Surgery in Elderly People

Hypertension. How best to control blood pressure around the time of surgery is controversial. Patients with longstanding hypertension may be relatively hypotensive and have low organ perfusion pressures, which would otherwise be considered tolerable by younger patients without hypertension. Additionally, antihypertensive and antianginal drugs such as beta-blockers and calcium channel blockers may not allow a patient to respond appropriately to hypotension and hypovolemia (dehydration), putting them at greater risk of inadequate tissue/organ perfusion.

Common causes of perioperotive hypotension include:

• • Hypovolemia. The most common causes of postoperative hypotension are inadequate replacement of intraoperative fluid loss, surgical hemorrhage, or third-space losses (i.e., peritoneal or pleural cavities).
• • Sepsis. This complication may occur following abdominal surgery (e.g., intra-abdominal sepsis), burns, wound infection, pneumonia, or urinary tract infections.
• • Low Cardiac Output. Many frail elderly patients have limited cardiac reserves and are extremely sensitive to small changes in intravascular volume status. Before surgery, congestive heart failure and myocardial ischemia should be ruled out in patients who have unrevascularized coronary artery disease or known heart failure problems.
• • Polypharmacy. Most older adults are on at least one drug preoperatively. Opiates. anti-cholinergics (e.g., antinausea medications) and sedation agents can depress myocardial function.

Renal dysfunction. Kidney function is reliably shown to decrease with age, increasing the risk of renal dysfunction (kidney failure) after surgery. This can be exacerbated by inappropriate fluid administration following a surgical procedure, by the toxic effect of medications used (e.g., NSAIDS, certain antibiotics) or by poor or incomplete bladder emptying due to an anatomical obstruction (e.g., large prostate, blocked urinary catheter tube), or autonomic failure. Drug administration must also account for a reduced clearance due to this reduced renal capacity, and dosages need to be adjusted accordingly.

Complications due to mobility and nutritional problems. Older adults whose mobility is compromised are more prone to complications seen with immobility at any age. They are more likely to suffer from lung microcollapse (atelectasis), which also predisposes them to pneumonia. Similarly, they are more likely to develop blood clots in the legs (deep vein thrombosis) that can break off and travel (embolize) to the lung. This potentially serious complication can aggravate hypoxia and myocardial stress, and can be fatal in some cases.

Nutritional deficiencies that either existed preoperatively or develop after surgery can significantly impact recovery by impairing wound healing, preventing adequate mobilization, and through pressure-sore development. Aggressive nutritional support should be implemented early in malnourished patients, in those with significant complications or infection (e.g., sepsis), and in those who have lost more than 10 percent of their pre-illness body weight.

Decreased mobility predisposes patients to develop pressure sores, in which the skin overlying bony surfaces breaks down and ulcerates. In some cases these can be quite extensive and require debridement and reconstructive repair. In the majority of cases these actions can be avoided through vigilant nursing care, adequate nutrition, and early mobilization and/or physical therapy.