Ultrasonography in Biophysical Profile
No Results
No Results
processing….
The biophysical profile (BPP) is a noninvasive test that predicts the presence or absence of fetal asphyxia and, ultimately, the risk of fetal death in the antenatal period. [1] When the BPP identifies a compromised fetus, measures can be taken to intervene before progressive metabolic acidosis leads to fetal death. [2, 3, 4, 5, 6, 7]
The BPP combines data from 2 sources (ie, ultrasonographic imaging and fetal heart rate [FHR] monitoring). Dynamic realtime B-mode ultrasonography is used to measure the amniotic fluid volume (AFV) and to observe several types of fetal movement. The FHR is obtained using a pulsed Doppler transducer integrated with a high-speed microprocessor, which provides a continuously updated reading. [8, 9]
Originally described by Manning and colleagues, [10, 11] the BPP has become a standard tool for providing antepartum fetal surveillance. The BPP integrates 5 parameters to yield a biophysical profile score (BPS) and includes (1) the nonstress test (NST), (2) ultrasonographic measurement of the AFV, (3) observation of the presence or absence of fetal breathing movements, (4) gross body movements, and (5) tone. Table 1, below, describes specific criteria for the BPS.
The BPP allows 2 points for each parameter that is present, yielding a maximum score of 10; however, if all of the ultrasonographic variable findings are normal, the FHR variable may be excluded, because no change is made in the predicative accuracy of the BPP by including the FHR (see the graph below). If 1 or more ultrasonographic variable findings are abnormal, the NST should be performed.
A basic principle of antepartum testing is that a more accurate prediction of fetal wellness is achieved in direct proportion to the number of variables considered. The BPP is a clinical tool that integrates levels of dynamic biophysical activities into a usable standard. [12] The BPP allows 2 points for each parameter that is present, yielding a maximum score of 10; however, if all ultrasonographic variables are normal, the FHR variable may be excluded because no change is made in the predictive accuracy of the BPP by including the FHR. If 1 or more ultrasonographic variables are abnormal, the NST should be performed. [13]
Table 1. Criteria for Coding Fetal Biophysical Variables as Normal or Abnormal (Open Table in a new window)
Biophysical
Variable
Normal
(Score = 2)
Abnormal
(Score = 0)
Fetal breathing movements*
1 or more episodes of ≥20 s within 30 min
Absent or no episode of ≥20 s within 30 min
Gross body movements
2 or more discrete body/ limb movements within 30 min (episodes of active continuous movement considered as a single movement)
< 2 episodes of body/limb movements within 30 min
Fetal tone
1 or more episodes of active extension with return to flexion of fetal limb(s) or trunk (opening and closing of hand considered normal tone)
Slow extension with return to partial flexion, movement of limb in full extension, absent fetal movement, or partially open fetal hand
Reactive FHR
2 or more episodes of acceleration of ≥15 beats per minute (bpm) and of >15 s associated with fetal movement within 20 min
1 or more episodes of acceleration of fetal heart rate or acceleration of < 15 bpm within 20 min
Qualitative AFV
1 or more pockets of fluid measuring ≥2 cm in vertical axis
Either no pockets or largest pocket < 2 cm in vertical axis
*Note: The current clinical management guidelines from the American College of Obstetrics and Gynecology maintain the original findings from Manning et al in 1987. [13] These include the following:
Fetal breathing movements should include 1 or more episodes of rhythmic fetal breathing for at least 30 s or more in 30 min. Manning et al’s revised findings from 1999 are modified to include only 20 s, as stated in the table.
Gross body movements should include 3 or more discrete body or limb movements within 30 min.
Reprinted with permission from Manning, 1999
Each of the movements evaluated in the BPP results from efferent signals originating in different central nervous system (CNS) centers, which mature at different gestational ages (see Table 2).
Table 2. Maturation of Central Nervous System Regulatory Centers (Open Table in a new window)
Activity
Gestational Age
of Maturation
(wk)
Gross body movements
6
Breathing movements
12-14
FHR accelerations resulting from fetal movement
18-20
Sleep-wake cycles
18-22
Integrated behavioral patterns
28
Table 3 shows a variety of factors, other than hypoxemia, that have been shown to affect different BPP parameters.
