Abstract
Background
Local anesthetic systemic toxicity (LAST) is a preventable complication associated with regional anesthesia. When multiple local anesthetic (LA) agents are administered during dental procedures, calculating the cumulative fractional toxicity is cognitively demanding and error-prone. Studies have demonstrated that up to 87% of dental practitioners cannot correctly calculate the LA doses. The risk is amplified in pediatric patients, where fatal overdoses have been reported from dosing calculation errors. Despite the clinical importance of accurate dosing, no freely available peer-reviewed tool combines cartridge-based input, cumulative fractional toxicity calculations, and epinephrine dose tracking in dental practice.
Methods
MaxSafe is a free open-source web application. The tool accepts patient weight, age (less than 1 year through 17 years or adult), and status (with independent cardiac and pregnant toggles). It provides five common dental LA formulations with multiple epinephrine concentration options, and uses dental cartridge counts as the input. It calculates the cumulative fractional toxicity in real-time and independently tracks the epinephrine dose against patient-specific limits. In the pediatric mode, the tool applies the American Academy of Pediatric Dentistry (AAPD) Conservative maximum recommended doses and visually restricts age-inappropriate drugs. Additional features include multi-concentration tracking per drug, advisory warnings for hepatic and renal impairments, and a verification summary panel to mitigate automation bias. The accuracy was validated against 23 manually calculated clinical test scenarios, including adult dosing, pediatric dosing, and alternative epinephrine concentration calculations.
Results
The app-calculated values matched the manual calculations exactly across all 23 test scenarios. In pediatric scenarios, the AAPD Conservative maximum recommended doses were substantially more restrictive than the Food and Drug Administration-labeled values; a single cartridge of lidocaine in an 8-kg infant produced 96.6% cumulative LA toxicity, and two cartridges of mepivacaine in an 18-kg child exceeded the safe threshold at 128.8%.
Conclusion
MaxSafe is a validated, free, open-source clinical decision-support tool that automates fractional toxicity calculations and epinephrine dose tracking for multi-agent LA administration in both adult and pediatric dental practices. This tool is available as a progressive web application at https://thesorenc.github.io/maxsafe-local-anesthesia/.
Keywords: Anesthetics, Local; Decision Support Systems, Clinical; Drug Dosage Calculations; Drug Toxicity; Epinephrine; Patient Safety; Pediatric Dentistry
INTRODUCTION
Local anesthetic systemic toxicity (LAST) is a rare but potentially life-threatening complication of regional anesthesia, with an estimated incidence of 0.03% for peripheral nerve blocks [1]. LAST presents initially with central nervous system symptoms, including perioral numbness, tinnitus, and seizures, and may progress to cardiovascular collapse in severe cases [1]. Although lipid emulsion therapy has improved patient outcomes, prevention through accurate dose calculations remains the primary safety strategy.
In dental and oral surgical practices, the risk of cumulative toxicity is amplified in clinical scenarios requiring higher total local anesthetic (LA) volumes, such as bilateral nerve blocks, multi-quadrant surgery, and procedures combining multiple agents for different clinical purposes. When multiple agents are administered, their toxicities are additive, and the safe cumulative dose is governed by the additive dose principle (referred to as the fractional toxicity rule) [2]:
where each fraction represents the ratio of the administered dose to the maximum recommended dose (MRD) of the agent. If the sum exceeds 1.0, the cumulative dose exceeds the theoretical safety threshold.
In addition to cumulative LA toxicity, epinephrine coadministered as a vasoconstrictor introduces a second independent safety constraint. The maximum recommended epinephrine dose for cardiac-compromised patients (0.04 mg) is five-fold lower than that for healthy patients (0.2 mg), and this limit can be reached at routine clinical doses [3,4].
Performing these calculations in real-time while managing dental procedures is cognitively demanding. Survey data indicate that 69% of dental practitioners cannot identify the maximum recommended dose; in a separate measure, 87% cannot correctly calculate the LA dose for a given patient weight [5]. A recent evaluation of generative artificial intelligence chatbots found unsafe dosing recommendations in 67%–90% of the test scenarios, with mean exceedances of 140%–217% above the safe doses [6].
The risk of dosing errors is amplified in pediatric patients, where the safety margin is substantially narrower. Saraghi et al. described a fatal case in which a 5-year-old child received nearly four times the maximum recommended dose of 3% mepivacaine for weight, resulting in seizures, cardiopulmonary arrest, and death [7]. In a recent survey of pediatric dental specialists, 100% reported difficulty calculating the maximum LA dose for children [8].
