Section 1
What Is the NSRI™?
The Neurologic Stress & Recovery Index™ (NSRI™) quantifies the brain’s capacity to absorb and recover from neurologic stressors — measuring reserve and recovery dynamics before injury occurs.
The NSRI™ is the first validated pre-surgical assessment tool designed to measure perioperative brain resilience. It was developed by Sandra Bargeron, PA-C, CAA — a licensed physician assistant and Certified Anesthesiologist Assistant with 22 years of clinical experience and 10,000+ anesthesia cases.
Jump to section
| Current Standard of Care | Beyond Brain Health / NSRI™ |
|---|---|
| Drug-focused outcomes | Brain-state focused outcomes |
| Post-event reaction | Pre-event measurement and optimization |
| Anesthesia as isolated neutral event | Anesthesia as neurologic stress exposure |
| Cognitive decline as acceptable trade-off | Cognitive decline as modifiable risk |
| Passive patient role | Empowered patient with personalized optimization |
| Standardized protocols for all patients | Terrain-based assessment with individualized pathways |
“Surgery doesn’t create vulnerabilities. It reveals them.”
— Sandra Bargeron, PA-C, CAA
Section 2 — Live Data
NSRI™ Population Data
⚡ Data current as of March 5, 2026. 1037 completed assessments | 1,230+ in progress | Research window closes March 12, 2026. Statistics will be updated with final dataset.
1037+
Completed Assessments
65.8
Mean Final Score (out of 100)
32.3%
Scored Low or Critical (≤60)
0.292
Mean Bottleneck Index
Score Distribution
| Score Band | Count | % of Completers | Clinical Interpretation |
|---|---|---|---|
| Critical (0–40) | 42 | 5.0% | Immediate optimization recommended |
| Low (41–60) | 228 | 27.2% | Significant optimization opportunity |
| Moderate (61–80) | 446 | 53.3% | Targeted improvements available |
| Strong (81–100) | 121 | 14.5% | Well-optimized neurologic reserve |
32.3% of completers scored in the Low or Critical range. These individuals have the highest modifiable opportunity. 45.2% carry a Bottleneck Index above 0.25 — meaning historical vulnerability is compressing their score regardless of current lifestyle factors.
Top Modifiable Vulnerabilities — Ranked by Weakness
1
Exercise Frequency (D4 Lifestyle)
38% rarely or never exercise; 9% unable to exercise
53.1%
2
Sleep Quality (D3 Sleep)
Only 9.4% report restorative sleep; 42% fragmented or poor
53.5%
3
Hydration (D4 Lifestyle)
41% drink fewer than 5 glasses per day; 15% under 3 glasses
56.2%
4
Cholesterol Management (D1 Cardiometabolic)
24.5% uncontrolled or untreated; 5.6% never tested
59.6%
5
Weight Status (D1 Cardiometabolic)
Significant overweight and obesity prevalence across cohort
65.2%
6
Daily Activity Level (D4 Lifestyle)
Many report mostly sedentary days outside structured exercise
65.8%
7
Mood & Anxiety (D5 Brain/Social)
~27% experience moderate to severe symptoms
73.1%
8
Pre-Surgical Sleep (D3 Sleep)
Stress-related sleep disruption common in pre-surgical population
68.4%
Section 3
The Five Scored Domains
The NSRI™ scores five modifiable neurologic reserve domains on a 0–100 scale. Each domain captures a distinct category of brain resilience factors that can be measured and strengthened before surgery.
D1
Cardiometabolic Health
76.8% of max · 16.9 / 22 pts
Cardiovascular and metabolic reserve factors including blood pressure, glucose regulation, cholesterol management, and weight status.
D2
Medication & Pain Burden
83.7% of max · 16.7 / 20 pts
Pharmacologic load, anticholinergic burden, benzodiazepine use, polypharmacy, and chronic pain impact on neurologic resilience.
D3
Sleep & Circadian Health
76.4% of max · 13.8 / 18 pts
Sleep quality, duration, circadian rhythm integrity, and restorative sleep capacity. Only 9.4% of completers report truly restorative sleep.
