Pathophysiology, Risk Factors, and Systemic Toxicity of Local Anesthetics in Dentistry Regarding Contemporary Management: A Narrative Review

Abstract

Local anesthetic systemic toxicity (LAST) is a rare but potentially life-threatening complication in dental practice. Despite its low incidence, it may lead to serious neurological and cardiovascular consequences. The aim of this narrative review was to provide a comprehensive evaluation of the pathophysiology, clinical manifestations, risk factors, diagnosis, prevention, and contemporary management strategies of LAST from a dental perspective. The current literature indicates that both patient-related and procedure-related variables, including the type and dosage of the local anesthetic agent, injection site, block technique, age, pregnancy status, and underlying systemic diseases, significantly influence the risk of systemic toxicity. In addition to atypical and delayed-onset presentations, cases characterized solely by cardiovascular instability or mild neurological symptoms underscore the need for sustained clinical vigilance during all local anesthetic procedures. Once LAST occurs, management is primarily supportive and symptom oriented. Early recognition, prompt airway stabilization, seizure control, and timely administration of intravenous lipid emulsion therapy constitute the cornerstone of reducing morbidity and mortality. In dental practice, the use of the lowest effective dose of local anesthetics, careful aspiration techniques, and meticulous assessment of high-risk patients are essential preventive strategies.

Keywords

• Local anesthetics
• Local anesthetics systemic toxicity
• LAST
• Lipit emulsion therapy

Diş Hekimliğinde Lokal Anestezik Sistemik Toksisitesi: Patofizyoloji, Risk Faktörleri ve Güncel Yönetim Yaklaşımlarına İlişkin Anlatımsal Bir Derleme

Abstract

Lokal anestezik sistemik toksisitesi (LAST), diş hekimliği pratiğinde nadir görülmesine rağmen ciddi ve yaşamı tehdit eden etkilere yol açabilen önemli bir komplikasyondur. Bu anlatımsal derlemenin amacı, LAST’ın patofizyolojisi, klinik bulguları, risk faktörleri, tanı, önleme ve güncel tedavi yaklaşımlarını diş hekimliği perspektifinden bütüncül biçimde değerlendirmektir. Mevcut literatür; kullanılan lokal anestezik ajanın türü ve dozu, enjeksiyon bölgesi, blok tekniği, yaş, gebelik ve eşlik eden sistemik hastalıklar gibi hasta ve işlemle ilişkili değişkenlerin sistemik toksisite riskini anlamlı düzeyde etkilediğini göstermektedir. Atipik ve gecikmiş başlangıçlı olguların yanı sıra yalnızca kardiyovasküler bozulma veya hafif nörolojik belirtilerle seyreden tabloların varlığı, her lokal anestezi uygulamasında klinik farkındalığın sürdürülmesi gerektiğini ortaya koymaktadır. LAST geliştiğinde tedavi esas olarak semptomatiktir; erken tanı, havayolunun güvence altına alınması, nöbet kontrolü ve uygun dozda intravenöz lipid emülsiyonu uygulanması mortalite ve morbiditenin azaltılmasında temel basamakları oluşturur. Diş hekimliği pratiğinde lokal anestezik kullanımı için etkili en düşük dozun tercih edilmesi, dikkatli aspirasyon tekniklerinin benimsenmesi ve yüksek riskli hastaların titizlikle değerlendirilmesi büyük önem taşımaktadır.

Keywords

• Lokal anestezikler
• Lokal anestezik sistemik toksisitesi
• LAST

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