Antonio R. Mott

A noninvasive estimation of mixed venous oxygen saturation using near-infrared spectroscopy by cerebral oximetry in pediatric cardiac surgery patients

Background : Near‐infrared spectroscopy (NIRS) is a noninvasive optical monitor of regional cerebral oxygen saturation (rSO2). The aim of this study was to validate the use of NIRS by cerebral oximetry in estimating invasively measured mixed venous oxygen saturation (SvO2) in pediatric postoperative cardiac surgery patients.

Worsening renal function in children hospitalized with decompensated heart failure: Evidence for a pediatric cardiorenal syndrome?*

Objectives: The purpose of this study was to determine the incidence of renal insufficiency in children hospitalized with acute decompensated heart failure and whether worsening renal function is associated with adverse cardiovascular outcome. Design: Prospective observational cohort study. Setting: Single-center childrens hospital. Patients: All pediatric patients from birth to age 21 yrs admitted to our institution with acute decompensated heart failure from October 2003 to October 2005. Interventions: None. Measurements and Main Results: Acute decompensated heart failure was defined as new-onset or acute exacerbation of heart failure signs or symptoms requiring hospitalization and inpatient treatment. We required that heart failure be attributable to ventricular dysfunction only. Worsening renal function was defined as an increase in serum creatinine by ≥0.3 mg/dL during hospitalization. Sixty-three patients (35 male, 28 female) comprised 73 patient hospitalizations. Median age at admission was 10 yrs (range 0.1–20.3 yrs). Median serum creatinine at admission was 0.6 mg/dL (range 0.2–3.5 mg/dL), and median creatinine clearance was 103 mL/min/1.73 m2 (range 22–431 mL/min/1.73 m2). Serum creatinine increased during 60 of 73 (82%) patient hospitalizations (median increase 0.2 mg/dL, range 0.1–2.7 mg/dL), and worsening renal function occurred in 35 of 73 (48%) patient hospitalizations. Clinical variables associated with worsening renal function included admission serum creatinine (p = .009) and blood urea nitrogen (p = .04) and, during hospitalization, continuous infusions of dopamine (p = .028) or nesiritide (p = .007). Worsening renal function was independently associated with the combined end point of in-hospital death or need for mechanical circulatory support (adjusted odds ratio 10.2; 95% confidence interval 1.7–61.2, p = .011). Worsening renal function was also associated with longer observed length of stay (33 ± 30 days vs. 18 ± 25 days, p < .03). Conclusions: These data suggest that an important cardiorenal interaction occurs in children hospitalized for acute decompensated heart failure. Renal function commonly worsens in such patients and is associated with prolonged hospitalization and in-hospital death or the need for mechanical circulatory assistance.

Mediastinitis after pediatric cardiac surgery: a 15-year experience at a single institution

BACKGROUND The spectrum of sternal wound infections after cardiac surgery ranges from superficial infections to a deep sternal infection known as mediastinitis. Mediastinitis is a rare but clinically relevant source of postoperative morbidity and mortality in adult and pediatric patients after cardiac surgery. METHODS We retrospectively identified all patients diagnosed with mediastinitis after cardiac surgery from January 1987 to December 2002 (17 patients/7,616 surgeries = 0.2%). Demographic data, cardiac diagnosis, cardiac surgery, hospital length of stay, associated medical diagnosis, and surgical treatment for mediastinitis were collected. RESULTS Fifteen pediatric patients (age < 18 years) were diagnosed with mediastinitis (mean age at diagnosis 37.5 months, range 21 days to 17 years. The median postoperative day of diagnosis was 14 days (6 to 50 days). The most common organism was Staphylococcus species (n = 9). Six patients had an associated bacteremia. The median hospital length of stay for all patients was 42.5 days (range 16 to 163 days). The hospital mortality was 1 of 15 (6%). Each patient was treated with intravenous antibiotics; sternal debridement; and rectus abdominus flap reconstruction (n = 7), pectoralis muscle flap reconstruction (n = 3), omentum reconstruction (n = 1), or primary sternal closure (n = 4). Three patients have undergone redo-sternotomy with orthotopic heart transplantation, bidirectional cavopulmonary anastomosis, and replacement of a right ventricle to pulmonary artery homograft. CONCLUSIONS Timely diagnosis, aggressive sternal debridement, and liberal use of rotational muscle flaps can potentially minimize the morbidity and mortality in pediatric postoperative cardiac patients. Subsequent redo-sternotomy has not been problematic.

The effect of short-term prophylactic methylprednisolone on the incidence and severity of postpericardiotomy syndrome in children undergoing cardiac surgery with cardiopulmonary bypass.

