Snyder J A, Lipsitz D U
Division of Urology, University of Colorado Health Science Center, Denver.
Urol Clin North Am. 1991 May;18(2):197-209.
The use of urodynamic testing must be selective and based on the particular patient's complaints. In today's cost-conscious health care environment, a diagnosis based on one or two tests is preferable to exposing each patient to the full battery of available tests. For most patients, a cystometrogram and voiding cystourethrogram can confirm a variety of clinical suspicions. A cystometrogram best indicates how the bladder is behaving during filling. The voiding cystourethrogram allows the physician to observe the bladder and urethra during voiding and offers an excellent view of the anatomic relations of the urologic organs in the pelvis. The other important benefit of urodynamics is the objective data made available in hardcopy as a baseline study to be utilized for comparison in the future. The normal sequence of testing is a noninvasive uroflow study to determine the baseline flow rate. The postvoiding residual volume of urine is then determined. A cystometrogram and electromyography can then be done, the latter if there is a suggestion of neurologic disease or if otherwise indicated to determine bladder behavior on filling. Variations that are helpful when a patient fails to have a bladder contraction include having the patient in an upright or seated position during the test. A bethanechol supersensitivity test may be indicated as well. The urethral pressure profile may be done as the catheter is withdrawn and the bladder is already filled. The filled invasive flow rate can then be compared with the free flow rate. Sometimes, one of these rates is abnormal, and there is a question about whether the abnormality is real. The residual urine volume can be determined by subtracting the volume the patient voids from the filling volume. In the end, the key to urodynamic evaluation is the interpretation of the test, which should be made only by the individual actually performing the test. It truly is necessary for the physician to be there in person. Selective use of urodynamics can target an appropriate treatment for most patients. The female patient who complains of incontinence in whom the history suggests detrusor instability may benefit from a trial of cholinolytic therapy if no anatomic defect is present. In this type of patient, a surgical procedure may not be of benefit, whereas the cholinolytic therapy probably will work. This is a good reason for always choosing the appropriate urodynamic tests for evaluating and planning treatment for patients with urinary incontinence.
尿动力学检查的应用必须具有选择性，并基于患者的具体主诉。在当今注重成本的医疗保健环境中，基于一两项检查做出诊断，要优于让每位患者都接受全套现有检查。对于大多数患者而言，膀胱压力容积测定和排尿性膀胱尿道造影能够证实多种临床怀疑。膀胱压力容积测定最能表明膀胱在充盈过程中的表现。排尿性膀胱尿道造影可让医生在排尿过程中观察膀胱和尿道，并能很好地显示盆腔内泌尿器官的解剖关系。尿动力学的另一个重要益处是能提供硬拷贝形式的客观数据，作为基线研究，供日后进行比较。正常的检查顺序是先进行无创尿流率研究以确定基线流速。然后测定排尿后残余尿量。接着可进行膀胱压力容积测定和肌电图检查，如果怀疑有神经疾病或有其他指征表明需要确定膀胱充盈时的表现，就进行肌电图检查。当患者膀胱无收缩时，一些有助于检查的变通方法包括让患者在检查过程中保持直立或坐姿。也可能需要进行氨甲酰甲胆碱超敏试验。当导管拔出且膀胱已充盈时，可进行尿道压力分布图检查。然后可将充盈时的侵入性流速与自由流速进行比较。有时，其中一种流速异常，就会存在该异常是否真实的疑问。残余尿量可通过从充盈量中减去患者排尿量来确定。最后，尿动力学评估的关键在于对检查结果的解读，而这应由实际进行检查的人员来完成。医生亲自在场确实很有必要。选择性应用尿动力学可为大多数患者确定合适的治疗方案。主诉尿失禁且病史提示逼尿肌不稳定的女性患者，如果不存在解剖缺陷，可能会从胆碱能抑制剂治疗试验中获益。在这类患者中，手术可能并无益处，而胆碱能抑制剂治疗可能有效。这就是始终为尿失禁患者选择合适的尿动力学检查以进行评估和制定治疗方案的一个很好的理由。
