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Lecture 10 FETAL DISTRESS. Fetal distress is the term commonly used to describe fetal hypoxia It is a clinical diagnosis made by indirect methods and should be defined as: Hypoxia that may result in fetal damage / death if not reversed or the fetus delivered immediately
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Fetal distress is the term commonly used to describe fetal hypoxia • It is a clinical diagnosis made by indirect methods and should be defined as: • Hypoxia that may result in fetal damage / death if not reversed or the fetus delivered immediately • It includes acute distress and chronic distress DEFINITION
ETIOLOGY Maternal: • poor placental perfusion • hypovolaemia • hypotension • myometrial hypertonus • prolonged labor • excess oxytocin
ETIOLOGY Fetal: • cord compression • oligohydramnios • entanglement • prolapse • pre-existing hypoxia or growth retardation • infection • cardiac
MECHANISM • There are potentially limitless causes for fetal distress, but several key mechanisms are usually involved • Contractions reduce temporarily placental blood flow and can compress the umbilical cord • If a women is in labor longer then this can cause fetal distress via the above mechanism
MECHANISM • Acute distress can be a result of: • placental abruption • prolapse of the umbilical cord (especially with breech presentations) • hypertonic uterine states • use of oxytocin • Hypotension can be caused by either epidural anesthesia or the supine position, which reduces inferior vena cava return of blood to the heart • The decreased blood flow in hypotension can be a cause of fetal distress
SIGNS AND SYMPTOMS • Cardiotocography signs: • Increased / decreased fetal heart (tachycardia and bradycardia), especially during and after a contraction decreased varibility in the fetal heart rate • Abnormal fetal heart rate (< 120 or > 160 bpm) • A normal fetal heart rate may slow during a contraction but usually recovers to normal as soon as the uterus relaxes • A very slow fetal heart rate in the absence of contractions or persisting after contractions is suggestive of fetal distress
SIGNS AND SYMPTOMS • A rapid fetal heart rate may be a response to: • maternal fever • drugs • hypertension • amnionitis • In the absence of a rapid maternal heart rate, a rapid fetal heart rate = a sign of fetal distress • For a diagnosis of fetal distress to be made, one or more of the following must be present: • persistent severe variable deceleration • persistent and non-remediable late declarations • persistent severe bradycardia
SIGNS AND SYMPTOMS • Amniotic fluid is contaminated by meconium • There are 3 degrees about contaminated • I - slight contamination • The color of the amniotic fluid = slight green • II-mild contamination • Color of the amniotic fluid = dark green • III - severe contamination • Color of the amniotic fluid is dark yellow. • If the amniotic fluid is severely contamination, it suggests the, fetal distress - it must be managed as soon as possible
SIGNS AND SYMPTOMS • Decreased fetal movement felt by the mother • Biochemical signs - assessed by collecting a small sample of baby‘s blood from a scalp prick through the open cervix in labor: • Fetal acidosis elevated fetal blood lactate levels • A fetal scalp pH < 7.2 , Po2 >60mmHg suggests fetal distress
SIGNS AND SYMPTOMS • Decreased or disappear fetal movement: • < 10 times per 12 hours is regarded as decreased • With the first effect of hypoxia, the fetal movement is increased • If the hypoxia persists, the fetal movement is decreased, and may disappear • If the fetal movement lost, the fetal heart beat will be disappearing within 24 hours Cautions: Dangerous for the fetus if the fetal movement disappear. Management immediately!!
