Remote telemetric monitoring of fetal haemodynamics in pregnant sheep would allow unrestricted animal movement, minimize suffering and distress, and improve animal welfare, while enhancing the quality of data collected. This may also be useful in clinical practice following fetal surgery. Using an open fetal surgical technique at approximately two-thirds of gestation, we implanted the catheter of a D70-PCTP haemodynamic telemetric device (Data Sciences International, Tilburg, The Netherlands) into the carotid artery of the fetal sheep (n = 4). The attached transmitter was secured to the posterior aspect of the maternal anterior abdominal wall. Two receivers, with a range of 1 m each, were sited in an 11 m² sheep enclosure to maximize animal freedom while allowing continuous monitoring of the ewe. The receivers were connected by cable to a nearby computer. In the first two procedures, both fetuses died eight and 12 days after surgery, and the catheter tip was observed to be lying in the bicarotid trunk. In the next two procedures the catheter tip was threaded further upstream from the insertion point, in an attempt to reach the fetal aorta, and both fetuses survived until the scheduled postmortem examination at the end of pregnancy. After catheter implantation, fetal blood pressure (BP) and heart rate (HR) were successfully recorded continuously for seven days and then hourly per day for a further three weeks. The fetal BP and HR values were in the normal range for healthy sheep fetuses.

Fetal cardiac activity was monitored with an external ultrasound transducer in two patients with clinical class III heart disease due to severe mitral stenosis complicated by pulmonary hypertension, undergoing open heart surgery with cardiopulmonary bypass in the 2nd trimester of pregnancy. Fetal distress was detected in one patient, who had mitral valvuloplasty, and was corrected by increasing the rate of blood flow, and the other patient had a mitral valve replacement but no fetal distress was noted. The postoperative course of both mothers and fetuses was uneventful.

The concept of the fetus as a patient has evolved from prenatal diagnosis and serial observation of fetuses with anatomical abnormalities.. Surgical intervention is considered when a fetus presents with a congenital lesion that can compromise or disturb vital function or cause severe postnatal morbidity. Hydronephrosis, saccrococcygeal teratoma, hydrocephalus, meningomyelocoele and diaphragmatic hernia are some of the defects that can be diagnosed by imaging and are amenable to intervention. The combination of underdeveloped organ function and usually life-threatening congenital malformation places the fetus at a considerable risk. Fetal surgery also leads to enhanced surgical and anaesthetic risk in the mother including haemorrhage, infection, airway difficulties and amniotic fluid embolism. There are 3 basic types of surgical interventions: 1.Ex utero intrapartum treatment(EXIT), 2.Midgestation open procedures, 3.Minimally invasive midgestation procedures. These procedures require many manipulations and monitoring in both the mother and the unborn fetus

We developed an algorithm for high-quality, non-invasive maternal and fetal ECG (fECG) monitoring. We tested its ability to extract fECG from a single channel maternal thoracic ECG signal rather than the routine abdominal signal, and compare it with other algorithms. At 126dG, ECG was attached to near-term ewe and fetal shoulders, manubrium and xyphoid processes (n=12). Fetal ECG served as the ground-truth to which the fetal ECG signal extracted from the simultaneously-acquired maternal ECG was compared. The fECG extraction algorithm requires three steps. First, the de-shape short-time Fourier transform (STFT) is applied to estimate the maternal instantaneous heart rate, and hence maternal R peaks. Second, the nonlocal Euclidean median (NLEM) is applied to recover the maternal ECG. By direct subtraction, we obtain the rough fECG. Third, the fetal R peaks and fECG are obtained by applying the deshape STFT and the NLEM. All fetuses were in good health during surgery. In all animals, our algorithm and two widely applied single lead fetal ECG extraction algorithms failed to extract any fECG from the thorax maternal ECG signal with the F1 less than 50%. The applied fECG extraction algorithms might be unsuitable for the thoracic maternal ECG signal, or the latter does not contain strong enough fECG signal, although the lead is near the mother's abdomen. Fetal sheep model is widely used to mimic various fetal conditions, yet ECG recordings in a public data set form are not available to test the predictive ability of fECG and FHR. A challenge is the requirement to perform a sterile fetal surgical instrumentation with precordial ECG leads. We are making this data set openly available to other researchers and inviting others to share their maternal/fetal ECGs to foster non-invasive fECG acquisition in this animal model.

It has been shown that MRI offers the possibility of more detailed assessment of fetal pathology than sonography. It is used not only to diagnose but also to follow up some prenatal diseases. It is a basis of in utero treatment and the tool of monitoring its efficacy The purpose of the study was to present the authors' experience with prenatal MRI as a method of follow-up of fetal pathology and of monitoring invasive fetal therapy The study group consisted of 31 fetuses that underwent two MRI examinations. The first exams were performed at the gestational age of 19-28 weeks (mean: 23.6 weeks), the follow-up between week 20 and 37 (mean: 30.5). The MRI examinations were performed using 1.5 T scanners. SSFSE/T2-weighted images, TSE/ or GRE/T1-weighted images, DWI, FIESTA, EPIGRE were performed. In 5 cases MRI allowed to exclude a suspected pathology: brain anomaly in a healthy fetus, septo-optic dysplasia in a healthy fetus, right-sided CDH in case of a left-sided pathology pentalogy of Cantrell, lack of bladder in a fetus with a small, thick-walled bladder In 4 cases an additional pathology was detected on MRI: CCAM/ pulmonary sequestration with self-regression, cerebellar hypoplasia, rhombencephalosynapsis, tethered cord with syringohydromyelia. In 4 cases MRI was used just to follow-up and showed evolution of the disease in 2 cases: regression of intracerebral hemorrhage, progression of kidney disease. Finally, in 18 cases MRI was performed before and after an open fetal surgery of myelomeningocele showing good outcome in 10 cases and a wide spectrum of complications in 8 neonates: from edema of the transplant only in 4 to recurrent MC in 1. Maternal uterus constitutes a natural "incubator" for the fetus--it is easier and safer to perform diagnostic procedure in utero than in a seriously ill newborn. MRI is a method of choice in the diagnosis and of follow-up in cases of open fetal surgery.

SummaryThere are few congenital anomalies that can be treated in utero, despite the rapid development of fetal medicine. The number of available antenatal treatments is growing with the advance of supplementary tools, especially ultrasound and endoscopy. Disorders involving accumulation of excessive fluid in the amniotic cavity (polyhydramnios), chest (hydrothorax), abdomen (ascites) and urinary system (obstructive uropathy) are regularly treated using aspiration or shunt drainage under ultrasound monitoring. Electrolyte solutions or concentrated blood component supplements are used to treat oligohydramnios (amnioinfusion and amniopatch) and fetal anemia (fetal transfusion). Placental tumor (chorioangioma) and fetal tumors (cystic hygroma and sacrococcygeal teratoma) are also successfully treated by antenatal injection of medications. Fetoscopic procedures, especially obstetric endoscopy, are now used regularly in North America, Europe, Australasia and Japan after the validity was established in the treatment of twin-twin transfusion syndrome when compared with traditional amnioreduction. However, most procedures involving surgical fetoscopy or open fetal surgery remain experimental. Their validity and efficacy are not confirmed in a number of fetal diseases for which they were claimed to be effective. A brief review of the global status and history of invasive fetal therapy is given, and its status in Taiwan is also described. Future development in this field relies on greater understanding of the basic physiology and pathology of the diseases involved, as well as on the progress of sophisticated instrumentation