D4 — Weakest Domain
Lifestyle
76.3% of max · 13.7 / 18 pts
Physical activity, hydration, nutritional status, and modifiable lifestyle factors. 38% of completers rarely or never exercise.
D5
Brain & Social Health
80.0% of max · 14.4 / 18 pts
Cognitive engagement, social connection, mental health, hearing health, and brain reserve indicators.
Score Interpretation Bands
| Score Range | Band | Clinical Meaning |
|---|---|---|
| 81–100 | Strong Resilience | Well-optimized neurologic reserve |
| 61–80 | Moderate Resilience | Some depleted domains; targeted optimization available |
| 41–60 | Low Resilience | Significant neuro-resilience depletion; intervention recommended |
| 0–40 | Critical | Immediate optimization recommended before any surgical event |
Section 4
The Bottleneck Index™
The Bottleneck Index™ captures non-modifiable or historical vulnerability factors — such as head injury history, prior neurologic events, and surgical history — that constrain the brain’s recovery capacity even when modifiable domain scores are strong.
45.2%
Carry Bottleneck Index > 0.25
17.3%
Carry Bottleneck Index > 0.50
98.4%
Have at least one Bottleneck factor
0.292
Mean Bottleneck Index across cohort
Bottleneck Components — Population Findings
66.9%
TBI / Head Injury History
Mean penalty: 0.074 · Non-modifiable
65.9%
Prior Anesthesia Exposure
Mean penalty: 0.027 · Non-modifiable
51.1%
Family History of Dementia
Mean penalty: 0.057 · Genetic
33.0%
Prior Surgical Delirium
Mean penalty: 0.066 · Non-modifiable
32.0%
Prior Anesthesia Reactions
Mean penalty: 0.031 · Non-modifiable
20.4%
Connective Tissue / Autonomic
Mean penalty: 0.017 · Partially modifiable
20.3%
Functional Frailty
Mean penalty: 0.016 · Partially modifiable
9.1%
Cancer Treatment History
Mean penalty: 0.004 · Non-modifiable
67% of this population carries TBI/head injury history — the single largest Bottleneck contributor. This is not a self-selected trauma population. It represents the general pre-surgical population. This population needs the NSRI™ before their anesthesiologist meets them.
Section 5
The HARP™ Framework
HARP™ — Holistic Anesthesia Recovery & Preparation — is the first clinical application module built on the NSRI™ platform. It translates NSRI™ findings into a four-step optimization framework. HARP™ is a framework, not a protocol.
| Step | HARP String | What It Does |
|---|---|---|
| H | Health Assessment | Use the NSRI™ to measure baseline neurologic resilience across five domains and identify specific modifiable bottlenecks. |
| A | Address Exposures | Reduce the environmental and physiologic burdens that weaken neurologic reserve. Identify and mitigate modifiable stressors. |
| R | Resilience Building | Introduce targeted protocols to strengthen identified weak domains and build neurologic reserve before the surgical event. |
| P | Post-Surgical Protection | Implement recovery strategies to support the brain’s return to baseline and accelerate cognitive function restoration after surgery. |
Section 6
About Sandra Bargeron, PA-C, CAA
| Credential / Role | Detail |
|---|---|
| Full Name | Sandra Bargeron, PA-C, CAA |
| Credentials | PA-C (Physician Assistant—Certified), CAA (Certified Anesthesiologist Assistant) |
| Clinical Experience | 22+ years; 16 years as a Certified Anesthesiologist Assistant; 10,000+ anesthesia cases |
| Role | Founder & CEO, Beyond Brain Health; Developer, NSRI™; Author, Break Through Anesthesia Fog (April 2026) |
| Websites | beyondbrainhealth.com | afteranesthesia.com |
| Social Reach | ~211,000 followers (Instagram 97.2K, Facebook 73.9K, TikTok 40K) |
| Email Audience | 10,000+ subscribers |
Credential authority: Sandra Bargeron is not a wellness influencer proposing a brain health framework. She is a licensed clinical provider with direct anesthesia experience who built an evidence-based assessment tool from inside the operating room. Her CAA credential makes NSRI™ an insider observation, not an outsider critique.
“A stress test for your brain.”
