Vincenzo Vitale

Fenoldopam in newborn patients undergoing cardiopulmonary bypass: controlled clinical trial

We determined if low dose fenoldopam in neonates already receiving conventional diuretics improves urine output, fluid balance, acute kidney injury incidence (AKI) and time to extubation. A prospective controlled clinical trial in a pediatric cardiac intensive care unit on 40 neonates undergoing cardiac surgery with cardiopulmonary bypass, excluding simple ventricular septal defect and atrial septal defect. Fenoldopam was infused at a low dose of 0.1 microg/kg/min soon after anesthesia induction and infusion prolonged for 72 h in 20 patients. Twenty neonates with standardized perioperative therapy except fenoldopam administration served as controls. Demographic, hemodynamic, daily urine output, creatinine, creatinine clearance, serum and urinary sodium and potassium were recorded. Inotropic score (IS) was calculated as a surrogate for the degree of hemodynamic impairment. Low dose fenoldopam infusion did not show beneficial effects in renal function. The treatment did not significantly affect IS value, AKI incidence, fluid balance control, time to sternal closure, time to extubation and time to intensive care unit discharge. Low dose fenoldopam in neonates undergoing cardiac surgery with CPB did not produce effects on urine output, fluid balance and AKI incidence. Fenoldopam was well tolerated and did not negatively affect hemodynamics and vasopressor support.

Renal replacement therapy in neonates with congenital heart disease.

BACKGROUND The acute renal failure (ARF) incidence in pediatric cardiac surgery intensive care unit (ICU) ranges from 5 to 20% of patients. In particular, clinical features of neonatal ARF are mostly represented by fluid retention, anasarca and only slight creatinine increase; this is the reason why medical strategies to prevent and manage ARF have limited efficacy and early optimization of renal replacement therapy (RRT) plays a key role in the outcome of cardiopathic patients. METHODS Data on neonates admitted to our ICU were prospectively collected over a 6-month period and analysis of patients with ARF analyzed. Indications for RRT were oligoanuria (urine output less than 0.5 ml/kg/h for more than 4 h) and/or a need for additional ultrafiltration in edematous patients despite aggressive diuretic therapy. RESULTS Incidence of ARF and need for RRT were equivalent and occurred in 10% of admitted neonates. Eleven patients of 12 were treated by peritoneal dialysis (PD) as only RRT strategy. PD allowed ultrafiltration to range between 5 and 20 ml/h with a negative balance of up to 200 ml over 24 h. Creatinine clearance achieved by PD ranged from 2 to 10 ml/min/1.73 m2. We reported a 16% mortality in RRT patients. CONCLUSION PD is a safe and adequate strategy to support ARF in neonates with congenital heart disease. Fluid balance control is easily optimized by this therapy whereas solute control reaches acceptable levels.

Comparative evaluation of high-flow nasal cannula and conventional oxygen therapy in paediatric cardiac surgical patients: a randomized controlled trial

OBJECTIVES The aim of this study was to compare high-flow nasal cannula (HFNC) and conventional O2 therapy (OT) in paediatric cardiac surgical patients; the primary objective of the study was to evaluate whether HFNC was able to improve PaCO2 elimination in the first 48 h after extubation postoperatively. METHODS We conducted a randomized, controlled trial in pediatric cardiac surgical patients under 18 months of age. At the beginning of the weaning of ventilation, patients were randomly assigned to either of the following groups: OT or HFNC. Arterial blood samples were collected before and after extubation at the following time points: 1, 6, 12, 24 and 48 h. The primary outcome was comparison of arterial PaCO2 postextubation; secondary outcomes were PaO2 and PaO2/fractional inspired oxygen (FiO2) ratio, rate of treatment failure and need of respiratory support, rate of extubation failure, rate of atelectasis, simply to complications and the length of paediatric cardiac intensive care unit stay. RESULTS Demographic and clinical variables were comparable in the two groups. Analysis of variance for repeated measures showed that PaCO2 was not significantly different between the HFNC and OT groups (P = 0.5), whereas PaO2 and PaO2/FiO2 were significantly improved in the HFNC group (P = 0.01 and P = 0.001). The rate of reintubation was not different in the two groups (P = 1.0), whereas the need for noninvasive respiratory support was 15% in the OT group and none in the HFNC group (P = 0.008). CONCLUSIONS HFNC had no impact on PaCO2 values. The use of HFNC appeared to be safe and improved PaO2 in paediatric cardiac surgical patients.

