Electrocardiographic and Hemodynamic Effects of Intravenous Infusion of Bupivacaine, Ropivacaine, Levobupivacaine, and Lidocaine In Anesthetized Ewes:

Efficacy and safety of the serratus anterior plane block (SAP block) for pain management in patients with multiple rib fractures in the emergency department: a retrospective study

PURPOSE

Chest trauma is a severe and frequent cause of admission to the emergency department (ED). The serratus anterior plane (SAP) block seems to be an effective method of pain management; however, data on efficacy and safety of a single SAP block performed in the ED by emergency physicians (EP) are limited. This study aimed to compare SAP block performed by the EP in the ED plus standard therapy to standard therapy alone in terms of pain severity at 0-3-6-12-18 and 24 h, total opioid consumption (milligrams of morphine equivalents, MME), respiratory function (SpO2/FiO2 ratio), and adverse events (i.e. pneumothorax, infections in the site of injection, or Local Anaesthetic Systemic Toxicity syndrome due to SAP block) in the first 24 h.

METHODS

This retrospective, monocentric study included adult patients admitted to the Sub-intensive Care Unit (SICU) of the ED with multiple rib fractures between 01/2022 and 03/2023.

RESULTS

156 patients (65.4% male; median age 62 years; median injury severity score 16; median thoracic trauma severity score 8) were included. 75 (48.2%) underwent SAP block. Patients undergoing SAP block showed significantly less pain 3-6-18 h after a single block, required less MME (0 [0-20] vs. 20 [0-40], p < 0.001), showed higher SpO2/FiO2 ratio, and no adverse events were reported.

CONCLUSION

The SAP block, in combination with standard therapy, appeared to be more effective in providing pain relief than standard therapy alone in patients admitted to the SICU for traumatic rib fractures.

Continuous Intravenous Lidocaine Provides Effective Pain Control in a Palliative Child: A Case Report

Lidocaine infusion is often used as part of a perioperative, multimodal pain management plan. We present its use to treat an 8-year-old child with devastating headaches. His symptoms stemmed from an inoperable supratentorial ependymoma that was causing thalamic bleeding and increased intracranial pressure. Many commonly used pain medications are associated with deleterious side effects such as bleeding and excessive sedation. These effects prevent lucidity for interactions, confound neurologic examination. A lidocaine infusion resulted in significant pain relief without these negative side effects. We discuss lidocaine infusion use and considerations for children suffering from intractable headaches.

SK2 channel deletion reduces susceptibility to bupivacaine-induced cardiotoxicity in mouse

Bupivacaine is frequently used for regional anesthesia and postoperative analgesia. However, an inadvertent intravenous injection can cause severe cardiotoxicity, manifesting as arrhythmia, hypotension, and even cardiac asystole. The mechanism of bupivacaine-mediated cardiotoxicity remains unclear. SK2 knockout mice (SK) and wild-type mice (WT) were divided into four groups, with 12 mice per group. We determined the difference in bupivacaine cardiotoxicity between SK2 knockout and WT mice by measuring the time to the first arrhythmia (T_arrhythmia) and the time to asystole (T_asystole). Secondary indicators of cardiotoxicity were the time from the beginning of bupivacaine infusion to 20% prolongation of the QT interval (T_QT) and the time to 20% widening of the QRS complex (T_QRS). T_arrhythmia and T_asystole were significantly longer in the SK-bupi group than in the WT-bupi group (both P < 0.05). T_QT and T_QRS were longer in the SK-bupi group than in the WT-bupi group (all P < 0.05). The time to 25%, 50%, and 75% reduction in HR in the SK-bupi group was significantly longer than in the WT-bupi group (all P < 0.05). Knocking out the SK2 channel can reduce bupivacaine-induced cardiotoxicity in the mouse.

Bradycardia, Hypotension, and Cardiac Arrest: A Complication of Local Anesthetics

Local anesthetics are routinely used in the field of medicine during many procedures, to alleviate acute pain. Although they are relatively safe, they have the ability to produce undesirable neurotoxic and cardiotoxic symptoms when administered intravascularly. Examples of cardiotoxicity include myocardial depression, cardiac arrhythmias, and cardiovascular collapse. The case below describes the adverse events of severe bradycardia, PR prolongation with subsequent heart block, and sinus arrest following an elective knee replacement in a 73-year-old male who received bupivacaine and ropivacaine.

