NIRS Hemodynamic Response to Methylphenidate in Children with Attention Aeficit Hyperactivity Disorder: First Administration, Titration Phase and Associations with Clinical Severity

Introduction

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by lack of self-regulation and deficits in organizing behaviors in response to emotional stimuli. Methylphenidate (MPH) is one of the most effective psychostimulant drugs for ADHD, however, a possible predictive utility of brain hemodynamic data related to MPH administration and its relation to clinical symptomatology is still not clear. To address these questions, we used Near Infrared Spectroscopy (NIRS) technology, a non-invasive optical technique that allows to investigate the effect of psychopharmacological treatment on cortical hemodynamics.

Methods

Twenty children with ADHD underwent a three-waves study and 25 healthy controls were recruited at W1. At W2 children with ADHD received first MPH administration and at W3 they reached the titration phase. At each phase children performed - during NIRS recording - an emotional continuous performance task with visual stimuli of different emotional content. Clinical data were also collected at W1 and W3. We investigated the relationship among the difference between NIRS activation at W2 and W1 (Delta1) and W3 and W2 (Delta2), for each subject, task condition and brain region. Lastly, we investigated correlations between the Delta1 and clinical symptomatology indexes at W1 and between Delta2 and clinical data at W3.

Conclusions

Our study results suggest that hemodynamic changes in right prefrontal region probably induced by first MPH administration could predict hemodynamic changes related to MPH titration phase. These biological indexes could be associated to clinical evidences related not only to core ADHD symptoms but also to affective correlates.

Disclosure

No significant relationships.

Safety and reliability of dobutamine stress echocardiography in pediatric and young adult patients with coronary arteries abnormalities

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study was conducted with the support of Regione Marche, Italy

Background

Risk stratification in coronary arteries abnormalities (CAA), both anomalous aortic origin of a coronary artery (AAOCA) and myocardial bridges (MBs), is still challenging. A reliable method to detect myocardial ischemia is missing in these anomalies. We studied the safety and feasibility of dobutamine stress echocardiography (DSE), compared with exercise stress echocardiography (ESE), in pediatric and young adult patients with CAA.

Methods

In 2019-21, N = 27 CAA [median age 16 years (Q1–Q3: 11, 22)] (n= 23 AAOCA, n = 4 MBs) were assessed. ESE was performed 1-2 days before the DSE examination, double-blinded for examiners and patients. Hemodynamic response and major (cardiac arrest, myocardial infarction, ventricular arrhythmia) and minor [hypertension (≥ 200/120 mmHg), paradoxical bradycardia, chest pain, nausea/vomiting, skin rash, anxiety, dizziness, dyspnea] events were recorded. Differences between rest/stress and DSE/ESE for wall motion abnormalities (WMA) and global longitudinal strain (GLS) were evaluated. Inter-observer agreement was also tested using the kappa (k) coefficient.

Results

Heart rate and blood pressure increased significantly from baseline (p < 0.001) in both DSE and ESE exams. Only DSE tests reached a heart rate ≥ 150 bpm (p < 0.001), while younger patients barely reached the heart rate target and frequently showed less compliance to the test. No patient had major events, while 5 (18.5%) had minor events, the majority during DSE. Inducible WMA were observed only at DSE examinations. Inter-observer agreement for WMA and GLS changes was good for both examinations (95%, k = 0.85, p < 0.001).

Conclusions

DSE is feasible in pediatric and young adult patients with AAOCA and MBs to assess inducible WMA and GLS rest/stress changes. It can be performed safely with a low incidence of major/minor events, with a better performance when compared to ESE. DSE is potentially a valuable test for detecting myocardial ischemia and probably helpful in managing CAA patients.

Third-generation laser balloon ablation for atrial fibrillation treatment: a multicenter experience

Background

Laser balloon ablation is a promising option for performing pulmonary vein isolation (PVI) which is the cornerstone of invasive atrial fibrillation (AF) treatment.

