Disturbed cerebral circulation during opening of the venoarterial bypass bridge in extracorporeal membrane oxygenation.

PURPOSE: To describe the effects on cerebral blood flow velocity (CBFV) of intermittent opening of the venoarterial bridge (VA bridge) during venoarterial extracorporeal membrane oxygenation (VA-ECMO). STUDY DESIGN: Prospective study in 22 newborns during VA ECMO. CBFV was measured in the pericallosal artery by Doppler ultrasound. Changes in peak systolic flow velocity (PSV), end diastolic flow velocity (EDV) and time-averaged mean flow velocity (TAM) on day 1, 2, 3, and 5 and at low ECMO flow (50- 150 ml/min) were analyzed (mean percentage+/-standard deviation (t-tests, p<0.05)). Changes >25% were considered relevant. The relationship between changes in CBFV and ECMO flow rate (Pearson correlation, p<0.01) was studied. RESULTS: Opening of the VA bridge resulted in statistically significant and relevant decreases in PSV (35 +/- 18%), EDV (93 +/- 15%) and TAM (68 +/- 13%), persisting during the consecutive days of treatment. Smaller changes in CBFV at low ECMO flow were statistically significant and mostly relevant: PSV (15 +/- 7%), EDV (76 +/- 21%) and TAM (40 +/- 12%). Changes in CBFV were positively correlated to the ECMO flow. CONCLUSION: Use of the VA bridge results in significant and relevant ECMO flow-dependent changes in CBFV, persisting during the treatment. The VA bridge should be used in such a way as to allow regular unclamping to be omitted.

Preduodenal portal vein and malrotation: what causes the obstruction?

AIM AND METHOD: Preduodenal portal vein is a rare congenital abnormality, and occurs either as a single malformation, in association with other malformations or as part of "polysplenia" syndrome. Preduodenal portal vein has seldom been reported as a cause of intestinal obstruction, however corrective surgery is nearly always performed. We conducted a 25-year retrospective study in a single centre to investigate the cause of obstruction in patients with preduodenal portal vein. Furthermore, we reviewed the literature on preduodenal portal vein. RESULTS: Over a period of 25 years, preduodenal portal vein was diagnosed in five patients. The diagnosis was made during surgery performed because of symptoms of high intestinal obstruction. All five patients had intestinal malrotation as well and, in all patients, another cause for high intestinal obstruction than preduodenal portal vein was found. CONCLUSION: Preduodenal portal vein is mainly asymptomatic. It is often associated with other intestinal congenital abnormalities more likely to cause high intestinal obstruction. Therefore, the (paediatric) surgeon should always be alert for another associated cause of intestinal obstruction. Because of the potential for technical problems from preduodenal portal vein during surgery, it nevertheless should be on the surgeon's mind during surgery when the patient has high intestinal obstruction.

[A right-sided congenital diaphragmatic hernia masked by pneumonia]. / Een rechtszijdige congenitale hernia diaphragmatica gemaskeerd door een pneumonie.

A 1-day-old premature newborn (34 weeks and 6 days) presented with respiratory insufficiency due to a group B haemolytic streptococcal (GBS) pneumonia. She recovered after temporary treatment with mechanical ventilation and antibiotics. At the time of discharge there was a slight increased fogging on the right side of the chest X-ray, interpreted as residual pleural effusion. Three days later the patient was readmitted with respiratory failure and a need for respiratory support. A chest CT scan revealed a right-sided congenital diaphragmatic hernia (CDH) with a large part of the liver and intestine in the chest. The diaphragmatic defect was closed during a surgical procedure. After an uneventful recovery the patient was discharged in good clinical condition. The combination of delayed presentation of right-sided CDH and neonatal GBS infection occurs rarely but has been described. Its pathogenesis is still unclear.

Management of pediatric esophageal perforation.

Esophageal perforation is a serious complication necessitating immediate therapy. In a retrospective study we have evaluated the results in 13 children treated for esophageal perforation. Eleven of 13 perforations could be managed conservatively. In one child with extrapleural effusion, tube drainage was performed. The only death in this series occurred in a child who was brought for treatment after a 60-hour delay. Thoracotomy and multiple abscess drainage eventually proved unsuccessful. On the basis of our experience with children with esophageal perforation or with complications after esophageal atresia repair, we conclude that management of esophageal perforation in children differs substantially from therapy in adults and necessitates restrictive treatment guided by clinical symptoms.

