Clinical overview
Figure F1.1 — Performance status is reserve versus insult: the operative outcome is the patient's physiological reserve minus the magnitude of the surgical insult, weighed against the urgency of operation.
Performance status is the single most useful summary judgement a gynaecologist makes before booking an operation: can this patient's body tolerate the physiological insult I am about to impose, and survive the recovery? It is not a number on a form. It is the synthesis of how much the patient can physically do, what reserve their heart, lungs, kidneys and brain hold against the demand of surgery, and how those reserves intersect with the operation planned. A laparoscopic sterilisation and a debulking laparotomy for advanced ovarian cancer make wholly different demands; the same frail 72-year-old may sail through one and die of the other. The substance of this judgement is not reciting the ASA classes but weighing a patient against an operation and deciding whether, when, where and by whom it should be done.
This judgement carries real weight in South Africa, where the surgical population is shaped by a young but heavily HIV-burdened demographic, late presentation of gynaecological malignancy, high rates of obesity, hypertension and undiagnosed diabetes, anaemia from chronic menorrhagia and parasitic disease, and a constrained critical-care footprint. A patient who would be admitted to a high-care bed without question in a tertiary centre may have no such bed available at a district hospital. Considering performance status therefore means considering the system as much as the patient: the level of care, the availability of blood, the anaesthetic seniority on call, and whether transfer to a referral centre is the safest "operation" of all. This chapter pairs closely with ERAS principles, Perioperative fluids and, for the cancer patient, Pregnancy and neoplasia and the obstetric crossover of High-risk pregnancy factors.
Core knowledge
What "performance status" actually means
Performance status is an umbrella for several overlapping but distinct constructs, and they are best kept separate:
- Functional capacity — what the patient can physically do, expressed as metabolic equivalents (METs). One MET is resting oxygen consumption; climbing two flights of stairs or walking up a hill is classically taken as roughly 4 METs, the conventional threshold above which perioperative cardiac risk is reassuring. Inability to achieve ~4 METs (cannot climb a flight of stairs, breathless walking on the flat) flags poor reserve and warrants closer cardiopulmonary scrutiny. Functional capacity is standard preoperative teaching and the MET threshold is a long-standing convention rather than a precise cut-point — treat it as a screen, not a verdict.
- ASA physical status — the American Society of Anesthesiologists' I–VI scale grading the systemic burden of comorbidity (see table). It predicts perioperative mortality robustly but is a clinician's gestalt, with known inter-rater variability; it does not measure organ-specific reserve.
- Oncological performance status — the ECOG (0–4) and Karnofsky (100–0) scales, used to decide fitness for chemotherapy, radical surgery and trial enrolment in gynae-oncology. These are central to deciding whether a woman with advanced ovarian or cervical cancer can withstand primary debulking or should have neoadjuvant chemotherapy first.
- Frailty — a syndrome of diminished physiological reserve across multiple systems, only loosely correlated with chronological age, increasingly recognised as a better predictor of adverse surgical outcome in the elderly than any single comorbidity. Assessed with tools such as the Clinical Frailty Scale.
ASA physical status classification
| Class | Description | Typical gynaecological example |
|---|---|---|
| ASA I | Normal healthy patient | Fit young woman for laparoscopic sterilisation |
| ASA II | Mild systemic disease, no functional limitation | Well-controlled hypertension; well-controlled HIV on ART; BMI 30–40 |
| ASA III | Severe systemic disease, functional limitation | Poorly controlled diabetes; symptomatic chronic kidney disease; BMI ≥40; stable angina |
| ASA IV | Severe systemic disease that is a constant threat to life | Recent MI/stroke, decompensated cardiac failure, sepsis with organ dysfunction |
| ASA V | Moribund, not expected to survive without the operation | Ruptured ectopic with profound shock, comatose |
| ASA VI | Brain-dead, organ procurement | — |
The suffix E is added for emergency operations (e.g. ASA IIIE), and emergency status independently raises risk because there is no time to optimise.
Why this matters physiologically
Surgery triggers a neuroendocrine and inflammatory stress response — catecholamine and cortisol surge, insulin resistance, a procoagulant shift, fluid sequestration into the "third space", and increased myocardial oxygen demand. A patient with ample reserve absorbs this; a patient near the edge of cardiac, respiratory or renal compensation is tipped into failure. Performance status is, in effect, a clinical estimate of how much of this stress response the patient can absorb. Modern enteral preparation and the ERAS philosophy exist precisely to blunt that stress response (avoiding prolonged fasting, opioid-sparing analgesia, early feeding and mobilisation), which is why optimisation and ERAS are two sides of the same coin.