Purpose

We aimed to investigate the acute efficacy and safety of the novel third-generation of the laser balloon system in an initial multicenter experience.

Methods

First and consecutive patients who underwent PVI with LB3 for drug-resistant paroxysmal or persistent AF at 7 Italian sites were included in this analysis. Study endpoints were acute procedural efficacy, defined as successful isolation of all identified PVs without radiofrequency touch-up, total and fluoroscopy times, and periprocedural complications.

Results

Our population included 86 patients (81% males, mean age 60.6±9.5 years) who underwent a procedure of PVI using LB3 between June 2020 and March 2021.

Most patients had paroxysmal AF (74%) and were in sinus rhythm at the beginning of the procedure. The mean procedure time was 138±60 min; fluoroscopy time was 22±17 min and the mean ablation time was 44±40 min. Of the 313 targeted PVs, 311 (99.4%) could be isolated with first-pass LB3 application, while 2 (0.6%) required radiofrequency touchup. At the end of the procedure, all patients were in sinus rhythm and 26 (32%) received electrical cardioversion to achieve stable sinus rhythm.

The total rate of major compilations was 1.2% (1/82 patients): one pericardial tamponade requiring epicardial puncture. No surgical intervention was necessary, and the patient recovered without any sequalae. There were no vascular access complications or phrenic nervy palsy. Three pinhole balloon raptures (3.5%) were observed during energy applications that required replacement of the whole system but had no effect on patient safety.

Conclusions

In a first multicenter experience, the LB3 system for PVI was safe with excellent acute efficacy.

Funding Acknowledgement

Type of funding sources: None.

The predictive role of neutrophil-to-lymphocyte ratio in post-operative arrhythmias in pediatric patients after cardiopulmonary bypass surgery

Background

Postoperative arrhythmias (POA) are a common complication after cardiac surgical repairs for congenital heart disease (CHD), representing a substantial source of morbidity, mortality and prolonged total in-hospital stay, with an incidence of 7.5–48% in postoperative pediatric cardiac patients. The etiology is multifactorial, and it has been related to the direct surgical manipulation of the cardiac conduction system, to the local tissue inflammation in the myocardium adjacent to the conduction system and to the arrhythmogenic effects of cardiopulmonary bypass (CPB), inotropes and electrolyte disturbances. Recently, the prognostic role of neutrophil-to-lymphocyte ratio (NLR), a novel inflammation marker, has been evaluated in pediatric patients after CPB surgery.

Purpose

To evaluate the predictive role of NLR in POA in a population of pediatric CHD patients after CPB.

Methods

We retrospectively collected perioperative clinical and laboratory data of 146 patients (age 8.27±10.79 years; male gender: 60.8%) consecutively admitted to the cardiac surgery intensive care unit (ICU) of our institute after elective cardiac surgery with CPB in 2018. We grouped and analyzed our population over NLR tertiles evaluated at 24 hours from CPB and types of POA: supraventricular (SVT) and junctional (JET). The prognostic value of NLR and its association with POA was analyzed.

Results

Diagnoses of 146 patients included atrial septal defect (n=36), ventricular septal defect (n=20), pulmonary atresia/stenosis (n=10), tetralogy of Fallot (n=20), endocardial cushion defect (n=8), left ventricular outflow tract obstruction (n=14), anomalous origin of coronary artery (n=6), complex CHD (n=13), interrupted/hypoplastic aortic arch (n=12), anomalous pulmonary artery venous return (n=3). The mean CPB time was 121.6±84.6 minutes. The median ICU hospitalization was 48 hours [Q1, Q3: 24, 96]. Twelve patients experienced POA: 6 SVT and 6 JET. The frequency of POA incremented over NLR-tertiles (P-Trend 0.017), while SVT onset was associated with higher values of NLR and C-reactive protein (P=0.034 and P=0.011, respectively). Patients in the second and third tertiles of NLR had a prolonged hospitalization (Log-rank, P=0.029), especially when associated with POA (Log-rank, P=0.012). At the multivariable analysis, higher age and NLR values were independently associated with SVT [OR per year 1.22; 95% CI (1.02, 1.25), P=0.043 and OR per point 1.91; 95% CI (1.29, 2.82), P=0.012, respectively], but not with JET.

