An 82-year-old may be robust, exercise regularly, and tolerate ten medications without any problems. A 72-year-old may be frail, take a long time to recover from an infection, and fall at night. Both have the same chronological age listed in their medical records. However, their biological resilience is completely different.
This explains why the conventional ASA score (American Society of Anesthesiologists score) often underestimates risks in older adults. It assesses underlying medical conditions—not physiological reserve. More modern risk scores (NSQIP, POSSUM, and dedicated geriatric frailty scores) have significantly better prognostic value in the over-70 age group.
→ We explain what frailty means and how it is measured in the article “Frailty Syndrome.”
Four complications dominate the picture following surgery in older adults. Each is relevant, and each is at least partially preventable.
1. Postoperative delirium (POD)
Postoperative delirium is the most common neuropsychiatric complication in older surgical patients. Its prevalence varies widely:
- After elective procedures: 10 to 20 percent
- After hip fracture surgery: 30 to 50 percent
- In intensive care units following cardiac surgery: 50 to 80 percent
Delirium is not a harmless temporary condition. It prolongs the hospital stay by an average of five to ten days, increases mortality, and doubles the risk of developing dementia in later life.
→ For more details: Delirium in Older Adults — Recognition and Treatment. And on prevention: Delirium Prevention.
2. Postoperative Cognitive Dysfunction (POCD)
Unlike delirium, POCD is a gradual, long-lasting decline in cognitive function that can persist for weeks to months after surgery. Its prevalence is 20 to 30 percent following major surgery and remains at about 10 percent after three months. The exact mechanisms are the subject of intensive research—inflammation, blood pressure fluctuations, postoperative delirium, and anesthetics all play a role. The risk is increased in patients with pre-existing mild cognitive impairment (MCI).
3. Functional Decline
The underestimated but prognostically crucial factor. Approximately 30 to 60 percent of older patients leave the hospital with a worse functional status than they had upon admission. One-third do not fully return to their baseline level. This is the path from independent living to a nursing home—often triggered by a surgery that went perfectly from a surgical standpoint. Early geriatric rehabilitation can specifically counteract this decline. Concomitant immobility in older adults should also be addressed early on.
4. Complications and Increased Mortality
Pneumonia in older adults, thrombosis, wound healing disorders, and kidney failure—these classic surgical complications occur more frequently in older patients and tend to have more severe outcomes. The 30-day mortality rate following major surgery increases significantly with age, but depends far more on frailty status than on chronological age.
The Comprehensive Geriatric Assessment (CGA) prior to surgery is a structured process used to evaluate an individual’s resilience and plan targeted optimization. It typically takes 60 to 90 minutes and covers seven dimensions:
- Functional status: Barthel Index, Timed Up and Go test, handgrip strength measurement.
- Frailty assessment: Clinical Frailty Scale or Fried phenotype. A frailty screening is also recommended.
- Cognition: MMSE or MoCA to assess dementia risk and susceptibility to postoperative depression (POD).
- Mood: Geriatric Depression Scale (GDS)—depression in older adults is an independent risk factor for postoperative complications.
- Nutritional status: Mini Nutritional Assessment (MNA). Malnutrition in older adults prior to surgery significantly increases the risk of infection and impaired wound healing.
- Medication review: According to PRISCUS and FORTA—with particular attention to substances that carry a risk of bleeding, have the potential to cause delirium, or may interact problematically with anesthetics. Keyword: deprescribing.
- Social Environment: Who will support the patient after discharge? What kind of follow-up care can be arranged?
→ How a comprehensive geriatric assessment is conducted in detail: Geriatric Assessment.
Prehabilitation is perhaps one of the most important advances in perioperative medicine in recent years. The basic idea: The weeks leading up to a planned procedure are not a waiting period, but rather the optimal window for therapy. What is built up during this time pays off many times over postoperatively.
The Core Components
- Progressive strength and endurance training: Two to four weeks of targeted training can substantially shorten the postoperative recovery period—especially important in cases of pre-existing sarcopenia.
- Nutritional optimization: Protein intake of 1.2 to 1.5 g per kg of body weight. For malnutrition in older adults, nutritional supplements and nutritional therapy support.
