Extent, Risk Factors, and Outcome of Fluid Overload After Pediatric Heart Surgery

• Published in: Critical care medicine Vol. 42; no. 12; pp. 2591 - 2599
• Main Authors: Seguin, Jade, Albright, Benjamin, Vertullo, Laura, Lai, Pamela, Dancea, Adrian, Bernier, Pierre-Luc, Tchervenkov, Christo I, Calaritis, Christos, Drullinsky, David, Gottesman, Ronald, Zappitelli, Michael
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD by the Society of Critical Care Medicine and Lippincott Williams & Wilkins 01-12-2014; Lippincott Williams & Wilkins
• Subjects: Acute Kidney Injury - epidemiology; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Body Fluids - metabolism; Cardiac Surgical Procedures - adverse effects; Cardiac Surgical Procedures - mortality; Child; Child, Preschool; Emergency and intensive postoperative care (general aspects). Pathophysiology of surgery; Female; Humans; Incidence; Infant; Intensive care medicine; Intensive Care Units, Pediatric - statistics & numerical data; Kidneys; Length of Stay - statistics & numerical data; Male; Medical sciences; Nephrology. Urinary tract diseases; Postoperative Complications - epidemiology; Postoperative Complications - mortality; Respiration, Artificial - statistics & numerical data; Retrospective Studies; Risk Factors; Sex Factors; Urinary system involvement in other diseases. Miscellaneous; Human; Kidney disease; Edema; Pediatrics; Intensive care; Urinary system disease; Prognosis; Acute kidney injury; fluid therapy; Infant; Cardiac surgery; Treatment; Risk factor; Evolution; pediatric intensive care units; Hyperhydration; Child; Mechanical ventilation; Resuscitation
• ISSN: 0090-3493; 1530-0293
• DOI: 10.1097/CCM.0000000000000517

OBJECTIVES:Fluid overload is associated with poor PICU outcomes in different populations. Little is known about fluid overload in children undergoing cardiac surgery. We described fluid overload after cardiac surgery, identified risk factors of worse fluid overload and also determined if fluid overload predicts longer length of PICU stay, prolonged mechanical ventilation (length of ventilation) and worse lung function as estimated by the oxygenation index.
DESIGN:Retrospective cohort study.
SETTING:Montreal Childrenʼs Hospital PICU, Montreal, Canada.
PATIENTS:Patients 18 years or younger undergoing cardiac surgery (2005–2007).
INTERVENTIONS:None.
MEASUREMENTS AND MAIN RESULTS:Cumulative fluid overload % was calculated as [(total fluid in – out in L)/admission weight (kg) × 100] and expressed as PICU peak cumulative fluid overload % throughout admission and PICU day 2 cumulative fluid overload %. Primary outcomes were length of stay and length of ventilation. The secondary outcome was oxygenation index. Fluid overload risk factors were evaluated using stepwise linear regression. Fluid overload-outcome relations were evaluated using stepwise Cox regression (length of stay, length of ventilation) and generalized estimating equations (daily PICU cumulative fluid overload % and oxygenation index repeated measures). There were 193 eligible surgeries. Peak cumulative fluid overload % was 7.4% ± 11.2%. Fluid overload peaked on PICU day 2. Lack of past cardiac surgery (p = 0.04), cyanotic heart disease (p = 0.03), and early postoperative fluids (p = 0.0001) was independently associated with higher day 2 fluid overload %. Day 2 fluid overload % predicted longer length of stay (adjusted hazard ratio, 0.95; 95% CI, 0.92–0.99; p = 0.009) and length of ventilation (adjusted hazard ratio, 0.97; 95% CI, 0.94–0.99; p = 0.03). In patients without cyanotic heart disease, worse daily fluid overload % predicted worse daily oxygenation index.
CONCLUSION:Fluid overload occurs early after cardiac surgery and is associated with prolonged PICU length of stay and ventilation. Future fluid overload avoidance trials may confirm or refute a true fluid overload-outcome causative association.