experience Must have protocols for eligibility & management “detailed patient informed consent” CS most common2 Regional anesthesia Uterine relaxation may be inadequate NTG 50 ?g IV Prev based on outcome of Term Breech Trial Collaborative Group CS: uterine relaxation – no head to grab.Prev based on outcome of Term Breech Trial Collaborative Group CS: uterine relaxation – no head to grab.

14. Breech: Anesthesia2 Vaginal delivery (frank or complete only) Normally spontaneous Less freq assisted; no induction or augmentation Increased M&M Epidural desirable Pain relief Inhibition of early pushing Option for CS or perineal dosing for delivery of head Us: delivery in CS room; neonate resusc. Assisted only after deliv past fetal umbilicus Assisted only after deliv past fetal umbilicus

15. Breech: Anesthesia2 “Holy ___ Batman”: Fetal head entrapment Cervical incisions Uterine & cervical relaxation Epidural NTG? CS, with fetal replacement……. Cervix has only 20% smooth muscle Really, not much to do unless going to CSCervix has only 20% smooth muscle Really, not much to do unless going to CS

16. Other presentations2 Face – 70-80% deliver vaginally Brow – CS Compound vertex (arm) CS for cord prolapse or failure to progress Shoulder (not shoulder dystocia) Transverse lie May attempt ECV Normally CS Brow – neck hyperextension Brow – neck hyperextension

17. Preterm Labor & Delivery Premature rupture of membranes PROM: ROM before onset of labor PPROM: PROM + prematurity ACOG #80, 20076 = 34 wks: induce & deliver ? 31 weeks: expectant management “tweener”: evaluate fetal lung maturity Abx prophylaxis 10% PPROM increased risk of abruption: 29-32 wks = 13% ACTA Scand Good et al (2010, Ob/Gyn) 52% of Meth users ? preterm delivery No longer suggests expectant management for >34wks, or tocolysis earlier. Consider risks of ABX & chorioamnionitis10% PPROM increased risk of abruption: 29-32 wks = 13% ACTA Scand Good et al (2010, Ob/Gyn) 52% of Meth users ? preterm delivery No longer suggests expectant management for >34wks, or tocolysis earlier. Consider risks of ABX & chorioamnionitis

18. Shoulder Dystocia2 Vaginal delivery of vertex presentation Anterior shoulder trapped under pubic bone after delivery of head Umbilical cord trapped in pelvis “Recognition that should dystocia exists often is followed by (calmness) giving way to panic.” Outcomes Fetal death, brachial plexus injury Maternal hemorrhage Stories: ABG, residents, hair stylist Sue <1% Maternal hemorrhage: due to uterine atony, vaginal lacerationsStories: ABG, residents, hair stylist Sue <1% Maternal hemorrhage: due to uterine atony, vaginal lacerations

19. Shoulder Dystocia2 Risk factors Macrosomia Maternal DM Previous shoulder dystocia Labor components Delayed active phase Prolonged second stage Operative vaginal delivery Obesity, post-dates Macrosomia: increase in body size relative to head Obesity, post-dates Macrosomia: increase in body size relative to head

20. Shoulder Dystocia2 OB management Suprapubic pressure Hyperflexion of maternal hips (McRobert’s) Vaginal maneuvers Extend episiotomy Rotate posterior shoulder (corkscrew: Woods) Deliver posterior arm Deliberate clavicular fracture Cephalad replacement (Zavanelli) ? CS

21. Shoulder Dystocia2 Anesthesia You can’t do anything about the problem Prepare for STAT CS. Uterine relaxation? May help relieve Allows cephalad replacement Drugs Nitroglycerin 50-100 mcg IV ? Terbutaline 0.25 mg SQ General anesthesia/volatile agents Not an issue of uterine tone, pelvic floor toneNot an issue of uterine tone, pelvic floor tone

22. VBAC & TOLAC VBAC: vaginal birth after cesarean One “attempts VBAC” until one has delivered TOLAC: trial of labor after cesarean technically more correct, but rarely used Risks Uterine rupture (0.5 – 0.9% for low tranverse)8 Factors:7 no prev SVD mult CS induced/augmented labor: 100/124 ruptures received oxytocic Incidence decreasing of VBAC: 28% (1996) ? <10% (2002) Successful vag deliv: 60-80% Maternal deaths (meta review OB/GYN 2005) – none or no difference Fetal outcome: (limited data) – one study had 2x fetal death, others had no patternIncidence decreasing of VBAC: 28% (1996) ? <10% (2002) Successful vag deliv: 60-80% Maternal deaths (meta review OB/GYN 2005) – none or no difference Fetal outcome: (limited data) – one study had 2x fetal death, others had no pattern

