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Fenómeno de Raynaud

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Fingers that go white, blue then red in the cold — primary vs secondary Raynaud's, keeping warm, and when it needs assessment.

Una mano abierta en la que las puntas de dos dedos aparecen blancas, una azul y la otra roja encendida: estas son las tres fases cromáticas de un ataque de Raynaud.
Durante un ataque de Raynaud, los dedos afectados se vuelven pálidos y fríos debido al cierre de los vasos sanguíneos pequeños; posteriormente adquieren un color azulado y luego rojizo a medida que la sangre vuelve a circular. Kieran Hirpara 4.0

Esta página se tradujo automáticamente y todavía no la ha revisado un médico. La versión en inglés es la versión oficial.

Qué está sintiendo

Sus dedos cambian de color y se sienten extraños cuando hace frío o cuando está estresado.
Un ataque típico consta de tres fases: primero los dedos se vuelven blancos, fríos y sin sensibilidad; luego se tornan azules a medida que la sangre se retira; finalmente adquieren un color rojo intenso y pueden palpitar o hormiguear cuando la sangre vuelve a circular. Durante este proceso, es posible notar entumecimiento, hormigueo o un dolor sordo. Lo mismo puede ocurrir a veces en los dedos de los pies, la nariz, las orejas o los labios.

Los ataques aparecen y desaparecen. Con frecuencia son desencadenados por algo sencillo (sacar alimentos del congelador, una mañana fría, sostener una bebida helada o una oleada repentina de estrés), y suelen remitir por sí solos una vez que el cuerpo se calienta, en un plazo de unos minutos a media hora. Entre un ataque y otro, los dedos suelen verse y sentirse completamente normales.

¿Qué está ocurriendo realmente?

Los pequeños vasos sanguíneos que irrigan los dedos están diseñados para estrecharse en el frío, con el fin de mantener la temperatura corporal. En el síndrome de Raynaud, esos vasos reaccionan de forma excesiva y se contraen mucho más de lo necesario. Esto se conoce como vasoespasmo. Durante un breve período, casi no llega sangre a la piel de los dedos: esa es la fase en la que los dedos se vuelven blancos, fríos y entumecidos. Cuando el espasmo cede, la sangre vuelve a circular y los dedos se ponen azules, luego rojos y nuevamente cálidos.

Es útil saber que existen dos tipos. El Raynaud primario es, con diferencia, el más común; básicamente se trata de una reacción excesiva del cuerpo al frío, sin que haya ninguna enfermedad subyacente. Suele aparecer en mujeres jóvenes, afecta a ambas manos de manera similar y es inofensivo, aunque puede resultar molesto. El Raynaud secundario es menos frecuente pero más importante, pues el vasoespasmo está relacionado con otra enfermedad, generalmente una que afecta al tejido conectivo, como la esclerodermia o el lupus. Las señales que indican la presencia del tipo secundario son: aparición de los síntomas en edades más avanzadas, afectación de una sola mano o de solo algunos dedos en lugar de ambas manos por igual, episodios muy graves, úlceras o llagas en las yemas de los dedos, o otros síntomas como dolor articular o erupciones cutáneas. Estas características justifican una evaluación médica adecuada.

Qué podemos hacer al respecto

Para la mayoría de las personas, la solución principal es sencilla y eficaz: mantenerse abrigado y evitar los desencadenantes.

  • Protéjase del frío. Use guantes (las manoplas mantienen los dedos juntos y más abrigados), utilice calentadores de manos y vístase en capas. Mantener todo el cuerpo y el torso abrigados es tan importante como cuidar las manos; los dedos permanecen relajados cuando el torso está caliente.
  • Evite el frío repentino. Use guantes al sacar algo del refrigerador o congelador, encienda el calefactor del coche con antelación y caliente las latas o botellas de bebidas frías en un portavasos aislante.
  • Deje de fumar. El tabaquismo estrecha los vasos sanguíneos y empeora el síndrome de Raynaud; dejar de fumar es una de las medidas más beneficiosas que puede tomar.
  • Limite el consumo de cafeína y de cualquier sustancia estimulante, pues ambas pueden desencadenar ataques. Controlar el estrés mediante cualquier método que le funcione también resulta útil, ya que el estrés por sí solo puede provocar vasoespasmo.

Si los ataques son frecuentes, dolorosos o graves, existen medicamentos que relajan los vasos sanguíneos y reducen su frecuencia. Los más comunes pertenecen al grupo de los bloqueadores de los canales de calcio (como el nifedipino); también hay otras opciones si estos no son adecuados para usted. Cuando el síndrome de Raynaud es secundario, tratar la enfermedad subyacente constituye una parte esencial del plan terapéutico; por eso, obtener un diagnóstico correcto es fundamental.

Qué esperar

En la gran mayoría de los casos (en quienes padecen Raynaud primario), se trata de una molestia manejable y no de un peligro real. Con medidas adecuadas de abrigo y evitando los desencadenantes, muchas personas logran reducir al mínimo los ataques y llevar una vida normal; los dedos se recuperan por completo tras cada episodio y no se producen daños duraderos. Suele ser una tendencia crónica que no desaparece, pero es muy controlable; además, existen medicamentos para cuando las medidas sencillas no resultan suficientes.

El Raynaud secundario requiere mayor atención, pues la enfermedad subyacente determina el curso del cuadro y, en algunos casos, la disminución del flujo sanguíneo puede dañar la piel de las yemas de los dedos. Precisamente por eso vale la pena determinar qué tipo de Raynaud se padece, a fin de recibir el nivel de cuidado adecuado según su situación particular.

