SERUM ELECTROLYTES AND OUTCOME IN PATIENTS UNDERGOING ENDOSCOPIC GASTROSTOMY.

BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) is a gold standard for long term enteral feeding. Neurologic dysphagia and head/neck cancer are the most common indications for PEG as they can lead to protein-energy malnutrition and serum electrolyte abnormalities, with potential negative impact on metabolic balance. Refeeding syndrome may also be related with severe electrolyte changes in PEG-fed patients and contribute to poor prognosis. OBJECTIVE: This study aims to evaluate the changes in serum concentrations of the main electrolytes and its possible association with the outcome. METHODS: Retrospective study of patients followed in our Artificial Nutrition Clinic, submitted to PEG from 2010 to 2016, having head/neck cancer or neurologic dysphagia, who died under PEG feeding. Serum electrolytes (sodium, potassium, chlorine, magnesium, calcium and phosphorus) were evaluated immediately before the gastrostomy procedure. Survival after PEG until death was recorded in months. RESULTS: We evaluated 101 patients, 59 with electrolyte alterations at the moment of the gastrostomy. Sodium was altered in 32 (31.7%), magnesium in 21 (20.8%), chlorine in 21 (20.8%), potassium in 14 (13.8%), calcium in 11 (10.9 %) and phosphorus in 11 (10.9%). The survival of patients with low sodium (<135 mmol/L) was significantly lower when compared to patients with normal/high values, 2.76 months vs 7.80 months, respectively (P=0.007). CONCLUSION: Changes in serum electrolytes of patients undergoing PEG were very common. More than half showed at least one abnormality, at the time of the procedure. The most frequent was hyponatremia, which was associated with significantly shorter survival, probably reflecting severe systemic metabolic distress.

Eletrólitos séricos e prognóstico em doentes submetidos a gastrostomia endoscópica / Serum electrolytes and outcome in patients undergoing endoscopic gastrostomy

ABSTRACT BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) is a gold standard for long term enteral feeding. Neurologic dysphagia and head/neck cancer are the most common indications for PEG as they can lead to protein-energy malnutrition and serum electrolyte abnormalities, with potential negative impact on metabolic balance. Refeeding syndrome may also be related with severe electrolyte changes in PEG-fed patients and contribute to poor prognosis. OBJECTIVE: This study aims to evaluate the changes in serum concentrations of the main electrolytes and its possible association with the outcome. METHODS: Retrospective study of patients followed in our Artificial Nutrition Clinic, submitted to PEG from 2010 to 2016, having head/neck cancer or neurologic dysphagia, who died under PEG feeding. Serum electrolytes (sodium, potassium, chlorine, magnesium, calcium and phosphorus) were evaluated immediately before the gastrostomy procedure. Survival after PEG until death was recorded in months. RESULTS: We evaluated 101 patients, 59 with electrolyte alterations at the moment of the gastrostomy. Sodium was altered in 32 (31.7%), magnesium in 21 (20.8%), chlorine in 21 (20.8%), potassium in 14 (13.8%), calcium in 11 (10.9 %) and phosphorus in 11 (10.9%). The survival of patients with low sodium (<135 mmol/L) was significantly lower when compared to patients with normal/high values, 2.76 months vs 7.80 months, respectively (P=0.007). CONCLUSION: Changes in serum electrolytes of patients undergoing PEG were very common. More than half showed at least one abnormality, at the time of the procedure. The most frequent was hyponatremia, which was associated with significantly shorter survival, probably reflecting severe systemic metabolic distress.

RESUMO CONTEXTO: A gastrostomia endoscópica percutânea (PEG) é a via de eleição preferencial para a nutrição entérica de longa duração. A disfagia neurológica e as neoplasias cervico-faciais constituem as principais indicações para PEG por poderem conduzir a desnutrição energético-proteica e alterações hidroeletrolíticas, com potencial impacto negativo no equilíbrio metabólico. A síndrome de realimentação pode também estar associada a alterações hidroeletrolíticas graves em doentes alimentados por PEG e contribuir para um mau prognóstico. OBJETIVO: Avaliar as alterações das concentrações séricas dos principais eletrólitos e a eventual associação entre os valores séricos alterados e o prognóstico dos doentes gastrostomizados. Métodos - Estudo retrospetivo realizado em doentes seguidos na Consulta de Nutrição Artificial do Hospital Garcia de Orta, propostos e submetidos a PEG, de 2010 a 2016 e que faleceram sob nutrição por PEG. Consideraram-se os valores séricos dos iões em estudo avaliados imediatamente antes do procedimento endoscópico de gastrostomia, obtidos por consulta do processo clínico. A sobrevida, após a realização da PEG até à morte foi registrada em meses. RESULTADOS: Avaliaram-se 101 doentes. A sobrevida média pós-gastrostomia foi 6,55 meses. Destes, 59 apresentaram alterações de alguns iões no momento da realização da PEG. O sódio estava alterado em 31 (30,6%), magnésio em 20 (19,8%), cloro em 19 (18,8%), potássio em 14 (13,8%), cálcio em 10 (9,9%) e o fósforo em 9 (8,9%). Quando comparada a sobrevida dos doentes com valores de sódio baixo (<135 mmol/L) com a dos doentes com valores normais/elevados, esta foi 2,76 meses vs 7,80 meses, respectivamente (P=0,007). CONCLUSÃO: As alterações dos eletrólitos séricos nos doentes submetidos a PEG foram muito frequentes, com mais de metade dos doentes a apresentarem pelo menos uma alteração aquando da realização do procedimento. A alteração mais frequente foi a hiponatrémia, associando-se a pior prognóstico com sobrevida significativamente mais curta, refletindo provavelmente um grave compromisso metabólico sistêmico.