Accuracy of central venous pressure measurements in the inferior vena cava in the ventilated child

Murdoch IA, Rosenthal E, Huggon IC, Coutinho W, Qureshi SA. Accuracy of central venous pressure measurements in the inferior vena cava in the ventilated child. Acta Pædiatr 1994;83:512–14. Stockholm. ISSN 0803–5253
We compared central venous pressure measurements from three sites, superior vena cava, inferior vena cava and right atrium, in 12 children undergoing cardiac catheterization whilst on assisted ventilation. There was no significant difference between the mean pressures in the superior vena cava and the inferior vena cava. Furthermore, there was also no difference between the mean pressures in the inferior vena cava and the right atrium. Because of the greater safety of the placement of pressure monitoring lines in the inferior vena cava via the femoral vein, this approach should be the preferred route for central venous pressure monitoring in children.     

Cerebral tissue oxygenation index and superior vena cava blood flow in the very low birth weight infant

Background: Superior vena cava (SVC) flow assesses blood flow from the upper body, including the brain. Near infrared spectroscopy (NIRS) provides information on brain perfusion and oxygenation.
Aim: To assess the relationship between cerebral tissue oxygenation index (cTOI) and cardiac output measures in the very low birth weight (VLBW) infant in the first day of life.
Methods: A prospective observational cohort study. Neonates with birth weight less than 1500 g (VLBW) were eligible for enrollment. Newborns with congenital heart disease, major congenital malformations and greater than Papile grade1 Intraventricular Haemorrhage on day 1 of life were excluded. Echocardiographic evaluation of SVC flow was performed in the first 24 h of life. Low SVC flow states were defined as a flow less than 40 mL/kg/min. cTOI was measured using NIRO 200 Hamamatsu.
Results: Twenty-seven VLBW neonates had both echocardiography and NIRS performed. The median (range) gestation was 29/40 (25 + 3 to 31 + 5 weeks) and median birth weight was 1.2 kg (0.57–1.48 kg). The mean (SD) TOI was 68.1 (7.9)%. The mean (SD) SVC flow was 70.36(39.5) mLs/kg/min. The correlation coefficient of cerebral tissue oxygenation and SVC flow was r = 0.53, p-value 0.005. There was a poor correlation between right and left ventricular output and cTOI which is not surprising considering the influence of intra- and extracardiac shunts.
Conclusion: There is a positive relationship between cerebral TOI values and SVC flow in the very low birth infant on day one of life.     

The first report of a patient with interrupted inferior vena cava,multiple post-renal veins and azygos-hemiazygos continuation

The first case of a patient with interrupted inferior vena cava, four post-renal veins and an azygoshemiazygos continuation is presented. The complicated anomalies were omphalocele and atrial septal defect. Cine-magnetic resonance imaging and cardiac catheterization showed an anomalous retroaortic left innominate vein, azygos-hemiazygos continuation in the prerenal portion, arch formed renal vein in the renal portion and four embryonic vessels in the post-renal portion. Combination of these anomalies in the major venous system suggested that the inferior vena cava had failed to form and that the bilateral embryonic venous system, postcardinal and supracardinal veins persisted to be the systemic venous channels.     

Successful kidney transplantation in a small child with end‐stage renal disease due to angiotensin receptor blocker fetopathy and atretic inferior vena cava

Kidney transplantation is the treatment of choice in pediatric patients with end‐stage renal disease. This population presents technical challenges particularly in those less than 20 kg due to anomalous anatomy, vascular access issues prior to transplantation, and a generally small size for age. Standard allograft outflow is usually achieved utilizing the iliac veins or IVC. When use of the iliocaval system is not feasible, alternative anastomosis must be considered. Herein, we report a case of a pediatric kidney transplantation where successful allograft outflow was achieved using the SMV when he was found to have an atretic IVC intraoperatively. In this setting, use of the portal system was required to achieve adequate allograft outflow. We created a donor iliac graft for added length to anastomose the renal vein with the SMV. In the setting of IVC occlusion with poor drainage, we utilized a patent vessel with larger caliber for outflow to reduce the risk of high venous pressures, allograft failure, venous rotation, and thrombosis. We conclude that the SMV may serve as an alternative outflow tract in the small pediatric patient and provides the vessel caliber needed to reduce the risks of complications.     