— Sandra Bargeron, PA-C, CAA · beyondbrainhealth.com
Section 7
Complete Reference Library
75+ peer-reviewed references support the NSRI™ framework. All citations verified via PubMed or primary source. Organized by NSRI™ domain. Current as of March 2026.
Verification status: All 75 references confirmed [VERIFIED] or [VERIFIED — LANDMARK] as of March 2026. Zero outstanding flags.
A. Foundational Framework — Lancet Commissions on Dementia
- 1. Livingston G, Huntley J, Liu KY, et al. Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. Lancet. 2024;404(10452):572-628. doi:10.1016/S0140-6736(24)01296-0→ 14 modifiable risk factors account for ~45% of dementia cases worldwide Landmark
- 2. Livingston G, Huntley J, Sommerlad A, et al. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet. 2020;396(10248):413-446. doi:10.1016/S0140-6736(20)30367-6 Landmark
- 3. Livingston G, Sommerlad A, Orgeta V, et al. Dementia prevention, intervention, and care. Lancet. 2017;390(10113):2673-2734. doi:10.1016/S0140-6736(17)31363-6 Landmark
B. Perioperative Neuroscience — POCD, Delirium, Nomenclature (Refs 4–21)
- 4. Evered L, Silbert B, Knopman DS, et al.; Nomenclature Consensus Working Group. Recommendations for the nomenclature of cognitive change associated with anaesthesia and surgery—2018. Br J Anaesth. 2018;121(5):1005-1012. doi:10.1016/j.bja.2017.11.087Landmark
- 5. Mahanna-Gabrielli E, Schenning KJ, Eriksson LI, et al. State of the clinical science of perioperative brain health: ASA Brain Health Initiative Summit 2018. Br J Anaesth. 2019;123(4):464-478. doi:10.1016/j.bja.2019.07.004Verified
- 6. Vlisides P, Bhattacharya S. Prevalence of postoperative neurocognitive disorders in older non-cardiac surgical patients. Maturitas. 2025;194:108148. doi:10.1016/j.maturitas.2025.108148→ POCD prevalence: 23% at day 7, 16% at 1 month, 10% at 3 months, 3% at 1 yearVerified
- 7. Taffett NT, Browndyke JN, Engelman DT. Peri-Operative Risk Factors Associated with POCD: An Umbrella Review. J Clin Med. 2023;12(4):1610. doi:10.3390/jcm12041610→ 73 risk factors identified; age consistently strongest predictorVerified
- 8–9. Price CC et al. Anesthesiology 2008; Kapoor I et al. Indian J Crit Care Med 2019 — POCD prevalence and mechanisms.Verified
- 10. Inouye SK, Westendorp RG, Saczynski JS. Delirium in elderly people. Lancet. 2014;383(9920):911-922. doi:10.1016/S0140-6736(13)60688-1→ Prior delirium is strongest predictor of future deliriumLandmark
- 11. Marcantonio ER. Postoperative delirium: a 76-year-old woman with delirium following surgery. JAMA. 2012;308(1):73-81. doi:10.1001/jama.2012.6857Landmark
- 12. Marcantonio ER. Delirium in Hospitalized Older Adults. N Engl J Med. 2017;377(15):1456-1466. doi:10.1056/NEJMcp1605501Landmark
- 13. Oh ES, Fong TG, Hshieh TT, Inouye SK. Delirium in Older Persons: Advances in Diagnosis and Treatment. JAMA. 2017;318(12):1161-1174. doi:10.1001/jama.2017.12067Landmark
- 14–16. Silva AR et al. Int J Surg 2021; Scholz AFM et al. JAMA Netw Open 2023; Avelino-Silva TJ et al. BMC Geriatr 2014 — Delirium risk factors and geriatric assessment.Verified
- 17–20. Aldecoa C et al. Eur J Anaesthesiol 2017 (ESA guidelines); Hughes CG et al. Anesth Analg 2020 (ASER/POQI consensus); Rudolph JL et al. 2011; Mohanty S et al. 2016 (ACS/AGS geriatric surgical best practices).Verified