Conclusions

24-h post-CPB NLR can predict postoperative SVT in a population of pediatric CHD patients. Our data suggest that the NLR could be a useful, easy-to-obtain marker for postoperative outcome in pediatric patients who had undergone elective CPB.

Funding Acknowledgement

Type of funding sources: None.

Psychological and Structural Barriers to Immigrant Community Participation: The Experience of Peruvians in Santiago de Chile

Community participation can be considered a pillar for the promotion of social justice and well-being for immigrants in new countries. Participation may be influenced by different forms of oppression which decrease opportunities for immigrants to be engaged. The present study explores the difficulties that Peruvian immigrants encountered and still encountering to participate in Santiago de Chile through in-depth qualitative interviews. Eighteen semi-structured interviews were conducted with Peruvian leaders of Ethnic Community Based Organizations (ECBOs) in Santiago de Chile. Interviews focused on the community engagement of Peruvians highlighting the difficulties they encountered when deciding whether to engage and throughout the process of carrying out their commitment, along with their perceptions when trying to engage their compatriots. The present study contributes to the literature in three aspects. First, it focused on the phenomenon of South-South migration. Secondly, it delved into the psychological and structural barriers that immigrants' experience, considering their disadvantaged conditions. Thirdly, it used Situational Analysis, along with the constructionist drift of Grounded Theory, which is widely used in critical, qualitative research, and is sensitive to producing situated knowledge. Coding and mapping analysis identified experiences related to historical trauma, transnational bonds, and dominant master narratives in both countries as well as challenges due to balancing time and priorities, surviving institutional deterrents, and inter-organizations competitiveness. Finally, transnational commitments, mechanisms of social disconnection, and under valuated rights that Peruvians may live in Chile were pointed out. These results intend to have practical implications for immigrants and for community psychologists.

Ross procedure and aortic valve repair: long-term echocardiographic outcomes, quality of life and physical activity of different aortic valve surgery procedures

Funding Acknowledgements

Type of funding sources: None.

Background

 To compare long-term outcomes of aortic valve repair (AVr) and pulmonary autograft replacement (Ross procedure) in terms of echocardiographic parameters, quality of life (QoL), physical activity (PA).

Methods

 In 2005-19, 129 patients (median age 22 [13, 33 IQR], 75% males) underwent aortic surgery in our Department: 40 were Ross (22 years [19, 51 IQR]), 67 AVr (17 years [1, 50 IQR]) and 22 aortic valve replacements (52 years [30, 80 IQR]). We focused on Ross and AVr. Retrospectively, relevant data were collected from medical records and phone re-calls. Physical activity (spontaneous and active) and QoL were assessed utilizing the IPAQ and SF-36 questionnaires. All patients underwent echocardiography pre/post-surgery and the follow-up lasted 12 ± 4 years.

Results

 At the baseline, Ross patients had more aortic stenosis than insufficiency (P = 0.045). At the follow-up, Ross procedures presented more right-ventricle and aortic annulus dilatation (P = 0.002 and P = 0.030, respectively), but higher left-ventricular global longitudinal strain (LV GLS: 18 ± 3.2 % vs. 16 ± 3.3, P = 0.0027). Conversely, AVr experienced more re-do operations (Log-rank P = 0.005). Ross reported better QoL (SF-36: 0.8 ± 0.07 vs. 19 ± 0.4, P-0.045) and were also more active in daily PA (IPAQ ≥ 2500 Mets: 63.8% vs. 6%; P = 0.006). Ross patients practiced more sports activities than AVr (P = 0.011).