[Simultaneous bilateral Wilms' tumors]. / Simultane bilaterale Wilms-Tumoren.

Wilms' tumors occur in 4-14% bilaterally, partially simultaneously, partially metachronously. Therefore in every case with Wilms' tumor the contralateral kidney has to be examined thoroughly too. 5 children of a series of 52 patients with Wilms' tumor showed simultaneous bilateral occurrence (9,6%). The radiological procedures and their importance in diagnosis of bilateral Wilms' tumor are discussed. The prognosis of simultaneous bilateral Wilms' tumors is much better than that of metachronous ones and almost the same as that of unilateral ones.

Surgical repair of congenital diaphragmatic hernia during extracorporeal membrane oxygenation: hemorrhagic complications and the effect of tranexamic acid.

Extracorporeal membrane oxygenation (ECMO) was incorporated in a strategy of delayed repair of congenital diaphragmatic hernia (CDH) and was used for preoperative stabilization in patients who were unresponsive to maximal conventional treatment. If ECMO was required for preoperative stabilization the diaphragmatic defect was repaired while the patient was on ECMO. In the early experience with this approach all patients suffered from bleeding complications. Therefore, we adopted the use of antifibrinolytic therapy with tranexamic acid (TEA) during and immediately after CDH repair on ECMO. The efficacy of TEA was studied in an unblinded study using historical controls by comparing the postoperative blood loss and the transfusion requirements of red blood cells (RBC) in patient groups treated without (n = 9) and with TEA (n = 10). Patients who received TEA had significantly less bleeding at the surgical site than patients not receiving TEA (57 v 390 mL, P = .005) and had significantly lower RBC transfusion requirements than patients not receiving TEA (1.13 v 2.95 mL/kg/h, P = .03). In the very first two patients of the TEA group we encountered fairly severe thrombotic complications. TEA may have contributed to those complications. Based on the authors' experience they conclude: (1) TEA is effective in reducing postoperative blood loss, hemorrhagic complications, and RBC transfusion requirements associated with CDH repair on ECMO. (2) TEA may be responsible for thrombotic complications. (3) The appropriate, empirically established, dosage and administration patterns of TEA for CDH repair during ECMO seem to be one bolus of 4 mg/kg TEA intravenously 30 minutes before the anticipated CDH repair and a continuous infusion of 1 mg/kg/h TEA during the 24 hours after CDH repair.

Remodeling of pulmonary arteries in human congenital diaphragmatic hernia with or without extracorporeal membrane oxygenation.

PURPOSE: The aim of this study was to describe in detail the perinatal developmental profile of the pulmonary vasculature in congenital diaphragmatic hernia (CDH) and to examine the potential beneficial effects of extracorporeal membrane oxygenation (ECMO) on the vascular morphology. Additionally the authors aimed to identify the differences in pulmonary vascular morphology among CDH cases according to the primary cause of death: either extreme lung hypoplasia (LH) or persistent pulmonary hypertension (PPH). METHODS: The authors studied autopsy sections from 30 high-risk CDH cases with respect to the pulmonary arteries in relation to gestational age (GA) and ECMO treatment. They were grouped into CDH-I: 20 cases with GA greater than 34 weeks who were not subjected to ECMO and CDH-II: 10 cases with GA greater than 34 weeks, who were subjected to ECMO for an average time of 237 hours. Five age-matched neonates who died from placental insufficiency or birth asphyxia without evidence of lung hypoplasia served as controls (CON). Medial and adventitial thicknesses of pulmonary arteries were measured in lung sections stained with Elastic van Gieson by 2 investigators blinded for the clinical data. Immunohistological staining with anti-alpha-smooth muscle actin (alpha-SMA) was performed to confirm the precise location of the arterial media before morphometry. CDH cases were subgrouped and compared according to the primary cause of death. Unpaired Student t test was used for statistics, with significant P value < or =.05. RESULTS: In CDH newborns, a significant increase in medial, adventitial, and total wall thickness was found in pulmonary arteries with an external diameter of less than 200 microm as compared with age-matched controls (P<.004, .0001, and .0009, respectively). ECMO-treated CDH newborns showed a significantly thinner arterial adventitia than CDH patients who did not receive this treatment (P<.0001), approaching normal values. However, the medial thickness remained increased. Morphometrically, no significant differences in CDH cases between patients dying of PPH or severe LH could be determined. CONCLUSIONS: (1) In CDH, there is failure of the normal arterial remodeling processes occurring in the perinatal period. (2) Pulmonary vascular morphology in CDH does not differ between the groups with lung hypoplasia or persistent pulmonary hypertension as primary cause of death. (3) Adventitial thinning of these arteries might be one of the mechanisms by which ECMO alters PPH in CDH cases.

