Labor Labor Term, nulliparous women carrying singleton, cephalic - - PDF document

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10/9/13! 1!

Physiologic partograph to improve birth safety and outcomes among low-risk, nulliparous women with spontaneous labor onset Jeremy L. Neal PhD, CNM, RN

Assistant Professor The Ohio State University

!

Presentation Overview

• Background & Significance!
• Introduction to Partograph!
• Partograph Use Examples!

Birth should be recognized as a normal physiologic process ! Providers should advocate for non-intervention in the absence of complications ! Scientific evidence should be incorporated into clinical practice !

To start…!

Background and Significance Why Nulliparous Women?

• Term, nulliparous women carrying singleton, cephalic

presenting fetuses are of particular interest when strategizing to improve obstetrical care quality and outcomes (CDC, 2012;

ACOG, 2000; Boyle et al, 2012; Main et al, 2004, 2006; Cleary et al, 1996)!

• 40% of all U.S. births are to nulliparous women; 1.6 million in

2011 (Martin et al, 2013)!

• ~97-98% of the variation in overall cesarean rates between

institutions is d/t variation in cesareans to low-risk, nulliparous women (Brennen et al, 2009, 2011) !

• The course of the 1°labor largely dictates the course and

management of subsequent labors!

Labor Labor

• “The presence of uterine contractions of sufficient

frequency, duration, and intensity to cause demonstrable effacement and dilation of the cervix” (ACOG, 2003)!

• 1st Stage = contraction onset → full dilatation!

! Latent phase = contraction onset → ‘active’ dilation onset! ! ‘Active’ phase = ‘active’ dilation → complete dilatation! !

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8 4 3 7 6 5 9 10

Friedman’s Active Phase: Nulliparae

Hrs cm 5 10 15 2

4.9 ± 3.4 hrs (mean) (1955)! Acceleration Phase (~2.5-4 cm) ≈ 2.1-2.4 hrs! Phase of Max Slope (~4-9 cm) = 3.0-3.7 cm/hr! [**computes to 1.35-1.67 hrs]! (Friedman, 1955, 1978; Friedman & Kroll, 1971)! 4.6 ± 3.6 hrs (mean) (1971, 1978)! Deceleration Phase (~9-10 cm) = 0.84-0.9 hr! 11.7 hrs (mean+2 SD) !

(1955, 1971, 1978)!

Phase of Max Slope ! (~4-9 cm) = 1.2 cm/hr! “1 cm/hr rule”!

Nulliparous Labor Curve From ‘Active’ Labor Onset

2 Hrs cm 5 10 15

Dilatations associated with ‘active’ labor onset (Cunningham et al, 2010; Gabbe et al, 2007; Varney et al, 2004)!

8 4 3 7 6 9 10 5

(Friedman, 1955, 1971, 1978)! (Zhang, Troendle et al, 2010)! 7.3 hrs ! (median)! 13.7 hrs (90th %)! (Zhang, Troendle et al, 2002)! (Zhang, Landy et al, 2010)! 16.4 hrs (95th %)!

Nulliparous ‘Active’ Labor

• Peisner & Rosen (1986) (n = 1060)!

!

Using Friedman’s 1.2 cm/hr criteria, low-risk, term, nulliparas with intact membranes, cephalic presentation, and spontaneous labor were evaluated: !

• At 3 cm, 75% were not ‘active’!
• At 4 cm, 50% were not ‘active’!
• At 5 cm, 25% were not ‘active’!
• Neal et al (In review) (n = 216)!

!

Using criteria put forth by the SOGC (1995), i.e., at > 3 cm dilatation, adequate labor involves average dilation of > 0.5 cm/hr over any 4 hr time window:!

• 52.8% did not meet this expectation in the first 4 hrs after admission

(average dilatation at admission ~3.5 cm)!

‘Cer ervicogr icograph’ aph’ (adapt adapted) ed)

(Philpott, 1972; Philpott & Castle, 1972a, 1972b)

3 10 16 8 10 4 6 2 4 6 8 12 14 cm Hrs Alert line Action line Low-risk, Rhodesian primigravidae at ! 3 cm at admission (n = 624) ! 10.9% (n=68) 78.2% (n=488)

• Alert line = dilation expectation of ≥ 1 cm/hr meant to

represent the slowest 10% (based on Friedman work)!

• Action line = if crossed, consider aggressive interventions (e.g.,
• xytocin)!

0.64 cm/hr

10.9% (n=68)

WHO Partograph

WHO Partograph (adapted)

(WHO, 1994)!

3 10 16 8 10 4 6 2 4 6 8 12 14 cm Hrs Alert line Action line 11.7% (n=281) 69.1% (n=1656)

• Evaluated in large, multicenter trial in 1990s (n = 35,484)!
• Reported on subgroup of low-risk, term, nulliparous women

with spontaneous labor onset admitted in ‘active’ labor, i.e., ≥ 3 cm dilatation + contractions (n = 2397)!

0.64 cm/hr!

19.2% (n=460)

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10/9/13! 3!

WHO Partograph (adapted)

(WHO, 2007; Orji, 2008)!

3 10 16 2 4 6 8 12 14 8 10 4 6 cm Hrs Alert line Action line 18.5% (n=48) 65.3% (n=169)

• In 2007, the WHO changed their definition of active labor onset

from 3 cm to 4 cm (WHO, 2007)!

Low-risk, term, Nigerian nulliparas at ! 4 cm at admission (n = 259) !

0.60 cm/hr!

16.2% (n=42)

Nulliparous women assessed via partographs with ‘alert’ and 4-hr ‘action’ lines

Study! Country! Earliest partograph initiation! n! Alert Line Crossed ! (< 1cm/hr)! Action Line Crossed ! (< 0.64 cm/hr)!

Philpott et al. (1972)! Zimbabwe! 3 cm! 624! 21.8%! 10.9%! Drouin et al. (1979)! Cameroon! 3.4 ± 0.6 cm*! 480! 56.3%! 32.3%! WHO (1994)! Indonesia, Thailand, & Malaysia! 3 cm! 2397! 30.9%! 11.7%! Lavender et al. (1998)! England! 3 cm! 311! Not reported! 38.1%! Lavender et al. (1999)! England! 3 cm! 171! Not reported! 37.4%! Pattinson et al. (2003)! South Africa! 4 cm! 350! 49.7%! Not reported! Lavender et al. (2006)! England! 3 cm! 1485! Not reported! 45.3%! Mathews et al. (2007)†! India! 3 cm! 175! 19.4%! 10.9%! 4 cm ! 156! 17.9%! 1.3%! Orji (2008)! Nigeria! 4 cm! 259! 34.8%! 18.5%! van Bogaert (2009)! South Africa! 3 cm! 1595! 34.4%! 10.1%! *! Mean dilatation at “active phase” onset! † 2 partographs with 4-hr action lines were tested in this study!

Active Management of Labor (AML)

• Multifaceted labor management program aimed

to shorten nulliparous labor (O’Driscoll et al, 1973, 1993)!

• Components:!

!

Antenatal childbirth preparation; strict diagnosis of spontaneous labor

• nset; 1-on-1 labor support ; routine amniotomy; routine cervical

assessments; oxytocin if dilation is < 1 cm/hr; peer review of assisted deliveries!

• 55-62% receive oxytocin under AML (O’Driscoll

et al, 1973; Brown et al, 2008)! Studies of Spontaneous Nulliparous Labor (Ø oxytocin, Ø anesthesia)

• Kilpatrick & Laros (1989) (n = 2302)!

!

regular, painful contractions " full dilatation = 8.1 ± 4.3 hrs!

• Albers, Schiff, & Gorwoda (1996) (n = 347)!

!

4 cm " 10 cm = 7.7 ± 5.9 hrs (95th %ile = 19.4 hrs)!

• Albers (1999) (n = 806)!

!

4 cm " 10 cm = 7.7 ± 4.9 hrs (95th %ile = 17.5 hrs)!

• Jones & Larson (2003) (n = 120)!

!

4 cm " 10 cm = 6.2 ± 3.6 hrs (95th %ile = 13.4 hrs)!

• Average dilation rates in these studies range from:!

!

0.8-1.0 cm/hr at the mean!

!

0.3-0.5 cm/hr at the statistical limit!

‘Slowest-Yet-Normal’ Dilation Rate for Nulliparous Women

• Summary: Existing literature indicates that

10-18% of low-risk nulliparous women with spontaneous labor onset dilate <0.5-0.64 cm/hr,

• n average, even after 3 or 4 cm !

(Zhang et al, 2002, 2010; Philpott & Castle, 1972a, 1972b; WHO, 1994; Orji, 2008; Perl & Hunter, 1992; Albers et al, 1996; Albers, 1999; Jones & Larson, 2003)!

• The problem: Clinician expectation of ‘active’

labor dilation is often much faster than the above rates!

Clinical Dilemma

• Either many nulliparous women are admitted

prior to progressive (active) labor yet held to dilation expectations of ‘active’ labor ! and/or !

• Common expectations of active labor dilation

rates (e.g. 1 cm/hr) are unrealistically fast!

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Consequences of Earlier Admission after Spontaneous Labor Onset

• Admissions at < 3 cm (vs. > 3 cm)!

# In-hospital labor time, oxytocin use, epidural use, dystocia

diagnoses, & cesarean deliveries!

$ Satisfaction with birth experience!

! !(McNiven et al., 1998; Impey et al., 2000; Rahnama et al., 2006)!

• Admissions at < 4 cm (vs. > 4 cm)!

# In-hospital labor time, oxytocin use, epidural use, active

phase arrest, & cesarean deliveries!

! !(Holmes et al., 2001; Bailit et al., 2005; Mikolajczyk et al., 2008)!

!

!

p < 0.01 for all findings!

Timing of Admission to Hospital After Spontaneous Labor Onset

• Low-risk, nulliparas at ! 37 wks with a singleton, cephalic fetus

admitted for spontaneous labor onset by their provider (n = 216)!

! 114 (52.8%) were admitted in pre-active labor! ! 102 (47.2%) were admitted in active labor!

• Women in pre-active labor were more likely to undergo:!

! Oxytocin augmentation (84.2% v. 45.1%, respectively; OR 6.5, 95% CI 3.43-12.27)! ! Cesarean delivery (15.8% v. 6.9%, respectively; OR 2.6, 95% CI 1.02-6.37)!

• In addition:!

! All cesareans for dystocia (n = 10) were in pre-active group (p < 0.01) (7 of 10 were performed at ≤ 5 cm)! ! In-hospital labor time >4 hrs longer in pre-active group (p < 0.001)! ! Max temps during labor were higher in pre-active group (p = 0.026)!

!

!

Neal et al (In review)!

Consequences of Unrealistically Fast Cervical Dilation Expectations

↑

diagnoses of dystocia, i.e., “slow, abnormal progression

• f labor” (ACOG, 2003)!

↑

intervention(s) to accelerate labor with inherent risks!

↑

unnecessary cesareans! !

!

!

Dystocia

• “Slow, abnormal progression of labor” (ACOG, 2003)!
• In practice, diagnoses of dystocia are most often based on

ambiguously defined delays in dilation beyond which labor augmentation is deemed justified!

• Consequence: Dystocia is known to be “over-

diagnosed” (Cunningham et al, 2010) !

• Leading indication for primary cesareans accounting for as

much as 50% of all nulliparous cesareans (ACOG, 2000, 2003;

Cunningham et al, 2010)!

Oxytocin augmentation

• Dystocia over-diagnosis largely explains why

approximately 50% of nulliparous women with spontaneous labor onset receive oxytocin augmentation during labor (Zhang et al, 2002, 2010; Treacy et al, 2006; Oscarsson

et al, 2006) !

• This is concerning because oxytocin: !

! is a “high-alert medication” (ISMP , 2008)! ! is the intervention most commonly associated with preventable adverse perinatal outcomes (Clark et al, 2008, 2009) ! ! misuse is involved in half of all paid obstetric litigation claims (Clark, 2008) !

• Any overuse of oxytocin imposes unnecessary risk on

the mother and fetus during labor !

Cesareans

• U.S. cesarean rates among term, low-risk, nulliparous women with

vertex fetus = 26.4% (CDC, 2013)!

• Dystocia accounts for 50% of these (~13%) (ACOG, 2000, 2003;

Cunningham et al, 2010)!

• 90% of primary cesareans are followed by repeats, thus, the majority
• f all cesareans are attributable to the diagnosis of dystocia that

lead to the first (CDC, 2013) !

• Total cesarean rate in U.S. = 32.8% (Martin et al, 2013)!

! Highest rate = Louisiana (39.9%); Lowest rate = Alaska (22.4%)! ! Minnesota (26.8%); Ohio (31.2%)!

• The concern: the best birth outcomes occur with cesarean rates of

5-10% while rates higher than 15% are associated with excessive morbidities and mortality (WHO, 1995; Villar et al, 2006, 2007; Lumbiganon et al,

2010) !

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10/9/13! 5!

• Neal JL, Lowe NK, Ahijevych KL, Patrick TE, Cabbage LA,

Corwin EJ. J Midwifery Womens Health 2010,55:308-318.!

! Aim: to describe labor duration and dilation rates beginning with clinical criteria

• ften used as prospective evidence of active labor onset (i.e. 3 – 5 cm dilatation +

regular contractions) → 10 cm!

! Databases: MEDLINE & CINAHL!

• Cross-searched specific keywords, e.g.,!

nulliparous / nulliparous with labor (labour) length / labor (labour) duration / active phase / active labor (labour)!

• Limited to: 1990 – 2008; English (yield = 375 articles)!

! Qualifying Publications (n = 25)!

! Low-risk, nulliparous women at ! 36 wks with a singleton, cephalic presenting fetus admitted for spontaneous labor onset between 3-5 cm!

Another look at dilation rates in ‘active’ labor… Nulliparous Labor from Criteria Associated with ‘Active’ Labor Onset

2 Hrs cm 5 10 15 8 4 3 7 6 9 10 5

(Friedman, 1955, 1971, 1978)! (Zhang et al, 2002)! 13.4 hrs (mean+2 SD)! (n = 4300)! 0.6 cm/hr! 6.0 ± 2.0 hrs (mean)! (n = 7009)! 1.2 cm/hr! (Neal et al, 2010)!

Problem with Linear Expectation

• f Dilation

!!"#$

% & ' ( ) * + ,- , ) * + & ' % .

/0

"123#4567/8!93:7;<!=76;>5<!?@#A3!?5</32B@;67C3:!;$!D7<3;#

D7<3;#!$6523!E!F/B@;6! :76;>5<!#;B3 F/B@;6!:76;>5<!#;B3!!E! D7<3;#!$6523 Zhang et al, 2002 hyperbolic dilation curve (n = 1162) ! Zhang et al, 2002 hyperbolic curve linearly conceptualized !

Phy hysiologic iologic (non-linear non-linear) expect expectat ation ion

• f
• f dilat

dilation ion

(Zhang, Landy et al, 2010)

• 95th percentile of cumulative duration of labor from admission

among singleton, term, nulliparous women with spontaneous labor onset, vaginal delivery, and normal neonatal outcomes (n = 27,170)!

10 16 2 4 6 8 12 14 Hrs 8 10 4 6 cm 18

Introduction to the Partograph

Physiologically-Based Partograph

• Our research team has developed a partograph for ‘in-

hospital’ use in assessing the labors of nulliparous women with spontaneous labor onset (Neal & Lowe, 2012)!

• We hypothesize that partograph use will:!

! safely limit diagnoses of dystocia during the first stage of labor to only the slowest 10% ! ! ! oxytocin augmentation rates by ≥ 50%! ! ! cesareans performed for dystocia by ≥ 50%!

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10/9/13! 6!

Principles of Partograph

Principle 1.! Active labor onset must be accurately diagnosed before the rate of cervical dilation (cm/hr) is used to assess labor progression.! Principle 2.! Expectations of cervical dilation (cm/hr) for the population must be appropriately-defined.! ! Principle 3.! Cervical dilation rates progressively accelerate throughout the majority of active labor.! ! Principle 4.! The time duration necessary to dilate from one centimeter to the next is more variable in earlier active labor than in more advanced active labor.!

Criteria for Partograph Use!

• Spontaneous labor onset !

! regular, painful contractions (" 2 in 10 min)! ! complete or near complete effacement! ! membranes intact or ruptured! ! bloody show absent or present !

• Initiated with labor and a qualifying cervical exam!

! at 4 cm dilatation if being preceded by cervical change over time (i.e., ≥ 1 cm in ≤ 2 hr window) = earliest start ! ! at ≥ 5 cm regardless of the rate of previous cervical change = direct start!

• Initiated and continued only when no complications

requiring urgent attention through intervention exist!

Partograph for Low-Risk, Nulliparous Women with Spontaneous Labor Onset"

x

• 1:00pm

5:00pm

4

4:00pm

3

3:00pm

2!

2:00pm

1

x

• 3:15pm

6:00pm

5!

7:00pm

6

8:00pm

7

9:00pm

8

Documenting Cervical Examinations

• Cervical exams are crude assessments that rely solely on

the clinical experience and proprioceptive skill of the examiner!