Table 3. Factors Affecting the Biophysical Profile (Open Table in a new window)
Activity
FHR
Accelerations
Tone
Gross
Movement
Fetal
Breathing
AFV
Fetal sleep
⇓
⇓
⇓
⇓
Early gestational age (< 33 wk)
⇓
⇓
Late gestational age (>42 wk)
⇓
⇓
⇓
⇓
Maternal glucose ingestion
—
—
⇑
Maternal alcohol ingestion
⇓/—
⇑/—
Maternal magnesium administration
⇓
⇓
Artificial rupture of membranes
⇓
⇓
Premature rupture of membranes
⇓
Labor
⇓
Key: A blank box indicates that no data are available for that parameter.
Horizontal lines indicate that the parameter has been studied and that no change is demonstrated.
Arrows indicate that the parameter has been studied and that it increases or decreases as shown.
The ultrasonographic portion of the biophysical profile (BPP) should begin with notation of the starting time. [2] The profile may be completed when all of the variables have been observed; however, a full 30 minutes must elapse before the profile is judged to be abnormal. The scan should start with a general survey, noting the position of the fetus and the presence of cardiac activity. Although not part of the BPP, surveying the placental position and grade and the fetal morphology is common practice during observation of fetal activity.
Amniotic fluid volume (AFV) is assessed as normal if 1 or more pockets of fluid are detected that measure at least 2 cm along the vertical axis. Oligohydramnios is present if the largest pocket measures less than 2 cm.
The pressure applied to the transducer by the sonographer is inversely proportional to the depth of the fluid pocket. [14] Careful attention to transducer pressure is required to avoid a false diagnosis of oligohydramnios, which can result from excessive transducer pressure compressing the maternal abdomen.
Fetal movements are judged as normal or abnormal according to the criteria established in Table 1. The first video below shows breathing movements, while the second video shows movements that can be mistaken for fetal breathing.
The following videos demonstrate gross movements of the lower and upper body and tone.
The video below demonstrates the amniotic fluid index (AFI) by measuring 4 pockets of fluid.
The AFI is a semiquantitative method for evaluating the AFV. The AFI is derived by adding the largest vertically measured fluid pocket from each uterine quadrant. This method appears to be at least as accurate as the largest–pocket-of-fluid method and can reasonably be substituted as an alternative method for evaluating AFV in the biophysical profile (BPP). Using this method, oligohydramnios is defined as an AFI of less than 5. [15, 16, 17]
To obtain an AFI, the mother must be in the supine position and the linear ultrasonographic probe must be parallel to the maternal spine and perpendicular to the floor for all measurements. The abdomen is divided into 4 quadrants, with the umbilicus delineating the upper and lower halves and the linea nigra delineating the left and right halves.
The largest pocket of fluid in each quadrant is measured along the vertical dimension, which is the dimension perpendicular to the ultrasonographic probe. The pockets must be free of umbilical cord or fetal extremities, although brief appearances of these are acceptable. The video below demonstrates measurement of the AFI.
A modified biophysical profile (BPP), consisting of a nonstress test (NST) and an amniotic fluid index (AFI), is used widely. [18] If either the NST or the AFI is abnormal, a complete BPP or a contraction stress test (CST) is performed. The modified BPP, CST, and complete BPP have similarly low false-negative mortality rates, defined as the number of fetal deaths within 1 week of a normal test result. [19] Nevertheless, no clear evidence exists that the 2 variables used in the modified BPP are better predictors than the other variables omitted from the BPP. [20] Furthermore, this method requires 2 modalities for fetal evaluation, while normal ultrasonographic findings in a BPP eliminate the need for an NST.