OBJECTIVE The aim of this study was to determine the effect of prophylactic immune suppression on the incidence and severity ofpostpericardiotomy syndrome (PPS) in children after cardiac surgery with cardiopulmonary bypass (CPB). BACKGROUND Prophylactic suppression of the inflammatory response has an unknown effect on the incidence and severity of PPS in children undergoing surgery with CPB. METHODS This randomized double-blind placebo controlled trial included two study groups. Group A received pre-CPB intravenous methylprednisolone (1 mg/kg) plus four additional intravenous doses over 24 h, and Group B received intravenous saline placebo at identical intervals. Data included patient demographics, cardiac diagnosis/operation, CPB time, incidence and severity of PPS. Noncomplicated PPS--temperature >100.5 degrees F, pericardial friction rub, patient irritability, small pericardial +/- pleural effusion. Complicated PPS--noncomplicated PPS plus hospital readmission +/- pericardiocentesis or thoracentesis. RESULTS We randomized 266 children: 20 exclusions (6 perioperative deaths, 14 reasons unrelated to treatment) leaving Group A (n = 126) and Group B (n = 120). There were no significant group differences in gender, cardiac diagnosis or CPB time. Group mean age differed (p = 0.05) and was treated as a covariate with no substantive outcome effect. In total, 39/246 children (16%) developed PPS (noncomplicated: n = 30, complicated: n = 9). There was no inter-group difference in overall PPS incidence (p = 0.73). However, Group A had a marginally significant increase in complicated PPS (p = 0.05). CONCLUSIONS Intravenous methylprednisolone at a standard anti-inflammatory dose administered pre-CPB and early post-CPB neither prevents nor attenuates PPS in children. Short-term pre-CPB and post-CPB methylprednisolone treatment may complicate PPS.

Triiodothyronine Supplementation in Infants and Children Undergoing Cardiopulmonary Bypass (TRICC) A Multicenter Placebo-Controlled Randomized Trial: Age Analysis

Background— Triiodothyronine levels decrease in infants and children after cardiopulmonary bypass. We tested the primary hypothesis that triiodothyronine (T3) repletion is safe in this population and produces improvements in postoperative clinical outcome. Methods and Results— The TRICC study was a prospective, multicenter, double-blind, randomized, placebo-controlled trial in children younger than 2 years old undergoing heart surgery with cardiopulmonary bypass. Enrollment was stratified by surgical diagnosis. Time to extubation (TTE) was the primary outcome. Patients received intravenous T3 as Triostat (n=98) or placebo (n=95), and data were analyzed using Cox proportional hazards. Overall, TTE was similar between groups. There were no differences in adverse event rates, including arrhythmia. Prespecified analyses showed a significant interaction between age and treatment (P=0.0012). For patients younger than 5 months, the hazard ratio (chance of extubation) for Triostat was 1.72. (P=0.0216). Placebo median TTE was 98 hours with 95% confidence interval (CI) of 71 to 142 compared to Triostat TTE at 55 hours with CI of 44 to 92. TTE shortening corresponded to a reduction in inotropic agent use and improvement in cardiac function. For children 5 months of age, or older, Triostat produced a significant delay in median TTE: 16 hours (CI, 7-22) for placebo and 20 hours (CI, 16-45) for Triostat and (hazard ratio, 0.60; P=0.0220). Conclusions— T3 supplementation is safe. Analyses using age stratification indicate that T3 supplementation provides clinical advantages in patients younger than 5 months and no benefit for those older than 5 months. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00027417.

Quantitative Echocardiographic Analysis of the Aortic Arch Predicts Outcome of Balloon Angioplasty of Native Coarctation of the Aorta

BACKGROUND The use of balloon angioplasty for treatment of native aortic coarctation is controversial. Cineangiographic data suggest that aortic arch hypoplasia and isthmic narrowing are associated with angioplasty failure. This study of echocardiographic measurements of preangioplasty aortic arch morphology was performed to identify potential anatomic predictors of outcome noninvasively. METHODS AND RESULTS The preangioplasty echocardiograms of 105 patients 3 days to 17 years old with native coarctation of the aorta were analyzed off-line. Angioplasty was considered successful if the residual coarctation gradient was < 20 mm Hg and no intervention for recoarctation occurred. Univariate analysis identified young age at angioplasty, presence of a patent ductus arteriosus, and the diameters of the aortic isthmus, distal transverse arch, and aortic valve as predictors of early and late outcomes. Multivariate analysis showed that the preangioplasty aortic isthmus z value was the best independent predictor of outcome, eliminating the effect on outcome of age and associated cardiac defects. An isthmus z value < or = -2.16 predicted early failure with 91% sensitivity and 85% specificity. Kaplan-Meier analysis demonstrated that 90% of patients with an isthmus z value > -1.0 remained free of recoarctation at late follow-up, whereas 89% of patients with a preangioplasty isthmus z value < or = -2.0 developed recoarctation within 36 months. CONCLUSIONS Echocardiographic measurements of the aortic arch predict both early and late outcomes of balloon angioplasty for native aortic coarctation, and the preangioplasty aortic isthmus z value was the best independent predictor. Quantitative aortic arch analysis may improve selection of angioplasty candidates who are likely to benefit from the procedure.

Safety of ketorolac in neonates and infants after cardiac surgery

Background:  Ketorolac is an injectable nonsteroidal anti‐inflammatory drug that is often used as a transitional short‐term analgesic to treat moderate pain and to decrease opioid use. There is a paucity of literature documenting the safety of using ketorolac in neonates and infants after cardiac surgery.

