BENIGN PROSTATIC HIPERPLASIA (BPH)

2008-08-20T11:40:00.006+07:00

Benign prostatic hyperplasia symptoms are classified as obstructive or irritative. Obstructive symptoms include hesitancy, intermittency, incomplete voiding, weak urinary stream, and straining. Irritative symptoms include frequency of urination, which is called nocturia when occurring at night time, and urgency (compelling need to void that can not be deferred). These obstructive and irritative symptoms are evaluated using the International Prostate Symptom Score (IPSS) questionnaire, designed to assess the severity of BPH. BPH can be a progressive disease, especially if left untreated. Incomplete voiding results in stasis of bacteria in the bladder residue and an increased risk of urinary tract infections. Urinary bladder stones, are formed from the crystallisation of salts in the residual urine. Urinary retention, termed acute or chronic, is another form of progression. Acute urinary retention is the inability to void, while in chronic urinary retention the residual urinary volume gradually increases, and the bladder distends. Some patients who suffer from chronic urinary retention may eventually progress to renal failure, a condition termed obstructive uropathy.

Etiology

Androgens (testosterone and related hormones) are considered to play a permissive role in BPH by most experts. This means that androgens have to be present for BPH to occur, but do not necessarily directly cause the condition. This is supported by the fact that castrated boys do not develop BPH when they age, unlike intact men. Additionally, administering exogenous testosterone is not associated with a significant increase in the risk of BPH symptoms. Dihydrotestosterone (DHT), a metabolite of testosterone is a critical mediator of prostatic growth. DHT is synthesized in the prostate from circulating testosterone by the action of the enzyme 5α-reductase, type 2. This enzyme is localized principally in the stromal cells; hence, these cells are the main site for the synthesis of DHT. DHT can act in an autocrine fashion on the stromalie cells or in paracrine fashion by diffusing into nearby epithelial cells. In both of these cell types, DHT binds to nuclear androgen receptors and signals the transcription of growth factors that are mitogenic to the epithelial and stromal cells. DHT is 10 times more potent than testosterone because it dissociates from the androgen receptor more slowly. The importance of DHT in causing nodular hyperplasia is supported by clinical observations in which an inhibitor of 5α-reductase is given to men with this condition. Therapy with 5α-reductase inhibitor markedly reduces the DHT content of the prostate and in turn reduces prostate volume and, in many cases, BPH symptoms. There is growing evidence that estrogens play a role in the etiology of BPH. This is based on the fact that BPH occurs when men generally have elevated estrogen levels and relatively reduced free testosterone levels, and when prostate tissue becomes more sensitive to estrogens and less responsive to DHT. Cells taken from the prostates of men who have BPH have been shown to grow in response to high estradiol levels with low androgens present. Estrogens may render cells more susceptible to the action of DHT.

Treatment

Men who have BPH with symptoms usually need some kind of treatment at some time. However, a number of researchers have questioned the need for early treatment when the gland is just mildly enlarged. The results of their studies indicate that early treatment may not be needed because the symptoms of BPH clear up without treatment in as many as one-third of all mild cases. Instead of immediate treatment, they suggest regular checkups to watch for early problems. If the condition begins to pose a danger to the patient's health or causes a major inconvenience to him, treatment is usually recommended. Since BPH can cause urinary tract infections, a doctor will usually clear up any infection with antibiotics before treating the BPH itself. Although the need for treatment is not usually urgent, doctors generally advise going ahead with treatment once the problems become bothersome or present a health risk. The following section describes the types of treatment that are most commonly used for BPH.

Drug Treatment

Over the years, researchers have tried to find a way to shrink or at least stop the growth of the prostate without using surgery. The FDA has approved six drugs to relieve common symptoms associated with an enlarged prostate. Finasteride (Proscar), FDA-approved in 1992, and dutasteride (Avodart), FDA-approved in 2001, inhibit production of the hormone DHT, which is involved with prostate enlargement. The use of either of these drugs can either prevent progression of growth of the prostate or actually shrink the prostate in some men. The FDA also approved the drugs terazosin (Hytrin) in 1993, doxazosin (Cardura) in 1995, tamsulosin (Flomax) in 1997, and alfuzosin (Uroxatral) in 2003 for the treatment of BPH. All four drugs act by relaxing the smooth muscle of the prostate and bladder neck to improve urine flow and to reduce bladder outlet obstruction. The four drugs belong to the class known as alpha blockers. Terazosin and doxazosin were developed first to treat high blood pressure. Tamsulosin and alfuzosin were developed specifically to treat BPH. The Medical Therapy of Prostatic Symptoms (MTOPS) Trial, supported by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), recently found that using finasteride and doxazosin together is more effective than using either drug alone to relieve symptoms and prevent BPH progression. The two-drug regimen reduced the risk of BPH progression by 67 percent, compared with 39 percent for doxazosin alone and 34 percent for finasteride alone.

