Robert Sümpelmann

Comparison of electrical velocimetry and transpulmonary thermodilution for measuring cardiac output in piglets

Background:  Monitoring of cardiovascular function is essential during major pediatric and pediatric cardiac surgery. Invasive monitoring of cardiac output (CO) and oxygen delivery is expensive and sometimes associated with adverse events. Therefore, we investigated the accuracy of a new noninvasive CO monitoring device using electrical velocimetry (EV) in comparison with the more invasive transpulmonary thermodilution (TPTD) method.

European consensus statement for intraoperative fluid therapy in children.

The intraoperative infusion of isotonic solutions with 1-2.5% glucose in children is considered well established use in Europe and other countries. Unfortunately, a European marketing authorisation of such a solution is currently missing and as a consequence paediatric anaesthetists tend to use suboptimal intravenous fluid strategies that may lead to serious morbidity and even mortality because of iatrogenic hyponatraemia, hyperglycaemia or medical errors. To address this issue, the German Scientific Working Group for Paediatric Anaesthesia suggests a European consensus statement on the composition of an appropriate intraoperative solution for infusion in children, which was discussed during a working session at the 2nd Congress of the European Society for Paediatric Anaesthesiology in Berlin in September 2010. As a result, it was recommended that an intraoperative fluid should have an osmolarity close to the physiologic range in children in order to avoid hyponatraemia, an addition of 1-2.5% instead of 5% glucose in order to avoid hypoglycaemia, lipolysis or hyperglycaemia and should also include metabolic anions (i.e. acetate, lactate or malate) as bicarbonate precursors to prevent hyperchloraemic acidosis. Thus, the underlying intention of this consensus statement is to facilitate the granting of a European marketing authorisation for such a solution with the ultimate goal of improving the safety and effectiveness of intraoperative fluid therapy in children.

A novel isotonic-balanced electrolyte solution with 1% glucose for intraoperative fluid therapy in children: results of a prospective multicentre observational post-authorization safety study (PASS): A NOVEL ISOTONIC BALANCED ELECTROLYTE SOLUTION WITH 1% GLUCOSE

Background:  The recommendations for intraoperative fluid therapy in children have been adapted from hypotonic to isotonic electrolyte solutions with lower glucose concentrations (1–2.5% instead of 5%) to avoid hyponatremia and hyperglycemia.

Hydroxyethyl starch 130/0.42/6:1 for perioperative plasma volume replacement in 1130 children: results of an European prospective multicenter observational postauthorization safety study (PASS): HES 130 for plasma replacement in children

Introduction:  Third‐generation hydroxyethyl starch (HES) is now approved also for the use in children, but safety studies including large numbers of pediatric patients are still missing. Therefore, we performed an European multicentric prospective observational postauthorization safety study (PASS) to evaluate the use of HES 130/0.42/6:1 in normal saline (ns‐HES) or a balanced electrolyte solution (bal‐HES) in children undergoing surgery.

The pediatric cardiac patient presenting for noncardiac surgery.

Purpose of review To summarize results of recent papers and discuss current trends concerning anesthesia in children with congenital heart disease presenting for noncardiac surgery. Recent findings Children with congenital heart disease have a significant incremental risk when presenting for minor or major surgery. It is a current trend that noncardiac surgery should be performed in pediatric centers, which have anesthesiologists and pediatricians familiar with the multiple specialties of children with congenital heart disease. A careful preoperative evaluation using a multidisciplinary approach is of great importance. In recent studies and case reports, the safe use of newer anesthetic agents, such as sevoflurane or desflurane, was reported in combination with opioids or regional blocks. In addition to standard monitors, invasive monitoring should be considered liberally perioperatively in patients with limited hemodynamic reserve and with major surgery. Several case reports reported that laparoscopic surgery was successfully performed even in high-risk patients with congenital heart disease. Summary Careful preoperative evaluation, experienced anesthesiologists, suitable anesthetic agents and techniques, and the liberal use of invasive monitoring are integral parts of safe and effective anesthetic care in children with congenital heart disease. Future studies have to show whether laparoscopic surgery may be beneficial in this special subgroup of patients.

Safety of glucose-containing solutions during accidental hyperinfusion in piglets

BACKGROUND Errors in fluid management can lead to significant morbidity in children. We conducted an experimental animal study to determine the margin of safety in accidental hyperinfusion of different glucose and electrolyte containing solutions. METHODS Fifteen piglets [bodyweight 12.1 (sd 2.0) kg] were randomly assigned to receive either 100 ml kg⁻¹ of balanced electrolyte solution with glucose 1% (BS-G1), hypotonic electrolyte solution with glucose 5% (HE-G5), or glucose 40% solution (G40) over 1 h. Blood electrolytes, glucose, and osmolality and intracranial pressure (ICP) were measured before, during, and after fluid administration. RESULTS Hyperinfusion of BS-G1 led to moderate hyperglycaemia [baseline 3.4 (sd 1.3) mmol litre⁻¹, study end 12.6 (1.8) mmol litre⁻¹], but no other relevant pathophysiological alterations. Hyperinfusion of HE-G5 produced marked hyperglycaemia [baseline 3.9 (1.2) mmol litre⁻¹, study end 48.6 (4.3) mmol litre⁻¹, P < 0.05] and hyponatraemia [baseline 136.4 (1.3) mmol litre(-1), study end 119.6 (2.1) mmol litre⁻¹, P < 0.05], whereas osmolality remained stable during the course of the study. Hyperinfusion of G40 induced acute hyperglycaemic/hyperosmolar decompensation with an extreme decrease in serum electrolytes [e.g. sodium baseline 138 (1.1) mmol litre⁻¹, 30 min 87.8 (6.4) mmol litre⁻¹, P < 0.01], leading to cardiac arrest after infusion of 50-75 ml kg⁻¹. ICP remained within a physiological range in all groups. CONCLUSIONS In an animal model of accidental hyperinfusion, BS-G1 showed the widest margin of safety and can therefore be expected to enhance patient safety in perioperative fluid management in children; HE-G5 proved significantly less safe; and G40 was found to be outright hazardous.