SIGNS AND SYMPTOMS • Abnormal cardiotocography signs: • Slow fetal heart rate(<120bpm) or rapid fetal heart rate (>180bpm) last more than 10 min in the absence of contractions is suggestive of fetal distress • The fetal heart rate > 160 bpm , especially > 180 bpm, it suggests early hypoxia, unless the maternal heart rate is faster
SIGNS AND SYMPTOMS • FHR < 120bpm, typically less than 100bpm • It is very danger for fetus • The fetal heart rate normally show continuous minor variations, with a range of about 5 bpm, loss of base line variability implies that the cardiac reflexes are impaired, either from the effect of hypoxia or of drugs such as valium • It may be serious
SIGNS AND SYMPTOMS • Early deceleration: with each contraction the rate often slows, but it returns to normal soon after removal of the stress • The early deceleration in the heart rate start within 30 seconds of the onset of the contraction and return rapidly to the baseline rate • It is not of serious significance as a rule and indicate that while the fetus is undergoing some stress the cardiac control mechanisms are responding normally
SIGNS AND SYMPTOMS • Variable deceleration: no consistent relationship with uterine contraction. • It is sometimes caused by compression of the umbilical cord between the uterus and the fetal body, or because it is looped round some part of the fetus • Provided that it does not persist for more than a few minutes it may have little significance, but persistence for more than 15 minutes would call for treatment
SIGNS AND SYMPTOMS • The most serious pattern of heart rate changes is fetal bradycardia with loss of baseline variability and late decelerations • Decrease (defined as onset of deceleration to nadir =30 seconds) and return to baseline FHR associated with a uterine contraction. • The deceleration is delayed in timing, with the nadir of the deceleration occurring after the peak on the contraction
BIOPHYSICAL PROFILE • Biophysical Profile: • Amniotic Fluid Volume Normal = 2 Points • Non-Stress Test Result Positive = 2 Points • Fetal Breathing Movements Active = 2 Points • Fetal Extremity/Trunk Movements Active = 2 Points • Fetal Movements Active= 2 Points • If Biophysical Profile scores < 4 suggest fetal distress • Placental Insufficiency: Low estriol levels, E3 in urine < 10mg/24h
TREATMENT • Reposition patient: left-side-lying position • Administer oxygen by mask • Perform vaginal examination to check for prolapsed cord • Ensure that qualified personnel are in attendance for resuscitation and care of the newborn • Note: each institution shall define in writing the term qualified personnel for resuscitation and care of the newborn
TREATMENT • Each of the following actions should be performed and documented prior to starting a Cesarean section for fetal distress: • Perform vaginal exam to rule out imminent vaginal delivery • Initiate preoperative routines • Monitor fetal heart tones (by continuous fetal monitoring or by auscultation) immediately prior to preparation of the abdomen
TREATMENT • Ensure that qualified personnel are in attendance for resuscitation and care of the newborn (each institution shall define in writing the term qualified personnel for resuscitation and care of the newborn) • STOP using oxytocin ! • Oxytocin can strengthen the contraction of uterine which affects the baby's heart rate
DEFINITIONS MUST GRASPED • Baseline FHR: • approximate mean FHR rounded to increments of 5 bpm during a 10-minute segment, excluding periodic or episodic changes, periods of marked FHR variability, and segments of the baseline that differ by > 25 bpm • In any 10-minute window, the minimum baseline duration must be at least 2 minutes or the baseline for that period is indeterminate
DEFINITIONS MUST GRASPED • Baseline FHR variability: • Fluctuations in the baseline FHR =2 cycles / min • These fluctuations are irregular in amplitude and frequency, and are visually quantitated as the amplitude of the peak to the trough in beats per minute as follows: • amplitude range undetectable, absent FHR variability; • amplitude range greater than undetectable but = 5 bpm, minimal FHR variability; • amplitude range 6 bpm to 25 bpm, moderate FHR variability; • amplitude range >25 bpm, marked FHR variability
DEFINITIONS MUST GRASPED • Bradycardia: • a baseline FHR <120 bpm • Tachycardia: • a baseline FHR >160 bpm
DEFINITIONS MUST GRASPED • Early deceleration: • a visually-apparent, gradual decrease (defined as onset of deceleration to nadir =30 seconds) and return to baseline FHR associated with a uterine contraction • The decrease is calculated from the most recently determined portion of the baseline • It is coincident in timing with the nadir of the deceleration occurring at the same time as the peak of the contraction • In most cases the onset, nadir, and recovery of the deceleration are coincident with the beginning, peak, and ending of the contraction, respectively