Several LA dosing tools currently exist; however, each has significant limitations. LoADCalc, the most thoroughly validated published tool, was designed for anesthesiologists performing regional blocks and uses ideal body weight, height, and age as inputs, parameters that are less relevant to dental cartridge-based dosing [9]. It does not include dental-specific formulations or track the epinephrine dose. Online calculators such as howmuchlocal.com and MaxDose offer dental-specific drug libraries, but lack peer-reviewed validation. Paper nomograms provide accurate single-agent calculations but cannot efficiently handle multiagent fractional toxicity in real time [10,11,12]. General medical calculators (e.g., MDCalc) are limited to single-agent dosing without dental-specific features. To our knowledge, as of March 2026, no freely available peer-reviewed clinical decision support tool has combined cartridge-based input, cumulative fractional toxicity calculation, and independent epinephrine dose tracking with patient-specific limits for dental practice.
The purpose of this technical note was to describe and validate MaxSafe, a free, open-source web-based tool designed to address this gap.
METHODS
1. Tool design
MaxSafe is a web-based clinical decision support tool built using React 18 and deployed as a progressive web application with offline support, requiring no installation and functioning on any modern browser, including mobile devices (Fig. 1 and 2). The application accepts patient weight (in kilograms or pounds), patient age (with options ranging from <1 to 17 years or adults), and patient status (with independent toggles for cardiac and pregnant conditions). It provides a library of five common dental LA formulations with pre-populated pharmacokinetic data: lidocaine 2% with epinephrine 1:100,000, articaine 4% with epinephrine 1:100,000, bupivacaine 0.5% with epinephrine 1:200,000, mepivacaine 3% plain, and prilocaine 4% plain. The default epinephrine concentrations for lidocaine and articaine are user-selectable (lidocaine: 1:50,000, 1:80,000, 1:100,000, or 1:200,000; articaine: 1:100,000 or 1:200,000), supporting common dental use, including hemostasis control and cardiac-sensitive dosing.
Fig. 1. MaxSafe web application in adult mode showing patient settings, progress bar gauges with animated percentage readout, sticky summary strip, and drug cards. (A) A 70-kg adult patient receiving 3 carpules of lidocaine 2%, 2 carpules of articaine 4%, and 1 carpule of bupivacaine 0.5%. Cumulative fractional toxicity is 58.6% and epinephrine load is 47.0%, both within the safe range (green). (B) A 70-kg cardiac patient receiving 1 carpule of lidocaine 2%, 1 carpule of articaine 4%, and 1 carpule of mepivacaine 3%. The verification summary banner displays all patient parameters alongside calculated outputs when the epinephrine load exceeds 80%.
Fig. 2. MaxSafe web application in pediatric mode. (A) Patient settings showing the age selector (5 yr selected), AAPD/FDA MRD standard toggle, and weight-for-age validation. (B) Drug card interface for a 20-kg, 6-year-old patient showing bupivacaine greyed out with explanatory overlay (not recommended under 12 years per FDA and AAPD guidelines). Available drug cards display the AAPD Conservative maximum recommended dose and per-concentration carpule counters. The epinephrine limit of 200 mcg (0.2 mg) applies regardless of age. AAPD, American Academy of Pediatric Dentistry; FDA, Food and Drug Administration; MRD, maximum recommended dose.
The tool uses dental cartridge (carpule) counts as the input unit, matches the clinical workflow, and eliminates milligram-to-carpule conversion, which is a known source of dosing errors [5]. As carpules are added, MaxSafe calculates the cumulative fractional toxicity in real time using the aforementioned formula. Simultaneously, it tracks cumulative epinephrine dose against patient-specific limits: 0.2 mg for adult patients, 0.04 mg for cardiac or pregnant patients [3,4].
Two independent color-coded progress bars provide visual feedback with three states: green (≤ 80%, within safe range), amber (80%–100%, approaching limit), and red (> 100%, over limit) (Fig. 3). A persistent summary strip displays cumulative toxicity, epinephrine load, and any active clinical warning (cardiac, pregnancy, hepatic, or renal status). The maximum recommended dose for each agent is calculated as the lesser of the weight-based dose (mg/kg × patient weight) and the absolute maximum dose.
