Description/Etiology
Transcription
Description/Etiology
quickLESSON about... Benign Prostatic Hyperplasia Description/Etiology Benign prostatic hyperplasia (BPH; also called benign prostatic hypertrophy) is a nonmalignant condition in which excessive smooth muscle and epithelial cell proliferation results in an enlarged prostate gland that constricts or deforms the lower urinary tract and causes difficulty with urination. BPH occurs primarily in older men, affecting 50% of men by age 60 and 90% of men by age 85. BPH is rare in men under the age of 40. Although the etiology of BPH is not fully understood, animal studies suggest age-related sex hormone imbalances involving testosterone, estrogen, and dihydrotestosterone (DHT) may cause excessive growth of prostatic tissues, causing the gland to enlarge and compress the urethra and even protrude into the bladder neck, resulting in urinary outlet irritation, obstruction, and urinary retention. The hypothesized etiologies of BPH suggest prostate cell growth due to reactivation of genes in the prostate cells and a role of impaired catechol-omethyl transferase gene activity. Complications of BPH include bladder stones, prostatitis, hematuria, urinary retention, and renal failure. BPH is diagnosed based on patient history and a variety of tests, including digital rectal examination (DRE), prostate-specific antigen (PSA) blood test, transrectal ultrasound (TRUS), and prostate biopsy. BPH must be differentiated from prostate cancer (CaP), urinary tract infection (UTI), prostatitis, urethral stricture, overactive bladder, neurogenic bladder, bladder cancer, poorly controlled diabetes, and neurologic conditions that produce neurogenic bladder and bladder symptoms (e.g., Parkinson’s disease, diabetic autonomic neuropathy, multiple sclerosis, spinal cord injury). ICD-9 600.90 Treatment options for BPH include surgery and use of pharmacologic agents, such as non-selective or selective alpha-adrenergic blockers, to help relax the smooth muscle tissue of the prostate and bladder neck, improving urinary flow; 5-alpha reductase inhibitors to reduce prostate size; stool softeners for constipation; analgesics for pain; muscle relaxants to reduce pelvic muscle spasms; and antibiotics for infection. Surgical procedures to remove part or all of the prostate gland include transurethral resection of the prostate (TURP) and suprapubic or retropubic prostatectomy. Minimally invasive surgical procedures include holmium laser ablation of the prostate, transurethral vaporization of the prostate, interstitial laser coagulopathy, high-frequency focused ultrasound, transurethral needle ablation, transurethral microwave thermoplasty, transurethral balloon dilatation therapy, transurethral ethanol ablation, and water-induced thermoplasty. (For more information, see Quick Lesson About…Prostatectomy, Benign Prostatic Hyperplasia.) The overall prognosis is fairly good, as treatment improves symptoms in 70–80% of cases. Facts and Figures Authors Gilberto Cabrera, MD Tanja Schub, BS Reviewers Eliza Schub, RN, BSN Cinahl Information Systems Glendale, California Rosalyn Robinson, RN, DNP, APNP, FNP-BC Cinahl Information Systems Glendale, California Nursing Executive Practice Council Glendale Adventist Medical Center Glendale, California Editor Diane Pravikoff, RN, PhD, FAAN Cinahl Information Systems BPH is the most common cause of urinary tract obstruction in men over the age of 50, affecting ~ 14 million men in the United States and ~ 30 million men worldwide. Evidence for racial predisposition is not supported. Up to 33% of men with BPH have coexisting CaP. Risk Factors Risk factors for BPH include advanced age, intact testes, and family history of BPH. Abdominal obesity and consumption of a diet high in fat and red meat are possible risk factors. The risk for complications increases proportionally with the amount of prostatic enlargement. Signs and Symptoms/Clinical Presentation Obstructive symptoms include urinary hesitancy or retention, decreased force and caliber of the urine stream, sensation of incomplete bladder emptying, straining to urinate, and post-void dribbling. Irritative symptoms include increased urinary urgency, frequency, and nocturia. Assessment 44 Patient History •• Ask the patient about history of urinary dysfunction and family history of BPH 44 Physical Findings of Particular Interest June 8, 2012 •• DRE may reveal smooth, firm, elastic enlargement of the prostate •• Physical examination may reveal bladder distention and neurological dysfunction (e.g., sensory and/or motor) Published by Cinahl Information Systems. Copyright©2012, Cinahl Information Systems. All rights reserved. No part of this may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher. Cinahl Information Systems accepts no liability for advice or information given herein or errors/omissions in the text. It is merely intended as a general informational overview of the subject for the healthcare professional. Cinahl Information Systems, 1509 Wilson Terrace, Glendale, CA 91206 44 Laboratory Tests That May Be Ordered •• •• •• •• PSA levels may be elevated in BPH and CaP Serum chemistry studies may reveal ↑ serum blood urea nitrogen and creatinine levels UA and urine culture to evaluate for UTI, prostatitis, hematuria, and