Management of fluid balance in continuous renal replacement therapy: technical evaluation in the pediatric setting.

Fluid overload control and fluid balance management represent very important factors in critically ill children requiring renal replacement therapy A relatively high fluid volume administration in children and neonates is often necessary to deliver adequate amounts of blood derivatives, vasopressors, antibiotics, and parenteral nutrition. Fluid balance errors during pediatric continuous renal replacement therapy (CRRT) might significantly impact therapy delivery and have been described as potentially lethal. The aim of this study was to evaluate the accuracy of delivered vs. prescribed net ultrafiltration (UF) during CRRT applied to 2 neonates and 2 small children, either as dialytic treatment alone or during extracorporeal membrane oxygenation (ECMO). In accordance with an Acute Dialysis Quality Initiative workgroup statement, net UF was defined as the “overall amount of fluid extracted from the patient in a given time”. Mean prescribed net UF was 18.5 ml/h (SD=6.7) during neonatal treatments and 70.3 ml/h (SD=22.5) during CRRT in small children. Daily net UF ranged from 200 mL to about 600 mL in the 2 neonates and from 1,200 to 1800 mL in the 2 children. The percentage error of delivered net UF ranged from −1.6% to 5.8% of the prescribed level. The mean error of the ECMO/CRRT patients was 3.024 ml/h vs. 0.45 m/h for the CRRT patients (p<0.001). The same difference was not evident when the 2 neonates were compared with the 2 small children (without considering the presence of ECMO). CRRT and net UF delivery appeared to be accurate, safe, and effective in this small cohort of high-risk pediatric patients.

Role of vasopressin in the treatment of anaphylactic shock in a child undergoing surgery for congenital heart disease: a case report

IntroductionThe incidence of anaphylactic reactions during anesthesia is between 1:5000 and 1:25000 and it is one of the few causes of mortality directly related to general anesthesia. The most important requirements in the treatment of this clinical condition are early diagnosis and maintenance of vital organ perfusion. Epinephrine administration is generally considered as the first line treatment of anaphylactic reactions. However, recently, new pharmacological approaches have been described in the treatment of different forms of vasoplegic shock.Case presentationWe describe the case of a child who was undergoing surgery for ventricular septal defect, with an anaphylactic reaction to heparin that was refractory to epinephrine infusion and was effectively treated by low dose vasopressin infusion.ConclusionIn case of anaphylactic shock, continuous infusion of low-dose vasopressin might be considered after inadequate response to epinephrine, fluid resuscitation and corticosteroid administration.

Lung ultrasonography and pediatric cardiac surgery: First experience with a new tool for postoperative lung complications

Lung ultrasonography is a diagnostic tool increasingly used in critical care. Few data are available for the pediatric population. We describe our experience with lung ultrasonography for 5 pediatric patients with common post-cardiac surgery lung complications (pleural effusion, pneumothorax, atelectasis, pneumonia). Ultrasonography was useful also for lung recruitment. Such data were confirmed by chest radiographs or by computed tomography, or both. Lung ultrasonography can be considered as a useful, real-time, bedside tool to detect specific lung diseases, reliably implementing radiographic images and potentially decreasing the total number of radiographs in critically ill children with congenital heart diseases.

Initial experience with levosimendan infusion for preoperative management of hypoplastic left heart syndrome.

