Noninvasive Cerebral Oximeter as a Surrogate for Mixed Venous Saturation in Children

We evaluated the relationship between regional cerebral oxygen saturation (rSO₂) measured by near-infrared spectroscopy (NIRS) cerebral oximeter with superior vena cava (SVC), inferior vena cava (IVC), right atrium (RA), and pulmonary artery (PA) saturation measured on room air and 100% inspired oxygen administered via a non-rebreather mask (NRB) in children. Twenty nine pediatric post-orthotopic heart transplant patients undergoing an annual myocardial biopsy were studied. We found a statistically significant correlation between rSO₂ and SVC saturations at room air and 100% inspired oxygen concentration via NRB (r = 0.67, p = 0.0002 on room air; r = 0.44, p = 0.02 on NRB), RA saturation (r = 0.56, p = 0.002; r = 0.56, p = 0.002), and PA saturation (r = 0.67, p < 0.001; r = 0.4, p = 0.03). A significant correlation also existed between rSO₂ and measured cardiac index (r = 0.45, p = 0.01) and hemoglobin levels (r = 0.41, p = 0.02). The concordance correlations were fair to moderate. Bias and precision of rSO₂ compared to PA saturations on room air were −0.8 and 13.9%, and they were 2.1 and 15.6% on NRB. A stepwise linear regression analysis showed that rSO₂ saturations were the best predictor of PA saturations on both room air (p = 0.0001) and NRB (p = 0.012). In children with biventricular anatomy, rSO₂ readings do correlate with mixed venous saturation.     

Cerebral Near-Infrared Spectroscopy Correlates to Vital Parameters During Cardiopulmonary Bypass Surgery in Children

Near-infrared spectroscopy (NIRS) can monitor changes in cerebral regional oxygen saturation (rSO₂) and tissue hemoglobin content (HbT). The relation between cerebral NIRS readings and vital parameters has not been analyzed before at a fine temporal scale. This study analyzed this relation during cardiopulmonary bypass (CPB) surgery in 10 children (0–9 years, 1,770 min of data records) by using a novel random-coefficient model. The analysis indicated that a small number of patients is sufficient for obtaining significant results with this model. Changes of vital parameters explained 84.7 % of rSO₂ changes and 90.7 % of HbT changes. Cerebral rSO₂ correlated positively with perfusion pressure and inversely with body temperature (P < 0.05). Cerebral HbT correlated positively with perfusion pressure, central venous pressure, and temperature and inversely with arterial oxygen saturation (P < 0.05). During hypothermic circulatory arrest, the half-life of the exponential rSO₂ decay correlated to the rSO₂ reserve (P = 0.016). In conclusion, NIRS readings of cerebral hemoglobin content and tissue oxygen saturation correlate well to vital parameters during CPB surgery in children. NIRS may therefore become a monitoring device for the neuroprotective optimization of those vital parameters.     

Echocardiographic Assessment of Right Atrial Pressure in a Pediatric and Young Adult Population

Right atrial pressure (RAP) reflects right-sided cardiac hemodynamics and is useful in management of patients with cardiac and systemic disease. Studies in older adults demonstrated that inferior vena cava (IVC) diameter, IVC collapsibility index, hepatic vein systolic filling fraction (SFF), and right atrial volume (RAV) correlated with mean RAP at catheterization. This study aimed to assess the utility of echocardiographic parameters for assessment of RAP in children and young adults. Patients with pulmonary hypertension or heart transplantation undergoing right heart catheterization were recruited for this prospective observational pilot study. Transthoracic echocardiographic assessment of RAP was performed simultaneously with catheterization. For each parameter, three consecutive cardiac cycles were recorded. Long- and short-axis images of the IVC were obtained. RAV was assessed by area–length and biplane methods. IVC diameters and RAV were indexed to body surface area (BSA)^0.5 and (BSA)^1.4, respectively. Relationships between echocardiographic parameters and mean RAP were correlated using “Pearson’s r.” Fifty subjects aged 0.3–23 years (median 13, mean 12.3 ± 7 years) were enrolled. Mean RAP correlated modestly with RAV (r = 0.51, p < 0.001). Long-axis IVC_max (r = 0.30, p < 0.05) and tricuspid E wave velocity (r = 0.36, p < 0.01) also correlated with mean RAP. RV free wall tissue Doppler velocities, IVC collapsibility index, and hepatic vein SFF had no relation to mean RAP. In a pediatric and young adult population with pulmonary hypertension or heart transplantation, echocardiographic assessment of RAV and long-axis IVC_max provided a reasonable estimate of mean RAP. IVC collapsibility index and hepatic vein SFF demonstrated no association with mean RAP.     