CaMK II γ down regulation protects dorsal root ganglion neurons from ropivacaine hydrochloride neurotoxicity

T-type calcium channels are intimately involved in the local anesthetics neurotoxicity. Does CaMKIIγ regulate T-type calcium currents in local anesthetics neurotoxicity? This study generated pAd-CaMKIIγ and pAd-shRNA adenovirus vectors to up- and down-regulate CaMKIIγ mRNA expression in dorsal root ganglion neurons (DRG). Normal DRG (Normal group), empty vector DRG (Empty vector group), pAd-CaMKIIγ DRG (pAd-CaMKIIγ group) and pAd-shRNA DRG (pAd-shRNA group) were treated or untreated with 3 mM ropivacaine hydrochloride for 4 h. Cell viability, apoptosis rate, CaMKIIγ, pCaMKIIγ, Cav3.2, and Cav3.3 expression were detected. Ultrastructural changes in DRG were observed under a transmission electron microscope. The results demonstrated that the cell viability of DRG treated with ropivacaine hydrochloride decreased markedly, the apoptosis rate, CaMKIIγ, pCaMKIIγ, Cav3.2, Cav3.3 expression increased significantly. CaMKIIγ up-regulation aggravated ropivacaine hydrochloride-induced cell damage and increased Cav3.2 and Cav3.3 expression. In conclusion, CaMKIIγ regulated Cav3.2 and Cav3.3 expression in DRG, which was involved with ropivacaine hydrochloride-induced cell injury.

Midazolam in rabbits terminates dysrhythmias caused by intracerebroventricular ropivacaine

The current study was designed to investigate the mechanisms by which ropivacaine may act within the central nervous system (CNS) to produce cardiotoxicity. Eighty New Zealand rabbits were divided into four groups randomly. In Group 1, 20 rabbits received intracerebroventricular (icv) saline, and then received icv ropivacaine 30 min later. In Group 2, 20 rabbits received icv ropivacaine. Whenever dysrhythmias continued for more than 5 min, 0.1 ml saline was administered into the left cerebral ventricle. Ten minutes later, 0.1 ml midazolam was given into the left lateral ventricle. In Group 3, 20 rabbits received icv ropivacaine, and once the dysrhythmias developed, the inspired isoflurane concentration was increased from 0.75% to 1.50%. In Group 4, 20 animals received an intravenous (iv) phenylephrine infusion until dysrhythmias occurred. In Group 1, the rabbits did not develop dysrhythmias in response to icv saline, whereas dysrhythmias did develop in these animals after icv ropivacaine. In Group 2, icv saline had no effect on the dysrhythmias; however, icv midazolam terminated cardiac dysrhythmias. In Group 3, an increase in the concentration of the inspired isoflurane had no effect on dysrhythmias. In Group 4, icv midazolam had no effect on dysrhythmias in response to iv phenylephrine. Ropivacaine administered directly into the CNS is capable of producing cardiac dysrhythmias; midazolam terminated dysrhythmias presumably by potentiation of γ-aminobutyric acid (GABA) receptor activity. Our results suggest that ropivacaine produces some of its cardiotoxicity not only by the direct cardiotoxicity of the drug, but also by the CNS effects of ropivacaine.

Comparison of bupivacaine, ropivacaine, and levobupivacaine in an equal dose and concentration for sympathetic block in dogs

BACKGROUND AND OBJECTIVES

The aim of this study was to compare the potency of bupivacaine, ropivacaine, and levobupivacaine in an equal dose and concentration for sympathetic block.

METHODS

We measured mean arterial pressure, heart rate (HR), and right and left brachial artery blood flow (BABF) before and after cervicothoracic sympathetic block in 24 dogs. The experimental protocol was designed as follows: (1) left cervicothoracic sympathetic block with 1.0 mL of 0.25% bupivacaine (n = 8), (2) left cervicothoracic sympathetic block with 1.0 mL of 0.25% ropivacaine (n = 8), and (3) left cervicothoracic sympathetic block with 1.0 mL of 0.25% levobupivacaine (n = 8).

RESULTS

Mean arterial pressure and heart rate did not change significantly throughout the study in either group. Left cervicothoracic sympathetic block with 0.25% bupivacaine increased left BABF significantly from 5 to 100 mins after the block (baseline, 100%; peak at 20 mins after the block, 218% +/- 48%; P < 0.01). Left cervicothoracic sympathetic block with 0.25% ropivacaine increased left BABF significantly from 5 to 100 mins after the block (baseline, 100%; peak at 10 mins after the block, 254 +/- 38%; P < 0.01). Left cervicothoracic sympathetic block with 0.25% levobupivacaine increased left BABF significantly from 5 to 80 mins after the block (baseline, 100%; peak at 20 mins after the block, 183% +/- 38%; P < 0.01).

CONCLUSIONS

Ropivacaine may induce a greater increase in vasodilation than bupivacaine and levobupivacaine at the same dose and concentration for sympathetic block in dogs.

[Evaluation of anesthetic effect of ropivacaine in surgery of chronic periapical lessions]

INTRODUCTION

Ropivacaine is used in orthopedcs, gyneacology, surgery, ophtamology, whereas experience about its usage in dentistry is still limited. The aim of this research was to compare the anesthetic effect between local anesthetics ropivacaine and bupivacaine, in surgical disposals of chronical periapical lessions in maxilla.

