Effects of fluid resuscitation on cerebral tissue oxygenation changes in a piglet model of hemorrhagic shock.

BACKGROUND: Acute blood loss linked to severe hypovolemia and hemorrhagic shock is a critical condition in pediatric intensive care. This study was to investigate the role of various fluid resuscitation approaches to cerebral tissue oxygenation using a piglet model of hemorrhagic shock. METHODS: Thirty piglets received blood removal to induce hemorrhagic shock, and then were randomly assigned to a control group (no treatment), a control-normal saline (NS) group (treated with bolus normal saline 10 mL/kg only), or one of three treatment groups treated with 15 mL/kg/dose fluid every 30 min with either whole blood (WB), lactated Ringer's solution (LR), or NS in addition to an initial bolus of saline. The piglets' physiological profiles, arterial blood gases, and regional cerebral oxygen saturation (rScO(2)) levels were recorded, fractional tissue oxygen extraction was calculated, and blood hemoglobin levels were measured. RESULTS: The results showed that no matter whether treated with only one dose of bolus NS (control-NS group) or with extra WB, LR, or NS, all the treated animals had a significantly higher survival rate, mean arterial blood pressure (MAP), arterial oxygen tension, arterial oxygen saturation, and rScO(2) than the control group (p<0.05). Animals treated with WB all survived the full experimental period, and their hemoglobin levels, MAP, and rScO(2) were the highest comparing to all other groups (p<0.05). CONCLUSION: Effective resuscitation using a high concentration of inspired oxygen and adequate fluid infusion, either as a single-dose bolus of NS or combining this with a subsequent transfusion of WB, LR, or NS, helped to stabilize the cardiovascular condition of the tested young subjects and improved cerebral tissue oxygenation over the emergent first four hours. Furthermore, WB was the best fluid choice when used in addition to the bolus NS challenge for maintaining better brain tissue oxygenation when treating hemorrhagic shock.

Giant congenital melanocytic nevi in neonates: report of two cases.

Giant congenital melanocytic nevi are rare, with an estimated incidence of approximately 1 in 20,000 live births. They increase the lifetime risk for malignant melanoma and neurological deficits, including leptomeningeal melanocytosis and epilepsy. Recently, we encountered two patients in whom giant congenital melanocytic nevi were noted at birth. Case 1 presented with the largest nevus spreading across the posterior scalp, neck, chest wall, shoulder and upper back. At the age of 2 months, magnetic resonance imaging (MRI) was performed and no leptomeningeal melanocytosis was found. Case 2 presented with a huge nevus covering most parts of the lower abdomen, lower back, buttocks and bilateral upper thighs. She also had normal MRI findings in the newborn period. At the age of 7 years, leptomeningeal thickening on the surface of the junction between the pons and midbrain was found on brain MRI although she was neurologically asymptomatic. Here, we describe these two cases with congenital melanocytic nevi and review the literature about its clinical manifestations, outcomes, risks for malignant melanoma and neurocutaneous melanosis, and possible surgical interventions.

Peritoneal dialysis in infants and children after open heart surgery.

BACKGROUND: Infants and children who undergo surgical repair of complex congenital heart diseases are prone to developing renal dysfunction. The purpose of this study was to investigate the risk factors associated with prolonged peritoneal dialysis (PD) and the mortality of pediatric patients with acute renal failure (ARF) after open heart surgery. METHODS: From June 1999 to May 2007, a total of 542 children underwent open heart surgery for congenital heart disease. Fifteen (2.8%) experienced ARF and seven (1.3%) required PD. The clinical and laboratory variables were compared between the survivor and non-survivor groups of ARF patients that needed PD. RESULTS: The non-survivors (n=3, 43%) had a Longer cardiopulmonary bypass time (154+/-21 vs. 111+/-8 minutes, p=0.012) and longer aorta clamping time (92+/-40 vs. 66+/-15 minutes, p=0.010) than the survivors (n=4, 57%). Before the PD, the pH and base excess of the arterial blood gas analysis in the survivors was much higher than that non-survivors (7.30+/-0.04 vs. 7.16+/-0.10, p=0.039; -5.15+/-3.13 vs. -12.07+/-2.9mmol/L, p=0.031). Furthermore, the survivors had a shorter interval between the onset of ARF and the day the PD was begun (1.2+/-0.4 vs. 4.3+/-1.2 days, p=0.001), and shorter duration of PD (6.6+/-2.7 vs. 13.0+/-3.5 days, p=0.036) than non-survivors. CONCLUSION: Early intervention with PD is a safe and effective method for managing patients with ARF after open heart surgery. The cardiopulmonary bypass and aortic clamping duration, time of initiating PD, duration of the PD, sepsis, and relative complications may predict the prognosis of these patients.

