Hemodynamic effects of central neural blockade in elderly patients

Abstract

I N all developed countries in the world the elderly are now recognized as an increasing segment of the population. In one century the number of persons of 65 or older has increased three times perhaps because of better and more available medical care. By 2030, up to 20% of Western populations will be more than 65 yr of age. 1 The oldest old (people aged 80 and over) are the fastest growing segment of the older population. Improvements in surgical techniques, anesthesia and intensive care units have made surgical interventions in more and more older and sicker patients possible. Over half of the population older than 65 yr will require surgical intervention at least once during the remainder of their lives and have surgery four times more often than the rest of the population. 2 Accordingly, elderly patients will become a very large part of our anesthetic practice. The most common procedures, which are performed in the elderly, involve the cardiovascular system, the digestive system and musculoskeletal system.Regional anesthetic techniques (peripheral nerve blockade, central neural blockade) are frequently used in elderly patients, especially during orthopedic surgery, genito-urological, abdominal and gynecological procedures.Systemic hypotension and bradycardia are the most common cardiovascular disturbances associated with central neural blockade, with a particularly frequent incidence in the elderly. 3 Systemic hypotension occurs from decreases in systemic vascular resistance and central venous pressure from sympathetic block with vasodilatation and redistribution of central blood volume to lower extremities and splanchnic beds. 4 Marked hypotension may be especially harmful to elderly patients with limited cardiac reserve. Besides, elderly patients have decreased physiological reserve and an increased incidence of systemic disease. Normal aging is associated with a reduction in the baroreceptor-reflex mediated heart rate response to hypotensive stimuli. 5 Consequently elderly patients may not respond with the same degree of sympathetic activity as younger patients. Decreased cardiac reserves, structural changes in the arterioles and changes in the autonomic nervous system with increasing age may also play a role.High levels of sensory anesthesia and increasing age appeared to be the two main risk factors for the development of hypotension after spinal anesthesia. 6 In elderly patients both epidural and spinal anesthesia are associated with increased levels of analgesia. [7][8][9][10][11][12] The level of analgesia increases with advancing age after lumbar epidural administration of a given dose (fixed volume and concentration) of a local anesthetic solution 7-9 and following thoracic epidural administration of a fixed dose. 11 Increased levels of analgesia with advancing age have been attributed to reduced leakage of local anesthetic solution, because of progressive sclerotic closure of intervertebral foramina. As the fatty tissue degenerates with advancing age, the epidural space becomes more compliant and ...

Haemodynamic effects of central neural blocks

“…The degree of the effect depends on the position of the patient's body, the type of surgery, the technique of anaesthesia.Severe hypotension is associated with high risk in case of advanced age, therefore the continuous spinal anaesthesia (CSA) is a well-established technique that has been used successfully in this group of patients. CSA is an effective technique in elderly patients undergoing lower extremity surgery (3,14). Imbelloni and co-workers found that the CSA technique compared with the CSE block is safer for high-risk patients with unstable haemodynamics because the injected dose of a local anaesthetic is lower, it gives better control of the level of blockade and shorter duration of arterial hypotension (14).…”

“…Usually, these haemodynamic effects could be considered as normal reactions to central neural blockade (1). However, severe hypotension may have significant outcomes in elderly patients with limited reserve and atherosclerosis, coronary artery disease (3,15). The incidence of hypotension is reported to occur from 5% to 81% depending on the definition (2, 9).…”

Effects of bupivacaine, levobupivacaine and ropivacaine on myocardial relaxation

“…To minimize such risks, and to decrease the incidence of hemodynamic instability in high risk surgical populations (the elderly, patients with ischemic heart disease and/or a history of heart failure), it has been suggested that the dose of LAAs be reduced by combining LAAs with adjuvant drugs such as sufentanil 40 or to administer LAAs continuously via spinal anesthesia. 41 The following points must be considered in the assessment of the clinical relevance of our results. First, because this study was conducted in vitro, it examined only intrinsic myocardial contractility.…”

Safety of opioid patch initiation in Australian residential aged care

“…Older patients may be more susceptible to some of the adverse effects of epidural analgesia, including hypotension (Crawford et al, 1996;Simon et al, 2002;Veering, 2006).…”