Epidural versus general anesthesia for infrainguinal arterial reconstruction

Anesthetic management for lower extremity vascular bypass procedures: The impact of general or regional anesthesia on clinical outcomes

PURPOSE

Postoperative complications after major surgery, especially vascular procedures, are associated with a significant increase in costs and mortality. Previous studies evaluating general anesthesia versus regional or neuraxial anesthesia for infrainguinal bypass have produced conflicting results. The main aim of the present study is to review current evidence on the application of regional or general anesthesia in patients undergoing infrainguinal bypass surgery and its potential favorable effects on postoperative outcomes.

CONTENTS

Patients undergoing vascular surgery often have multiple comorbidities, and it is important to outline both benefits and risks of regional anesthesia techniques. Neuraxial anesthesia in vascular surgery allows overall avoidance of general anesthesia and does provide short-term benefits beyond analgesia. Previous observational studies suggest that neuraxial anesthesia for lower limb revascularization may reduce morbidity and length of stay. However, evidence of long-term benefits is lacking in most procedures and further work is still warranted.

CONCLUSIONS

Neuraxial anesthesia is usually an effective anesthesia technique for infrainguinal bypass surgery. Elderly patients and those with underlying respiratory problems may display some benefit from neuraxial anesthesia. Further evaluation within institutions should be performed to identify which patients would most benefit from regional techniques. Notably, systemic antithrombotic and anticoagulation therapy is common among this population and may affect anesthetic choices.

A framework for perioperative care for lower extremity vascular bypasses: A Consensus Statement by the Enhanced Recovery after Surgery (ERAS®) Society and Society for Vascular Surgery

The Society for Vascular Surgery and the Enhanced Recovery After Surgery (ERAS) Society formally collaborated and elected an international, multi-disciplinary panel of experts to review the literature and provide evidence-based suggestions for coordinated perioperative care for patients undergoing infrainguinal bypass surgery for peripheral artery disease. Structured around the ERAS core elements, 26 suggestions were made and organized into preadmission, preoperative, intraoperative, and postoperative sections.

Outcomes After Neuraxial or Regional Anaesthesia Instead of General Anaesthesia for Lower Limb Revascularisation Surgery: A Systematic Review and Meta-Analysis of Randomised and Non-Randomised Studies

OBJECTIVE

To determine whether receipt of neuraxial or regional anaesthesia instead of general anaesthesia for lower limb revascularisation surgery affects patient outcomes.

DATA SOURCES

MEDLINE, EMBASE, Evidence Based Medicine Reviews, and Google Scholar.

REVIEW METHODS

After protocol registration, the data sources were searched for randomised and non-randomised studies comparing neuraxial or regional anaesthesia with general anaesthesia for lower limb revascularisation surgery in adults. Two investigators independently selected articles, extracted data, and assessed risks of bias. Data were pooled using random effects models. GRADE was used to assess certainty in cumulative evidence.

RESULTS

From 10 755 citations identified, five randomised (n = 970) and 13 non-randomised (n = 96 800) studies were included. Use of neuraxial instead of general anaesthesia for lower limb revascularisation surgery was associated with no statistically significant reduction in short term (in hospital or 30 day) mortality in randomised studies (pooled odds ratio [OR] 0.77; 95% confidence interval [CI] 0.33 - 1.81; low certainty) and a statistically significant reduction in adjusted short term mortality in non-randomised studies (pooled OR 0.67; 95% CI 0.56 - 0.81; low certainty). Adults allocated to neuraxial anaesthesia in randomised studies had fewer pulmonary complications (pooled OR 0.35; 95% CI 0.16 - 0.76; low certainty). In non-randomised studies, neuraxial instead of general anaesthesia was associated with a lower adjusted odds of any morbidity (pooled OR 0.66; 95% CI 0.52 - 0.84), cardiac complications (pooled OR 0.68; 95% CI 0.58 - 0.79), pneumonia (pooled OR 0.81; 95% CI 0.64 - 1.02), prolonged mechanical ventilation (OR 0.09; 95% CI 0.002 - 0.55), and bypass graft thrombosis (OR 0.70; 95% CI 0.59 - 0.85), as well as a shorter operative duration (low certainty for all). Use of a nerve block instead of general anaesthesia was associated with a lower adjusted odds of delirium (OR 0.16; 95% CI 0.06 - 0.42) and a shorter operative duration (low certainty for both).

