Periphere Regionalanästhesie beim Patienten in Allgemeinanästhesie

Comparison of the Analgesic Effect of Pericapsular Nerve Group Block and Lumbar Erector Spinae Plane Block in Elective Hip Surgery

Background and Objectives: The aim of this study was to compare the effectiveness of pericapsular nerve group (PENG) and lumbar erector spinae plane (L-ESP) blocks, both administered with a high volume (40 mL) of local anesthetic (LA), for multimodal postoperative analgesia in patients undergoing hip surgery. Materials and Methods: This was a prospective, double-blind, randomized study that included 75 adult patients who were divided into three equal groups: control, PENG, and L-ESP. The study compared pain intensity, morphine consumption, time to first morphine request, and postoperative satisfaction between the control group, which received standard multimodal analgesia, and the block groups, which received PENG or L-ESP block in addition to multimodal analgesia. The numerical rating scale (NRS) was used to measure pain intensity. Results: The results showed that the block groups had lower pain intensity scores and morphine consumption, a longer time to the first morphine request, and higher postoperative satisfaction compared to the control group. The median maximum NRS score during the first 12 h was four in the control group, two in the PENG group, and three in the L-ESP group. The control group (21.52 ± 9.63 mg) consumed more morphine than the two block groups (PENG, 11.20 ± 7.55 mg; L-ESP, 12.88 ± 8.87 mg) and requested morphine 6.8 h earlier and 5 h earlier than the PENG and L-ESP groups, respectively. The control group (median 3) had the lowest Likert satisfaction scores, while the PENG group (median 4) had the lowest NRS scores (L-ESP, median 4). Conclusions: The application of PENG or L-ESP blocks with high-volume LA in patients undergoing hip surgery reduces the need for postoperative analgesia and improves the quality of multimodal analgesia.

Timing of Transversus Abdominis Plane Block and Postoperative Pain Management

Background

Transversus abdominis plane (TAP) blocks using liposomal bupivacaine can reduce postoperative pain and opioid consumption after surgery. The impact of timing of administration of such blocks has not been determined.

Materials and Methods

A retrospective cohort study of all adult patients that underwent colorectal procedures between January 2013 and October 2015 and received TAP blocks with liposomal bupivacaine at our institution was conducted. The primary outcomes were postoperative pain scores and opioid consumption. Secondary outcomes included postoperative use of non-opioid analgesics as well as total hospital cost of admission and postoperative hospital length of stay.

Results

A total of 287 patients were identified and included in the analysis. A total of 71 patients received blocks prior to induction of general anesthesia (pre-ind), 85 patients received blocks after induction of general anesthesia but prior to surgical incision (post-ind) and 131 patients received blocks after completion of surgery (post-op). No significant differences were observed in the postoperative pain scores (either in the first 4 hours or for the entire duration of hospital stay) or opioid consumption between the pre-ind and the post-ind groups. More ketorolac was used in the post-op group compared to the pre-ind group (or= 3.36, 95% CI (1.08, 10.43); p=0.03).

Conclusion

Our findings suggest that there seems to be no difference if tap blocks with liposomal bupivacaine are performed before or after induction of anesthesia. Patient preference as well as operating room efficiency should be considered when deciding on the timing of these blocks.

Guidelines for the safe clinical practice of peripheral nerve blocks in the adult patient

The Peripheral Nerve Block working group of the Belgian Association for Regional Anesthesia has revised and updated the “Clinical guidelines for the practice of peripheral nerve block in the adult” which were published in 2013.

Combination Preemptive Peripheral Nerve Block in Limb Surgery. A Prospective Study

Background and objectives: Patients often suffer from moderate to severe pain during the early recovery period in orthopedic surgery. We investigated the impact of a single-shot preoperative peripheral nerve block (PNB) on post-anesthesia recovery parameters and interleukin (IL)-6 level during limb surgery. Materials and Methods: A prospective randomized controlled study was conducted, and patients scheduled for limb surgery were recruited. Sixty patients were randomly assigned to either the PNB group or control group, who received morphine as a primary analgesic. The peak verbal numeric rating scale (NRS) score in the post-anesthesia care unit (PACU) was evaluated as a primary outcome. We also recorded rescue analgesics requirement and wake-up time from anesthesia in the PACU. In addition, the change of plasma IL-6 level after incision was measured. Results: Fifty-two patients completed the study, 27 and 25 cases in the PNB and control group, respectively. Preemptive PNB significantly reduced peak NRS score in the PACU compared to control group. Lower rescue analgesics requirement and rapid wake-up from anesthesia were also noted in PNB group. The IL-6 concentration increased less in the PNB group at 2 h after incision. Conclusions: Preemptive PNB attenuates IL-6 expression 2 h after incision and improves pain management in the PACU. PNB was considered as an essential part of pain management in limb surgery.

