Combined interstitial laser cauterisation of placental anastomosis and intrauterine intracardiac transfusion following monochorionic co-twin demise: a case report

Abstract

Single fetal demise in monochorionic pregnancy is associated with significant morbidity and mortality of the co-twin. We report the case of a 36-year-old nulliparous woman with unexpected single fetal demise in a monochorionic twin pregnancy diagnosed at 15 weeks and 4 days. She had been well since her last normal scan at 13 weeks and 3 days and no discordance in crown rump length or nuchal translucency thickness had been evident. Noninvasive prenatal testing for common aneuploidy screening was negative.Ultrasound showed demise of one twin and scalp oedema and ascites in the surviving co-twin. Cardiothoracic ratio was elevated to 0.59 and tricuspid regurgitation was seen. Peak systolic velocity (PSV) of the middle cerebral artery (MCA) was increased to 2.18 multiples of median (MoM; 45.1 cm/s) and diastolic flow in the umbilical artery was absent. Cord insertion was velamentous and an arterial anastomosis was identified along the placental surface from the surviving twin to the placental cord insertion of the miscarried twin (Fig 1a and b).The couple were counselled extensively on management options that included termination of pregnancy, conservative management, or active intrauterine interventions. Within 24 hours, the patient opted to undergo rescue transfusion for fetal anaemia and interstitial laser cauterisation of the placental anastomosis. Interstitial laser cauterisation was performed using an 18G spinal needle inserted transplacentally under ultrasound guidance to the anastomotic artery close to the cord insertion of the miscarried twin. A 780-µm laser fibre was advanced to 3 mm beyond the needle tip. Cauterisation was started with a 20-W diode laser and stepped up to 40 W for 100 s. Fetal heart pulsation was checked intermittently and was normal throughout. Cessation of blood flow was confirmed by colour Doppler ultrasonography (Fig 1c).Intracardiac transfusion was performed