Hot Topics in Obstetrics Malpractice Claims

Michael G. Ross, MD, MPH Harbor-UCLA Med Ctr Geffen School of Medicine at UCLA

• New Updates with Implications – Antenatal Corticosteroids – Planned Home Birth – Magnesium Sulfate Use • Challenging Theories – The Acidosis Paradox – Fetal Head Compression – Maternal Forces in Shoulder Dystocia and Brachial Plexus Injury Antenatal Corticosteroid Therapy for Fetal Lung Maturation

• ACOG Committee Opinion 677, Oct 2016

• A single course of betamethasone is recommended for pregnant women between 34 0/7 weeks and 36 6/7 weeks of gestation at risk of preterm birth within 7 days, and who have not received a previous course of antenatal corticosteroids Planned Home Birth

• ACOG Committee Opinion 669, August 2016

• ~ 1 % of US deliveries occur at home

• Women inquiring about planned home birth should be informed of its risks and benefits based on recent evidence. Specifically, they should be informed that although planned home birth is associated with fewer maternal interventions than planned hospital birth, it also is associated with a more than twofold increased risk of perinatal death (1–2 in 1,000) and a threefold increased risk of neonatal seizures or serious neurologic dysfunction (0.4–0.6 in 1,000). Magnesium Sulfate Use in Obstetrics

• ACOG Committee Opinion 652, Jan 2016

• The American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine continue to support the short-term (usually less than 48 hours) use of magnesium sulfate for … fetal neuroprotection before anticipated early preterm (less than 32 weeks of gestation) delivery Challenging Theories

–The Acidosis Paradox –Fetal Head Compression –Maternal Forces in Shoulder Dystocia and Brachial Plexus Injury There“Acidosis is no Paradox”

• Hermansen, 2003: – “asphyxial brain injury without coincident acidemia” • Schifrin, 2006: Head compression may cause brain injury without acidosis

Medicolegal implications: – Do not need severe acidemia to result in asphyxial injury Acidosis Paradox Fallacies

• “Infants born with brain injury but normal pH have failed to initiate compensatory mechanisms associated with beneficial acidemia” • Beneficial acidosis responses – Bohr effect: increase oxygen dissociation to tissues – Increase cerebral blood flow – Decrease cerebral metabolism No data to suggest that these do not happen Acidosis Paradox Fallacies

• Wash Out: “Lactate accumulates in tissues and does not circulate until resucitation and recovery” • Lactate: product of anaerobic metabolism – Cleared out of cell by lactate transporter – Fetal heart rate and cardiac output continue despite prolonged bradycardia No data in fetuses or adults to suggest a Wash Out phenomenon What Explains Wash Out?

• Measured umbilical vein only • Difficult newborn transition: – Increases Acidosis • CPR • Failed intubation, pneumothorax, sepsis What does Hermansen reference? “Do not need severe acidosis” • Ruth and Raivio, 1988 – “All five infants with HIE had both a low APGAR score and acidosis at birth” • Korst et al, 1997 pH<7.0 – “..first arterial blood pH was recorded” – mean time of newborn gas was 50 min What does Hermansen reference?

• Hankins et al, 2002 – 75% of asphyxia cases had BD>12 • 25% of cases had BD < 12 – “these findings are entirely consistent with… …partial recovery of the acute metabolic injury” • Dennis et al, 1989 – 10 nonacidotic babies with APGAR<3 showed significant deficits in some areas – Likely result of pre-existing injury Acute Intrapartum Asphyxia resulting in Brain Damage must have accompanying Acidosis

• Interpret both umbilical artery and vein values • If newborn gas, must use BD not pH

• BDECF (vs BDblood) in high pCO2 • 80% of cerebral palsy unrelated to labor – Preexisting conditions Challenging Theories

–The Acidosis Paradox –Fetal Head Compression –Maternal Forces in Shoulder Dystocia and Brachial Plexus Injury Can Head Compression Cause Asphyxia with or without Acidosis? Evolution of Human Pelvis Pelvis and Labor Comparison

Rosenberg and Trevathan (2002); based on Shultz (1949) Head Compression During Labor

Increased Amniotic Pressure due to contractions

Force against the bony pelvis

Effect of FHT decelerations

Cushing Response Can Head Compression Cause Asphyxia without Acidosis?

• Schifrin and Ater, 2006 • “Numerous pitfalls await those who attempt to define the severity of intrapartum asphyxia on the basis of an umbilical pH” • “Excessive uterine activity, especially when accompanied by relentless bearing-down of the mother during the second stage, predisposes to fetal embarrassment”

• What is the data ???

