Perioperative Care and Anesthesia in ME/CFS

1 Steinkirchner et al. 2026 — Perioperative Outcomes Under General Anesthesia

Full Citation:: Steinkirchner FM, Kaufmann C, Kraus RF, Kaess M, Schieffer E, Graf BM, Lassen C, Kimmerling V, Dejaco A. Perioperative outcomes in patients with myalgic encephalomyelitis/chronic fatigue syndrome undergoing general anesthesia: a retrospective matched-pair study. medRxiv. 2026. (Preprint, not yet peer-reviewed.) DOI:: 10.64898/2026.04.06.26348924 Posted:: April 7, 2026 Institution:: Department of Anaesthesiology, ME/CFS Research Group, University Hospital Regensburg, Germany Status:: Preprint — not yet peer-reviewed Study Design:: Retrospective matched-pair analysis, single tertiary centre, 2015–2026 Sample Size:: 15 ME/CFS patients matched 1:1 with controls (30 total); identified from 189 ICD-10 coded cases (G93.3, U09.9) Matching:: Sex and surgical procedure; not matched for BMI, age, or year of procedure Key Findings::

- *Intraoperative hemodynamics:* ME/CFS patients had lower lowest systolic BP (90 vs 100~mmHg, $p$=0.044) and lower lowest heart rate (50 vs 60~bpm, $p$=0.012) vs controls; however, no severe hypotension episodes, no excess vasopressor use, and no perioperative adverse events in either group — differences were statistically significant but not clinically significant
- *Postoperative pain:* Maximum NRS pain score 5.0 vs 1.0 ($p$=0.008); opioid rescue analgesia required in 80% of ME/CFS vs 33% of controls ($p$=0.039)
- *Other outcomes:* Non-opioid rescue analgesia, oxygen supplementation, postoperative nausea and vomiting, and length of PACU stay did not differ significantly

Proposed Mechanisms:: Autonomic dysfunction explains lower intraoperative hemodynamic values (lower sympathetic baseline). Central sensitization, documented in ME/CFS, is proposed as the primary mechanism underlying elevated postoperative pain burden. Critical Gap:: Post-exertional malaise — the cardinal feature of ME/CFS — was not captured. Routine perioperative documentation focuses on immediate outcomes; delayed PEM onset (24–72+ hours) means the true perioperative burden is very likely underestimated by this study design. Conclusion:: “General anesthesia appears hemodynamically well tolerated in individuals with ME/CFS. In contrast, postoperative pain burden is increased and may require tailored analgesic strategies.” Limitations::

- Small sample (n=15 pairs); substantially underpowered
- Retrospective, single-centre; limited generalizability
- Matching incomplete (not controlled for age, BMI, year of procedure)
- Large attrition from 189 identified to 15 included, likely reflecting both underdiagnosis and patient avoidance of elective procedures
- PEM not assessed: the most clinically relevant perioperative risk in ME/CFS is entirely unmeasured
- Preprint: not yet peer-reviewed

Certainty Assessment::

- *Quality:* Low (retrospective, single-centre, n=15, preprint)
- *Novelty:* High — first study to empirically examine perioperative hemodynamics in ME/CFS
- *Replication:* Not replicated; no prior literature to compare against
- *Conflicts of interest:* None declared
- *Certainty (hemodynamic safety claim):* 0.45 — directionally reassuring and mechanistically coherent, but small sample and preprint status warrant caution
- *Certainty (elevated pain burden claim):* 0.55 — large effect size ($\Delta$NRS = 4 points; OR for opioid use $\\approx$ 8.0) makes chance less plausible despite small n