Thoracic epidural anesthesia for off-pump coronary artery bypass without intubation

Comparing Conscious Sedation With Regional Anesthesia Versus General Anesthesia in Minimally Invasive Mitral Valve Surgery With Right-Sided Minithoracotomy: A Retrospective Study

OBJECTIVES

The aims of the present study were to evaluate and compare the safety and feasibility, including hospitalization, intensive care unit (ICU) stay, frequency of conversion to general anesthesia (GA), pH, PaCO₂, and PaO₂, of selected patients who underwent minimally invasive mitral valve surgery (MIMVS) via a right minithoracotomy under conscious sedation (CS) to avoid GA. The authors also aimed to evaluate the perioperative management of spontaneous breathing.

DESIGN

A retrospective, observational study.

SETTING

Single-center.

PARTICIPANTS

This study enrolled 101 patients who underwent MIMVS under CS or GA.

INTERVENTIONS

The patients who underwent MIMVS were managed under CS or GA according to indication criteria.

MEASUREMENTS AND MAIN RESULTS

ICU stay (p = 0.010), postoperative time until first fluid intake (p < 0.0001), and duration of mechanical ventilation (p = 0.004) were shorter in the CS group than in the GA group. No patients converted to GA from CS. PaCO₂ during cardiopulmonary bypass (CPB) in the CS group was significantly lower than that in the GA group. However, PaCO₂ at the termination of CPB in the CS group was significantly higher than that in the GA group.

CONCLUSIONS

In the CS group, advanced-age patients with comorbidities underwent mitral surgery without postoperative complications. The authors' findings suggested that MIMVS under CS could be a potentially less-invasive method, providing a quicker recovery than MIMVS under GA.

Regional Anesthesia in Cardiac Surgery: A Friend or A Foe?

Escalating costs and change in the profile of patients presenting for cardiac surgery requires modification of perioperative management strategies. Regional anesthesia has played an integral part of many fast-track anesthesia protocols across North America and Europe. This review suggests that for patients undergoing coronary artery bypass graft surgery, the risk-to-benefit ratio is in favor of epidural and spinal anesthesia, provided there are no specific contraindications and the guidelines for the use of regional techniques in cardiac surgery are followed. Patients managed with regional techniques seem to benefit from superior postoperative analgesia, shorter postoperative ventilation, reduced incidence of supraventricular arrhythmia, and lower rates of perioperative myocardial infarction. The results of this analysis suggest that for each episode of neurologic complication, 20 myocardial infarctions and 76 episodes of atrial fibrillation would be prevented, thus, we would consider the regional anesthesia and analgesia to be an effective strategy that improves perioperative morbidity. However, other treatment modalities such as the addition of calcium channel blockers, aspirin, and beating heart surgery, are also suggested to be beneficial in cardiac surgical patients and may impose less risk than the use of regional techniques. We believe that the results presented in this review are encouraging enough to permit continued investigation. A prospective, randomized, controlled multicenter trial needs to be adequately powered to answer important clinical questions and allow for a long-term follow-up.

Activation of Coagulation and Fibrinolysis after Off-Pump Coronary Artery Bypass Grafting with or without Endotracheal General Anesthesia

Objective

In this study, we measured the activity of coagulation and fibrinolysis and clarified the presence of certain differences between off-pump coronary artery bypass grafting (OPCAB) cases and awake off-pump coronary artery bypass grafting (AOCAB) cases to evaluate whether AOCAB is actually safe from the viewpoint of coagulability.

Methods

8 underwent OPCAB and 6 underwent AOCAB. The following factors inducing coagulation and fibrinolysis were measured for upto 5 days after the operation: platelet counts, prothrombin time, activated partial thromboplastin time, fibrinogen, fibrin degeneration products, D-dimer, thrombin-antithrombin III complex (TAT), α2-plasmin inhibitor-plasmin complex, prothrombin fragment 1, 2 (F1+2), thrombomodulin, β-thromboglobulin (β-TG), and platelet factor-4.

Results

At 5 days after the operation, fibrin degeneration products, D-dimer, α2–plasmin inhibitor-plasmin complex, and F1 + 2 levels of the OPCAB group were significantly higher compared with their baseline values and those of the AOCAB group. At 5 days after the operation, thrombin-antithrombin III complex levels of the OPCAB group were significantly higher than those of the AOCAB group. Fibrinogen levels of the OPCAB group were significantly higher than their baseline values at 3 days after the operation (POD3) and 5 days after the operation (POD5).

