Smart NOA: paired synthetic examples and decision flow

Educational work by a pre-medical student — not medical advice. Not a clinical protocol, prescription, or patient handout, and not for patient care. See DISCLAIMER. 27 October 2026 | Additive teaching supplement to MANUSCRIPT.md

These examples explain the existing software and selected literature. They are entirely fictional, independent of clinical encounters and shadowing notes. No drugs were administered. They are not a standardized anesthetic regimen, patient-specific recommendations, proof of safety, or a replacement for clinical assessment. The male and female labels describe fictional adults; they do not create a sex-based dosing rule.

For broader procedure-specific choices, see Anesthesia options, standards and synthetic cases. That companion covers clinical discussion outside the simulation.

1. What the program actually does

The program reads a fictional profile and config.yaml, applies a few exact-string profile rules, returns configured per-kg rate values, and repeatedly updates a dexmedetomidine toy concentration model. It samples synthetic HR and MAP independently of concentrations and changes selected in-memory rates when thresholds are crossed. There is no monitor, pump, IV line, patient connection, or clinical feedback model.

ASA class is stored but does not alter these rules. eGFR only affects the ketorolac example rule; it does not adjust dexmedetomidine, ketamine or lidocaine. Comorbidity and allergy matching is case-insensitive substring matching against short lists, and incomplete. "No configured lockout" is not clearance.

2. Literature context and administration concepts

Clinical publications inform the discussion below; they do not validate config.yaml or the simulator. Different drugs serve different purposes. These are separate source contexts, not instructions to combine all listed agents.

A source-supported clinical assessment would determine whether any agent is appropriate before dose arithmetic. Source ranges are not targets to pursue. We do not add a pump mL/hour setting because no drug preparation or verified concentration is modeled.

3. Paired adult profiles

M1 is a fictional 40-year-old male, 180 cm, 80 kg; F1 is a fictional 40-year-old female, 165 cm, 60 kg, not pregnant in the narrative. Both have illustrative ASA II, eGFR 90, no listed allergies or comorbidities, and no stated hepatic disease. They are learning profiles for a hypothetical elective abdominal procedure; no anesthetic suitability or complete plan is established.

Height, sex, pregnancy and hepatic history are narrative metadata only. Neither is passed to Patient. Changing the sex label alone cannot change the output. The two weights were chosen for arithmetic contrast, not because they are normative male/female weights.

These numbers reproduce config.yaml, not clinical prescriptions. In particular the lidocaine arithmetic uses the code's supplied weight, not a verified ideal-body-weight input. It must not be presented as implementation of [L1]. None of the three amounts establishes that combined administration is appropriate. The program computes only the dexmedetomidine mcg/minute conversion internally; the other mass/hour figures are transparent arithmetic in the example script.

4. Step-by-step software trace

The harness uses the unchanged monitor_and_control method with scripted random readings and sleep disabled. Each call below advances one model second; call-local printed T+0s resets, so the JSON supplies a cumulative step index.

Units in the final column remain mcg/kg/hour for dexmedetomidine and mg/kg/hour for the other two agents. GREEN means no configured alert on that step, not a clinically safe state. A low-HR rule uses HR <48; a separate low-MAP rule uses MAP <60. Both execute at step 2, so low HR cannot mask the low-MAP action.

The hold is incomplete: ketamine stays at 0.2 in the loop, even after the hold latches. The explicit rate-generation method zeros all three when it sees an existing latch. It is not automatically called by the loop. The hold is released only by the explicit, logged two-step acknowledge_hold(by, note) then resume_hold(by) (a simulated clinician action), and the release restores no rate; there is no automatic unlatch or restart policy. This is a limitation to teach, not a comprehensive infusion shutdown or rescue protocol.

The model update occurs before each observation's rule action. Step 2 therefore uses the previous nonzero dexmedetomidine rate for that step before zeroing it. An in-memory zero does not remove drug already present or cause instant recovery. At step 3, toy Cp falls slightly while Ce continues rising because it is still below Cp.

