Toxicity of Local Anesthetics:

Local Hematoma Block as Postoperative Analgesia in Pediatric Supracondylar Humerus Fractures

Purpose

Supracondylar humerus fracture (SHF) is the most common type of fracture in children. The aim of this study was to evaluate the efficacy of local hematoma block with 0.25% bupivacaine as postoperative pain control in patients with pediatric SHF who underwent closed reduction pin fixation.

Methods

We performed an institutional review board–approved, prospective cohort study of 65 patients with SHF treated with closed reduction percutaneous pin fixation. For 6 months, all patients were randomly divided into 2 groups. The treatment group (35 patients) received an intraoperative local hematoma block using 0.25% bupivacaine whereas the control group (30 patients) did not receive a local hematoma block as postoperative pain management adjuvant. After surgery, all patients were prescribed opioid pain medication. To evaluate the efficacy of the hematoma block, postoperative morphine equivalent consumption and the Faces Pain Scale–Revised (FPS-R) survey were blindly recorded during postoperative day 1. Demographic data, surgical details, clinical neurovascular examination during the hospital stay, and complications were also evaluated.

Results

Comparison of the control group with the treatment group showed similar morphine equivalent consumption and Face Pain Scale–Revised Survey results. No hematoma block-associated complications were reported.

Conclusions

The result of this study do not favor the use of local hematoma block to improve pain control and decrease the need for opioid use on postoperative day 1 in pediatric SHF after patients undergo closed reduction percutaneous pin fixation. These results can lay the foundation for future studies while suggesting new, novel opioid-free pain control strategies in patients with SHF.

Type of study/level of evidence

Therapeutic II.

Electrophysiological responses in Amazonian fish species Bryconops caudomaculatus (Osteichthyes: Characiformes) as biomarkers of xenobiotic toxicity

Sublethal exposures to environmental pollutants may cause changes in physiological parameters. Thus, knowledge of basal physiological rates of the species and the development of methods to quantify these rates are extremely important. Considering the scarcity of cardiac and muscle physiological studies in native Amazonian fish species and that no evaluation of electrophysiological responses by exposure to a stressor has been reported in Bryconops caudomaculatus, the aim of this study was to develop techniques of electromyographic and electrocardiographic recordings of normal responses, during toxicity induction and short-term recovery. A total of 9 animals were used, divided into two groups: control group (n = 4) and treated group (n = 5), with records lasting 5 min. The results showed that the basal electromyographic records indicate that the studied species has a very intense swimming activity, whereas the basal cardiac parameters clearly showed the patterns in P wave tracing, QRS complex, T wave and Q-T and R-R intervals. During exposure to the stressor, muscle activity ceased presenting intense decrease and myorelaxant effect expected. Electrocardiographic responses confirmed cardiotoxicity with intense bradycardia, ventricular bigeminism, prolongation of QRS complex duration and cardiac arrhythmias, indicating cardiac dysfunction. It was concluded that the electrophysiological responses are excellent biomarkers and showed the susceptibility of the species to the tested substance. In addition, the electrocardiogram and the electromyogram are excellent techniques to reflect the degree of environmental stress when organisms are exposed to toxic substances in the environment.

Efficacy and safety of bupivacaine versus lidocaine in local anesthesia of the nasopharynx: A meta-analysis

PURPOSE

To assess the efficacy and safety of bupivacaine compared with lidocaine in local anesthesia of nasopharynx through meta-analysis.

METHODS

A number of medical literature data bases were searched electronically. Relevant journals and references of included studies were manually searched. Two reviewers independently performed data extraction and quality assessment.

RESULTS

Four studies were included. Visual analog scale (VAS) scores, acceptable discomfort, and bleeding scores were analyzed for bupivacaine versus lidocaine. When considering the VAS scores, bupivacaine as a local anesthetic agent was better than lidocaine in controlling the pain of postoperative patients (p < 0.00001). From VAS scores of patients for transnasal fiberoptic nasopharyngolaryngoscopic examination that was performed to evaluate upper airway structures, lidocaine was found to be better at pain management in patients who underwent transnasal endoscopic examination (p < 0.00001). However, when analyzing the acceptable discomfort of patients who underwent upper gastrointestinal endoscopy, which serves as a valuable tool to evaluate upper gastrointestinal structures, the patients in the bupivacaine group demonstrated a higher acceptable discomfort than the patients in the lidocaine group (p = 0.008). With regard to the bleeding scores of the patients with nasal surgery, lidocaine was better at bleeding in postoperative patients compared with bupivacaine (p = 0.0007). These results indicated that bupivacaine showed better pain control of postoperative patients and acceptable discomfort in patients with upper gastrointestinal endoscopy. Lidocaine had a significantly increased ability the pain of patients with transnasal fiberoptic nasopharyngolaryngoscopic examination and bleeding in postoperative patients. No systemic adverse events were reported.

CONCLUSION

Bupivacaine was found to have better promotion to pain control than did lidocaine for the patients after nasal surgery. Lidocaine had a significantly increased inhibition of bleeding in these postoperative patients; however, the efficacy between bupivacaine and lidocaine was unclear for the patients who had transnasal endoscopic examinations.

Lipídeos nas intoxicações por anestésicos locais

INTRODUÇÃO: Com o advento dos anestésicos locais de longa duração, a anestesia locorregional ganhou grande impulso sendo cada vez mais utilizada. Novas técnicas de bloqueios foram descritas e a técnica é frequentemente associada à anestesia geral com o objetivo de proporcionar analgesia pós-operatória. A contra-partida é a necessidade da utilização de grandes doses com risco de acidentes por injeção intravascular inadvertida; trata-se de complicação grave sem tratamento específico até há alguns anos. Em 1998 foi proposta a utilização de emulsões lipídicas em animais e a partir de 2006 vários trabalhos demonstraram o interesse dessas soluções nos casos de intoxicações por anestésicos locais com diminuição da morbi-mortalidade. O objetivo desta revisão foi fazer um levantamento da metodologia, revisando os mecanismos, interesses, limites e as condutas preconizadas atualmente. MÉTODO: Foram revistas algumas referências históricas sobre anestésicos locais, artigos publicados nos últimos 30 anos em revistas indexadas no Medline e em dois livros-texto. Foram selecionados os artigos que tratavam da intoxicação por anestésicos locais, da terapia com emulsões lipídicas, os de revisão sobre o assunto e as condutas adotadas em diversos serviços e países, sendo realizada uma síntese. CONCLUSÕES: A eficiência e interesse da terapia com emulsões lipídicas nas intoxicações por anestésicos locais não é mais a demonstrar; várias sociedades da especialidade já publicaram suas diretrizes e aconselham que se disponha desses produtos nos locais onde se pratica a anestesia locorregional.