Katsuya Hisano

A New Artificial Placenta with a Centrifugal Pump: Long-Term Total Extrauterine Support of Goat Fetuses

PURPOSE We tried long-term total extrauterine support of goat fetuses at high pump flow, which was pulsatile and synchronized with the cardiac cycle and at low oxygen tension in the umbilical artery and vein by use of the new artificial placenta. METHOD This system consisted of an arteriovenous extracorporeal membrane oxygenation using umbilical artery and vein and a thermoregulated water bath. Five goat fetuses (125 +/- 0.7 days of gestation, 2.0 +/- 0.9 kg) were incubated in lactated Ringers solution. Mean pump flow rate ranged from 113 +/- 16 to 193 +/- 13 ml/min/kg, and umbilical arterial oxygen tension was maintained at 20 +/- 3 to 23 +/- 5 mm Hg for five fetuses. RESULT Blood gas analysis echocardiogram showed that fetal circulation and sufficient oxygen consumption could be maintained, and fetal extrauterine support conditions were made as similar as possible to physiologic circulatory conditions. We achieved long-term extrauterine support of goat fetuses up to 237 hours (mean 137 +/- 58 hours). CONCLUSION We believe that this system can be used for experimental models of the fetus and will come into clinical application for fetal extrauterine support systems and backup systems for fetal operations.

Eventration of the Diaphragm in Infants and Children

ABSTRACT. The study reviews 18 infants and children with eventration of the diaphragm who were treated over a period of eight years. The affected diaphragm and pulmonary tissue were examined by light and electron microscopy. The 18 patients, ranging in age from 10 days to 6 years, were divided according to Thomas’classification into a group with the congenital (10 patients) and a group with the acquired type (8 patients). Fifteen of these patients underwent surgery with diaphragmatic plication. On microscopic examination, biopsies of the lung showed atelectasis and pneumonia. These pathological changes became increasingly diffuse and severe with age. The diaphragm in patients with the congenital type of eventration was occupied by diffuse fibroelastic tissue. In patients with the acquired type, the cross‐striated muscles of the diaphragm showed degenerative changes such as fragmentation, and interstitial fibrosis of the diaphragm became prominent with age. The results of this clinical study sugget that, in order to reduce the pathological changes in the lung, early surgical plication should be performed even in patients with the acquired type, if respiratory and digestive symptoms are noted.

Combined Resection of the Thoracic Esophagus and Thoracic Descending Aorta

We conducted combined resection of the thoracic esophagus and thoracic descending aorta in 2 patients, one with advanced esophageal cancer with aortic invasion and the other aortoesophageal fistula caused by a false aortic aneurysm. Combined resection of esophageal tumor and adjacent involved organs was conducted in 14 patients with A3:T4 esophageal cancer but none survived 3 years and resecting tumor-invaded organs did not improve patient survival. One major problem of combined resection of the esophagus and aorta is contamination of the posterior mediastinum. In 1 patient, 2-stage surgery for the esophagus and in situ aortic replacement was conducted to reduce operative risk and avoiding infection of the prosthetic vascular graft. With thoracic descending aortic aneurysm adjacent to the esophagus on the increase, cardiovascular surgeons should prepared to undertake combined resection of both the aorta and esophagus.

Ligation of medically refracted patent ductus arteriosus (PDA) in an extremely low body weight premature infant

Medically refracted patent ductus arteriosus (PDA) in an extremely low birth weight (ELBW) preterm (gestation 24 weeks 2 days) infant was successfully ligated under general anesthesia in the neonatal intensive care unit (NICU). Pharmacological agents are more effective to close PDA in preterm infants than in full-term infants, although within 48 h three doses of indomethacin were not sufficient to close PDA in this case. At the age of 69 h the infant developed severe symptoms including bradycardia, systemic hypotension, pulmonary hypertension, diastolic steal (reverse distal aorta flow velocity), and anuria. A PDA ligation was thus performed surgically at 72 h of age. General anesthesia and surgical stress were tolerated by this 531 g infant. Postoperatively all symptoms improved dramatically and the general conditions were stable. On the 38th day the endotracheal tube was extubated and on the 50th day nasogastric milk feeding was started. The oxygen supply was weaned on the 78th day. Growth and development until 6 months were within the normal range of very low birth weight infants. A surgical ligation as early as possible in medically refracted PDA in an ELBW infant is thus considered to be a safe and effective treatment. It prevents the development of further complications of cardiopulmonary vascular problems. Color Doppler echocardiography can reliably measure the PDA size, flow velocity, and hemodynamic changes of persistent PDA, even in tiny infants.

Management of cholelithiasis in combination with cardiovascular surgery

A retrospective review of the perioperative management of patients with cardiovascular surgical disorders and cholelithiasis was conducted, and the surgical strategies employed are discussed. Between 1988 and 1998, 18 patients having cardiovascular surgical disorders underwent cholecystectomy. These patients were divided into three groups: group I, given a one-stage operation (n = 9); group II, given a two-stage operation (n = 3); and group III, given cholecystectomy during follow-up after cardiovascular surgery (n = 6). In group I, a median laparotomy was adopted for patients with an abdominal aortic aneurysm (AAA) to allow both disorders to be treated through the same incision, whereas a right subcostal approach was employed to separate the incisions for patients who underwent cardiac operations. In group II, one patient underwent cholecystectomy before cardiac surgery, and two patients underwent cholecystectomy for postoperative cholecystitis after cardiovascular operations. One patient from group II and all from group III were on preoperative anticoagulant therapy, two of whom underwent laparoscopic cholecystectomy. No fatal complications such as prosthetic infection, intraperitoneal hemorrhage, or cerebral attack were encountered. In conclusion, we consider that performing cholecystectomy during AAA repair may be safe and prevents the risk of postoperative cholecystitis; it is preferable to treat cholelithiasis coexisting with cardiac disorders concomitantly with or before cardiac operations; and laparoscopic cholecystectomy can be safely performed under anticoagulant therapy.

Multiple calcified aneurysms of splenic artery, hypersplenism and concomitant cholelithiasis

Multiple calcified, aneurysms of splenic artery with hypersplenism and concomitant cholelithiasis were found in a 73-year-old Japanese woman. The symptoms and radiological findings were referable to the aneurysms. The predisposing factors are reviewed. Proximal ligation of the splenic artery and splenectomy gave a good postoperative result. Histopathological examination revealed an atherosclerotic origin, nevertheless specimens from an elderly person may obscure the actual pathology.

LAPAROSCOPIC ORCHIOPEXY OF INTRAABDOMINAL UNDESCENDED TESTIS ASSOCIATED WITH CONGENITAL DIAPHRAGMATIC HERNIA

Laparoscopy is an advantageous method for the repair of intraabdominal undescended testis since both an abdominal exploration and vascular elongation can be effectively performed by laparoscopic assistance. A 3-year-old boy and a 1-year-old boy complaining of unilateral nonpalpable left testes were observed following previous congenital diaphragmatic hernia repairs on the day of birth. In these operations, a laparoscopic working sheath was inserted through a small supraumbilical incision. On each boy, a laparoscopically intraabdominal testis was found close to the left internal inguinal ring. In addition, a 10-mm trocar port was placed in the right lower abdominal quadrant and a 5-mm port was placed in the left lower quadrant. For the purpose of orchiopexy, the left testicular vessels were isolated over their full length. The left side of the testis was pulled through the inguinal ring to an inguinal canal divided by the abdominal wall, and then was retracted into the scrotum. The internal ring was thereafter closed externally by the fascia transversalis. Both patients are doing well, with no testicular atrophy or inguinal hernia for 1 and 2 years, respectively, after the above operations.