Conclusions

In this study, the hypercoagulable state at POD5 was suggested in the patients in the OPCAB group, but not in those in the AOCAB group. Further study is necessary to confirm these results, and future studies would evaluate the potential benefit of AOCAB procedure from the viewpoint of perioperative coagulability.

Regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy: American Society of Regional Anesthesia and Pain Medicine Evidence-Based Guidelines (Third Edition)

The actual incidence of neurologic dysfunction resulting from hemorrhagic complications associated with neuraxial blockade is unknown. Although the incidence cited in the literature is estimated to be less than 1 in 150,000 epidural and less than 1 in 220,000 spinal anesthetics, recent epidemiologic surveys suggest that the frequency is increasing and may be as high as 1 in 3000 in some patient populations.Overall, the risk of clinically significant bleeding increase with age,associated abnormalities of the spinal cord or vertebral column, the presence of an underlying coagulopathy, difficulty during needle placement,and an indwelling neuraxial catheter during sustained anticoagulation( particularly with standard heparin or low-molecular weight heparin). The need for prompt diagnosis and intervention to optimize neurologic outcome is also consistently reported. In response to these patient safety issues, the American Society of Regional Anesthesia and Pain Medicine (ASRA) convened its Third Consensus Conference on Regional Anesthesia and Anticoagulation. Practice guidelines or recommendations summarize evidence-based reviews. However, the rarity of spinal hematoma defies a prospective randomized study, and there is no current laboratory model. As a result,the ASRA consensus statements represent the collective experience of recognized experts in the field of neuraxial anesthesia and anticoagulation. These are based on case reports, clinical series, pharmacology,hematology, and risk factors for surgical bleeding. An understanding of the complexity of this issue is essential to patient management.

[Coronary artery bypass grafting in conscious patients: a procedure with a perspective?]

Patients undergoing coronary artery bypass grafting increasingly show severe co-morbidities, which can negatively affect the outcome. Recent developments in cardiac surgery have therefore focused on minimizing the invasiveness of the procedure by revascularization on the beating heart without cardiopulmonary bypass, and by reducing surgical trauma using smaller surgical incisions. Progress in minimally invasive cardiac surgery has led to minimally invasive anesthesia, i.e. using high thoracic epidural anesthesia as the sole technique in the conscious patient (awake coronary artery bypass grafting, ACAB). Published data on ACAB procedures in smaller cohorts have demonstrated that the procedure is safe. Significant complications occurred in 7.1% of patients. A particular cause of concern during ACAB surgery is the development of spinal epidural hematoma the risk of which has been estimated to be as high as 1:1,000. A thorough risk-benefit analysis has therefore to be made. Currently, ACAB surgery remains limited to few specialized centers and highly selected patients.

Intrathecal and Epidural Anesthesia and Analgesia for Cardiac Surgery

Adequate postoperative analgesia prevents unnecessary patient discomfort. It may also decrease morbidity, postoperative hospital length of stay and, thus, cost. Achieving optimal pain relief after cardiac surgery is often difficult. Many techniques are available, and all have specific advantages and disadvantages. Intrathecal and epidural techniques clearly produce reliable analgesia in patients undergoing cardiac surgery. Additional potential benefits include stress response attenuation and thoracic cardiac sympathectomy. The quality of analgesia obtained with thoracic epidural anesthetic techniques is sufficient to allow cardiac surgery to be performed in awake patients without general endotracheal anesthesia. However, applying regional anesthetic techniques to patients undergoing cardiac surgery is not without risk. Side effects of local anesthetics (hypotension) and opioids (pruritus, nausea/vomiting, urinary retention, and respiratory depression), when used in this manner, may complicate perioperative management. Increased risk of hematoma formation in this scenario has generated much of lively debate regarding the acceptable risk-benefit ratio of applying regional anesthetic techniques to patients undergoing cardiac surgery.

