Rohit P. Rao

Mycoplasma hominis and Ureaplasma species brain abscess in a neonate.

We report an infant with a mixed Mycoplasma and Ureaplasma brain abscess who was successfully treated with intravenous doxycycline and erythromycin. Therapeutic concentrations of doxycycline were demonstrated in cerebrospinal fluid. This report is evidence of the potential for Mycoplasma and Ureaplasma to produce focal central nervous system infection, as well as meningitis, in neonates and that use of doxycycline can be efficacious in the therapy of such infections.

PHACES Association: A Vasculocutaneous Syndrome

PHACES association is a spectrum of anomalies that might occur in infants with large facial hemangiomas. Most infants with PHACES association have segmental hemangiomas of the head or neck. Cardiac and cerebrovascular anomalies might be the most important association, as they carry a significant risk of complications. This article summarizes the dermatologic, cardiac, and cerebral vascular findings in a cohort of infants diagnosed with PHACES association. All had large segmental facial hemangiomas and aortic arch abnormalities. Four of the five were not suspected of having arch obstruction prior to imaging studies because of the aberrant origin of both subclavian arteries, and 4/5 required either interventional or surgical repair for arch obstruction. In contrast to classic aortic coarctation, the aortic anomalies found in the cohort had unusually complex and unpredictable anatomic involvement. Cerebral vascular anomalies were identified in 5/5, and 2/5 had neurologic complications secondary to abnormal cerebral vascular supply. It is important for care providers to recognize this association that presents with a cutaneous stigma, as it is associated with potentially lethal and often unrecognized vascular anomalies. Earlier recognition of the associated vascular pathologies might enable preemptive treatments before potentially devastating and irreversible sequelae.

Measurement of Regional Tissue Bed Venous Weighted Oximetric Trends During Exercise by Near Infrared Spectroscopy

BackgroundCardiopulmonary exercise testing (CPET) is limited to children able to tolerate the equipment. Modification of instrumentation to reduce invasiveness will open CPET to a wider population. Near Infrared Spectroscopy (NIRS) devices measure regional oxyhemoglobin saturation (rSO2). We aim to predict anaerobic threshold (AT) during CPET using multiorgan NIRS monitoring.Methods and ResultsNineteen subjects were recruited. NIRS probes were placed on the forehead, para vertebral space, vastus lateralis, and deltoid muscle (rSO2 C, rSO2 R, rSO2 L and rSO2 A). rSO2 was recorded at six second intervals at rest, exercise, and through a five minute recovery period. The AT was computed using the v-slope method. AT was also predicted using NIRS data by identifying the inflection point of the rSO2 trends for all the four sites. AT can be estimated by the point of slope change of rSO2 R, rSO2 C and the four-site composite measure.ConclusionsMultisite NIRS monitoring of visceral organs is a potential predictor of AT. This allows for monitoring in all forms of exercise over a wide age range.

Cerebral Hemodynamics in the Presence of Decreased Systemic Venous Compliance in Patients with Fontan Physiology May Limit Anaerobic Exercise Capacity

Patients who have had the Fontan procedure report poor exercise performance. Fontan subjects can tolerate a higher level of sub maximal activity than might be anticipated from Vo2, suggesting a different mechanism of exercise limitation. Near-infrared spectroscopy (NIRS) provides a non-invasive, continuous method to monitor regional tissue oxygenation (rSO2) and thereby a window into regional oxygen supply–demand relationships. We hypothesized that Fontan patients would have altered rSO2 trends from normal population that might reflect the mechanisms of exercise limitation. All the patients without structural or acquired heart disease and Fontan patients were eligible for inclusion if they were ordered to undergo cardiopulmonary exercise testing (CPET). Four-site regional rSO2 were recorded continuously during exercise. The difference between the oxyhemoglobin saturation measured by pulse oximetry (Spo2) and NIRS (rSO2) was computed as the regional arterial–venous saturation difference (AVDO2). A total of 33 normal subjects and five Fontan subjects scheduled for CPET were recruited. None of the Fontan subjects had a fenestration of the conduit. In the cerebral circulation, the Fontan patients have a significantly higher initial slope of increasing AVDO2 compared with normals. After vAT, the AVDO2 slope is flat for Fontan patients (p = 0.02). There is also a substantially larger rebound of cerebral rSO2 than in normal subjects after QT (p < 0.0001). Reduced anaerobic exercise capacity in Fontan patients may be secondary to limitation of cerebral blood flow, secondary to low systemic venous compliance due to absence of a sub-pulmonary ventricle, and augmented hyperventilatory response during exercise.

Near-Infrared Spectroscopic Monitoring During Cardiopulmonary Exercise Testing Detects Anaerobic Threshold

Cardiopulmonary exercise testing (CPET) provides assessment of the integrative responses involving the pulmonary, cardiovascular, and skeletal muscle systems. Application of exercise testing remains limited to children who are able to understand and cooperate with the exercise protocol. Near-infrared spectroscopy (NIRS) provides a noninvasive, continuous method to monitor regional tissue oxygenation (rSO2). Our specific aim was to predict anaerobic threshold (AT) during CPET noninvasively using two-site NIRS monitoring. Achievement of a practical noninvasive technology for estimating AT will increase the compatibility of CPET. Patients without structural or acquired heart disease were eligible for inclusion if they were ordered to undergo CPET by a cardiologist. Data from 51 subjects was analyzed. The ventilatory anaerobic threshold (VAT) was computed on

Near Infrared Spectroscopy Describes Physiologic Payback Associated With Excess Postexercise Oxygen Consumption in Healthy Controls and Children With Complex Congenital Heart Disease

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Effect of Fontan Fenestration on Regional Venous Oxygen Saturation During Exercise: Further Insights Into Fontan Fenestration Closure

and respiratory quotient post hoc using the standard V-slope method. The inflection points of the regional rSO2 time-series were identified as the noninvasive regional NIRS AT for each of the two monitored regions (cerebral and kidney). AT calculation made using an average of kidney and brain NIRS matched the calculation made by VAT for the same patient. Two-site NIRS monitoring of visceral organs is a predictor of AT.

An apology or absolution for cerebral near-infrared spectroscopy: Can we get on the same wavelength?

Neonatal critical aortic stenosis is life threatening and requires intervention shortly after birth. Early percutaneous aortic valvuloplasty is generally considered to be an effective way to obtain reliable prograde flow. We describe the integrated use of hybrid, open surgical, and single ventricle rehabilitation techniques to successfully treat a neonate with borderline left-sided cardiac structures, who sustained a complication from balloon aortic valvuloplasty.