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

Fontan fenestration closure is a topic of great debate. The body of data regarding the risks and benefits of fenestration closure is limited yet growing. Previous studies have demonstrated that Fontan patients have less exercise capacity than those with normal cardiovascular anatomy. Differences also have been noted within various subgroups of Fontan patients such as whether Fontan is fenestrated or not. This study aimed to compare trends in regional oxygen saturations using near-infrared spectroscopy (NIRS) in patients with Fontan circulations during ramping exercise to further delineate differences between patients with and without a fenestration. It was hypothesized that Fontan patients with fenestrations have better exercise times, higher absolute regional oxygen venous saturations, and smaller arteriovenous differences than Fontan patients without fenestrations. For this study, 50 consecutive Fontan patients and 51 consecutive patients with normal cardiovascular anatomy were recruited. Placement of NIRS probes was performed to obtain regional oxygen saturations from the brain and the kidney. Readings were obtained at 1-min intervals during rest, exercise, and recovery. A standard Bruce protocol was used with a 5-min recovery period. Absolute regional tissue oxygenation values (rSO₂) and arterial-venous oxygen saturation differences (AVDO₂) calculated as arterial oxygen saturation (SPO₂)—rSO₂ for normal versus Fontan patients and for fenestrated versus unfenestrated Fontan patients were compared using independent t tests. When normal and Fontan patients were compared, the Fontan patients had a significantly shorter duration of exercise (9.3 vs 13.2 min; p < 0.001). No statistically significant difference in rSO₂ change or AVDO₂ was evident at the time of peak exercise, at 2 min into the recovery, or at 5 min into the recovery. A small oxygen debt also was paid back to the brain in the Fontan patients after exercise, as evidenced by a narrower AVDO₂ than at baseline. The comparison of Fontan patients with and without fenestration showed no statistically significant difference in exercise time, rSO₂ change, or AVDO₂. The Fontan patients were noted to have shorter exercise times than the normal patients and also appeared to have an alteration in postexertional regional blood flow. However, when the various Fontan subtypes were compared by presence or absence of a fenestration, no significant differences were noted with regard to change in regional oxygen saturation or arteriovenous oxygen saturation. Thus, for patients with Fontan physiology, closure of the fenestration does not seem to have an impact on the dynamics of regional oxygen extraction during exercise or recovery.     

Renal Function of Patients with a Failing Fontan Circuit Undergoing Total Cavopulmonary Revision Surgery

This report characterizes renal dysfunction after total cavopulmonary (TCPC) revision surgery for atriopulmonary Fontan (APF) circulations, a known risk factor for a poor outcome. The perioperative data for 23 consecutively identified patients were reviewed. The preoperative mean glomerular filtration rate (GFR) was 101 ± 30 ml/min/1.73 m², decreasing to 65 ± 41 ml/min/1.73 m² early in the postoperative period. The preoperative GFR was highly correlated with age at APF (r = −0.5; p = 0.024), age at TCPC (r = −0.5; p = 0.01), and mixed venous saturation (r = 0.6; p = 0.01). Three of four patients requiring renal replacement therapy (RRT) died at a median age of 3 months (range, 18 days to 9 months). Determinants of early GFR and RRT were preoperative GFR (p = 0.016) and creatinine (p = 0.035). Younger age at primary Fontan (p = 0.008), higher preoperative mixed venous saturation (p = 0.019), and higher preoperative blood pressure (p = 0.006) independently predicted better GFRs at the latest follow-up evaluation. Renal function declines acutely after TCPC revision, often necessitating RRT. A requirement for RRT marks greater mortality. Higher preoperative creatinine levels identify those at greatest risk.     

