# Presentation: 409741

## THE OB-PEDS INTERFACE: “GOT ISSUES?”

- George J. Gilson, M.D.
- Alaska Native Medical Center
- September 2005

## Slide 2

## THE OB-PEDS INTERFACEOBJECTIVES

- THE OB-PEDS INTERFACEOBJECTIVES

- _PPROM:_  What gestational age to deliver?

- _GBS:_ Where does controversy remain?

- _Antenatal Corticosteroids:_ Should you repeat the      				  course?

- _Meconium:_ To suction or not to suction?

- _Oxygen:_ Does it really help resuscitation?

- _Apgars:_ Will the lawyers be in touch?

## PPROM: What gestational age to deliver? 

- The longer the latent period, the more mature the baby, and the less time and effort it will require in the nursery.
- 		_Versus_
- The longer the latent period, the more likely that infection will occur, and that the baby will have a longer LOS.

## PPROM: When to deliver?

- _Mercer (1993) - RCT @ 32-36 wks (n=93)_
- 	_Management_:      _Expectant_  vs.  _active_
- Latency (hrs)            36                  14*
- Chorio (%)                28                  11*
- Suspect sepsis(%)   60                   28*
- Confirmed sepsis     4.3                  6.8
- Antibx tx (%)             79                  35*
- Home w/mom(%)       4                   30*

- _What does the evidence show??_

## PPROM: When to deliverIncidence of IRDS

- 28 weeks			65%
- 30 wks				50%
- 32 weeks			40%
- 34 weeks			13%*
- 35 weeks			  7%*
- 36 weeks			<1%*
- * majority needed suppl O2, 1.3% ventilator

## PPROM: When to deliver?

- _As-Sanie (2003)-CCS @34-36 wks (n=1544)_
- Non-pulmonary morbidity if no IRDS?
-                                 _IRDS (n=75)_    _Controls_
- NICU admit (%)      	 100                 36*
- PDA                         	  8.1                 1.3
- IVH                             	  6.8                 1.3
- NEC                                 0                     0
- Confirmed sepsis             0                     0

## PPROM: When to deliver?

- _As-Sanie (2003)-CCS@34-36 wks (n=1544)_
- Non-pulmonary morbidity if no IRDS?
-                             _IRDS (n=75)_      _Controls_
- Hyperbili-UVL(%)     57                   29*
- Hypoglyc-OGT         45                   21*
- Hypothermia             98                  57*
- Apnea/brady             30                    5*

## PPROM: When to deliver?

- _(3) smaller studies: (n=485) @ 32-36 wks_
- _Expectant vs. active management:_
- More chorio and longer maternal LOS
- More sepsis and suspected sepsis
- Latency: 10%>48 hrs, 2.5%>7days
- Incidence of IRDS: 1.5-13%
- Cut off for IRDS and infant LOS: 34 wks

## PPROM: When to deliver?

- _Leiman (2005) –retrospective (n=430):_
- Latency: 3.3 _+_ 6.8 days overall
- No improvement in either major or minor neonatal morbidity after 34 weeks
- Both maternal and neonatal LOS longer after 34 weeks with expectant management

## PPROM: When to deliver?

- _ __At 34 weeks (n=58):_
- IRDS			5.2%
- IVH			1.7%
- NEC		   	   0
- Sepsis			1.7%
- Hyperbili-UVL	 72%
- Hypoglyc-OGT	8.6%
- LOS			8.1_+_5.8 days

## PPROM: When to deliver?

*Lieman. Preterm PROM and Neonatal Morbidity. Obstet Gynecol 2005.*

## Slide 13

## GBS: Remaining Controversies

- _Alaska GBS EONS 2000-2004:_
- 21 cases (incidence: 0.42/1000)
- 8/21 mothers _had an indication for IAP_:
- 3 preventable (2 no abx, 1 wrong abx)
- 13/21 mothers _did not have_ an indication:
- 9 preventable (not screened...)
- 5 mothers delivered in <4 hours...