Fig. 3. Additional MaxSafe features. (A) Multi-concentration tracking on a lidocaine drug card, showing independent carpule counters for 1:100,000 and 1:50,000 epinephrine concentrations with an option to add additional concentrations. (B) Clinical Considerations panel (collapsed by default, amber highlight) showing hepatic impairment severity and renal impairment toggles. (C) Verification summary banner displayed when cumulative toxicity exceeds 80%, showing all patient parameters alongside calculated outputs.
No patient data is transmitted or stored. The source code is publicly available under an open-source license at https://github.com/thesorenc/maxsafe-local-anesthesia.
2. Pediatric safety advisory features
MaxSafe includes a dedicated pediatric mode activated by selecting any age from < 1 year through 17 years in the patient age selector. Selecting "Adult" returns to standard adult dosing.
In the pediatric mode, age-restricted drugs are visually greyed out with an explanatory overlay rather than hidden, so the clinician can see which agents exist but are not recommended for the selected age. Restrictions were applied using the stricter Food and Drug Administration (FDA) and American Academy of Pediatric Dentistry (AAPD) guidelines: articaine is restricted for patients under 4 years per FDA labeling, bupivacaine is restricted for patients under 12 years per both FDA and AAPD recommendations, and prilocaine is restricted to patients aged < 1 year owing to methemoglobinemia risk [13,14]. For prilocaine in patients aged 1–5 years, the effective maximum dose is reduced to 2.5 mg/kg with a methemoglobinemia warning, reflecting the published thresholds for symptomatic methemoglobinemia in young children [14]. A selectable dosing standard toggle allows clinicians to choose between the AAPD Conservative maximum recommended doses (default) and FDA-labeled doses. AAPD Conservative values, derived from the AAPD Best Practices guideline for Use of Local Anesthesia for Pediatric Dental Patients (2023 revision), recommend lower maximum doses for lidocaine (4.4 vs. 7.0 mg/kg) and mepivacaine (4.4 vs. 6.6 mg/kg), providing an additional safety margin [13].
In pediatric mode, epinephrine is tracked against the same adult limits (0.2 mg for healthy patients; 0.04 mg for cardiac or pregnant patients), as no validated weight-based pediatric epinephrine limit exists in the published literature. The weight-for-age validation flags entered the weights that fall outside the expected CDC growth chart range for the selected age.
3. Additional clinical safety features
To address the risk of automation bias in clinical decision support tools [15,16], MaxSafe incorporates a verification summary panel. When the cumulative toxicity or epinephrine load exceeds 80%, a non-blocking banner displays all patient parameters alongside the calculated outputs, enabling the clinician to verify that the entered parameters match their patient. This approach reduces verification complexity while maintaining workflow efficiency, which is consistent with the American Medical Informatics Association (AMIA) recommendations for responsible clinical decision support design [17] and precedents from certified dose calculators such as PEDeDose [18].
Advisory toggles for hepatic impairment (none, mild, or moderate-to-severe) and renal impairment display clinical guidance banners recommending minimum effective doses and preferential use of articaine, which is primarily metabolized by plasma carboxyesterase, with only 5%–10% metabolized by hepatic CYP enzymes [19,20]. These toggles provide only advisory information and do not modify dose calculations, as evidence-based dose reduction percentages for dental LA agents in organ impairment do not exist in the published literature.
Each epinephrine-containing drug supports multiple concentration options (1:50,000, 1:80,000, 1:100,000, and 1:200,000 for lidocaine), with each concentration tracked independently using its own carpule counter. This allows clinicians to record lidocaine at 1:100,000 for nerve blocks and 1:50,000 for hemostasis in the same procedure, with the cumulative toxicity and epinephrine dose calculated accurately across all concentrations. The default concentration of 1:100,000 reflects practice in the United States; however, 1:80,000 is the standard lidocaine formulation in Japan [21] and is commercially available in other countries [22]. A pregnancy status toggle applies the same epinephrine limit as in cardiac patients (0.04 mg) and visually restricts prilocaine (greyed out) due to methemoglobinemia risk to the fetus, consistent with the American College of Obstetricians & Gynecologists guidelines on oral health care during pregnancy [23]. Cardiac and pregnancy statuses can be selected independently to accommodate patients under both conditions.