Comparison of Calculated with Measured Oxygen Consumption in Children Undergoing Cardiac Catheterization

Our objective was to compare calculated (LaFarge) with measured oxygen consumption (VO₂) using the AS/3 TM Compact Airway Module M-CAiOVX (Datex-Ohmeda, Helsinki, Finland; AS/3 TM) in children without cardiac shunts in a prospective, observational study. VO₂ was determined at the end of the routine diagnostic and/or interventional catheterization. VO₂ was calculated according to the formula of LaFarge and Miettinen for each child and compared with the measured VO₂. Data were compared using simple regression and Bland Altman analysis. Fifty-two children aged from 0.5 to 16 years (median, 6.9 years) and weighing 3.4 to 59.4 kg (median, 22.9 kg) were investigated. Calculated VO₂ values ranged from 59.0 to 230.8 ml/min, and measured VO₂ values from 62.7 to 282.2 ml/min. Comparison of calculated versus measured VO₂ values revealed a significant correlation (r = 0.90, p < 0.0001). Bias and precision were 8.9 and 48.3 ml/min, respectively (95% limits of agreement: −39.4 to 57.2 ml/min). Comparison of calculated VO₂ in children older than 3 years (n = 41), as restricted to the formula, with measured VO₂, revealed a slightly reduced correlation (r = 0.86, p < 0.0001). Bias and precision were 10.0 and 52.5 ml/min, respectively (95% limits of agreement: –42.4 to 62.5 ml/min). We conclude that calculation of VO₂ by the LaFarge formula does not provide reliable values compared to measured values. In clinical routine, measured rather than calculated VO₂ values should be used for the estimation of cardiac output and related variables.     

Combined Cerebral and Renal Near-Infrared Spectroscopy After Congenital Heart Surgery

The maintenance of an adequate oxygen supply to tissues after congenital heart surgery is essential for good outcomes. The objective of this study was to assess the usefulness of near-infrared spectroscopy (NIRS) for estimating central venous oxygen saturation (ScvO₂) using both cerebral and renal measurements, explore its relation with cardiac output measurements and check its ability to detect low cardiac output. A prospective observational pilot study was conducted in patients weighing <10 kg undergoing cardiopulmonary bypass surgery. Spectroscopy probes were placed on the forehead and renal area, and serial cardiac output measurements were obtained by femoral transpulmonary thermodilution over the first 24 h after surgery. In the 15 patients studied, ScvO₂ was correlated with cerebral (r = 0.58), renal (r = 0.60) and combined (r = 0.71) measurements. Likewise, the systolic index was correlated with the NIRS signals: cerebral (r = 0.60), renal (r = 0.50) and combined (r = 0.66). Statistically significant differences were found in the NIRS measures registered in the 29 low cardiac output events detected by thermodilution: cerebral: 62 % (59–65) versus 69 % (63–76); renal: 83 % (70–89) versus 89 % (83–95); and combined 64 % (60–69) versus 72 % (67–76). In our series, combined cerebral and renal monitoring was correlated with central venous oxygen saturation and cardiac output; low cardiac output detection associated a different spectroscopy pattern.     

Barriers to medication adherence in children,adolescents, and young adults prescribed anticoagulation

Pediatric and adolescent and young adult (AYA) thromboembolism is treated with anticoagulation, but little is known about adherence. The aims of this study were to describe barriers to adherence among children and AYAs (ages 0–25 years) prescribed anticoagulants and to explore the relationship between barriers and self-reported adherence. Nearly 75% of patients and caregivers reported barriers, and a larger number of barriers was associated with missing at least one dose in the past month per both patient (r_pb = 0.48, p = .01) and caregiver (r_pb = 0.52, p = .01) report. Limitations, clinical implications, and future directions are discussed.     

