Severe constipation, requiring fecal disimpaction and rectal enemas, can be excruciatingly painful for patients. Administering sedatives and opioids to help alleviate this pain poses a challenge, because many of the patients are elderly and tend to be more sensitive to these medications. Furthermore, there may be increased vagal tone when straining, leading to hypotension and bradycardia and which can result in defecation-related syncope. 1 Also, opioids can exacerbate constipation. Herein we present 2 cases and tricks on achieving better pain control.
Case 1: Painful disimpaction
A 75-year-old man presents to the Emergency Department (ED) with severe constipation. He reports having no bowel movements for a week, despite multiple laxatives and 2 Fleets enemas. The provider suspects fecal impaction and the rectal exam confirms this suspicion. The provider prepares for digital disimpaction, which is often a painful procedure.
Trick of the Trade
Use topical 2% lidocaine jelly (10 mL Sterile Pak Uro-Jet) to provide rectal lubrication as well as topical anesthesia. It is pre-dosed and in an applicator that makes rectal insertion simple. Administer all 10 mL of the jelly 5 minutes prior to the disimpaction procedure for the lidocaine to take effect. Hopefully with better pain control, manually break up the hard stool and remove it with a gloved index finger in a slightly bent, “hooking” fashion.2
Case 2: Painful rectal enemas
A 59-year-old woman presents to the ED with severe constipation. She reports that her stools have been scant and hard, but now she is having significant rectal pain when trying to have a bowel movement. She self-administered a Fleets enema prior to arrival, but it was too painful to expel the stool. You attempt a soap suds or milk and molasses enema in the ED, but the patient is retaining the stool and enema secondary to peri-rectal pain.
Trick of the Trade
Administer an enema slowly as tolerated by the patient. Subsequently administer 10 mL of 2% lidocaine jelly rectally after the patient has retained the enema for about 20 minutes. The lidocaine provides lubrication and topical anesthesia to the rectal area, facilitating easier passage of the stool and enema.
Caution: Lidocaine systemic absorption
Lidocaine absorption via mucous membranes is varied and the extent depends on the concentration and the amount administered. Avoid repeated doses in short intervals. Avoid use in sepsis or severely traumatized mucosa since this could result in more systemic absorption. The maximum recommended dose of lidocaine is 4.5 mg/kg.
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1.Wenzke K, Walsh K, Kalscheur M, et al. Clinical Characteristics and Outcome of Patients with Situational Syncope Compared to Patients with Vasovagal Syncope. Pacing Clin Electrophysiol. 2017;40(5):591-595. https://www.ncbi.nlm.nih.gov/pubmed/28244210.
2.Araghizadeh F. Fecal impaction. Clin Colon Rectal Surg. 2005;18(2):116-119. https://www.ncbi.nlm.nih.gov/pubmed/20011351.