CONCLUSION

Randomised and non-randomised data suggest that neuraxial anaesthesia for lower limb revascularisation surgery reduces morbidity and possibly mortality. Until randomised trials with a low risk of bias become available, this study supports use of neuraxial anaesthesia for these procedures where appropriate.

Modern Lower Extremity Bypass Outcomes by Anesthesia Type in the Veteran Population

BACKGROUND

Lower extremity bypass (LEB) revascularization can be performed under general (GA) or neuraxial anesthesia (NA). Studies show that the use of NA may decrease morbidity, 30-day mortality, and hospital length-of-stay (LOS). The goal of our analysis is to examine the differences in postsurgical outcomes following LEB between patients who undergo GA compared to NA in the Veteran Affairs Surgical Quality Improvement Program (VASQIP) database.

METHODS

After IRB approval, the VASQIP database was assessed for patients who underwent LEB between 1998-2018. Only infrainguinal bypass procedures and anesthesia type classified as "general," "epidural," or "spinal" were included. The neuraxial cohort includes both spinal and epidural anesthesia patients. The Risk Analysis Index (RAI), a validated measure of frailty, was additionally calculated for each patient. Chi squared, paired t-test, and binary logistic regression were used to compare the cohorts.

RESULTS

During this period, 22,960 veterans underwent LEB recorded in VASQIP. Compared to those who underwent surgery under GA, patients with procedures performed using NA were older (66.4 ± 9.6 years vs. 65.3 ± 9 years respectively; P <0.001) and more frail (average RAI score 25.7 ± 7.0 vs. 24.9 ± 6.7; P < 0.001). Operative time was shorter in the NA group (4.1 ± 1.7 hrs vs. 4.7 ± 3.0 hrs; P < 0.001) and fewer cases were emergent (1.55% vs. 4.13%; P <0.001). Patients in the GA group had higher rates of postoperative prolonged ileus (0.31% vs. 0.00%; P = 0.03), pneumonia (1.60% vs. 1.06%; P = 0.025), deep wound infection (2.67% vs. 2.61%; P = 0.01), sepsis (1.68% vs. 0.79%; P < 0.001), reintubation (1.80% vs. 1.30%) (P = 0.04),and number of packed red blood cell (pRBC) transfused intraoperatively (0.39 ± 1.21 units vs. 0.22 ± 0.79 units; P <0.001). There was no significant difference in rate of graft failure, return to the OR, myocardial infarction, death, or LOS. In regression analysis, those undergoing NA were less likely to require pRBC transfusion intraoperatively (OR: 0.43; 95% CI: 0.31-0.61; P < 0.001), however no other outcomes reached statistical significance.

CONCLUSION

Although younger and less frail, veteran patients undergoing GA for lower extremity revascularization had higher rates of postoperative ileus, pneumonia, deep wound infection, sepsis, and need for transfusion as compared to those undergoing NA. There was no significant difference in the rate of other major complications, myocardial infarction, death or LOS. After adjustment, only intraoperative transfusion remained statistically significant, likely reflecting longer and more complex cases for those that undergo general anesthesia rather than the effect of anesthetic choice itself.

Regional anesthesia for vascular surgery

Patients presenting for vascular surgery present a challenge to anesthesiologists because of their severe systemic comorbidities. Regional anesthesia has been used as a primary anesthetic technique for many vascular procedures to avoid the cardiovascular and pulmonary perturbations associated with general anesthesia. In this article the use of regional anesthesia for carotid endarterectomy, open and endovascular abdominal aortic aneurysm repair, infrainguinal arterial bypass, lower extremity amputation, and arteriovenous fistula formation is described. A focus is placed on reviewing the literature comparing anesthetic techniques, with brief descriptions of the techniques themselves.

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.

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.

Risk-Adapted Outcome After Endovascular Aortic Aneurysm Repair:Analysis of Anesthesia Types Based on EUROSTAR Data

PURPOSE

To compare anesthesia techniques in high-risk versus low-risk patients treated with endovascular aortic aneurysm repair (EVAR) with respect to outcomes.

