# Presentation: 025539

## VBACIs There Such a Thing as Low Risk?

- Michele R. Lauria, MD
- Associate Professor
- Departments of Ob/Gyn and Radiology
- Dartmouth Hitchcock Medical Center
- Medical Director NNEPQIN

## Objectives

- Risk factors associated with uterine rupture
- Risks of ERCS vs TOL
- How did the VBAC controversy start?
- Social/Economic Impact of VBAC Decline
- An Evidence Based Approach
- The VT/NH VBAC Project

## History of Availability

- 1980s: “30 minute rule”
- ACOG, ASA, AAP
- Cesarean delivery personnel onsite within 30 minutes of the decision...
- 1990: JCAHO adopts “30 minute rule”
- 1990’s:  Managed care; mandated TOL
- 1999: ACOG Practice Bulletin:  				“immediately available”
- 2000: Local Definition ACOG & ASA
- 2001: JCAHO adopts same language
- 2001:  Lyndon Rochelle
- 2002:  VBAC services start closing

## ACOG 2000

- VBAC is an elective procedure
- ... in institutions equipped to respond to emergencies with physicians immediately available to provide emergency care.
- ... definition of immediately available personnel and facilities remains a local decision based on each institution’s  available resources and geographic location.

## Incorrect PremisesMy Opinion

- VBAC is an elective procedure
- Birth is not elective
- VBAC is a choice
- ACOG: UR rate is at least 1%
- Most studies over estimate due to poor ICD-9 codes
- Treat all VBAC equal
- Elective Repeat Cesarean Section is safer
- Increased respiratory complications ERCS vs VBAC
- Law Suit  Poor care or adverse outcome

## ACOG and the American Society of Anesthesiologists 2001

-      Availability of anesthesia and surgical personnel to permit the start of a cesarean delivery within 30 minutes of the decision to perform the procedure; in cases of vaginal birth after cesarean delivery (VBAC), appropriate facilities and personnel, including obstetric anesthesia, nursing personnel, and a physician capable of monitoring labor and performing cesarean delivery, immediately available during active labor  to perform an emergency cesarean delivery.  The definition of immediately available personnel and facilities remains a _local decision_ based on each institution’s  available resources and geographic location.
- ACOG Committee Opinion, #256, May 2001

## ASA Editorials

- Anesthesia staffing for obstetrics... There are no specific answers to such questions, as each must be individualized for the local situation and resources.
- ASA, ACOG and AAP are recommendations and guidelines rather than standards

- ASA October 2000 Newsletter.  Marianna Pl Crowely, MD, chair, Committee on Obstetrical Anesthesia.  Obstetric Anesthesia:  Recent Guidelines for Our Availability to the Labor Floor.

## JCAHO

- “Hospitals providing obstetric or emergency operative services can provide anesthesia services within 30 minutes after anesthesia is deemed necessary”
- “In organizations providing labor services for patients seeking vaginal birth after previous cesarean delivery, appropriate facilities and personnel, including obstetric anesthesia and nursing personnel, are immediately available to perform cesarean delivery while conducting labor for women with a prior uterine scar”
- References local definitions from ACOG/ASA statement

- 2001 JCAHO Standards for Sedation and Anesthesia Care

## Lyndon Rochelle

- Retrospective cohort WA using ICD-9
- Linked with birth certificate
- 1987-1996 primips with prior c/s
- Type NOT specified
- Rates of rupture
- 0.16% with elective repeat
- 0.52% SOL
- 0.77% IOL no PG
- 2.45% IOL with PG

## Problems In General with Studies

- Are all live, non-anomalous fetuses?
- more aggressive with IUD, CM
- Ascertainment bias
- After TOL more likely to call defect a UR
- ICD-9 codes inaccurate (NH, MA x2)
- 50% not UR, include extensions, more likely with TOL
- 50% not symptomatic UR
- Temporal trends with declining PVP
- What do you compare complications to?
- How is the denominator determined
- Are all really TOL candidates
- How many prior classical c/s or unknown scars included
- How many had > 2 cesarean deliveries?

