Local anesthesia for infrainguinal arterial reconstruction

Utilization and Outcomes of Local Anesthesia and Peripheral Nerve Block for Hybrid Lower Extremity Revascularization

Purpose: To investigate the utilization of local anesthesia or peripheral nerve block with monitored anesthesia care (LPMAC) and its impact on the perioperative outcomes of hybrid lower extremity revascularization (LER) compared with general anesthesia (GA). Materials and Methods: A search of the ACS-NSQIP database between 2005 and 2017 identified 9430 patients who underwent hybrid LER for peripheral artery disease. Excluding 449 ineligible cases left 8981 hybrid LER patients for analysis. The patients were dichotomized based on the anesthetic technique: 8631 (96.1%) GA and 350 (3.9%) LPMAC. The GA patients were matched 3:1 based on propensity scores to patients in the LPMAC group based on gender, age, race, functional status, transfer status, chronic obstructive pulmonary disease (COPD), dialysis status, American Society of Anesthesiologists (ASA) class, emergent surgery, preoperative sepsis, indication, and type of open and endovascular procedure. Outcomes including complications, mortality, procedure time, and hospital length of stay were compared between the matched groups (801 GA vs 267 LPMAC). Results: Comparing the unmatched groups, those treated under LPMAC were older (72.7±9 vs 68±8.4 years, p<0.001) and had higher rates of COPD (24.3% vs 17%, p=0.001), dialysis dependence (8.1% vs 4.2%, p=0.002), preoperative sepsis (6.6% vs 4.2%, p=0.029), and ASA class ≥IV (29.1% vs 24.1%, p=0.036) than in the unmatched GA cohort. In the matched comparison, LPMAC was associated with lower overall morbidity (25.5% vs 32.3%, p=0.042) and shorter operating time (202.7±98 vs 217.7±102 minutes, p=0.034) compared with GA. The rate of myocardial infarction was lower (1.1% vs 2.4%) and ventilator use for >48 hours was less frequent (0.4% vs 2.6%) for LPMAC patients, though statistical significance was not reached. There was no difference in mortality or hospital length of stay. Conclusion: LPMAC is an infrequent anesthetic technique for hybrid LER and is primarily used for patients with a high burden of comorbidities. LPMAC is associated with reduced overall morbidity and operating time. Further studies are needed to identify which patients undergoing hybrid LER benefit most from LPMAC.

Estimated Maximal Safe Dosages of Tumescent Lidocaine

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Published ahead of print February 18, 2016

BACKGROUND:

Tumescent lidocaine anesthesia consists of subcutaneous injection of relatively large volumes (up to 4 L or more) of dilute lidocaine (≤1 g/L) and epinephrine (≤1 mg/L). Although tumescent lidocaine anesthesia is used for an increasing variety of surgical procedures, the maximum safe dosage is unknown. Our primary aim in this study was to measure serum lidocaine concentrations after subcutaneous administration of tumescent lidocaine with and without liposuction. Our hypotheses were that even with large doses (i.e., >30 mg/kg), serum lidocaine concentrations would be below levels associated with mild toxicity and that the concentration-time profile would be lower after liposuction than without liposuction.

METHODS:

Volunteers participated in 1 to 2 infiltration studies without liposuction and then one study with tumescent liposuction totally by local anesthesia. Serum lidocaine concentrations were measured at 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, and 24 hours after each tumescent lidocaine infiltration. Area under the curve (AUC∞) of the serum lidocaine concentration-time profiles and peak serum lidocaine concentrations (Cmax) were determined with and without liposuction. For any given milligram per kilogram dosage, the probability that Cmax >6 μg/mL, the threshold for mild lidocaine toxicity was estimated using tolerance interval analysis.

RESULTS:

In 41 tumescent infiltration procedures among 14 volunteer subjects, tumescent lidocaine dosages ranged from 19.2 to 52 mg/kg. Measured serum lidocaine concentrations were all <6 μg/mL over the 24-hour study period. AUC∞s with liposuction were significantly less than those without liposuction (P = 0.001). The estimated risk of lidocaine toxicity without liposuction at a dose of 28 mg/kg and with liposuction at a dose of 45 mg/kg was ≤1 per 2000.

CONCLUSIONS:

Preliminary estimates for maximum safe dosages of tumescent lidocaine are 28 mg/kg without liposuction and 45 mg/kg with liposuction. As a result of delayed systemic absorption, these dosages yield serum lidocaine concentrations below levels associated with mild toxicity and are a nonsignificant risk of harm to patients.

Lower extremity bypass with tumescent local anesthesia

Lower extremity bypass is most commonly performed for the treatment of critical limb ischemia. These patients often pose high surgical risk secondary to significant clinical comorbidities. These risks may be compounded when general anesthesia is considered. We present the case of a patient at high anesthesia risk with critical limb ischemia who was unable to receive general anesthesia or neuraxial blockade. An infrainguinal bypass was performed using tumescent anesthesia with minimal intravenous sedation. The patient was discharged 6 days later, and his postoperative course was complicated by a groin lymphocele. Tumescent local anesthesia is a possible alternative pain management strategy for patients undergoing lower extremity bypass surgery.

