By J. Hauke. Western Kentucky University. 2019.
Unlike most other colloids order starlix 120mg on-line, albumin is negatively charged buy starlix 120mg low cost, which causes it to be repelled by similarly negatively-charged sialoproteins in glomerular capillaries generic 120mg starlix, resulting in renal preservation of albumin. Thus, although albumin as a molecule is small enough (just) to be renally removed, glomerular filtrate albumin concentration is only 0. In health, 80 per cent of exogenous albumin remains intravascularly, expanding the blood volume for about 24 hours (Forbes 1997); however, sepsis may limit this effect to little more than an hour. Other benefits to albumin have been claimed: some anecdotal reports suggest it scavenges free radicals (so countering micropathophysiological mechanisms of critical illness). Cochrane Injuries Group Albumin Reviewers’ (1998) meta-analysis suggested albumin infusion increased mortality; predictably, this initiated heated debate, with accusations of faulted methodology. Other blood products Most blood components are available individually for transfusion, but, except for albumin, these mainly carry potential for antigen-antibody reaction and virus infection and so are subject to similar crossmatching safeguards to blood transfusion, and are not given unless specifically indicated. Like most fluids, gelatins are iso-osmotic, only expanding blood by the volume infused. Both ® of these gelatins contain high concentrations of sodium (Haemaccel 145 mmol/l, ® Gelofusin 154 mmol/l (Gosling 1999)) and so may precipitate heart failure. Dextran Dextran 40 and Dextran 70 (numbers referring to molecular weight), which are made from modified sugars, have largely fallen into disuse. They inhibit platelet aggregation and so are used to reduce perioperative risk of deep vein thromboses. Prolonged plasma expansion (the main indication for their use) necessitates continued cardiovascular monitoring. This effect can be useful to treat ischaemia and injury from intracranial oedema (Schell et al. Adverse effects of most starches include: ® ■ anaphylactic reactions with Hespan (Twigley & Hillman 1985) ■ extravasation causing gross oedema from prolonged intravascular osmotic pressure ■ coagulopathies ■ hypervolaemia from overinfusion (most units limit to one litre per patient per day) ■ circulatory overload in patients with impaired ventricular function Expense (relative to other artificial colloids) also discourages use. Fluids 331 Oxygen-carrying fluids Current plasma expanders increase blood volume without oxygen-carrying capacity resulting in dilutional anaemia; blood transfusion carries risks of viral infection, while supplies and shelf-life are limited. There are two types of oxygen-carrying fluids: ■ haemoglobin derivatives (modified human/other haemoglobin; neo-red cells) ■ chemical (e. Implications for practice ■ the prescription of fluids remains a medical decision, but nurses are professionally responsible and accountable for all fluids they administer (so should be aware of efficacy and adverse effects) and their choice of route (e. Crystalloid fluids are useful for cellular hydration, but for significant increase of intravascular volume colloids should be used. Blood and blood products are usually essential if specific components are needed, but most carry potential risks of viral transmission. Gelatins are useful both for their relative cheapness and stability, but have the shortest half-life of all colloids and so are of limited use for critically ill patients. Starch solutions have the heaviest molecular weight of all colloids, and are clinically the most useful fluids for volume replacement, but expense and side effects limit their use. Further reading Most textbooks include chapters on colloids and/or fluid replacement; Webb’s (1997) article also provides a useful overview. Separate articles, such as those cited above, can be found on each fluid, although vested interests (e. Clinical scenario Rosemary Davies, a 34-year-old accountant with no previous medical history, was found unconscious and incontinent by her friends. She had been recovering from flu, and complaining of fever, thirst, tiredness and feeling confused. Identify signs associated with dehydration for each of the three fluid compartments, (e. Q2 Select and give the rationale for the type of fluid replacement needed to correct Rosemary’s hypovolaemia and hypotension (e. Chapter 34 Inotropes Fundamental knowledge Renal anatomy: afferent arteriole, juxtaglomerular apparatus Sympathetic nervous system Negative feedback and parasympathetic effect Renin-angiotensin-aldosterone mechanism Introduction ‘Inotrope’ derives from the Greek word for ‘fibre’, and so inotropes alter the stretch of cardiac and other (smooth) muscle fibres. This effect is mediated through stimulation of the sympathetic nervous system, and can be affected positively (i. Positive inotropes, used to resolve hypotension from cardiac failure, are often assumed to primarily affect cardiac muscle fibres; while many do, some also affect muscle fibres (and so tone) in peripheral vasculature, thereby increasing systemic vascular resistance. Remembering that and then Provided other factors remain constant, increasing heart rate, stroke volume or systemic vascular resistance necessarily increases blood pressure. Inotropes increase systemic blood pressure by increasing stroke volume (myocardial stretch) and/or systemic vascular resistance (vasoconstriction). The inclusion of digoxin in both groups illustrates Inotropes 335 how artificial the division between inotropes and chronotropes can be. Digoxin is primarily a chronotrope with inotropic effects; similarly, most positive inotropes cause tachycardia. Positive inotropes may be divided into two main groups: ■ adrenergic agonists ■ phosphodiesterase inhibitors Adrenergic agonists (adrenal stimulants), or ‘catecholamines’ (adrenaline, noradrenaline) are produced in the adrenal medulla and stimulate receptors in myocardium and vascular muscles. The enzyme phosphodiesterase is negatively inotropic, and so phosphodiesterase inhibitors (e. Receptors Cardiovascular receptors influence the sympathetic/parasympathetic control (feedback). For this chapter, receptors may be divided into three groups: ■ alpha ■ beta ■ dopamine Each group can be further subdivided. Alpha receptors are primarily found in artery/arteriole smooth muscle; alpha stimulation (e. Visceral vasculature is especially susceptible to alpha stimulation, potentially causing major adverse effects: ■ heart (dysrhythmias, ischaemia, infarction) ■ liver (accentuating immunocompromise and coagulopathies) ■ kidneys (renal failure) ■ gut (translocation of gut bacteria) ■ skin (peripheral blanching or cyanosis; extreme ischaemia may precipitate gangrene, necessitating amputation of digits) Restoring central perfusion may necessitate such extreme adverse effects, but careful monitoring and observation may enable prevention of some of these. Observations include visual observation of peripheral blanching and cyanosis, and peripheral temperature (feeling hands and feet for warmth; monitoring with temperature probes). Monitoring will usually include cardiac output studies to measure systemic vascular resistance, and titrating alpha stimulants to prescribed parameters. Alpha stimulants inhibit insulin release (Moss & Craigo 1994), predisposing to hyperglycaemia. Beta1 Intensive care nursing 336 stimulation increases cell membrane permeability, thus increasing spontaneous muscle depolarisation. The effects of β 1 stimulation include (Moss & Craigo 1994): ■ increased contractility ■ improved atrioventricular conduction ■ quicker relaxation of myocardium ■ increased stroke volume ■ increased heart rate (with potential dysrhythmias) ■ therefore net increased cardiac output ■ increased release of insulin, renin and antidiuretic hormone (Moss & Craigo 1994) ■ transient hyperkalaemia: as potassium moves out from hepatic cells ■ followed by prolonged hypokalaemia as potassium moves into blood and muscle cells Beta2 receptors are found mainly in bronchial smooth muscle, but a significant minority are also found in myocardium (15 per cent of ventricle and 30–40 per cent of atrial beta receptors (Moss & Craigo 1994)).
