Monday, February 15, 2016

Cerebral Palsy: Can the obstetric profession be absolved of the long felt guilt?

Cerebral Palsy is a devastating disease diagnosed in 1 per 326 children according to the Center for Disease Control & Prevention. Population-based studies from around the world report prevalence estimates of CP ranging from 1.5 to more than 4 per 1,000 live births or children of a defined age range.

There are 17 million people worldwide whose lives have been affected by cerebral palsy.

Cerebral palsy (CP) is the most common motor disability in childhood and at present there is no cure for the disease.

Recent advances in regenerative and transplantation medicine have experimented with transplantation of stem cells in animals models , particularly umbilical cord blood cells with mixed results. Two major clinical trials, placebos controlled, crossover and observer blind are underway in US at Georgia Regents University and Duke University using umbilical cord blood stem cells for transplantation.  These studies are currently recruiting participants.

Currently all studies are preliminary and It will take a number of years for safe and effective therapies to make it to the clinic for general public. Although some Unregulated European and Asian clinics are offering the treatment but the possibilities for misinformation and exploitation cannot be denied.  

The birth of a baby with CP is often viewed as failing of the obstetric and maternity services to manage labour causing an intrapartum hypoxic insult. Over recent years it has been perceived that the cerebral palsy has a multifactorial origin, and includes genetic, infective, nutritional, and immune, as well as obstetric factors.

The obstetric causes are placental abruption, prolonged PROM, chorioamnionitis, IUGR, pre-eclampsia, multiple births and placenta praevia; however, only 10% of cases of CP in the developed world are caused by cerebral hypoxia during birth. With this disclosure can the obstetric profession breathe a collective sigh of relief?

A large population based cohort study by Strand et al published in the forthcoming issue of  BJOG:An International Journal of Obstetrics & Gynaecology has suggested that placental dysfunction could be a major factor  involved in causal pathways leading to the more severe subtypes of CP.

Among a total of 533743 singleton liveborn children in Norway during 1999–2008, 779 children were diagnosed with CP. Low placental weight was found to be a risk factor for CP, as were low placental weight/birthweight ratio and low placental weight/birth length ratio. The birth length ratio was more important in causation, suggesting the occurrence of hypoxic insult early in pregnancy.

In recent years, the placenta has not received much importance when evaluating fetal wellbeing. A recent study in the journal Placenta has associated abnormal placental morphometry with first-trimester pregnancy-associated plasma protein–A (PAPP–A) levels in patients with preeclampsia and IUGR, which themselves are associated with CP.

With the advancement in Ultrasound techniques, Doppler measurement of the umbilical arteries and fetal microcirculatory changes over the last three decades; it is possible to identify babies with decreased placental function.  The difficulty lies in identifying the babies that require such intervention, a task that we still undertake poorly maybe because of limited treatment capacity at present.

Placental volume can be measured accurately by MRI and can be compared to fetal volume antenatally in suspected cases. Even basic measurement of placenta like, weight and dimensions at delivery can be helpful in this regard.

Even abnormal placental weight in patients with preeclampsia predicts adverse neonatal outcome.  Placental investigation can contribute to neonatal risk assessment.

Infact, so little is known about placenta as a human organ that in USA, the National Institutes of Health (NIH) have launched a Human placenta project. One of the main goals of the project is to develop new technologies for the real-time assessment of placental development, allowing for the study of placental function in normal versus abnormal pregnancies.

So, although obstetrician may have been excused of suboptimal intrapartum management leading to CP, the obstetrician still has to look into causation of abnormal placentation early in pregnancy  possibly leading to CP.



References:

http://www.obgynnews.com/specialty-focus/obstetrics/single-article-page/what-does-the-human-placenta-project-mean-for-obstetrics-care/39692d362b41581b2734e4ecffacc2dd.html


No comments:

Post a Comment