4. Drug data sources
Drug-specific pharmacokinetic parameters (concentration, maximum dose per kilogram, and absolute maximum dose) were derived from FDA-approved prescribing information accessed via DailyMed (National Library of Medicine) for each of the five included formulations [19]. The epinephrine dose limits were derived from peer-reviewed clinical guidelines and systematic reviews [3,4]. All values were cross-referenced against current peer-reviewed pharmacology reviews [24].
5. Validation
Twenty-three clinical test scenarios were designed, including adult single-agent dosing (n = 6), adult multi-agent fractional toxicity (n = 5), adult epinephrine tracking for healthy and cardiac compromised patients (n = 4), pediatric dosing with AAPD Conservative MRDs (n = 6), and alternative epinephrine concentration calculations (n = 2). Adult scenarios included varying patient weights (45–120 kg) to test both the weight-based and absolute maximum dose calculations. Pediatric scenarios included patient weights of 8–25 kg across multiple ages, testing for age-based drug restrictions, AAPD Conservative MRDs, and multi-agent fractional toxicity in children. For each scenario, the expected cumulative fractional toxicity and epinephrine load were calculated manually:
| Di (mg) = Ni × Vi × Ci |
| MRDi (mg) = min (W × mi, Ai) |
where Di is the delivered dose of agent i; Ni is carpule count; Vi is carpule volume (mL); Ci is drug concentration (mg/mL); W is patient weight (kg); mi is the weight-based maximum (mg/kg); Ai is the absolute maximum dose (mg); Ei is the epinephrine concentration (mg/mL); and Elimit is the patient-specific epinephrine limit (0.2 mg for healthy patients; 0.04 mg for cardiac or pregnant patients).
The aApp-generated values were compared withto the manually calculated values. The sScenarios were designed to independently cover all three display states for both gauges independently.
RESULTS
The app-calculated values matched the manual calculations for all the 23 test scenarios (Table 1). All three gauge display states (safe, approaching limit, and over limit) were correctly triggered for both the LA toxicity and epinephrine load gauges.
Table 1. Validation summary: app-calculated vs. manually verified values across 23 clinical test scenarios.
| # | Patient | Drug(s) | Carpules | Tox % | Epi % | LA Status | Epi Status |
|---|---|---|---|---|---|---|---|
| Adult scenarios (FDA MRDs, adult epinephrine limits). | |||||||
| 1 | 70 kg, Healthy | Lido | 1 | 6.9 | 8.5 | Safe | Safe |
| 2 | 80 kg, Healthy | Artic | 4 | 54.4 | 34.0 | Safe | Safe |
| 3 | 55 kg, Healthy | Mepi | 7 | 98.3 | 0.0 | Approaching | Safe |
| 4 | 100 kg, Healthy | Lido | 15 | 102.0 | 127.5 | Over | Over |
| 5 | 45 kg, Healthy | Artic | 4 | 86.3 | 34.0 | Approaching | Safe |
| 6 | 120 kg, Healthy | Prilo | 6 | 108.0 | 0.0 | Over | Safe |
| 7 | 60 kg, Healthy | Lido + Artic | 3 + 2 | 56.7 | 42.5 | Safe | Safe |
| 8 | 90 kg, Healthy | Lido + Artic + Bupi | 3 + 2 + 2 | 67.6 | 51.5 | Safe | Safe |
| 9 | 70 kg, Healthy | Lido + Artic | 5 + 5 | 104.1 | 85.0 | Over | Approaching |
| 10 | 60 kg, Healthy | Lido + Artic + Bupi | 5 + 4 + 3 | 135.2 | 90.0 | Over | Approaching |
| 11 | 80 kg, Healthy | Mepi + Lido | 4 + 3 | 71.4 | 25.5 | Safe | Safe |
| 12 | 90 kg, Healthy | Lido + Artic | 7 + 4 | 102.0 | 93.5 | Over | Approaching |
| 13 | 55 kg, Cardiac | Lido + Artic | 1 + 1 | 26.5 | 85.0 | Safe | Approaching |
| 14 | 70 kg, Cardiac | Lido | 3 | 20.8 | 127.5 | Safe | Over |
| 15 | 60 kg, Cardiac | Mepi + Prilo | 5 + 3 | 124.4 | 0.0 | Over | Safe |
| Pediatric scenarios (AAPD Conservative MRDs, adult epinephrine limits). | |||||||
| P1 | 20 kg, 6 yr, Healthy | Lido | 77.3 | 17.0 | Safe | Safe | |