Splanchnic Near-Infrared Spectroscopy and Risk of Necrotizing Enterocolitis After Neonatal Heart Surgery

Infants with critical congenital heart disease, especially patients with a single-ventricle (SV) physiology, are at increased risk for the development of necrotizing enterocolitis (NEC). Decreased splanchnic oxygen delivery may contribute to the development of NEC and may be detected by regional oximetry (rSO₂) via splanchnic near-infrared spectroscopy (NIRS). This prospective study enrolled 64 neonates undergoing biventricular (BV) repair or SV palliation for CHD and monitored postoperative splanchnic rSO₂ before and during initiation of enteral feedings to determine whether changes in rSO₂ are associated with risk of NEC. Suspected or proven NEC was observed in 32 % (11/34) of the SV subjects and 0 % (0/30) of the BV subjects (p = 0.001). Compared with the BV subjects, the SV palliated subjects had significantly lower splanchnic rSO₂ before and during initiation of enteral feedings, but the groups showed no difference after correction for lower pulse oximetry (SpO₂) in the SV group. The clinical parameters were similar among the SV subjects with and without NEC except for cardiopulmonary bypass times, which were longer for the patients who experienced NEC (126 vs 85 min; p = 0.03). No difference was observed in splanchnic rSO₂ or in the SpO₂–rSO₂ difference between the SV subjects with and without NEC. Compared with the patients who had suspected or no NEC, the subjects with proven NEC had a lower average splanchnic rSO₂ (32.6 vs 47.0 %; p = 0.05), more time with rSO₂ less than 30 % (48.8 vs 6.7 %; p = 0.04) at one-fourth-volume feeds, and more time with SpO₂–rSO₂ exceeding 50 % (33.3 vs 0 %; p = 0.03) before feeds were initiated. These data suggest that splanchnic NIRS may be a useful tool for assessing risk of NEC, especially in patients with an SV physiology.     

Echocardiographic Measurement of Epicardial Adipose Tissue in Obese Children

The echocardiographic measurement of epicardial adipose tissue (EAT) has been suggested as an easy method for evaluation of the visceral adipose tissue and its related cardiovascular risks in adults. However, a direct effect of obesity on cardiac function is not well established, and echocardiographic EAT thickness has not been studied in children. The aims of this study were to evaluate cardiac function and echocardiographic EAT thickness and to correlate EAT with the other echocardiographic findings in obese children. The study population included 106 obese and 62 lean children. Echocardiographic indexes of systolic and diastolic function were obtained. We measured EAT thickness on the free wall of the right ventricle from parasternal long-axis views. The septal and posterior wall thicknesses, relative wall thickness, left atrial diameter, and left ventricular mass were increased (p = 0.001) in obese children. However, systolic and diastolic functions of the left ventricle were normal in the patients. The obese children had a significantly thicker EAT (p = 0.001) compared to the lean subjects. EAT thickness correlated significantly with body mass index (r = 0.50, p = 0.001), left atrial diameter (r = 0.37, p = 0.001), and left ventricular mass (r = 0.33, p = 0.001). In conclusion, the present study demonstrates a close relationship between EAT thickness and obesity in children. Assessment of EAT thickness in routine echocardiographic examinations might be used as a feasible and reliable method for the evaluation of obesity and its related cardiovascular risks during childhood.     

The Use of High-Resolution Computed Tomography in the Evaluation of Pulmonary Hemodynamics in Patients with Congenital Heart Disease: In Pulmonary Vessels Larger Than 1 mm in Diameter

High-resolution computed tomography (HRCT) was carried out in 36 patients with congenital left-to-right shunt disease and 10 normal control subjects to assess the feasibility of CT in the evaluation of pulmonary hemodynamics. The patients had a left-to-right or a bidirectional shunt and the hemodynamic data obtained by cardiac catheterization in these patients were compared to the information obtained by CT imaging. The pulmonary/systemic blood flow (Q _p/Q _s) ratio and pulmonic/systemic resistance (R _p/R _s) ratio had a significant correlation with the pulmonary artery/bronchus (PA/Br) ratio (r= 0.54 and r=−0.37, respectively) and pulmonary vein/bronchus (PV/Br) ratio (r= 0.66 and r=−0.66, respectively), and the R _p/R _s and mean PA pressure also showed a significant correlation with the PA/PV ratio (r= 0.53 and r=−0.61, respectively) in the mid-lung field when accompanying bronchi were 4.0–5.9 mm in diameter. There was no correlation between the hemodynamic data and the size of the central and hilar PA or with the rate of PA tapering. With HRCT, it is possible to evaluate pulmonary hemodynamics in patients with congenital heart disease with a left-to-right or bidirectional shunt, particularly R _p/R _s and mean PA pressure, which have been very difficult to obtain noninvasively. The small-sized pulmonary vessel/Br ratio or the small-sized PA/PV ratio could offer very useful information, but the dimension of the central PA provided the least useful information.     