Composite Bilateral Internal Thoracic Artery Grafts via Standard Sternotomy for Lateral Wall Revascularization in Conscious Patients

BACKGROUND

A new technique has been developed that permits complete arterial revascularization of the lateral wall of the heart using in situ bilateral internal thoracic artery grafts in awake patients. This technique, performed without cardiopulmonary bypass or mechanical ventilation, creates the least invasive revascularization method for the lateral wall of the heart yet described.

METHODS

In 4 patients, double or triple vessel coronary artery bypass grafting was performed without general anesthesia. A high thoracic epidural anesthesia was started 1 hour before surgery. Bilateral internal thoracic arteries were harvested and all anastomoses were performed with the off-pump technique via standard median sternotomy. Circumflex branches were anastomosed with the left internal thoracic artery via a heart positioner.

RESULTS

All patients remained awake throughout the whole procedure. There was no perioperative myocardial infarction or mortality. Pneumothorax was observed in only 1 patient and did not hinder the procedure. There were no hemodynamic changes during lateral wall revascularization. Two patients required unexpected coronary endarterectomy during circumflex and right coronary artery anastomoses.

CONCLUSIONS

Complete arterial revascularization via median sternotomy using in situ bilateral internal thoracic artery grafts without general anesthesia is a feasible and safe procedure for multivessel disease. This approach allows for complete coronary artery revascularization in patients with contraindications for general anesthesia with or without cardiopulmonary bypass.

Reversed-J inferior versus full median sternotomy: which is better for awake coronary bypass surgery

BACKGROUND

The aim of this study was to ascertain whether the approach with a less invasive reversed-J inferior sternotomy could improve intraoperative patient compliance and postoperative recovery than the standard median sternotomy.

METHODS

Seventeen patients underwent elective single coronary artery bypass graft operation under high thoracic epidural anesthesia without endotracheal intubation. The reversed-J sternotomy was performed in 10 patients (Group A) and full sternotomy in 7 patients (Group B). The technical and surgical difficulties, pulmonary functions (by spirometric tests) and hospital stay were assessed.

RESULTS

Through the reversed-J sternotomy coronary revascularization was accomplished without any additional technical difficulties and with a good exposure of both the left anterior descending artery and the left internal thoracic artery. No conversion to standard sternotomy and no intubation were observed. Additional doses of local anesthetic at jugular notch was not required in Group A. Pleura was opened more in Group B (57% vs. 20%; p = 0.14). Oxygen saturation was better in Group A during the surgical procedure (98.8 +/- 0.7% vs. 97.1 +/- 2.1%; p = 0.033), however, intraoperative PaCO2 was similar in both the groups. The patients in Group A were discharged from the hospital earlier (3.2 +/- 1.5 vs. 7.3 +/- 3.5 days; p = 0.004).

CONCLUSIONS

Less invasive approach to coronary artery bypass graft operations is possible through combination of the high thoracic epidural anesthesia and a reversed-J sternotomy. This technique is less traumatic for patient and provides practical better oxygenation and shorter hospital stay.

Minimal access coronary revascularisation without cardiopulmonary bypass—the impact of robotic technology in the current clinical practice

Recent advances in interventional cardiology and cardiac surgery have changed the traditional therapeutic algorithms by altering indications, timing and patterns of referral for subsequent surgical treatment. The traditional longitudinal sternomy incision has been the surgical approach of choice for multi-vessel coronary revascularisation. Drawbacks of this incision include potential postoperative morbidity, which translates to a prolonged postoperative length of stay. The combination of minimally invasive direct coronary artery bypass (MIDCAB) with percutaneous transluminal coronary angioplasty (PTCA) or stenting (a hybrid approach) is an alternative therapeutic method for patients with multivessel coronary artery disease. Recent advances in percutaneous interventions have attempted to address the problem of re-stenosis, initially through the deployment of bare metal intra-coronary stents and, more recently, with drug-eluting stents. Developments in coronary revascularisation have focused on reducing both surgical invasiveness and trauma. Patients with significant co-morbid pathologies, the ones undergoing re-interventions, and especially the elderly may benefit from such hybrid procedures by avoiding cardiopulmonary bypass and midline sternotomy. Minimally invasive techniques have revolutionized cardiothoracic surgery by increasing patient satisfaction and by reducing surgical trauma, hospital stay and consequently overall costs. There are however limitations. Robot assisted surgery endeavours to minimise these technical hindrances and so allow better and more accurate surgical practice whilst minimising surgical trauma.