Hypoplastic left heart syndrome (HLHS) in the neonatal period is characterized by pulmonary overflow coupled with systemic hypoperfusion resulting in myocardial dysfunction, multiorgan failure, and severe metabolic derangement. This condition requires that the patient be stabilized by timely medical management before surgical palliation. The safety and efficacy of levosimendan were evaluated with six neonates affected by HLHS who had clinical signs of impending pulmonary overflow/systemic hypoperfusion, defined as tachypnea ([50 breaths/min), tachycardia (heart rate, [180 beats/min), hepatomegaly, central/toe temperature gradient exceeding 10 C, and lactate levels higher than 2 mmol/l. Levosimendan is a novel inodilator agent belonging to the family of calcium sensitizer agents with documented efficacy in treating adult congestive heart failure [2]. To date, few data exist on its use for pediatric patients [4], and no data exist on its use for HLHS neonates. The institutional review board of our hospital approved the use of levosimendan for such a cohort of patients. If all predefined signs of systemic hypoperfusion remained evident for more than 4 h after initial treatment (intravenous furosemide 1 mg/kg, packed red blood cells transfusions targeting a hematocrit level higher than 45%, children warming up to a toe temperature higher than 30 C), the patients were proactively sedated and intubated. Initial ventilator settings, with an inspired oxygen fraction (FiO2) of 30%, aimed to maintain normocapnia (partial pressure of carbon dioxide in arterial gas (PaCO2), 40– 45 mmHg). A central venous catheter was placed in the superior vena cava (SVC), and levosimendan infusion at 0.1 lg/kg/min was administered as the sole inotropic agent. All patients were receiving prostaglandin E1 infusion at 0.01 lg/kg/min since birth for ductal patency. Data are expressed as mean ± standard deviation. The Mann–Whitney test was used to compare means. A p value less than 0.05 was considered significant. The mean patient age at the time of intubation was 2.2 ± 0.5 days. All the patients received a classic Norwood procedure with a Blalock-Taussig shunt after a mean levosimendan administration time of 22 ± 8 h, from start of infusion to initiation of surgery. Lactate levels decreased from 4.22 ± 2.5 to 2.1 ± 0.4 mmol/l (p \ 0.05). Base excess increased from –1.92 ± 4 to 3.5 ± 3 mmol/l (p \ 0.05). The SVC oxygen saturation/systemic saturation (a-vO2) gradient decreased from 41.4% ± 12% to 29% ± 5% (p \ 0.05). Cerebral near infrared spectroscopy (NIRS) saturation improved from 57.8% ± 15.8% to 69.2% ± 7% (p \ 0.05). Central body temperature remained constant between 36 ± 1.5 C and 36.5 ± 0.5 C, whereas peripheral temperature increased significantly from 25.5 ± 1.4 C to 30.4 ± 0.4 C (p \ 0.05). The pulmonary-to-systemic flow ratio (Qp/Qs) was calculated according to the following formula: SatO2 – SvO2/ 99 –SatO2), where SatO2 and SvO2 are the arterial and SVC oxygen saturations, respectively. The pulmonary vein oxygen saturation was assumed to be 99%. The Qp/Qs decreased from 3.8 ± 1.2 to 2.1 ± 0.34 (p \ 0.05). Heart L. Di Chiara Z. Ricci (&) C. Garisto S. Morelli C. Giorni V. Vitale S. Picardo Division of Pediatric Cardiac Anesthesia/Intensive Care Unit, Department of Pediatric Cardiology and Cardiac Surgery, Bambino Gesù Pediatric Hospital, Piazza S.Onofrio, 00100 Rome, Italy e-mail: z.ricci@libero.it

Neurally adjusted ventilatory assist and lung transplant in a child: A case report.