The midline cervical cleft.

The midline cervical cleft is a rare congenital anomaly of the ventral neck. With reference to two patients with a midline cervical cleft, we discuss the clinical picture, the embryology, and the surgical treatment.

Recirculation in double lumen catheter veno-venous extracorporeal membrane oxygenation measured by an ultrasound dilution technique.

Recirculation is a limiting factor for oxygen delivery in double lumen catheter veno-venous extracorporeal membrane oxygenation (DLVV-ECMO). This study compares three different methods for the determination of the recirculation fraction during double lumen catheter veno-venous ECMO at ECMO flow rates of 150, 125, 100, 75, and 50 ml/kg.min in nine lambs: (1) an ultrasound dilution method, in which the change in ultrasound velocity in blood after injection of a saline bolus as a marker is used for determination of recirculation; (2) an SvO2 method using real mixed venous blood oxygen saturation, the gold standard, for determination of recirculation fraction; and (3) the CVL method, in which oxygen saturation of a blood sample of the inferior vena cava is considered to represent mixed venous oxygen saturation. In all methods, the recirculation fraction increased with increasing ECMO flow rate. The correlation coefficient between the ultrasound dilution method and the SvO2 method was 0.68 (p < 0.01); mean difference was -2.4% (p = 0.6). Correlation coefficient between the ultrasound dilution method and the CVL method was 0.48 (p < 0.01); mean difference was -18.1% (p < 0.01). The correlation coefficient between the SvO2 method and the CVL method was 0.51 (p < 0.01); mean difference was -15.7% (p < 0.01). The ultrasound dilution method is a useful method for measurement of the recirculation fraction in DLVV-ECMO and is easier to use than the other methods.

Long-gap esophageal atresia: experience with reconstruction in 25 patients.

In a series of 183 patients with esophageal atresia in a period of 20 years, 25 had a "long-gap" esophageal atresia. In most of these cases we succeeded in saving the patients' own esophagus but at the cost of one to two years of intensive treatment. The overall survival was 80%. The result compares favorably with the results of esophageal replacement reported in the literature.

[Dumping syndrome in a child with an incorrectly positioned gastrostomy catheter]. / Dumpingsyndroom bij een kind met een verkeerd gelegen gastrostomiekatheter.

A 13-month-old girl experienced an epileptic fit due to hypoglycaemia. She was born with a posterolateral diaphragm defect and at the age of 1.5 months had undergone a Nissen fundoplication with which a gastrostomy was also performed. The tip of the gastrostomy catheter was found to be lying in the bulbus duodeni. Once this had been pulled back, the patient made a good recovery. Dumping syndrome is usually the result of a quicker gastric emptying time or a smaller gastric capacity, and in children it is mostly due to a Nissen fundoplication. In patients fed by tube who exhibit symptoms of dumping syndrome, the position of the feeding tube must be checked before other diagnostic or therapeutic steps are undertaken.

[Results of extracorporeal membrane oxygenation in 100 newborns with cardiorespiratory insufficiency]. / Resultaten van extracorporele membraanoxygenatie bij 100 pasgeborenen met cardiorespiratoire insufficiëntie.

OBJECTIVE: To describe the results of treatment with extracorporeal membrane oxygenation (ECMO) in newborns with severe cardiorespiratory insufficiency. DESIGN: Prospective, descriptive. METHODS: For all 100 newborns treated with ECMO in 1989-1997 in the Academic Hospital Nijmegen, department of Neonatology, the Netherlands, indications for treatment, complications during treatment and mortality within 6 weeks after cessation of ECMO were registered. RESULTS: The 100 children comprised 66 boys and 34 girls, with a mean age of 2 days (range: 1-15). Indications for ECMO treatment were: meconium aspiration syndrome: 39 with 37 survivors (95%), congenital diaphragmatic hernia: 31 with 23 survivors (74%), sepsis or pneumonia: 20 with 14 survivors (70%) and 'others' among which persistent pulmonary hypertension of the newborn: 10 with 8 survivors (80%). Eighteen children died (18%). Causes of death were rebound pulmonary hypertension (9 times), intracranial haemorrhage (4), multi-organ failure (3) and pulmonary problems (2). The most important complications during treatment were bleeding problems (29), clotting problems (20) and infections (11).