DEFINITIONS MUST GRASPED • Variable deceleration: • a visually-apparent, abrupt decrease in FHR below the baseline • The decrease is calculated from the most recently determined portion of the baseline • The decrease in FHR below the baseline is =15 bpm, lasting =15 seconds and =2 minutes from onset to return to baseline
DEFINITIONS MUST GRASPED • Late deceleration: • a visually-apparent, gradual decrease (defined as onset of deceleration to nadir = 30 seconds) and return to baseline FHR associated with a uterine contraction • The decrease is calculated from the most recently determined portion of the baseline • The deceleration is delayed in timing, with the nadir of the deceleration occurring after the peak on the contraction
INTRAUTERINE FETAL DEATH (IUFD) • DEFINITION: • dead fetuses or newborns weighing > 500g or > 20 wks gestation 4.5/ 1000 total births • DIAGNOSIS: • Absence of uterine growth • Serial ß-hcg Loss of fetal movement Absence of fetal heart Disappearance of the signs & symptoms of pregnancy X-ray Spalding sign Robert’s sign U/S 100% accurate Dx
CAUSES OF IUFD • Maternal 5-10% • Antiphospholipid antibody • DM • HPT • Trauma • Abnormal labor • Sepsis • Acidosis/ Hypoxia • Uterine rupture • Postterm pregnancy • Drugs • Thrombophilia • Cyanotic heart disease • Epilepsy • Severe anemia • Unexplained 25-35% • Fetal causes 25-40% • Chromosomal anomalies • Birth defects • Non immune hydrops • Infections • Placental 25-35% • Abruption • Cord accidents • Placental insufficiency • Intrapartum asphyxia • P Previa • Twin to twin transfusion S • Chrioamnionitis
A systematic approach to fetal death is valuable in determining the etiology • B-Maternal History • I-Maternal medical conditions • VTE/ PE • DM • HPT • Thrombophilia • SLE • Autoimmune disease • Severe Anemia • Epilepsy • Consanguinity • Heart disease • II-Past OB Hx • Baby with congenital anomaly / hereditary condition • IUGR • Gestational HPT with adverse sequele • Placental abruption • IUFD • Recurrent abortions 1-HISTORY • A-Family history • Recurrent abortions • VTE/ PE • Congenital anomalies • Abnormal karyptype • Hereditary conditions • Developmental delay
1-HISTORY • Specific fetal conditions • Nonimmune hydrops • IUGR • Infections • Congenital anomalies • Chromosomal abnormalities • Complications of multiple gestation • Current Pregnancy Hx • Maternal age • Gestational age at fetal death • HPT • DM/ Gestational D • Smooking , alcohol, or drug abuse • Abdominal trauma • Cholestasis • Placental abruption • PROM or prelabor SROM • Placental or cord complications • Large or small placenta • Hematoma • Edema • Large infarcts • Abnormalities in structure , length or insertion of the umbilical cord • Cord prolapse • Cord knots • Placental tumors
2-EVALUATION OF STILL BORN INFANTS • Infant description • Malformation • Skin staining • Degree of maceration • Color-pale ,plethoric • Umbilical cord • Prolapse • Entanglement-neck, arms, • legs • Hematoma or stricture • Number of vessels • Length • Amniotic fluid • Color-meconium, blood • Volume • Placenta • Weight • Staining • Adherent clots • Structural abnormality • Velamentous insertion • Edema/hydropic changes • Membranes • Stained • Thickening
3-INVESTIGATIONS • Fetal investigations • Fetal autopsy • Karyotype • (specimen taken from cord • blood, intracardiac blood, • body fluid, skin, spleen, • placental wedge, or amniotic • fluid) • Fetography • Radiography • Maternal investigations • CBC • Bl Gp & antibody screen • HB A1 C • Kleihauer Batke test • Serological screening for Rubella • CMV, Toxo, Sphylis, Herpes & • Parovirus • Karyotyping of both parents (RFL, • Baby with malformation • Hb electrophorersis • Antiplatelet anbin tibodies • Throbophilia screening (antithrombin • Protein C & S , factor IV leiden, • Factor II mutation, , lupus anticoagulant, • anticardolipin antibodies) • DIC • Placental investigations • Chorionocity of placenta in • twins • Cord thrombosis or knots • Infarcts, thrombosis, abruption • Vascular malformations • Signs of infection • Bacterial culture for E.coli, • Listeria, gp B strpt.
IUFD COMPLICATIONS • Hypofibrinogenemia 4-5 wks after IUFD • Coagulation studies must be started 2 wks after IUFD • Delivery by 4 wks or if fibrinogen < 200mg/ml
PSYCHOLOGICAL ASPECT & COUNSELING • A traumatic event • Post-partum depression • Anxiety • Psychotherapy • Recurrence 0-8% depending on the cause of IUFD