The relationship between fetal inferior vena cava diameter pulse and flow velocity waveforms in normal and compromised pregnancies

BACKGROUND: The circulation is characteristically assessed by pressure and flow. OBJECTIVE: To evaluate the hemodynamic significance of fetal inferior vena cava (IVC) flow velocity waveform (FVW) indices in relation to the diameter pulse waveform (DPW). STUDY DESIGN: Doppler ultrasound and a phase locked loop echo tracking system were used to measure the FVW and the DPW in the fetal IVC, respectively. SUBJECTS: We studied 98 normal fetuses (20 to 40 weeks) and 65 compromised fetuses with increased umbilical placental resistance. RESULTS: The DPW consisted of four waves (A, X, V, and Y waves). Three components (systolic flow; S, diastolic flow; D, reverse flow; R during atrial contraction) were identified in the FVW. The FVW indices were examined in relation to the X descent {(A - X) / A%} of the DPW. The compromised group was divided into three subgroups by the X descent. In 15 fetuses the waveform was normal. In 32 there was a high pulsatile pattern with deep descent form the A crest to X trough. In 18 the X descent was shallow and the pulsatility appeared reduced. The high and low pulsatile patterns were associated with an increase in the S/D ratio and the R/S ratio, respectively. CONCLUSION: In fetal compromise the high pulsatility DPW may result from increased end-diastolic pressure in response to the increase in ventricular afterload caused by the placental vessel obliteration. The S/D ratio of the FVW may reflect the increasing cardiac afterload. The low pulsatility DPW may indicate depressed myocardial function and output. In the FVW, the R/S ratio may be associated with this.     

Search for the azygos: a lesson learnt from a case with left superior vena cava, esophageal atresia and tracheo-esophageal fistula

The azygos vein is of superior importance during the operation for esophageal atresia with tracheo-esophageal fistula (EA; TEF). Its location helps the surgeon to locate the fistula. Newborns with persistent left superior vena cava (LSVC) may have alterations in the location of the azygos, and since LSVC is not uncommon in EAs with fistulae, it is important to locate the azygos during a pre-operative echocardiogram. Foreknowledge of a possible absent azygos may avoid morbidity while trying to locate the fistula. We present a case of a newborn with EA, TEF, and LSVC in which the azygos vein was absent.     

Cerebral tissue oxygenation index,cardiac output and superior vena cava flow in infants with birth weight less than 1250 grams in the first 48 hours of life

Background

Near-infrared spectroscopy is a non-invasive method of assessing cerebral oxygenation. Functional echocardiography is increasingly used by neonatologists in the assessment of cardiovascular function.

Aims

To correlate cerebral tissue oxygenation index (cTOI) and cardiac output in infants less than 1250 g at 6, 12, 24 and 48 hours of age.

Study design

A prospective observational study.

Subjects

Newborns with birth weight < 1250 g.

Outcome measures

Serial assessments of superior vena cava (SVC) flow, right and left ventricular outputs, ductus arteriosus and cTOI were performed at 6, 12, 24 and 48 hours of age. Clinical parameters, including mean blood pressure, mean airway pressure, blood gas parameters and oxygen saturations were recorded.

Results

22 neonates were enrolled following parental consent. The mean birth weight was 851 g (SD ± 201), mean gestational age was 25.9 weeks (SD ± 1.7). Mean SVC flow at 6 hours of age was 56.8 ml/kg/min and increased to 68.6 ml/kg/min at 48 hours of age. 9 infants (41%) had at least one measurement of low SVC flow (< 41 ml/kg/min) in the first 48 hours. Mean cTOI was 65.2% at 6 hours of age, 63.9% at 12 hours of age, 68.8% at 24 hours of age and 67.2% at 48 hours of age. Cerebral fractional tissue oxygen extraction values were highest at 12 hours (0.31 ± 0.09). There was no correlation between SVC flow and cTOI values.

