ANESTHETIC MANAGEMENT
Data suggest that preoperative comorbid disease is a greater determinant
of postoperative complications than anesthetic management is.[154]
Thus, perioperative care should be tailored to comorbid disease and the requirements
of the surgical procedure. However, several comments concerning pharmacologic and
physiologic management are in order. Shorter-acting anesthetic agents may have a
role in caring for the elderly. For instance, a more predictable method of opioid
titration may be to use some of the shorter-acting opioids such as remifentanil.
By adjusting the bolus and infusion doses, the variability in remifentanil pharmacokinetics
is considerably less than for other intravenous opioids.[155]
Similarly, it may be prudent to use shorter-acting muscle relaxants. Studies show
an increased incidence of residual block, as well as pulmonary complications, in
patients receiving pancuronium than in those receiving atracurium or vecuronium.
[156]
When comparing inhaled anesthetics, there
does not appear to be a significant difference in the recovery profile of cognitive
function. However, desflurane is associated with the most rapid emergence.[157]
In general, it is unclear what constitutes the optimal physiologic
management to produce the best surgical outcomes. For example, what is optimal blood
pressure during surgery? This issue has been addressed during cardiopulmonary bypass,
where the question concerning the most favorable perfusion pressure remains unresolved.
[158]
[159]
Similarly,
it is uncertain whether deliberate hypotension in the elderly is detrimental. Yet
studies have demonstrated that elderly patients can safely receive controlled hypotensive
anesthesia (mean arterial blood pressure range of 45 to 55 mm Hg) during orthopedic
procedures without increased risk.[160]
Even more
controversy surrounds the question of whether better outcomes are achieved when invasive
hemodynamic monitoring is used to optimize hemodynamics and fluid therapy. The use
of pulmonary artery catheters in high-risk patients has been called into question
because large prospective randomized studies analyzing in-hospital mortality have
found no benefit for therapy directed by pulmonary artery catheter over standard
care in elderly, high-risk surgical patients requiring intensive care.[161]
Given the aforementioned evidence, optimal physiologic management of geriatric surgical
patients is still undergoing development.
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