Antepartum testing using the biophysical profile (BPP) or any other method should not be performed earlier than the gestational age at which extrauterine survival or active intervention for fetal compromise is possible. Furthermore, no indications exist for testing in a fetus at term when likelihood of successful induction is high or when vaginal delivery is contraindicated for obstetric reasons. For patients with a low probability of successful induction, the BPP is a useful tool that can be used while waiting for cervical ripening. In these patients, the purpose of the BPP is to avoid the maternal morbidity resulting from failed induction followed by cesarean delivery.
The frequency of testing varies according to the clinical variables in each patient. In most high-risk pregnancies, testing plans start with weekly testing, [3] although twice-weekly testing is the standard for pregnancies beyond 42 weeks and for patients with insulin-dependent diabetes. [21] Frequency of testing increases in direct proportion to the severity of the maternal or fetal condition.
In unstable pregnancies with progressive deterioration of the fetal condition, abnormal umbilical cord blood flow patterns occur first. Subsequently, FHR variation is reduced, followed by loss of breathing movements, while general fetal movements and tone are the last parameters to demonstrate abnormal results. Frequent assessment of fetal BPP movements may help prolong the pregnancy in fetuses with a marginally reduced FHR variation.
An abnormal BPS should prompt further evaluation or intervention depending on the circumstances. If an abnormal score occurs in a term fetus, preparation should be made for delivery. An abnormal score in a fetus remote from term requires conservative management, since the risk of fetal death is similar to the neonatal mortality rate resulting from prematurity. In these patients, daily testing often is performed. Table 4 provides general guidelines for treatment following the BPS.
The biophysical profile (BPP) is a reliable method of predicting fetal survival. Data have been collected on this and other antepartum testing procedures for more than 20 years. Testing methods usually are evaluated by comparing the false-negative mortality rate for each method. The false-negative mortality rate is defined as the number of fetal deaths, corrected for lethal congenital anomalies and unpredictable causes of demise, that occur within 1 week of a normal test result.
The BPP has a false-negative mortality rate of 0.77 deaths per 1000 tests. Furthermore, the BPS highly correlates with the antepartum fetal umbilical venous cord pH level.
In a study, cordocentesis performed immediately following a BPP demonstrated that a poor BPS was always associated with a pH of less than 7.20, while a score of 10 of 10 always yielded a pH of greater than 7.20. [22]
The false-negative mortality rate for the nonstress test (NST) alone is 1.9 per 1000 tests, more than twice that of the BPP. The modified BPP has a mortality rate of 0.8. The low false-negative rates of these testing methods depend on an appropriate response to an abnormal result. Intervention and retesting are the usual responses.
ACOG. Antepartum fetal surveillance. In: Practice Bulletin 9. American College of Obstetrics and Gynecology. Oct 1999.
Guimarães Filho HA, Araujo Júnior E, Nardozza LM, Dias da Costa LL, Moron AF, Mattar R. Ultrasound assessment of the fetal biophysical profile: what does an radiologist need to know?. Eur J Radiol. 2008 Apr. 66(1):122-6. [Medline].
Lalor JG, Fawole B, Alfirevic Z, Devane D. Biophysical profile for fetal assessment in high risk pregnancies. Cochrane Database Syst Rev. 2008 Jan 23. CD000038. [Medline].
Alfirevic Z, Neilson JP. Biophysical profile for fetal assessment in high risk pregnancies. Cochrane Database Syst Rev. 2000. CD000038. [Medline].
Booker W, Fox NS, Gupta S, Carroll R, Saltzman DH, Klauser CK, et al. Antenatal Surveillance in Twin Pregnancies Using the Biophysical Profile. J Ultrasound Med. 2015 Nov. 34 (11):2071-5. [Medline].
Payne BA, Kyle PM, Lim K, Lisonkova S, Magee LA, Pullar B, et al. An assessment of predictive value of the biophysical profile in women with preeclampsia using data from the fullPIERS database. Pregnancy Hypertens. 2013 Jul. 3 (3):166-71. [Medline].
Oyelese Y, Vintzileos AM. The uses and limitations of the fetal biophysical profile. Clin Perinatol. 2011 Mar. 38 (1):47-64, v-vi. [Medline].
