Session 1 Module 8 Local Anesthetics: Painless Injections – Comprehensive Practical Notes

Introduction and Context

• Dr. James Sanderson (clinical advisor, BioHorizons) and Bobby (Babi) Moody host a webinar on local anesthetics focused on painless, effective injections and practical pearls for daily practice.
• Goals: teach how to give a shot that doesn’t hurt, how to achieve profound anesthesia, and how to apply strategies tomorrow in practice.
• Various features of BioHorizons discussed: one-stop shop for surgical needs (biologics, membranes, bone grafting materials), implants, prosthetics (cement, screw-retained, removable or fixed), zirconia or titanium-based abutments, crowns, surgical guides, and partnerships (e.g., Austell for implant stability).
• Emphasis on science, innovation, and service; company identity described as a micro-engineering organization focused on science, delivery, and ongoing innovation (e.g., Laser Lock, three-in-one abutments).
• Audience engagement: attendees were muted; questions welcome via chat window; live Q&A integrated into the session.

Key Concepts and Principles

• Objective: Beginner to advanced comfort and confidence in giving local anesthetics without causing pain; include techniques to minimize tissue trauma and patient anxiety.
• Core teaching themes:
  • Use smallest diameter, short needles to reduce tissue trauma and patient discomfort.
  • Distract the patient during injection (e.g., suction audible near the patient, slow injections).
  • Do injections slowly to avoid expanding tissue and increasing pain.
  • Placement matters: stay near bone to avoid vascular structures (e.g., pterygoid plexus) and to optimize success.
  • Blanching and papilla involvement: blanch tissue in the target area before deeper palatal injections to reduce pain.
  • Use dual-shot strategies (two injections, often two syringes/needles) to maximize effectiveness while keeping tissue trauma low.
  • Plan case dosing carefully; monitor total carpules to avoid toxicity; use weight-based considerations for maximum safe dosing.
  • Have a robust plan for managing local anesthetic toxicity including airway management, emergency response (911), and medications (benzodiazepines for seizures, ACLS readiness, intra-lipid therapy).
  • Consider patient anxiety management and sedation options when appropriate (oral conscious sedation, nitrous oxide with careful titration), and acknowledge limitations and patient experience.
  • Post-procedure analgesia and anti-inflammatory strategies (e.g., Marcaine/bupivacaine infiltration) can reduce postoperative pain and swelling.

Local Anesthetic Agents and Dosing (Practical Highlights)

• Common agents discussed:
  • Lidocaine (workhorse in practice; often with epinephrine)
  • Septocaine (articaine) for broad maxillary numbness; effective in multiple sites with fewer cartridges
  • Marcaine (bupivacaine) for longer-lasting anesthesia and anti-inflammatory effects post-procedure
  • Carbocaine (mepivacaine) mentioned as an option for patients sensitive to epinephrine or certain cases
• Key dosing concepts and examples shared (weight-based rough guide; use these as referenced in the talk):
  • Maxillary anesthesia often uses septocaine; plan three carpules to numb the whole maxilla (patient and operator side approach) and then infiltrate papilla separately if needed.
  • For weight-based planning (examples given):
  • $80\ ext{lbs} \Rightarrow 6.5\ \text{carpules}$
  • $140\ ext{lbs} \Rightarrow 11.5\ \text{carpules}$
  • $200\ ext{lbs} \Rightarrow 13.5\ \text{carpules}$
  • In the mandible, two initial injections are often used to start; if the patient remains numb inconsistently, repeat with a fresh needle to avoid dulling and increased tissue trauma.
  • Two needles and two syringes are recommended for mandibular blocks to avoid dulling a single needle and increasing patient discomfort on re-entry.
• Specific dosing and workflow remarks:
  • Lidocaine dosing: ensure awareness of maximum safe dose; plan to count and document each carpule used; improper counting can lead to overdose risks.
  • Consider using Marcaine post-operatively for anti-inflammatory and analgesic support; anecdotal success with reduced postoperative pain and swelling.
  • Septocaine can be used to numb the entire maxilla with three carpules, followed by papilla infiltration and palate infiltration as needed.

