Assessment of stress response attenuation with caudal morphine using a surrogate marker during pediatric cardiac surgery.

BACKGROUND: Measurement of biomarkers representing sympathetic tone and the surgical stress response are helpful for objective comparison of anesthetic protocols. AIMS: The primary aim was to compare changes in chromogranin A levels following pump pediatric cardiac surgery between children who received bolus caudal morphine and those who received a conventional intravenous narcotic-based anesthesia regime. The secondary objectives were to compare hemodynamic responses to skin incision and the magnitude of the rise in blood sugar values between the groups. SETTINGS AND DESIGN: A prospective observational study at a tertiary cardiac center. MEASUREMENTS AND METHODS: Sixty pediatric cardiac surgical patients were randomized to Group I [n= 30] to receive intravenous narcotic-based anesthesia and Group II [n = 30] to receive single-shot caudal morphine. Baseline and postoperative chromogranin A levels, the hemodynamic response to skin incision, changes in blood sugar levels, and the total intravenous narcotic dose administered were recorded for each participant. STATISTICAL ANALYSIS: Pearson's Chi-squared test was used for comparison of categorized variables, and Mann-Whitney test was used for the analysis of continuous data. RESULTS: Changes in chromogranin A levels and blood sugar levels were comparable in both groups. Group II received a lower narcotic dosage (P ≤ 0.001), and the response to skin incision as reflected by systolic pressure rise was less (P = 0.006). CONCLUSIONS: Surgical stress response attenuation was similar to caudal morphine as compared with intravenous narcotic-based anesthesia techniques as reflected by a similar increase in chromogranin A levels.

The Optimal Length of Insertion for Central Venous Catheters Via the Right Internal Jugular Vein in Pediatric Cardiac Surgical Patients.

OBJECTIVES: The primary objective was to identify the best among 4 techniques that could predict the length of central venous catheter insertion through the right internal jugular vein, which, in turn, would ensure the ideal placement of the catheter tip in pediatric cardiac surgical patients. The techniques evaluated were those based on operator experience, topography/landmark methods, and one that relied on a patient's height-related formula. Based on the outcome of the study, the possibility of arriving at a formula was investigated that would predict with reasonable certainty the ideal length of catheter to be inserted for the correct catheter placement through the right internal jugular vein in pediatric cardiac surgical patients belonging to the authors' geographic area. DESIGN: A prospective observational study. SETTING: Tertiary care cardiac center. PARTICIPANTS: Children younger than 5 years of age undergoing cardiac surgery. INTERVENTIONS: Right internal jugular vein cannulation by the Seldinger technique method. MEASUREMENTS AND MAIN RESULTS: A total of 120 children aged younger than 5 years undergoing cardiac surgery were included in the study. The participants were randomized to 4 groups: group 1 (n = 30), the length of the central venous catheter was determined empirically by the operator based on clinical experience; group 2 (n = 30), the depth of insertion of the catheter was determined by the distance from the site of skin puncture to the second intercostal space; group 3 (n = 30), the depth of insertion of the catheter was determined by the distance from the skin puncture site to the third intercostal space; and group 4 (n = 30), the length of catheter was determined by a height-based formula that was followed routinely at the authors' institution. Central venous catheterization through the right internal jugular vein was performed according to out-of-plane ultrasound guidance in all patients. The ideal catheter tip location was assumed to be at the level of the carina or within 1.5 cm proximal to it. The number of patients who had ideal catheter tip placement were recorded from postoperative chest radiograph in all groups. Any relationship between acceptable catheter tip and demographic data (mean ranks of age, height, weight, and body surface area) of the patients were studied. RESULTS: The central vein catheter tip was at the level of the carina or within 1.5 cm in more patients in group 2 (39%, p = 0.02) compared with the other groups. This was followed by group 4 (40%), group 3 (30%), and group 1 (23%). There was a statistically significant difference in the mean distance between catheter tip and carina, with group 2 patients having the tip closest to the carina (p = 0.03). There was a significant correlation between acceptable catheter tip positioning and a patient's height (p = 0.04). A new formula was developed based on this correlation. CONCLUSIONS: A landmark-based topographic method in which the length of insertion of the catheter was determined by the distance from the skin puncture site to the second intercostal space for achieving correct placement of the catheter tip was found to be more reliable compared with other techniques. Height-based formula has the disadvantage of being affected by the skin puncture site. Assuming that a skin puncture at the midpoint between the right mastoid process and clavicular insertion of sternocleidomastoid muscle insertion is ensured, a new formula based on height has been proposed.