Management of acute renal failure in the pediatric intensive care unit

Perioperative and long-term management of Fontan patients

A Fontan circulation requires a series of three-staged operations aimed to palliate patients with single-ventricle CHD. Currently, the most frequent technique is the extracardiac total cavopulmonary connection, an external conduit connecting the IVC and right pulmonary artery, bypassing the right side of the heart. Fontan candidates must meet strict criteria; they are assessed utilising both cardiac catheterisation and cardiac magnetic resonance. Postoperatively, treatment protocols prioritise antibiotic prophylaxis, diuretics, angiotensin-converting enzyme inhibitors, anticoagulation, and oxygen therapy with fluid restriction and a low-fat diet. These measures aim to reduce length of stay in the ICU and hospital by preventing acute complications such as infection, venous thromboembolism, low cardiac output, pleural effusion, and acute kidney injury. Late complications of a Fontan procedure include circulation failure, protein-losing enteropathy, plastic bronchitis, and Fontan-associated liver disease. The definitive management is cardiac transplantation, with promising innovations in selective embolisation of lymphatic vessels and Fontan-specific ventricular assist devices. Further research assessing current protocols in the perioperative management of Fontan patients would be beneficial for standardising current practice and improving outcomes.

Dexmedetomidine pretreatment attenuates myocardial ischemia reperfusion induced acute kidney injury and endoplasmic reticulum stress in human and rat

BACKGROUND

Patients undergoing cardiopulmonary bypass (CPB) often develop acute kidney injury (AKI) caused by myocardial ischemia reperfusion (MI/R), and this renal injury can be resolved notably by dexmedetomidine. Endoplasmic reticulum (ER) stress was reported to get involved in organ injury including AKI.

OBJECTIVES

The current study aimed to address the correlation between MI/R induced AKI with ER stress and to assess the effects of dexmedetomidine pretreatment on AKI protection.

METHOD

Patients selected for heart valve replacement surgery were randomly assigned to NS group (pre-anesthesia with 0.9% NaCl) and DEX group (pre-anesthesia with dexmedetomidine). Rat MI/R model was induced by occluding coronary artery for 30 min followed by 48-hour reperfusion. Rats were randomized into Sham (0.9% NaCl), I/R (MI/R + 0.9% NaCl) and I/R + DEX (MI/R + dexmedetomidine). Organ function and ER stress condition were evaluated by blood chemistry, pathology, and molecular test.

RESULTS

Clinical data indicated dexmedetomidine pretreatment attenuated AKI and oxidative stress as well as postischemic myocardial injury in patients. Accordingly animal results suggested dexmedetomidine reduced cellular injury and improved postischemic myocardial and renal function. Dexmedetomidine also reduced myocardial and renal cells apoptosis and down-regulated ER stress.

CONCLUSIONS

These results suggested that dexmedetomidine pretreatment attenuates MI/R injury-induced AKI by relieving the ER stress.

Acute kidney injury after pediatric cardiac surgery

Acute kidney injury is a common complication after pediatric cardiac surgery. The definition, staging, risk factors, biomarkers and management of acute kidney injury in children is detailed in the following review article.