By Q. Kadok. North Georgia College and State University, the Military College of Georgia. 2018.
Medicolegally buy generic doxepin 25 mg on-line anxiety 2, the physician must disclose fully to the patient medically known risks that are posed by maternal substance abuse best 75mg doxepin anxiety symptoms getting worse. This disclosure should also be documented in the medical record in a clear and concise manner. It is extremely impor- tant that the physician emphasizes to the patient that the use of social or illicit sub- stances is totally contraindicated during the course of pregnancy. These are not theoretical concerns because we have assisted in the defense of physicians sued for adverse pregnancy outcomes caused by substance abuse, despite the physician’s appropriate counseling that the patient chose to ignore. The risk–benefit ratio for substance abuse during pregnancy is easily explained to be increased risk with no benefit. The patient consultation, particularly this aspect, must be documented in the medical record to show that the risk was recognized and patient appropriately advised. Patients have been asked to initial or sign counseling notes regarding substance abuse during pregnancy to acknowledge that they received and understood counseling. Patient consultation Pregnant women usually admit to some use of a substance, but rarely do they admit that they have a ‘problem’ with social or illicit substance. Once some substance use is admit- 298 Substance abuse during pregnancy ted, two tandem approaches to the history-taking process are suggested. Differences in substance use between weekdays and weekends are important to ascertain, because it is common for the user’s pattern of use to differ greatly between these two time periods. The patient should describe her daily activities, including any substances used, from awaken- ing to going to sleep at night on a normal weekday. The patient should be asked when she begins drinking or using drugs during the course of a day and the duration of such use. For example, does the patient use the sub- stance as an ‘eye-opener’ in the morning (Sokol et al. The patient should be asked to disclose how much of the substance is used in an average day and approximately how much would be consumed in an hour. Combined with information about the weekly pattern (weekend versus weekday), a semiquantita- tive estimate of the amount and frequency of substance use can be made. Alcohol use during pregnancy is well studied and crude risks of fetal alcohol syn- drome can actually be made by estimating the average daily dose. With other less well- researched substances used during pregnancy, daily dose information can be used only to assess the severity of maternal addiction. Very serious dependencies are, of course, associated with more severe adverse effects. At the outset, the physician should explain to the patient that the purpose of obtaining this personal and private informa- tion is to better manage the pregnancy, i. The author’s spouse is an attorney, and states that no release should ever be signed and that each person must protect their individual rights to privacy assertively. Another important aspect of patient consultation is to provide information regarding specific risks from substance use (Tables 16. The most ethical and legally sound approach is to provide information that may be verified directly with the medical litera- ture. Ultimately, the clinical conclusion/treatment is that social and illicit substance use during pregnancy is contraindicated because of the associated maternal and embryo fetal risks. The need for services to assist pregnant substance users is being recognized, and pro- grams exist in most areas. For assistance in locating such a treatment program, the physi- cian can contact their local substance abuse service, or their state’s commission on sub- stance abuse that accredits treatment facilities. Ideally, the pregnant substance user should be managed by the obstetrician in conjunction with a program designed to promote absti- nence or at least to reduce the substance use during pregnancy. The medical positions of abstinence and treatment are the only appropriate ones clinically and legally. One’s medical mal- practice insurance provider is often the most economical and efficient source of legal infor- mation as this service is often included as a provision of a medical malpractice policy. Drug injec- tion sites on the upper forearm (‘track marks’) are strong evidence of a serious substance use problem, but this is not frequently observed.
