RESUMO
BACKGROUND: Post-operative hypoparathyroidism is the most frequent complication after total thyroidectomy. It represents one of the main causes of prolonged hospital-stay and is associated with a significant increase in health costs. The identification of patients with higher risk of suffering this complication allows early treatment, reduces clinical complications and adequate the use of health resources. Throughout history, several predictors have been used to stratify patients at risk. In recent years the use of parathormone parathyroid hormone (PTH) has taken particular interest. OBJECTIVE: To review the existing literature on the use of PTH as a predictor of hypocalcemia after thyroidectomy. METHOD: A medline search was performed. We reviewed the existing evidence on efficacy of PTH as a predictor of post-operative hypocalcemia, economic impact, optimal time for sampling and implementation mode. CONCLUSION: The use of PTH predicts with adequate sensitivity, specificity, negative and positive predictive value the risk for the patients to suffer post-operative hypocalcemia. Cut-off values and sampling number and time vary among authors; as a result, more data is needed to reach a conclusion about the standardization of use after a total thyroidectomy procedure. It use could be beneficial not only for patients but also for care providers as health cost might be diminished.
ANTECEDENTES: El hipoparatiroidismo posoperatorio constituye la complicación más frecuente de la tiroidectomía total. Se asocia, entre otras cosas, a internación prolongada y múltiples pruebas de laboratorio, y con ello a un incremento en los costos de salud. La identificación de pacientes con mayor riesgo de padecer esta complicación permite realizar un tratamiento precoz, disminuyendo el costo económico y evitando complicaciones asociadas a un retraso en la externación. Se han descrito diversos predictores para identificar tempranamente a los pacientes en riesgo; en los últimos años, ha tomado particular relevancia el uso de la parathormona (PTH). OBJETIVO: El objetivo del presente trabajo es revisar la literatura existente sobre la utilidad de la PTH como predictor de hipocalcemia postiroidectomía. MÉTODO: Se realizó una búsqueda en PubMed revisando la evidencia existente sobre eficacia de la PTH como predictor de hipocalcemia posoperatoria, su repercusión económica, el tiempo óptimo para la toma de muestra y el modo de implementación. CONCLUSIÓN: El uso de la PTH permite predecir con adecuada sensibilidad, especificidad, valor predictivo negativo y valor predictivo positivo los pacientes en riesgo de padecer hipocalcemia posoperatoria. Sin embargo, los valores de corte, los tiempos de toma de muestra y la cantidad de estas varían entre los autores, por lo que persisten algunos interrogantes acerca de la estandarización de su uso.
Assuntos
Hipocalcemia/etiologia , Hipoparatireoidismo/etiologia , Hormônio Paratireóideo/sangue , Complicações Pós-Operatórias/etiologia , Tireoidectomia/efeitos adversos , Biomarcadores/sangue , Cálcio/sangue , Cálcio/economia , Humanos , Hipocalcemia/sangue , Hipocalcemia/economia , Hipoparatireoidismo/sangue , Hormônio Paratireóideo/economia , Complicações Pós-Operatórias/sangue , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Fatores de TempoRESUMO
BACKGROUND: Symptomatic hypocalcemia is a common complication of total thyroidectomy. Management strategies include responsive treatment initiation for symptoms or prevention by routine or parathyroid hormone-directed calcium supplementation. The comparative cost-effectiveness of even the most often utilized strategies is unclear. METHODS: A Markov cohort model was created to compare routine supplementation with calcium alone (RS), postoperative parathyroid hormone-based selective supplementation with calcium and calcitriol (SS), and no supplementation (NS) in asymptomatic patients. Patients could remain asymptomatic or develop symptomatic hypocalcemia, managed with outpatient oral supplementation or intravenous calcium infusion and administered either inpatient or outpatient. Effectiveness was measured in quality-adjusted life years. Sensitivity analyses were performed to test model parameter assumptions. RESULTS: RS was the preferred strategy, costing $329/patient and resulting in 0.497 quality-adjusted life years, which was only marginally better compared to SS ($373 for 0.495 quality-adjusted life years). NS was most costly at $4,955 for 0.491 quality-adjusted life years. Preference for RS over SS was sensitive to the probability of developing symptoms and the probability of symptom treatment with intravenous supplementation. On probabilistic sensitivity analysis, RS was preferred in 75.4% of scenarios. CONCLUSION: After total thyroidectomy, a preventative calcium supplementation strategy should be strongly considered. In this data-driven theoretical model, RS was the least costly option and resulted in an incremental gain in quality-adjusted life years.