| P2 | 14 kg, 3 yr, Healthy | Lido | 55.2 | 8.5 | Safe | Safe | |
| P3 | 18 kg, 5 yr, Healthy | Mepi | 128.8 | 0.0 | Over | Safe | |
| P4 | 25 kg, 8 yr, Healthy | Lido + Mepi | 2 | 108.2 | 17.0 | Over | Safe |
| P5 | 15 kg, 2 yr, Healthy | Lido | 51.5 | 8.5 | Safe | Safe | |
| P6 | 8 kg, 9 mo, Healthy | Lido | 1 | 96.6 | 8.5 | Approaching | Safe |
| Epinephrine concentration customization scenarios (adult, 70 kg) | |||||||
| E1 | 70 kg, Healthy | Lido (1:80k) | 3 | 20.8 | 31.9 | Safe | Safe |
| E2 | 70 kg, Cardiac | Lido (1:80k) | 3 | 20.8 | 159.4 | Safe | Over |
The epinephrine ratios are 1:100,000, unless otherwise specified. Pediatric scenarios: Articaine restricted for ages < 4 yr (P2, P5, and P6); bupivacaine restricted for ages < 12 yr (all pediatric); and prilocaine restricted for ages < 1 yr (P6). Status thresholds: Safe, ≤ 80%; Approaching, 80%–100%; Over, > 100%. Lido, Lidocaine 2%; Artic, Articaine 4%; Bupi, Bupivacaine 0.5%; Mepi, Mepivacaine 3% (plain); Prilo, Prilocaine 4% (plain). AAPD, American Academy of Pediatric Dentistry; Epi, epinephrine; FDA, Food and Drug Administration; LA, local anesthetic; MRD, maximum recommended dose; Tox, toxicity.
The three adult scenarios illustrate the core clinical utility of this tool. Scenario 9 demonstrated the fractional toxicity use case: a 70-kg healthy patient receiving 5 carpules of lidocaine 2% (170 mg) and 5 carpules of articaine 4% (340 mg). Neither agent individually exceeded its maximum recommended dose (lidocaine MRD: 490 mg; articaine MRD: 490 mg at this weight), but a cumulative fractional toxicity of 104.1% indicated that the theoretical safe threshold was exceeded. Scenario 14 illustrates the epinephrine tracking feature: a 70-kg cardiac patient receiving only 3 carpules of lidocaine 2% with epinephrine 1:100,000 produces an epinephrine load of 127.5% of the 0.04-mg cardiac threshold. Scenario 15 demonstrated that the toxicity could be exceeded by plain formulations alone.
The pediatric validation scenarios demonstrated a substantially narrower therapeutic window in low-weight patients under conservative AAPD dosing. In Scenario P6, a single cartridge of lidocaine in an 8-kg infant produced 96.6% cumulative LA toxicity, approaching the safe threshold with the minimum clinically useful dose. In Scenario P3, two mepivacaine cartridges in an 18-kg child exceeded the AAPD Conservative maximum at 128.8% toxicity. Scenario P4 confirmed the fractional toxicity rule in pediatric patients: two carpules of lidocaine and one carpule of mepivacaine in a 25-kg child produce a combined toxicity of 108.2%, with neither agent individually exceeding its limit.
DISCUSSION
MaxSafe offers several advantages over existing LA dosing approaches: (1) cartridge-based input eliminates the milligram-to-carpule conversion; (2) dual safety tracking simultaneously monitors both cumulative LA toxicity and epinephrine load; (3) patient-specific epinephrine limits automatically adjust for cardiac and pregnant patients; (4) zero-friction deployment requires no download, account, or cost; and (5) open-source code allows institutional review and customization of drug constants.
The validation results demonstrate a substantially narrower therapeutic window with conservative AAPD dosing. A single cartridge of lidocaine in an 8-kg infant produced 96.6% cumulative LA toxicity under AAPD Conservative MRDs, approaching the safe threshold with the minimum clinically useful dose. Under FDA-labeled MRDs, the same dose produced only 60.7% toxicity. The AAPD Conservative MRD option provides an additional safety margin for pediatric dental practitioners, with lidocaine and mepivacaine maximum doses 33%–37% lower than the FDA-labeled values [13].