Injection Techniques and Anatomical Guidelines

• Maxillary injections:
  • Posterior maxilla: keep the needle as close to the bone as possible to avoid the pterygoid plexus of veins; avoid deep, poorly directed injections that risk intravascular entry.
  • For teeth like #3 and #14: require two injections (distal and mesial) to anesthetize two nerves.
  • Infraorbital foramen block for maxillary canines through molars and soft tissue to midline; it helps achieve broader soft-tissue numbness.
  • Maxillary anterior: generally easier to numb with infiltration; often 100% success for soft tissue/teeth numbness when using targeted infraorbital approaches.
  • Palatal anesthesia: blanch tissue via penetration in the papilla region first; then proceed to palate with careful needle angling to minimize pain; consider using lidocaine infiltrations at the papillae to assist blanching before palatal access.
• Palatal technique nuances:
  • After infraorbital foramen and papilla blanching, the needle is threaded to the palate with careful bending and positioning to maintain access and patient comfort.
  • The technique emphasizes not rushing to the palate until papilla blanching has occurred to minimize pain and tissue trauma.
• Mandibular injections:
  • Classic teaching is to place the block high; the speaker personally prefers a targeted approach: locate a notch near the mandible (by the patient’s thumb) to guide the entry; if the bone is hit, redirect slightly and use a short needle to stay in intended anatomy.
  • For mandibular blocks, start with two injections and reassess after ~5 minutes; if numbness is insufficient, repeat with a fresh needle.
  • Mental foramen approach: bend the needle to point straight downward toward the foramen; avoid directing the syringe directly at the patient’s eyes for safety and comfort.
  • Long buccal nerve considerations: often used after confirming mandibular numbness; primarily for soft tissue anesthesia and lip numbness up to the midline; not always first-line if mandibular nerve is not yet fully numbed.
• Distraction and cooperation techniques during injection:
  • Use suction near the patient’s ear to create auditory distraction and reduce perceived pain; couple with slow administration.
  • Encourage breathing through the nose and relaxing the patient; communicate progress and comfort for reassurance.
  • Explicitly acknowledge patient anxiety, which helps the patient stay calm and comfortable.

The Two-Syringes, Two-Needles Concept (Two Shots) and Practical Workflow

• Two needles, two syringes approach:
  • After one initial injection, use a fresh needle for the second injection to ensure sharpness and minimize tissue trauma.
  • This approach reduces patient pain associated with dull needles and helps ensure consistent anesthesia.
  • The assistant’s role is crucial: prepping two syringes, two carpules, and two needles; helps ensure no dulling or reuse of a dull needle.
• Rationale shared by clinicians:
  • A dull needle will create greater tissue disruption and pain when the second injection is performed.
  • Fresh needles and clean carpules reduce discomfort and increase the likelihood of patient cooperation and numbness in hard-to-numb areas.

Mouthpiece Management, Sedation, and Patient Experience

• Anxiety management strategies:
  • Oral conscious sedation (e.g., liquids) and dedicated calming spaces can help reduce stress; nitrous oxide is effective but requires careful titration and patient selection.
  • Some experiences with nitrous were negative due to poor setup or patient expectations; the presenter emphasizes preparation and communication to improve outcomes.
  • Create a calm environment (e.g., dedicated La-Z-Boy lounge area) to reduce overall operatory stress.
• Sedation pitfalls and cautions:
  • Over- or under-dosing of nitrous can cause discomfort, dizziness, or nausea; patient education about the experience is crucial.
  • If nitrous alone is insufficient or unsuitable, consider staged sedation or returning another day with a better plan.
• Topical anesthetics:
  • Topicals were present in the office but not universally trusted by clinicians in the room; effectiveness and patient acceptance varied.
  • When used, topical gels require a minimum waiting time of about five minutes to achieve effect; improper timing wastes resources and effort.

