Marco Marano

Relationship between global end-diastolic volume and cardiac output in critically ill infants and children

Objective:The objective of this study was to investigate possible correlations between the preload index global end-diastolic volume (GEDV) and the indexes of cardiac function, cardiac index, and stroke volume index in critically ill pediatric patients. The aim was to evaluate whether GEDV may help in the decision-making process concerning volume loading. Design:Prospective clinical study. Setting:Pediatric intensive care unit of the Bambino Gesù Children’s Research Hospital. Patients:Seventy patients, 40 male and 30 female, mean age 62 ± 41 months (range 5–156 months), divided into six groups: group A, hemorrhagic shock, ten cases; group B, head injury, 21 cases; group C, septic shock, ten cases; group D, encephalitis, ten cases; group E, respiratory failure, nine cases; group F, cardiogenic shock, ten cases. Interventions:All patients received volumetric hemodynamic monitoring following initial resuscitation and every 4 hrs thereafter or whenever a hemodynamic deterioration was suspected. During the cumulative in-hospital stay, a total 1,184 sets of measurements were done. Measurements and Main Results:Findings are consistent with a statistically significant linear correlation of GEDV with cardiac index and stroke volume index in hemorrhagic shock (group A) (R2 = .647, p < .0001; R2 = .738, p < .0001) and cardiogenic shock (group F) (R2 = .645, p < .0001; R2 = .841, p < .0001). Conclusions:GEDV may potentially be a useful guide to treatment in preload-dependent conditions, such as hemorrhagic and cardiogenic shock. In the other groups where there is little relationship between preload and cardiac function indexes, the influence of non-preload-dependent mechanisms on cardiac output is certainly more significant.

Ultrasound-guided central venous cannulation in infants weighing less than 5 kilograms

Purpose Recent reports suggest that ultrasound-guided central venous cannulation may also be safe and effective in infants. This study aimed to evaluate the success and complications rate of this technique in infants weighing less than 5 kg. Methods We studied 45 infants, weighing less than 5 kg (mean weight: 2.9 ± 1.1 kg, median: 3.1) needing a central venous access for intensive care treatment. In all patients, venous access was obtained by ultrasound-guided cannulation of the internal jugular vein (IJV). Results Central venous cannulation was successful in all 45 infants. The right internal jugular vein (IJV) was used in most cases (92%). The IJV was antero-lateral to the carotid artery in 66% of patients, lateral in 28% and anterior in 6%. Although we recorded 10 complications (22.2%), only one was clinically relevant (one pneumothorax). The other complications were repeated venipunctures (n=4), kinking of the guidewire (n=3) and local venous hematomas (n=2). The time required for completing the procedure was 7 ± 4.3 min, while the mean time of central venous catheter permanence was 5.5 ± 8 days. There was a negative correlation between the patients weight and the time needed for cannulation (p<0.01). Complications occurred in infants with a lower body weight (p<0.01). Conclusions Our experience suggests that ultrasound-guided central vein cannulation can be performed by well-trained physicians in infants weighing less than 5 kg without relevant risks.

ECLS in Pediatric Cardiac Patients

Extracorporeal life support (ECLS) is an important device in the management of children with severe refractory cardiac and or pulmonary failure. Actually, two forms of ECLS are available for neonates and children: extracorporeal membrane oxygenation (ECMO) and use of a ventricular assist device (VAD). Both these techniques have their own advantages and disadvantages. The intra-aortic balloon pump is another ECLS device that has been successfully used in larger children, adolescents, and adults, but has found limited applicability in smaller children. In this review, we will present the “state of art” of ECMO in neonate and children with heart failure. ECMO is commonly used in a variety of settings to provide support to critically ill patients with cardiac disease. However, a strict selection of patients and timing of intervention should be performed to avoid the increase in mortality and morbidity of these patients. Therefore, every attempt should be done to start ECLS “urgently” rather than “emergently,” before the presence of dysfunction of end organs or circulatory collapse. Even though exciting progress is being made in the development of VADs for long-term mechanical support in children, ECMO remains the mainstay of mechanical circulatory support in children with complex anatomy, particularly those needing rapid resuscitation and those with a functionally univentricular circulation. With the increase in familiarity with ECMO, new indications have been added, such as extracorporeal cardiopulmonary resuscitation (ECPR). The literature supporting ECPR is increasing in children. Reasonable survival rates have been achieved after initiation of support during active compressions of the chest following in-hospital cardiac arrest. Contraindications to ECLS have reduced in the last 5 years and many centers support patients with functionally univentricular circulations. Improved results have been recently achieved in this complex subset of patients.