Automation bias, the tendency to overaccept automated output without engaging in independent clinical judgment, reportedly causes 6%–11% of clinicians to reverse correct decisions when presented with erroneous clinical decision-support advice [15]. Lyell and Coiera demonstrated that the verification complexity is a key contributor to this effect [16]. MaxSafe's verification summary panel addresses this by displaying all input parameters alongside the calculated dose when the cumulative threshold exceeds 80%, enabling clinicians to verify correctness at a glance. This design is consistent with the AMIA guidelines for responsible clinical decision support [17] and mirrors the approach of PEDeDose, a certified pediatric dosing calculator that requires explicit user confirmation while maintaining workflow efficiency [18].
Customizable epinephrine concentrations can accommodate multiple clinical scenarios beyond the United States default of 1:100,000. Higher concentrations (e.g., 1:50,000 lidocaine) are used to enhance hemostasis during surgical procedures, and lower concentrations (e.g., 1:200,000) reduce epinephrine exposure in cardiac-compromised patients, and practitioners may select alternative concentrations based on clinical preference or regional availability. This variation has direct clinical significance: for a cardiac patient with a 40-mcg epinephrine limit, the safe cartridge count ranges from approximately 1.9 cartridges at 1:80,000 to 4.7 cartridges at 1:200,000, a 2.5-fold difference that a calculator locked to a single concentration could not accurately track.
By automating the fractional toxicity calculation and providing visual alerts, MaxSafe reduces the cognitive burden during procedures in which clinician attention is divided between surgical tasks and dosing calculations. The application displays the fractional toxicity formula and individual drug contributions, serving as a teaching resource for residents and students learning LA pharmacology. Real-time display of cumulative dosing can support intraoperative documentation and quality assurance.
This study has some limitations. The maximum recommended doses vary among FDA labeling, textbook references, and institutional protocols; for example, the FDA-approved MRD for lidocaine with epinephrine is 7 mg/kg, while some dental education programs and the AAPD teach 4.4 mg/kg [13,25]. MaxSafe's adult mode uses FDA-labeled values by default, whereas the pediatric mode defaults to AAPD Conservative values with the option of switching to FDA-labeled values. Users should verify against their institutional guidelines. The fractional toxicity rule itself, although widely taught and clinically accepted, has not been prospectively validated in a clinical trial [25].
Pediatric safety advisory features use the AAPD-recommended maximum doses, which are consensus-based rather than derived from randomized controlled trials. No validated weight-based pediatric epinephrine limits exist in the published literature for dental local anesthesia; the tool uses standard adult epinephrine limits for all ages. Age-based drug restrictions reflect the current FDA labeling and AAPD guidelines, but emerging evidence supports the safe use of articaine in children as young as 3 years [26]. The pediatric mode is intended as a safety advisory and not a standalone validated pediatric dosing calculator.
The tool does not implement dose reduction algorithms for hepatic or renal impairment because evidence-based dose reduction percentages for dental LA agents do not exist in the published literature. Amide LA agents undergo hepatic biotransformation primarily via CYP1A2 and CYP3A4, and clearance is reduced in liver disease. A 2–3-fold dose reduction has been recommended for moderate-to-severe cirrhosis based on intravenous lidocaine pharmacokinetic data [27], but this has not been validated for single-dose dental injections. Articaine is a notable exception, as it is primarily metabolized by plasma carboxyesterase, with only 5%–10% metabolized by hepatic CYP enzymes, potentially conferring a safety advantage in hepatically impaired patients [19,20]. In patients with renal impairment, metabolite accumulation may occur after repeated dosing [28]. The American Society of Regional Anesthesia and Pain Medicine practice advisory identifies hepatic and renal dysfunction as risk factors for LAST, but does not specify dose adjustments [29]. MaxSafe provides advisory warnings for these conditions, directing clinicians to exercise their judgment and use the minimum effective dose.
The tool does not consider the site of injection (which affects the absorption rate), concurrent medications affecting LA metabolism, or patient body composition. The current version includes five LA formulations commonly used in dental practice; agents used in other regional anesthesia settings have not yet been included. No prospective clinical outcome studies have evaluated whether the use of this tool reduces the incidence of LAST or dosing errors in practice. MaxSafe is not FDA-cleared as a medical device; it is provided as an educational and clinical decision support tool and includes a prominent disclaimer to this effect.