METHODS

From July 1997 to August 2004, 5557 patients were enrolled in the EUROSTAR registry by 164 centers. Low-risk and high-risk patients were each divided into 3 groups according to anesthesia used during operation [general (GA), regional (RA), and local (LA)], resulting in 6 groups. Differences in preoperative and operative details among the 3 types of anesthesia were analyzed using a chi-square test for discrete variables and the Kruskal-Wallis test for continuous variables for each risk profile. Multivariate logistic regression analysis was performed on early complications.

RESULTS

Intensive care unit (ICU) admission was less frequent for high-LA (1.2% of patients) than high-RA (7.8%, p=0.0071) and high-GA (16.2%, p<0.0001), but high-RA still had a distinct advantage (p<0.0001) over high-GA. Systemic complications were lower both for high-LA (9.0%, p=0.0128) and for high-RA (10.7%, p<0.0001) than for high-GA (18.3%). Early death (< or =30 days) was reduced in high-RA (3.0%) versus high-GA (4.3%, p=0.0286).

CONCLUSION

On the basis of the EUROSTAR data, high-risk patients in particular attain important advantages from minimally invasive anesthetic techniques. Mortality, morbidity, hospital stay, and ICU admission are significantly lower for locoregional versus general anesthesia in the EUROSTAR registry. These results should encourage greater use of regional anesthesia in high-risk patients. Local anesthesia seems to be of similar benefit for EVAR in high-risk patients.

The effects of the type of anesthesia on outcomes of lower extremity infrainguinal bypass

OBJECTIVE

Three main types of anesthesia are used for infrainguinal bypass: general endotracheal anesthesia (GETA), spinal anesthesia (SA), and epidural anesthesia (EA). We analyzed a large clinical database to determine whether the type of anesthesia had any effect on clinical outcomes in lower extremity bypass.

METHODS

This study is an analysis of a prospectively collected database by the National Surgical Quality Improvement Program (NSQIP) of the Veterans Affairs Medical Centers. All patients from 1995 to 2003 in the NSQIP database who underwent infrainguinal arterial bypass were identified via Current Procedural Terminology codes. The 30-day morbidity and mortality outcomes for various types of anesthesia were compared by using univariate analysis and multivariate logistic regression to control for confounders.

RESULTS

The NSQIP database identified 14,788 patients (GETA, 9757 patients; SA, 2848 patients; EA, 2183 patients) who underwent a lower extremity infrainguinal arterial bypass during the study period. Almost all patients (99%) were men, and the mean age was 65.8 years. The type of anesthesia significantly affected graft failure at 30 days. Compared with SA, the odds of graft failure were higher for GETA (odds ratio, 1.43; 95% confidence interval [CI], 1.16-1.77; P = .001). There was no statistically significant difference in 30-day graft failure between EA and SA. Regarding cardiac events, defined as postoperative myocardial infarction or cardiac arrest, patients with normal functional status (activities of daily living independence) and no history of congestive heart failure or stroke did worse with GETA than with SA (odds ratio, 1.8; 95% CI, 1.32-2.48; P < .0001). There was no statistically significant difference between EA and SA in the incidence of cardiac events. GETA, when compared with SA and EA, was associated with more cases of postoperative pneumonia (odds ratio: 2.2 [95% CI, 1.1-4.4; P = .034]. There was no significant difference between EA and SA with regard to postoperative pneumonia. Compared with SA, GETA was associated with an increased odds of returning to the operating room (odds ratio, 1.40; 95% CI, 1.20-1.64; P < .001), as was EA (odds ratio, 1.17; 95% CI, 1.05-1.31; P = .005). GETA was associated with a longer surgical length of stay on univariate analysis, but not after controlling for confounders. There was no significant difference in 30-day mortality among the three groups with univariate or multivariate analyses.

CONCLUSIONS

Although GETA is the most common type of anesthesia used in infrainguinal bypasses, our results suggest that it is not the best strategy, because it is associated with significantly worse morbidity than regional techniques.

Intraoperative myocardial ischemia in peripheral vascular surgery: general anesthesia vs combined sciatic and femoral nerve blocks

STUDY OBJECTIVE

The aim of this study was to compare the frequency of intraoperative myocardial ischemia in lower extremity vascular surgery with general anesthesia vs regional anesthesia via combined sciatic and femoral nerve blocks.

DESIGN

This is a prospective, randomized study.

SETTING

This study was set at an academic medical center.

PATIENTS

The study included 50 patients scheduled for elective lower extremity vascular surgery.

INTERVENTIONS

Patients in group 1 received balanced general anesthesia, whereas patients in group 2 received combined sciatic and femoral nerve blocks with 40 mL of 0.375% bupivacaine. Monitoring included a radial artery catheter and multilead, dual-channel electrocardiogram with computerized ST-segment analysis. Blood pressure and heart rate variations were maintained within 10% of preoperative values by adjusting anesthetic depth, fluid replacement, and vasoactive drug dosages.

MEASUREMENTS AND MAIN RESULTS

An ST-segment depression of at least 1 mm or elevation of at least 2 mm lasting for more than 1 minute was considered a significant episode of myocardial ischemia. Intraoperative hemodynamic data and the frequency of significant ST-segment change episodes were recorded. The number of patients with ischemic episodes and the total number of these episodes were lower in group 2 than in group 1 (1 patient vs 7 patients, P = 0.02; and 2 vs 14 episodes, P = 0.04). No significant difference was found between groups 1 and 2 regarding systolic or diastolic arterial pressures, or heart rate.

CONCLUSION

Compared with general anesthesia, combined sciatic and femoral nerve blocks reduce the frequency of intraoperative myocardial ischemia in patients undergoing lower extremity vascular surgery.

Anesthesia Technique and Outcomes of Endovascular Aneurysm Repair

Anesthetic techniques vary widely in the endovascular repair of abdominal aortic aneurysms (EVAR). Previous studies have demonstrated the feasibility of using local anesthesia. However, the ideal anesthetic technique has not been determined. This study examines whether anesthetic technique influences the outcomes of EVAR. Data regarding demographics, risk factors, procedural characteristics, recovery characteristics, treatment complications, acute (<30 day) medical complications, mortality, and anesthetic type were prospectively collected during the AneuRx phase II aortic endograft trial. Patient cohorts receiving general, regional, or local anesthesia were compared. From 1997 to 1998, 424 patients underwent EVAR at 13 sites using the AneuRx Bifurcated endograft. There were 279 patients in the general anesthesia group, 95 patients in the regional group, and 50 patients in the local group. Risk factors were similar. There were no significant differences in age, gender, American Society of Anesthesiologists grade, length of anesthesia, branch artery occlusions, proximal endoleaks, failed implants, or open surgical conversions. Cardiac, renal, and wound-healing complications were all lower in the local group. Mortality was equivalent among the three groups. (p > 0.05, ANOVA). From these results we concluded that EVAR with local anesthesia is a safe and efficacious method that may reduce recovery times and postoperative medical morbidity compared to use of general or spinal/epidural anesthesia.

Intraoperative management: peripheral vascular surgery

Lower extremity atherosclerotic disease affects nearly 10 million people in the United States. Recent advances in diagnostic imaging and interventional techniques help many patients avoid more invasive surgical procedures. Those reaching the operating room, however,represent a distilled subset of patients who are prone to significant comorbidities. We outline current treatment strategies and discuss anesthetic concerns and techniques for these complex patients.

General anesthesia versus regional anesthesia

No distinct advantage is apparent between regional and general anesthesia when considering perioperative cardiac morbidity and mortality in peripheral vascular surgery. However, there is some evidence to support regional anesthesia over general anesthesia in an effort to optimize graft patency if the regional technique is extended into the postoperative period to provide neuraxial analgesia. An inadequate number of randomized, controlled trials have been conducted to determine whether regional or general anesthesia should be performed for carotid endarterectomy. The nonrandomized trials do support regional anesthesia by virtue of reductions in stroke, myocardial infarction, and death. A randomized, prospective trial is needed to verify these outcomes. The choice of technique does not appear to affect mortality in patients requiring hip fracture surgery, although Urwin et al. (29) reported less 1-month mortality in patients receiving regional anesthesia. General anesthesia has been associated with increased blood loss and thromboembolic complications in patients undergoing hip fracture repair. Epidural anesthesia has been shown to promote quicker return of bowel function postoperatively when the catheter has been sited at T12 or higher. Anastomotic breakdown in patients with epidural anesthesia/analgesia has rarely been reported. Most studies tend to show quicker return of bowel function when local anesthetics alone are administered epidurally.