## GBS Controversies:IAP for elective cesarean?

- _NO:_
- _Ramus et al_ (1998) n=3590 elective C/S
- 20% carrier rate
- Attack rate = 0 (95% CI-0.0-0.7%)
- No benefits to IAP if NIL and no ROM

## GBS Controversies:How about PPROM and PTL?

- _YES (initially):_
- Culture and treat x 48 hrs
- If GBS (-): stop abx, no IAP when in labor
- If GBS (+): may continue abx x 5-7 d, but will need IAP when in labor
- If GBS (-) and more than 5 wks until labor, repeat the culture and tx if now (+) (5%+)

## GBS Controversies:What about PCN allergy?

- 15% of GBS are resistant to clindamycin
- 21% of GBS are resistant to erythromycin
- Always request sensitivies if allergic
- Cefazolin if no anaphylaxis
- Vancomycin if anaphylaxis
- To date no incidence of resistant GBS

## GBS Controversies:Indications for IAP

- Prior GBS affected infant
- GBS bacteriuria during this pregnancy
- Positve GBS culture 35-37 wks
- Unknown GBS status AND:
- Delivery <37 wks
- ROM >18 hrs
- Temp >100.4  in labor

## GBS Controversies:IAP not indicated

- GBS (+) in a prior pregnancy
- Planned cesarean (NIL, I-BOW)
- GBS (-) during at 35-37 wks this pg (despite having a risk factor)

## GBS: Newborn Management after IAP

- _Maternal chorio or signs of NN sepsis_:
- Full diagnostic evaluation:
-    	 -CBC, BC, CXR, LP
- _GA <35 wks –or- IAP for <4 hrs_:
-   	 Limited diagnostic evaluation:
-     -CBC, BC, 48 hr obs
- _IAP for >4 hrs_:
- 	No eval, no tx, 48 hr (24 hr?) observation

## Alaska Parking Violation?

**Alaska Parking Violation?**

## Antenatal Corticosteroids:Repeated Courses: Is More Better?

-      _Single Course_              _OR_         _CI_
- Reduction in IRDS	0.49    (.41-.60)
- “  “ IRDS after 7 d*	0.69    (.50-.94)
- “  “ Neonatal death	0.59	   (.47-.75)
- “  “ IVH				0.45    (.21-.97)
- “  “ NEC				0.37	   (.17-.69)
- “  “ Neuro abn		0.61    (.34-1.08)

## Steroids: Mechanism of Action

**Steroids: Mechanism of Action**

## Antenatal Corticosteroids:Repeat Courses: Is More Better?

- _Meta-analysis of 8 observational studies:_
- _Aghajafari – 2001:_  n=1682 (24-34 wks):
- Reduction in IRDS		OR=.79*
- Reduction in PDA			OR=.56*
- No difference in IVH, NEC, sepsis, NND
- Trend to increased BPD	OR=1.30
- Selection bias

## Antenatal Corticosteroids:Repeated Courses: Is More Better?

- _Retrospective studies of multiple courses:_
- _Thorp (2002):_ n=14,338 (23-34 wks)
- 	Decrease in BWt (63g) and HC (3.1mm)
- _French (2004):_ n=541 (23-32 wks6 y/o)
- 	Decrease in IVH and PVL:      OR=.40*
- 	Decrease in CP (n=22):          OR=.31*
- 	Increase in ADD (n=31):         OR=2.39

## Antenatal Corticosteroids:Repeated Courses: Is more better?

- 3 RCT:  n=561
- _Guinn (2001)_: n=502 (23-32 wks)
- No difference in composite outcome of IRDS, BPD, IVH, PVL, NEC, NND
- OR=.80 (CI: .59-1.10)
- No difference in BWt or HC
- Insufficient evidence to recommend

## Antenatal Corticosteroids:Repeated Courses: Is More Better?

- _ACOG Committee Opinion – 2001:_
- Single course between 24-34 wks SOC
- Insufficient data regarding safety and efficacy to recommend repeated courses
- More RCT encouraged
- Currently 3 in progress