Surgical Treatment

Most doctors recommend removal of the enlarged part of the prostate as the best long-term solution for patients with BPH. With surgery for BPH, only the enlarged tissue that is pressing against the urethra is removed; the rest of the inside tissue and the outside capsule are left intact. Surgery usually relieves the obstruction and incomplete emptying caused by BPH. The following section describes the types of surgery that are used.

Transurethral surgery. In this type of surgery, no external incision is needed. After giving anesthesia, the surgeon reaches the prostate by inserting an instrument through the urethra. A procedure called transurethral resection of the prostate (TURP) is used for 90 percent of all prostate surgeries done for BPH. With TURP, an instrument called a resectoscope is inserted through the penis. The resectoscope, which is about 12 inches long and 1/2 inch in diameter, contains a light, valves for controlling irrigating fluid, and an electrical loop that cuts tissue and seals blood vessels. During the 90-minute operation, the surgeon uses the resectoscope's wire loop to remove the obstructing tissue one piece at a time. The pieces of tissue are carried by the fluid into the bladder and then flushed out at the end of the operation. Most doctors suggest using TURP whenever possible. Transurethral procedures are less traumatic than open forms of surgery and require a shorter recovery period. One possible side effect of TURP is retrograde, or backward, ejaculation. In this condition, semen flows backward into the bladder during climax instead of out the urethra. Another surgical procedure is called transurethral incision of the prostate (TUIP). Instead of removing tissue, as with TURP, this procedure widens the urethra by making a few small cuts in the bladder neck, where the urethra joins the bladder, and in the prostate gland itself. Although some people believe that TUIP gives the same relief as TURP with less risk of side effects such as retrograde ejaculation, its advantages and long-term side effects have not been clearly established.

Open surgery. In the few cases when a transurethral procedure cannot be used, open surgery, which requires an external incision, may be used. Open surgery is often done when the gland is greatly enlarged, when there are complicating factors, or when the bladder has been damaged and needs to be repaired. The location of the enlargement within the gland and the patient's general health help the surgeon decide which of the three open procedures to use. With all the open procedures, anesthesia is given and an incision is made. Once the surgeon reaches the prostate capsule, he or she scoops out the enlarged tissue from inside the gland.

Laser surgery. In March 1996, the FDA approved a surgical procedure that employs side-firing laser fibers and Nd: YAG lasers to vaporize obstructing prostate tissue. The doctor passes the laser fiber through the urethra into the prostate using a cystoscope and then delivers several bursts of energy lasting 30 to 60 seconds. The laser energy destroys prostate tissue and causes shrinkage. As with TURP, laser surgery requires anesthesia and a hospital stay. One advantage of laser surgery over TURP is that laser surgery causes little blood loss. Laser surgery also allows for a quicker recovery time. But laser surgery may not be effective on larger prostates. The long-term effectiveness of laser surgery is not known. Newer procedures that use laser technology can be performed on an outpatient basis.

Photoselective vaporization of the prostate (PVP). PVP uses a high-energy laser to destroy prostate tissue and seal the treated area.

Interstitial laser coagulation. Unlike other laser procedures, interstitial laser coagulation places the tip of the fiberoptic probe directly into the prostate tissue to destroy it.

Medications

Alpha blockers (α₁-adrenergic receptor antagonists) provide symptomatic relief of BPH symptoms. Available drugs include doxazosin, terazosin, alfuzosin and tamsulosin. Older drugs, phenoxybenzamine and prazosin are not recommended for treatment of BPH.^[5] Alpha-blockers relax smooth muscle in the prostate and the bladder neck, and decrease the degree of blockage of urine flow. Alpha-blockers may cause ejaculation back into the bladder (retrograde ejaculation). The 5α-reductase inhibitors (finasteride dutasteride) are another treatment option. This medication inhibits 5a-reductase, which in turn inhibits production of DHT, a hormone responsible for enlarging the prostate. When used together with alpha blockers a reduction of BPH progression to acute urinary retention and surgery has been noted in patients with larger prostates. Though former research indicated the efficacy of Serenoa repens (saw palmetto) fruit extracts in alleviating mild-to-moderate BPH symptoms,^[7] a recent double-blind study did not demonstrate any efficacy greater than that of a placebo for moderate-to-severe symptoms.^[8] Herbal medicines that have research support in systematic reviews include beta-sitosterol from Hypoxis rooperi (African star grass) and pygeum (extracted from the bark of Prunus africana), while there is less substantial support for the efficacy of Cucurbita pepo (pumpkin) seed and Urtica dioica (stinging nettle) root.^[9] At least one double-blind trial has also supported the efficacy of rye flower pollen. Sildenafil shows some symptomatic relief, suggesting a possible common etiology with erectile dysfunction.