Heart Rate Variability and Atria Function in Children at Late Follow-Up Evaluation After Atrioventricular Node Slow-Pathway Radiofrequency Ablation

This study was designed to assess the changes in the conductive system, autonomic dysfunction, and global and regional function of the atria and ventricles in children late after slow-pathway radiofrequency ablation (RFA). The study enrolled 22 children, who has successfully undergone RFA 2 to 5 years previously (RFA group) and 20 healthy children (control group). Electrophysiologic study was performed for the RFA group. Holter monitoring and echocardiography were performed for all the children. At a late follow-up assessment, the RFA children were free of paroxysms, whereas 8 of the 22 children (36%) reported transient palpitations. Both mean and maximal heart rates (HR) were significantly increased, whereas indices of HR variability (% of succesive normal sinus RR intervals exceeding 50 ms [pNN50], root mean square of the succesive normal sinus RR interval difference [rMSSD], high-frequency component [HFC]) were significantly decreased in the RFA group compared with preablation and control data. Left atrial (LA) and right atrial (RA) volumes were significantly higher, and atria deformation indices were significantly lower in the RFA group. Correlations were found between the mean HR and the volumes of LA (r = 0.477; p < 0.001) and RA (r = 0.512; p < 0.001). A negative correlation between the maximal LA volume and the longitudinal strain rate (SR) during relaxation (r = –0.476; p = 0.03) and a positive correlation between the minimal LA volume and both longitudinal SR (r = 0.361; p = 0.03) and strain (ε) (r = 0.375; p = 0.024) during contraction were shown. These data suggest a possible link between atrial dysfunction and the hyperadrenergic state after RFA.     

Predicting children's fussiness with vegetables: The role of feeding practices

Vegetables are commonly rejected by children, making it is important to consider factors that are associated with children's fussiness with vegetables. The current study aimed to investigate whether fussiness with vegetables is associated with a number of factors including caregiver and child vegetable consumption; caregivers' general feeding practices; and caregivers' vegetable‐specific feeding practices. Caregivers (N = 297) of preschool children completed questionnaire measures of their child's fussiness with vegetables, as well as several caregiver and child factors hypothesised to be associated with children's fussiness with vegetables. Findings indicate that children who are fussier with vegetables consume a smaller quantity of vegetables and that almost all have caregivers who eat a smaller quantity of vegetables. Children's fussiness with vegetables was not significantly related to any general feeding practices used by caregivers. However, children's fussiness with vegetables was significantly associated with the use of several vegetable specific feeding practices. Caregivers of fussier children used more encouragement/pressure to eat with vegetables (r = 0.14, p = .01), hid vegetables within other foods more often (r = 0.30, p = <.01), used more food rewards for vegetable consumption (r = 0.19, p <.01), more other rewards for vegetable consumption (r = 0.21, p < .01), and compromised more when feeding vegetables (r = 0.14, p = .01). These findings suggest that rather than caregivers' general feeding practices being related to children's fussiness with vegetables, the specific feeding practices used when vegetables are rejected are more significant. It may therefore be helpful to develop advice for caregivers about which feeding practices to avoid when faced with a child who is fussy about eating vegetables.     

Cardiovascular Risk Factors and Carotid Intima-Media Thickness in Asymptomatic Children

Atherosclerosis, beginning in childhood, is dependent on several risk factors and may be predictive of coronary artery disease in adulthood. The risk factors for subclinical atherosclerosis are similar to those for clinical disease. Carotid intima-media thickness is a measure of subclinical atherosclerosis and a predictor of subsequent vascular events. This study aimed to examine the relationships of carotid intima-media thickness with known risk factors in asymptomatic children. Family history of cardiovascular disease was collected, together with anthropometric, demographic, and clinical data. Body mass index z-scores were calculated. Serum glucose, lipid fractions, fibrinogen, and C-reactive protein were determined. High-resolution ultrasonography was used to assess intima-media thickness. Associations and relationships of risk factors with composite intima-media thickness were explored. The study enrolled 93 children (44 girls) ranging in age from 49 to 169 months. The boys had a thicker intima-media (0.46 ± 0.06 mm) than the girls (0.43 ± 0.06 mm; p = 0.028). The unadjusted triglyceride levels were significantly higher in the overweight and obese children (p = 0.010). Body mass index and overweight/obesity were positively related to intima-media thickness (r = 0.259; p = 0.012 and r _s = 0.230; p = 0.027, respectively), whereas family history of cardiovascular disease was unrelated. Only gender and overweight/obesity were related to intima-media thickness in a multiple linear regression model (R ² = 0.125; p = 0.002). Male gender and overweight/obesity were associated with increased intima-media thickness, whereas family history of cardiovascular disease was unrelated.     

