Conjoined twins: Pre-birth management, changes to NRP, and transport

Advanced imaging and modeling in neonatal simulation

Advances in modeling and imaging have resulted in realistic tools that can be applied to education and training, and even direct patient care. These include point-of-care ultrasound (POCUS), 3-dimensional and digital anatomic modeling, and extended reality. These technologies have been used for the preparation of complex patient care through simulation-based clinical rehearsals, direct patient care such as the creation of patient devices and implants, and for simulation-based education and training for health professionals, patients and families. In this section, we discuss these emerging technologies and describe how they can be utilized to improve patient care.

Integrated multiomics reveal the molecular characteristics of conjoined twin fetuses

RESEARCH QUESTION

Are there any differences between conjoined twin fetuses at the molecular level?

DESIGN

Skin tissues were collected from thoracopagus conjoined twins at 15+4 weeks of gestation. The skin tissues were collected from the thigh side of conjoined twins after the abortion procedure. All specimens were obtained after written informed patient consent and were fully anonymized. All relevant ethical regulations were followed. Every specimen underwent multiomics sequencing analysis to determine associations among the DNA methylome, transcriptome and mutations in the exon regions in the conjoined twins.

RESULTS

The global methylation pattern was similar in the two fetuses of conjoined twins, while significant differences were seen in local regions such as CpG islands (P = 0.026), enhancers (P < 0.001) and various repetitive elements (P < 0.05), which showed significant differences. The conjoined twins also differed in genes related to growth and development, cellular component morphogenesis and cellular stress, both in terms of DNA methylation levels and gene expression levels. Exon data analysis revealed that the common mutations in conjoined twins mainly occurred in neural development, lipid metabolism and microtubule morphogenesis. Specific mutations were associated with cellular component biosynthesis, behaviour and germ cell development.

CONCLUSION

Conjoined twins were similar to each other globally, but there were significant differences related to growth and development, cellular component morphogenesis and cellular stress. The current study reveals the molecular features of conjoined twins for the first time, laying the foundation for future exploration of the mechanism of conjoined twins.

Conjoined twins in dichorionic diamniotic triplet pregnancy: a report of three cases and literature review

Background

Conjoined twins are a rare and serious complication of monochorionic twins. The total incidence is 1.5 per 100,000 births, and about 50% are liveborn. Prenatal screening and diagnosis of conjoined twins is usually performed by ultrasonography. Magnetic resonance imaging can be used to assist in the diagnosis if necessary. Conjoined twins in dichorionic diamniotic triplet pregnancy are extremely rare.

Case presentation

We reported three cases of dichorionic diamniotic triplet pregnancy with conjoined twins. Due to the poor prognosis of conjoined twins evaluated by multidisciplinary teams, selective termination of conjoined twins was performed in three cases. In case 1, selective reduction of the conjoined twins was performed at 16 gestational weeks, and a healthy female baby weighing 3270 g was delivered at 37 weeks. In case 2, the conjoined twins were selectively terminated at 17 weeks of gestation, and a healthy female baby weighing 2760 g was delivered at 37 weeks and 4 days. In case 3, the conjoined twins were selectively terminated at 15 weeks and 2 days, and a healthy female baby weighing 2450 g was delivered at 33 weeks and 6 days. The babies of all three cases were followed up and are in good health.

Conclusion(s)

Surgical separation is the only treatment for conjoined twins after birth. Early determination of chorionicity and antenatal diagnosis of conjoined twins in triplet gestations are critical for individualized management options and the prognosis of normal triplets. Expecting parents should be extensively counseled by multidisciplinary teams. If there are limitations in successful separation after birth, early selective termination of the conjoined twins by intrathoracic injection of potassium chloride may be a procedure in dichorionic diamniotic triplet pregnancy to improve perinatal outcomes of the normal triplet.

Conjoined twins: an obstetrician's guide to prenatal care and delivery management

OBJECTIVE

Obstetricians infrequently encounter conjoined twins. Much of the clinical care literature focuses on postnatal management from a neonatology and pediatric surgery perspective; guidance on obstetrical management is limited. We outline steps for prenatal evaluation, obstetrical care, and delivery planning.

STUDY DESIGN

Experiences with two cases of conjoined twins.

RESULTS

We identified several points throughout the planning, delivery, and postnatal process that are important to highlight for optimizing clinical outcome, patient safety, and parental satisfaction.