## Slide 28

## Meconium Happens!

- Meconium happens in 7-22% of all births
- Meconium happens >30% of postterm
- MAS occurs in 2/1000 births (8% postterm)
- Meconium is found below the cords in 21-58% of births thru mec stained fluid
- Only 5-10% of infants with mec below the cords will develop MAS

## Meconium HappensWhat are the risk factors for MAS?

- NOT correlated w/ decels, low pH, 5 min Apgar or other markers of acute hypoxia
- IS correlated w/ oligo, elevated cord EPO, postmaturity, muscularization of the pulmonary arterioles (chronic hypoxia)
- Fetal breathing vs. fetal gasping (>pCO2)
- MAS is the result of in-utero gasping

## Meconium Happens Is MAS Preventable?

- _AMNIOINFUSION:_  YES
- Meta-analysis: 13 studies (n=2000):
- Reduced MAS  (8.5 vs 2.5%)       OR=.30*
-  “ mec below cords (23% vs 5%)  OR=.18*
-  “ acidemia  (25% vs 12%)            OR=.42*
-  “ cesarean    (19% vs 24%)          OR=.74

## Meconium HappensIs MAS Preventable?

- _Amnioinfusion:_ NO
- _Fraser_ – NEJM Sept 2005
- International multi-center RCT (n=1998)
- _Amnio:_ 4.5% MAS, 0.5% NND, 32% C/S
- _Control:_ 3.1% MAS, 0.5% NND, 29% C/S
- Does a big RCT trump meta-analysis?

## Meconium HappensIs MAS Preventable?

- _ORO-PHARYNGEAL SUCTIONING:_   “MAYBE”
- _YES_: Wiswell (2000) - RCT - n=2094
- 	Reduced MAS (8.5 vs. 2.7%)
- _NO_: Vain (2004) – RCT - n=2514
- 	No reduction in MAS             (4 vs 3.8%)
- 	 “       “              mech vent     (2 vs 1%)
- 	 “       “              NN death      (0.7 vs 0.3%)

## Meconium HappensIs MAS Preventable?

-   _Tracheal suctioning:_  NO
- Meta-analysis of 4 RCT (2000)  n=2884
- 	No decrease in MAS          (2.5 vs 2.0%)
- 	No decrease in NN death   (0.3 vs 0.1%)
-    No decrease w/pulm prob  (3.8 vs.4.5%)
- 3.8% incidence of stridor, bradycardia, etc in the intubated infants....

## Meconium HappensRecommendations

- _Amnioinfusion_ in the presence of meconium _and_ decels may be helpful
- _Oropharyngeal suctioning_ may be helpful, and is not harmful
- _Tracheal suctioning_ is not indicated in vigorous infants, and may or may not be helpful in depressed infants
- (_Inducing labor at 41 wks_ is probably the biggest factor in reducing MAS and PNM as meconium is probably aspirated before presentation...)
-    “THE ENEMY OF GOOD IS BETTER!”

## scenery

## Perinatal ResuscitationIs Room Air or 100% O2 Best?

- Does O2 actually help?
- Might O2 actually be harmful?
- Availability and cost in rural settings
- Some thoughts about:
- pO2
- O2 saturation (SaO2)
- O2 content (CaO2)
- O2 delivery (DO2)

## Perinatal ResuscitationRoom Air or 100% O2?

- pO2 = concentration of O2 x tot pressure
- SaO2 = O2 combined w/ Hb x 100
- CaO2 = 1.39 x Hb x O2 sat/100 +.003 pO2
- DO2 = CO (Hb x O2 sat)
-             CO = HR x SV
- Ventilation responds to pO2
- O2 delivery depends on CaO2

## Maternal-Fetal pO2 Relationship

## Maternal-Fetal O2 Saturation Relation

## O2 Content = Hb x O2 Saturation

**HB = 20**

**HB = 15**

**HB = 10**

**100**

**50**

**0**

**PO2 (mmHg)**

**O2 Concentration (ml/100ml)**

**O2 Sat**

## Maternal-Fetal O2 Content Relation

## In-Utero ResuscitationRoom Air or 100 O2? 

- _Cochrane – 2005_
- No trials of O2 for fetal distress
- 2 RCT of prophylactic O2 in normal labor
- Abnormal cord pH (<7.2) more frequent in the O2 group (RR=3.51, CI 1.34-9.19)
- O2 may cause placental vasoconstriction
- _Conclusion_: the evidence does not support the use of O2 in labor....