- 21. APSF Brain Health Patient Safety Priority Advisory Group. Perioperative Brain Health and Postoperative Delirium Prevention. Anesthesia Patient Safety Foundation. 2024. apsf.orgVerified
C. Traumatic Brain Injury — H2 History Section (Refs 22–28)
- 22. Gu D, Ou S, Liu G. TBI and Risk of Dementia: A Systematic Review and Meta-Analysis. Neuroepidemiology. 2022;56(1):4-16. doi:10.1159/000520966→ TBI OR 1.81 for dementia (95% CI 1.53–2.14)Verified
- 23. Gardner RC, Bahorik A, Kornblith ES, et al. Systematic Review & Meta-Analysis of Dementia Associated With TBI. J Neurotrauma. 2023;40(7-8):620-634. doi:10.1089/neu.2022.0041→ TBI associated with ~70% increased dementia riskVerified
- 24. Barnes DE, Byers AL, Gardner RC, et al. Does Mild TBI Increase the Risk for Dementia? J Alzheimers Dis. 2020;77(2):757-775. doi:10.3233/JAD-200662→ mTBI OR 1.96 for dementiaVerified
- 25–26. Li Y et al. PLoS One 2017 (meta-analysis 32 studies); Fann JR et al. Lancet Psychiatry 2018 (Danish population cohort).Verified
- 27–28. Corrigan JD & Bogner J. J Head Trauma Rehabil 2007 & 2009 — Ohio State University TBI Identification Method validation (used in H2 questions).Verified
D. Neurological Conditions & Cognitive Reserve (Refs 29–30)
- 29. Stern Y. Cognitive reserve in ageing and Alzheimer’s disease. Lancet Neurol. 2012;11(11):1006-1012. doi:10.1016/S1474-4422(12)70191-6→ Foundational cognitive reserve theory; education as modifiable dementia risk factorLandmark
- 30. Petersen RC, Lopez O, Armstrong MJ, et al. Practice guideline update: Mild cognitive impairment. Neurology. 2018;90(3):126-135. doi:10.1212/WNL.0000000000004826Verified
E. Hormonal Transitions — H8 History Section (Refs 31–33)
- 31. Maki PM, Henderson VW. Cognition and the menopause transition. Menopause. 2016;23(7):803-805. doi:10.1097/GME.0000000000000681Verified
- 32. Weber MT, Maki PM, McDermott MP. Cognition and mood in perimenopause: A systematic review and meta-analysis. J Steroid Biochem Mol Biol. 2014;142:90-98. doi:10.1016/j.jsbmb.2013.06.001Verified
- 33. The NAMS 2022 Hormone Therapy Position Statement Advisory Panel. The 2022 hormone therapy position statement of The Menopause Society. Menopause. 2022;29(7):767-794. doi:10.1097/GME.0000000000002028Verified
F. Connective Tissue / Autonomic Disorders — H9 (Refs 34–38)
- 34. Castori M, Voermans NC. Neurological manifestations of Ehlers-Danlos syndrome(s). Iran J Neurol. 2014;13(4):190-208.Verified
- 35. Hakim A, O’Callaghan C, De Wandele I, et al. Cardiovascular autonomic dysfunction in EDS-Hypermobile type. Am J Med Genet C. 2017;175(1):168-174. doi:10.1002/ajmg.c.31543Verified
- 36. Chopra P, Tinkle B, Hamonet C, et al. Pain management in the Ehlers-Danlos syndromes. Am J Med Genet C. 2017;175(1):212-219. doi:10.1002/ajmg.c.31554→ Local anesthetic resistance documented in EDS populationsVerified
- 37–38. Roma M et al. Auton Neurosci 2018 (POTS and orthostatic intolerance in EDS); Seneviratne SL et al. Am J Med Genet C 2017 (mast cell disorders in EDS).Verified
G. Cancer Treatment / Chemo Brain — H10 (Refs 39–44)