CONCLUSION

After diagnosis, patients should be referred to a center experienced in the management of conjoined twins. Specialists in fields including maternal fetal medicine, pediatric surgery, neonatology, and radiology play a vital role in the management of these patients. Early referral allows for timely family counseling and decision-making. Prenatal evaluation beyond the first trimester should include a detailed ultrasound, fetal echocardiogram, and fetal MRI. 3D printed life-sized models can improve delivery planning and patient understanding.

The Outcomes of Surgical Separation in Thoracopagus Twins with Conjoined Hearts: An Analysis of the Literature

We sought to perform a comprehensive review of reported cases of conjoined thoracopagus twins with cardiovascular conjunction to determine the overall survival after separation and factors that might be associated with survival. We performed a systematic review of cases of thoracopagus twins with conjoined cardiovascular systems reported in the English medical literature using Embase, PubMed, Web of Science, and Scopus. We employed standard statistical methods to analyze differences among groups. We identified 102 unique cases of thoracopagus twins (69% female) with some degree of cardiovascular conjunction who had undergone surgical separation. We identified 6 distinct types of cardiovascular union. Median age was 47 days (IQR 12, 120). Survival to at least hospital discharge occurred in 51% (105/204). Median age at separation was lower in emergent (9 days, IQR 1, 25) versus elective cases (93 days, IQR 49, 180) (p < 0.0001). Survival to hospital discharge was higher in those who underwent elective separation (70%, 93/132 total children versus 17%, 12/72) (p < 0.0001). Survival was associated with the type of cardiovascular union (p < 0.0001). The separation of thoracopagus twins with cardiovascular conjunction is higher than expected. Increased survival is associated with elective separation, older age, and shared pericardium only. These findings suggest survival could be improved with better delineation of degree of union and delayed separation.

Airway management protocol for conjoined twins delivery

OBJECTIVE

Conjoined twin deliveries require collaborative preparation by multiple specialties for successful airway management. Literature regarding neonatal airway management after conjoined twin delivery is limited to case reports. We present a case series of conjoined twins and introduce an airway management protocol for conjoined twin delivery.

METHODS

The medical records of conjoined twins and their mothers at a tertiary care center were reviewed from April 2016 to December 2018. The NCBI database was queried for literature regarding preparation for neonatal airway management after conjoined twins delivery.

RESULTS

Five sets of conjoined twins were delivered. Of 10 neonates, all required bag valve mask ventilation. Other airway interventions included continuous positive airway pressure (7), endotracheal intubation (6), and direct laryngoscopy with telescopic video evaluation (1). No patients required ex-utero intrapartum treatment or emergent tracheostomy. A protocol for airway management is described and special considerations are discussed, including anatomic variations, equipment list, operating room staffing and layout, multidisciplinary prenatal conference, and airway imaging review.

CONCLUSION

Conjoined twin deliveries have significant implications for the otolaryngologist and require multidisciplinary collaboration. An airway management protocol allows for a standardized process to secure the neonatal airway and optimize patient outcomes.

Conjoined twins in 2020 - state of the art and future directions

PURPOSE OF REVIEW

A number of high profile conjoined twin separations have been extensively covered by the world media. Anaesthesia for conjoined twins is a procedure rarely experienced by paediatric anaesthetists. The increased survival of the twins has prompted discussion as to the most appropriate selection of patients, teams and hospitals to provide exceptional anaesthetic care.

RECENT FINDINGS

The number of conjoined twins presenting for surgery remains low with many infants not surviving foetal or early neonatal life. Anaesthetic management of less common conjoined infants such as craniopagus twins has highlighted the benefit of careful patient selection, extensive preoperative investigations and meticulous multidisciplinary team planning. The role of simulation of possible adverse perioperative events has been highlighted. Three dimensional anatomical models and virtual reality systems have permitted surgical planning in advance of actual intervention. A number of legal and ethical concerns have been reported especially in the setting of emergency separation where surgery is likely to contribute to death of one of the twins.

SUMMARY

There appears to be an expanding role for international teams with extensive separation experience becoming involved in international teleconferencing to improve patient management in low-resource countries. Whether the perioperative outcome is better when the conjoined twins are transferred to major centres for surgery or teams operate in the twin's country of origin remains to be seen.