Perioperative administration of angiotensin converting enzyme inhibitors decreases the severity and duration of pleural effusions following bidirectional cavopulmonary anastomosis

Hypoplastic left heart syndrome: current considerations and expectations

In the recent era, no congenital heart defect has undergone a more dramatic change in diagnostic approach, management, and outcomes than hypoplastic left heart syndrome (HLHS). During this time, survival to the age of 5 years (including Fontan) has ranged from 50% to 69%, but current expectations are that 70% of newborns born today with HLHS may reach adulthood. Although the 3-stage treatment approach to HLHS is now well founded, there is significant variation among centers. In this white paper, we present the current state of the art in our understanding and treatment of HLHS during the stages of care: 1) pre-Stage I: fetal and neonatal assessment and management; 2) Stage I: perioperative care, interstage monitoring, and management strategies; 3) Stage II: surgeries; 4) Stage III: Fontan surgery; and 5) long-term follow-up. Issues surrounding the genetics of HLHS, developmental outcomes, and quality of life are addressed in addition to the many other considerations for caring for this group of complex patients.

Risk factors for postoperative acute kidney injury in pediatric cardiac surgery patients receiving angiotensin-converting enzyme inhibitors

BACKGROUND

Angiotensin-converting enzyme inhibitor therapy is often initiated in pediatric patients who have had cardiac surgery. Acute kidney injury can occur in patients secondary to angiotensin-converting enzyme inhibitor initiation. Risk factors for acute kidney injury after angiotensin-converting enzyme inhibitor initiation have yet to be defined in postoperative pediatric cardiac patients.

OBJECTIVES

To identify the frequency of acute kidney injury in patients receiving angiotensin-converting enzyme inhibitor therapy in postoperative pediatric cardiac surgical patients and to identify risk factors for acute kidney injury in this patient population.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The pharmacy and surgery databases were used to identify all patients <18 yrs of age who received angiotensin-converting enzyme inhibitor therapy after cardiac surgery at our institution from January 2006 to December 2007. Patients who did not have a baseline serum creatinine and at least one serum creatinine obtained after angiotensin-converting enzyme inhibitor initiation were excluded. Data collection included demographic information and cardiac pathophysiology/surgery, diuretic and/or nephrotoxic medication use, and angiotensin-converting enzyme inhibitor characteristics and initiation date. Baseline, daily, and maximum serum creatinine values were collected. Acute kidney injury was defined as the maximum change in pediatric-modified RIFLE (Risk, Injury, Failure, Loss, End-stage) acute kidney injury criteria within 48 hrs of initiation or increase in dose of angiotensin-converting enzyme inhibitor. Descriptive statistics were used to characterize the patient population, and a multivariate logistic regression model was developed to identify independent predictors of angiotensin-converting enzyme inhibitor-associated acute kidney injury. The study included 415 patient admissions (386 patients), 57% (n = 239) being male and infants (31 days to 2 yrs) being the most common age group. A functional single ventricle was present in 46% of the patients. Enalapril was initiated in 60% (n = 250) and captopril in 40% (n = 165) of patient admissions. Acute kidney injury occurred in 21% (n = 88) of patients initiated on an angiotensin-converting enzyme inhibitor (pediatric-modified RIFLE categories: R = 15%, I = 3%, F = 4%). Logistic regression identified cyanosis, coadministration of furosemide, and baseline estimated creatinine clearance as independent risk factors for any degree of angiotensin-converting enzyme inhibitor-associated acute kidney injury (p < .05). The hospital lengths of stay of patients with angiotensin-converting enzyme inhibitor-associated acute kidney injury (median 12 days, range 4-298 days) were greater compared to those of patients without angiotensin-converting enzyme inhibitor-associated acute kidney injury (median 10 days, range 3-199 days, p < .05).

CONCLUSIONS

Initiation of angiotensin-converting enzyme inhibitor after cardiac surgery in pediatric patients may result in acute kidney injury. The presence of cyanosis and coadministration of furosemide are independent risk factors for acute kidney injury in patients receiving angiotensin-converting enzyme inhibitor.

Risk factors for persistent pleural effusions after the extracardiac Fontan procedure

OBJECTIVE

Pleural effusions after the Fontan operation contribute significantly to morbidity and prolonged hospitalization. This study investigates the association between selected preoperative, operative, and postoperative variables and persistent pleural effusions after the extracardiac Fontan procedure.

METHODS

We conducted a retrospective study of extracardiac Fontan procedures. The variables analyzed as potential risk factors included age and weight at the time of the operation, anatomic diagnosis, preoperative oxygen saturation, mean pulmonary artery pressure, ventricular end-diastolic pressure, presence of an accessory source of pulmonary blood flow, presence of significant aortopulmonary collateral vessels, presence of fenestration, cardiopulmonary bypass time, conduit size, postoperative pulmonary artery pressure, use of angiotensin-converting enzyme inhibitors, and presence of postoperative infection. The outcome measures evaluated were duration and volume of chest tube drainage after surgical intervention.

RESULTS

From June 1997 to August 2002, 100 consecutive patients underwent the extracardiac Fontan procedure. The median age at operation was 3.1 years. The median duration of chest tube drainage was 10 days, and the median volume of drainage was 14.7 mL.kg(-1).d(-1). As determined by means of multivariate analysis, significant risk factors for pleural effusions lasting more than 2 weeks were lower preoperative oxygen saturation (P =.011) and the presence of postoperative infections (P =.003). Significant risk factors for pleural effusions draining at more than 20 mL.kg(-1).d(-1) were lower preoperative oxygen saturation (P =.005), smaller conduit size (P =.04), and longer duration of cardiopulmonary bypass (P =.004).

CONCLUSIONS

Lower preoperative oxygen saturation, presence of postoperative infection, smaller conduit size, and longer duration of cardiopulmonary bypass were associated with persistent pleural effusions after the extracardiac Fontan procedure. Modifications of some of these risk factors might influence the duration and volume of pleural drainage after surgical intervention.