pyuria Histopathologic testing of biopsied prostate tissue is negative for malignancy in BPH •• •• •• •• Pressure flow studies and flow rate test to assess for urinary flow abnormalities TRUS to assess prostate size; abdominal ultrasound to assess for hydronephrosis or increased post-void residual Cystoscopy to assess for renal obstruction Chest X-ray and EKG to evaluate pre- and postoperative pulmonary and cardiac status 44 Other Diagnostic Tests Treatment Goals 44 Provide Supportive Care During Treatment and Monitor for Complications •• Assess all physiologic systems and review laboratory/diagnostic study results for abnormalities; assess for pain, voiding dysfunction, infection, and constipation –– Administer antibiotics for infection, nonselective alpha-adrenergic blockers (e.g., doxazosin, terazosin), selective alpha-adrenergic blockers (e.g., terazosin, tamsulosin) to help relax the bladder, 5-alpha reductase inhibitors (e.g., finasteride, dutasteride) to reduce size of enlarged prostate, stool softeners and laxatives for constipation and to reduce straining, muscle relaxants to reduce pelvic muscle spasms, and analgesics (e.g., ibuprofen, aspirin) for pain –– Insert an indwelling urinary catheter if ordered for urinary retention/obstruction and ensure meticulous hygiene; monitor catheter patency and urine collection, and avoid rapid bladder decompression •• Follow facility pre- and postsurgical protocols if patient becomes a surgical candidate; reinforce pre- and postsurgical education and verify completion of facility informed consent documents; monitor closely for complications following surgical intervention (e.g., septic shock, renal failure, heart failure) –– Monitor vital signs, intake and output, nutritional and respiratory status, response to treatment, and for medication side effects; ensure bed rest and adherence to a fluid restrictive diet, and provide sitz baths for comfort, as ordered 44 Educate and Provide Emotional Support •• Assess patient’s anxiety level and coping ability; express empathy, and educate about BPH, potential complications, and treatment risks and benefits Food for Thought 44 Although sexual function is initially affected in some cases after surgery for BPH, it generally returns fully with time. Retrograde ejaculation (i.e., semen entering the bladder instead of exiting through the urethra during ejaculation), which can cause sterility, occurs rarely 44 Some men with BPH use alternative treatments (e.g., herbs such as saw palmetto, African plum tree, rye, stinging nettle root), although their effectiveness has not been proven 44 Alpha-1 and alpha-2 receptors, the targets of alpha-adrenergic blockers, are found in a variety of tissues other than prostate tissue, including platelets; in a recent study of the effects of the alpha-adrenergic blockers doxazosin, terazosin, alfuzosin, and tamsulosin on endothelial function and coagulation parameters in 89 patients with BPH, the researchers found that these drugs may decrease cardiovascular risk by reducing platelet aggregation and protecting endothelial function (Alan et al., 2011) Red Flags 44 Avoid checking for fecal impaction, as a rectal examination may precipitate bleeding 44 Some alpha-adrenergic blockers (e.g., alfuzosin, doxazosin, terazosin) produce a vasodilatory effect that has been associated with increased risk of developing vascular adverse events (e.g., presyncope, syncope) What Do I Need to Tell the Patient/Patient’s Family? 44 Advise the patient to increase water intake to flush the bladder, avoid straining during bowel movements, eat a nutritious diet but avoid spicy foods, avoid alcoholic or caffeinated drinks, avoid heavy lifting, and avoid driving or operating heavy machinery 44 Emphasize the importance of continued medical surveillance, including PSA screening 44 Educate to seek immediate medical attention for new or recurrent urinary symptoms, surgical complications, or medication side effects 44 Recommend finding additional information from the National Kidney and Urologic Diseases Information Clearinghouse (NKUDIC) at www.kidney.niddk.nih.gov References •• Alan, C., Kirilmaz, B., Koçoğlu, H., Ersay, A. R., Ertung, Y., & Eren, A. E. (2011). Comparison of effects of alpha receptor blockers on endothelial functions and coagulation parameters in patients with benign prostatic hyperplasia. Urology, 77(6), 1439-1443. •• Deters, L. A., Costabile, R. A., Leveillee, R. J., Moore, C. R., & Patel, V. R. (2011). Benign prostatic hypertrophy. Medscape Reference. Retrieved May 8, 2012, from http://emedicine.medscape.com/article/437359-overview •• DynaMed. (2012, March 20). Benign prostatic hypertrophy (BPH). Ipswich, MA: EBSCO Publishing. Retrieved May 8, 2012, from http://search.ebscohost.com/login.aspx?direct=true&db=dme&AN=116944&site=dynamed-live&scope=site •• Evans, J. D., Pace, K., & Evans, E. W. (2011). Natural therapies used by adult men for the treatment of erectile dysfunction, benign prostatic hyperplasia, and for augmenting exercise performance. Journal of Pharmacy Practice, 24(3), 323-331. •• Longstroth, D. (2012). Prostatic hyperplasia, benign (BPH). In F. J. Domino (Ed.), The 5-minute clinical consult 2012 (20th ed., pp. 1068-1069). Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins.