Macrohematuria
Conditions
Brief summary
Macroscopic haematuria is a common urological emergency. Diagnostic cystoscopy is the gold standard for identifying the bleeding source; however, blood and clots within the bladder significantly impair endoscopic visibility when saline is used as the distension medium. Air-based cystoscopy, a technique first described in the 19th century, exploits the immiscibility of gas and blood to maintain clear visualisation even during active bleeding. Despite its theoretical advantages, no randomised clinical data exist to support its use. AIROSCOPY is a prospective, randomised, controlled, single-centre superiority study comparing air-based versus saline-based flexible cystoscopy in patients with macroscopic haematuria (Grade III-V). Patients are randomised 1:1. Only the index cystoscopy (first randomised modality) contributes to all study endpoints. A second cystoscopy with the alternative modality is performed solely for patient safety to ensure no diagnostic disadvantage from study participation. This second examination is not analysed. The primary endpoint is identification of the bleeding source during the index cystoscopy (binary: yes/no). Secondary endpoints include time to source identification, total procedure duration, urologist-rated visibility (Likert scale), and patient comfort (Likert scale).
Detailed description
Background: Continuous bladder irrigation (CBI) is the current standard management for haematuria, but can delay diagnostic cystoscopy. Gas-based cystoscopy may allow earlier and clearer visualisation of the bladder mucosa. Design: Prospective, randomised (1:1), controlled, parallel-group, open-label, single-centre superiority trial. Randomisation is stratified by haematuria grade and history of transurethral resection (TUR-B/P), using REDCap. Intervention: Index cystoscopy with either air (up to 240 ml by syringe) or saline (up to 240 ml by syringe), according to randomisation. A second cystoscopy with the alternative medium follows immediately, exclusively to ensure no diagnostic disadvantage for the patient (results not analysed). Sample size: N=40 (20 per arm), based on detection rates of 86% (air) vs. 38% (saline), two-sided α=0.05, 80% power, with 20% attrition allowance. Statistics: Chi-square test (Fisher's exact test) for the primary endpoint; risk ratio and risk difference with 95% CI reported.
Interventions
PROCEDUREAir-based flexible cystoscopy
Flexible cystoscopy with manual air insufflation (up to 240 ml) via bladder syringe for bladder distension and visualisation.
PROCEDURESaline-based flexible cystoscopy
Flexible cystoscopy with manual saline irrigation (up to 240 ml, 0.9% NaCl) via bladder syringe for bladder distension and visualisation.
Sponsors
Kantonsspital Baden
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE
Intervention model description
Flexible cystoscopy using air as the distension medium (up to 240 ml, manually administered via bladder syringe). This is the index cystoscopy for patients randomised to air.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Persistent macroscopic haematuria Grade III-V within 48 hours after hospitalisation * Age ≥ 18 years * Unexplained macroscopic haematuria requiring diagnostic cystoscopy * Ability to give written informed consent
Exclusion criteria
* Pregnant or lactating women * Haemodynamic instability or urgent need for operative or interventional cystoscopy (requiring cystoscopy within \< 24 hours of screening) * Ureteral stent in situ * Active urinary tract infection * Transurethral resection of the bladder (TURB) or prostate (TURP) within the last 6 weeks
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Identification of the underlying cause of macroscopic haematuria during the index cystoscopy | Immediately after completion of the index cystoscopy (intraoperative) | Binary outcome (yes/no). Assessed in real time by the operating urologist during the index procedure and documented immediately after completion. 'Yes' if a specific bleeding source (e.g., tumour, prostate bleeding, stone, vascular lesion) is identified; 'No' otherwise. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Time to source identification | Intraoperative | Minutes from insertion of the cystoscope to first identification of the bleeding source during the index cystoscopy. |
| Total procedure duration | Intraoperative | Minutes from insertion to removal of the cystoscope during the index cystoscopy. |
| Urologist-rated visibility | Immediately after index cystoscopy | 5-point Likert scale (1 = very poor to 5 = excellent), completed by the operating urologist immediately after the index cystoscopy. |
| Patient comfort | Immediately after index cystoscopy | Description: 5-point Likert scale (1 = very uncomfortable to 5 = very comfortable), completed by the patient immediately after the index cystoscopy. |
Countries
Switzerland
Contacts
CONTACTLasse Petersen, Dr. med. univ.
Outcome results
None listed