For both M1 and F1, toy Cp after steps 1–3 is approximately 0.000173611, 0.000347106 and 0.000346875 ng/mL. Ce is approximately 2.89352e-7, 8.67380e-7 and 1.44406e-6 ng/mL. These are unvalidated numerical states, not therapeutic targets or measured concentrations. Equal weight-normalized inputs and a volume proportional to weight cause weight to cancel mathematically; the matched concentrations do not demonstrate equivalent responses in male and female patients.

5. Older, higher-risk variants

M2 and F2 retain the respective 80/60 kg weights and narrative sex/height, but are aged 78 with eGFR 24 and the exact comorbidity string "Heart Block". Illustrative ASA III is supplied for these fictional variants; it is stored but does not alter the rules. This is not an assessment of a real patient.

For both, the configured cardiac-string rule sets dexmedetomidine to zero from initialization, and the eGFR rule locks the ketorolac adjunct message. Ketamine and lidocaine still start at 0.2 and 1.5 per kg/hour. Those unchanged values expose missing risk adaptation; they are not proposed treatment for these profiles. Dexmedetomidine toy concentrations stay zero, yet the scripted low-HR/low-MAP event still triggers RED. This demonstrates threshold logic independent of a concentration estimate.

Age alone above 65 would select the configured 0.25 dexmedetomidine value if the cardiac lockout were absent. That exact 50% age adjustment is a programming choice, not a guideline-derived geriatric rule. At age exactly 65, eGFR exactly 30, HR exactly 48 and MAP exactly 60, none of these respective strict-threshold branches activates. The harness records this boundary to prevent false assumptions about what the code checks.

6. Decision flows

Existing software flow

flowchart TD
 A[Fictional profile and YAML] --> B[Validate implemented input domains]
 B --> C[Apply selected case-insensitive substring and threshold lockouts]
 C --> D[Return configured example rates]
 D --> E[Sample scripted or random HR and MAP]
 E --> P[Re-zero locked and held values; end an expired suspension]
 P --> S{Reading unusable: missing, non-numeric, outside the plausibility limits or a sudden drop?}
 S -->|Yes| SF[Set all three values to zero; latch hold; RED]
 S -->|No| R{Any rate negative, non-finite or above its ceiling?}
 R -->|Yes| RF[Set that value to zero; latch hold; RED]
 R -->|No| F[Update dexmedetomidine toy Cp and Ce with the rate set before the HR and MAP rules of this step]
 RF --> F
 F --> G{HR below 48?}
 G -->|Yes and suspended| GS[Log suppressed breach; no latch]
 G -->|Yes and not suspended| H[Set dex value to zero and latch hold; RED]
 G -->|No| I{MAP below 60?}
 GS --> I
 H --> I
 I -->|Yes and suspended| IS[Log suppressed breach; no latch]
 I -->|Yes and not suspended| J[Set dex and lidocaine to zero; RED]
 I -->|No| K{Hold already latched?}
 IS --> K
 K -->|Yes, no new HR or rate trip| L[HOLD; no automatic restart]
 K -->|Yes, new HR or rate trip| M[Keep RED]
 K -->|No and no rate trip| N[GREEN means no configured alert]
 SF --> O[Next loop; ketamine is not part of the HR and MAP rules]
 J --> O
 L --> O
 M --> O
 N --> O
 O --> E

flowchart TD
 A[Fictional profile and YAML] --> B[Validate implemented input domains]
 B --> C[Apply selected case-insensitive substring and threshold lockouts]
 C --> D[Return configured example rates]
 D --> E[Sample scripted or random HR and MAP]
 E --> P[Re-zero locked and held values; end an expired suspension]
 P --> S{Reading unusable: missing, non-numeric, outside the plausibility limits or a sudden drop?}
 S -->|Yes| SF[Set all three values to zero; latch hold; RED]
 S -->|No| R{Any rate negative, non-finite or above its ceiling?}
 R -->|Yes| RF[Set that value to zero; latch hold; RED]
 R -->|No| F[Update dexmedetomidine toy Cp and Ce with the rate set before the HR and MAP rules of this step]
 RF --> F
 F --> G{HR below 48?}
 G -->|Yes and suspended| GS[Log suppressed breach; no latch]
 G -->|Yes and not suspended| H[Set dex value to zero and latch hold; RED]
 G -->|No| I{MAP below 60?}
 GS --> I
 H --> I
 I -->|Yes and suspended| IS[Log suppressed breach; no latch]
 I -->|Yes and not suspended| J[Set dex and lidocaine to zero; RED]
 I -->|No| K{Hold already latched?}
 IS --> K
 K -->|Yes, no new HR or rate trip| L[HOLD; no automatic restart]
 K -->|Yes, new HR or rate trip| M[Keep RED]
 K -->|No and no rate trip| N[GREEN means no configured alert]
 SF --> O[Next loop; ketamine is not part of the HR and MAP rules]
 J --> O
 L --> O
 M --> O
 N --> O
 O --> E