Conclusions

 In a relatively small cohort of young and adults post aortic surgery patients, Ross procedures had better prognosis in terms of re-do operations; presented better ventricular function, as assessed by LV GLS. Ross patients had better long-term QoL and showed more spontaneous PA and involvement in sports activity.

1163 Diagnostic performance of a new echocardiographic method for coronary arteries abnormalities assessment

Background

The echocardiographic assessment of coronary arteries abnormalities (CCA) has always been challenging. In this view, we aimed to assess the performance of a new echocardiographic-based diagnostic method for CAA in pediatric and young adults’ population.

Methods

over 5 years, we examined all the outpatients undergoing routine echocardiography in our department. Our method consisted of 4-focused specific view scan: parasternal short-axis, parasternal long-axis, both left and right outflow tract, and apical 5-chamber view. Coronary-CT confirmed the CAA diagnosis. Two independent physicians retrospective reviewed the echocardiographic images, in a double-blinded fashion (coronary-CT and diagnosis), for performance analysis.

Results

in 2014-18, 5,998 outpatients underwent echocardiography (median age 14 years [6, 21 - IQR]). A total of 27 CAA were diagnosed: overall prevalence 0.0045%, 0.022% of incidence. N = 17/27 were anomalous aortic origin of coronary arteries (AAOCA), N = 3/27 anomalous coronary arteries from the pulmonary artery (ACAPA), and 7/27 fistulas. After the implementation, we found a progressive increment of CAA diagnosis (P for Trend = 0.038), in particular of AAOCA: both left and right coronaries (P-trend = 0.021 and P = trend 0.010, respectively). Our method showed better sensitivity than traditional CAA echocardiographic evaluation: 85% vs 55%, P = 0.032 [AUC 0.77, 95% CI (0.68, 0.87) and AUC 0.92, 95% CI (0.85, 0.99), respectively], with a good interobserver agreement for the adjudicated double-blinded retrospective diagnosis (99.75%, K = 0.73, P < 0.001).

Conclusions

the application of a new echocardiographic-based method for CAA-detection led to a significantly increased rate of identified anomalies. This approach demonstrated better sensitivity than traditional echocardiographic assessment. Implementing this protocol in clinical practice may improve the CAA diagnosis, and probably reduce the occurrence of CAA-related sudden cardiac death.

Immunosuppressive Acidic Protein (Iap) and Ca 125 Assays in Detection of Human Ovarian Cancer: Preliminary Results

Serum levels of the immunosuppressive acidic protein (IAP) and CA-125 were measured in 45 patients with ovarian tumors (30 malignant and 15 benign) before surgery. Concentrations of both markers were slightly increased in benign forms but still within the upper limit for controls.

The sensitivity of IAP in detecting ovarian cancer was higher than CA-125 (83.4% versus 76.7%). Five false negatives were observed in IAP assay and seven for CA-125. Parallel determination of both markers, however, improved the diagnostic accuracy up to 90.0% of the total malignant cases. Combined measurements of circulating IAP and CA-125 are therefore recommended in the detection of ovarian cancers.

Imaging Work-Up for Peritoneal Access Care and Peritoneal Dialysis Complications

Peritoneal dialysis (PD) represents a treatment opportunity for patients with end-stage renal failure, but it has particular complications that sometimes force cessation of this procedure (1–9). These complications are due to the presence of the peritoneal catheter and of dialysis solution within the peritoneal cavity. Infections are the most common complications of PD, followed by mechanical complications.

Diagnostic imaging of the complications of PD is important because such an evaluation can aid in the diagnosis and in the decision making process about the treatment. In this review we present the main radiologic investigations employed: plain radiograph, US, peritoneography, computed tomography peritoneography, magnetic resonance peritoneography, peritoneal scintigraphy.