Sizing of atrial septal defects by intracardiac echocardiography for device closures.

BACKGROUND: Transcatheter closure of a secundum atrial septal defect (ASD) has become an effective method for surgical treatment. In this study, we evaluated the feasibility and accuracy of intracardiac echocardiography (ICE) for sizing ASDs compared with conventional methods. METHODS: Between January 2004 and December 2006, 270 patients underwent transcatheter closure of secundum ASD by using septal occluders. For 142 patients, the procedure was guided by transesophageal echocardiography (TEE), and for 128 patients by ICE. We compared the maximal diameters of the ASDs obtained during angiocardiography, transthoracic echocardiography (TTE), ICE, and TEE with balloon-stretched sizes ascertained by using a sizing plate. RESULTS: ASD diameters measured with the sizing plate were significantly correlated with those measured with ICE (r = 0.963), TEE (r = 0.912), angiography (r = 0.88), and TTE (r = 0.85). The predicted stretched diameter of the ASDs, i.e. (nonstretched diameter measured with ICE x 1.07) + 3.23 mm, agreed well with that measured by using a sizing plate (Ri = 0.974). CONCLUSION: ASD diameters measured with ICE correlated with sizing-plate measurements better than those determined with TEE, angiography or TTE.

The clinical manifestations and risk factors of a delayed diagnosis of Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is an acute febrile vasculitis and may cause coronary artery abnormalities. Due to the higher incidence in Asian countries, most pediatricians in Taiwan are familiar with KD. However, there are still some patients being diagnosed 10 days after the onset of the illness and not receiving a highly effective therapy. In this study, we analyzed the risk factors and clinical manifestations of patients with a delayed diagnosis of KD. METHODS: A retrospective review was made of the medical records of the patients diagnosed with KD at our institution between January 1996 and December 2005. The patients were divided into 2 groups: early-diagnosis group (EDG: diagnosis was made within 10 days after the onset of the fever) and delayed-diagnosis group (DDG: diagnosis was made 10 days after the onset of the fever). RESULTS: Fourteen of a total of 78 children (17.9%) were grouped into the DDG group, and 64 into the EDG group. There were no statistical differences between the 2 groups in terms of age, gender, number of antibiotics used, day of the first medical visit, total days of skin rash, conjunctivitis, mucosa changes, lymphadenopathy or laboratory examinations except for the higher white blood cell count and serum immunoglobulin G level in the DDG group. The patients in the EDG group had a clustered onset of symptoms as compared to the DDG group with a dispersed and late onset of symptoms. There was a higher risk of coronary artery abnormalities in the DDG group than the EDG group (42.9% vs. 14.1%; p = 0.036), and in the patients with KD who were younger than 1 year (29.0% vs. 12.7%; p = 0.043). CONCLUSION: Patients with delayed diagnosis of KD were associated with higher risk of developing coronary arterial lesions. It is necessary to develop a diagnostic test for KD and provide more education to health care providers for early recognition of KD.

Cerebral oxygenation during hypoxia and resuscitation by using near-infrared spectroscopy in newborn piglets.

BACKGROUND: Hypoxic events and cardiac arrest may cause brain damage in critical infants. This study investigated cerebral tissue oxygenation and oxygen extraction in a piglet model of hypoxic events, cardiac arrest and effects of resuscitation. METHODS: For the hypoxia experiment, anesthetized newborn piglets were randomized to a hypoxia group (n = 8) with decreasing ventilatory rate to 0, and a control group (n = 8) with no hypoxic conditions. Regional cerebral tissue oxygen saturation (rScO2, detected by near-infrared spectroscopy) and oxygen saturation were recorded every 5 minutes for 100 minutes. Fractional cerebral tissue oxygen extraction (FTOE) was calculated as (arterial oxygen saturation [SaO2] - rScO2)/SaO2. For the resuscitation experiment, animals were grouped as hypoxia-no CPR (n = 4), control-no CPR (n = 4), and control-CPR (n = 4) after cardiac arrest. Standard cardiopulmonary resuscitation (CPR) was performed on the control-CPR group and observed for 30 minutes. RESULTS: Immediate and significant changes in rScO2, and gradual changes in FTOE were observed during the hypoxia experiment. In the resuscitation experiment, no significant differences in rScO2 were found between groups. However, the highest FTOE was observed in the control-CPR group. CONCLUSION: Noninvasive monitoring of rScO2 and evaluating FTOE changes during hypoxia and resuscitation may help clinicians evaluate brain tissue oxygenation and viability.

A common SCN5A polymorphism attenuates a severe cardiac phenotype caused by a nonsense SCN5A mutation in a Chinese family with an inherited cardiac conduction defect.

The SCN5A mutations have been associated with a variety of arrhythmic disorders, including type 3 long QT syndrome (LQT3), Brugada syndrome and inherited cardiac conduction defects. The relationship between genotype and phenotype in SCN5A mutations is complex. Some SCN5A mutations may cause death or severe manifestations in some people and may not cause any symptoms or arrhythmias in others. The causes of these unpredictable clinical manifestations remain incompletely understood. The molecular basis of a four-generation family with cardiac conduction abnormalities was studied and whether variants in the SCN5A gene could account for the cardiac phenotypic variability observed in this family was determined. A novel mutation (W1421X) of SCN5A was identified in a four-generation family with cardiac conduction abnormalities and several cases of sudden death. Most family members who carry this W1421X mutation have developed major clinical manifestations or electrocardiographic abnormalities, both of which became more prominent as the patients grew older. However, the 73-year-old grandfather, who carried both the W1421X and R1193Q mutations, had thus far remained healthy and presented with only subtle electrocardiographic abnormalities, whereas most of his offspring, who carried a single mutation (W1421X), had died early or had major disease manifestations. This observation suggests that the R1193Q mutation has a complementary role in alleviating the deleterious effects conferred by W1421X in the function of the SCN5A gene. This report provides a good model to explain the mechanism of penetrance of genetic disorders.

Subdural hemorrhage in a child with acute promyelocytic leukemia presenting as subtle headache.

Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemia (AML) and is rare in children (< 10% of childhood AML). It tends to bleed with disseminated intravascular coagulation (DIC) and intracranial hemorrhage complication is often fatal. We report a 12-year-old child with APL who suffered a subdural hemorrhage and initially presented with a subtle headache mistaken as the side effect of all-trans-retinoic acid (ATRA). Blood component therapy and a pediatric dosage of ATRA (25 mg/m2/day) combined with idarubicin as induction chemotherapy were administered in the first week, but the bleeding diathesis persisted and DIC profiles showed no improvement. The patient then developed photophobia, neck stiffness, and constant headache. Evidence of increased intracranial pressure (IICP) and persistent bleeding from previous venous puncture sites were also noticed clinically. DIC and life-threatening IICP were beyond control until the ATRA dosage was increased to adult levels (45 mg/m2/day). This case suggests that the ATRA dosage for pediatric APL patients must be modified according to clinical condition. Emergency brain imaging should be considered in APL patients with signs of IICP to distinguish intracranial lesions from ATRA complications.

Is urorectal septum malformation sequence a variant of the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association? Report of a case and a review of the literature.

UNLABELLED: The urorectal septum malformation sequence (URSMS) consists of multiple systems anomalies including ambiguous genitalia, the absence of a perineal opening, an imperforate anus, and urogenital, colonic and lumbosacral anomalies. We describe a 3-day-old female infant with characteristic URSMS and review its clinical manifestations, outcomes and putative pathogenesis. We also compare its characteristics with those of the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia (VATER) association. CONCLUSION: Although defects of the urorectal septum malformation sequence and the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association overlap, we believe that they are separate entities. Differentiating the urorectal septum malformation sequence from vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association is helpful to develop appropriate clinical investigations and search for the aetiology and pathogenesis of these diseases.