Text alternative: each loop re-zeroes locked and held values and ends an expired suspension; an unusable reading zeroes all three values, latches the hold and sets RED; otherwise a rate fault zeroes that agent, the dexmedetomidine toy model updates, and HR below 48 (dexmedetomidine) and MAP below 60 (dexmedetomidine and lidocaine) each latch the hold and set RED unless an explicit suspension is active, in which case the breach is only logged. A latched hold shows HOLD and never restarts on its own; release is the explicit two-step action described above. The full per-second decision tree, generated from config.yaml values, is in SAFETY_DESIGN.md.

Guideline-informed educational discussion, outside this software

Identify procedure and goals → review applicable source population and current local policy → assess contraindications, organ function, interactions, weight metric and monitoring → clinician selects or rejects an intervention → verify units and administration arrangements → observe intended effect and adverse effects → clinician reassesses.

This conceptual sequence is not an executable dosing algorithm. Patient deterioration requires clinical assessment and an established response process; the simulator supplies neither diagnosis nor rescue decisions.

7. What advantages and safeguards can honestly be described?

Clinical benefit remains untested. The POFA trial [P1] did not establish a blanket safety advantage for its dexmedetomidine-based opioid-free strategy and stopped early after severe bradycardia. It did not evaluate Smart NOA or these toy thresholds.

8. Reproduce and inspect

From the repository root, after installing requirements:

python -m unittest discover -v
python example_walkthrough.py > EXAMPLE_RESULTS.json

The harness scripts only input readings and time.sleep using unittest.mock; it calls the existing controller logic. Assertions check event order, the incomplete ketamine hold, the regeneration behavior, unsupported drugs, exact boundaries and equal toy concentrations for matched per-kg inputs. See EXAMPLE_RESULTS.json and example_walkthrough.py. This is software verification, not clinical testing. No production control logic was changed by this supplement.

9. Peer-reviewed DOI sources and claim mapping

• [D1] Weerink MAS et al. Clinical Pharmacokinetics and Pharmacodynamics of Dexmedetomidine. Clinical Pharmacokinetics. 2017;56:893–913. DOI 10.1007/s40262-017-0507-7. Review; section 3 supports the distinct maintenance-dose contexts. Does not validate this model or its constants.
• [K1] Schwenk ES et al. Consensus Guidelines on the Use of Intravenous Ketamine Infusions for Acute Pain Management. Regional Anesthesia and Pain Medicine. 2018;43:456–466. DOI 10.1097/AAP.0000000000000806. Consensus guideline; question 2 supports the cited subanesthetic infusion context, not a complete anesthesia plan.
• [L1] Foo I et al. The use of intravenous lidocaine for postoperative pain and recovery: international consensus statement on efficacy and safety. Anaesthesia. 2021;76:238–250. DOI 10.1111/anae.15270. Consensus recommendations support the weight metric, delivery/monitoring concepts, limits and local-anesthetic overlap discussion.
• [P1] Beloeil H et al. Balanced Opioid-free Anesthesia with Dexmedetomidine versus Balanced Anesthesia with Remifentanil for Major or Intermediate Noncardiac Surgery. Anesthesiology. 2021;134:541–551. DOI 10.1097/ALN.0000000000003725. Randomized trial; supports the caution about assuming clinical benefit, not simulator performance.

Sources checked 27 October 2026 using publisher/PubMed/PMC records and available source text. Source types are identified because a consensus recommendation, pharmacology review and randomized trial answer different questions. Software-behavior claims are evidenced by the code and traces rather than assigned a clinical DOI. This is selected-source teaching material, not a systematic evidence review.