Update on Direct Oral AntiCoagulants (DOACs)

Recent findings require an update of previous recommendations for the perioperative use of Direct Oral AntiCoagulants (DOACs). A break in preoperative treatment of 24-96 hours is recommended based on the pharmacokinetic profiles of DOACs and depends on individual patient characteristics, their renal and possibly liver function, and their surgery-related risk of bleeding. In cases of renal or hepatic insufficiency, whether to extend the preoperative interruption of IIa- and Xa-inhibitors is a clinical decision that must be reached on an individual patient basis. In cases of epidural or spinal anaesthesia, more conservative pausing-intervals are recommended due to the risk of persistent neurologic deficits (e.g., paraplegia) following the development of spinal subdural and epidural haematomas. Elective surgery should be postponed according to these recommendations. Preoperative "bridging" with LMWH (more precisely referred to as "switching") should be omitted due to a significantly increased risk of bleeding. In addition, the incidence of perioperative thromboembolic risks, such as DVT, PE, and stroke, are no different whether interruption or "switching" is undertaken. Postoperatively, the DOACs can be reinstituted within the first 24 hours. In cases of major surgery or if there is a higher risk of bleeding, resumption of DOACS should only begin after 24-72 hours. In patients with an elevated thromboembolic risk, transient postoperative LMWH administration can be recommended during this period.Interaction of DOACs with other drugs usually occurs during the absorption, transport and elimination of these drugs. Therefore, substance- specific restrictions and recommendations should be observed during these times. In everyday clinical practice, webbased, independent information portals on drug-interactions are very helpful in providing safe and rapid information about potential interactions when DOACs are used in combination with other drugs, especially during perioperative management.Non-adherence to medications is a worldwide problem that has dangerous and costly consequences. Present data suggest that persistence is the primary factor that supports adherence. Despite the adherence data presented in the DOACS approval studies (e.g., persistence in the treatment of acute venous thromboembolism has been reported to be between 94-99%), the first registries and meta-analyses provide sobering results regarding the incidence of persistence and the success rate of interventions designed to improve adherence with DOACs in cases of long-term usage.

Nerve growth factor loaded heparin/chitosan scaffolds for accelerating peripheral nerve regeneration

Artificial chitosan scaffolds have been widely investigated for peripheral nerve regeneration. However, the effect was not as good as that of autologous grafts and therefore could not meet the clinical requirement. In the present study, the nerve growth factor (NGF) loaded heparin/chitosan scaffolds were fabricated via electrostatic interaction for further improving nerve regeneration. The physicochemical properties including morphology, wettability and composition were measured. The heparin immobilization, NGF loading and release were quantitatively and qualitatively characterized, respectively. The effect of NGF loaded heparin/chitosan scaffolds on nerve regeneration was evaluated by Schwann cells culture for different periods. The results showed that the heparin immobilization and NGF loading did not cause the change of bulk properties of chitosan scaffolds except for morphology and wettability. The pre-immobilization of heparin in chitosan scaffolds could enhance the stability of subsequently loaded NGF. The NGF loaded heparin/chitosan scaffolds could obviously improve the attachment and proliferation of Schwann cells in vitro. More importantly, the NGF loaded heparin/chitosan scaffolds could effectively promote the morphology development of Schwann cells. The study may provide a useful experimental basis to design and develop artificial implants for peripheral nerve regeneration and other tissue regeneration.

Pathophysiology and Etiology of Nerve Injury Following Peripheral Nerve Blockade

This review synthesizes anatomical, anesthetic, surgical, and patient factors that may contribute to neurologic complications associated with peripheral nerve blockade. Peripheral nerves have anatomical features unique to a given location that may influence risk of injury. Peripheral nerve blockade-related peripheral nerve injury (PNI) is most severe with intrafascicular injection. Surgery and its associated requirements such as positioning and tourniquet have specific risks. Patients with preexisting neuropathy may be at an increased risk of postoperative neurologic dysfunction. Distinguishing potential causes of PNI require clinical assessment and investigation; a definitive diagnosis, however, is not always possible. Fortunately, most postoperative neurologic dysfunction appears to resolve with time, and the incidence of serious long-term nerve injury directly attributable to peripheral nerve blockade is relatively uncommon. Nonetheless, despite the use of ultrasound guidance, the risk of block-related PNI remains unchanged.

WHAT'S NEW

Since the 2008 Practice Advisory, new information has been published, furthering our understanding of the microanatomy of peripheral nerves, mechanisms of peripheral nerve injection injury, toxicity of local anesthetics, the etiology of and monitoring methods, and technologies that may decrease the risk of nerve block-related peripheral nerve injury.

Local Anaesthetic Systemic Toxicity in a Patient under General Anaesthesia (GA): A Diagnostic Challenge

Local anaesthetic systemic toxicity (LAST) is one of the most dreadful complications after local anaesthetic (LA) use and it is very difficult to manage. The diagnosis of LAST is purely clinical and its presentation is usually obscured in a sedated or anaesthetized patient. A 25-year-old male patient undergoing laparotomy for acute duodenal perforation under general anaesthesia developed seizures after epidural administration of 0.5% bupivacaine. All other possible causes of seizures were ruled out. Seizures were controlled with antiepileptic drugs and patient recovered fully after withholding LA administration. Although, lipid rescue is recommended for LAST, our patient was managed without its use. We, therefore, recommend that utmost care and vigilance should be exercised while using local anesthetics as there is no perfectly accurate method to rule out intravascular administration of LA. Even, if LA is correctly used, LA is detected in plasma due to its systemic absorption from injection site.