Glycemic profile in infants who have undergone the arterial switch operation: Hyperglycemia is not associated with adverse events

OBJECTIVE Tight glycemic control improves outcomes in critically ill adults. There are limited data regarding the effect of glycemic profiles in infants after cardiac operations. The aim of this study was to evaluate the association of hyperglycemia and hypoglycemia on adverse events in infants undergoing the arterial switch operation. METHODS From 2000 through 2005, 93 infants underwent the arterial switch operation (mean age, 2.5 +/- 5.9 weeks; mean weight, 3.4 +/- 0.8 kg). All serum glucose values during the first 24 postoperative hours were documented. The effect of time spent in specific glycemic bands on adverse events was determined. RESULTS Twenty-three (25%; group 1) infants spent more than 50% of the time with glucose values between 80 and 110 mg/dL, and 13 (14%; group 2) spent more than 50% of the time with glucose values of greater than 200 mg/dL. A total of 71 adverse events was documented in 45 (48%) of 93 infants. Group 1 infants were more likely to have any adverse event (P = .001) and renal insufficiency (P < .001). Group 2 infants were not more likely to have adverse events. When controlling for preoperative and operative factors, being in group 1 was an independent predictor of postoperative adverse events (P = .004). CONCLUSION Hyperglycemia does not appear to be detrimental in postoperative infants with congenital heart disease. Infants who spent the majority of the time with glucose values between 80 and 110 mg/dL were at increased risk for adverse events. The ideal glycemic profile in the postoperative cardiac infant has yet to be defined.

Renal effects of fenoldopam in critically ill pediatric patients: A retrospective review.

Objective: Published data describe the use of fenoldopam in adults for treatment of oliguria/anuria and for renal perfusion and protection, but pediatric data are scant. We assessed the effects of fenoldopam on urine output and potential deleterious changes in hemodynamics or serum creatinine in children. Design: Retrospective analysis. Setting: Academic institution. Patients: All patients ≤18 yrs old at our institution who received ≥24 hrs of fenoldopam therapy. Exclusion criteria included mechanical circulatory support, initiation of fenoldopam in the operating room, and age >18 yrs. Interventions: None. Measurements and Main Results: Demographics, renal function, fenoldopam dosing, concomitant inotropes, and inotrope score data were collected and analyzed. Thirteen patients (age 0.3–18.7 yrs, median 5.5 yrs) received a mean infusion dose of 0.07 ± 0.08 &mgr;g/kg/min (range 0.01–0.26 &mgr;g/kg/min) over the first 24 hrs of therapy. Eight patients received fenoldopam to augment urine output, and five patients received fenoldopam to increase renal perfusion. Nine (69%) patients received dopamine concurrently. Mean inotrope score at the beginning of therapy was 11.3 ± 7.6 and did not change during therapy. Mean urine output increased from 1.82 ± 1.5 mL/kg/hr to 2.74 ± 1.4 mL/kg/hr (p = .009) in the first 24 hrs of fenoldopam therapy. No change in serum creatinine occurred (p not significant). Blood urea nitrogen was significantly different from baseline (41.7 ± 18.7 vs. 49.0 ± 19.8 mg/dL, p = .02). Patients with lower baseline urine output had a greater increase in urine output with fenoldopam. One patient experienced clinically significant hypotension while receiving fenoldopam, which was thought to be due to a concurrent nitroprusside infusion. Conclusions: Fenoldopam increases urine output in select critically ill pediatric patients without requiring escalation of inotropic support. There were no adverse hemodynamic effects or alterations in serum creatinine. Further prospective pediatric studies to define the role of fenoldopam in children are warranted.

Safety and efficacy of intravenous labetalol for hypertensive crisis in infants and small children.

Objective: To determine the efficacy and safety of labetalol for hypertensive crisis in children ≤24 months of age. Design: Retrospective chart review. Statistical analysis utilized analysis of variance for continuous data, chi-square tests for nominal data, and linear regression. Setting: A 737-bed pediatric teaching institution. Patients: Twenty-seven patients ≤24 months of age were treated with 37 intravenous infusions of labetalol, nicardipine, or nitroprusside for hypertensive crisis or hypertensive urgency. Interventions: None. Measurements and Main Results: The primary end point consisted of time to 20% reduction in systolic blood pressure. Primary safety end points measured the prevalence of deleterious effects of labetalol. Continuous infusion of labetalol reduced mean systolic blood pressure by at least 20% in <8 hrs. This effect was similar to nicardipine and nitroprusside infusions. The reported side effects were similar in each group. Patients receiving labetalol and presenting with ischemic or traumatic brain injury were likely to develop hypotension requiring infusion discontinuation. Conclusions: Continuous intravenous labetalol infusion is efficacious for treatment of hypertensive crisis in children ≤24 months of age. Aside from patients presenting with ischemic or traumatic brain injury, labetalol was safe to use in this population for hypertensive emergencies and had a satisfactory adverse effect profile. Labetalol may reach dose saturation at a much lower dose in young children in comparison to adults. Clinicians should use caution when initiating labetalol infusions in young patients with brain injury.