**Notes:**
665.0 and 665.1 are the most common
674.1 also
Over codes by 50% for rupture (MA, NH, WA)
Intra-operative extension
Incidental dehiscence
Of true rupture, < 50% were severe
NH, MA, 
Allows extension at time of c/s
Potentials for bias
After TOL thinned LUS, extension more likely
Diagnosis bias
Says nothing about symptomatic rupture
Have seen temporal trends... PPV has been declining.
Registry codes linked with ICD-9
NH experience:  
CDC 200 states use of hospital discharge data in inaccurate

## Criticism Lyndon-Rochelle

- Most of the above
- Combines 80 UR @ TOL with 11 UR @ ERCS
- Can’t determine if  postpartum complications due to TOL
*Parrish 1989*: WA linked files
-  IOL sens 71.7%, PVP 80.4%
- VBAC only 84.6% coded with combined data, lowest was 25% at one hospital

## Slide 12

## The Problem

- 12% of pregnant women  a prior c/s *Sachs*
- Elective Repeat Cesarean Section (ECRS)
- accounts for 38% of all cesarean sections
- rate is increasing
- C/S is the 3rd most common procedure in NH

## Slide 14

## TOL vs ERCS Complications

- Uterine Rupture (UR)
- Perinatal Demise
- Neonatal impairment
- Hysterectomy
- Bladder injury
- Transfusion
- Infectious morbidity
- Complications of vaginal delivery

## Uterine Rupture (UR)

- Williams Obstetrics:  “Separation of the old uterine incision throughout  most of its length, with rupture of the fetal membranes so that the uterine cavity and the peritoneal cavity communicate.  In these circumstances, all or part of the fetus is usually extruded...”
- Complete disruption of all uterine layers AND
- intraperitoneal or vaginal hemorrhage
- Need for hysterectomy
- Bladder injury caused by scar disruption
- Extrusion any portion of fetal-placental unit
- c/s for non-reassuring FHT or  suspected UR

## Uterine Dehiscence

- Williams Obstetrics: ... “fetal membranes are not ruptured and the fetus is not extruded into the peritoneal cavity” ...

## Potential Risk Factors UR

- Incision type and closure
- IOL
- Pitocin
- PGE
- Foley
- Augmentation
- Prior VBAC
- Inter-delivery interval
- Arrest disorders
- Prior C/S indication
- Maternal and Gestational Age

## Slide 19

## Overall UR Rate

- Miller N=17,000 1982-83 0.7%
- McMahon N= 3000, 0.3%
- Mozurkewich N= 47,000 0.4%
- Zelop N= 2774 0.7%
- Farmer N= 7625 0.8%

## SOL without augmentation

- Zelop 0.4%
- Ravasia 0.45%
- Lyndon Rochelle 0.5

## Prostaglandins

- PGE Gel
- Zelop 3.9% rr 3.2 (0.9-10.9)
- Ravasia 2.9% (rr ~6) p=0.004
- Lyndon Rochelle 2.45%
- Flamm 1.3% (rr~2)  NS
- PGE + Pit: Zelop 4.5%
- Misoprostol
- Wing 2/17 ruptured
- Cervadil
- Minimal data separately
- Often included in PGE preparation

## Foley Balloon/No PG

- Foley:  Ravisia:  0.76%  NS
- 118/129 also received Pitocin
- Pitocin started after Foley expelled
- No PG IOL:  Lyndon Rochelle: 0.7%
- Unclear if this is different from SOL

## Pitocin

- Labor Induction
- Leung no increase risk
- Zelop rr 4.6 (1.5 - 14.1)
- Ravisia rr~2, NS
- Labor Augmentation
- Zelop rr 2.3 (0.8-7.0)
- If used for arrest of dilation
- Pitocin in General
- Flamm rr 3