• Current Opinion in Obstetrics and Gynecology, 2006 Amniotic Pressure and Fetal Head Pressure during Contractions

Fetal Head Pressure

Amniotic Pressure

AmnioticHuman Pressure Fetus

Eskes et al , 1975 What is the Arterial Pressure during Contractions • Fetal head pressure and blood pressure parallel increase in amniotic fluid pressure

Sheep Fetus Arterial Pressure

Venous Pressure

Amniotic Pressure

Shields and Brace, 1994 Sheep: Increase in Cerebral Pressure: Simulated Pressure Against Pelvic Bone

• Chronically catheterized fetal lamb • Increase intracranial pressure with infusion into lateral ventricle – ICP increase to arterial pressure 41 mmHg • Cerebral blood flow maintained by peripheral vasoconstriction and increased blood pressure – Decreased renal, GI, skin flow • Cerebral O2 uptake maintained – Increased fractional O2 extraction – Cushing Response

Harris et al, 1988, 1997 Sheep: Effect of Cephalic Pressure on Fetal Cerebral Blood Flow

• Acutely catheterized fetal lamb • Increase cephalic pressure with inflatable cuff – ICP increase to 200 mmHg (point of bradycardia) • Cerebral blood flow decreased by 95% • Limitations – Is 200 mmHg physiologic in sheep

O’Brien et al, 1984 Human Studies: Moderate Fetal Bradycardia due to Head Compression

• Moderate bradycardia (100-119 bpm) • No loss of variability • Associated with transverse/posterior head position and increased uterine activity

• Not relieved by oxygen or maternal position • Alleviated by rotation of the vertex • No adverse fetal effects

• Young and Weinstein, AJOG, 1976 Effect of Fetal Head Compression on Fetal Cerebral Function as Measured by the Fetal EEG

• African Women: 25 Primigravida • Head compression: – Failure to progress – Increased moulding – Failure to descend • No impact of severe head compression on Fetal EEG – As compared to adverse effect of fetal acidemia

• Wilson et al, 1979 Head Compression Effects ?

• Humans have uniquely tight bony pelvis – ? Adaptive human fetal response – Sheep may not be optimal model • Caput, Moulding  Cone head • ACOG: extended second stage • Conclusion: – No Clinically Proven Adverse Effects of Head Compression Challenging Theories

–The Acidosis Paradox –Fetal Head Compression –Maternal Forces in Shoulder Dystocia and Brachial Plexus Injury Shoulder Dystocia and Erb’s Palsy: Role of Maternal Forces Maneuvers

• McRoberts • Suprapubic Pressure • Rotation of Shoulders: Woods Screw, Rubins I, II • Delivery of Posterior Arm • Episiotomy • General Anesthesia • Intentional Fracture of Clavicle • Zavanelli Pull Harder !!! McRoberts Maneuver Suprapubic pressure What Actually causes BP injury?

• Delivery and Turtle Sign • Maternal Pushing – McRoberts • Individual Variability: BP anatomy • Physician traction forces ?? Nerve stretch with Delivery and Turtle Sign Nerve Stretch with Maternal Pushing What is the Data?

• Delivery and Turtle Sign • Maternal Pushing – McRoberts • Individual Variability: BP anatomy

Contact Pressure at Impaction Site nearly 10 fold Greater with Pushing than with Clinician Traction

• Multigravid Pushing 191 kPa • Primigravid Pushing 203 kPa • Clinician Traction 23 kPa

Contact Force 2 x greater with Maternal Pushing than Clinician Traction

Contact Force • Maternal Pushing 100 - 400 N 147 – 272 N • Clinician Traction 50 -100 N 107 - 127 N

More Force and More BP Stretching with Maternal Pushing than clinician traction

• Delivery with Maternal Forces: 125 N – BP Stretching: 15.7% • Delivery with Physician Traction: 75N – BP Stretching: 14% • Reduced Stretch with McRoberts

Maternal Pushing Markedly increases Intrauterine Pressure

• Maternal Pushing Increases Intrauterine Pressure by 62% • Force of Pushing (Valsalva Index) Increases in Relation to Maternal BMI (2 x BMI)

Combined Endogenous Effects of Contraction Force, Maternal Pushing Force, and McRoberts Position

• Maternal Valsalva Increased Expulsive Force by 32% • McRoberts Position Doubled (2x) Expulsive Force Nerve stretch with Contractions, Turtle sign, and Maternal Pushing / McRoberts Do Physicians Pull too Hard?

