By K. Rufus. Bismarck State College.

Hypotension is usually due to ■ hypovolaemia on rewarming Intensive care nursing 298 ■ myocardial dysfunction buy super p-force 160 mg online jack3d causes erectile dysfunction. Two or three drains are inserted in the following regions: ■ pericardial ■ mediastinal ■ pleural (if pleura injured) order 160 mg super p-force with mastercard impotence libido. Closed systems should be maintained, and clamps made available in case of disconnection. Drainage, usually recorded hourly, should gradually reduce, becoming more serious. Sudden cessation may indicate thrombus obstruction, with likely tamponade; if patency of drains cannot be re- established, this should be reported urgently as emergency thoracotomy may be needed. The value of milking drains is debated; they can restore patency, but large negative pressures may damage tissue (Gordon et al. Dependent loops in chest drain tubing may inhibit drainage, so although evidence is lacking, they should be avoided (Gordon et al. Cardiac surgery 299 Reversing hypothermia causes vasodilation, necessitating large volumes of fluid. Total body hydration is normally maintained with continuous low-volume crystalloid infusion (e. Fluid charts may be divided between colloids (colloidal infusions against blood loss) and crystalloids (crystalloid infusion against urine output). Blood is often transfused if haemoglobin falls below 10 g/dl (haematocrit below 33 per cent). Haemodilution with colloids usually necessitates blood supplements, and so patients should already have units crossmatched. Temperature Gradual rewarming should bring central temperature within 2°C of peripheral (pedal) temperature (avoid limbs from which saphenous veins are harvested). Use of artificial warming is controversial: it can cause burns, although recently marketed warming devices are generally safe and reliable; it hastens homeostasis and may prevent shivering (which increases metabolic rate, so increasing oxygen consumption and metabolic acidosis). Acid-base balance Anaerobic metabolism from cold cardioplegia and hypoperfusion causes metabolic acidosis so that cardiovascular instability continues during rewarming. Although acidosis is closely monitored through blood gas analysis, it is not usually necessary to treat acidosis following cardiac surgery. Dysrhythmias Various dysrhythmias (often multifocal) often occur following cardiac (especially valve) surgery. Causes include: ■ chronic cardiomyopathy ■ oedema (from surgery, disrupting conduction pathways) ■ acidosis ■ electrolyte imbalance ■ hypoxia/ischaemia ■ mechanical irritation (e. Atrial fibrillation, the most common postoperative dysrhythmia (Ellis 1998), is relatively benign. Bradycardia, blocks, functional and tachydysrhymias frequently occur; persistent blocks often require pacing, hence perioperative placement of epicardial wires. Intensive care nursing 300 Epicardial wires are unipolar, a negative pole being created by inserting a subcutaneous needle. Pacing wires usually remain in place until dysrhythmias become unlikely (normally 5–10 days). Internal defibrillation avoids transthoracic bioimpedance, so uses lower voltage (e. Causes include: ■ fluid shifts from vasoactive mediators ■ hyperkalaemia from damaged cell membranes leakage ■ hypokalaemia from forced diuresis; also cell recovery returning potassium to intracellular fluid ■ hormones (e.

