After three years on lisinopril and 7 months post‑fistulotomy, I have reduced sexual arousal and diminished bladder‑filling sensation; does this indicate hypertension or hypotension, given that warm‑water immersion does not improve the symptoms?

Blunted Sexual and Urinary Sensation After Fistulotomy and Lisinopril Use

Direct Answer

Your symptoms of blunted sexual arousal and diminished bladder sensation are most likely related to nerve damage from the fistulotomy surgery rather than being caused by hypertension or hypotension, though lisinopril may be contributing to the sexual dysfunction component. The lack of improvement with warm water immersion does not definitively rule out either hypertension or hypotension as contributing factors, but it does suggest a structural or neurological cause rather than a purely vascular one 1.

Understanding Your Symptoms

Fistulotomy-Related Nerve Damage

• Anal fistulotomy can damage pudendal nerves and pelvic floor nerves, which control both sexual sensation and bladder filling awareness 1.
• Blunted urination feelings (reduced bladder filling sensation) 7 months post-surgery strongly suggests surgical nerve injury rather than medication effects, as this is a recognized complication of pelvic/perineal surgery 1.
• Sexual dysfunction following pelvic surgery is well-documented, with pain and nerve damage being primary mediators of reduced arousal 1.

Lisinopril's Contribution

• ACE inhibitors like lisinopril can cause sexual dysfunction, but this typically manifests as erectile dysfunction rather than blunted sensation 1.
• Lisinopril does not typically cause reduced bladder sensation; this is not a recognized side effect of ACE inhibitors 2.
• The JNC-7 guidelines note that ACE inhibitors have NOT been observed to increase the incidence of sexual dysfunction in controlled trials, unlike beta-blockers and thiazide diuretics 1.
• However, blood pressure lowering itself may reduce perfusion to genital organs, potentially contributing to arousal difficulties 1.

Why the Warm Water Test Doesn't Prove Anything

Vascular Response Limitations

• Warm water immersion primarily affects superficial blood vessels and does not reliably test deep pelvic/genital perfusion 1.
• Both hypertension and hypotension can coexist with nerve damage, and vascular responses may be blunted when nerves are injured 1.
• The absence of symptom improvement with warmth suggests a neurological rather than purely vascular etiology, but does not exclude blood pressure as a contributing factor 1.

Clinical Approach to Your Situation

Immediate Assessment Needed

• Check your actual blood pressure readings to determine if you have hypertension, hypotension, or normal blood pressure 1.
• Assess for orthostatic hypotension (blood pressure drop when standing), which can occur with lisinopril and cause various symptoms 2.
• Evaluate post-void residual urine volume to determine if you have bladder emptying dysfunction from nerve damage 1.

Distinguishing Nerve Damage from Medication Effects

• Nerve damage from surgery would cause:

  • Reduced sensation in a specific distribution (perineal/genital area) 1
  • Persistent symptoms that don't fluctuate with blood pressure 1
  • Possible associated bowel control changes 1

• Lisinopril-related effects would cause:

  • Erectile dysfunction (if male) rather than sensory blunting 1
  • Symptoms that might improve if medication is temporarily held 1
  • No effect on bladder filling sensation 2

Treatment Algorithm

Step 1: Confirm the diagnosis

• Urodynamic testing should be performed to assess bladder sensation, capacity, and nerve function 1.
• Consider pelvic floor assessment to evaluate for surgical nerve injury 1.

Step 2: Address medication factors

• If sexual dysfunction is bothersome and blood pressure is well-controlled, discuss with your physician switching from lisinopril to an ARB or calcium channel blocker, which have lower rates of sexual side effects 1.
• Do not discontinue lisinopril without medical supervision, as abrupt withdrawal can cause blood pressure fluctuations 2.

Step 3: Manage nerve-related symptoms

• Pelvic floor physical therapy can improve sexual pain, arousal, and bladder sensation in patients with pelvic surgery complications 3.
• For persistent bladder sensation problems, consider urological evaluation for possible neurogenic bladder 1.
• Cognitive behavioral therapy has strong evidence for improving sexual function in patients with medical conditions affecting sexuality 3.

Critical Pitfalls to Avoid

• Do not assume all symptoms are medication-related when you have had recent pelvic surgery; the timing (7 months post-fistulotomy) strongly implicates surgical complications 1.
• Do not stop lisinopril abruptly, as this can cause rebound hypertension if you actually have high blood pressure 2.
• Do not ignore bladder symptoms, as reduced sensation can lead to urinary retention and kidney damage if severe 1, 2.
• Avoid attributing everything to either "hyper" or "hypo" tension when the clinical picture suggests nerve injury as the primary problem 1.

Bottom Line

Your symptoms are most consistent with pudendal or pelvic nerve damage from the fistulotomy surgery, potentially compounded by mild vascular effects from lisinopril 1. The warm water test is not a valid diagnostic tool for distinguishing hypertension from hypotension in this context 1. You need urodynamic testing and possibly pelvic floor evaluation to confirm nerve injury, and a discussion with your physician about whether lisinopril is contributing to sexual dysfunction 1, 3.