What is the next best investigation for a patient with a symptomatic inguinal hernia, who smokes 2 packs (packs of cigarettes) per day for 50 years, and complains of dysuria (painful urination) and nocturia (excessive urination at night)?

Next Investigation for Patient with Symptomatic Inguinal Hernia, Smoking History, and Urinary Symptoms

For a patient with symptomatic inguinal hernia who smokes 2 packs per day for 50 years and presents with dysuria and nocturia, ultrasound of the prostate is the most appropriate next investigation.

Rationale for Ultrasound Prostate

Analysis of Patient's Presentation

• The patient has two key clinical issues:
  1. Symptomatic inguinal hernia
  2. Lower urinary tract symptoms (LUTS) - dysuria and nocturia

Why Ultrasound Prostate is Indicated:

• The patient's urinary symptoms (dysuria and nocturia) strongly suggest a urological cause that requires evaluation 1
• According to AUA/SUFU guidelines, patients with LUTS should undergo appropriate evaluation to exclude other disorders that could cause these symptoms 1
• Nocturia and dysuria in older males often indicate potential prostatic pathology that should be assessed 1
• Ultrasound allows for:
  • Assessment of prostate size and morphology
  • Evaluation of post-void residual volume
  • Detection of urinary retention which may be associated with the hernia

Connection Between Hernia and Urinary Symptoms

• Inguinal hernias involving the bladder (inguinal bladder hernia) can cause urinary symptoms including dysuria and nocturia 2, 3
• These hernias can lead to urinary obstruction, especially in males with pre-existing prostatic enlargement 4
• Ultrasound can help determine if the hernia involves urological structures 2

Why Other Options Are Less Appropriate:

Chest X-ray

• While indicated for preoperative evaluation in a heavy smoker (100 pack-year history), it does not address the immediate urinary symptoms
• Should be performed later as part of surgical planning, not as the next investigation for the presenting urinary symptoms

ECG

• Would be part of preoperative cardiac evaluation
• Does not address the primary urinary symptoms
• Not the priority investigation for dysuria and nocturia

CT Scan

• While CT can evaluate both hernia and urinary tract, it's not the first-line investigation for LUTS
• Guidelines recommend starting with less invasive and more targeted tests 1
• CT would be appropriate if ultrasound findings suggest urinary tract obstruction or if bladder involvement in the hernia is suspected 4

Management Algorithm:

1. Initial evaluation of urinary symptoms:

   • Ultrasound of prostate to assess size, morphology, and post-void residual
   • Urinalysis to rule out infection

2. If ultrasound shows prostatic enlargement with obstruction:

   • Consider medical management of BPH before hernia repair
   • Evaluate for potential bladder involvement in the hernia

3. If ultrasound suggests bladder involvement in hernia:

   • Proceed to CT scan for detailed anatomical assessment
   • Plan for urological consultation prior to hernia repair

4. Preoperative evaluation (after urological assessment):

   • Chest X-ray (given significant smoking history)
   • ECG and cardiac risk assessment
   • Pulmonary function tests if indicated

Important Clinical Considerations:

• In patients with inguinal hernias and LUTS, bladder involvement occurs in 1-4% of cases and should be suspected 3
• Failure to identify bladder involvement in an inguinal hernia preoperatively increases risk of bladder injury during repair 3
• Heavy smokers with inguinal hernias require thorough preoperative assessment, but addressing the urological symptoms takes priority when they are the presenting complaint 1
• Rare cases of obstructive uropathy and even renal failure have been reported with inguinal hernias involving urological structures 5, 6