By Z. Peer. Brown University.
It seems to be especially useful when there is an elevation in the hormone prolactin buy generic propranolol 40 mg line, which can disrupt the menstrual cycle and contribute to infertility buy generic propranolol 40 mg on-line. Chasteberry can inhibit prolactin secretion and has been shown to correct menstrual irregularities caused by mild elevations of prolactin buy generic propranolol 40 mg. General Recommendations • Identify and eliminate exposure to environmental hazards 40mg propranolol amex, including pesticides, solvents, heavy metals, and other toxins • Utilize effective stress-reduction techniques (employ psychological counseling if needed) • Avoid cigarette smoking, alcohol, and recreational drugs • Avoid douches, vaginal sprays, scented tampons, or other feminine products that change the pH of the vagina and disturb vaginal microecology. If you are using the liquid extract, the typical dosage is 2 to 4 ml (1/2 to 1 tsp) per day. Infertility (Male) • Inability to conceive a child after six months of unprotected sex at least twice weekly with the same partner in the absence of female causes • A total sperm count lower than 5 million/ml • The presence of greater than 50% abnormal sperm • Inability of sperm to impregnate egg, as determined by the postcoital or hamster-egg penetration tests Infertility affects about 7. It is estimated that one in seven couples in the United States experiences infertility. Current estimates suggest that about 6% of men between the ages of 15 and 50 years are infertile. Although it takes only one sperm to fertilize an egg, there are nearly 200 million sperm in an average ejaculation. However, because of the natural barriers in the female reproductive tract, only about 40 sperm will ever reach the vicinity of an egg. There is a strong correlation between fertility and the number of sperm in an ejaculation. In about 90% of the cases of low sperm count, the reason is deﬁcient sperm production. Unfortunately, in about 9 out of 10 of those cases, the cause of the decreased sperm formation cannot be identiﬁed, and the condition is labeled idiopathic oligospermia (low sperm count) or azoospermia (a complete absence of living sperm). Causes of Male Infertility Deficient sperm production Ductal obstruction Congenital defects Postinfectious obstruction Cystic fibrosis Vasectomy Ejaculatory dysfunction Premature ejaculation Retrograde ejaculation Disorders of accessory glands Infection Inflammation Antisperm antibodies Coital disorders Defects in technique Premature withdrawal Erectile dysfunction Since the overwhelming majority of men who are infertile suffer from deﬁcient sperm production, that is the major focus of this chapter. Normal sperm are deﬁned as having the following characteristics: Anatomy of the Male Sexual System • A smooth, oval-shaped head that is 5 to 6 micrometers long and 2. Total sperm count and sperm quality have been deteriorating over the last few decades. In 1940, the average sperm count was 113 million/ml; in 1990, that value had dropped to 66 million/ml; and it is now holding steady at around 60 million/ml. Adding to this problem, the amount of semen in an ejaculation fell almost 20%, from 3. All together, these changes mean that men are now supplying about 40% of the number of sperm per ejaculation compared with 1940 levels. The downward trend in sperm count has led to speculation that environmental, dietary, and/or lifestyle changes in recent decades may be interfering with men’s ability to manufacture sperm. Possible Causes of Falling Sperm Count • Increased scrotal temperature • Tight-fitting clothing and briefs • Varicoceles (varicose veins that surround the testes) • Environment • Increased pollution • Heavy metals (lead, mercury, arsenic, etc. One of the key reasons these values have dropped so dramatically is that researchers are learning that quality is more important than quantity. A high sperm count means nothing if the percentage of healthy sperm is not also high. Whenever the majority of sperm are abnormally shaped or are entirely or relatively nonmotile, a man can be infertile despite having a normal sperm concentration. For example, in studies at fertility clinics, 52% of couples in which the man’s sperm count was below 10 million/ml achieved pregnancy, and 40% of couples in which the man’s sperm count was as low as 5 million/ml were able to achieve pregnancy. More sophisticated functional tests should also be used, especially in screening couples for in vitro fertilization. Causes of Temporary Low Sperm Count • Increased scrotal temperature • Infections (common cold, flu, etc. The postcoital test measures the ability of the sperm to penetrate the cervical mucus after intercourse. One of the most encouraging tests is based on the discovery that human sperm, under appropriate conditions, can penetrate hamster eggs. It has been established that fertile men exhibit a range of penetration between 10 and 100%, and that a penetration rate of less than 10% is indicative of infertility. The hamster-egg penetration test is considered to predict fertility in 66% of cases, compared with about 30% for conventional semen analysis. When produced by the man, these antibodies usually attack the tail of the sperm, thereby impeding the sperm’s ability to move and penetrate the cervical mucus. In contrast, the antisperm antibodies produced by women are typically directed against the head of the sperm. The presence of antisperm antibodies in semen analysis is usually a sign of past or current infection in the male reproductive tract. Anatomy of Sperm Therapeutic Considerations The ﬁst step in improving sperm counts, morphology, and function is controlling factors that can damage or impair their formation. Scrotal Temperature The scrotal sac normally keeps the testes at a temperature of between 94 and 96°F. Typically, the average scrotal temperature of infertile men is signiﬁcantly higher than that of fertile men. This temperature reduction is best accomplished by not wearing tight-fitting underwear or tight jeans and avoiding hot tubs. Scrotal temperature can be raised by jogging or the use of rowing machines, simulated cross- country ski machines, or treadmills, especially if a man is wearing synthetic fabrics, tight shorts, or tight underwear. After exercising, a man should allow his testicles to hang free to allow them to recover from heat buildup. Infertile men should wear boxer-type underwear and periodically take a cold shower or apply ice to the scrotum. They can also choose to use a testicular hypothermia device (also called a testicle cooler) to reduce scrotal temperatures. Still in a primitive stage, the testicle cooler looks like a jock strap from which long, thin tubes extend. The tubes are attached to a small ﬂuid reservoir ﬁlled with cold water that attaches to a belt around the waist. When the water reaches the surface of the scrotum, it evaporates and keeps the scrotum cool. Infections Infections of the male genitourinary tract, including infections of the epididymis, seminal vesicles, prostate, bladder, and urethra, are thought to play a major role in many cases of infertility. If there are no other clinical ﬁndings, antisperm antibodies or high levels of debris in a semen sample are considered good indicators of a chronic infection. There are a large number of bacteria, viruses, and other organisms that can infect the male genitourinary system. It is beyond the scope of this chapter to discuss every type of infection, so the discussion will be limited to Chlamydia trachomatis. Chlamydia is now recognized as the most common and the most serious of the infections in the male genitourinary tract. In women, chlamydia infection can lead to pelvic inﬂammatory disease and scarring of the fallopian tubes. Previous chlamydia infection accounts for a large number of cases of female-factor infertility. Typically, the symptoms will be pain or burning sensations upon urination or ejaculation. The resultant damage to these organs parallels tubal damage in women: serious scarring and blockage can occur. Unfortunately, because chlamydia lives within human cells, it may be difﬁcult to totally eradicate the organism with antibiotics alone. While acute chlamydial infections are usually associated with severe pain, chronic infections of the urethra, seminal vesicles, or prostate can occur with few or no symptoms. It is estimated that 28 to 71% of infertile men show evidence of a chlamydial infection. Because of the possible link between chlamydia and low sperm counts, there have been several double-blind studies of the effects of antibiotics on sperm counts. These studies have shown only limited improvements in sperm count and sperm quality. However, there have been isolated cases of tremendous increases in sperm counts and sperm quality after antibiotic treatment.
Regarding the value of the cuff-leak test for predicting reintubation buy propranolol 40mg low cost, only three of the 11 studies evaluated this variable buy generic propranolol 40mg. According to the results buy 40 mg propranolol with amex, this test has low accuracy to predict reintubation secondary to upper airway obstruction buy discount propranolol 80mg on-line. According to the different pub- lished series, mortality in reintubated patients ranges between 10% and 43% (compared with a rate of 2. Many studies have tried to elucidate whether this increased mortality rate is secondary to reintubation per se or to the underlying cause of reintubation. Two studies [17, 34] demonstrated that cause and timing of reintubation are associated with mortality rate. Therefore, patients who de- velop upper airway obstruction and require reintubation have a lower mortality rate than patients who are reintubated for other causes. This association was further proven by the same group  in a case–control study. In their study, 33 of the 43 patients participating had underlying chronic respiratory diseases, and it was only in those patients that the signi¿cant differences were observed. Nevertheless, the evidence is insuf¿cient, and the review involved only 171 patients. Another potential bias is that mortality rates of the control groups were con- siderably higher in comparison with other mechanical ventilation studies. Hence, more trials with a higher power are needed to evaluate net clinical bene¿ts. The results raised by two randomised clinical trials [43, 44] were quite disappointing, showing no bene¿ts for avoiding reintubation. No signi¿cant differences in reintubation rate and length of hospital stay were found. The patients were randomly assigned to receive either standard oxygen-based therapy or noninvasive bilevel positive pressure ventilation. Nava and colleagues  performed a multicentre, randomised controlled trial in 97 patients electively extubated and considered at risk of developing postextubation respi- ratory failure: patients with hypercapnia, congestive heart failure, ineffective cough and excessive secretions, more than one failed weaning trial, more than one comorbid condi- tion or upper-airway obstruction. Patients were randomly assigned to receive either noninvasive ventilation or standard oxygen over the next 24 h. Nev- ertheless, the characteristics of the control group were quite different to what was ex- pected in terms of mortality rates, tracheotomies, etc. Nevertheless, in these studies, the criteria to con- sider a patient at high risk of reintubation are chosen by the researchers and have not been properly validated, nor has their sensitivity to predict reintubation been assessed. Therefore, over the past 10 years, many efforts have been made to reduce the use of these medications in order to improve patients’ outcomes. Kollef