Conclusion

SVC flow, left and right ventricular output increased during first 48 hours of life. cTOI decreased at 12 hours of age with a concomitant increase in fractionated oxygen extraction. These changes reflect transitional changes in both cardiac and cerebral hemodynamics in extremely low gestational age newborns during the first 48 hours.     

Superior vena cava flow: Role,assessment and controversies in the management of perinatal perfusion

The superior vena cava (SVC) is a large vein responsible for the venous return of blood from structures located superior to the diaphragm. The flow in the SVC can be assessed with Doppler ultrasound and can be used as a proxy for cerebral perfusion. Early clinical research studies showed that low SVC flow, particularly if for a prolonged period, was associated with short term morbidity such as intraventricular hemorrhage, mortality, and poorer neurodevelopmental outcomes. However, these findings have not been consistently reported in more recent studies, and the role of SVC flow in early management and as a predictor of poor long-term neurodevelopment has been questioned. This paper provides an overview of SVC assessment, the expected range of findings, and reviews the role of SVC flow as a diagnostic and monitoring tool for the assessment of perinatal perfusion.     

Direct entry of the right superior vena cava into the left atrium with aneurysmal dilatation and stenosis at its entry into the right atrium with stenosis of the pulmonary veins: A rare case

Summary This is the first autopsied case reported in the English language literature wherein the right superior vena cava entered both atria with obstruction of the entry into the right atrium, aneurysmal dilatation of the proximal part of the superior vena cava, and entry of the stenosed right upper pulmonary vein into the aneurysmal sac. The aneurysmally dilated right superior vena cava communicated directly with the left atrium. In addition, the remainder of the pulmonary veins, all of which were markedly stenosed, entered the left atrium. The embryogenesis of this unique malformation is briefly discussed. Aided by grant HL 30558-01 from the National Heart, Lung and Blood Institute of the National Institutes of Health, Bethesda, Maryland.     

Combined split liver and kidney transplantation in a three‐year‐old child with primary hyperoxaluria type 1 and complete thrombosis of the inferior vena cava

Khan Z, Sciveres M, Salis P, Minervini M, Maggione G, Cintorino D, Riva S, Gridelli B, Emma F, Spada M. Combined split liver and kidney transplantation in a three‐year‐old child with primary hyperoxaluria type 1 and complete thrombosis of the inferior vena cava.
Pediatr Transplantation 2011: 15: E64–E70. © 2009 John Wiley & Sons A/S. Abstract: PH1 is an inborn error of the metabolism in which a functional deficiency of the liver‐specific peroxisomal enzyme, AGT, causes hyperoxaluria and hyperglycolic aciduria. Infantile PH1 is the most aggressive form of this disease, leading to early nephrocalcinosis, systemic oxalosis, and end‐stage renal failure. Infantile PH1 is rapidly fatal in children unless timely liver‐kidney transplantation is performed to correct both the hepatic enzyme defect and the renal end‐organ damage. The surgical procedure can be further complicated in infants and young children, who are at higher risk for vascular anomalies, such as IVC thrombosis. Although recently a limited number of children with IVC thrombosis have underwent successful kidney transplantation, successful multi‐organ transplantation in a child with complete IVC thrombosis is quite rare. We report here the interesting and technically difficult case of a three‐yr‐old girl with a complete thrombosis of the IVC, who was the recipient of combined split liver and kidney transplantation for infantile PH1. Although initial delayed renal graft function with mild‐to‐moderate acute rejection was observed, the patient rapidly regained renal function after steroid boluses, and was soon hemodialysis‐independent, with good diuresis. Serum and plasma oxalate levels progressively decreased; although, to date they are still above normal. Hepatic and renal function indices were at, or approaching, normal values when the patient was discharged 15‐wk post‐transplant, and the patient continues to do well, with close and frequent follow‐up. This is the first report of a successful double‐organ transplant in a pediatric patient presenting with infantile PH1 complicated by complete IVC thrombosis.     

