Jesus Lopez-Herce, Hospital General Universitario Gregorio Marañón. Madrid. Spain
16 June 2010
Complications in children on CRRT Maria José Santiago, Jesús López-Herce
Dear Sir We have read with interest Dra Palmieri comments (1) on our article “Complications of continuous renal replacement therapy in critically ill children: a prospective observational evaluation study” (2) and we would like to add some considerations: We agree with Dra Palmieri that our study has certain limitations. Although the total number of patients studied was large for CRRT in children in a single-centre study, which ensures greater homogeneity in treatment and data collection, it still must be determined whether our results can be extrapolated to other PICU. On the other hand, the duration of the study was long and the improvements in other treatments in critically ill patients could have affected the results. There is a north American registry that has published the demographic characteristics of pediatric continuous renal replacement therapy (3). However, in this registry the complications associated with CRRT have not been assessed. We agree with Dra Palmieri that a multicentric and multinationality study is necessary to assess the efficacy and complications of CRRT in children. With regard to the CRRT security, controlled studies must be performed to analyse several questions such as what the best vascular access is, what the most appropriate membrane type and surface is depending on the weight and age of the patients, and what the most appropriate method to avoid the premature coagulation in filters is (4). Regarding the risk of hypotension at the time of connection, the importance of designing controlled studies to compare the efficacy and security of circuit-priming methods in the reduction of hypotension at the time of connection is superlative. On the other hand, Palmieri comments that an isolated electrolyte abnormality does not necessarily constitute a clinically significant complication. This affirmattion is evident. However it is also evident that fast electrolyte abnormality detection and correction is essential to avoid clinically significant complications. Our study shows the changes in electrolytes concentrations produced in children on CRRT despite using balanced dialysis and replacement solutions. The evolution and abnormalities of electrolytes in children on CRRT have not been previously described. Not always but sometimes abnormalities in the electrolytes are due to the technique or the fluids used, for instance, hypophosphatemia is directly associated to the technique (5). We think that our results could lead to a change in the concentrations of sodium, chloride and the addition of phosphate in the standard dialysis and replacement fluids used in CRRT (2).
1. Palmieri TL. Complications of continuous renal replacement therapy in children. Are all created equal? Crit Care 2010;14:105. 2. Santiago MJ, López-Herce J, Urbano J, Solana MJ, del Castillo J, Ballestero Y, Botrán M, Bellón JM. Complications of continuous renal replacement therapy in critically ill children: a prospective observational evaluation study.Crit Care. 2009;13:R184. 3. Symons JM, Chua AN, Somers MJ, Baum MA, Bunchman TE, Benfield MR, Brophy PD, Blowey D, Fortenberry JD, Chand D, Flores FX, Hackbarth R, Alexander SR, Mahan J, McBryde KD, Goldstein SL. Demographic characteristics of pediatric continuous renal replacement therapy: a report of the prospective pediatric continuous renal replacement therapy registry. Clin J Am Soc Nephrol 2007. 2: 732-738. 4. Del Castillo J, López-Herce J, Cidoncha E, Urbano J, Mencía S, Santiago MJ, Bellón JM. Circuit life span in critically ill children on continuous renal replacement treatment: a prospective observational evaluation study. Crit Care. 2008;12:R93. 5. Santiago MJ, López-Herce J, Urbano J, Bellón JM, del Castillo J, Carrillo A: Hypophosphatemia and phosphate supplementation during continuous renal replacement therapy in children. Kidney Int 2009, 75:312-316.
Critical Care
Complications in children on CRRT
16 June 2010
Complications in children on CRRT
Maria José Santiago, Jesús López-Herce
Dear Sir
We have read with interest Dra Palmieri comments (1) on our article “Complications of continuous renal replacement therapy in critically ill children: a prospective observational evaluation study” (2) and we would like to add some considerations:
We agree with Dra Palmieri that our study has certain limitations. Although the total number of patients studied was large for CRRT in children in a single-centre study, which ensures greater homogeneity in treatment and data collection, it still must be determined whether our results can be extrapolated to other PICU. On the other hand, the duration of the study was long and the improvements in other treatments in critically ill patients could have affected the results.
There is a north American registry that has published the demographic characteristics of pediatric continuous renal replacement therapy (3). However, in this registry the complications associated with CRRT have not been assessed. We agree with Dra Palmieri that a multicentric and multinationality study is necessary to assess the efficacy and complications of CRRT in children.
With regard to the CRRT security, controlled studies must be performed to analyse several questions such as what the best vascular access is, what the most appropriate membrane type and surface is depending on the weight and age of the patients, and what the most appropriate method to avoid the premature coagulation in filters is (4). Regarding the risk of hypotension at the time of connection, the importance of designing controlled studies to compare the efficacy and security of circuit-priming methods in the reduction of hypotension at the time of connection is superlative.
On the other hand, Palmieri comments that an isolated electrolyte abnormality does not necessarily constitute a clinically significant complication. This affirmattion is evident. However it is also evident that fast electrolyte abnormality detection and correction is essential to avoid clinically significant complications. Our study shows the changes in electrolytes concentrations produced in children on CRRT despite using balanced dialysis and replacement solutions. The evolution and abnormalities of electrolytes in children on CRRT have not been previously described. Not always but sometimes abnormalities in the electrolytes are due to the technique or the fluids used, for instance, hypophosphatemia is directly associated to the technique (5). We think that our results could lead to a change in the concentrations of sodium, chloride and the addition of phosphate in the standard dialysis and replacement fluids used in CRRT (2).
1. Palmieri TL. Complications of continuous renal replacement therapy in children. Are all created equal? Crit Care 2010;14:105.
2. Santiago MJ, López-Herce J, Urbano J, Solana MJ, del Castillo J, Ballestero Y, Botrán M, Bellón JM. Complications of continuous renal replacement therapy in critically ill children: a prospective observational evaluation study.Crit Care. 2009;13:R184.
3. Symons JM, Chua AN, Somers MJ, Baum MA, Bunchman TE, Benfield MR, Brophy PD, Blowey D, Fortenberry JD, Chand D, Flores FX, Hackbarth R, Alexander SR, Mahan J, McBryde KD, Goldstein SL. Demographic characteristics of pediatric continuous renal replacement therapy: a report of the prospective pediatric continuous renal replacement therapy registry. Clin J Am Soc Nephrol 2007. 2: 732-738.
4. Del Castillo J, López-Herce J, Cidoncha E, Urbano J, Mencía S, Santiago MJ, Bellón JM. Circuit life span in critically ill children on continuous renal replacement treatment: a prospective observational evaluation study. Crit Care. 2008;12:R93.
5. Santiago MJ, López-Herce J, Urbano J, Bellón JM, del Castillo J, Carrillo A: Hypophosphatemia and phosphate supplementation during continuous renal replacement therapy in children. Kidney Int 2009, 75:312-316.
Competing interests
Authors declare no competing interest