To diagnose catheter-related problems plain radiograph, ultrasonography and peritoneography can be useful. US is useful in diagnosing and following-up exit-site and tunnel infections. Peritoneography and C T-peritoneography, alone or in combination, can be recommended as gold standard investigation to assess mechanical peritoneal dialysis complications, such as catheter malfunction, leaks, hernias and sclerosing peritonitis. Newer methods, such as MR peritoneography or scintigraphy could be useful in selected patients, on center-based experience. An appropriate use of radiology may significantly improve technique survival, morbidity and mortality of patients treated with PD.

The predictive value of ABCB1, ABCG2, CYP3A4/5 and CYP2D6 polymorphisms for risperidone and aripiprazole plasma concentrations and the occurrence of adverse drug reactions

We investigated in ninety Caucasian pediatric patients the impact of the main polymorphisms occurring in CYP3A, CYP2D6, ABCB1 and ABCG2 genes on second-generation antipsychotics plasma concentrations, and their association with the occurrence of adverse drug reactions. Patients with the CA/AA ABCG2 genotype had a statistically significant lower risperidone plasma concentration/dose ratio (Ct/ds) (P-value: 0.007) and an higher estimated marginal probability of developing metabolism and nutrition disorders as compared to the ABCG2 c.421 non-CA/AA genotypes (P-value: 0.008). Multivariate analysis revealed that the ABCG2 c.421 CA/AA genotype was found associated to a higher hazard (P-value: 0.004) of developing adverse drug reactions classified as metabolism and nutrition disorders. The ABCB1 2677TT/3435TT genotype had a statistically significant lower aripiprazole Ct/ds if compared with patients with others ABCB1 genotypes (P-value: 0.026). Information obtained on ABCB1 and ABCG2 gene variants may result useful to tailor treatments with these drugs in Caucasian pediatric patients.

A case of dysgraphia induced by sertraline and a review of official spontaneous adverse reaction databases

WHAT IS KNOWN AND OBJECTIVES

The occurrence of dysgraphia after sertraline intake has never been reported. The objective was to describe a case of this adverse drug reaction and present a review of similar cases held in international databases with a discussion of the possible pharmacological mechanisms.

CASE SUMMARY

We observed a 60-year-old man who experienced resting tremors, dyskinesia and dysgraphia 2 months after a stepwise increase in sertraline dosing from 50 to 200 mg/day.

WHAT IS NEW AND CONCLUSION

Dysgraphia is a possible adverse drug reaction to sertraline, and we suggest that inhibition of extrapyramidal dopaminergic activity might be the pharmacological mechanism.

Esophageal pressure measurements under different conditions of intrathoracic pressure. An in vitro study of second generation balloon catheters

BACKGROUND

The aim of this study was to evaluate in vitro the accuracy of second generation esophageal catheters at different surrounding pressures and filling volumes and to suggest appropriate catheter management in clinical practice.

METHODS

Six different esophageal catheters were placed in an experimental chamber at four chamber pressures (0, 10, 20 and 30 cmH2O) and at filling volumes ranging from 0 to 10 mL. The working volume was defined as the volume range between the maximum (Vmax) and minimum (Vmin) volumes achieving acceptable accuracy (defined by a balloon transmural pressure ± 1 cmH2O). Accuracy was evaluated for a standard volume of 0.5 mL and for volumes recommended by manufacturers. Data are shown as median and interquartile range.

RESULTS

In the four conditions of chamber pressure Vmin, Vmax and working volume were 1.0 (0.5, 1.5), 5.3 (3.8, 7.1), and 3.5 (2.9, 6.1) mL. Increasing chamber pressure increased Vmin (rho=0.9; P<0.0001), that reached 2.0 mL (1.6-2.0) at 30 cmH2O. Vmax and working volumes differed among catheters, whereas Vmin did not. By injecting 0.5 mL and the minimum recommended volume by manufacturer, balloon transmural pressure was <-1 cmH2O in 71% and 53% of cases, it was negatively related to chamber pressure (rho=-0.97 and -0.71; P<0.0001) and reached values of -10.4 (-12.4, -9.7) and -9.8 (-10.6, -3.4) at 30 cmH2O.