¿Cuándo consultar a un especialista?

Acuda al médico para una evaluación si:

  • Sus episodios comenzaron en edad adulta, son graves o afectan una sola mano o solo algunos dedos, en lugar de ambas manos por igual: estos pueden ser signos del tipo secundario y, por lo general, requieren análisis de sangre y un examen de los pequeños vasos sanguíneos en la base de las uñas.
  • Le aparecen llagas, úlceras, grietas o deterioro de la piel en las yemas de los dedos, o una zona del dedo que permanece blanca, azulada, dolorosa o entumecida y no vuelve a calentarse: esto requiere atención inmediata.
  • Presenta otros síntomas además de los cambios de color: dolor o hinchazón articular, erupciones cutáneas, sequedad en los ojos o la boca, dificultad para tragar, o piel tensa o engrosada en los dedos.
  • Los episodios son frecuentes o tan dolorosos que interfieren con su vida diaria, a pesar de mantenerse abrigado y evitar los desencadenantes; en estos casos, los medicamentos pueden ser de ayuda.

En profundidad

Esta sección profundiza más de lo necesario para que usted tome decisiones sobre su propio tratamiento. El fenómeno de Raynaud merece ser leído con atención, ya que solo existe una clase de fármacos respaldada por buenas evidencias científicas; además, el tratamiento que actualmente despierta mayor interés actúa mediante un mecanismo inesperado.

Una clase de fármacos cuenta con evidencia científica

El síndrome de Raynaud consiste en espasmos episódicos de las arterias pequeñas de los dedos; por ello, el tratamiento busca mantener esos vasos sanguíneos abiertos. Se han probado numerosos vasodilatadores.

Un metaanálisis de 17 ensayos concluyó que los bloqueadores de los canales de calcio mostraron un beneficio estadísticamente significativo al reducir la frecuencia y gravedad de los síntomas, y que no existen pruebas que respalden el uso de otros agentes vasodilatadores orales aparte de los bloqueadores de los canales de calcio [1].

Esta segunda afirmación es la más útil: se trata de un hallazgo negativo respecto a toda una categoría de alternativas, y explica por qué el tratamiento suele iniciarse y mantenerse con una sola familia de fármacos, en lugar de probar varias opciones.

La toxina botulínica: por qué no produce el efecto que cabría esperar

La intervención que genera mayor interés en casos resistentes al tratamiento es la inyección de toxina botulínica alrededor de las arterias en la base de los dedos. Su uso en el fenómeno de Raynaud resistente al tratamiento médico ha arrojado resultados favorables, constituyendo una alternativa no invasiva a la cirugía cuya eficacia ha sido demostrada en estudios a pequeña escala [2].

Vale la pena comprender su mecanismo de acción, pues resulta contraintuitivo. La toxina botulínica es conocida por paralizar los músculos; por lo tanto, lo lógico sería pensar que relaja el músculo que forma la pared arterial. Sin embargo, la comprensión actual es distinta: interfiere con la señalización nerviosa simpática que induce la vasoconstricción, y parece actuar también sobre las vías del dolor; por eso, en algunos casos el alivio del dolor reportado supera con creces cualquier cambio en el flujo sanguíneo.

Cabe destacar el planteamiento honesto que se refleja en las propias evidencias: “estudios a pequeña escala”. Se trata de una opción prometedora para quienes ya han agotado todas las opciones de tratamiento médico, aunque aún no es una terapia consolidada.

La distinción que determina todo lo demás

La pregunta más importante es si el fenómeno es primario, es decir, que ocurre por sí solo, o si es secundario a una enfermedad subyacente, generalmente una enfermedad autoinmune del tejido conectivo como la esclerodermia o el lupus.

Esta diferencia no es meramente académica. El Raynaud primario resulta molesto pero tiene un pronóstico favorable y no provoca daño tisular. En cambio, el Raynaud secundario puede evolucionar hacia úlceras y pérdida de tejido en las yemas de los dedos; además, la enfermedad subyacente debe identificarse y tratarse por separado.

Los signos que generan preocupación son: aparición del cuadro después de los 30 años de edad, asimetría entre ambas manos, úlceras o cicatrices en las yemas de los dedos, y anomalías en los capilares de la unión ungueal. Estos indicadores requieren evaluación médica y no pueden ignorarse; por eso, ante un primer episodio de Raynaud, suele realizarse un estudio completo en lugar de limitarse a recomendar el uso de guantes.

Posición de la cirugía en el tratamiento

En casos de enfermedad secundaria grave con riesgo de daño tisular, la simpatectomía periarterial —que consiste en extirpar las fibras nerviosas simpáticas de la superficie de las arterias digitales— constituye la opción quirúrgica; actúa sobre la misma vía de señalización que la toxina botulínica, pero de forma permanente. Este procedimiento se reserva para casos de isquemia crítica y úlceras que no cicatrizan, y no para dedos fríos o incómodos; esto concuerda con la jerarquía de tratamientos mencionada anteriormente: cuanto más avanzado es el nivel de tratamiento, mayor es el objetivo de preservar el tejido en lugar de simplemente mejorar la comodidad del paciente.

Referencias

[1] Butendieck RR, Murray PM. Enfermedad de Raynaud. J Hand Surg Am. 2014;39(1):121-4. https://doi.org/10.1016/j.jhsa.2013.08.117

[2] Gallegos JE, Inglesby DC, Young ZT, Herrera FA. Toxina botulínica para el tratamiento del fenómeno de Raynaud refractario. J Hand Surg Am. 2021;46(1):54-9. https://doi.org/10.1016/j.jhsa.2020.07.009


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