As a result buy generic doxepin 10mg on line anxiety symptoms 4 dpo, the natural frequency of the artery is signiﬁcantly decreased cheap doxepin 75mg on line anxiety nursing diagnosis, often down to a few hundred hertz. The plaque- coated artery with its lowered natural frequency may now be set into resonant vibrational motion, which may dislodge plaque deposits or cause further dam- age to the arterial wall. We will now compute the power generated by the heart to keep the blood ﬂowing in the circulatory system. Therefore, as shown in Exercise 8-10, the power output of the right ventricle is 0. While in fact the systolic blood pressure rises with increa- sed blood ﬂow, in these calculations we have assumed that it remains at 120 torr. Both abnormally high and abnormally low blood pressures indicate some disorders in the body that require medical attention. High blood pres- sure, which may be caused by constrictions in the circulatory system, certainly implies that the heart is working harder than usual and that it may be endan- gered by the excess load. Blood pressure can be measured most directly by inserting a vertical glass tube into an artery and observing the height to which the blood rises (see Fig. This was, in fact, the way blood pressure was ﬁrst measured in 1733 by Reverend Stephen Hales, who connected a long ver- tical glass tube to an artery of a horse. Although sophisticated modiﬁcations of this technique are still used in special cases, this method is obviously not satisfactory for routine clinical examinations. Routine measurements of blood pressure are now most commonly performed by the cut-oﬀ method. Although this method is not as accurate as direct measurements, it is simple and in most cases adequate. In this technique, a cuﬀ containing an inﬂatable balloon is placed tightly around the upper arm. The balloon is inﬂated with a bulb, and the pressure in the balloon is monitored by a pressure gauge. The initial pres- sure in the balloon is greater than the systolic pressure, and the ﬂow of blood through the artery is therefore cut oﬀ. The observer then allows the pressure in the balloon to fall slowly by releasing some of the air. As the pressure drops, she listens with a stethoscope placed over the artery downstream from the cuﬀ. No sound is heard until the pressure in the balloon decreases to the systolic pressure. Just below this point the blood begins to ﬂow through the artery; however, since the artery is still partially constricted, the ﬂow is turbulent and is accompanied by a characteristic sound. As the pressure in the balloon drops further, the artery expands to its normal size, the ﬂow becomes laminar, and the noise disappears. The pressure at which the sound begins to fade is taken as the diastolic pressure. The cut-oﬀ blood pressure measurement is taken with the cuﬀ placed on the arm approximately at heart level. Calculate the pressure drop per centimeter length of the aorta when the blood ﬂow rate is 25 liter/min. The radius of the aorta is about 1 cm, and the coeﬃcient of viscosity of blood is 4 × 10−2 poise. Compute the average velocity of the blood in the aorta of radius 1 cm if the ﬂow rate is 5 liter/min. When the rate of blood ﬂow in the aorta is 5 liter/min, the velocity of the blood in the capillaries is about 0. Compute the decrease in the blood pressure of the blood ﬂowing through an artery the radius of which is constricted by a factor of 3. Using information provided in the text, calculate the power generated by the left ventricle during intense physical activity when the ﬂow rate is 25 liter/min. Using information provided in the text, calculate the power generated by the right ventricle during (a) restful state; blood ﬂow 5 liter/min, and (b) intense activity; blood ﬂow 25 liter/min.