CONCLUSION

Measuring positive esophageal pressures needs higher injected volumes than usually recommended. The range of appropriate filling volumes is catheter-specific. Both absolute values and respiratory changes of esophageal pressure can be underestimated by an underfilled balloon.

Bridge to transplantation using paracorporeal biventricular assist devices or the syncardia temporary total artificial heart: is there a difference?

AIM

Biventricular support can be achieved using paracorporeal ventricular assist devices (p-BiVAD) or the Syncardia temporary total artificial heart (t-TAH). The purpose of the present study was to compare survival and morbidity between these devices.

METHODS

Data from 2 French neighboring hospitals were reviewed. Between 1996 and 2009, 148 patients (67 p-BiVADs and 81 t-TAH) underwent primary, planned biventricular support. There were 128 (86%) males aged 44±13 years.

RESULTS

Preoperatively, p-BiVAD recipients had significantly lower systolic and diastolic blood pressures, more severe hepatic cytolysis and higher white blood cell counts than t-TAH recipients. In contrast, t-TAH patients had significantly higher rates of pre-implant ECLS and hemofiltration. Mean support duration was 79±100 days for the p-BiVAD group and 71±92 for t-TAH group (P=0.6). Forty two (63%) p-BiVAD recipients were bridged to transplantation (39, 58%) or recovery (3, 5%), whereas 51 (63%) patients underwent transplantation in the t-TAH group. Death on support was similar between groups (p-BiVAD, 26 (39%); t-TAH, 30 (37%); P=0.87). Survival while on device was not significantly different between patient groups and multivariate analysis showed that only preimplant diastolic blood pressure and alanine amino-transferase levels were significant predictors of death. Post-transplant survival in the p-BiVAD group was 76±7%, 70±8%, and 58±9% at 1, 3, and 5 years after transplantation, respectively, and was similar to that of the t-TAH group (77±6%, 72±6%, and 70±7%, P=0.60).

CONCLUSION

Survival while on support and up to 5 years after heart transplantation was not significantly different in patients supported by p-BiVADs or t-TAH. Multivariate analysis revealed that survival while on transplantation was not affected by the type of device implanted.

Throbbing headache associated with enoxaparin administration: a case report, a review of pharmacovigilance databases for similar cases and possible mechanisms

WHAT IS KNOWN AND OBJECTIVES

To date, no case of headache has been reported with enoxaparin. We present the case of a 60-years-old man, who developed enoxaparin-induced throbbing headache and discuss the possible pharmacological mechanisms. We provide an analysis of enoxaparin-induced headache in three international databases.

CASE SUMMARY

A few hours after the subcutaneous administration of this drug at therapeutic dose, the patient experienced throbbing headache. Rechallenge on two other separate occasions separated by several days produced the same effect although with reduced intensity when the dose was lowered. The Naranjo Algorithm indicated a 'certain' relationship.

WHAT IS NEW AND CONCLUSION

We report a case of throbbing headache associated with the use of enoxaparin; with the increasing use of enoxaparin, physicians who prescribe this drug should be aware of this potential ADR. We suggest that it is a heparin class-effect, and therefore, a more general caution is also appropriate.

The first steps towards the era of personalised vaccinology: predicting adverse reactions

Until now, the occurrence of adverse reactions among individuals inoculated with identical vaccines has been ascribed to unpredictable stochastic processes. Recent advances in pharmacogenomics indicate that some features of host response to immunisation are influenced by genetic traits, henceforth predictable. The ability to predict the adverse reaction to vaccination would represent an important step towards the development of personalised vaccinology and could enhance public confidence in the safety of vaccines. Herein, we have reviewed all the available information on the association between genetic variants and the risk for healthy subjects to develop adverse reactions.

Pharyngeal spasticity due to dantrolene

WHAT IS KNOWN AND OBJECTIVE

Dantrolene can be combined with baclofen to better treat spasticity, but may cause muscular weakness and dysphagia. We instead describe a pharyngeal spasm due to dantrolene.