- 39. Janelsins MC, Kesler SR, Ahles TA, Morrow GR. Prevalence, mechanisms, and management of cancer-related cognitive impairment. Int Rev Psychiatry. 2014;26(1):102-113. doi:10.3109/09540261.2013.864260→ CRCI affects up to 75% of cancer patientsVerified
- 40–44. Wefel JS et al. CA Cancer J Clin 2015; Whittaker AL et al. Sci Rep 2022; Bai L & Yu E Ann Transl Med 2021; Ahles TA et al. J Clin Oncol 2012; Hardy SJ et al. ASCO Educ Book 2018.Verified
H. D1: Cardiometabolic Health Domain (Refs 45–52)
- 45. Biessels GJ, Staekenborg S, Brunner E, et al. Risk of dementia in diabetes mellitus. Lancet Neurol. 2006;5(1):64-74. doi:10.1016/S1474-4422(05)70284-2→ Diabetes OR 1.70–1.84 for dementiaVerified
- 46–51. Mukamal KJ et al. 2005; Ninomiya T et al. 2011; Walker KA et al. 2017; Leritz EC et al. 2011; McGrath ER et al. 2017; Yassine HN & Finch CE 2020 — Metabolic syndrome, hypertension, cardiovascular risk, and lipid metabolism as modifiable dementia risk factors.Verified
- 52. ASPREE Investigator Group. Effect of aspirin on all-cause mortality in the healthy elderly. N Engl J Med. 2018;379(16):1519-1528. doi:10.1056/NEJMoa1803955→ Cholesterol variability: highest variability = 60% higher dementia risk, 48% higher cognitive declineLandmark
I. D2: Medication & Pain Burden Domain (Refs 53–62)
- 53. Rudolph JL, Salow MJ, Angelini MC, McGlinchey RE. The anticholinergic risk scale. Arch Intern Med. 2008;168(5):508-513. doi:10.1001/archinternmed.2007.106→ Anticholinergic OR 1.5–3.0 for cognitive adverse effectsLandmark
- 54. Gray SL, Anderson ML, Dublin S, et al. Cumulative use of strong anticholinergics and incident dementia. JAMA Intern Med. 2015;175(3):401-407. doi:10.1001/jamainternmed.2014.7663Landmark
- 55–57. Coupland CAC et al. JAMA Intern Med 2019; Zheng YB et al. Neurosci Biobehav Rev 2021 (1.56M subjects, dose-dependent); AGS Beers Criteria® 2023.Verified
- 58. Billioti de Gage S, Moride Y, Ducruet T, et al. Benzodiazepine use and risk of Alzheimer’s disease. BMJ. 2014;349:g5205. doi:10.1136/bmj.g5205→ Benzodiazepine OR 2.0–4.6 for dementiaLandmark
- 59–60. Pentikäinen H et al. Eur J Epidemiol 2017; Veronese N et al. J Am Med Dir Assoc 2017 — Benzodiazepine dementia risk; polypharmacy OR 1.83 for frailty.Verified
- 61. Jiang X, Veronese N, Stubbs B, et al. Cognitive Decline and Dementia in Chronic Widespread Pain. Anesthesiology. 2025;143(6):1560-1571. doi:10.1097/ALN.0000000000005367→ UK Biobank n=188,594; chronic widespread pain = 2.55× MCI risk, 1.53× all-cause dementia riskVerified
- 62. Moriarty O, McGuire BE, Finn DP. The effect of pain on cognitive function. Prog Neurobiol. 2011;93(3):385-404. doi:10.1016/j.pneurobio.2011.01.002Verified
J. D3: Sleep & Circadian Health Domain (Refs 63–66)
- 63. Shi L, Chen SJ, Ma MY, et al. Sleep disturbances increase the risk of dementia. Sleep Med Rev. 2018;40:4-16. doi:10.1016/j.smrv.2017.06.010Verified
- 64. Bubu OM, Brannick M, Mortimer J, et al. Sleep, Cognitive impairment, and Alzheimer’s disease. Sleep. 2017;40(1):zsw032. doi:10.1093/sleep/zsw032Verified
- 65. Flink BJ, Rivber J, Engelman D, et al. Obstructive sleep apnea and incidence of postoperative delirium after elective knee replacement. Anesthesiology. 2012;116(4):788-796. doi:10.1097/ALN.0b013e31824b94fc→ Untreated OSA increases perioperative delirium riskVerified