Epidural analgesia reduces postoperative myocardial infarction: a meta-analysis

Postoperative cardiac morbidity and mortality continue to pose considerable risks to surgical patients. Postoperative epidural analgesia is considered to have beneficial effects on cardiac outcomes. The use in high-risk cardiac patients remains controversial. No study has shown that postoperative epidural analgesia decreases postoperative myocardial infarction (PMI) or death. All studies are underpowered to show such a result, and the cost of conducting a large trial is prohibitive. We performed a metaanalysis to determine whether postoperative epidural analgesia continued for more than 24 h after surgery reduces PMI or in-hospital death. The available databases were searched for randomized controlled trials of epidural analgesia that was extended at least 24 h into the postoperative period. The search yielded 17 studies, of which 11 were randomized controlled trials comprising 1173 patients. Metaanalysis was conducted by using the fixed-effects model, calculating both an odds ratio and a rate difference. Postoperative epidural analgesia resulted in better analgesia for the first 24 h after surgery. The rate of PMI was 6.3%, with lower rates in the Epidural group (rate difference, -3.8%; 95% confidence interval [CI] -7.4%, -0.2%; P = 0.049). The frequency of in-hospital death was 3.3%, with no significant difference between Epidural and Nonepidural groups (rate difference, -1.3%; 95% CI, -3.8%, 1.2%, P = 0.091). Subgroup analysis of postoperative thoracic epidural analgesia showed a significant reduction in PMI in the Epidural group (rate difference, -5.3%; 95% CI, -9.9%, -0.7%; P = 0.04).

IMPLICATIONS

Postoperative epidural analgesia, especially thoracic epidural analgesia, continued for more than 24 h reduces postoperative myocardial infarctions.

Effect of epidural anesthesia and analgesia on perioperative outcome: a randomized, controlled Veterans Affairs cooperative study

OBJECTIVE

To test the hypothesis that epidural anesthesia and postoperative epidural analgesia decrease the incidence of death and major complications during and after four types of intraabdominal surgical procedures.

SUMMARY BACKGROUND DATA

Even though many beneficial aspects of epidural anesthesia have been reported, clinical trials of epidural anesthesia for outcome of surgical patients have shown conflicting results.

METHODS

The authors studied 1,021 patients who required anesthesia for one of the intraabdominal aortic, gastric, biliary, or colon operations. They were assigned randomly to receive either general anesthesia and postoperative analgesia with parenteral opioids (group 1) or epidural plus light general anesthesia and postoperative epidural morphine (group 2). The patients were monitored for death and major complications during and for 30 days after surgery, as well as for postoperative pain, time of ambulation, and length of hospital stay.

RESULTS

Overall, there was no significant difference in the incidence of death and major complications between the two groups. For abdominal aortic surgical patients, unlike the other three types of surgical patients, the overall incidence of death and major complications was significantly lower in group 2 patients (22%) than in group 1 patients (37%), stemming from differences in the incidence of new myocardial infarction, stroke, and respiratory failure between the two groups. Overall, group 2 patients received significantly less analgesic medication but had better pain relief than group 1 patients. In group 2 aortic patients, endotracheal intubation time was 13 hours shorter and surgical intensive care stay was 3.5 hours shorter.

CONCLUSIONS

The effect of anesthetic and postoperative analgesic techniques on perioperative outcome varies with the type of operation performed. Overall, epidural analgesia provides better postoperative pain relief. Epidural anesthesia and epidural analgesia improve the overall outcome and shorten the intubation time and intensive care stay in patients undergoing abdominal aortic operations.