Neuraxial anaesthesia for lower-limb revascularization

BACKGROUND

Lower-limb revascularization is a surgical procedure that is performed to restore an adequate blood supply to the limbs. Lower-limb revascularization surgery is used to reduce pain and sometimes to improve lower-limb function. Neuraxial anaesthesia is an anaesthetic technique that uses local anaesthetics next to the spinal cord to block nerve function. Neuraxial anaesthesia may lead to improved survival. This systematic review was originally published in 2010 and was first updated in 2011 and again in 2013.

OBJECTIVES

To determine the rates of death and major complications associated with spinal and epidural anaesthesia as compared with other types of anaesthesia for lower-limb revascularization in patients aged 18 years or older who are affected by obstruction of lower-limb vessels.

SEARCH METHODS

The original review was published in 2010 and was based on a search until June 2008. In 2011 we reran the search until February 2011 and updated the review. For this second updated version of the review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, LILACS, CINAHL and Web of Science from 2011 to April 2013.

SELECTION CRITERIA

We included randomized controlled trials comparing neuraxial anaesthesia (spinal or epidural anaesthesia) versus other types of anaesthesia in adults (18 years or older) with arterial vascular obstruction undergoing lower-limb revascularization surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed data extraction and assessed trial quality. We pooled the data on mortality, myocardial infarction, lower-limb amputation and pneumonia. We summarized dichotomous data as odds ratio (OR) with 95% confidence interval (CI) using a random-effects model.

MAIN RESULTS

In this updated version of the review, we found no new studies that met our inclusion criteria. We included in this review four studies that compared neuraxial anaesthesia with general anaesthesia. The total number of participants was 696, of whom 417 were allocated to neuraxial anaesthesia and 279 to general anaesthesia. Participants allocated to neuraxial anaesthesia had a mean age of 67 years, and 59% were men. Participants allocated to general anaesthesia had a mean age of 67 years, and 66% were men. Four studies had an unclear risk of bias. No difference was observed between participants allocated to neuraxial or general anaesthesia in mortality rate (OR 0.89, 95% CI 0.38 to 2.07; 696 participants; four trials), myocardial infarction (OR 1.23, 95% CI 0.56 to 2.70; 696 participants; four trials), and lower-limb amputation (OR 0.84, 95% CI 0.38 to 1.84; 465 participants; three trials). Pneumonia was less common after neuraxial anaesthesia than after general anaesthesia (OR 0.37, 95% CI 0.15 to 0.89; 201 participants; two trials). Evidence was insufficient for cerebral stroke, duration of hospital stay, postoperative cognitive dysfunction, complications in the anaesthetic recovery room and transfusion requirements. No data described nerve dysfunction, postoperative wound infection, patient satisfaction, postoperative pain score, claudication distance and pain at rest.

AUTHORS' CONCLUSIONS

Available evidence from included trials that compared neuraxial anaesthesia with general anaesthesia was insufficient to rule out clinically important differences for most clinical outcomes. Neuraxial anaesthesia may reduce pneumonia. No conclusions can be drawn with regard to mortality, myocardial infarction and rate of lower-limb amputation, or less common outcomes.

Proximal direct endarterectomy combined with simultaneous distal endovascular therapy for chronic full-length occlusion of the superficial femoral artery in elderly patients

BACKGROUND AND PURPOSE

The most proximal ostial site of the chronic occlusive superficial femoral artery is not suitable for ballooning or stenting because the deep femoral artery may be occluded by these procedures. Thus, the feasibility of performing an open endarterectomy for the occluded ostium of the superficial femoral arteries combined with an endovascular therapy for the remaining distal site was evaluated.

METHODS

Eleven critically ischemic limbs in 10 elderly patients with poor general health were enrolled. They had full-length occlusion of the superficial femoral artery involving its ostium. The ostial site was managed with an open endarterectomy followed by endovascular therapy for the remaining distal site.

RESULTS

All procedures were successfully performed. All patients experienced pain relief, and the wounds healed. During the follow-up observation period (average: 23.9 ± 14.7 months), nine patients died. None of the patients, including those who had lost patency of the superficial femoral artery, received major amputation.

CONCLUSION

Elderly patients, including those who were in terminal stage, were able to withstand the operation, and their postoperative quality of life was not compromised. Although the patency following the surgery was limited, sparing the deep femoral artery could either prevent or delay the recurrence of critical limb ischemia.

Regional anesthesia for vascular surgery

Vascular surgical patients are a diverse group of patients who tend to be elderly, with multiple comorbidities, while vascular procedures may involve significant blood loss and ischemia of tissues beyond the arterial obstruction. Regional anesthesia techniques may offer benefits to patients undergoing vascular surgery because of their cardiorespiratory comorbidities. However, this group of patients is commonly receiving multiple medications, including anticoagulants, so regional techniques are not without risks. This review will discuss this topic based around 3 fundamental revascularization procedures, carotid, abdominal aortic aneurysm repair, and infrainguinal surgery, discussing the clinical applications of regional techniques relevant to each key area.