Future developments can include additional LA formulations, customizable MRD values to accommodate institutional variations, geriatric dosing considerations, ideal body weight adjustments for obese patients, medication interaction screening, and integration with electronic health record systems for automated documentation. Research evaluating the impact of MaxSafe on dosing accuracy and clinical decision-making in simulated and clinical environments is warranted, with particular attention paid to the pediatric population.
ACKNOWLEDGMENTS
The views expressed in this manuscript are those of the authors and do not necessarily reflect the official policies or positions of the Department of Defense, Uniformed Services University of the Health Sciences, or the United States Government.
Footnotes
- Soren A. Christensen: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Resources, Software, Validation, Visualization, Writing – original draft, Writing – review & editing.
- Evan M. Shipp: Supervision, Writing – review & editing.
CONFLICT OF INTEREST: The authors have no conflicts of interest to declare.
FUNDING: This work received no external funding.
ETHICS STATEMENT: This manuscript describes the development and validation of a software tool. No human subjects were involved, and no IRB review was required.
ARTIFICIAL INTELLIGENCE DECLARATION: The authors declare that no artificial intelligence (AI) or AI-assisted technologies were used in the preparation of this manuscript.
References
- 1.El-Boghdadly K, Pawa A, Chin KJ. Local anesthetic systemic toxicity: current perspectives. Local Reg Anesth. 2018;11:35–44. doi: 10.2147/LRA.S154512. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Budney SM, Holcombe TC. A visual method for the safe administration of multiple local anesthetics. Plast Reconstr Surg Glob Open. 2019;7:e2294. doi: 10.1097/GOX.0000000000002294. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Godzieba A, Smektala T, Jedrzejewski M, Sporniak-Tutak K. Clinical assessment of the safe use local anaesthesia with vasoconstrictor agents in cardiovascular compromised patients: a systematic review. Med Sci Monit. 2014;20:393–398. doi: 10.12659/MSM.889984. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Davis B. What dose of epinephrine contained in local anesthesia can be safely administered to a patient with underlying cardiac disease during a dental procedure? J Can Dent Assoc. 2010;76:a36 [Google Scholar]
- 5.Khalil H. Local anesthetics dosage still a problem for most dentists: a survey of current knowledge and awareness. Saudi J Dent Res. 2014;5:49–53. [Google Scholar]
- 6.Suppan M, Fubini PE, Stefani A, Cottet P, Abbas M, Anderson-Frey R, et al. Performance of 3 conversational generative artificial intelligence models for computing maximum safe doses of local anesthetics: comparative analysis. JMIR AI. 2025;4:e66796. doi: 10.2196/66796. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Saraghi M, Moore PA, Hersh EV. Local anesthetic calculations: avoiding trouble with pediatric patients. Gen Dent. 2015;63:48–52. [PubMed] [Google Scholar]
- 8.Bani-Hani T, Al-Fodeh R, Tabnjh A, Leith R. The use of local anesthesia in pediatric dentistry: a survey of specialists' current practices in children and attitudes in relation to articaine. Int J Dent. 2024;2024:2468502. doi: 10.1155/2024/2468502. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Suppan M, Beckmann TS, Gercekci C, Suppan L, Harbarth S, Iten A. Development and preliminary validation of LoAD Calc, a mobile app for calculating the maximum safe single dose of local anesthetics. Healthcare (Basel) 2021;9:799. doi: 10.3390/healthcare9070799. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Williams DJ, Walker JD. A nomogram for calculating the maximum dose of local anaesthetic. Anaesthesia. 2014;69:847–853. doi: 10.1111/anae.12679. [DOI] [PubMed] [Google Scholar]
- 11.Walker JD, Summers A, Williams DJ. A nomogram to calculate the maximum dose of local anaesthetic in a paediatric dental setting. Br Dent J. 2015;218:469–471. doi: 10.1038/sj.bdj.2015.297. [DOI] [PubMed] [Google Scholar]
- 12.Williams D, Splaver T, Walker J. A nomogram for calculation of maximum recommended dose by volume of local anesthetic in pediatric dentistry. Pediatr Dent. 2017;39:150–154. [PubMed] [Google Scholar]