Epidural analgesia and arterial reconstructive surgery to the leg: effects on fibrinolysis and platelet degranulation

It has been suggested that the incidence of early graft occlusion after arterial reconstructive surgery to the leg may be decreased by epidural analgesia. This effect may be mediated by the suppression of the usual cortisol response to surgery, which results in increased circulating plasminogen activator inhibitor-1 with consequent adverse effects on fibrinolysis. To investigate this and other potential mechanisms, 30 patients undergoing arterial reconstructive surgery to the leg were randomized to receive either general anaesthesia or general anaesthesia plus epidural analgesia. Post-operative analgesia was provided by morphine infusion or epidural analgesia, respectively. Blood samples were collected at 0, 2, 4, 6, 12 and 24 h, and 2, 3 and 5 days and analysed for cortisol, plasminogen activator inhibitor-1 antigen, interleukin-6 and beta thromboglobulin. The incidence of graft-related and systemic complications was recorded for 30 days. Only one patient developed early graft occlusion that required embolectomy and eventually amputation. There were no significant changes from control values in either group of patients in circulating cortisol, plasminogen activator inhibitor-1 and beta thrombogobulin (a marker for platelet degranulation). Interleukin-6 values increased significantly in both groups after 4 h and remained elevated until day 3. There were no significant differences between the groups in any variable measured. We conclude that any effect of epidural analgesia on early graft patency is unlikely to be mediated by fibrinolysis or platetlet degranulation.

[Locoregional neuraxial anesthesia and vascular surgery: the benefits]

PURPOSE

To assess the advantages of neuraxial blockade (NB) during and after vascular surgery and to confront them with the risk of epidural or spinal hematoma.

MAIN FINDINGS

NB may reduce the risk of thrombotic occlusion following lower extremity vascular reconstruction. This effect of NB may be attributed to reduced hypercoagulability, decreased peripheral resistance and increased graft flow. In patients under general anesthesia, only those authors using an aggressive perioperative management (pulmonary artery catheter monitoring, intensive care unit admission) were able to report grafts patency rates similar to those obtained with NB. NB facilitates the modulation of the hemodynamic and hormonal stress responses during the perioperative period. It also produces superior postoperative analgesia. Still, the impact of NB on cardiac morbidity following aortic reconstructive surgery remains open to debate. Only very few cases of epidural hematomas associated to NB following vascular surgery have been reported. They implicated patients who received either fibrinolytic medication, continuous heparin infusion, or both. Low molecular weight heparins may increase the risk or epidural hematoma and, should their administration become more frequent during vascular surgery, the safety of NB would then have to be reassessed.

CONCLUSION

NB during vascular surgery is a safe and well-established practice. It offers many theoretical and demonstrated advantages. NB is particularly beneficial and economical for lower extremity vascular reconstruction. Still, NB may not be the best approach if the administration of fibrinolityc medication or prolonged heparin infusion is contemplated.

Transurethral resection of the prostate

Transuretheral resection of prostate (TURP) is a common operation in most hospitals. The patients are elderly and usually have concomitant diseases such as diabetes, hypertension, cardiac and respiratory ailments that increase their perioperative risk. Perioperative morbidity and mortality approaches 20% and 1% respectively. Regional anesthesia, notably spinal anesthesia, offers many advantages over general anesthesia for TURP with some evidence of lower morbidity even though similar mortality rates and overall outcomes are reported for both groups. Procedure-specific complications include TURP syndrome, bladder perforation, primary fibrinolysis, bacteremia, and septicemia. All are associated with significant morbidity and mortality but amenable to early and aggressive therapeutic intervention.

Feasibility of endovascular repair of abdominal aortic aneurysms with local anesthesia with intravenous sedation

PURPOSE

Local anesthesia has been shown to reduce cardiopulmonary mortality and morbidity rates in patients who undergo selected peripheral vascular procedures. The efforts to treat abdominal aortic aneurysms (AAAs) with endovascular techniques have largely been driven by the desire to reduce the mortality and morbidity rates as compared with those associated with open aneurysm repair. Early results have indicated a modest degree of success in this goal. The purpose of this study was to investigate the feasibility of endovascular repair of AAAs with local anesthesia.

METHODS

During a 14-month period, 47 patients underwent endovascular repair of infrarenal AAAs with local anesthesia that was supplemented with intravenous sedation. Anesthetic monitoring was selective on the basis of comorbidities. The patient ages ranged from 48 to 93 years (average age, 74.4 +/- 9.8 years). Of the 47 patients, 55% had significant coronary artery disease, 30% had significant chronic obstructive pulmonary disease, and 13% had diabetes. The average anesthesia grade was 3.1, with 30% of the patients having an average anesthesia grade of 4. The mean aortic aneurysm diameter was 5.77 cm (range, 4.5 to 12.0 cm). All the implanted grafts were bifurcated in design.

