Estreñimiento en adultos

Para niños, consulte el apartado separado Estreñimiento en niños artículo.

Estreñimiento en adultos

Chronic constipation is common with a reported prevalence of 12-15% worldwide.¹²Different studies suggest that it is more common in the US and Europe than Asia²and conversely that it is more common in Asia and the Americas than in Europe.¹ There is a higher prevalence in women and it increases in prevalence with age.¹Non-white people report constipation more frequently than white people.¹ It is also more common in those of lower socio-economic status, residents of nursing homes and those with other medical conditions.³

What is constipation?⁴

Constipation is a symptom not a diagnosis and means different things to different people.

There is an internationally recognised medical definition of constipation which has been updated over the last few decades and, at the time of writing, involves the Rome IV criteria.

These state that a patient must have experienced at least two of the following symptoms over the preceding 3 months:⁵

• Fewer than three spontaneous bowel movements per week.

• Straining for more than 25% of defecation attempts.

• Lumpy or hard stools for at least 25% of defecation attempts.

• Sensation of anorectal obstruction or blockage for at least 25% of defecation attempts.

• Sensation of incomplete defecation for at least 25% of defecation attempts.

• Manual manoeuvring required to defecate for at least 25% of defecation attempts.

The Rome IV criteria also stipulate that a patient should not meet the suggested criteria for síndrome del intestino irritable (SII) and that loose stools are rarely present without the use of laxatives.

However, patients' use of the word may involve various symptoms and it is essential to ask patients exactly what they mean by the term constipation.

Los pacientes pueden significar que:

• Las heces son demasiado duras.

• No defecan con la frecuencia suficiente para una 'limpieza interna'.

• Defecar duele.

• Tienen diarrea.

En los ancianos, considere el estreñimiento en cualquier paciente que presente:

• Confusión o delirio, deterioro funcional.

• Náuseas o pérdida de apetito.

• Diarrea por desbordamiento.

• Retención urinaria.

Se debe sospechar de carga fecal o impactación cuando hay antecedentes de:

• Heces duras y grumosas, que pueden ser grandes e infrecuentes (por ejemplo, evacuadas cada 7-10 días), o pequeñas y relativamente frecuentes (por ejemplo, evacuadas cada 2-3 días).

• Una necesidad de utilizar métodos manuales de extracción fecal.

• Overflow faecal incontinence, loose stool, excessive wiping, or regularly soiled underwear.

Causas del estreñimiento en adultos

Taking a careful history helps to determine the possible cause.

Historia clínica:

• Always consider the possibility of a serious underlying cause. Particularly enquire whether there are associated 'red flags' such as weight loss or rectal bleeding.

• Frequency, nature, and consistency of the stool.

• Whether there is blood or mucus in/on the stools.

• Whether there is diarrhoea alternating with constipation.

• Whether there has been a recent change in bowel habit.

• Any accompanying symptoms such as fever, vomiting, or loss of appetite.

• Any family history of inflammatory bowel disease or bowel cancer.

• Assessment of any risk factors such as:

  • Fibra dietética o líquidos inadecuados.

  • Falta de ejercicio.

  • Toileting habits that might predispose to constipation - eg, feeling hurried or being disturbed when trying to defecate, withholding or ignoring the urge to defecate, access to the toilet at home or work, and level of privacy.

  • Ansiedad, depresión, deterioro cognitivo o un trastorno alimenticio.

  • Drug treatment or clinical features that might suggest an underlying organic cause of secondary constipation.

Examination:

Siempre realice un examen minucioso del abdomen para descartar sensibilidad abdominal, distensión, masas o un colon palpable (lo que sugiere heces retenidas).

A rectal examination should also be performed to look for:

• Anal fissures, haemorrhoids, skin tags, rectal prolapse, rectocele, skin erythema, or excoriation (may be a sign of faecal leakage).

• Resting anal sphincter tone.

• Rectal mass lesions and retained faeces (these may also be felt on external palpation around the anus). A faecal mass can be distinguished from a tumour or cyst, as firm pressure exerted by a finger will typically leave a palpable indentation in hard faeces.

• Disfunción del suelo pélvico (si corresponde) - al pedirle a la persona que 'empuje', puede haber una contracción paradójica del esfínter anal al esforzarse.

• Leakage of stool.

• Rectal or anal pain.

Causas del estreñimiento

Investigaciones

• La mayoría de los casos de estreñimiento no requieren investigación, especialmente en pacientes jóvenes con síntomas leves.

• Las indicaciones para la investigación incluyen:

  • Edad >40 años.

  • Un cambio reciente en el hábito intestinal.

  • Síntomas asociados (pérdida de peso, sangrado rectal, secreción mucosa o tenesmo).

• Las investigaciones posibles incluyen:

  • Blood tests: FBC, U&E, Ca++, TFTs.

• Referral may be required, depending on history, examination and investigation findings for consideration of:

  • Sigmoidoscopia y biopsia de mucosa anormal y normal.