CASE SUMMARY

A 12-year-old male received dantrolene 3 mg/kg/day in adjunct to baclofen 2 mg/kg/day, to improve spasticity. After 5 days of full-dose dantrolene, his dysphagia worsened and he developed pharyngeal spasm. Dantrolene was suspected for an adverse reaction and removed. The patient subsequently improved.

WHAT IS NEW AND CONCLUSION

Causality analysis determined a probable relationship between dantrolene and pharyngeal spasm. This may be due to direct muscle contraction by dantrolene, an effect seen previously in vitro.

Neurological and psychiatric adverse events with prucalopride: case report and possible mechanisms

WHAT IS KNOWN AND OBJECTIVE

Chronic constipation is very frequent in the general population. Although usually considered banal, this disorder has considerable personal, social and healthcare impact. Several studies have shown that the psychological impact exceeds that caused by rheumatoid arthritis or haemodialysis. Recently, prucalopride, a highly selective 5-HT4 receptor agonist has been shown to improve the symptoms of chronic constipation and to have a beneficial effect on social and healthcare impact. The drug was approved by the European Medicine Agency, in 2009 at a dose of 2 mg/day, 'for symptomatic treatment of chronic constipation in women in whom laxatives fail to provide adequate relief'. Neurological side effects or psychiatric disorders have not been reported previously with prucalopride. We present the case of a 61-year-old woman, who developed such adverse effects when given prucalopride for the treatment for chronic constipation.

CASE SUMMARY

A few hours after oral administration of this drug at therapeutic dose (2 mg/day), the patient experienced life-threatening neurological effects that included visual hallucination, loss of balance and memory, disorientation, exhaustion and suicidal ideation. Analysis with the Naranjo algorithm indicated a 'possible' relationship between prucalopride and these disorders.

WHAT IS NEW AND CONCLUSION

This is the first report of prucalopride-induced neurological side effects and psychiatric disorders with prucalopride. The absence of other similar reports suggests that prucalopride rarely causes these adverse effects.

Effect of the adjunct of carbon dioxide during cardiopulmonary bypass on cerebral oxygenation

INTRODUCTION

Over the last few years, near-infrared spectroscopy (NIRS) has been introduced to study cerebral haemodynamics and oxygenation. This paper points out how the use of an external source of CO2 effects on the absolute value of cerebral NIRS during cardiac surgery on cardiopulmonary bypass.

PATIENTS AND METHODS

Between January 2010 and September 2011, 368 patients underwent congenital heart disease correction on cardiopulmonary bypass (CPB). Nineteen patients, with a mean age of 26 days (range 6-120 days), required an external source of CO2 to correct hypocarbia during cardiopulmonary bypass. Different parameters were monitored: NIRS value, oxygen saturation, oxygen partial pressure, CO2 partial pressure, haematocrit, mean arterial pressure and pH. They were analyzed during different phases of the surgical procedure: before, during and after CO2 infusion.

RESULTS

There were no deaths during the hospital stay. The NIRS value increased significantly (p<0.05) after the addition of CO2, from a starting value of 52.9 to a final value of 63.4. PaCO2 was found to increase too: from 31.3 mmHg to 40.6 mmHg. On the other hand, both values decreased when the CO2 was removed, to respective final values of 55.8 and 34.4 mmHg. Mean arterial pressure, haematocrit and PaO2 didn't modify significantly during this period.

CONCLUSIONS

Nowadays, NIRS is usually used in cardiac surgery to reduce possible risks of neurological damage. The importance of the role of pCO2 in the cerebral vascular resistance and in cerebral blood flow has already been proven. This research demonstrates a relationship between pCO2 and the NIRS value. This paper could introduce an important correcting tool when an inadequate NIRS value occurs although the level of oxygenation, haematocrit and mean arterial pressure are acceptable and the arterial line is accurately positioned.