RESULTS

Endovascular repair of the infrarenal AAA was successful for all 47 patients. One patient required the conversion to general anesthesia to facilitate the repair of an injured external iliac artery via a retroperitoneal approach. The operative mortality rate was 0. No patient had a myocardial infarction or had other cardiopulmonary complications develop in the perioperative period. The average operative time was 170 minutes, and the average blood loss was 623 mL (range, 100 to 2500 mL). The fluid requirements averaged 2491 mL. Of the 47 patients, 46 (98%) tolerated oral intake and were ambulatory within 24 hours of graft implantation. The patients were discharged from the hospital an average of 2.13 days after the procedure, with 87% of the patients discharged less than 48 hours after the graft implantation. Furthermore, at least 30% of the patients could have been discharged on the first postoperative day except for study protocol requirements for computed tomographic scanning at 48 hours.

CONCLUSION

This is the first reported series that describes the use of local anesthesia for the endovascular repair of infrarenal AAAs. Our preliminary results indicate that the endovascular treatment of AAAs with local anesthesia is feasible and can be performed safely in a patient population with significant comorbidities. The significant potential advantages include decreased cardiopulmonary morbidity rates, shorter hospital stays, and lower hospital costs. A definitive evaluation of the benefits of local anesthesia will necessitate a direct comparison with other anesthetic techniques.

Epidural versus general anesthesia: does anesthetic management influence early infrainguinal graft thrombosis?

A few contemporary reports have suggested that the use of epidural anesthesia may favorably influence early graft patency in patients undergoing infrainguinal revascularization. In order to test this hypothesis, we have retrospectively reviewed our experience with 303 primary femoropopliteal-tibial bypass procedures in 294 patients from January 1989 through June 1994. A total of 145 of these operations were done under epidural anesthesia (EA) and 158 under general anesthesia (GA); the demographic profiles for the patients in both of these groups were nearly identical. Thirteen patients (4.2%) died during the perioperative period (EA 3.4%, GA 5.0%; p = 0.48). Early graft thrombosis occurred in 35 patients (12%) during the same hospital admission (EA 14%, GA 9.4%; p = 0.28). There were no significant differences in the graft thrombosis rates for EA and GA with respect to surgical indications (claudication versus limb salvage), graft materials (vein versus synthetic), or the extent of revascularization (popliteal versus crural). Most graft failures appeared to be related to such conventional factors as disadvantaged outflow vessels and/or specific technical complications. Therefore, we conclude that the choice between EA and GA should continue to be made selectively on the basis of traditional anesthetic considerations.

Local anesthesia for infrainguinal arterial reconstruction

PURPOSE

Perioperative cardiac complications occur in 4% to 6% of patients undergoing infrainguinal revascularization under general, spinal, or epidural anesthesia. The risk may be even greater in patients whose cardiac disease cannot be fully evaluated or treated before urgent limb salvage operations. Prompted by these considerations, we investigated the feasibility and results of using local anesthesia in these high-risk patients.

METHODS

From January 1, 1994, through August 30, 1996, 86 infrainguinal reconstructions were performed under local infiltration anesthesia (0.5% or 1.0% lidocaine). Supplementary intravenous sedation with propofol or other agents was given as needed for patients comfort. Most patients had arterial lines but Swan Ganz catheters were used infrequently. Postoperatively, continuous electrocardiographic monitoring was continued in the intermediate or intensive care units. Patients ranged in age from 37 to 86 years (mean 68 +/- 12); 47% were diabetic, 69% had severe coronary artery disease, and 14% had end-stage renal disease.

RESULTS

Operations included 7 femoral-femoral, 21 femoral-popliteal, 16 femoral-tibial and 13 popliteal-tibial bypass grafts, 9 pseudoaneurysms, and 20 distal graft revisions (+/- thrombectomy). Autogenous vein was used in eight of the femoral-popliteal and all of the femoral-tibial and popliteal-tibial bypass grafts. There were two postoperative deaths. One patient died of a stroke (1.2%) on postoperative day (POD) 2 and one died on POD 27 of unknown cause. Two other (2%) patients had nonfatal subendocardial myocardial infarctions. Conversion to general anesthesia was required in four (5%) operations, three because patients became agitated and one because a long segment of vein had to be harvested from the opposite leg. Otherwise, patients tolerated the procedures well and postanesthetic recovery problems were minimized.