Off-Pump Awake Coronary Revascularization Using Bilateral Internal Thoracic Arteries

BACKGROUND

A new technique has been developed that permits complete arterial revascularization of the lateral and/or inferior wall of the heart using in situ bilateral internal thoracic artery grafts in awake patients. This technique, without cardiopulmonary bypass and mechanical ventilation, creates the least invasive revascularization method for the lateral and/or posterior wall of the heart yet described.

METHODS

In 7 patients double or triple vessel coronary artery bypass grafting was performed without general anesthesia. A high thoracic epidural anesthesia was started one hour before surgery. Bilateral internal thoracic arteries were harvested and all anastomoses were performed with the off-pump technique by standard median sternotomy. Circumflex, or the right coronary artery, were anastomosed with bilateral internal thoracic arteries using a heart positioner. Six patients received double bypass grafting and one patient received triple bypass grafts (bilateral internal thoracic arteries and one radial artery).

RESULTS

All patients remained awake throughout the whole procedure. There was no perioperative myocardial infarction or mortality. Pneumothorax was observed in three patients, but it was repaired in two. Only one patient completed the procedure with unilateral pneumothorax. There were no hemodynamic and pulmonary problems during lateral or posterior wall revascularization. Two patients required unexpected coronary endarterectomy during circumflex and right coronary artery anastomoses.

CONCLUSIONS

Complete arterial revascularization by median sternotomy using in situ bilateral internal thoracic artery grafts without general anesthesia is a feasible and safe procedure for multivessel disease. This approach gives a chance for awake revascularization of the right and/or circumflex coronary artery.

High thoracic epidural anesthesia for off-pump coronary artery bypass surgery

OBJECTIVE

To assess the feasibility of high thoracic epidural anesthesia combined with sevoflurane for off-pump coronary artery bypass surgery and to evaluate the postoperative pain control, side effects, and perioperative hemodynamics.

DESIGN

Retrospective review of prospectively collected data.

SETTING

A university teaching hospital.

PARTICIPANTS

One hundred six consecutive patients receiving thoracic epidural combined with sevoflurane.

INTERVENTION

From November 1999, the patients undergoing off-pump coronary artery bypass grafting were offered the epidural-inhalation anesthetic approach.

MEASUREMENTS AND MAIN RESULTS

Insertion of the epidural catheter was successful in all but 2 patients; 1 bloody tap occurred and the dura was never punctured, although 1 patient presented with postoperative paraplegia. An emergency spinal cord nuclear magnetic resonance excluded signs of medullary compression caused by epidural or spinal hematoma. Visual analog scale scores for pain during the first 24-hour period were < 2 in all patients. Mean time to extubation was 4.6 +/- 2.9 hours. The average intensive care unit stay was 1.5 +/- 0.8 days. Incidences of perioperative myocardial infarction, myocardial ischemia, and atrial fibrillation were 2.8%, 7.5%, and 10.6%, respectively. Two patients died: 1 from multiorgan failure and the other from myocardial infarction. Heart rate, mean arterial pressure, cardiac index, and systemic vascular resistance were not affected by thoracic epidural alone. Mean arterial pressure and cardiac index decreased (p < 0.05) when general anesthesia was induced and remained stable thereafter. Neither heart rate nor systemic vascular resistance changed from baseline during operation.

CONCLUSIONS

Thoracic epidural as an adjunct to general anesthesia is a feasible technique in off-pump coronary artery bypass surgery. It induces intense postoperative analgesia and does not compromise central hemodynamics.

Off-pump versus on-pump coronary surgery: final results from a prospective randomized study PRAGUE-4

BACKGROUND

Off-pump coronary artery bypass surgery is becoming increasingly popular despite the lack of sufficient evidence from randomized trials. The aim of our prospective, randomized, single-center study was to examine the role of off-pump revascularization among nonselected patients.

METHODS

A total of 400 consecutive nonselected patients (mean age 63 years) scheduled for isolated coronary revascularization were randomized by a cardiologist into two groups: A (on-pump) and B (off-pump). The cardiac surgeon was allowed to change the operative technique at any time after randomization. The only exclusion criterion was an emergency procedure. The primary end point was any of the following within 30 days: death, myocardial infarction, stroke, or new renal failure requiring hemodialysis. The study was analyzed on the intention-to-treat principle.

