Complications of regional anesthesia

Complications of transvaginal radiofrequency ablation of fibroids: A 5-year experience

Introduction

Transvaginal radiofrequency ablation is a relatively noninvasive approach for the treatment of fibroids in patients who do not wish to undergo conventional surgery. Information on potential complications of this novel technique is very scarce.

Methods

Retrospective, descriptive, epidemiological study of 115 patients who underwent transvaginal radiofrequency ablation of fibroids and for whom complications were recorded.

Results

We performed 115 transvaginal radiofrequency ablation procedures, we recorded a total of 11 complications (9.6%; 95% CI, 3.8-14.8). Of these, 8 (7.0%) were classified as Clavien-Dindo type I, 1 (0.9%,) as type II, and 2 (1.7%) as type IIIb (severe). No other complications were recorded in a year follow-up.

Conclusion

Transvaginal radiofrequency ablation is a treatment option that makes it possible to treat fibroids that are difficult to manage using other techniques. Few associated complications have been described, and most of them are mild.

Bupivacaine as a euthanasia agent for African Clawed Frogs (Xenopus laevis)

Immersion in tricaine methanesulfonate (i.e. TMS) has been used for euthanasia of Xenopus laevis (African Clawed frogs). However, the time for preparation and potential human health hazards may pose as a barrier for large group culls. Here, we aimed to investigate whether immersion in bupivacaine is an effective means to euthanize this species. In experiment one, frogs (n = 10/group) were randomly assigned to 1-h immersion in 1 of 3 treatment groups: 1) TMS-5 (MS-222, 5g/L); 2) TMS-10 (MS-222, 10 g/L); or 3) Bupi-1.5 (0.5% Bupivacaine, 1.5 g/L). Frogs were then removed from solutions, rinsed with system water, and placed into a recovery cage. Heart rate was evaluated audibly via doppler ultrasound flow over 1 min at immediate removal (T1h), at 2 (T2h), and 3 (T3h) h in the recovery cage. In experiment two, frogs (n = 7/group) underwent 5-h & 19-h immersion in either TMS-5 or Bupi-1.5, with heart rate assessment at 5 and 19 hrs. Righting reflex and withdrawal reflex of the hindlimb were tested during the experiments. Experiment one-after the 1-h immersion, Bupi-1.5 treated animals had decreased heart rates compared to TMS-5 and TMS-10 treated animals by T2h. Neither TMS-5, TMS-10, nor Bupi-1.5 ceased heart rate after the 1-h immersion. Experiment two-after the 5-h immersion, Bupi-1.5 and TMS-5 treated animals were comparable in heart rates. 43% of TMS-5 animals and 14% of the Bupi-1.5 animals had completely ceased heart rates at T5h. At 19 h all remaining animals exhibited rigor mortis and had ceased heart rate. We recommend 19-h of immersion using either TMS-5 or Bupi-1.5 for cessation of heart rate in African Clawed frogs. These data are strong support for the use of secondary physical methods for euthanasia in African Clawed frogs when euthanasia by immersion is performed.

Interpectoral-pectoserratus plane (PECS II) block in patients undergoing trans-axillary thoracic outlet decompression surgery; A prospective double-blind, randomized, placebo-controlled clinical trial

STUDY OBJECTIVE

To investigate if an interpectoral-pectoserratus plane (PECS II) block decreases postoperative pain, postoperative nausea and vomiting and improves quality of recovery in patients with neurogenic thoracic outlet syndrome (NTOS) undergoing trans-axillary thoracic outlet decompression surgery.

DESIGN

A prospective single center double blinded randomized placebo-controlled trial.

SETTING

Perioperative period; operating room, post anesthesia care unit (PACU) and hospital ward.

PATIENTS

Seventy patients with NTOS, undergoing trans-axillary thoracic outlet decompression surgery.

INTERVENTIONS

Patients were randomized to an interventional arm, receiving the block with 40 ml ropivacaine 0.5% (concentration was adjusted if the patient's weight was <66 kg), and a placebo group, receiving a sham block with 40 ml NaCl 0.9%. The interpectoral-pectoserratus plane block was performed ultrasound guided; the first injection below the pectoral minor muscle and the second below the pectoral major muscle. The hospitals' pharmacist prepared the study medication and was the only person able to see the randomization result. The study was blinded for patients, researchers and medical personnel.

MEASUREMENTS

Primary outcome parameters were postoperative pain, measured by numeric rating scale on the PACU (start and end) and on the ward on postoperative day (POD) 0 and 1, and postoperative morphine consumption, measured on the PACU and on the ward during the first 24 h. Secondary outcome parameters were postoperative nausea and vomiting, and quality of recovery.

MAIN RESULTS

There was no statistically significant difference in NRS on the PACU at the start (ropivacaine 4.9 ± 3.2 vs placebo 6.2 ± 3.0, p = .07), at the end (ropivacaine 4.0 ± 1.7 vs placebo 3.9 ± 1.7, p = .77), on the ward on POD 0 (ropivacaine 4.6 ± 2.0 vs placebo 4.6 ± 2.0, p = 1.00) or POD 1 (ropivacaine 3.9 ± 1.8 vs placebo 3.6 ± 2.0, p = .53). There was no difference in postoperative morphine consumption at the PACU (ropivacaine 11.0 mg ± 6.5 vs placebo 10.8 mg ± 4.8, p = .91) or on the ward (ropivacaine 11.6 mg ± 8.5 vs placebo 9.6 mg ± 9.4, p = .39).

CONCLUSIONS

The interpectoral-pectoserratus plane block is not effective for postoperative analgesia in patients with NTOS undergoing trans-axillary thoracic outlet decompression surgery.

Immune response in breast cancer surgery. A comparative and prospective study of different anesthetic techniques

INTRODUCTION

The main reason for high mortality in breast cancer is local recurrence and metastasis, despite surgery as the first therapeutic option. The anesthesia used in the operation room can determine the immune response.

METHODS

A prospective, comparative and non- randomised study in patients undergoing breast cancer surgery was conducted in our hospital after obtaining approval from the Hospital's Institutional Review Board. Patients were divided in two groups: Group A received general anesthesia with propofol and opioids. Group B, in addition to general anesthesia, three interfascial blocks (Pec I, Pec II and BRILMA) were performed in all patients. Three blood samples were taken 1) previous anesthetic induction; 2) two hours after the end of the surgery and 3) 24-48 h after surgery. Leukocytes, CD3, CD4, CD8 and Natural Killer cells were determined at each time.

RESULTS

103 patients were included. 59 (group A) received general anesthesia and 54 (group B) general anesthesia and interfascial blocks. Regarding baseline characteristics, age was significantly higher in the group that received general anesthesia and mastectomy was more frequent in the group that received interfascial blocks. We observed after surgery an increase in leukocytes level that returns close to baseline levels. On the other hand, a reduction in the immune response was observed that also returns to the previous level 48 h after surgery. Group A and B get similar results and also subgroups of hormonal receptors (HER+, PR and/or ER+).

CONCLUSIONS

Interfascial blocks in chest wall added to general anesthesia in breast cancer surgery has not shown a significant difference in the inflammatory response or immunological depression compared to general anesthesia as the only anesthetic technique. It seems to trend less immunological depression in the interfascial block group.

Regional anesthesia for orthopedic procedures: What orthopedic surgeons need to know

Regional anesthesia is an integral component of successful orthopedic surgery. Neuraxial anesthesia is commonly used for surgical anesthesia while peripheral nerve blocks are often used for postoperative analgesia. Patient evaluation for regional anesthesia should include neurological, pulmonary, cardiovascular, and hematological assessments. Neuraxial blocks include spinal, epidural, and combined spinal epidural. Upper extremity peripheral nerve blocks include interscalene, supraclavicular, infraclavicular, and axillary. Lower extremity peripheral nerve blocks include femoral nerve block, saphenous nerve block, sciatic nerve block, iPACK block, ankle block and lumbar plexus block. The choice of regional anesthesia is a unanimous decision made by the surgeon, the anesthesiologist, and the patient based on a risk-benefit assessment. The choice of the regional block depends on patient cooperation, patient positing, operative structures, operative manipulation, tourniquet use and the impact of post-operative motor blockade on initiation of physical therapy. Regional anesthesia is safe but has an inherent risk of failure and a relatively low incidence of complications such as local anesthetic systemic toxicity (LAST), nerve injury, falls, hematoma, infection and allergic reactions. Ultrasound should be used for regional anesthesia procedures to improve the efficacy and minimize complications. LAST treatment guidelines and rescue medications (intralipid) should be readily available during the regional anesthesia administration.

Local and regional anaesthesia in dogs and cats: Overview of concepts and drugs (Part 1)

Pain management in veterinary patients is a crucial component of appropriate patient care. Multimodal analgesia that includes both systemically and locally/regionally administered drugs is generally the most effective approach to providing pain relief. Local anaesthetic drugs used in local and regional blockade are unique in that they can completely block the transmission of pain (in conscious patients) or nociceptive (in anaesthetized patients) signals, thereby providing profound analgesia. In addition, local and regional administration of drugs, when compared with systemic bolus administration, generally results in a lower incidence of dose‐related adverse effects. Due to the potential to provide profound analgesia and the high safety margin (when used correctly) of this drug class, local anaesthetics are recommended as part of the analgesic protocol in the majority of patients undergoing surgical procedures or suffering traumatic injuries. This manuscript, Part 1 of a two‐part instalment, emphasizes the importance of using local and regional anaesthesia as a component of multimodal analgesia, provides a review of the basic pharmacokinetics/pharmacodynamics of local anaesthetic drugs in general, lists information on commonly used local anaesthetic drugs for local and regional blockade in dogs and cats, and briefly introduces the novel liposome‐encapsulated bupivacaine (NOCITA®). Part 2 is a review of local and regional anaesthetic techniques used in dogs and cats (Grubb & Lobprise, 2020).

Benefits in radical mastectomy protocol: a randomized trial evaluating the use of regional anesthesia

Surgery is the first-line treatment for early, localized, or operable breast cancer. Regional anesthesia during mastectomy may offer the prevention of postoperative pain. One potential protocol is the combination of serratus anterior plane block (SAM block) with pectoral nerve block I (PECS I), but the results and potential benefits are limited. Our study compared general anesthesia with or without SAM block + PECS I during radical mastectomy with axillary node dissection and breast reconstruction using evaluations of pain, opioid consumption, side effects and serum levels of interleukin (IL)-1beta, IL-6 and IL-10. This is a prospective, randomized controlled trial. Fifty patients were randomized to general anesthesia only or general anesthesia associated with SAM block + PECS I (25 per group). The association of SAM block + PECS I with general anesthesia reduced intraoperative fentanyl consumption, morphine use and visual analog pain scale scores in the post-anesthetic care unit (PACU) and at 24 h after surgery. In addition, the anesthetic protocol decreased side effects and sedation 24 h after surgery compared to patients who underwent general anesthesia only. IL-6 levels increased after the surgery compared to baseline levels in both groups, and no differences in IL-10 and IL-1 beta levels were observed. Our protocol improved the outcomes of mastectomy, which highlight the importance of improving mastectomy protocols and focusing on the benefits of regional anesthesia.

A site check prior to regional anaesthesia to prevent wrong-sided blocks

This paper describes the implementation of the 'Stop Before You Block' (SB4YB) initiative in an Australian teaching hospital. This process, which began in the UK in 2010, is a pre-procedure pause to confirm the correct side of a regional anaesthetic block. A change in practice was implemented with the formal roll out of a SB4YB educational program. Use of the initiative was then audited over a subsequent three-month period. It was hoped that after implementing the initiative, at least 80% of blocks would have a site check performed. However, despite apparent support for the initiative, uptake was less than expected with only about 57% of blocks having a site check performed. A site check was less frequent if the block was done as an emergency procedure, outside of an operating theatre or by a locum or visiting anaesthetist. Our conclusion from the audit was that education is insufficient to promote a change in this practice. We propose that Stop Before You Block or a block time-out should be performed prior to all unilateral nerve blocks. Success of this initiative requires education, and both cultural and systems changes to occur. We propose that a formal block time-out should become part of the surgical safety checklist and this activity should be endorsed and promoted by anaesthetic professional bodies.

[Surgery on the wrong side: implication for the patient and the professional. Experience in a Major Ambulatory Surgery of the Foot Unit]

Surgery of the wrong side is a very uncommon complication in orthopaedic surgery, but with serious consequences for the patient, the surgeon and the health institution, having to put all the necessary measures in place to prevent this occurring. We have conducted a prospective study on the introduction of a protocol to prevent surgery of the wrong side in 101 patients operated on for any foot disease in the Major Surgery Ambulatory Unit, performing three independent controls to verify the side: by the patient, by the nurse and by the anaesthetist. We review the information available of the side in the medical records and their correlation with the side operated on. Almost a quarter of the patients, 24.8%, were not informed that they had to make a mark on the foot to be operated on. No mark was made by 18.4% of the patients informed to do so, with no relationship between age, gender, education level, to live alone or previous foot operations. There was a lack of noting the side in the documentation, with this omission being more frequent in the Orthopaedic and Traumatology and Anaesthesiology medical records. Nine cases of inconsistency in the surgical side were detected, all in patients who had previous surgery in any foot. Marking of the side has been incorporated as routine practice in foot surgery, being beneficial for the safety of the patient, and should become normal practice in all surgical areas in the near future.

Management and treatment of local anaesthetic toxicity

Local anaesthetics have been used within surgical practice since the late 1800s, when the ophthalmologist Carl Koller discovered the tissue numbing properties of cocaine (Odedra & Lyons 2010). Since that time, the ongoing development of anaesthetic drugs has provided many different local anaesthetics (LA) to clinical practice. The techniques for using these drugs in surgical practice have also developed, shaping the modern practices we know today. Increasing numbers of surgical procedures are now carried out under LA that once necessitated general anaesthetic, for example carotid endarterectomy as first described by Eastcott et al (1954). This type of procedure can now be safely carried out under LA but does require a large volume of the drug (up to 25 mls, see Table 1 for variations) to infiltrate a very vascular surgical field, and the LA may need supplementing during surgery (AIIman & Wilson 2006). The practice of routinely injecting large volumes of LA agents into surgical wounds to aid post-operative pain control also increases the risk of inadvertent intravascular injection that couldlead to LA toxicity (Parker et al 2009).

Clinical utility of low-volume ultrasound-guided interscalene blockade: contraindications reconsidered

OBJECTIVE

The purpose of this series is to describe cases in which ultrasound guidance was used to allow patients to receive the benefits of regional anesthesia while safely circumventing traditional contraindications to interscalene blockade (ISB).

METHODS

Targeted low-volume ISB was performed in 3 patients in whom this procedure would typically be contraindicated because of phrenic nerve blockade or risk of local anesthetic toxicity. A patient with severe respiratory dysfunction, a patient undergoing bilateral shoulder surgery, and a patient requiring awake fiberoptic intubation underwent low-volume ultrasound-guided ISB. The ultrasound technique involved the use a low local anesthetic volume, anatomic identification of the brachial plexus trunk, needle placement opposite the phrenic nerve position, and control over local anesthetic spread.

RESULTS

In both patients in whom diaphragmatic paralysis was a concern, postoperative respiratory parameters indicated successful regional analgesia without evidence of phrenic nerve blockade. In the patient requiring an additional regional anesthetic procedure, ISB was performed with a local anesthetic volume low enough to avoid exceeding toxic safety thresholds.

CONCLUSIONS

Although further studies are warranted, we report on 3 cases in which ultrasound guidance was used to allow patients to receive the benefits of regional anesthesia while safely avoiding standard contraindications to ISB. Ultrasound technology may allow providers to perform low-volume brachial plexus blockade while avoiding issues related to phrenic nerve blockade and systemic local anesthetic toxicity.

The toxicity of local anesthetics: the place of ropivacaine and levobupivacaine

PURPOSE OF REVIEW

Ropivacaine and levobupivacaine were developed after evidence of bupivacaine-related severe toxicity. Despite a comparable analgesic profile, quantitative differences become evident with regard to their specific rate of systemic toxicity. The present article provides a concise review of the toxic potencies of levobupivacaine and ropivacaine.

RECENT FINDINGS

As lipophilicity is known to be a major determinant in local anesthetic toxicity, the clinical safety profile of ropivacaine seems to be more favorable than that of levobupivacaine. Experimental studies and case reports confirm this hypothesis, showing that ropivacaine is characterized by fewer (cardio) toxic effects and, most probably, a greater margin of safety. Both agents also may dose dependently damage neurons and skeletal muscle tissue at the injection site. Although their specific rate of neurotoxicity appears to be rather low, levobupivacaine is characterized by an outstanding myotoxic potential.

SUMMARY

Compared with bupivacaine, both agents may be considered as 'more well tolerated' but not as 'totally well tolerated', as they are still capable of inducing systemic and local toxicity. However, ropivacaine seems to have the greatest margin of safety of all long-acting local anesthetics at present.