- Medication optimization: Discontinuing or switching potentially unsuitable medications—especially valuable time before elective surgeries. More on deprescribing.
- Smoking cessation: Even four weeks of being smoke-free before surgery significantly reduces wound healing complications.
- Optimizing underlying conditions: Diabetes in older adults, heart failure in older adults, COPD—stabilizing these conditions before surgery reduces the risk of complications.
- Psychological preparation: Informed consent is more important than simply signing a form. Patients who understand what is happening experience less anxiety and fewer episodes of delirium.
Randomized trials on prehabilitation before colorectal surgery, hip replacement, and cardiac surgery show consistent results: shorter hospital stays, fewer complications, and a faster return to independence. Investing four to six weeks in prehabilitation before an elective procedure is one of the rare, clearly evidence-based recommendations in perioperative medicine.
The modern preoperative consultation is never a monologue. It is an interdisciplinary discussion in which three professional perspectives come together:
- The surgeon: assesses the procedure—technical feasibility, type and scope, urgency, and expected benefits.
- The anesthesiologist: assesses the immediate anesthesia and intraoperative risks.
- The geriatrician: assesses the patient’s overall resilience, expected recovery, and potential for preoperative optimization. This assessment is grounded in the field of geriatrics.
In orthopedic and general surgery departments that collaborate systematically with geriatric medicine, measurable differences are evident: lower rates of delirium, shorter hospital stays, and higher rates of return to independent living. This applies in particular to hip replacement and proximal femur fractures—a core area of geriatric traumatology.
→ Specifically regarding hip replacements in older patients: Total hip replacement (THR) for patients aged 80 and older and geriatric co-management.
→ On knee replacement in older adults: Knee replacement—what older patients should know.
→ On orthopedic joint replacement in general: Joint Replacement in Older Adults.
The honest answer to an uncomfortable question: Not every technically feasible surgery is clinically advisable. In cases of severe frailty, advanced dementia in older adults, or very limited life expectancy, the harm caused by surgery may outweigh the benefits—even if the diagnosis would justify it.
Geriatrics plays a specific role here: It helps clarify treatment goals before technical decisions are made. “What is important to you when you imagine the rest of your life?” is not a philosophical question. It is the clinical anchor for any honest decision-making process. A living will drawn up in a timely manner can provide important guidance in this regard. In addition, early involvement of palliative care for the elderly is recommended.
???? For any planned major surgery involving an elderly family member: Actively request a preoperative geriatric assessment. This is not a luxury; it is the standard of modern geriatric medicine—even if it is not yet systematically offered in many hospitals.
At what age does surgery become too risky?
It is not chronological age that matters, but rather the patient’s frailty status and individual resilience. A robust 85-year-old can recover well from hip surgery, while a frail 72-year-old has a significantly higher risk of complications. The Clinical Frailty Scale and the preoperative geriatric assessment provide better answers than age alone.
What is the difference between delirium and dementia after surgery?
Delirium is an acute state of confusion—usually occurring in the first few days after surgery, with a fluctuating course, and in most cases reversible. Dementia in older adults develops over months to years and is irreversible. However, postoperative delirium can increase the risk of developing dementia later on—this is one of the reasons why delirium prevention is not a minor concern.
How long before surgery should prehabilitation begin?
Ideally, four to six weeks before the scheduled procedure. Even two weeks of structured preparation have been shown in studies to yield significant benefits. Prehabilitation includes exercise, dietary optimization, medication review, smoking cessation, and, if necessary, treatment of underlying conditions that have not yet been optimized, such as osteoporosis in older adults or polypharmacy.
As a family member, can I request a geriatric assessment?
Yes. Actively speak with the surgeon or anesthesiologist and ask for a geriatric co-evaluation before a planned major surgery. In many hospitals, this is already part of the standard process for patients over 75—in others, it must be explicitly requested. You have the right to this assessment.
Which medications should be discontinued before surgery?
The treatment team decides this on a case-by-case basis—benzodiazepines, certain antidepressants, and anticholinergic drugs should be tapered off beforehand if possible. Anticoagulants are paused according to specific protocols. Diabetes and blood pressure medications are often adjusted on the day of surgery. Never stop taking medications on your own—this can be more dangerous than continuing them. More on this: Deprescribing.