## Neonatal ResuscitationRoom Air or 100% O2?

- _Davis (2004)  meta-analysis (n=1302):_
- Infants still cyanotic and bradycardic switched to O2 at 90 sec (intent to tx)
- Room air group: decreased NN mortality RR=0.71 (CI .54-.94)
- No difference in incidence of HIE
- No difference in neuro disability at 24 mos
- _Conclusions_: insufficient evidence....

## Neonatal ResuscitationRoom Air or 100% O2?

- _Saugstad (2005)_ meta-analysis (n=881):
- Neonatal mortality favors room air: OR=0.57 (CI .42-.78)
- HR at 90 sec, Apgar score at 5 min, and time to 1st breath all significantly better in the room air group
- Hypoxia-reperfusion injury?

## Got Oxygen???

**Got Oxygen???**

## Use and Abuse of the Apgar Score

- Apgar (1952): a scoring system for estimating the probability of newborn survival
- Apgar (1958): use of the scoring system for evaluating the need for newborn resuscitation
- The Apgar score is not intended to be a predictor of neurologic development
- The Apgar score is not intended to be a marker of newborn asphyxia

## Use and Abuse of the Apgar Score

- _AAP and ACOG Statements - 1996_
- _Asphyxia_: a combination of hypoxemia and acidemia in the peripartum period resulting in acute neurologic injury.
- Infants should demonstrate:
- Metabolic or mixed acidemia (pH<7.00)
- Apgar 0-3 at >5 minutes
- CNS sx (sz, coma, hypotonia)
- Multiorgan dysfunction (CV, GI, renal, heme)

## Use and Abuse of the Apgar Score

- _Use of Umbilical Cord Gases_:
-                                    	 _pH_    _pCO2_	_BE_
- Metabolic acidosis       <7.20   <65      >-12
- Respiratory acidosis    <7.20   >65      >-12
- Mixed acidosis	       <7.20   >65      >-12

## Use and Abuse of the Apgar Score

- _Correlation of Apgar<7 at 5’ and pH<7.20_:
- _Thorp (1995)_  (n=1924)
- pH <7.2 in infant w/ Apgar <7 at 5’   14%
- most infants w/ low Apgars have good pH
- pH <7.2 in a “depressed” infant         78%
- low pH is predictive of true depression
- pH <7.2 in a vigorous infant                2%
- there are false positives

## Use and Abuse of the Apgar Score

- _Apgar score and later neurologic disability_:
- _Nelson (1981)_    (n=49,000)
- 	n=99 Apgar 0-3 at 10 min studied at 7 y/o:
- 12% had CP, of whom 11% IQ<50, 6% sz
- 8% other (non-CP) neuro disability
- 80% free of major handicap

## Use and Abuse of the Apgar Score

- _pH and later neurologic disability_:
- _Nagel (1995) n=1614:_
- 30 had pH<7.0 and studied at 3 y/o:
- all went to the NICU, 28 survived
- 10% mild hypotonia
- 3.5% mild developmental delay

## Use and Abuse of the Apgar Score

- _Conclusions_:
- Neither Apgar score nor pH predicts future neurologic outcome well
- If you get out of the NICU w/o a major problem you do pretty well
- Pessimism in counseling parents is unwarranted
- Hopefully the lawyers won’t be in touch...

## Slide 54

## The OB-Peds InterfaceGot More Issues?

- Maternal medications and breast feeding
- Circumcision (should we be doing it?)
- NSAIDs as tocolytics (NN adverse effects?)
- Hypoglycemia in IDDM (best prevention?)
- Tobacco use and neonatal withdrawal
- Early vs. late cord clamping (does it matter?)
- What else??

## How babies’ are REALLY delivered...

***How babies’ are REALLY delivered...***