Toxicity, Emergency Preparedness, and Management of Complications

• Recognizing toxicity signs:
  • Early signs include disorientation, shaking, slurred speech, decreased muscle tone, and sudden changes in blood pressure.
  • If toxicity occurs, slow down and consider airway management, seek help, and be ready to perform emergency interventions.
• Immediate actions in-office:
  • Stop what you’re doing, call for help (911 in the US), and have a notepad or recording team document events, timing, and interventions.
  • Prepare for airway management, possible seizures, and cardiac arrhythmias; have benzodiazepines for seizures and ACLS training available.
  • Consider intralipid 20% lipid emulsion therapy as a rescue option in severe local anesthetic toxicity scenarios.
• Post-event protocol and learning:
  • Avoid pushing the envelope; if trouble escalates, step back and defer or reschedule rather than risk patient harm.
  • Practitioners should pursue formal training (ACLS, airway management, sedation protocols) to improve readiness for rare but serious events.

Real-World Scenarios and Personal Anecdotes

• Personal story: a dental student’s painful first experience with shots, and a turning point when the father shared new techniques (e.g., smaller needles, short needles, tissue over needle technique, suction for distraction, slow injections).
• Assistant perspective: slow injections are magical for patient comfort; managing the patient’s perception of time and pain is essential.
• User anecdotes about sedation choices and experiences:
  • Oral conscious sedation can be effective when properly planned.
  • Nitrous oxide experiences varied; importance of appropriate setup and patient education.
  • Some patients have had negative experiences with nitrous or sedation due to previous experiences or mismanaged dosing.
• Redhead and smoker considerations (anecdotal): redheads may bruise more and require more careful numbness; smokers may present different anesthetic challenges depending on context and regional differences.
• Practical takeaway: a well-prepared team, careful dosing, and a calm patient experience can dramatically improve anesthesia success and patient satisfaction.

Practical Takeaways and Pearls (Summary Best Practices)

• Before injections:
  • Prepare two syringes, two carpules, and two needles for mandibular injections to ensure sharpness and reduce pain from dull needles.
  • Plan injections so the patient understands the process and what to expect; communicate calmly and clearly.
  • Ensure proper pretreatment for anxious patients (sedation options, environmental adjustments).
• During injections:
  • Use the smallest available needle and short needles; avoid puncturing tissue; gently wiggle and insert with the tissue pulled away.
  • Maintain a slow injection pace; use distraction (suction, audio cues) to reduce patient stress.
  • For maxillary posterior injections, stay near bone to avoid pterygoid plexus; for infraorbital blocks, rely on foramen targeting for broader numbness.
  • For palatal injections, blanch the papilla first and infiltrate through papilla before deeper palatal access; avoid rushing to the palate before blanching.
  • In mandibular anesthesia, use the notch-by-thumb entry approach to locate bone and avoid hitting sensitive structures; confirm numbness after initial injections before proceeding.
• After injections:
  • Consider Marcaine infiltration at the end of surgery to reduce post-op pain and swelling.
  • Track and manage total carpules administered; avoid exceeding maximum safe doses; document every cartridge used.
  • Reassess numbness before starting procedures; if incomplete, consider additional infiltration with care.
• In case of complications:
  • Recognize toxicity early and stop injections; call for help and follow emergency protocols; use intralipid therapy if indicated.
  • Maintain airway safety and consider calling emergency services if necessary; ensure documentation and post-event review.
• Ethical and practical implications:
  • Acknowledge the opioid crisis and emphasize safer analgesia strategies and non-opioid pain control when appropriate.
  • Focus on patient comfort, informed consent, and transparent communication about what to expect during anesthesia.

Final Reflections and Resources

• The speakers emphasize ongoing innovation and the value of practical, experience-based pearls that can be applied immediately in practice.
• They encourage continued learning, safe sedation practices, and preparedness for emergencies.
• Webinar recaps and access will be provided post-session; contact information for Dr. Sanderson and BioHorizons is available for follow-up questions.