Non-invasive cerebral oximetry monitoring during cardiopulmonary bypass in congenital cardiac surgery: a starting point

INTRODUCTION

Non-invasive cerebral monitoring with the INVOS cerebral oximeter is an accepted good indicator of cerebral metabolism. In recent years, it has been used in the monitoring of patients who underwent cardiac surgery. Herein, we describe the INVOS trend during cardiopulmonary bypass (CPB) in a cohort of patients operated in our institution for congenital heart disease.

PATIENTS AND METHODS

Between December 2009 and March 2010, 40 patients (mean age 8.4 years; range 11 days-60 years) underwent cardiac surgical procedures using CPB. Values of INVOS cerebral parameter, pH, oxygen saturation, and CO(2) level were collected pre CPB, during cooling, re-warming and weaning, and post CPB. INVOS parameters were evaluated according to CPB priming, age and preoperative oxygen saturation.

RESULTS

Patients were divided according to CPB priming (haematic vs clear), age (≤1 vs >1 year of age) and oxygen saturation (≤92% vs >92%). During the operations, the trend demonstrated a reduction in INVOS value at the institution of CPB and a further reduction during the cooling phase in all groups.This has been correlated to the loss of pulsatile flow. However, the value recovered during re-warming, weaning and CPB discontinuation. Cyanotic patients presented a lower cerebral oximetry compared to acyanotic patients during the whole CPB period. Between age and priming groups, we noticed a statistical difference in cerebral oximetry, with a lower value in the younger patients and in the haematic priming group. This might be interrelated because all patients younger than 1 year old always received haematic CPB priming.

CONCLUSIONS

We demonstrated that cerebral oximetry decreases with the loss of pulsatile flow regardless of the mean arterial pressure and, furthermore, is not directly related to the haematocrit value in patients with reduced pulmonary blood flow.

The Electrical Resistance Properties of Shape Memory Alloys

Shape memory alloys are known for their ability to build up large deformations under an applied stress, either in martensitic phase or in the pseudoelastic region.

The electrical resistance of shape memory alloys, traditionally used to define the transformation temperatures, shows interesting features when considering its modification as a function of strain. The electrical resistance in NiTiCu ribbons, obtained by melt spinning, is here examined, either in martensite or in the pseudoelastic range or under a constant applied stress across the transformation range. In each examined case, the results obtained show that the electrical resistance follows a linear relationship as a function of the imprinted strain.

Effects of prostaglandin E1alpha cyclodextrin [corrected] treatment on endothelial dysfunction in patients with systemic sclerosis

OBJECTIVE

Systemic sclerosis (SSc) is characterized by an altered nitric oxide (NO): endothelin I ratio and by endothelial dysfunction.

AIMS

To verify the effects of prostaglandin E1 (PGE1) alpha-cyclodestrin treatment on endothelial function, quantified as flow-mediated dilation (FMD) of the radial artery.

METHODS

In 16 women with SSc (age 57 +/- 2.7 years, means +/- SE) in whom a diagnosis of SSc had been made several years earlier (7.1 +/- 1.2 years), FMD was evaluated by an echotracking technique on the radial artery, using trinitroglycerin vasodilation as a non-endothelial measure of the vessel's ability to increase its diameter maximally. FMD was evaluated after 4 months washout period and after 4 months cyclic infusion of PGE1 alpha-cyclodestrin. Expired NO was measured at the same time.

RESULTS

PGE1 alpha-cyclodestrin cyclic infusions did not modify systolic and diastolic blood pressure, heart rate or trinitroglycerin radial artery vasodilation. On the other hand, it induced a marked and significant increase in FMD of the radial artery, which was also accompanied by an increase in blood flow and expired NO.

CONCLUSIONS

Endothelial dysfunction and reduced FMD associated with SSc are improved by cyclic treatment with PGE1 alpha-cyclodestrin. This effect occurs together with a concomitant increase in expired NO, suggesting its direct positive influence on endothelial function. It may also partly explain the clinical beneficial effect of the drug in SSc.