This review summarizes current knowledge concerning incidence, risk factors, and mechanisms of perioperative nerve injury, with focus on local anesthetic-induced neurotoxicity. Perioperative nerve injury is a complex phenomenon and can be caused by a number of clinical factors. Anesthetic risk factors for perioperative nerve injury include regional block technique, patient risk factors, and local anesthetic-induced neurotoxicity. Surgery can lead to nerve damage by use of tourniquets or by direct mechanical stress on nerves, such as traction, transection, compression, contusion, ischemia, and stretching. Current literature suggests that the majority of perioperative nerve injuries are unrelated to regional anesthesia. Besides the blockade of sodium channels which is responsible for the anesthetic effect, systemic local anesthetics can have a positive influence on the inflammatory response and the hemostatic system in the perioperative period. However, next to these beneficial effects, local anesthetics exhibit time and dose-dependent toxicity to a variety of tissues, including nerves. There is equivocal experimental evidence that the toxicity varies among local anesthetics. Even though the precise order of events during local anesthetic-induced neurotoxicity is not clear, possible cellular mechanisms have been identified. These include the intrinsic caspase-pathway, PI3K-pathway, and MAPK-pathways. Further research will need to determine whether these pathways are non-specifically activated by local anesthetics, or whether there is a single common precipitating factor.

Anaesthetic management of cancer surgery may influence tumour recurrence. The modulation of gene expression by methylation of deoxyribonucleic acid (DNA) (epigenetics) is increasingly recognized as a major hallmark of cancer. Next to direct effects of local anaesthetics upon tumour cells, the ester-type local anaesthetic, procaine, has been shown to affect methylation status in several tumour cell lines, promoting the reactivation of tumour suppressor genes. We sought to determine whether the prototype amide-type local anaesthetic, lidocaine, influences the survival and epigenetic status of oestrogen receptor (ER)-positive and -negative breast cancer cell lines in vitro. Breast cancer cell lines BT-20 (ER-negative) and MCF-7 (ER-positive) were incubated with lidocaine and procaine as the reference substance. We performed cell count and determined apoptosis using TUNEL stain. Further, we assessed global methylation status, and methylation of three known tumour suppressor genes (RASSF1A, MYOD1, and GSTP1) using the MethyLight assay and real-time quantitative polymerase chain reaction, respectively. Baseline methylation was 100-fold higher in BT-20 cells. Here, we observed a dose-dependent decrease in DNA methylation in response to lidocaine (1, 0.01, and 0.01 mM) after 72 h (P<0.001, <0.001, and 0.004, respectively). The corresponding changes were smaller in MCF-7 cells. Global methylation status was profoundly influenced, but the methylation and mRNA expression status of three tumour suppressor genes was unchanged. Our findings suggest that demethylating tumour-suppressive effects of anaesthetic interventions may only be detectable in specific types of cancer due to differential methylation profiles. In conclusion, at clinically relevant concentrations, lidocaine demethylates DNA of breast cancer cell lines in vitro.

Background and objectives Laparoscopic hysterectomy is increasingly performed because it is associated with less postoperative pain and earlier recovery as compared with open abdominal hysterectomy. The aim of this systematic review was to evaluate the available literature regarding the management of pain after laparoscopic hysterectomy. Strategy and selection criteria Randomized controlled trials evaluating postoperative pain after laparoscopic hysterectomy published between January 1996 and May 2018 were retrieved, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, from the EMBASE and MEDLINE databases and the Cochrane Register of Controlled Trials. Efficacy and adverse effects of analgesic techniques were assessed. Results Of the 281 studies initially identified, 56 were included. Of these, 31 assessed analgesic or anesthetic interventions and 25 assessed surgical interventions. Acetaminophen, non-steroidal anti-inflammatory drugs, and dexamethasone reduced opioid consumption. Limited evidence hindered recommendations on alpha-2-agonists. Inconsistent evidence was found in the studies investigating pregabalin and transversus abdominis plane block, and no evidence was found for intraperitoneal local anesthetics, port site infiltration, or single-port laparoscopy. Measures to lower peritoneal insufflation pressure or humidify or heat insufflated gas seem to reduce the incidence of shoulder pain, but not abdominal pain. Conclusions The baseline analgesic regimen for laparoscopic hysterectomy should include acetaminophen, a non-steroidal anti-inflammatory drug, dexamethasone, and opioids as rescue analgesics.

Lidocaine demethylates deoxyribonucleic acid (DNA) in breast cancer cells. This modification of epigenetic information may be of therapeutic relevance in the perioperative period, because a decrease in methylation can reactivate tumour suppressor genes and inhibit tumour growth. The objectives of this study were to determine the effect of two amide local anaesthetics, ropivacaine and bupivacaine, on methylation in two breast cancer cell lines and to detect whether the combination of lidocaine with the chemotherapy agent 5-aza-2′-deoxycytidine (DAC) would result in additive demethylating effects. Breast cancer cell lines BT-20 [oestrogen receptor (ER)-negative] and MCF-7 (ER-positive) were incubated with lidocaine, bupivacaine, and ropivacaine to assess demethylating properties. Then, we tested varying concentrations of lidocaine and DAC to assess whether their demethylating effects were additive. Cell numbers and global methylation status were analysed. Lidocaine decreased methylation in BT-20 and MCF-7 cells, ropivacaine decreased methylation in BT-20 cells, and bupivacaine had no demethylating effect. When combined, lidocaine and DAC had additive demethylating effects. At clinically relevant doses, lidocaine and ropivacaine exert demethylating effects on specific breast cancer cell lines, but bupivacaine does not. The demethylating effects of lidocaine and DAC are indeed additive.