HYPOXIA AND ABNORMAL RESPIRATORY RHYTHMS

2008-01-02T08:20:00.000+07:00

Terms Related to Hypoxia

Respiratroy Insufficiency, inability of the lungs to maintain normal arterial bloods gas levels when the individual is breathing 21% oxygen (at sea level)
Hyperpnea, excessively high rate of alveolar ventilation
Hypopnea, low rate of alveolar ventilation, that is, underrespiration
Hypocarbia (hypocapnia), depressed blood carbondioxide level
Acapnia, absence of carbonedioxide in the blood (this state is incompatible with life)

Signs of Hypoxia

Increased rapid pulse
Rapid, shallow respirations and dyspnea
Increased restlessness or lightheadedness
Flaring of the nares
Substernal or intercostal retractions
Cyanosis

Abnormal Respiratory Rhythms

Cheyne-Stokes breathing. Marked rhythmic waxing and waning of respirationsfrom very deep to very shallow breathing and temporary apnea (cessation of breathing); common causes include congestive heart failure, increased intacranial pressure and drug overdose.
Apneustic breathing. Prolonged gasping inspiration followed by a very short, usually inefficient, expiration; associated with central nervous system disorders.
Biot's breathing. Shallow breaths interrupted by apnea; may be seen in healthy people and in clients with central nervous system disorders.

Does Thermal Biofeedback Combined with Progressive Muscle Relaxation Blood Pressure in Clients with Essential Hipertension?

2008-01-02T07:10:00.000+07:00

This study measured the effect of thermal biofeedback training combined with progressive relaxation training in the treatment of female client who were diagnosed with essential hypertension. The sample consisted of 19 adult women 30 to 59 years of age who were not taking antihypertensive medication. Blood pressure decline was measured on the treatment group of 11 clients, who underwent thermal biofeedback combined with progressive muscle relaxation training, and on the control group of 8 clients who underwent only progressive muscle relaxation training.

For both groups, baseline blood pressure was measured four times for 2 weeks. For the treatment group, blood pressure was measured twice, once before and once after each of the eight sessions of thermal biofeedback training for 4 weeks. For the control group, blood pressure was measured at every other visit to a clinic for progressive muscle relaxation self-training, twice before and after the self-training. On average, the treatment group[ experienced a decline in systolic blood pressure of 20.6 mm Hg and a decline in diastolic blood pressure of 14.4 mm Hg. In the control group, both systolic and diastolic blood pressure tended to increase.

Implications: Nurse should be knowledgeable about thermal biofeedback and progressive muscle relaxation techniques so that they can teach clients effective ways to manage essential hypertension in conjunction with other physician-prescribe treatments.

PHYSIOLOGIC MANIFESTATIONS OF STRESS

2007-12-30T13:43:00.000+07:00

Pupile dilate of increase visual perception when serious threats to the body arise.

Sweat production (dhiaphoresis) increases to control elevated body heat due to increased metabolism.

The heart rate increases, which leads to an increased pulse rate to transport nutrients and by product of metabolism more efficiently.

Skin is pallid because of constrictions of peripheral blood vessels, an effect of norepinephrine.

Blood pressure increase because of

Constriction of vessels in blood reservoirs, such as the skin, kidneys, and most large interior organs.
Increased secretion of rennin, an effect of norepinephrine.
Increased sodium and water retention due to release of mineralocorticoids, which resultsin increased blood volume.
Increased cardiac output.
The rate and depth of respirations increase because of dilation of the bronchioles, promoting hyperventilations.

Urinary output decreases.

The mouth may be dry.

Peristalsis of the intestines decreases, resulting in possible constipations and flatus.

For serious threats, mental alertness improves.

Muscle tensions incrase to prepare for rapid motor activity or defense.

Blood sugar increases becauseof release of glucocorticoids and gluconeogenesis.

Lethargy, mental lassitude, inactivity (parasympathetic dominance) may ensue.

There may be decreased physiologic functioning and loss of skeletal muscle tone (parasympathetic dominance)

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