## Inter-pregnancy interval

- Esposito: _<_ 6 mos  RR 3.92 p=0.02
- time from delivery to conception
- linear trend present but p = 0.06
- Shipp: _<_ 18 mos RR 3.0 (1.2 - 7.2)
- time from delivery to delivery
- is same time as Esposito

## Layers of uterine closure

- Bujold OR increased 5.2
- Canadian retrospective chart review
- Methodology is good
- Use a chromic equivalent
- Zelop: no increase 1984-96
- Phone call:  few single layer closures
- Durnwald:  SMFM oral, adequate power
- No increased risk UR
- Increased windows

## Number of prior c/s

- Many case series of 2 c/s and VBAC
- Large studies say risk increased
- Leung rr 2.6
- 5/13 UR on presentation had 3-4 prior c/s
- 1 c/s 0.66%
- 2 c/s 2.3%
- 3 c/s 2.8%
- Miller rr 3.1 (1.95-4.79)
- Caughey OR 4.8 (1.8-13.2)
- 1 c/s 0.8%
- 2 c/s 3.7%

## Indication for Prior C/S

- Leung no increase with c/s for CPD
- Several other large studies, similar

## Prior successful VBAC

- Is not completely protective
- Zelop: controlled for IOL etc
- rr 0.2 with prior VD
- includes VD prior to c/s
- Had 2 ruptures after 2 successful VBAC
- Leung 16/93 had prior VBAC
- Increases successful TOL

## Gestational Age

- Zelop
- No increase rupture < or > 40 weeks
- Increase success if SOL < 40 weeks
- Decrease if IOL < 40 weeks
- No difference if wait for SOL at > 40 weeks
- Await SOL even after 40 weeks maintains rupture rate and success rate.

## Maternal Age

*Shipp 2002*: Increased risk with maternal age
- Controlled for birth weight, IP interval, IOL and AOL
- <30   	~ 0.4
- 30 - 34  ~1.3
- 35 - 39  ~1.4
- >39   	~ 2.4
- Other studies control for maternal age
- Independent confirmation is warranted

## Epidural

- Probably no effect on UR
- Studies somewhat inconsistent
- Risk factors epidural also risks for failed VBAC & arrest disorders.

## Arrest Disorder

- Leung:  31/70 had dysfunction labor, mostly arrest dilation
- Documented by IUC showing adequate uc >= 2 hours
- Appropriate c/s would have prevented rupture
- Hamilton: Case control
- UR labored 5.5 hours longer after dx arrest dilation
- Best dx: lack of dilation _>_ 2 hours @ _>_ 3 cm
- Prompt c/s prevent 31-42% UR
- study used 5 definitions

**Notes:**
Hamilton: Case control
UR labored 5.5 hours longer after dx arrest dilation
15/19 were first stae rupture, all at dilation >= 3,  mean was 5.6 cm
found women with rupture labored on average 5.5 hours longer after arrest of dilation than women with failed VBAc, who only labored 1.45 hours after diagnosis of arrest of dilation.
Had 5 ways of diagnosing arrest of dilation
have a labor curve support tool
lack of dilation for >= 2 hours once at least 3 cm dilated... this was the best
Found lack of dilation for >2 hours at >= 3 cm occurred in 47% cases of rupture, 55% cases of failed VBAC
Prompt cesarean section for arrest of dilation would have prevented 31-42% of uterine ruptures depending of definition of arrest disorder... 31% using conventional definition.

## MFMU Cesarean Registry TrialMB Landon

- Prospective 4 year cohort 1999-2002
- 19 Academic centers
- Singletons with prior CS
- Chart review by research nurses
- Compared TOL to ERCS
- ERCS:  No other indications and no labor

## MFMU Cesarean Registry TrialMB Landon

- 45,981 women with prior c/s
- 15,800 ERCS
- 17,931 TOL (39%)
- VBAC Success: 73%

## MFMU Cesarean Registry TrialMB Landon

|  | TOL
N=17292 | ERCS
N=15793 | RR | p |
| --- | --- | --- | --- | --- |
| UR | 0.78 | 0 | -- | 0.0001 |
| Hysterectomy | 0.23 | 0.3 | .77 | NS |
| DVT/PE | 0.04 | 0.06 | 0.62 | NS |
| Transfusion | 1.7 | 1.0 | 1.71 | 0.0001 |
| Endometritis | 2.9 | 1.8 | 1.61 | 0.0001 |
| Death | 0.02 | 0.04 | 0.38 | NS |
| IP SB | 0.05 | 0.02 | 2.28 | NS |
| NND | 0.08 | 0.04 | 1.96 | NS |
| HIE | 0.09 | 0.01 | 13.73 | 0.001 |

## MFMU Cesarean Registry TrialMB Landon

**Conclusion:** trial of labor remains an option as the absolute risk for these complications is small.

## Slide 38

## Risks for Uterine Rupture

- Clearly Increased
- Pitocin
- Prostaglandin
- 2 or more prior cesarean sections
- < 18 months since prior delivery
- Arrest disorder
- Possibly Increased
- AMA
- Single layer closure
- Mechanical methods of ripening

- No Increase
- Epidural
- Macrosomia
- Gestational Age
- Indication prior c/s

## Summary UR

- Uterine Rupture
- 			_**Rageth       Ravasia        LR       Mozur**_
- No h/o CS       0.0075%
- ECS                 0.19%                          0.16%     0.16%
- SOL                 0.40%         0.45%      0.52%
- IOL Prost                            2.9%        2.45%
- IOL no Prost                      0.73%       0.77%

**Notes:**
So what are the true risks of uterine rupture?

Read slide

## Signs of UR

- Dystocia present in 40% of cases
- Repetitive variable or late decelerations
- Abnormal FHR pattern in 70-80%
- Decreases time until neonatal injury
- Pain is a late and rare finding
- Bradycardia is a late finding
- Abruption decreases time

## 10 Minutes

- Leung et al, Am J. OB/GYN 1993

- 32 Minutes

## Fetus: Risks ERCS

- Respiratory: vs Vag Delivery* Levine*
- TTN 3.5% vs 1.1% p<0.001
- RDS 0.2 vs 0.1% NS
- PFC 0.37% vs 0.08% p<0.001
- Respiratory vs TOL *Hook*
- TTN 6% vs 3%
- Any respiratory complication RR 2.3 (1.4, 3.8)

## Fetus: failed VBAC vs ERCS

- Increase infectious morbidity
- Hook 2% vs 0% (3 cases vs 0) proven  sepsis
- Hook 12% vs 2% suspected sepsis
- No increase in respiratory complications Levine
- Hook:  Surprising number of routine VD have extra procedures done.  Need for control group.

## UR Risk of Fetal Death/Injury

- Make sure they were all alive at start
- Need standardized assessments of injury
- Yap: 0/19 intrapartum M&M
- Lueng: 2/86 death, 4/86 asphyxia
- Farmer:  1/61 death
- LR:  5/91 death
- Bujold: 1/23 death, 2/23 ? Asphyxia
- Overall 3.2% risk death, 5.5% injury
- Standard quote 10% or overall 0.05 or 1/2000
- MBL:  0.17% TOL vs 0.07%, excess 0.1%

## Maternal Injury with UR

- Cesarean hysterectomy
- 10%-20%
- Urologic injury
- Farmer15/61
- Lyndon-Rochelle 7/91
- Transfusion
- overall higher rates with repeat c/s
- Need comparison of ERCS vs failed TOL
- Baskett 33%
- Farmer 13/61
- Death:  0-1%

## Slide 47

## Social/Economic Impact

- C/S is 3rd most common procedure in NH
- ERCS accounts for 38% of all C/S
- HCUP Data:  $3,785 for C/S vs SVD
- Increases cesarean section rate
- NH & VT 372 extra C/S 2002
- > $ 7 M/adverse neonatal outcome from UR
- No choice for many women
- Nearest hospital offering VBAC > 1 hour away
- Prior successful VBAC forced to C/S
- Parking lot labors