Ultrasound-guided left brachiocephalic vein cannulation in children with underlying bleeding disorders: A retrospective analysis

Objectives: To evaluate the safety and effectiveness of ultrasound–guided left brachiocephalic vein cannulation in infants and children with underlying bleeding conditions. Design: Retrospective cohort. Setting: PICU of a tertiary pediatric hospital. Patients: Thirty-four patients requiring central venous catheterization from January 2011 to January 2012. Interventions: None. Measurements and Main Results: Two pediatric intensivists, experienced in ultrasound–guided vessel cannulation, performed the ultrasound catheterization of the left brachiocephalic vein. Ultrasound equipment consisted of a standard ultrasound monitor with a linear 6–13 MHz probe. The ultrasound monitor was set on a resolution with a depth of 1.8 cm for infants and 2.2 cm for children. The “in-plane” technique was used for all patients. Thirty-four catheterizations were performed. Patient median age was 12.5 months (5.75–63.5 mo) and median weight was 9.25 kg (7–16.25 kg). The population of infants and children analyzed was composed of 25 patients with hematologic disorder (73%) treated with hematopoietic stem cell transplantation, five patients (15%) supported with extracorporeal membrane oxygenation for viral pneumonias, and four patients (12%) with uremic hemolytic syndrome. A 4F catheter was used in 79% of cases. Left brachiocephalic vein cannulation was successful in all 34 patients. Median time needed for cannulation was 350 seconds (277.5–450 s). The overall complication rate was 9% (3 of 34) and consisted of difficulty in advancing the guidewire after having pierced the vein. The time required for catheter positioning and complications was not associated with both lower body weight and body surface area of the patients (p > 0.05). Mean central venous catheter duration was 32 ± 4 days. Conclusions: Data reported in this retrospective study confirm the safety and effectiveness of ultrasound–guided left brachiocephalic vein catheterization in infants and children with underlying bleeding disorders.

Independent lung ventilation in a newborn with asymmetric acute lung injury due to respiratory syncytial virus: A case report

IntroductionIndependent lung ventilation is a form of protective ventilation strategy used in adult asymmetric acute lung injury, where the application of conventional mechanical ventilation can produce ventilator-induced lung injury and ventilation-perfusion mismatch. Only a few experiences have been published on the use of independent lung ventilation in newborn patients.Case presentationWe present a case of independent lung ventilation in a 16-day-old infant of 3.5 kg body weight who had an asymmetric lung injury due to respiratory syncytial virus bronchiolitis. We used independent lung ventilation applying conventional protective pressure controlled ventilation to the less-compromised lung, with a respiratory frequency proportional to the age of the patient, and a pressure controlled high-frequency ventilation to the atelectatic lung. This was done because a single tube conventional ventilation protective strategy would have exposed the less-compromised lung to a high mean airways pressure. The target of independent lung ventilation is to provide adequate gas exchange at a safe mean airways pressure level and to expand the atelectatic lung. Independent lung ventilation was accomplished for 24 hours. Daily chest radiograph and gas exchange were used to evaluate the efficacy of independent lung ventilation. Extubation was performed after 48 hours of conventional single-tube mechanical ventilation following independent lung ventilation.ConclusionThis case report demonstrates the feasibility of independent lung ventilation with two separate tubes in neonates as a treatment of an asymmetric acute lung injury.

Severe parainfluenza pneumonia in a case of transient hypogammalobulinemia of infancy.

Human parainfluenza viruses (HPIVs) infection, largely known to cause self-limiting bronchiolitis and pneumonia in immune competent patients, can lead to severe to fatal pulmonary disease in immune disorders, such as primary or acquired-immune deficiencies. We report the case of a 1-year-old child who developed an acute respiratory distress syndrome. Because of a progressive respiratory failure unresponsive to conventional treatment extracorporeal membrane oxygenation (ECMO) was rapidly started. HPIV-3 infection was diagnosed on the rhinopharyngeal fluid and immunological examinations revealed a hypogammaglobulinemia. A combination therapy with ribavirin, intravenous immunoglobulin (IVIG) and steroid under ECMO support was started with considerable improvement. Subsequent analysis and more specific immunological assessment resulted normal confirming the diagnosis of transient hypogammaglobulinemia of infancy (THI). This case highlights the importance of prompt therapy with early ECMO support in combination with ribavirin, IVIG and steroids in patients affected by severe HPIV-3 pneumonia and THI.