Hydrocortisone does not affect major platelet receptors in inflammation in vitro

HYPOTHESIS Platelet function is an important factor for the fate of intensive care patients. Several factors may influence this function. Recently, it was demonstrated that hydrocortisone has immunologic effects in septic shock and therefore may affect cell adhesion molecules. The aim of the present study was to examine effects of hydrocortisone on platelet receptor expression in healthy individuals and septic patients in vitro. METHODS Citrated blood samples were drawn from 10 healthy volunteers and 10 septic patients. Samples were adjusted with hydrocortisone to final concentrations of 4.5 microg mL(-1), 9.0 microg mL(-1) (sepsis-equivalent bolus) and 90 microg mL(-1), respectively. A control group received no additional hydrocortisone. Expression of CD62P, CD41, PAC-1 and CD42b on the surface of resting or agonist-stimulated platelets was determined by whole blood flow cytometry using fluorescence-labeled monoclonal antibodies. RESULTS Hydrocortisone had no significant influence on the expression of CD62P, CD41 and PAC-1. After administration of 90 microg mL(-1) hydrocortisone the expression of CD42b was decreased compared to controls after activation. Differences between volunteers and sepsis patients were found for all receptors after activation. CONCLUSIONS Hydrocortisone mediates immunmodulating effects in therapy of patients suffering of septic shock without involvement of specific platelet receptors in vitro.

Prevention of intraoperative hypothermia in neonates and infants: results of a prospective multicenter observational study with a new forced-air warming system with increased warm air flow.

Neonates and infants are at the highest risk of developing perioperative hypothermia. A number of methods to prevent hypothermia during pediatric anesthesia are in use, and despite the fact that conventional forced‐air warmers are the most effective devices, they are not always sufficient enough to maintain body temperature. Therefore, recently a new forced‐air warming system with an increased warm air flow was introduced to the market.

Comparison of cardiac output measurements by arterial trans-cardiopulmonary and pulmonary arterial thermodilution with direct Fick in septic shock

Background and objective: The aim of this study was to compare cardiac output (CO) measurements by arterial trans‐cardiopulmonary thermodilution (ATD) and pulmonary arterial thermodilution (PATD) with CO estimated on the basis of the Fick calculation via a metabolic monitor in septic shock. Methods: In a prospective animal study 20 anaesthetized, ventilated pigs (20.9 ± 1.9 kg) were investigated. Septic shock was induced with faecal peritonitis. A pulmonary artery catheter was used for conventional measurement of CO. Simultaneously ATD was measured with a thermistor tipped catheter inserted into right carotid artery. Whole body oxygen consumption was measured by indirect calorimetry. Eighty data pairs of simultaneous CO measurements were analysed. Results: CO measured with Fick and that measured with PATD were significantly correlated (r = 0.94, r2 = 0.87, P < 0.001). Mean CO measured by PATD was 94.3 ± 40.1 mL min−1 kg−1. Bias was 10.1 mL min−1 kg−1 (95% confidence interval (CI): 6.0‐14.2 mL min−1 kg−1) with limits of agreement of −26.8 to 47.0 mL min−1 kg−1. Correlation between Fick derived CO estimation and ATD CO was similar (r = 0.91, r2 = 0.83, P < 0.001). Mean CO measured by trans‐cardiopulmonary thermodilution was 104.3 ± 43.2 mL min−1 kg−1. Bias was 0.75 mL min−1 kg−1 (95% CI: −3.8 to 5.3 mL min−1 kg−1) with limits of agreement of −39.7 to 41.2 mL min−1 kg−1. Conclusions: Even during haemodynamic instability in septic shock the correlation of arterial trans‐cardiopulmonary thermodilution and PATD derived CO with direct Fick was good. As arterial trans‐cardiopulmonary thermodilution is less invasive than PATD, the former may offer practical advantages.

Cardiac output measurement by arterial thermodilution in piglets.

M easuring cardiac output (CO) in critically ill infants is often helpful after major cardiac surgery because surgical outcome may be improved by maintaining adequate CO (1). The measurement of CO by using a pulmonary artery catheter (PAC) in small infants, especially in those of ,10 kg, is rarely used because of technical difficulties of placement, invasiveness, and potential complications. The recent development of a small arterial thermistortipped catheter may overcome some of the technical problems associated with central cannulation and catheterization of the pulmonary artery. Insertion of such a catheter can be performed into the femoral or axillary artery through a 22-gauge cannula (2).The aim of this investigation was to evaluate the accuracy of CO measurements in piglets of 10.2 6 1.1 kg obtained by arterial trans-cardiopulmonary thermodilution (ATD) by using an arterial thermistor-tipped catheter compared with conventional pulmonary arterial thermodilution (PATD) by using a PAC.