Vacuum-assisted vaginal delivery simulation--quantitation of subjective measures of traction and detachment forces. Eskander R1, Beall M, Ross MG. 1Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA, Torrance, CA 90502, USA. J Matern Fetal Neonatal Med. 2012 Oct;25(10):2039-41. doi: 10.3109/14767058.2012.675374. Epub 2012 Apr 18. Abstract OBJECTIVE: Excessive traction has been alleged as the cause of newborn complications associated with vacuum delivery. We sought to quantify subjective levels of physician vacuum traction in a simulated obstetric delivery model, dependent upon level of training. METHODS: Three groups of physicians, based on training level applied traction (minimal, average, maximal) on a pre- applied vacuum model and forces were continually recorded. Detachment force was recorded with traction in both the pelvic axis and at an oblique angle. RESULTS: Quantified traction force increased from subjective minimal to average to maximal pulls. Within each level, there were no differences between the groups in the average traction force. Detachment force was significantly less when traction was applied at an oblique angle as opposed to the pelvic axis (11.1 ± 0.3 vs 12.2 ± 0.3 kg). CONCLUSION: Providers appear to be good judges of the force being applied, as a clear escalation in force is noted with minimal, average and maximal force pulls. There appears to be a relatively short learning curve for use of the vacuum, as junior residents' applied force was not different from those of more experienced practitioners. Using the KIWI device, detachment force is lower when traction is applied at an oblique angle. Traction Forces on Fetal Head Moderate Traction is Moderate Traction

• Physicians are Excellent Judge of Traction Force from Mild to Moderate to Severe

Vacuum-assisted vaginal delivery simulation--quantitation of subjective measures of traction and detachment forces. Eskander R1, Beall M, Ross MG. 1Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA, Torrance, CA 90502, USA. J Matern Fetal Neonatal Med. 2012 Oct;25(10):2039-41. doi: 10.3109/14767058.2012.675374. Epub 2012 Apr 18. Abstract OBJECTIVE: Excessive traction has been alleged as the cause of newborn complications associated with vacuum delivery. We sought to quantify subjective levels of physician vacuum traction in a simulated obstetric delivery model, dependent upon level of training. METHODS: Three groups of physicians, based on training level applied traction (minimal, average, maximal) on a pre- applied vacuum model and forces were continually recorded. Detachment force was recorded with traction in both the pelvic axis and at an oblique angle. RESULTS: Quantified traction force increased from subjective minimal to average to maximal pulls. Within each level, there were no differences between the groups in the average traction force. Detachment force was significantly less when traction was applied at an oblique angle as opposed to the pelvic axis (11.1 ± 0.3 vs 12.2 ± 0.3 kg). CONCLUSION: Providers appear to be good judges of the force being applied, as a clear escalation in force is noted with minimal, average and maximal force pulls. There appears to be a relatively short learning curve for use of the vacuum, as junior residents' applied force was not different from those of more experienced practitioners. Using the KIWI device, detachment force is lower when traction is applied at an oblique angle. Variations in Brachial Plexus Anatomy: Susceptibility to Injury J Brachial Plex Peripher Nerve Inj. 2007 Oct 3;2:21.

Variations in brachial plexus and the relationship of median nerve with the axillary artery: a case report. Singhal S1, Rao VV, Ravindranath R J Brachial Plex Peripher Nerve Inj. 2011 Jun 7;6:1. doi: 10.1186/1749-7221-6-1. Clin Anat. 2010 Mar;23(2):210-5. doi: 10.1002/ca.20927. A quantitative analysis of variability in brachial plexus anatomy. Variations in branching of the posterior cord of brachial

Fetty LK1, Shea J, Toussaint CP, McNulty JA plexus in a Kenyan population. Muthoka JM1, Sinkeet SR, Shahbal SH, Matakwa LC, Ogeng'o JA Anatomical study of the communicating branches of cords of the brachial plexus and their clinical implications.

Song ZF1, Sun MM, Wu ZY, Lv HZ, Xia CL.  1Boxi Institute of Clinical Anatomy & Lab of Aging and Nervous Diseases, Medical College of Soochow University, Suzhou 215123, China; Th General Clin Anat. 2011 Mar;24(2):168-78. doi: 10.1002/ca.21095. Epub 2011 Jan 25. Hospital of Xingtai Mining Industry Bloc, Xingtai 054000, China. Patterns of motor branching of the musculocutaneous nerve in human fetuses and clinical significance. Kervancioglu P1, Orhan M, Kilinc N Natural Forces of Labor and Delivery Are Primary Cause of BP Injury, With and Without Shoulder Dystocia

• Contraction Force • Turtle Sign Stretch • Maternal Pushing – McRoberts Increase of Pushing Force • Variations in Brachial Plexus Anatomy and Susceptibility

• Despite world-wide efforts to reduce Brachial Plexus Injury, 20% of shoulder dystocia result in initial or permanent injury Simply the Occurrence of BP Injury, whether temporary or permanent, does not indicate clinician negligence Topics