Case 1: Chocolate-coloured blood in infant with shock (Case Presentation)

CASE PRESENTATION We report the case of a 6-month-old infant (body weight 6 kg), transferred to our intensive care unit (ICU) from a district general hospital with the diagnosis of septic shock. Upon arrival at our institution she was ventilated in a pressure-controlled mode reaching a peripheral Spo2 of 90% with a Fio2 of 100%, associated with a peripheral pallid cyanosis. Haemodynamic conditions were unstable: blood pressure 60/20 mmHg, heart rate 170 beats/min, refill capillary time >4 sec, reduced cardiac inotropic performance at trans-thoracic echocardiography without congenital anomaly. Neurologic examination showed a paediatric Glascow coma score (GCS) of 8, isocoric and isociclic pupils scarcely reacting to light bilaterally. Arterial blood gases showed a severe metabolic acidosis: pH: 7, Pao2, 218 mmHg, PaCo2, 14 mmHg, EB, −25. Blood haemoglobin was 9 g/L, leukocyte count 35 000/103 mcL, serum levels of sodium, potassium, calcium, phosphorus, urea, creatinine, liver enzymes, reactive C protein were within normal limits. A chest X-ray showed normal cardiac silhouette and clear lung fields. No signs of infections seemed to be present. Blood samples were brown coloured. After fluid administration of 20 mL/kg in 20 min of cristalloids and inotropic support (dopamine 10 g/kg/min) haemodynamic conditions progressively worsened leading to a cardiac arrest with asystolia. Cardiopulmonary resuscitation was successfully performed with a ROSC time of 100 sec. At this moment we were able to perform a better evaluation of patient’s clinical case history taken from the parents (they referred that the infant, previously healthy, progressively decreased her consciousness and that she was fed with a vegetable soup prepared in advance and stored in the refrigerator 2 days before admission to ICU). What caused her symptoms?

Pediatric extracorporeal cardiopulmonary resuscitation settled in an emergency department for a propafenone intentional intoxication

ABSTRACT The use of drugs in suicide attempts is becoming more and more frequent among adolescents. Intentional intoxication with propafenone is very rare and mainly reported in adults associated with other drugs. The therapeutic approach is symptomatic, since there is no specific antidote for propafenone. We present a pediatric case of intentional ingestion of 1.8 g of propafenone that caused refractory cardiogenic shock. The patient was successfully rescued with extracorporeal cardiopulmonary resuscitation in the emergency department of a secondary level peripheral hospital.

Letter in response to: “Hyperglycemia is a risk factor for high-grade envenomations after European viper bites (Vipera spp.) in children”

We read with great interest the retrospective study by Claudet et al., on the consideration hyperglycemia as risk factor for high-grade envenomations after European viper bites (Vipera spp.) in children.[1] Hyperglycemia associated with inflammatory and/or stressful conditions secondary to acute injury has been described since the nineteenth century. In particular, stress hyperglycemia (SH) may be secondary to a stress response in patients with severe diseases (e.g., sepsis, trauma, poisonings), and it can be induced mainly by pain, acidosis, alteration in intravascular volume and hypoxia. As cited by Claudet et al. adrenergic hyperstimulation plays a key role in causing hyperglycemia and this toxic mechanism is well documented in other envenomations (e.g., scorpion envenomation). However, some aspects needs to be clarified. The definition of hyperglycemia used by Claudet et al. shows a parameter that is not defined a priori and is reported only in the discussion and it is not supported by reference. The Authors considers hyperglycemia in nondiabetic children as ‘‘glycemia over 6.1 mmol/L when fasting or over 7.7 mmol/L 2 hours after a meal.’’ Based on scientific literature SH in nondiabetic, pediatric critical illness is defined as a blood glucose (BG) value greater than 7.0 mmol/L (126 mg/dL),[2] and key studies consider SH if BG is greater than 8.3 mmol/L (150 mg/dL).[3] Therefore, if we consider the SH cutoff of 8.3 mmol/L, only three patients (8.8, 8.9 and 9.4 mmol/L) studied by Claudet et al. and with high grade of envenomation should be considered as patients with hyperglycemia. In consideration of these comments, statistical results should be reconsidered. Another aspect not sufficiently discussed is the timing of glycemia detection, this is essential if we are to consider this as early risk factor parameter influencing clinical management. In the case series, hyperglycemia was recorded also extremely late after the viper bites – even after 12 hours – and this could be mainly related to the inflammatory and stress condition secondary to severe envenomation. Moreover, hyperglycemic patient presenting with low-grade envenomation (and with glycaemia of 6.7 mmol/L under fasting condition) is not correctly represented in Figure 1 of Claudet et al’s article.[1]. In our experience (10 years’ study period), in the Pediatric Emergency Department, seven (nondiabetic) patients were classified as severe viper envenomation (GSS II: 6pts, GSSIII: 1pt). Only in two patients, during the first 12 hours and before any intravenous infusion, glycemia was higher than 8.3 mmol/L (150 mg/dl), respectively, (GSSII 8.88 mmol/L, GSSIII 8.89 mmol/L). We think that envenomed pediatric patients by European viper bite with highest severity score (GSS Grade II and III) may suffered from SH as documented in acute illness.[4] At present, hyperglycemia in severe envenomed pediatric patient should be considered cautiously as a specific risk factor because of the extremely variability of this parameter. In our opinion, further studies should be required to assess whether these findings apply to routine clinical practice. To reach this goal, a prospective multicenter study could be seriously considered.