23. VBAC & TOLAC7 Perinatal mortality Lead with Dr. Youngblood’s topic” should all women deliver by CS?” Welishar & Quirk in UpToDate Online ERCD: elective repeat cesarean delivery Data from JAMA 2002. Though higher than CS or MP delivery, not different than primipLead with Dr. Youngblood’s topic” should all women deliver by CS?” Welishar & Quirk in UpToDate Online ERCD: elective repeat cesarean delivery Data from JAMA 2002. Though higher than CS or MP delivery, not different than primip

24. VBAC: ACOG Practice Bulletin #115, 20108 Safety: VBAC > Elect Repeat CS > Failed TOLAC Changes – OK for…. 2 previous LTCS – Ext Cephalic Version Twin (prev LTCS x 1) – Induction Unknown uterine scar (unless classical highly likely) Staff availability Patient autonomy allows acceptance of increased levels of risk after being clearly informed. Issues of staffing, reimbursement, & risk. Differentiate between skin & uterine incision 2 CS: recent study states double risk statistically, but overall risk is low Uterine Rupture symptoms not inhibited by normal LEA; What does Immediately Available mean?Issues of staffing, reimbursement, & risk. Differentiate between skin & uterine incision 2 CS: recent study states double risk statistically, but overall risk is low Uterine Rupture symptoms not inhibited by normal LEA; What does Immediately Available mean?

25. OB Litigation10 Clark et al (2008) : OB physician ligation reduction by In-house 24° CS team coverage Adherence to protocols for high-risk medications Improved procedure note in shoulder dystocia More conservative approach to VBAC 2000-2006 CCD review for perinatal claims. (single insurer),N=189 1. Actually stated CS capable Dr,, Anesthesia, OR staff. Not considered standard of care in most locations however. 2. Pit, Mag, misoprostol 3. Documentation problematic 4.Not recognizing uterine rupture, & delayed CS. State that, after the fact, juries interpret “immed available” more narrowly than practitioners2000-2006 CCD review for perinatal claims. (single insurer),N=189 1. Actually stated CS capable Dr,, Anesthesia, OR staff. Not considered standard of care in most locations however. 2. Pit, Mag, misoprostol 3. Documentation problematic 4.Not recognizing uterine rupture, & delayed CS. State that, after the fact, juries interpret “immed available” more narrowly than practitioners

26. VBAC selection10 Parameters TOLAC for spontaneous labor only Normal labor curve w/o augmentation Absence of repetitive mod/severe decels Outcome ? uterine rupture ? adverse neonatal problems Reduction in uterine rupturesReduction in uterine ruptures

27. References Gorman Maloney. S & Levinson, G (2001). Anesthesia for Abnormal Positions & Presentations, Shoulder Dystocia & Multiple Births. In Hughes, et al (Ed), Shnider & Levinson’s Anesthesia for Obstetrics, 4th Ed. (pg 287). Philadelphia: Lippincot Williams & Wlikins, Koffel, B. (2004). Abnormal Presentation & Multiple Gestation. In D. Chestnut (Ed.), Obstetrical Anesthesia: Principles & Practice (pp. 623-639). Philadelphia: Elsevier Mosby. Pratt, S. (2003). Anesthesia for Breech Presentation & Multiple Gestation. Clinical Obstetrics & Gynecology, 46(3), 711-729. Weiniger et al (2007). Spinal Analgesia for External Cephalic Version. OBSTETRICS & GYNECOLOGY,110(6), 1343-1350. ACOG Committee Opinion, No. 340 (2006). Term Singleton Breech Delivery. OBSTETRICS & GYNECOLOGY, 108(1), 235-237. ACOG Practice Bulletin No. 80 (2007). Premature rupture of membranes. OBSTETRICS & GYNECOLOGY , 109(4), 1007-1019. Welischar, J, & Quirk, J (2009). Trial of labor after cesarean delivery. Retrieved 04/03/09 from UpToDate. Website: http://uptodateonline.com/online/content/topic.do?topicKey=labordel/9085&selectedTitle=1~150 ACOG Practice Bulletin No. 115 (2010). Vaginal Birth After Previous Cesarean Delivery . OBSTETRICS & GYNECOLOGY, 116(2), 450-463. Yamamura Y, et al (2006). Trial of vaginal breech delivery: current role. Clin Obstet Gynecol, 50(2):526-36. Clark, S. et al (2008). Reducing Obstertic Litigation Through Alterations in Practice Patterns. OBSTETRICS & GYNECOLOGY, 112(6):1279-