• Clinicians accurately determine actual cervical dilatation

in only half of all cases (Buchmann et al, 2007; Huhn et al, 2004;

Phelps et al, 1995; Tuffnell et al, 1989) !

! Accurate to ± 1 cm in 90% of cases!

• On partograph: dilatations reported as a range are

rounded down to the nearest integer dilatation, e.g., “4-5 cm” is rounded to 4 cm.!

Partograph Use Examples

Example 1: Labor remaining left of the dystocia line without delay

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10/9/13! 7!

Example 2: Labor moving right of the dystocia line Example 3: Labor remaining left of the dystocia line with delay

The ‘Big Picture’

• More than enough research evidence exists to support

the revision of existing ‘active’ labor dilation rate expectations!

• Such physiologically-based revision should improve birth

safety and outcomes by safely:!

! ! diagnoses of dystocia during the first stage of labor ! ! ! oxytocin augmentation rates! ! ! cesareans performed for dystocia!

• Midwives can take a lead in this area and our Hallmarks
• f Midwifery can be the guide !

References

• ACNM. Core Competencies for Basic Midwifery Practice, June 2007. Available at http://www.midwife.org !

ACOG Practice Bulletin Number 49, December 2003: Dystocia and augmentation of labor. Obstet Gynecol 2003;102(6):1445-1454.!

• ACOG. Evaluation of Cesarean Delivery / [Developed Under the Direction of the Task Force on Cesarean Delivery

Rates, Roger K. Freeman ... et al.]. Washington, D.C.: ACOG; 2000.! Bailit JL, Dierker L, Blanchard MH, Mercer BM. Outcomes of women presenting in active versus latent phase of spontaneous labor. Obstet Gynecol 2005; 105:77-9.! Battista LR, Wing DA. Abnormal labor and induction of labor. In: S. G. Gabbe, J. R. Niebyl and J. L. Simpson, editors. Obstetrics: Normal and Problem Pregnancies. Philadelphia:Churchill Livingstone; 2007.! Boyle A, Reddy UM. Epidemiology of cesarean delivery: the scope of the problem. Semin Perinatol 2012;36:308-314.! Brennan DJ, Robson MS, Murphy M, et al. Comparative analysis of international cesarean delivery rates using 10- group classification identifies significant variation in spontaneous labor. Am J Obstet Gynecol 2009;201:e1-e8.! Brennan DJ, Murphy M, Robson MS, et al. The singleton, cephalic, nulliparous woman after 36 weeks of gestation: contribution to overall cesarean delivery rates. Obstet Gynecol 2011;117:273-279.! Brown HC, Paranjothy S, Dowswell T, Thomas J. Package of care for active management in labour for reducing caesarean section rates in low-risk women. Cochrane Database Syst Rev 2008:CD004907.!

!

References

Bugg GJ, Siddiqui F, Thornton JG. Oxytocin versus no treatment or delayed treatment for slow progress in the first stage of spontaneous labour. Cochrane Database Syst Rev . 2011:CD007123.! Buchmann EJ, Libhaber E. Accuracy of cervical assessment in the active phase of labour. BJOG 2007;114(7):833-837. !

• CDC. Healthy People 2020. Accessed August 1, 2013.!
• CDC. Healthy People 2020 Summary of Objectives. Available at:

http://www.healthypeople.gov/2020/topicsobjectives2020/pdfs/MaternalChildHealth.pdf. Accessed January 10, 2012. !

• CDC. Rates of cesarean delivery – United States, 1993. MMWR 1995; 44(15):1-4.!

Clark SL, Simpson KR, Knox GE, Garite TJ. Oxytocin: new perspectives on an old drug. Am J Obstet Gynecol . 2009;200:35.e1-35.e6. ! Clark SL, Belfort MA, Dildy GA, Meyers JA. Reducing obstetric litigation through alterations in practice patterns. Obstet Gynecol . 2008;112:1279-1283. ! Cleary R, Beard RW, Chapple J, Coles J, Griffin M, Joffe M et al. The standard primipara as a basis for inter-unit comparisons of maternity care. Br J Obstet Gynaecol 1996; 103:223-9.! Cunningham, FG, Leveno, KJ, Bloom, SL, Hauth, JC, Rouse, DJ, Spong, CY, editor. Williams obstetrics. 23rd ed. New York: McGraw-Hill; 2010.! Friedman EA, editor. Labor: Clinical evaluation and management. 2nd ed. New York: Appleton-Century-Crofts; 1978.! !

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