Cross-sectional analysis of cardiovascular risk factors in children with parental history of premature ischemic heart disease

This study aimed to evaluate the presence of cardiovascular risk factors in children with a parental history of premature ischemic heart disease (two- or three-vessel disease diagnosed before the age of 55 in men and 65 in women). A prospective cross-sectional study was performed on 55 children. The following parameters were assessed: body mass index (BMI), waist and hip circumference, blood pressure, lipids profile, fasting glucose (FG), C-reactive protein (CRP), and carotid intimal-medial thickness (CIMT). Twenty-eight children had hypercholesterolemia, and 11 had other forms of dyslipidemia. Sixteen children had a high BMI; 17 had increased CRP levels; 2 were hypertensive; and 2 had impaired FG. CIMT levels were not correlated with age (Pearson r = −0.486; p = 0.78) and height (Pearson r = −6.31; p = 0.84), but they were correlated with cholesterol levels (Spearman r = 0.375; p < 0.005). Most patients (83%) had ≥2 risk factors; half of them had ≥3 risk factors. We concluded that these at-risk children should be carefully screened for all known risk factors.     

Serum Level of Soluble Intercellular Adhesion Molecule-1 Correlates with Pulmonary Arterial Pressure in Children with Congenital Heart Disease

Background  Endothelial activation and vascular inflammation are thought to be the mechanisms of pulmonary hypertension. Increased expression of the intercellular adhesion molecule (ICAM-1) and raised serum level of its soluble form (sICAM-1) are found in various conditions associated with endothelial activation. Methods  Serum samples from 31 children (14 boys and 17 girls; age, 4.9 ± 4.6 years) with congenital heart disease (CHD) collected at the time of cardiac catheterization were analyzed for sICAM-1 level. Uni- and multivariable stepwise linear regression analyses were performed for the following variables against the sICAM-1 level: age, hemoglobin, serum creatinine, systemic arterial pressure (SAP), pulmonary arterial pressure (PAP), pulmonary blood flow (Qp) and resistance (Rp), systemic blood flow (Qs) and resistance (Rs), Qp/Qs, Rp/Rs, and pulmonary and systemic oxygen saturation. Results   The sICAM-1 levels in children who had CHD with and without pulmonary hypertension were 411 ± 110 and 344 ± 81 ng/ml, respectively (p = 0.11). In the univariable models, age, serum creatinine, systolic PAP, mean PAP, diastolic PAP, Rp, and Rp/Rs were significantly correlated with sICAM-1 level. In the multiple stepwise regression model, only mean PAP remained as an independent predictor of sICAM-1 level (r = 0.55; p = 0.002). Conclusion  Children with CHD and pulmonary hypertension had a trend toward elevated sICAM-1 compared with CHD children who had no pulmonary hypertension. A linear correlation was found between mean pulmonary arterial pressure and sICAM-1 level.     