Extended deep vein and inferior vena cava thrombosis in a 15-year-old boy: Successful lysis with recombinant tissue-type plasminogen activator 2 weeks after onset of symptoms

We present the case of a 15-year-old boy with thrombosis of the inferior vena cava, the femoral, inguinal, and renal veins of unknown origin. Although the thrombosis was 2 weeks old, thrombolytic therapy with recombinant tissue-type plasminogen activator (maximum dosage: 0.4 mg/kg/h) was started as this appeared to be the only change to re-establish normal kidney function. After 1 week, treatment was discontinued because of generalized bleeding. At this time, the infrarenal inferior vena cava was again patent with complete lysis of all other clots. Phlebography 3 months after lysis documented an abnormal renal vein, a tubular, subhepatical stenosis of the inferior vena cava and a large collateral vessel between the inferior vena cava and the azygos vein.     

Endovascular treatment of stenosis between hepatic vein and inferior vena cava following liver transplantation in a child: a case report

The liver transplantation technique advances have allowed the endovascular treatment of stenosis between hepatic vein and inferior vena cava, and this has become an established and widely acceptable method for the treatment of patients with end-stage liver disease. However, in spite of the advances in the surgical technique of liver transplantation there is relatively still a high incidence of postoperative complications, especially those related to vascular complications. One technical variant of orthotopic liver transplantation is the piggyback technique with conservation of the recipient vena cava, which is anastomosed to the graft hepatic veins. As a consequence of the increased number of liver transplants in children, there is a higher demand for endovascular treatment of vascular stenosis, such as those at the level of the hepatic veins. This leads to more consistent experience of endovascular treatment of the surgical vascular complications following liver transplantation. This article describes the case of a child submitted to liver transplantation with reduced graft (left lateral segment) who presented stenosis of the anastomosis between the hepatic vein and IVC 6 months later which was successfully treated by PTA.     

The correlation between preputial blood flow and microvessel density in distal hypospadias: A prospective clinical study

ObjectiveA prospective clinical study was designed to investigate the correlation between preputial blood flow (BF) and microvessel density (MVD).Patients and methodsA total of 44 children were included in the study. The hypospadias group consisted of 16 children undergoing distal hypospadias repair, and the control group consisted of 28 age-matched healthy children undergoing circumcision. BFs were measured using a laser Doppler flowmeter on the most distal part of the dorsal prepuces, and then the tissue samples were harvested from the same location. They were immunostained with an antibody against CD31 in order to assay MVD. The statistical analyses were carried out using Student's t test and Pearson's correlation analysis.ResultsThe preputial MVD was found to be significantly decreased in the patients with hypospadias compared with the healthy children (33.95 ± 9.79 vs. 48.25 ± 10.08; p < 0.05), whereas there was no difference in terms of the BF (40.58 ± 16.16 vs. 33.09 ± 19.65; p > 0.05).ConclusionsWe found no correlation between the preputial MVD and BF in the present study. This result suggests that reduced preputial MVD does not have any influence on BF in distal hypospadias.     

The relationship between serum creatinine,serum cystatin C and glomerular filtration rate in pediatric renal transplant recipients: a pilot study

Serum cystatin C more accurately reflects glomerular filtration rate (GFR) in pediatric renal transplant recipients than serum creatinine. Nineteen pediatric renal transplant recipients, 15 male and 4 female, ranging in age from 8.35 yr to 19.06 yr (median 13.52 yr), were enrolled in the study over an 18-month period. Twenty-eight measurements of 99mTc-DTPA GFR were compared with simultaneous measurements of serum cystatin C and Cr. Linear regression analysis, Pearson correlation coefficients and analysis of variance (anova) were used to determine the relationship between creatinine, cystatin C and GFR. The correlation coefficients (R2) for the relationship of 1/Cr to DTPA-GFR and for 1/cystatin C to DTPA-GFR were 0.63 and 0.58, respectively. There was no significant difference between serum cystatin C and serum creatinine as markers of GFR. Serum cystatin C, which costs more to measure than serum creatinine, offers no advantage in monitoring the renal function of pediatric renal transplant recipients.