title: Congenital cystic adenomatoid malformation in the newborn: two case studies and review of the literature.
abstract: Congenital cystic adenomatoid malformation (CCAM) is a congenital malformation of the lung that can present on imaging studies as abnormal air, air/fluid-filled cysts, or fluid-filled/solid-appearing cysts. The use of ultrasound in prenatal management has increased the number of cases diagnosed in utero. Early diagnosis is vital in the medical management of CCAM. Outcome varies from hydrops and fetal demise to complete resolution before birth. Many CCAMs diagnosed in utero may decrease in size even if substantial mediastinal shift and lung compression are noted at the time of diagnosis. Once the disorder has been diagnosed, use of serial ultrasound is helpful in providing medical management of the fetus. Two cases of CCAM in the newborn are presented that reflect characteristic clinical features but with distinctly different outcomes, one patient successfully responding to resection and ventilatory support, the other succumbing in the first day of life. The embryology, histology, prenatal and postnatal clinical presentation, and treatment of this malformation are discussed on the basis of a review of the literature. Recent developments in fetal diagnosis and treatment, including fetal surgery, are also presented. We conclude that CCAM should be considered in the differential diagnosis in the presence of respiratory distress and mediastinal shift. It is especially important for respiratory therapists, nurses, and other members of neonatal transport teams to consider CCAM in the differential diagnosis for any patient who presents with respiratory distress and a chest radiograph showing mediastinal shift. The treatment of choice for this lesion is surgical resection by either segmentectomy or lobectomy. Even in cases of relatively asymptomatic patients with CCAM, surgical resection should be considered because of the reported association of carcinoma and unresected CCAM. (IO2)) of 1.0 at a rate of 60-100 breaths per minute, there was slight improvement in oxygen saturation, to 50-70%. The postintubation radiograph showed bilateral haziness, with a mediastinal shift to the right. An umbilical venous catheter was placed and a venous blood gas study revealed a pH of 6.82, partial pressure of carbon dioxide of 100 mm Hg, and partial pressure of oxygen of 36 mm Hg. A needle aspiration of the left chest wall was performed to relieve the mediastinal shift; it produced approximately 40 mL of clear fluid. A repeat chest radiograph showed a possible pneumothorax on the left and continued mediastinal shift. A left-side chest tube was inserted and clear fluid continued to drain, but an additional chest radiograph was unchanged. Needle aspiration was then performed on the left side, and a large amount of air was removed. The S(pO2) increased to 88%, and the heart rate and blood pressure remained stable. The patient was then prepared for transport and placed on a Biomed MPV 10 (Bio-Med Devices, Guilford, Connecticut), intermittent mandatory ventilation rate 120, peak pressure 25 cm H(2)O, positive end-expiratory pressure 5 cm H(2)O (25/5), and F(IO2) 1.0. A venous blood gas study just before transport showed a pH of 7.1 and a P(CO2) of 45 mm Hg. The S(pO2) at that time was between 60% and 70%. To facilitate ventilation during transport, the patient was also given pancuronium (Pavulon) and morphine. On arrival at the neonatal intensive care unit, the patient was placed on a Sensormedics High-Frequency Oscillator (Sensormedics Corporation, Yorba Linda, California) with an initial amplitude of 70, airway pressure 25 cm H(2)O, inspiratory time 33%, Hertz 13, and F(IO2) 1.0. Three additional chest tubes were placed in the left hemithorax, which initially evacuated air, followed by serosanguineous fluid. The S(pO2) briefly increased to above 90%. A repeat chest radiograph again showed persistence of the left-sided collection of air and mediastinal shift. (ABSTRACT TRUNCATED)
authors.affiliation: Section of Neonatology, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA.
authors.forename: S E
authors.initials: SE
authors.lastname: Sittig
authors.forename: G F
authors.initials: GF
authors.lastname: Asay
mesh_terms: D001344:Autopsy; D015615:Cystic Adenomatoid Malformation of Lung, Congenital / Q000175:diagnosis* / Q000628:therapy*; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007442:Intubation, Intratracheal; D010092:Oximetry; D012121:Respiration, Artificial; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome