Adrenal insufficiency in children undergoing heart surgery does not correlate with more complex postoperative course.

Although some evidence suggests benefit of steroid supplementation after pediatric cardiac surgery, data correlating adrenal function with the postoperative course is scarce. This study sought to determine if adrenal insufficiency (AI) after cardiac surgery is associated with a more complicated postoperative course in children. A prospective study was performed during a 6-month period at a pediatric medical center. Included were 119 children, 3 months and older, who underwent heart surgery with cardiopulmonary bypass. Cortisol levels were measured before and 18 h after surgery. Patients were divided into two groups by procedure complexity (low or high), and clinical and laboratory parameters were compared between patients with and without AI within each complexity group. In the low-complexity group, 45 of the 65 patients had AI. The normal adrenal function (NAF) subgroup had greater inotropic support at 12, 24, and 36 h after surgery and a higher lactate level at 12 and 24 h after surgery. There were no significant differences between subgroups in duration of ventilation, sedation, intensive care unit (ICU) stay, or urine output. In the high-complexity group, 27 patients had AI, and 27 did not. There were no significant differences between subgroups in inotropic support or urine output during the first 36 h or in mechanical ventilation, sedation, or ICU stay duration. Children with AI after heart surgery do not have a more complex postoperative course than children with NAF. The adrenal response of individual patients seems to be appropriate for their cardiovascular status.

Role of C-reactive protein velocity in the diagnosis of early bacterial infections in children after cardiac surgery.

Fever after cardiac surgery in children may be due to bacterial infection or noninfectious origin like systemic inflammatory response syndrome (SIRS) secondary to bypass procedure. A marker to distinguish bacterial from nonbacterial fever in these conditions is clinically important. The purpose of our study was to evaluate, in the early postcardiac surgery period, whether serial measurement of C-reactive protein (CRP) and its change over time (CRP velocity) can assist in detecting bacterial infection. A series of consecutive children who underwent cardiac surgery with bypass were tested for serum levels of CRP at several points up to 5 days postoperatively and during febrile episodes (>38.0°C). Findings were compared among febrile patients with proven bacterial infection (FWI group; sepsis, pneumonia, urinary tract infection, deep wound infection), febrile patients without bacterial infection (FNI group), and patients without fever (NF group). In all, 121 children were enrolled in the study, 31 in the FWI group, 42 in the FNI group, and 48 patients in the NF group. Ages ranged from 4 days to 17.8 years (median 19.0, mean 46 ± 56 months). There was no significant difference among the groups in mean CRP level before surgery, 1 hour, and 18 hours after. A highly significant interaction was found in the change in CRP over time by FWI group compared with FNI group (P < .001). Mean CRP velocity ([fCRP - 18hCRP]/[fever time (days) - 0.75 day]) was significantly higher in the infectious group (4.0 ± 4.2 mg/dL per d) than in the fever-only group (0.60 ± 1.6 mg/dL per d; P < .001). A CRP velocity of 4 mg/dL per d had a positive predictive value (PPV) of 85.7% for bacterial infection with 95.2% specificity. Serial measurements of CRP/CRP velocity after cardiac surgery in children may assist clinicians in differentiating postoperative fever due to bacterial infection from fever due to noninfectious origin.

Procalcitonin level as an aid for the diagnosis of bacterial infections following pediatric cardiac surgery.

PURPOSE: The aim of the present study was to determine if blood procalcitonin can serve as an aid to differentiate between bacterial and nonbacterial cause of fever in children after cardiac surgery. MATERIALS AND METHODS: A nested case-control study of children who underwent open cardiac surgery in critical care units of fourth-level pediatric hospital was performed. Blood samples for procalcitonin level were collected 1 day before operation; 1 hour postoperation; on postoperative days 1, 2, and 5; and on the day of fever, when it occurred. RESULTS: Of 665 children who underwent cardiac bypass surgery, 126 had a febrile episode postoperatively, 47 children with a proven bacterial infection and 79 without bacterial infection. Among the 68 children in whom fever developed within the first 5 postoperative days, procalcitonin level at fever day was significantly higher in those with bacterial infection (n = 16) than in those without infection (n = 52). Similarly, among the 58 children in whom fever developed after day 5 postoperation, a significant difference was found in procalcitonin level at fever day between those with (n = 31) and without (n = 27) bacterial infection. CONCLUSION: During the critical early and late periods after cardiac surgery in children, procalcitonin level may help to differentiate patients with bacterial infection from patients in whom the fever is secondary to nonbacterial infectious causes.