Treatment of boric acid overdose in two infants with Continuous Venovenous Hemodialysis.

There is no agreement on the treatment of this intoxication, mainly depending on the lack of correlation between blood levels and clinical outcome. To date, no cases of boric acid intoxication treated with Continuous Venovenous Hemodialysis (CVVHD) has been reported, despite the good hemodynamic tolerance provided by this modality. We present two infants treated with CVVHD after accidental ingestion of boric-acid-saturated water to prepare milk formula. Case 1: Nine hours after accidental ingestion of 655 mg/ kg of boric acid, a 3-month infant showed moderate dehydration, prolonged capillary refi ll time, tachypnea, tachycardia, and oliguria, requiring intravenous fl uid therapy. No organ failure occurred. Case 2: A 40-day-old girl was accidentally fed with 3 consecutive meals containing a total of 2570 mg/kg of boric acid. Third ingestion induced vomiting. After admission at local hospital, she looked responsive, with moderate dehydration and acidosis and was treated with intravenous fl uids to induce forced diuresis. At admission in our hospital, she was irritable, tachycardic, with elevated blood pressure, normal hydration, and no evidence of organ failure. Patients ’ blood analysis and vital signs at admission in pediatric intensive care unit (PICU) are shown in Table 1. Normalization of arterial blood gas occurred approximately 9 hours after the fi rst determination in both cases. Even if in small children HD provides highest boric acid clearance, it induces hemodynamic instability. 3 Given the high clearance by diffusion of CVVHD and the better hemodynamic tolerance provided by this modality, CVVHD was started 14 and 21 hours after last ingestion, respectively, considering persistent oliguria in fi rst case and the elevated amount of boric acid ingested in both patients. A 6.5F, 7.5-cm double-lumen catheter was placed into jugular vein after intubation and sedation with Midazolam and Remifentanil. In case 1, CVVHD was performed with blood fl ow (Qb) of 50 ml/min and dialysate fl ow (Qd) of 2000 ml/h for 36 hours with an Aquarius ® CRRT monitor equipped with a 0.3-m 2 polysulfone fi lter (Aquamax ® HF03, Edwards Lifesciences S.A — St Prex — Switzerland); in case 2, it was performed with Qb 30 ml/min and Qd 600 ml/h for 38 hours, using a 0.2-m 2 AN69 fi lter (HF20 ® , Gambro Lundia AB, Sweden) with Prismafl ex ® CRRT monitor equipped with pediatric software (Gambro Lundia AB, Sweden). During CVVHD, hemodynamic function was stable, except for a bradycardia at the start of CVVHD in patient 1, which required its temporary interruption. No neurological or other sequelae were observed and patients were discharged from PICU 7 and 9 days after the admission, respectively. Effl uent dialysate was collected in the bags provided in the circuit. Bags were weighted and total volume (V) was derived. Boric acid concentration was determined by an inductively coupled plasma mass spectrometer (ELAN 6100 DRCII ICP-MS; Perkin-Elmer SCIEX Instruments, Concord, Ontario, Canada) equipped with a dynamic reaction cell, a quadrupole mass fi lter, cyclonic spray chamber with a concentric nebulizer, and AS 90plus auto-sampler (Perkin-Elmer). Calibration was performed by “ standard addition ” method. Standard solutions were prepared from 1000 mg of L-1 boron calibration standard (VWR International LTD.), by dilution with water containing the same amount of acids as the samples. CVVHD clearance was calculated as V * BAd/BAp, where V * BAd (boric acid in the effl uent dialysate) is mass removal and BAp is the time average plasma concentration derived from the preand post-CVVHD boric acid concentrations. After oral ingestion, boric acid is rapidly and completely absorbed reaching the highest concentrations in brain and liver 2 . More than 90% is excreted unchanged by the kidneys within 96 hours. 2,4 – 5