and colleagues  performed a prospective observational study to evaluate the inÀuence of analgesics and sedatives on the overall outcomes of critically ill patients. The study involved 242 mechanically ventilated patients, of whom some received continuous sedation i. The duration of mechanical ventilation was longer among pa- tients with continuous i. In a multiple linear regression analysis adjusted for potential confounders, the adjusted duration of mechanical ventila- tion was longer in patients sedated with continuous i. In the light of these results, during the last decade, efforts have been made to evaluate and implement strategies characterised by reducing sedation or not using these agents at all in an attempt to shorten the duration of mechanical ventilation. In this context, many alter- native sedation methods have been developed to achieve safe management of the patients’ pain and anxiety, as well as to reduce the deleterious effects of oversedation, particularly a slower withdrawal from mechanical ventilation. These strategies include intermittent therapy, protocols or algorithms with de¿ned endpoints to titrate sedatives, use of medica- tions with a shorter half-life or even no sedation at all. In the in- tervention group, sedation was interrupted each morning until the patient was capable of following three to four simple commands or until he or she became agitated. In the control group, infusions were only interrupted at the discre- tion of the clinician. In a follow-up study , the researchers evaluated the possible adverse psychological effects attributable to daily sedation interruption and found it actually reduced symptoms of post- traumatic stress disorder and had no adverse psychological effects. Patients in the intervention group had signi¿cantly higher ventilator-free days (14. The study con¿rmed the bene¿t of the strategy raised previously by Kress and colleagues . Pa- tients in the intervention group had more ventilator-free days, with a mean difference after correcting for baseline variables of 4. Another approach to manage sedation in order to improve overall outcomes of me- chanically ventilated patients is the establishment of patient-targeted sedation protocols. Several trials have evaluated the effect of using these protocols/algorithms, some of which are nurse driven [54–57], showing a bene¿t in weaning outcomes. Therefore, we include a few words about the process of weaning in these special groups. These ¿ndings were con¿rmed in a study conducted by De Jonghe and colleagues  in a prospective cohort of 95 patients. Nevertheless, controversy has been raised around the threshold of mental status actually required for successful weaning. The absence of adequate mental status actually prolongs mechanical ventilation among this population. Several studies have assessed whether a systematic approach to weaning in these patients is better than using physician judgment alone. In the intervention group, a systematic approach to weaning and extubation was used, whereas in the control group, physician’s judgment only was consid- ered. Other features that must be considered when weaning these patients are the role of performing an early tracheotomy, and carefully assessing adequate cough and secretion amount. Several studies have demonstrated the importance of evaluating cough strength, amount of secretions and mental status to successfully wean a patient [30, 64]. In some of these patients, weaning from mechanical ventilation is particularly dif¿cult . Do the risk factors for extubation failure differ from those in a pooled mixed population? Is weaning different in patients with chronic hypercapnia compared with normocapnic patients? Should the same oxygenation threshold be used to assess readiness to start weaning among patients with chronic hypoxia? Several studies that try to solve these issues have been reviewed here; nevertheless, further evidence is necessary to answer many of these questions, and studies performed solely involving these subgroup of pa- tients would probably be useful for this purpose. Esteban et al (2002) Characteristics and outcomes in adult patients receiving me- chanical ventilation: a 28-day international study. Esteban et al (1994) Modes of mechanical ventilation and weaning: a national sur- vey of Spanish hospitals; the Spanish Lung Failure Collaborative Group. Brochard L, Rauss A, Benito S et al (1994) Comparison of three methods of gradual withdrawal from ventilator support during weaning from mechanical ventilation. Saura P, Blanch L, Mestre J et al (1996) Clinical consequences of the implementa- tion of a weaning protocol. Esteban A, Alía I, Gordo F et al (1997) Extubation outcome after spontaneous breathing trials with T-tube or pressure support ventilation. Ezingeard E, Diconne E, Guyomarc’h S et al (2006) Weaning from mechanical ventilation with pressure support in patients failing a T-tube trial of spontaneous breathing. Task Force by the American College of Chest Physicians; American Association for Respiratory Care and the American College of Critical Care Medicine (2001). Salam A, Tilluckdharry L, Amoateng-Adjepong Y,et al (2004) Neurologic status, cough, secretions and extubation outcomes. Nava S, Ambrosino N, Clini E et al (1998) Noninvasive mechanical ventilation in the weaning of patients with respiratory failure due to chronic obstructive pulmo- nary disease. Girault C, Daudenthun I, Chevron V et al (1999) Noninvasive ventilation as a sys- tematic extubation and weaning technique in acute-on-chronic respiratory failure. Ferrer M, Esquinas A, Arancibia F et al (2003) Noninvasive ventilation during persistent weaning failure. Research Group in Mechanical Ventilation Weaning (2008) Noninvasive mechanical ventilation may be useful in treating patients who fail weaning from invasive mechanical ventilation: a randomized controlled trial.