Hairs in this structure are what ultimately send the signal down the auditory nerve cheap super p-force 160 mg overnight delivery erectile dysfunction losartan. These little endolymph- filled sacs have hairs and chunks of calcium carbonate that detect changes in gravitational forces discount super p-force 160 mg erectile dysfunction daily medication. Pinna Chapter 16 Raging Hormones: The Endocrine System In This Chapter Absorbing what endocrine glands do Checking out the ringmasters: Pituitary and hypothalamus glands Surveying the supporting glands Understanding how the body balances under stress he human body has two separate command and control systems that work in harmony Tmost of the time but also work in very different ways. Designed for instant response, the nervous system cracks its cellular whip using electrical signals that make entire systems hop to their tasks with no delay (refer to Chapter 15). By contrast, the endocrine system’s glands use chemical signals called hormones that behave like the steering mechanism on a large, fully loaded ocean tanker; small changes can have big impacts, but it takes quite a bit of time for any evidence of the change to make itself known. At times, parts of the nervous system stimulate or inhibit the secretion of hormones, and some hormones are capable of stimulating or inhibiting the flow of nerve impulses. The word “hormone” originates from the Greek word hormao, which literally translates as “I excite. Each chemical signal stimulates some specific part of the body, known as target tissues or target cells. The body needs a constant supply of hormonal signals to grow, maintain homeostasis, reproduce, and conduct myriad processes. In this chapter, we go over which glands do what and where, as well as review the types of chemical signals that play various roles in the body. You also get to practice discerning what the endocrine system does, how it does it, and why the body responds like it does. No Bland Glands Technically, there are ten or so primary endocrine glands with various other hormone- secreting tissues scattered throughout the body. Unlike exocrine glands (such as mammary glands and sweat glands), endocrine glands have no ducts to convey their secretions. Instead, hormones move directly into extracellular spaces surrounding the gland and from there move into capillaries and the greater bloodstream. Although they spread throughout the body in the bloodstream, hormones are uniquely tagged by their chemical composition. Thus they have separate identities and stimulate specific receptors on target cells so that usually only the intended cells or tissues respond to their signals. All of the many hormones can be classified either as steroid (derived from cholesterol) or nonsteroid (derived from amino acids and other proteins). The steroid hormones — which include testosterone, estrogen, progesterone, and cortisol — are the ones most closely Part V: Mission Control: All Systems Go 266 associated with emotional outbursts and mood swings. Steroidal hormones, which are nonpolar (see Chapter 2 for details on cell diffusion), penetrate cell membranes easily and initiate protein production at the nucleus. Nonsteroid hormones are divided among four classifications: Some are derived from modified amino acids, including such things as epineph- rine and norepinephrine, as well as melatonin. Protein-based nonsteroid hormones include such crucial substances as insulin and growth hormone as well as prolactin and parathyroid hormone. Hormone functions include controlling the body’s internal environment by regulating its chemical composition and volume, activating responses to changes in environmen- tal conditions to help the body cope, influencing growth and development, enabling several key steps in reproduction, regulating components of the immune system, and regulating organic metabolism. Glands that secrete their product into the interstitial fluid, which flows into the blood, are a.

According to the Cannon-Bard theory of emotion safe super p-force 160mg erectile dysfunction treatment by injection, the experience of an emotion is accompanied by physiological arousal quality super p-force 160 mg impotence 35 years old. Thus, according to this model of emotion, as we become aware of danger, our heart rate also increases. Although the idea that the experience of an emotion occurs alongside the accompanying arousal seems intuitive to our everyday experiences, the psychologists William James and Carl Lange had another idea about the role of arousal. According to the James-Lange theory of emotion, our experience of an emotion is the result of the arousal that we experience. This approach proposes that the arousal and the emotion are not independent, but rather that the emotion depends on the arousal. The fear does not occur along with the racing heart but occurs because of the racing heart. As William James put it, “We feel sorry because we cry, angry because we strike, afraid [6] because we tremble‖ (James, 1884, p. A fundamental aspect of the James-Lange theory is that different patterns of arousal may create different emotional experiences. The emotional circuits in the limbic system are activated when an emotional stimulus is experienced, and these circuits quickly create corresponding physical [7] reactions (LeDoux, 2000). The process happens so quickly that it may feel to us as if emotion is simultaneous with our physical arousal. On the other hand, and as predicted by the James-Lange theory, our experiences of emotion are weaker without arousal. Patients who have spinal injuries that reduce their experience of arousal [8] also report decreases in emotional responses (Hohmann, 1966). There is also at least some support for the idea that different emotions are produced by different patterns of arousal. The Two-Factor Theory of Emotion Whereas the James-Lange theory proposes that each emotion has a different pattern of arousal, the two-factor theory of emotion takes the opposite approach, arguing that the arousal that we experience is basically the same in every emotion, and that all emotions (including the basic emotions) are differentiated only by our cognitive appraisal of the source of the arousal. The two-factor theory of emotion asserts that the experience of emotion is determined by the intensity of the arousal we are experiencing, but that the cognitive appraisal of the situation determines what the emotion will be. Because both arousal and appraisal are necessary, we can say that emotions have two factors: an arousal factor and a cognitive factor (Schachter & Singer, [12] 1962): emotion = arousal + cognition In some cases it may be difficult for a person who is experiencing a high level of arousal to accurately determine which emotion she is experiencing. That is, she may be certain that she is feeling arousal, but the meaning of the arousal (the cognitive factor) may be less clear. Some romantic relationships, for instance, have a very high level of arousal, and the partners alternatively experience extreme highs and lows in the relationship. One day they are madly in love with each other and the next they are in a huge fight. In situations that are accompanied by high arousal, people may be unsure what emotion they are experiencing. In the high arousal relationship, for instance, the partners may be uncertain whether the emotion they are feeling is love, hate, or both at the same time (sound familiar? When he had finished, she wrote her name and phone number on a piece of paper, and invited him to call if he wanted to hear more about the project. More than half of the men who had been interviewed on the bridge later called the woman.