Background:
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic multisystem disease characterized by profound fatigue, post-exertional malaise, cognitive impairment, and autonomic dysfunction. Despite features with potential relevance for anesthesia and perioperative care, empirical data on perioperative outcomes in patients with ME/CFS remains limited. We therefore performed a retrospective matched-pair analysis to generate clinical data on perioperative responses and identify areas for future research.

Methods:
We conducted a retrospective matched-pair analysis at a single tertiary center. All patients with ME/CFS undergoing general anesthesia from 2015 to 2026 were identified using ICD-10-GM codes with additional manual verification and matched 1:1 to controls for comparison. Patients with confounding diagnoses or American Society of Anesthesiologists physical status above III were excluded. The analysis focused on intraoperative hemodynamic parameters, including baseline, post-induction, median, and lowest recorded systolic blood pressure and heart rate, as well as early postoperative outcomes in the post-anesthesia care unit (PACU), including maximum pain scores and requirement for rescue analgesia.

Results:
Out of 189 individuals identified through ICD-10 codes, 15 matched pairs were included after application of exclusion criteria. Patients with ME/CFS exhibited lower minimum intraoperative systolic blood pressure (90.0 [82.5–95.0] vs. 100.0 [90.0–110.0] mmHg, p = 0.044) and lower minimum heart rate (50.0 [40.0–57.5] vs. 60.0 [50.0–65.0] bpm, p = 0.012). Vasopressor use and fluid administration did not differ, and no episodes of severe hypotension or perioperative adverse events were observed. Postoperative pain was higher in ME/CFS, with higher maximum pain scores (NRS 5.0 [4.0–6.0] vs. 1.0 [0.0–4.0], p = 0.008) and more frequent opioid rescue analgesia (80% vs. 33%, p = 0.039). Postoperative nausea or vomiting, oxygen supplementation, and PACU length of stay were similar between groups.

Conclusions:
In this small exploratory cohort, general anesthesia was not associated with clinically relevant hemodynamic instability in patients with ME/CFS. Postoperative pain scores and opioid rescue requirements were higher in the ME/CFS group. Post-exertional malaise, a key disease feature with potentially delayed onset and significant impact, was not captured and remains an important target for future research. These findings should be considered hypothesis-generating and support prospective studies evaluating perioperative management and patient-relevant outcomes in ME/CFS.