  • Investigaciones especiales (por ejemplo, estudios de tránsito, fisiología anorrectal) que se indican ocasionalmente.
    

Manejo⁴

• Trata la causa.

• Increase exercise.

• Increase fluid intake.

• Increase intake of high-fibre foods (including fruits, vegetables, whole wheat, and bran).

• Schedule bathroom time to try and open bowels.

• Consider CBT (this would rarely be available on the NHS but can be found online for free).

• Considere medicamentos solo si las medidas anteriores fallan.

• Try to use most drugs for short durations only - however macrogols can be used long term and should be used for at least as long as the constipation continued.

• Aconseje a la persona que reduzca gradualmente y deje de usar laxantes una vez que esté produciendo heces blandas y formadas sin esfuerzo al menos tres veces por semana. Revise a intervalos regulares según el juicio clínico.

Terapia farmacológica³

First line drugs include bulk laxatives and osmotic laxatives.

• Bulk laxatives:

  • Increase faecal mass which stimulates peristalsis.

  • Need to be taken with plenty of fluid.

  • Examples include ispaghula husk, bran powder, methylcellulose.

  • Contra-indications include difficulty in swallowing, intestinal obstruction, colonic atony, and faecal impaction.

• Osmotic laxatives:

  • Retener líquido en el intestino.

  • Examples include macrogols and lactulose.

  • Macrogols have been shown to be superior to lactulose for improving stool frequency per week, form of stool, abdominal pain, and the need for additional medications.⁶

Second line drugs include stimulant laxatives and stool softeners.

• Stimulant laxatives:

  • Increase intestinal motility.

  • Should not be used in intestinal obstruction.

  • Examples include bisacodyl, senna and docusate sodium.

  • Se debe evitar el uso prolongado, ya que puede causar atonía colónica e hipocalemia (pero no hay buenos estudios de seguimiento a largo plazo).

  • Glycerol suppositories work as rectal stimulants.

  • Co-danthromer is a powerful stimulant laxative but has been associated with colonic and liver tumours in animal studies so is reserved for those patients towards the end of life.

• Suavizantes de heces:

  • Lubricate and soften impacted faeces.

  • Side-effects can include anal seepage and malabsorption.

  • Should not be used for a prolonged period.

Third line drugs include enemas such as sodium phosphate or micralax. They can be useful as an adjunct in impaction.

Prucalopride⁷⁸

• Prucaloprida es un 5HT de serotonina selectivo₄-receptor agonist with prokinetic properties.

• Initially approved by the National Institute for Care Excellence (NICE) for women only, this can now be used for men and women who meet the criteria.

• Prucalopride is recommended as an option for the treatment of chronic constipation when treatment with at least two laxatives from different classes, at the highest tolerated recommended doses for at least six months, has failed to provide adequate relief, and invasive treatment for constipation is being considered.

• Initially it was recommended that prucalopride should only be prescribed by a clinician with experience of treating chronic constipation, who has carefully reviewed the woman's previous courses of laxative treatments. However NICE guidance no longer states this and some local formularies make provision for GPs to initiate prescribing.

Síndrome de defecación obstruida⁹

• El síndrome de defecación obstruida (SDO) se caracteriza por una necesidad de defecar pero una capacidad reducida para expulsar el bolo fecal.

• Symptoms include unsuccessful attempts at faecal evacuation, excessive straining, pain, bleeding after defecation,, and a sense of incomplete faecal evacuation.

• Las mujeres, especialmente las multíparas, tienen más probabilidades que los hombres de presentar síntomas de ODS.

• ODS is often associated with structural defects in the rectum, such as rectocele, internal rectal prolapse, and perineal descent.

• Conservative treatments include diet, biofeedback, laxatives, and pelvic floor retraining.

• Surgery may be considered for patients not responding to conservative treatment or if a structural abnormality is present, Surgical options include stapled transanal prolapsectomy, perineal levatorplasty (STAPL), stapled transanal rectal resection (STARR), and laparoscopic ventral mesh sacrocolporectopexy.

Estreñimiento severo

Para los pacientes que no responden a las medidas conservadoras, se pueden considerar otras opciones.

Estas incluyen:

• Transanal irrigation - water is introduced into the rectum by a catheter with inflatable balloon. It is controlled by a manual unit and has a pump, leg straps and a bag to hold the water. It is self-administered by the patient. A number of systems are available (eg, Peristeen®).¹⁰

• Sacral nerve stimulation - a minimally invasive procedure whereby an electrode is placed in a posterior foramen of the sacral bone.^{11 12}

• The Malone operation - this is also called an antegrade colonic enema (ACE). A small stoma is constructed from the appendix. Through the appendicostomy a catheter is inserted to administer an enema in the caecum. Usually 1 litre is given every second day to empty the whole colorectum. In patients who no longer have the appendix, a 'neoappendix' can be created from ileum or part of the caecum.¹²

• Surgery - colectomy with ileorectal anastomosis is reserved for a very small number of patients who do not respond to any other measures.¹²