MATERIAL AND METHODS

The study included the patients that had indications for surgical removal of chronical periapical lessions at one of the frontal teeth of upper jaw. The total total number of examinees was 60, and they were devided in two groups. Ropivacaine chloride (0.75%) was used as a local anesthetic in one group (Naropin 0.75%; Astra Zeneca), and in the other one bupivacaine chloride (0.5%) (Vexelit 0.5%; Zdravlje). The authors applied 1.8 ml of block anesthesia for the n. infraorbitalis (intra-oral approach) as well as 0.2 ml of the local anesthetic from the palatine side for the final branches of N. nasopalatinus in order to observe the following anesthetic parameters. (I) Beginning of anesthesia was followed by the appearence of upper lip numbness. (II) Pain rating scale according to Sisk was used for the objective measurement of the anesthesia quality. (III) The pain intensity during the intervention was measured by visual analogous scale, on which the patient denoted the intensity of pain he had felt during the intervention. (IV) Duration of anesthetic effect--it is followed by soft tissues numbness.

RESULTS AND DISCUSSION

After the ropivacaine application anesthesia effect started in 1.57 min. and after the usage of bupivacaine in 1.67 min. The mean duration of soft tissue numbness after the application of ropivacaine was 321 minutes. Bupivacaine had a shorter anesthetic effect--296.5 minutes. The quality of anesthesia after the usage of ropivacaine was assessed by the surgeons with average mark--1.76. Interventions in which this anesthetic was used were performed with minimal pain and without additional anesthesia. The quality of anesthesia after the usage of bupivacaine (3.03) was statistically much worse (p < 0.01) in comparison to ropivacaine. In visual analogous scale where patients denoted the intensity of pain during the intervention with ropivacaine the marked average value was 30.1 mm while the average value with usage of bupivacaine was 41.7 mm. The patients from the control group, where bupivacaine was used, had much stronger pain, statistically significant (p < 0.05) in comparison to the group where ropivacaine was used. Our results show that the quality of anesthesia that was attained with 0.5% bupivacaine was much worse than the quality of anesthesia after the application of 0.75% ropivacaine.

CONCLUSION

Ropivacaine has a potential to replace bupivacaine completely in cases when there is the indication for its usage in oral surgery (longlasting intervention, interventions followed by intensive postoperational pain, nerve blockade).

The acute toxicity of local anesthetics

IMPORTANCE OF THE FIELD

Systemic toxicity, usually from overdose or intravascular dose, is feared because it mainly affects the heart and brain, and may be acutely life-threatening.

AREAS COVERED IN THIS REVIEW

Pharmacological studies of local anesthetic toxicity have largely been reviewed primarily relating to the evaluation of ropivacaine and levobupivacaine during the past decade. This review/opinion focuses more on the principles and concepts underlying the main models used, from chemical pharmacological and pharmacokinetic perspectives.

WHAT THE READER WILL GAIN

Research models required to produce pivotal toxicity data are discussed. The potencies for neural blockade and systemic toxicity are associated across virtually all models, with some deviations through molecular stereochemistry. These models show that all local anesthetics can produce direct cardiovascular system toxicity and CNS excitotoxicity that may further affect the cardiovascular system response. Whereas the longer-acting local anesthetics are more likely to cause cardiac death by malignant arrhythmias, the shorter-acting agents are more likely to cause cardiac contraction failure. In most models, equi-anesthetic doses of ropivacaine and levobupivacaine are less likely to produce serious toxicity than bupivacaine.

TAKE HOME MESSAGE

Of the various models, this reviewer favors a whole-body large animal preparation because of the comprehensive data collection possible. The conscious sheep preparation has contributed more than any other, and may be regarded as the de facto 'standard' experimental model for concurrent study of local anesthetic toxicity ± pharmacokinetics, using experimental designs that can reproduce the toxicity seen in clinical accidents.

Safety of amide local anesthetics: new trends

IMPORTANCE OF THE FIELD

Local anesthetics have become one of the most common drugs used in daily practice worldwide. Neurologic and cardiovascular events are the most frequent adverse reactions related to local anesthetics use. Recently, new trends have been developed on this topic.

AREAS COVERED IN THIS REVIEW

We performed an overview of the data available so far on local anesthetics adverse reactions. Relevant literature was identified using PubMed search of articles published up to November 2009, including experimental studies, case reports or clinical studies when available. Search terms included: 'local anaesthetics', 'adverse drug reaction', 'pharmacovigilance' and 'complication'.

WHAT THE READER WILL GAIN

Neurologic, cardiovascular and allergic reactions remain the most frequent adverse drug reactions related to local anesthetics in the literature. Studies based on pharmacovigilance systems have highlighted the frequency of adverse reactions little known until now, such as failure of block. Lipid emulsions are included into algorithm for cardiac resuscitation. Recent studies have demonstrated the myotoxicity and chondrotoxic effects of long-acting local anesthetics.

TAKE HOME MESSAGE

Physicians must keep in mind all these adverse reactions to better prevent their occurrence and give the most appropriate treatment.