CONCLUSIONS

Limb salvage operations can be done under local anesthesia with acceptable complication rates. In selected patients with high-risk coronary artery disease, local anesthesia has theoretic and practical advantages and should be considered an alternative to general or regional anesthesia.

Selective use of the intensive care unit after nonaortic arterial surgery

PURPOSE

The purpose of this study was to determine whether the institution of a clinical protocol combining 6 hours of recovery room observation and guidelines for intensive care unit (ICU) admission would allow selected patients to be safely transferred directly to a surgical floor after nonaortic arterial reconstruction.

METHODS

After a clinical pathway was formed, 134 consecutive patients undergoing 154 nonaortic arterial operations were prospectively enrolled in this study. Patients requiring ICU care and the responsible factors were identified. Comparisons of risk factors and demographics were made between those patients who did and did not require ICU care.

RESULTS

Twelve (7.8%) patients spent a total of 27 days in the ICU (range 1 to 11 days). As per our guidelines four patients were transferred to the ICU for invasive monitoring, and four were sent to the ICU because of refractory hemodynamic instability or arrhythmia in the postanesthetic recovery room. An additional four patients were transferred to the ICU after having been on the surgical floor for 24 to 72 hours because of the following perioperative complications: prolonged chest pain (one), pneumonia (one), heart failure (one), and graft occlusion requiring a urokinase infusion. Patients admitted to the ICU were more likely to have heart disease (p = 0.02) and to have had an operation other than carotid endarterectomy (p = 0.04) than those who were not. The 30-day mortality rate was 1.4%.

CONCLUSIONS

The implementation of a clinical protocol similar to the one used in this study will allow many patients undergoing nonaortic vascular surgery to avoid the use of the ICU. This approach will conserve hospital and financial resources without adversely affecting patient morbidity and mortality rates.

Incidence and hospital stay for cardiac and pulmonary complications after abdominal surgery

OBJECTIVE

Internists frequently evaluate preoperative cardiopulmonary risk and co-manage cardiac and pulmonary complications, but the comparative incidence and clinical importance of these complications are not clearly delineated. This study evaluated incidence and length of stay for both cardiac and pulmonary complications after elective laparotomy.

DESIGN

Nested case-control.

SETTING

University-affiliated Department of Veterans Affairs Hospital.

PATIENTS

Computerized registry of all 2,291 patients undergoing elective abdominal operations from 1982 to 1991.

MEASUREMENT AND MAIN RESULTS

Strategy for ascertainment and verification of complications was systematic and explicit. The charts of all 116 patients identified by the registry as having complications and 412 (19%) randomly selected from 2,175 remaining patients were reviewed to verify presence or absence of cardiac or pulmonary complications, using explicit criteria and independent abstraction of pre- and postoperative components of charts. From these 528 validated cases and controls (23% of the cohort), 96 cases and 96 controls were matched by operation type and age within ten years. Hospital and intensive care unit stays were significantly longer (p < 0.0001) for the cases than for the controls (24.1 vs 10.3 and 5.6 vs 1.5 days, respectively). All 19 deaths occurred among the cases. Among the cases, pulmonary complications occurred significantly more often than cardiac complications (p < 0.00001) and were associated with significantly longer hospital stays (22.7 vs 10.4 days, p = 0.001). Combined cardiopulmonary complications occurred among 28% of the cases. Misclassification-corrected incidence rates for the entire cohort were 9.6% (95% CI 7.2-12.0) for pulmonary and 5.7% (95% CI 3.6-7.7) for cardiac complications.

CONCLUSIONS

For noncardiac surgery, previous research has focused on cardiac risk. In this study, pulmonary complications were more frequent, were associated with longer hospital stay, and occurred in combination with cardiac complications in a substantial proportion of cases. These results suggest that further research is needed to fully characterize the clinical epidemiology of postoperative cardiac and pulmonary complications and better guide preoperative risk assessment.