Neonatal oxidative stress depends on oxygen blood pressure in umbilical artery

With advancing gestation, partial pressure of oxygen (pO2) and pH fall significantly. Hypoxia is a main factor inducing free radical generation and thereby oxidative stress (OS). Placental and fetal tissue response when oxygen becomes restricted is complex and partially known. We tested the hypothesis that changes in umbilical artery and vein blood gas concentrations modulate OS occurrence in the newborn. Seventy umbilical artery and vein plasma samples were collected from healthy term newborns immediately after delivery. F2 Isoprostanes (F2-Isop) were measured in all samples as reliable markers of lipid peroxidation. Significantly lower pCO2 and higher pO2 and pH were found in umbilical vein than in artery, as expected. A positive correlation was detected between pH and pO2 only in umbilical artery (p=0.019). F2-Isop levels were no different between artery and vein in cord blood. Significant correlations were found between F2-Isop and pCO2 (p=0.025) as well as between F2-Isop and pH in umbilical vein (p=0.027). F2-Isop correlated with pCO2 (p=0.007) as well as with pO2 values (p=0.005) in umbilical artery blood. Oxidative stress (OS) in newborns depends on oxygen concentrations in umbilical artery. OS biomarkers significantly correlate with pO2 and in umbilical artery but not in umbilical vein. In normoxic conditions fetal-maternal gas exchanges occurring in placenta re-establish normal higher oxygen levels in umbilical vein than artery, with a normal production of free radicals without any deleterious effects.

Early treatment with ursodeoxycholic acid for cholestasis in children on parenteral nutrition because of primary intestinal failure

BACKGROUND

There is conflicting evidence as to whether ursodeoxycholic acid (UDCA) reduces the incidence of parenteral nutrition-associated cholestasis.

AIM

To investigate the efficacy of UDCA on parenteral nutrition-associated cholestasis in children with intestinal failure due to short bowel syndrome or to other causes.

METHODS

Children with cholestasis received 30 mg/kg/day UDCA. Improvement or normalization of parenteral nutrition-associated cholestasis was evaluated at 6 months of therapy and at the last follow-up. In a subgroup of children, serum UDCA levels were measured while receiving UDCA and after 4 weeks withdrawal.

RESULTS

Twelve children were treated with UDCA. Full remission or partial improvement of parenteral nutrition-associated cholestasis occurred in 11 of 12 children. In three of four children, withdrawal of UDCA was associated with a rebound rise of cholestasis. Only one of 12 treated children showed no improvement and in this patient, in contrast to four other patients, plasma levels of UDCA did not increase during treatment.

CONCLUSIONS

Ursodeoxycholic acid was effective in controlling parenteral nutrition-associated cholestasis. The efficacy of UDCA also in children with short bowel is related to intestinal absorption.

[Current trend in the diagnosis and treatment of primary non refluxing megaureter]

BACKGROUND

The terms megaureter or hydroureteronephrosis are non-specific because indicate various pathologic entities recognise different causes (obstruction, reflux, obstruction-reflux, primary and secondary). An undeveloped renal function in neonatal period makes more difficult the therapeutic approach. Actually the problem is to find the indicators that consent us the individualization of patients more suitable for nonoperative management.

METHODS

From 1996 to 2002, we observed 60 patients with 74 megaureters. In 24 cases the diagnosis was antenatal, 6 cases were diagnosed immediately after birth, 13 in the first year of life and 17 after the first year (2y-10y). Patients were classified in two groups based on age; 43 cases diagnosed in the first year of life and 17 after. Both of them were classified in two further groups based on ureteral size and renal function, scintigraphically evaluated.

RESULTS

In the first group (A) ureters with 10 mm of dilatation improved in 38.9% of the cases. Were stationary 50% and impaired 11,1% of them. Ureters with dilatation between 7 and 10 mm improved in 24%, were stationary in 72% and impaired in in 4% of the cases. Ureters with less than 7mm dilatation improved in 35.2% and were stationary in 64.8%. In the group A renal scintigraphy MAG3 demonstrated, in the patients with acceptable renal function and washout, an improvement in 65% of the cases. Was stationary in 30% and impaired in 10%.

CONCLUSIONS

The grade of dilatation evaluated with ultrasonographic exam and the study of renal function with diuresis renal scintigraphy using Tc-99m MAG3 and washout grade with diuresis renal scintigraphy are remarkable markers for the treatment choice.

Laparoscopic solution of a vascular complication occurring during an open procedure in a child

Usually the word conversion implies conversion from a laparoscopic procedure to an open procedure to solve complications occurring during laparoscopy. In this article we report a conversion from an open procedure to a laparoscopic one, to treat a vascular complication that occurred during an orchiectomy performed in open surgery. A 2-year-old boy came to our center for a right orchiectomy. The clinical history of this baby showed the presence of a right atrophic testis positioned in the medial part of the inguinal canal, a finding also confirmed by ultrasonography. One of our residents performed a right orchiectomy via an open inguinal procedure. After removing the testis, and before ligating the inner spermatic vessels at the level of the internal inguinal ring, the forceps that held the vessels was inadvertently opened, causing a contraction of the spermatic vessels. Since we were unable to identify the vessels and achieve hemostasis via the inguinal opening, a conversion to laparoscopic surgery was decided. A 10-mm 0 degrees optics was introduced through an umbilical trocar and revealed a large retroperitoneal hematoma along both the inner spermatic vessels and the deferential vessels, for about 3-4 cm from the internal inguinal ring. Two 5-mm trocars were positioned in triangulation and hemostasis was achieved by positioning clips on the vessels at the level of internal inguinal ring and proximally to the hematoma. Surgery lasted 1 hour; the laparoscopic procedure, 25 minutes. The baby was discharged 2 days after surgery. At a 9-month follow-up the clinical and ultrasonographical evaluation was normal. This case clearly shows the usefulness of laparoscopy in pediatric surgery, as well as to solve complications due to open surgery. We think that nowadays the use of laparoscopy should be considered indispensable by every pediatric surgical team.

[Surgical treatment of pseudomembranous colitis. Considerations on a clinical case]

Pseudomembranous colitis is an uncommon pathology although the number of cases recorded has risen steadily over the past decades. It is closely correlated with antibiotic treatment and above all affects immunodepressed subjects. It is manifested by a wide variety of clinical symptoms, ranging from simple diarrhea to acute abdomen. The latter, although fortunately extremely rare, often requires surgical therapy.

[Hepatic hemangioma: diagnosis and treatment]

Cavernous hemangioma is the most common benign tumor of the liver. Most patients are asymptomatic and the tumor is discovered incidentally during diagnostics procedures, at laparotomy or at autopsy. Only 10% of hepatic hemangiomas reach dimensions that need surgical treatment. The role of surgical excision in their treatment has not been well defined. We report a careful examination of our casuistry and at the same time a study of the literature.