Norihiro Niimi

Development in lung function of the affected side after repair of congenital diaphragmatic hernia

The widespread use of newly developed techniques including extracorporeal membrane oxygenation (ECMO) has led to the survival of a number of patients with congenital diaphragmatic hernia (CDH) and associated hypoplastic lung. However, it is not fully recognized whether the hypoplastic and small lung of the affected side has the ability to develop its function after repair of CDH. The authors studied the lung function of 32 patients with CDH in whom these new methods were used. Two parameters, lung volume and pulmonary perfusion amount, were used to evaluate lung function. The former (checked by computed tomography scan) was used to evaluate the size of lung; the latter (checked by perfusion scintigram) was used to assess vascular density. The patients were divided into two groups, based on values of alveolar-arterial difference in oxygen content (AaDo2) at the time of admission. In group A (AaDo2 < 500 mm Hg; 12 cases), whose respiratory distress was mild and could be managed with ventilator care alone, the mean lung volume value for the affected side was 86% of the contralateral lung value from the initial study, and reached 93% at the time of follow-up study. The perfusion amount also exceeded 80% of the contralateral lung value from the initial study. Thus, it is likely that group As affected-side lung is not small and has developed at a rate similar to that of the contralateral lung. However, in group B patients (AaDo2 > 500 mm Hg; 20 cases), who had severe respiratory distress at the admission and were managed with new techniques including ECMO, both lung volume and perfusion amount of the affected side initially were low in all cases (ie, mean values were 61% and 53% of contralateral-lung values, respectively). At the time of follow-up, the lung volume had increased in most cases (mean value, 88% of the contralateral lung value), but the perfusion amount of the affected side had not increased in most cases. It remained low, or decreased to below the initial value; the mean was 53% of the contralateral lung value. The initial mean perfusion: volume ratio (87%) had decreased significantly (to 62%) by the time of follow-up. This tendency was exaggerated in the 11 ECMO cases. These data might indicate that in most group B cases, the lung of the affected side has little ability to develop arterial branches, or certainly will be delayed in comparison to the contralateral lung, and that enlargement of lung volume may depend on overexpansion or emphysematous change rather than cellular growth. The present data also suggest that, in group B cases, total lung function will depend on the contralateral lung for a relatively long time.

Application of a new anticoagulant (nafamostat mesilate) to control hemorrhagic complications during extracorporeal membrane oxygenation—A preliminary report

Bleeding related to systemic heparinization has been considered one of the major complications associated with extracorporeal membrane oxygenation (ECMO). Development of the heparin-bonded system will be essential in reducing hemorrhagic complications, but has not yet been clinically proven. The authors chose an alternative approach of making a difference in the activated clotting time (ACT) values between the patient and the ECMO circuit, and decreased only the patients ACT value, while keeping the value of the ECMO circuit at an ideal level. For this purpose, we have used a very short-life anticoagulant, Nafamostat Mesilate (FUT), while decreasing the dose of heparin. FUT is a synthetic protease inhibitor that has been found to inhibit various kinds of enzyme activities for coagulation. Twelve newborns who had some hemorrhagic complications at various sites before or during ECMO, were selected to receive FUT. The heparin dose was decreased after FUT administration into the drainage route. FUT and heparin doses were regulated to maintain the ACT value at the reinfusion route at 190 to 220 seconds. ACT values at the drainage and the reinfusion routes were simultaneously measured. The average time on FUT was 100.3 +/- 86.3 (SD) hours. The average dose of FUT was 0.48 +/- 0.22 mg/kg/h, and that of heparin was 21.0 +/- 7.5 U/kg/h. The average ACT value at the reinfusion route was 205.7 +/- 14.0 seconds compared with that at the drainage route of 178.5 +/- 11.8. The difference was statistically significant (P < .001). The average difference in ACT values between both routes was 27.1 +/- 7.9 seconds. The bleeding was well controlled by FUT administration in 8 of 12 cases. This report may represent the first clinical use of FUT in neonatal ECMO, and serve as a preliminary study.

Isolated cavernous hemangioma of the stomach in a neonate

This is a report of an extremely rare case of isolated cavernous hemangioma of the stomach found in a neonate. Hematemesis developed in a 7-day-old baby boy weighing 2.8 kg at birth. This was followed by melena. Endoscopic examination findings showed a large hemorrhagic mass on the lesser curvature of the stomach. During laparotomy, a large vascular tumor was identified and subtotal gastrectomy was carried out. On section, the tumor extended through the submucosa to the serosal surface. Histological diagnosis was cavernous hemangioma. The authors could collect only 10 cases of hemangioma of the stomach diagnosed in childhood from the world literature.

Analysis of patients with congenital diaphragmatic hernia requiring pre-operative extracorporeal membrane oxygenation (ECMO)

Abstract The purpose of this report was to analyze the patients requiring preoperative extracorporeal membrane oxygenation (ECMO) as the most critical group of patients with congenital diaphragmatic hernia (CDH) and to identify any special features. Over the past 11 years, out of 72 neonates with CDH admitted before 24 h of age, 40 (56%) could be managed with conventional therapies while the other 32 (44%) required ECMO. Seventeen infants requiring preoperative ECMO were classified as group 1, and the 15 with postoperative ECMO as group 2 (controls). The records of patients in both groups were analyzed. Patients in group 1 were not only severely hypoxic, but also significantly hypercapneic on admission, and in 14 (82%) the diaphragmatic defect was so large or totally agenetic that a prosthetic patch was necessary. The average age at onset of ECMO in group 1 was 13.1 h, and the average duration was 159 h. Major hemorrhagic complications including intracranial hemorrhage occurred with a significantly higher frequency in group 1. The survival rate in group 1 was 41%, compared with 73% in group 2 and 85% in non-ECMO patients. Four infants in group 1 with extremely hypoplastic lungs could not be weaned from ECMO, and died without undergoing an operation. Moreover, 4 of the 7 survivors in group 1 required prolonged (105–658 days) ventilator care with a tracheostomy after weaning from ECMO, and were frequently hospitalized thereafter. The pulmonary function of these patients remained severely underdeveloped for a long time; indeed, the average pulmonary perfusion ratio of the affected side remained at only 40% of the contralateral side in group 1, although the volume ratio reached 85%. These findings may suggest that the main pathology of the patients requiring preoperative ECMO was a high degree of pulmonary hypoplasia, and that there will be limitations to management using ECMO.

Extracorporeal membrane oxygenation for newborns with gastric rupture

Abstract Extracorporeal membrane oxygenation (ECMO) has been recognized to be beneficial to overcome not only persistent pulmonary hypertension of the newborn, but also cardiopulmonary distress due to neonatal sepsis. However, few papers have reported on the efficacy of ECMO for surgical sepsis in neonates with underlying diseases. This paper reports our experience with ECMO in three newborns with gastric rupture, one of the most serious causes of surgical sepsis in the neonatal period. Over the past 12 years, 14 newborns had gastric rupture; 3 developed lethal cardiopulmonary distress that conservative strategies, including aggressive intensive care, failed to manage, and were selected for ECMO. The clinical data of these patients were retrospectively analyzed. The onset time and duration of ECMO varied from 23 to 143 h of age and 72 to 294 h, respectively. In case 3, complicated by massive intra-abdominal hemorrhage during ECMO, anticoagulants were changed from heparin alone to combined use with nafamostat mesilate, a thrombin inhibitor with a very short half-life. Ultrafiltration or hemodialysis was added in two cases to regulate massive volume overload associated with renal failure. Despite major hemorrhagic complications in two cases, all patients survived. Thus, ECMO may be beneficial in managing neonates with therapy-resistant gastric rupture.