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

[Open heart surgery under acupuncture ? Decrypting a program broadcast on France 2]

OBJECTIVES

To analyze a clip from the program ? Acupuncture, osteopathy, hypnosis: do complementary medicines have superpowers ? about acupuncture as an anesthetic for surgical procedures in China. To propose a rational explanation for the phenomena observed. To describe the processes leading a public service broadcasting channel to offer this type of content at prime time and the potential consequences in terms of public health.

METHOD

Analysis using critical thinking attitudes and skills, along with a bibliographical search of Medline, Google Scholar and Cochrane Library databases.

RESULTS

The information delivered in the television clip is ambiguous. It does not allow the viewer to form an informed opinion on the relevance of acupuncture as an anesthetic for surgical procedures. It is reasonable to assume that the clip shows surgery performed with undisclosed epidural anesthesia coupled with mild intravenous anesthesia, sometimes performed in other countries. What needs to be highlighted here is the overestimation of acupuncture added to the protocol. The media tend to exaggerate the risks and expected effects of the treatments they report on, which can lead patients to turn to unproven therapies.

CONCLUSION

Broadcasting such a clip at prime time underlines the urgent need for the public and all health professionals to be trained in sorting and critically analyzing health information.

History of Cardiac Anesthesia in India

Before the 19th century, the heart was considered as a "no-go" area, although minor and superficial procedures were performed in the early 1800s. It was only in the later part of the century that surgical repair of the wounds of the cardiac chambers was attempted. Cardiac surgery came to India in the mid-20th century and the operations performed were minor and extracardiac. Initially, the surgeries were performed at a select few centers located at Mumbai, Vellore, Delhi, Chennai, and Kolkata. The anesthesiologists of an earlier era in India worked with limited facilities, and with their interest and devotion contributed immensely to the growth of the specialty of cardiac anesthesia. The progress was somewhat modest until the 1980s, when it started increasing rapidly and India caught up with the Western world by the turn of century. The progress was seen not only in the clinical field, but also in technology, teaching, and academic fields. This article presents an account of the progress in the field of cardiac anesthesia in India, and highlights the contribution of some of the dedicated anesthesiologists because of whom the specialty has reached the present stature.

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.

[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.

Effects of Pericardial Lidocaine on Hemodynamic Parameters and Responses in Dogs Anesthetized With Midazolam and Fentanyl

OBJECTIVE

Tachycardia during anesthesia should be avoided, especially during off-pump coronary artery bypass graft surgery. Decreasing heart rate without reducing cardiac contractility is an ideal goal. To achieve this, the authors attempted to block the cardiac nerves by pericardial administration of local anesthetic.

DESIGN

A prospective study.

SETTING

A laboratory.

PARTICIPANTS

Anesthetized, mechanically ventilated dogs (n = 69).

INTERVENTIONS

The pericardial space was infused with 2.5 or 5 mL of 1% lidocaine, 5 mL of 2% lidocaine, or normal saline solution. The hemodynamic changes and the cardiac responses to atropine or isoproterenol were measured during cardiac nerve blockade. To examine the inhibitory action of pericardial lidocaine on arrhythmias, an electrical fibrillator was installed. Furthermore, the blood level of lidocaine was measured.

MEASUREMENTS AND MAIN RESULTS

Pericardial injection of lidocaine significantly decreased heart rate without a change in stroke volume. Under pericardial lidocaine, the tachycardia response to isoproterenol was similar to that observed without pericardial lidocaine, but response to atropine was significantly reduced. Pericardial lidocaine increased the voltage thresholds for inducing arrhythmias and ventricular fibrillation. Intravenous injection of lidocaine elevated the plasma concentration of lidocaine immediately, whereas the plasma concentration peaked at 10 minutes after pericardial administration.

CONCLUSIONS

Pericardial lidocaine (1) decreased heart rate without affecting stroke volume, (2) preserved the tachycardiac response to isoproterenol but completely blocked the response to atropine, and (3) increased the voltage thresholds for arrhythmias and ventricular fibrillation induced by an electrical fibrillator. These results suggest that pericardial lidocaine may be useful for controlling heart rate during off-pump coronary artery bypass graft surgery.

Living with off-pump coronary artery surgery: evolution, development, and clinical potential for coronary heart disease patients

The enormous progress in interventional cardiology during the last 10 years has resulted in a major change in the spectrum of patients referred for coronary bypass surgery. These patients are older and sicker and frequently have had previous percutaneous coronary interventions. Consequently, cardiac surgery is responding by adding new surgical techniques: off-pump open-chest coronary bypass surgery (OPCAB), minithoracotomy bypass surgery, videothoracoscopic (robotic) procedures, etc. Several registries published to date have proved OPCAB to be safe and clinically effective. Randomized studies and meta-analysis research in this field provide scientific support and suggest that myocardial, renal, and neurological functions, amongst others, are better preserved by OPCAB than by classic techniques that use a cardiopulmonary bypass pump (CPB). Moreover, avoidance of CPB yields significantly reduced oxidative stress and systemic inflammatory response. This results in higher safety for ischemic heart disease patients undergoing revascularization, thus offsetting the propensity to lower costs. The present review examines the physiological advantages and clinical outcomes of this simple mode of myocardial revascularisation and evaluates the wider implications arising from its evolution.

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.

Conscious Cardiac Surgery With Cardiopulmonary Bypass Using Thoracic Epidural Anesthesia Without Endotracheal General Anesthesia

OBJECTIVE

The purpose of this study was to evaluate the feasibility of thoracic epidural anesthesia as an alternative technique to general anesthesia in patients undergoing cardiac surgery under cardiopulmonary bypass.

DESIGN

A prospective study.

SETTING

Tertiary referral heart hospital.

PARTICIPANTS

Eleven patients underwent cardiac surgical procedures requiring cardiopulmonary bypass under thoracic epidural anesthesia from February to April 2004.

INTERVENTIONS

An epidural catheter was inserted at C7 to T2 intervertebral space on the day before the operation. Subsequently, cardiac surgery was performed using cardiopulmonary bypass.

MEASUREMENTS AND RESULTS

The midsternotomy approach was used in all the patients. Anticoagulation was achieved with 300 units/kg of heparin. Under normothermic cardiopulmonary bypass, 6 patients underwent closure of atrial septal defect, 3 underwent valve replacements, and 2 underwent coronary artery bypass surgery combined with valve replacements. Soon after establishing cardiopulmonary bypass, all but 1 patient developed apnea, which was reversed after termination of cardiopulmonary bypass. The mean cardiopulmonary bypass time was 102 +/- 28 minutes, the aortic cross-clamp time was 58 +/- 28 minutes, and the total duration of surgery was 229 +/- 64 minutes. There was no mortality or morbidity in this series.

CONCLUSION

Cardiac surgical procedures requiring cardiopulmonary bypass may be performed under thoracic epidural anesthesia, without endotracheal general anesthesia.

Comparison of three anesthetic techniques for off-pump coronary artery bypass grafting: General anesthesia, combined general and high thoracic epidural anesthesia, or high thoracic epidural anesthesia alone

OBJECTIVE

This study compared general anesthesia (GA), combined GA plus thoracic epidural anesthesia (TEA), and TEA alone in patients scheduled for off-pump coronary artery bypass grafting.

DESIGN

Prospective, nonrandomized clinical study

SETTING

University hospital.

PARTICIPANTS

Ninety consenting patients undergoing beating-heart coronary artery revascularization with comparable coronary status and left ventricular function.

INTERVENTIONS

GA (n=30) was conducted with propofol, remifentanil, and cisatracurium or combined with TEA (GA+TEA, n=30) or TEA as the sole anesthetic with ropivacaine plus sufentanil (TEA, n=30).

MEASUREMENTS AND MAIN RESULTS

Groups were comparable regarding the surgical approaches and the number of anastomoses. Four patients (GA, n=2; GA+TEA, n=2) who required unplanned cardiopulmonary bypass, and 4 patients in the TEA group who underwent unexpected intubation because of pneumothorax (n=2), phrenic nerve palsy, or incomplete analgesia were excluded from further analysis. Intraoperative heart rate decreased significantly with both GA+TEA and TEA. None of the patients with TEA alone was admitted to the intensive care unit, they all were monitored on average for 6 hours postoperatively in the intermediate care unit and allowed to eat and drink as desired on admission. Postoperative pain scores were lower in both groups with TEA. There were no differences among groups in patients overall satisfaction.

CONCLUSION

Based on the authors data, all anesthetic techniques were equally safe from the clinicians standpoint. However, GA+TEA appeared to be most comprehensive, allowing for revascularization of any coronary artery, providing good hemodynamic stability and reliable postoperative pain relief. Nonetheless, the actual and potential risks of TEA during cardiac surgery should not be underestimated.