Turan S, Turan OM, Berg C, Moyano D, Bhide A, Bower S, et al. Computerized fetal heart rate analysis, Doppler ultrasound and biophysical profile score in the prediction of acid-base status of growth-restricted fetuses. Ultrasound Obstet Gynecol. 2007 Oct. 30(5):750-6. [Medline].
Habek D, Salihagic A, Jugovic D, Herman R. Doppler cerebro-umbilical ratio and fetal biophysical profile in the assessment of peripartal cardiotocography in growth-retarded fetuses. Fetal Diagn Ther. 2007. 22(6):452-6. [Medline].
Manning FA, Platt LD, Sipos L. Antepartum fetal evaluation: development of a fetal biophysical profile. Am J Obstet Gynecol. 1980 Mar 15. 136(6):787-95. [Medline].
Manning FA. Fetal biophysical profile. Obstet Gynecol Clin North Am. 1999 Dec. 26(4):557-77, v. [Medline].
Turan S, Miller J, Baschat AA. Integrated testing and management in fetal growth restriction. Semin Perinatol. 2008 Jun. 32(3):194-200. [Medline].
Manning FA, Morrison I, Lange IR, et al. Fetal biophysical profile scoring: selective use of the nonstress test. Am J Obstet Gynecol. 1987 Mar. 156(3):709-12. [Medline].
Flack NJ, Dore C, Southwell D, et al. The influence of operator transducer pressure on ultrasonographic measurements of amniotic fluid volume. Am J Obstet Gynecol. 1994 Jul. 171(1):218-22. [Medline].
Kehl S, Schelkle A, Thomas A, Puhl A, Meqdad K, Tuschy B, et al. Single deepest vertical pocket or amniotic fluid index as evaluation test for preventing adverse pregnancy outcome (SAFE trial): a multicentre, open-label randomised controlled trial. Ultrasound Obstet Gynecol. 2015 Jun 10. [Medline].
Sande JA, Ioannou C, Sarris I, Ohuma EO, Papageorghiou AT. Reproducibility of measuring amniotic fluid index and single deepest vertical pool throughout gestation. Prenat Diagn. 2015 May. 35 (5):434-9. [Medline].
Petrozella LN, Dashe JS, McIntire DD, Leveno KJ. Clinical significance of borderline amniotic fluid index and oligohydramnios in preterm pregnancy. Obstet Gynecol. 2011 Feb. 117 (2 Pt 1):338-42. [Medline].
Eden RD, Seifert LS, Kodack LD, et al. A modified biophysical profile for antenatal fetal surveillance. Obstet Gynecol. 1988 Mar. 71(3 Pt 1):365-9. [Medline].
Nageotte MP, Towers CV, Asrat T, Freeman RK. Perinatal outcome with the modified biophysical profile. Am J Obstet Gynecol. 1994 Jun. 170(6):1672-6. [Medline].
Miller DA, Rabello YA, Paul RH. The modified biophysical profile: antepartum testing in the 1990s. Am J Obstet Gynecol. 1996 Mar. 174(3):812-7. [Medline].
Graves CR. Antepartum fetal surveillance and timing of delivery in the pregnancy complicated by diabetes mellitus. Clin Obstet Gynecol. 2007 Dec. 50(4):1007-13. [Medline].
Vintzileos AM, Gaffney SE, Salinger LM, et al. The relationships among the fetal biophysical profile, umbilical cord pH, and Apgar scores. Am J Obstet Gynecol. 1987 Sep. 157(3):627-31. [Medline].