Objective: To report the successful application of neurally adjusted ventilatory assist to a child with cystic fibrosis who underwent single-lung transplantation. Design: Case report. Setting: Pediatric cardiac intensive care unit. Patient: A 15-yr-old male with cystic fibrosis was admitted to our pediatric cardiac intensive care unit after single-lung transplantation. The child had previously received two bowel resections at the age of 1 yr, right pneumonectomy at the age of 3 yrs, and endoscopic percutaneus gastrostomy at the age of 10 yrs. After transplant, the child failed several attempts of weaning off mechanical ventilation with pressure-support ventilation, due to infection, pneumothorax, and ventilator asynchrony that caused gastric distension and numerous episodes of nausea and vomiting. Intervention: Use of neurally adjusted ventilatory assist to avoid patient-ventilator dyssynchrony and consequent gastric distension. Conclusions: The utilization of neurally adjusted ventilatory assist allowed to limit the risk of overassistance and prevent patient-ventilator asynchrony and to successfully wean the child off mechanical ventilation after single-lung transplant.

Initial Single-Center Experience With Levosimendan Infusion for Perioperative Management of Univentricular Heart With Ductal-Dependent Systemic Circulation:

The aim of this study was to evaluate the safety and the efficacy of levosimendan, a novel calcium sensitizer agent, on postoperative hemodynamic and metabolic parameters of neonates affected by single ventricle anatomy. Twenty consecutive neonates scheduled for the Norwood procedure with Blalock Taussig shunt were prospectively enrolled. All patients received an infusion of levosimendan at 0.1 μg/kg/min commencing 24 hours before surgery, and the infusion was continued for 48 hours after surgery. No side effects (intolerance to the drug, hypotension, arrhythmias) were shown. A median inotropic score (IS) of 37 was necessary to maintain a mean arterial pressure between 45 and 50 mm Hg at intensive care unit (ICU) admission: IS was significantly reduced after 72 hours (P < .05). Brain natriuretic peptide values decreased significantly from 1210 to 459 pg/mL in 72 hours (P < .05). Median SvO2 increased significantly from 38% to 59% during the evaluated period (P < .05). Cerebral near-infrared spectroscopy values were close to 40% at ICU admission with a significant stable increase to 50% after 12 hours (P < .05). Median lactate level was 13 mmol/L at ICU admission but showed a trend to a rapid and significant decrease after 12 hours (P < .05). Median urine output was surprisingly elevated, always remaining between 5.2 and 6.2 mL/kg/h throughout the postoperative period. Survival rate was 85% at 30 days (17/20 patients) and 75% (15/20) at hospital discharge. Levosimendan infusion in a cohort of neonates with univentricular anatomy was safe and potentially beneficial on postoperative hemodynamic and metabolic parameters.

Preoperative use of steroids in pediatric cardiac surgery: new directions for future research?

We read with great interest the work of Heying and colleagues [1]. The authors showed that dexamethasone administration before an arterial switch operation provided downregulation of proinflammatory and upregulation of antiinflammatory cytokines, lowering myocardial cell damage. This important conclusion, despite the low number of patients and the single type of cardiac operation, was consistently sustained by the study of intramyocardial messenger riboneucleic acid expression of cytokines involved in myocardial damage. However, recently, Pasquali and associates [2] published a multicenter observational analysis in which they did not find a significant benefit associated with any regimen of methylprednisolone examined, and they also found an increased rate of infection in the “low”-surgical-risk group. In the past 10 years, other authors [3–7] have discussed steroid efficacy in pediatric cardiac surgical procedures. Such studies seem to show heterogeneous results and do not allow any definitive conclusion to be drawn about the safety and efficacy of steroid use as well as the timing, dosing regimen, and specific indications in pediatric cardiac operations. Our opinion is that, regardless of diffuse steroid use before cardiopulmonary bypass, scientific equipoise currently warrants, as soon as possible, a large randomized clinical trial of steroid treatment, targeting both the biochemical and the clinical outcomes. Such a trial is currently a priority to optimize, or finally exclude from clinical practice, agents to modulate systemic inflammatory response syndrome after cardiopulmonary bypass.