Axillofemoral bypass with local anesthesia: a way forward to enable limb salvage in high-risk patients

For an active, ambulant patient with critical, lower limb ischemia, amputation can lead to a poor quality of life. A small group of older people with critical limb ischemia are considered at high risk for revascularization under conventional anesthesia owing to their comorbid conditions. In these cases, when endovascular therapy is not an option, the decision to amputate or revascularize presents a dilemma, especially in ambulant patients. In this article, we present 2 cases in which the individuals had diabetic foot gangrene, rest pain, and multiple comorbidities, and were unfit to undergo conventional anesthesia. In addition, they had severe aortoiliac occlusive disease, which cannot be managed by endovascular methods. Both patients were living independently and were ambulant before their foot ulcer and ischemia. They underwent an axillofemoral bypass under local anesthesia. The postoperative course was uneventful. After a 3-year follow-up, both patients continue to be ambulant and have no complaints. With selective use of local anesthetic techniques, surgical teamwork to shorten the procedure time, and close meticulous postoperative care, an axillofemoral bypass can enable limb salvage for ambulant patients who are considered unfit for conventional anesthesia.

Neuraxial anaesthesia for lower-limb revascularization

BACKGROUND

Lower-limb revascularization surgery is used to reduce pain and sometimes to improve lower-limb function. The type of anaesthesia used during lower-limb revascularization may affect the risks of both good and bad outcomes.

OBJECTIVES

To determine the rates of death and major complications with spinal and epidural anaesthesia compared with other types of anaesthesia for lower-limb revascularization.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2008, Issue 2); MEDLINE (1960 to 10th June 2008); EMBASE (1982 to 10th June 2008); LILACS (1982 to 10th June 2008); CINAHL (1982 to 10th June 2008) and ISI Web of Science (1900 to 10th June 2008).

SELECTION CRITERIA

We included randomized controlled trials that evaluated the effect of anaesthetic type in adults aged 18 years or older undergoing lower-limb revascularization surgery.

DATA COLLECTION AND ANALYSIS

Two authors independently performed the data extraction. Primary outcomes were mortality, cerebral stroke, myocardial infarction, nerve dysfunction and postoperative lower-limb amputation rate. The secondary outcome analysed was pneumonia. We judged risk of bias with four criteria: randomization and allocation concealment methods, blinding of treatment and outcome assessment and completeness of follow up. To assess heterogeneity we used the I(2) statistic. We summarized dichotomous data as odds ratio (OR) with 95% confidence interval (CI) using a random-effects model.

MAIN RESULTS

We included four studies that compared neuraxial anaesthesia with general anaesthesia. The total number of participants was 696, of whom 417 were allocated to neuraxial anaesthesia and 279 to general anaesthesia. Participants allocated to neuraxial anaesthesia had a mean age of 67 years and 59% were men. Participants allocated to general anaesthesia had a mean age of 67 years and 66% were men. There was no difference between participants allocated to neuraxial or general anaesthesia in: mortality rate (OR 0.89, 95% CI 0.38 to 2.07; 696 participants, four trials); myocardial infarction (OR 1.23, 95% CI 0.56 to 2.70; 696 participants, four trials); and lower-limb amputation rate (OR 0.84, 95% CI 0.38 to 1.84; 465 participants, three trials). Pneumonia was less common following neuraxial anaesthesia than general anaesthesia (OR 0.37, 95% CI 0.15 to 0.89; 201 participants, two trials).

AUTHORS' CONCLUSIONS

There was insufficient evidence available from the included trials that compared neuraxial anaesthesia with general anaesthesia to rule out clinically important differences for most clinical outcomes. Neuraxial anaesthesia may reduce pneumonia. No conclusions can be drawn with regard to mortality, myocardial infarction and rate of lower-limb amputation or less common outcomes.

Preoperative assessment and management to prevent complications during high-risk vascular surgery

OBJECTIVE

Most patients requiring vascular surgical reconstruction are at high risk for major morbidity and mortality, with certain vascular procedures at particularly high risk for complications. Although numerous comorbid conditions are precisely the risk factors that determine outcome, we review particular factors for each surgery that may be optimized to alter outcome and minimize postoperative complications.

DESIGN

Literature review.

RESULTS

Certain aspects of care are common to all vascular surgery procedures, including thoracoabdominal aortic aneurysm repair, pararenal and ruptured abdominal aortic aneurysm repair, mesenteric and renal revascularization, and carotid endarterectomy. Some factors that are important include careful preoperative assessment and optimization of cardiac, pulmonary, and renal function and volume status. In addition, the use of experienced teams during and after the procedure, as well as clear and continuous communication between all surgical team members, may improve outcome. Particular attention to procedural details is also crucial to achieving excellent results.

CONCLUSIONS

Patients needing vascular surgery often possess management challenges that increase the risk of perioperative complications. Meticulous attention to details during all phases of care, including preoperative optimization as well as intraoperative procedural conduct and communication, helps achieve optimal results and thus minimize the risk of complications.