RESULTS

The primary end point occurred in 4.9% of patients in group A versus 2.9% in group B (not significant). Mortality was 1.1% in group A versus 2.0% in group B (not significant). Preoperative crossover occurred in 5.4% of patients in each group (not significant). Intraoperative conversion was necessary in 9.8% of patients in group B versus 1.1% of patients in group A (p < 0.001). Group B patients had fewer distal anastomoses (2.3 versus 2.7 in group A; p < 0.001), less blood loss (560 versus 680 mL; p < 0.001), lower postoperative creatine kinase MB levels (0.15 versus 0.56 microkat/L; p < 0.001) and lower total hospital costs (3,451 versus 4,387; p < 0.001).

CONCLUSIONS

In our study off-pump technique was applicable in 85% of nonselected patients and is at least as clinically safe and effective as on-pump surgery.

Operative techniques in awake coronary artery bypass grafting

BACKGROUND

Off-pump coronary artery bypass grafting was implemented to reduce trauma of surgical coronary revascularization by avoiding extracorporeal circulation. High thoracic epidural anesthesia further reduces intraoperative stress and postoperative pain. In addition, this technique even allows awake coronary artery bypass grafting, avoiding the drawbacks of mechanical ventilation and general anesthesia in high-risk patients.

METHODS

Thirty-four patients underwent awake coronary artery bypass grafting with left internal thoracic artery to left anterior descending coronary artery by partial lower ministernotomy (n = 20), H-graft technique (n = 2), or rib cage-lifting technique (n = 2). In 9 cases we performed double bypass grafting, and in 1 case we performed triple-vessel coronary artery revascularization through complete median sternotomy. In addition to clinical outcomes, visual analog scale pain scores were recorded on days 1, 2, and 3 after surgery.

RESULTS

Thirty-one patients remained awake throughout the whole procedure. Three patients required secondary intubation because of incomplete analgesia (n = 1) or pneumothorax (n = 2). Procedure time was 90 +/- 31 minutes, and recovery room stay was 4.2 +/- 0.6 hours. There were no in-hospital deaths or serious postoperative complications. In 1 case a graft occlusion was documented on predischarge angiography. Early postoperative pain was low (visual analog scale score of 30 +/- 6).

CONCLUSION

These data demonstrate the feasibility and safety of various surgical coronary revascularization techniques without general anesthesia. Continuation of thoracic epidural analgesia provides good pain control and fast mobilization postoperatively. Surprisingly, the awake coronary artery bypass grafting procedure was well accepted by the patients.

Coronary artery bypass grafting in the awake patient: three years' experience in 137 patients

OBJECTIVE

Our experience with 137 patients operated on without general anesthesia is reviewed to explore the validity of our surgical strategy.

METHODS

Between October 1998 and January 2002, 137 patients underwent coronary artery bypass grafting with high thoracic epidural anesthesia. There were 47 female and 90 male patients, ranging in age from 37 to 92 years (mean, 68 +/- 12 years). Two patients underwent reoperation. Nineteen patients had contraindications for general anesthesia. Target vessels involved were the left anterior descending artery in 122, the right coronary artery in 6, the left anterior descending artery plus right coronary artery in 7, and the left anterior descending artery plus circumflex artery in 2 patients. Coronary artery bypass was performed through limited access in 74 patients (H-graft in 42 and rib cage lifting in 32 patients) and through a median sternotomy in 63 patients. Cardiopulmonary bypass was not used.

RESULTS

In 39 (28.4%) patients pneumothorax was observed during surgical intervention. There was no mortality. Of the 137 patients, 132 (96.3%) completed the procedure awake. In 58 patients the intensive care unit was not used. Eight patients were discharged from the hospital on the day of their operation. Mean length of hospitalization was 1 day (range, 0-3 days). One hundred thirty-one patients were followed up for a period of 3 months and 3 years after their operations, and 94.7% of the patients were symptom free. Control angiograms were obtained in 41 patients. Graft patency was 100%, with one radial artery graft spasm.

CONCLUSIONS

Our initial experience confirms the feasibility and safety of performing coronary artery bypass grafting in the conscious patient without general anesthesia. Further study is required to define the possible extent and limitations of this strategy.