Comparison of blood gas values in arterial and venous blood

Objective : To compare pH and PCO₂ values of simultaneously obtained arterial, arterialized capillary, and venous blood samples and also to compare oxygen saturation (ASaO₂) measured in arterial blood and oxygen saturation by pulse oximetry (PSaO₂).Methods: Prospective study was done in the children admitted in the Pediatric Intensive Care Unit of Christian Medical College Hospital Vellore, requiring critical care. All the three blood gas samples (arterial, capillary and venous) were taken simultaneously and analyzed. Oxygen saturation by pulse oximetry was also recorded.Results: 50 children aged 14 days to 12 years were included in the study. Arterial and capillary pH values were highly correlated (r²=0.9024, p < 0.0001). Out of 16 children with arterial acidosis 9(56%) were identified by capillary blood gas. Arterial and venous pH values also showed good correlation (r²=0.8449, p eric 0.0001). The PCO₂ values of arterial and capillary blood gases were found to be highly correlated (r²=0.9534, p < 0.0001). The capillary blood gas accurately reflected the arterial PCO₂ in 41 (82%) patients. Arterial and venous blood gas PCO₂ values had less correlation (r²=0.5917, p=0.011). The arterial oxygen saturation (ASaO₂) and oxygen saturation by pulse oximetry (PSaO₂) were correlated moderately (r²=0.7241, p eric 0.0001).Conclusion: Even though arterial blood gas analysis is the gold standard, and when an arterial blood gas sample cannot be obtained, a combination of arterialized capillary blood gas and pulse oximetry can be effectively used in acutely ill children of all ages. Venous samples have a good correlation with arterial samples for pH but are not useful for monitoring blood gas status in acutely ill children.     

Does Treatment of Patent Ductus Arteriosus With Cyclooxygenase Inhibitors Affect Neonatal Regional Tissue Oxygenation?

The effect of patent ductus arteriosus (PDA) treatment with cyclooxygenase (COX) inhibitors (indomethacin [INDO] and ibuprofen [IBU]) on regional oxygenation requires further clarification. The authors hypothesized that both INDO and IBU reduce regional tissue oxygenation in preterm neonates with PDA but that the risk is not uniform for different tissues and other factors may contribute. Regional cerebral (rSO_2-C), renal (rSO_2-R), and mesenteric (rSO_2-M) tissue oxygenation measured by near-infrared spectroscopy and peripheral arterial oxygen saturation measured by pulse oximetry were recorded simultaneously before, during, and after treatment with the first dose of INDO or IBU in very preterm-born infants with PDA. Tissue-specific fractional oxygen extraction (FOE) was calculated using the rSO_2-C, rSO_2-R, rSO_2-M, and corresponding SpO₂ measurements. The findings showed a significant reduction in rSO_2-C, rSO_2-R, and rSO_2-M and an increase in regional FOE after treatment with COX inhibitors in approximately one third of the 38 enrolled infants, which were associated with increased baseline regional tissue oxygen saturation (p?<?0.01). However, the infants with posttreatment reduction of tissue oxygenation had significantly lower baseline rSO_2-C (66.7?±?8.1 vs 69.7?±?8.1?%), rSO_2-R (55.2?±?10.8 vs 62.7?±?11.8?%) and especially rSO_2-M (37.8?±?11.4 vs 46.7?±?16.0?%) than the neonates with unchanged or increased tissue oxygenation. The two groups did not differ in terms of the risk for posttreatment reduction in regional tissue oxygenation with respect to either INDO or IBU treatment and their respective blood levels. Treatment of PDA with either INDO or IBU is associated with a 30?C40?% risk for a reduction in regional tissue oxygenation, which is more pronounced in mesenteric tissue than in cerebral or renal tissue. Despite the inconsistency, reduction of regional tissue oxygenation in preterm infants with PDA is more likely associated with the administration of INDO than with the administration of IBU.     

Chronic night cough and asthma severity in children with stable asthma

The relationship between night cough and other indices of asthma severity was studied in 21 children with clinically stable asthma and persistent night cough. Overnight cough was quantified and related to symptom scores, oxygen saturation (S_aO₂) during sleep, evening and morning peak flow recordings and daytime tests of lung function. In the index group the median number of coughing episodes was 23 (range 1–158). Only 4 children had counts of <10 overnight, similar to the comparison group of 12 children all of whom had counts of <10. There was a trend towards the association of overnight cough with reduced evening peak flow (r=–0.407,P=0.07) and reduced S_aO₂ (r=–0.36,P=0.10). Abnormalities in daytime tests of lung function were observed in 13 children. There was no relationship between night cough and daytime indices of lung function abnormality although children with more severe daytime abnormalities also had significant night cough. Conversely, five children with chronic night cough had normal daytime function.Conclusion Night-time cough in children with asthma is not simply a reflection of daytime lung function status, whereas, overnight S_aO₂ correlates well. Other factors need to be explored to explain the variability of night-time cough in these children.