Biophysical
Variable
Normal
(Score = 2)
Abnormal
(Score = 0)
Fetal breathing movements*
1 or more episodes of ≥20 s within 30 min
Absent or no episode of ≥20 s within 30 min
Gross body movements
2 or more discrete body/ limb movements within 30 min (episodes of active continuous movement considered as a single movement)
< 2 episodes of body/limb movements within 30 min
Fetal tone
1 or more episodes of active extension with return to flexion of fetal limb(s) or trunk (opening and closing of hand considered normal tone)
Slow extension with return to partial flexion, movement of limb in full extension, absent fetal movement, or partially open fetal hand
Reactive FHR
2 or more episodes of acceleration of ≥15 beats per minute (bpm) and of >15 s associated with fetal movement within 20 min
1 or more episodes of acceleration of fetal heart rate or acceleration of < 15 bpm within 20 min
Qualitative AFV
1 or more pockets of fluid measuring ≥2 cm in vertical axis
Either no pockets or largest pocket < 2 cm in vertical axis
*Note: The current clinical management guidelines from the American College of Obstetrics and Gynecology maintain the original findings from Manning et al in 1987. [13] These include the following:
Fetal breathing movements should include 1 or more episodes of rhythmic fetal breathing for at least 30 s or more in 30 min. Manning et al’s revised findings from 1999 are modified to include only 20 s, as stated in the table.
Gross body movements should include 3 or more discrete body or limb movements within 30 min.
Reprinted with permission from Manning, 1999
Activity
Gestational Age
of Maturation
(wk)
Gross body movements
6
Breathing movements
12-14
FHR accelerations resulting from fetal movement
18-20
Sleep-wake cycles
18-22
Integrated behavioral patterns
28
Activity
FHR
Accelerations
Tone
Gross
Movement
Fetal
Breathing
AFV
Fetal sleep
⇓
⇓
⇓
⇓
Early gestational age (< 33 wk)
⇓
⇓
Late gestational age (>42 wk)
⇓
⇓
⇓
⇓
Maternal glucose ingestion
—
—
⇑
Maternal alcohol ingestion
⇓/—
⇑/—
Maternal magnesium administration
⇓
⇓
Artificial rupture of membranes
⇓
⇓
Premature rupture of membranes
⇓
Labor
⇓
Key: A blank box indicates that no data are available for that parameter.
Horizontal lines indicate that the parameter has been studied and that no change is demonstrated.
Arrows indicate that the parameter has been studied and that it increases or decreases as shown.
Peter A Gearhart, MD Assistant Professor of Obstetrics and Gynecology, University of Pennsylvania School of Medicine
Peter A Gearhart, MD is a member of the following medical societies: American College of Obstetricians and Gynecologists
Disclosure: Received honoraria from Merck for speaking and teaching.
Harish M Sehdev, MD Professor of Clinical Obstetrics and Gynecology, Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine; Consulting Staff, Pennsylvania Hospital, University of Pennsylvania Health System
Harish M Sehdev, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Obstetricians and Gynecologists, American Institute of Ultrasound in Medicine, Phi Beta Kappa, Society for Maternal-Fetal Medicine
Disclosure: Nothing to disclose.
William GM Ritchie, MB, BCh Former Clinical Professor of Radiology, University of Pennsylvania School of Medicine; Former Chief, Department of Radiology, Section of Ultrasound, Pennsylvania Hospital
William GM Ritchie, MB, BCh is a member of the following medical societies: American College of Radiology, American Institute of Ultrasound in Medicine, Philadelphia County Medical Society, Radiological Society of North America
Disclosure: Nothing to disclose.
Bernard D Coombs, MB, ChB, PhD Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand
Disclosure: Nothing to disclose.
Karen L Reuter, MD, FACR Professor, Department of Radiology, Lahey Clinic Medical Center
Karen L Reuter, MD, FACR is a member of the following medical societies: American Association for Women Radiologists, American College of Radiology, American Institute of Ultrasound in Medicine, American Roentgen Ray Society, Radiological Society of North America
Disclosure: Nothing to disclose.
Eugene C Lin, MD Attending Radiologist, Teaching Coordinator for Cardiac Imaging, Radiology Residency Program, Virginia Mason Medical Center; Clinical Assistant Professor of Radiology, University of Washington School of Medicine
Eugene C Lin, MD is a member of the following medical societies: American College of Nuclear Medicine, American College of Radiology, Radiological Society of North America, Society of Nuclear Medicine and Molecular Imaging
Disclosure: Nothing to disclose.
Ultrasonography in Biophysical Profile
Research & References of Ultrasonography in Biophysical Profile|A&C Accounting And Tax Services
Source
0 Comments