Anaesthetic considerations in patients with chronic pulmonary disease

PURPOSE OF REVIEW

Chronic pulmonary diseases are getting more important in daily anaesthetic practice, because prevalence is increasing and improved anaesthetic techniques have led to the abandonment of previous contraindications to anaesthesia. It is therefore essential for the anaesthetist to be up to date with current clinical concepts and their impact on the conduction of anaesthesia as well as new insights into how to anaesthetise these patients safely.

RECENT FINDINGS

If patients are treated adequately, open and minimally invasive operations can be safely performed under regional and general anaesthesia. The management of acute exacerbations remains challenging, and first-line medical treatment should be supported by non-invasive ventilation. In controlled mechanical ventilation, parameters should be set to avoid dynamic hyperinflation.

SUMMARY

Assessing the functional status of patients admitted for surgery remains a difficult task, and in patients identified as being at risk by clinical examination additional spirometry and blood gas measurements may be helpful. If there are flow limitations and signs of respiratory failure, the anaesthetist should be highly alarmed and monitor the patient closely and invasively, yet there is no reason to deny any patient a substantially beneficial operation.

High thoracic epidural anesthesia as the sole anesthetic for performing multiple grafts in off-pump coronary artery bypass surgery

OBJECTIVES

The feasibility of the use of high thoracic epidural anesthesia as a sole anesthetic in patients undergoing beating heart coronary revascularization avoiding general anesthesia was studied.

DESIGN

A prospective study.

SETTING

A tertiary care medical center.

INTERVENTIONS

Fifteen patients underwent beating heart coronary artery revascularization without endotracheal general anesthesia, between October 2001 to May 2002, using high thoracic epidural anesthesia and analgesia. All the patients underwent epidural catheterization on the evening before the surgery.

MEASUREMENTS AND MAIN RESULTS

The patients received 36 grafts (single, n = 5; double, n = 3; triple, n = 3; quadruple, n = 4). There were 3 female patients and 12 male patients with mean age of 60.6 +/- 5.9 years. Two patients underwent repeat coronary artery bypass. All the patients underwent off-pump coronary artery bypass graft surgery; 2 patients underwent grafting via left thoracotomy and the rest through a midsternotomy. There was no conversion to general anesthesia or cardiopulmonary bypass, and there was no mortality. Mean length of stay in the intensive care unit was 18.2 +/- 4.2 hours and in the hospital was 3.2 +/- 1.2 days.

CONCLUSION

Experience confirms the feasibility of performing multiple coronary artery bypasses in conscious patients without endotracheal general anesthesia.

Routine immediate extubation for off-pump coronary artery bypass grafting without thoracic epidural analgesia

BACKGROUND

The expansion of coronary surgery on the beating heart without cardiopulmonary bypass has led to increasing interest in ultra-fast track anesthesia, allowing extubation of the patient in the operating theater. The techniques described to date combined general anesthesia with thoracic epidural analgesia. We report the routine application of a technique that allows immediate extubation in the majority of patients undergoing off-pump coronary artery bypass grafting without thoracic epidural analgesia.

METHODS

Fast-track anesthesia using an ultra-shortacting opiate remifentanil, without epidural catheter insertion, was used in 160 unselected patients undergoing off-pump coronary artery bypass grafting (aged 43 to 83 years, mean 65 years). There were an average of 2.2 bypass procedures per patient, with the left internal mammary artery used in 93%. Contraindications to immediate extubation were (except for failure to meet standard extubation criteria) hemodynamic instability and persistent bleeding at the end of operation. Satisfactory postoperative pain control was achieved by continuous remifentanil (0.0125 to 0.05 microg x kg(-1) x min(-1)).

RESULTS

Operating theater extubation within 10 minutes of the end of operation was feasible in 150 patients (94%). Five patients (3%) were extubated within 2 hours, and the remaining 5 patients (3%) were converted to standard anesthesia. There were no deaths during hospitalization. Major complications included myocardial infarction and transient ischemic attacks (2 patients each). No pulmonary complications were seen. Episodes of atrial fibrillation occurred in 21% of the patients undergoing operation.

CONCLUSIONS

Immediate extubation is possible in most patients after off-pump coronary artery bypass grafting even without thoracic epidural analgesia. We believe this type of less invasive cardiac anesthesia is safe and promising.