Airborne bacteria can also be transmitted through ■ dust ■ airborne skin scales ■ droplets (e buy 120 mg starlix otc. Taylor’s (1978) classic study of nurses’ handwashing techniques identified poor technique by qualified staff; student nurses fared better buy starlix 120mg with visa, possibly due to recent education or anxieties about their clinical assessment cheap starlix 120 mg fast delivery. Poor handwashing technique may be improved through continuing (in-service) education (Gould & Chamberlain 1994) and feedback (Mayer et al. Intensive care nursing 132 Taylor also found that while palms of hands were effectively cleaned when handwashing, thumbs, tips of fingers and backs of hands were poorly washed. Fingertips, the most likely part to touch patients, may harbour bacteria unless consciously washed— observing almost anyone washing their hands (in or outside hospital) supports Taylor’s observation. Hands should be dried thoroughly after washing; wet hands (and wet alcohol) provide ideal warm, moist environments for bacterial growth. Recontamination after handwashing can be reduced by ■ elbow-operated taps ■ disposable towels (not trailing in water) ■ foot-operated pedal bins. These should be accessible and maintained (tap levers blocked by other wall fittings, empty towel dispensers or broken pedal bins are counterproductive). Chlorhexidine causes a greater reduction in skin surface bacteria than soap (Doebbling et al. Alcohol rubs are as effective as handwashing, provided the alcohol is allowed to dry (Heinz & Yakovich 1988). Gowns/aprons reduce transmission of bacteria carried on staff clothing, while reminding staff to wash their hands (associations with ‘gowning up’) and discouraging unnecessary staff from visiting bed areas. Some units adopt colour codes for each bedspace; by limiting staff having direct patient contact to those wearing the apron colour for the bedspace ensures that staff change aprons (and wash hands) between patients. Inadequate hospital laundry supply or turnover and limited changing facilities at work encourages staff to wash uniforms at home. Hospital laundry washes of 71°C kill most microorganisms (Wilson 1997) (although not necessarily hepatitis B); while uniforms should withstand such temperatures, most casual clothing will not (see labels on clothing). Home washes are usually considerably cooler and domestic washing therefore seldom sterilises clothes. Staff from other areas in direct contact with patients should be encouraged to either change into unit clothing, or remove jackets and coats worn outside the unit (before washing their hands). Critical illness necessitates contact with many staff, but unnecessary staff should be discouraged from visiting, and movement of staff between beds minimised. Conflicts with educational Infection control 133 needs (particularly in teaching hospitals) need to be evaluated against risks to patients. Communication and teamwork between different multidisciplinary team members, including microbiologists and infection control teams, can proactively minimise infection risk; multidisciplinary audit should identify unit-specific issues; action research may develop solutions. Inadequate staffing (quantity and quality) increases cross-infection (Hanson & Elston 1990). Many invasive procedures and treatments are unavoidable with critical illness, but each may introduce infection into immunocompromised patients. Nurses can usefully question whether some may be avoided: alternative routes for drugs may be possible (e. Central vein cannulae remain the major cause of nosocomial septicaemia (Randolph 1998), and so should be replaced whenever practical. Unused cannulae (peripheral or central) create unnecessary risks and should be removed. Despite extensive research, time limits for replacing invasive equipment vary between equipment type, insertion site and researchers. Hospitals and units often provide evidence-based guidelines for replacement times, and manufacturers should state recommended times; staff extending manufacturers’ times should consider their legal liability (see Chapter 45). Insertion dates of all invasive equipment should be recorded so that they can be changed promptly. Improving gut perfusion with dopamine (McClelland 1993b) has proved disappointing; dobutamine may be more effective (Levy et al. Measuring intramucosal pH (pHi) indicates sepsis and mortality (Lavery & Clapham 1993), although benefits remain controversial. Enteral nutrition (see Chapter 9) remains the most effective way to enhance gut defences and reduce translocation of gut bacteria. Intensive care nursing 134 Isolation can halve nosocomial infection rates (Hanson & Elston 1990), but increase psychological stress (see Chapter 3) and delay discharge, thus exposing patients to prolonged risk of nosocomial infection (Teare & Barrett 1997). Staff screening has recently generated heated debate in the British Medical Journal, Lessing et al. Specimen analysis incurs costs and usually requires medical approval; however vigilance by nurses often identifies signs of potential infection. Treating infection The antibiotic era has witnessed many microorganism mutations, creating resistance to successive generations of (increasingly expensive and toxic) antibiotics. Drug companies face escalating investment costs for products increasingly difficult to market, and potentially soon obsolete; Gould (1994b) reports that one-half of drug companies are stopping or seriously reducing antibiotic production. The Chief Medical Officer for Scotland has predicted that by 2020 healthcare will run out of antibiotics (cited by Amyes & Thomson 1995). Such statements may appear sensationalist, but they emphasise the need to reorientate from relying on drugs to preventing and controlling infection. Antibiotics remain useful adjuncts to treatment, but will probably become progressively less effective. The inappropriate use of antibiotics has created more pathogenic, resistant organisms (Parke & Burden 1998), and so unnecessary use is actively discouraged (House of Lords Select Committee on Science and Technology 1998). Early onset pneumonia (from aspiration during trauma) is usually antibiotic- sensitive, but late onset pneumonia (ventilator-associated pneumonia) is usually resistant (Rello et al. Monoclonal antibodies are cloned and genetically engineered human Blymphocytes (Eburn 1993). Heat Moisture Exchangers) should be changed according to manufacturers’ instructions (normally daily); catheter mounts should be changed at the same time as humidifiers Infection control 135 ■ invasive techniques and disconnection of intravenous lines should, when possible, avoid times of dust disturbance (e. Antibiotics and other medical treatments can reduce morbidity and mortality, but preventing infection is humanly (and usually financially) preferable.