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Ideally doxepin 10mg with mastercard anxiety nursing interventions, some means should be used to measure the effectofadrug before a patient is com- mitted to long-term therapy order doxepin 75 mg on line anxiety of death. Treatmentofventricular arrhythmias 157 Holter monitoring was the only methodology available for guiding drug therapy until the late 1970s, and it was widely useduntilalmost 1990. If a reentrant circuit is present that is ca- pable of generating an arrhythmia, all youneed to do to start the arrhythmia istointroducean appropriately timed electrical impulse into the circuit (see Figure 1. The assessment is donebyadministering one of the antiarrhythmic drugsand then attempting to reinduce the arrhythmia. If a previously inducible arrhythmia isrendered noninducible by a drug, it is assumed that the drug has favorably changed the characteristics of the reentrant circuit. The rate of recurrent arrhythmias for 158 Chapter 12 both treatment groups was nearly 40% at 1 year and 66% at 4 years. Empiric drug therapy Using antiarrhythmic drugsempirically simply meansadminister- ing themwithoutan attempttomeasure their efﬁcacy beforehand. Implantable deﬁbrilla- tors were also usedinmany patients in the study, so the effectof amiodarone in reducing mortality couldnot be well evaluatedinthis trial. Sotalol, in particular, seemstoprovidesomebeneﬁt in these patients, and there Treatmentofventricular arrhythmias 159 is preliminary evidence that dofetilide, as well as the investigational drug azimilide, may also be helpful. Empiric drug therapysimply cannot be re- liedupon as the primary treatmentofchoice for patients presenting with sustained ventricular tachyarrhythmias. No other therapy is as effective in elim- inating the risk of suddendeath in this population. Patients with reduced ejec- tion fractionsand either prior myocardial infarctionsorahistory of heart failure (i. In addition, beta blockers have been shown to reduce the risk of suddendeath in both survivors of myocardial infarction and patients with heart failure, and they should be given to these patients whether they have had sustained ventricular arrhythmias or not. Treatment of less common forms of ventricular tachyarrhythmias In Chapter 1, we mentioned several less common formsofven- tricular tachyarrhythmias, noneofwhich are caused by the typical intramyocardial reentrant circuits associatedwith coronary artery disease or cardiomyopathy. Two of these are known to be dueto channelopathies—the arrhythmias caused by triggered activity, and those related to the Brugadasyndrome—and were coveredinsome detail in the discussion onchannelopathies in that chapter. Bundle branch reentry Bundle branch reentry is seen occasionally in patients with dilated cardiomyopathy and intraventricular conductiondelays. While such patients, duetothenature of their underlying heart disease, have a high propensity for “typical” reentrantventricular arrhythmias, they can also develop bundle branch reentry. In bundle branch reentry, the reentrant circuit is formed by the right and left bundle branches, the bundle of His, and the intervening ventricular myocardium. An arrhythmia can be triggeredwhen a premature ventricular impulse enters both bundle branches in the retrograde direction, is blocked in the right bundle branchbut conducts up the left bundle branch (which has a shorter refractory period)and then turns around at the bundle of Hisand reenters the right bundle branch in the ante- grade direction. Antiarrhythmic drugs have little or no role in the managementof bundle branch reentry. These arrhythmias originate, for the most part, in the outﬂow tract of the right ventricle. They are seen almost exclusively in young-to-middle-age patients, and they are exacerbated by in- creased adrenergic tone. However, since these arrhythmias are often localiz- able, they are quite amenable to radiofrequency ablation, which is reported to be completely effective in over 80% of cases. The arrhythmia is not associatedwith exercise, and symptoms are usually limited to palpitationsand light-headedness. Amiodarone in patients with con- gestive heart failure and asymptomatic ventricular arrhythmia. A comparison of electrophysiologic testing with Holter moni- toring to predictantiarrhythmic drug efﬁcacy for ventricular tachyarrhyth- mias. These physiologic stresses include the hemodynamic stress produced by a “chronic” high-output state, various hormonal shifts, and changes in auto- nomic tone. Further, womenwith congenital heart disease, evenif successfully repaired, are especially likely to develop arrhythmias if they become pregnant. Ventricular arrhythmias are relatively rare during pregnancy un- less underlying heart disease is present. Indeed, womenwho de- velop ventricular arrhythmias while pregnant should be evaluated for heart disease (including pregnancy-relatedcardiomyopathy), as well as accelerated hypertension and thyrotoxicosis. Using antiarrhythmic drugs in pregnancy There isarisk to both mother and fetus in using antiarrhythmic drugs during pregnancy, and these drugs should be avoided altogether un- less the arrhythmias are intolerable. Furthermore, it should be rec- ognized that conducting systematic, prospective clinical studies on the use of antiarrhythmic drugs in pregnant women has simply not been feasible and that, therefore, the quality of informationwe have 164 Treatment of arrhythmias in pregnancy 165 on the safety and efﬁcacy of these drugs during pregnancy isquite poor and incomplete.