[Esophageal varices and portal hypertension in children; experiences with Vossschulte's method of dissection ligature]. / Oesophagusvarices en portale hypertensie bij kinderen; ervaringen met de dissectieligatuur volgens Vossschulte.

The optimal treatment of esophageal varices in childhood is an unresolved issue. Despite numerous studies concerning this topic, there seems to be no completely satisfying solution. An open and functioning portasystemic shunt provides a high degree of protection against esophageal variceal bleeding. However, technical obstacles imposed by the size of vessels available for shunting, reluctance to remove the spleen in a child and abnormalities of the portal vein often preclude successful portasystemic shunting in children. Therefore, a two-stage management has been proposed for the treatment of esophageal varices in childhood. In this approach Vossschulte's dissection-ligature has been utilized as a temporizing procedure. This operation has to bridge the time, until a decompressive shunt can be accomplished. Nine children with esophageal varices were treated by the dissection-ligature. There was no operative mortality. One patient succumbed during the follow-up period. One patient had a recurrent bleeding after 2 2/12 yrs, and underwent a shunting procedure at that time. Three patients had an esophageal stricture and swallowing difficulties. They were without complaints after a few dilatations. Data obtained from this study and from the literature indicate, that the dissection-ligature is safe and effective in controlling esophageal variceal bleeding. The dissection-ligature satisfies as temporary measure in the proposed two-stage management. Since many patients did not have any new bleeding-episodes and did not need any further surgery as well, it may be suggested that the dissection-ligature is not only suitable for temporary treatment, but also for permanent treatment. The dissection-ligature of Vossschulte should be kept in mind, if one is forced to consider a 'direct operation' of esophageal varices.

[Developments in management of esophageal atresia]. / Oesophagusatresie uit de kinderschoenen.

The results of treatment of oesophageal atresia show that attentiveness and knowledge of the referring paediatrician concerning diagnostics, preoperative care and transport, together with concentration of high-standard care and specific experience in centres for paediatric surgery, can lead to a substantial decrease in morbidity and mortality. Between 1955 and 1968 a total of 193 children have been operated for oesophageal atresia. Mortality has declined from 51% in the period 1955-1969 to 10% in the timespan 1980-1986. Mortality is almost solely determined by additional congenital malformations, in which congenital heartdefects form the major cause. Management of oesophageal atresia seems to have evolved to a routine-procedure. New trends in paediatric surgery pose new sorts of specific problems, that require attention.

[Gastroesophageal reflux]. / Gastro-oesofageale reflux.

Gastro-oesophageal reflux (GER) in children, causes sometimes aspecific symptoms in children. Not only in the case of regurgitation but also in respiratory problems or even in the 'near missed' - Sudden Infant Death Syndrome GER is to be considered. The most important method of investigation is pH-monitoring during 24 hours preceded by a barium meal and followed by endoscopy, in most cases. Operative treatment is necessary for a hiatal hernia, or after failure of conservative treatment of an oesophagitis. In mentally retarded children, who continue to vomit, a fundoplication can be necessary to improve general care.

Reliability of the acetylcholinesterase (ACE) reaction in rectal mucosal biopsies for the diagnosis of Hirschsprung's disease.

The ACE reaction in superficial rectal biopsies is a valuable diagnostic procedure for Hirschsprung's disease. Although the literature mentions a reliability as high as 100 percent accuracy, a false negative ACE reaction can occur. So the result of the histochemical examination can never be seen apart from the clinical picture. This paper deals with false-negative ACE reactions in 3 children. A false-negative ACE reaction is suggested to be caused by a developmental disturbance in the 6th or 7th embryonal week. Since this disturbance can be responsible also for an aganglionosis of the total colon and a part of the ileum, the chance of a false negative ACE reaction is postulated to be increased in an extensive aganglionosis in precisely those cases which are already a diagnostic challenge for the clinician.