- 13.American Academy of Pediatric Dentistry. The Reference Manual of Pediatric Dentistry 2025-2026. Chicago: American Academy of Pediatric Dentistry; 2025. Use of local anesthesia for pediatric dental patients; pp. 407–414. [Google Scholar]
- 14.Dontukurthy S, Tobias JD. Update on local anesthetic toxicity, prevention and treatment during regional anesthesia in infants and children. J Pediatr Pharmacol Ther. 2021;26:445–454. doi: 10.5863/1551-6776-26.5.445. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Goddard K, Roudsari A, Wyatt JC. Automation bias: a systematic review of frequency, effect mediators, and mitigators. J Am Med Inform Assoc. 2012;19:121–127. doi: 10.1136/amiajnl-2011-000089. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Lyell D, Coiera E. Automation bias and verification complexity: a systematic review. J Am Med Inform Assoc. 2017;24:423–431. doi: 10.1093/jamia/ocw105. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Labkoff S, Oladimeji B, Kannry J, Schiff GD, Lomotan EA, Wright A, et al. Toward a responsible future: recommendations for AI-enabled clinical decision support. J Am Med Inform Assoc. 2024;31:2730–2739. doi: 10.1093/jamia/ocae209. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Higi L, Käser K, Wälti M, Grotzer M, Vonbach P. Description of a clinical decision support tool with integrated dose calculator for paediatrics. Eur J Pediatr. 2022;181:679–689. doi: 10.1007/s00431-021-04261-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.FDA. FDA-approved prescribing information for Xylocaine Dental, Septocaine, Marcaine Dental, Polocaine/Scandonest, and Citanest Plain Dental. DailyMed [serial on the Internet] 2026. Feb, Available from https://dailymed.nlm.nih.gov.
- 20.Oertel R, Rahn R, Kirch W. Clinical pharmacokinetics of articaine. Clin Pharmacokinet. 1997;33:417–425. doi: 10.2165/00003088-199733060-00002. [DOI] [PubMed] [Google Scholar]
- 21.Inoue T, Yamamoto T. Adrenaline dilution in dental local anesthesia for patients with underlying disease. J Dent Anesth Pain Med. 2024;24:297–299. doi: 10.17245/jdapm.2024.24.4.297. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Abu-Mostafa N, Al-Showaikhat F, Al-Imam A, Al-Zahrani A, Al-Ibrahim M. Hemodynamic changes following injection of local anesthetics with different concentrations of epinephrine during simple tooth extraction. J Clin Exp Dent. 2015;7:e471–e476. doi: 10.4317/jced.52321. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23.Committee on Health Care for Underserved Women, American College of Obstetricians and Gynecologists. Committee opinion no. 569: oral health care during pregnancy and through the lifespan. Obstet Gynecol. 2013;122:417–422. doi: 10.1097/01.AOG.0000433007.16843.10. [DOI] [PubMed] [Google Scholar]
- 24.Taylor A, McLeod G. Basic pharmacology of local anaesthetics. BJA Educ. 2020;20:34–41. doi: 10.1016/j.bjae.2019.10.002. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25.Rosenberg PH, Veering BT, Urmey WF. Maximum recommended doses of local anesthetics: a multifactorial concept. Reg Anesth Pain Med. 2004;29:564–575. doi: 10.1016/j.rapm.2004.08.003. [DOI] [PubMed] [Google Scholar]
- 26.Elheeny AA. Articaine efficacy and safety in young children below the age of four years: an equivalent parallel randomized control trial. Int J Paediatr Dent. 2020;30:547–555. doi: 10.1111/ipd.12640. [DOI] [PubMed] [Google Scholar]
- 27.Klotz U. Antiarrhythmics: elimination and dosage considerations in hepatic impairment. Clin Pharmacokinet. 2007;46:985–996. doi: 10.2165/00003088-200746120-00002. [DOI] [PubMed] [Google Scholar]
- 28.Uppal NN, Jhaveri M, Hong S, Lee J, Sharma A, Leehey DJ. Local anesthetics for the nephrologist. Clin Kidney J. 2022;15:186–193. doi: 10.1093/ckj/sfab121. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 29.Neal JM, Barrington MJ, Fettiplace MR, Gitman M, Memtsoudis SG, Riutort KT, et al. The third American Society of Regional Anesthesia and Pain Medicine practice advisory on local anesthetic systemic toxicity: executive summary 2017. Reg Anesth Pain Med. 2018;43:113–123. doi: 10.1097/AAP.0000000000000720. [DOI] [PubMed] [Google Scholar]