**Notes:**
HCCUP:  Heatlh Care Cost and Utilization PRoject

## How VBAC Effects You

- 11% - 12.5% all pregnant women prior c/s
- Pre-2000:  *40*% will attempt
- 0.4 x 0.12= 0.05 or 5% of your patients will present for VBAC
- 80% will be low risk
- Service of 200
- 10 VBAC/year
- 2 Medium or High risk

## VT/NH VBAC Project

- Goal:  Increase VBAC availability and safety for patients and providers
- Collaborative Creation Regional
- Protocol
- Consent form
- Patient Education Tool
- October 4, 2002 Official Release
- Matches resources to risk

## VT/NH VBAC Project:  Process

- All Hospitals NH and VT
- OB, anesthesia, administrators, med mal and health insurers, nursing, public health departments
- 180 first meeting, 50 for 5 follow up
- April 22:  Literature review
- Combined materials from all hospitals
- 5 Follow ups: Open collaboration

## VT/NH VBAC Project

- Regional Materials
- Consent
- Education
- Protocol
- Available at NNEOB.org
- Decided to form a QI Network
- 22 of 35 hospitals thus far have endorsed
- No reply
- Not offering VBAC and thus not discussing
- Hadn’t reviewed yet

## Protocol

- Rigorous definitions
- Admission
- OR personnel
- Anesthesia personnel
- Matches resources to risk
- Of UR
- Of fetal injury
- No times
- Defines availability by location and activity
- Advises against use of prostaglandins

## Protocol

- Low Risk: SOL, 1 c/s, normal tracing
- Notify anesthesia, OR, Pedi of admission
- OB on campus active phase
- Comply with _Guidelines for Prenatal Care _
- Medium risk: 2 c/s, augmentation, IOL, < 18 mos
- Anesthesia on campus active phase
- OR on campus active phase or plan in place if OR busy

## Protocol

- High Risk Definition
- Abnormal FHR pattern, not resolving
- No change in 2 hours despite adequate labor
- Bleeding like an abruption
- High Risk Resources
- Everyone available
- No other acute patient care responsibilities
- Rapid movement from decision to incision

## Anesthesia Recommendations

- Protocol
- Antepartum consultation
- MD available trained in conscious sedation
- ER physician
- Additional Suggestions
- C/S under local protocol
- Nurse dedicated to helping anesthesia
- Intrapartum consult and set up table
- Good communication regarding unit’s status
- Work on emergency c/s protocols

## Anesthesia Reimbursement

- Antepartum consultation
- Review history
- Explain plan for emergency delivery
- DHMC Level 2 E&M (~$180)
- Intrapartum consultation
- DHMC does not bill
- Monitored Anesthesia Care
- Time and level

## Implementation at DHMC

- Approval by VIC
- Prenatal Care
- Patient Education Brochure
- Sign VBAC Consent
- Have read consent and understand how risks relate to them
-  Read Patient Education Brochure
- Understand what our hospital offers
- That the consent will be reviewed in labor and that they can change their mind
- In Labor
- Consider T&S
- Review VBAC decision, and the patient’s risk factors and their decision and document in MR
- Notify Anesthesia and Pediatrics
- If HR status, consider labor in OR and adequate back up
- Active Labor
- IV
- Continuous EFM

## Conclusions

- Low risk for UR same risk of  emergency c/s as other laboring patients
- Appropriate for community hospitals
- Will rarely impact on OR or life of providers
- Emergency c/s protocols needed everywhere
- Drills
- Evaluation of each procedure
- OB QI Network to track protocol effectiveness
- Women should have a choice

## The VT/NH VBAC Project

## Healthy Baby & Mom

##  NNEPQIN

- Regional Network of Hospitals:  MOU
- Hospitals own their data
- Governed by Consensus
- Mission:  Improve Perinatal Health in NNE
- QI Projects
- VBAC
- Emergency Cesarean Deliveries
- Regional Education Sessions
- Potluck
- Free Speakers
- Bare bones yearly CME meetings
- Data Analysis