Gasping for breath on these occasions starlix 120mg online, she nevertheless pushed away all who approached her to assist buy 120mg starlix with amex. Her Personal strengths: mother conﬁded that she and her husband are in the midst of a divorce and that it hasn’t been easy for Toni at home: “I know she’s been having a rough time at school buy starlix 120 mg cheap, and I guess I’ve been too caught up in my own trou- 4. Identify pertinent patient data by placing a single underline beneath the objective data in the case study and a double underline beneath the subjective data. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. For the purposes of this exercise, develop the one patient goal that demonstrates a direct resolution of the patient problem identified in the nursing diagnosis. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. For the patient with “hyperkalemia related to Circle the letter that corresponds to the best decreased renal excretion secondary to potas- answer for each question. Bowel motility will be restored within 24 + and passed to the superior vena cava just hours after beginning supplemental K. Peripherally inserted central catheter within 48 hours after removing salt substi- + tutes, coffee, tea, and other K -rich foods b. Bowel motility will be restored within mind that the electrolyte that primarily con- 24 hours after eliminating salt substitutes, trols water distribution throughout the body + coffee, tea, and other K -rich foods from is which of the following? K would you expect to be based on the effects of ﬂuid and electrolyte imbalance on human c. Pain related to surgical incision diet and drinks 3,000 mL of liquids during a 24-hour period. Altered Thought Processes related to cere- urine output for the same 24-hour period, bral edema, including mental confusion the nurse realizes that it should total approxi- and disorientation mately how many mL? Which of the following food items is a Multiple Response Questions leading source of potassium? Antecubital veins should be used for long- into entry site on bag as manufacturer term infusions. Individuals with which of the following blood before all air bubbles have disappeared. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. Which of the following are signs of complica- container, if not done by the pharmacy. A pounding headache, fainting, rapid pulse venipuncture site to obstruct venous ﬂow rate, increased blood pressure, chills, back and distend the vein. Engorged neck veins, increased blood pres- while observing and palpating for a suitable sure, and dyspnea occur when a thrombus vein. Which of the following statements accurately and have the patient lower the arm below describe the function or regulation of sodium the level of the heart to ﬁll the veins. Place the dominant hand about 4 inches deviations quickly result in serious health below the entry site to hold the skin taut problems. Sodium participates in the generation and bevel side down, at a 10- to 30-degree transmission of nerve impulses. Advance the needle or catheter into the describe the function or regulation of vein. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. The kidneys normally ﬁlter 210 L of plasma daily in the adult while excreting only 1. The cardiovascular system is responsible for pumping and carrying nutrients and water a. The regulation of the carbon dioxide level by the lungs is crucial in maintaining b. Through the process of osmosis, the solvent hormone that helps the body conserve water passes from an area of lesser solute sodium, saves chloride and water, and concentration to an area of greater solute causes potassium to be excreted. Thyroxine, released by the thyroid gland, increases blood ﬂow in the body, leading to d. A hypertonic solution has a greater concen- increased renal circulation and resulting in tration of particles in solution, causing increased glomerular ﬁltration and urinary water to move out of the cells and into the output. In the process of diffusion, the solute moves from an area of higher concentration to an Chart/Exhibit Questions area of lower concentration until equilibrium is established. Active transport is the passage of ﬂuid appearing on page 276 and circle the letter that through a permeable membrane from an corresponds to the best answer for each scenario. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. Metabolic acidosis with partial respiratory successful cardiopulmonary resuscitation a few compensation hours ago. Metabolic alkalosis with partial respiratory pensation is renal or respiratory, and partial or compensation complete. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. Substances that are dissolved in a constitutes the body’s primary buffer solution system. It participates in many important chemi- ing lymph cal reactions in the body; for example, it is necessary for many B vitamins to be 23. Measured in terms of their chemical effective and plays a role in carbohydrate combining power, or chemical activity metabolism. The difference between colloid osmotic pressure and blood hydrostatic pressure 19. A substance that prevents body ﬂuids Match the term in Part A with its deﬁnition from becoming overly acidic or alkaline listed in Part B.