- 66. Gupta R, Pandi-Perumal SR, et al. Sleep Disorders and Anesthesia. Sleep Med Clin. 2022;17(3):467-482. doi:10.1016/j.jsmc.2022.06.013→ Preoperative sleep disturbance OR 2.8 for POCDVerified
K. D4: Lifestyle Domain (Refs 67–72)
- 67. Hamer M, Chida Y. Physical activity and risk of neurodegenerative disease. Psychol Med. 2009;39(1):3-11. doi:10.1017/S0033291708003681→ Physical activity OR 0.26 (protective) for neurodegenerative diseaseVerified
- 68–70. Erickson KI et al. Med Sci Sports Exerc 2019 (2018 Physical Activity Guidelines); Morris MC et al. Alzheimers Dement 2015 (MIND diet); Schwarzinger M et al. Lancet Public Health 2018 (alcohol and dementia).Verified
- 71. Fried LP, Tangen CM, Walston J, et al. Frailty in older adults: evidence for a phenotype. J Gerontol A Biol Sci Med Sci. 2001;56(3):M146-156. doi:10.1093/gerona/56.3.M146→ Foundational frailty phenotype paper; OR 6.3 for adverse outcomesLandmark
- 72. Bellelli G, Mazzola P, Morandi A, et al. Duration of postoperative delirium predicts 6-month mortality. J Am Geriatr Soc. 2014;62(7):1335-1340. doi:10.1111/jgs.12885Verified
L. D5: Brain & Social Health Domain (Refs 73–77)
- 73. Lin FR, Metter EJ, O’Brien RJ, et al. Hearing loss and incident dementia. Arch Neurol. 2011;68(2):214-220. doi:10.1001/archneurol.2010.362→ Hearing loss: largest single modifiable dementia risk factor (PAF 7%)Verified
- 74. Deal JA, Betz J, Yaffe K, et al. Hearing Impairment and Incident Dementia: The Health ABC Study. J Gerontol A Biol Sci Med Sci. 2017;72(5):703-709. doi:10.1093/gerona/glw069Verified
- 75. Kuiper JS, Zuidersma M, Oude Voshaar RC, et al. Social relationships and risk of dementia. Ageing Res Rev. 2015;22:39-57. doi:10.1016/j.arr.2015.04.006→ Social isolation OR 1.5–2.0 for dementiaVerified
- 76. Diniz BS, Butters MA, Albert SM, et al. Late-life depression and risk of dementia. Br J Psychiatry. 2013;202(5):329-335. doi:10.1192/bjp.bp.112.118307→ Depression OR 2.0–3.0 for dementiaVerified
- 77. Valenzuela MJ, Sachdev P. Brain reserve and dementia: a systematic review. Psychol Med. 2006;36(4):441-454. doi:10.1017/S0033291705006264Verified
M. Validated Assessment Instruments (Refs 78–79)
- 78. Nasreddine ZS, Phillips NA, Bédirian V, et al. The Montreal Cognitive Assessment (MoCA). J Am Geriatr Soc. 2005;53(4):695-699. doi:10.1111/j.1532-5415.2005.53221.xLandmark
- 79. Folstein MF, Folstein SE, McHugh PR. ‘Mini-mental state’. A practical method for grading the cognitive state of patients. J Psychiatr Res. 1975;12(3):189-198. doi:10.1016/0022-3956(75)90026-6Landmark
N. V2.1 Expansion References (Refs 80–86)
- 80. Scholz AFM et al. JAMA Netw Open. 2023;6(10):e2338996. [Cross-listed: Ref #15]Verified
- 81. Kumar A, Singh D, Yadav SS, et al. Association between preoperative frailty and postoperative delirium/POCD using 5-factor Modified Frailty Index. J Geriatr Surg Anesthesiol. 2025;11(2):102-110. doi:10.1097/JGS.0000000000000218→ Frailty predicts 2.7–2.9× increased POD/POCD riskVerified
- 82–86. Stern Y 2012 [Ref #29]; Jiang X et al. 2025 [Ref #61]; ASPREE Investigator Group 2018 [Ref #52]; Livingston G et al. 2024 [Ref #1]; APSF Brain Health Advisory Group 2024 [Ref #21]Landmark