A survey of spinal and epidural techniques in adult cardiac surgery

Impact of high spinal anesthesia technique on fast-track strategy in cardiac surgery: retrospective study

BACKGROUND AND OBJECTIVES

Although high spinal anesthesia (HSA) has been used in cardiac surgery, the technique has not yet been widely accepted. This retrospective study was designed to investigate the impact of HSA technique on fast-track strategy in cardiac surgery.

METHODS

Elective cardiac surgery cases (n=1025) were divided into two groups: cases with HSA combined with general anesthesia (GA) (HSA group, n=188) and cases with GA only (GA group, n=837). In the HSA group, bupivacaine and morphine were intrathecally administered immediately before GA was induced. Outcomes included fast-track extubation (less than 6 hours), extubation in the operating room, fast-track discharge from the intensive care unit (ICU) (less than 48 hours) and hospital (less than 7 days).

RESULTS

In the HSA group, 60.1% were extubated in less than 6 hours after ICU admission, as compared with 39.9% in the GA group (p<0.001). In the HSA group, 33.0% were extubated in the operating room, as compared with 4.4% in the GA group (p<0.001). LOS in the ICU was less than 48 hours in 67.6% in the HSA group, as compared with 57.2% of those in the GA group (p=0.033). LOS in the hospital was less than 7 days in 63.3% in the HSA group, as compared with 53.5% in the GA group (p=0.084).

CONCLUSIONS

HSA technique combined with GA in cardiac surgery increased the rate of fast-track extubation (less than 6 hours) when compared with GA only.

Bilateral sternal infusion of ropivacaine and length of stay in ICU after cardiac surgery with increased respiratory risk: A randomised controlled trial

BACKGROUND

The continuous bilateral infusion of a local anaesthetic solution around the sternotomy wound (bilateral sternal) is an innovative technique for reducing pain after sternotomy.

OBJECTIVE

To assess the effects of the technique on the need for intensive care in cardiac patients at increased risk of respiratory complications.

DESIGN

Randomised, observer-blind controlled trial.

SETTING

Single centre, French University Hospital.

PATIENTS

In total, 120 adults scheduled for open-heart surgery, with one of the following conditions: age more than 75 years, BMI >30 kg m, chronic obstructive pulmonary disease, active smoking habit.

INTERVENTION

Either a bilateral sternal infusion of 0.2% ropivacaine (3 ml h through each catheter; 'intervention' group), or standardised care only ('control' group). Analgesia was provided with paracetamol and self-administered intravenous morphine.

MAIN OUTCOME MEASURES

The length of time to readiness for discharge from ICU, blindly assessed by a committee of experts.

RESULTS

No effect was found between groups for the primary outcome (P = 0.680, intention to treat); the median values were 42.4 and 37.7 h, respectively for the control and intervention groups (P = 0.873). Similar nonsignificant trends were noted for other postoperative delays. Significant effects favouring the intervention were noted for dynamic pain, patient satisfaction, occurrence of nausea and vomiting, occurrence of delirium or mental confusion and occurrence of pulmonary complications. In 12 patients, although no symptoms actually occurred, the total ropivacaine plasma level exceeded the lowest value for which neurological symptoms have been observed in healthy volunteers.

CONCLUSION

Because of a small size effect, and despite significant analgesic effects, this strategy failed to reduce the time spent in ICU.

TRIAL REGISTRATION

EudraCT (N°: 2012-005225-69); ClinicalTrials.gov (NCT01828788).

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.

Does Paravertebral Blockade Facilitate Immediate Extubation after Totally Endoscopic Robotic Mitral Valve Repair Surgery?

Objective

Immediate extubation of select patients in the operating room after cardiac surgery has been shown to be safe and may result in improved hemodynamics and decreased cost perioperatively. The aim of this study was to evaluate whether the addition of paravertebral blockade (PVB) to general anesthesia facilitates extubation in the operating room in patients undergoing totally endoscopic robotic mitral valve repair (TERMR).

Methods

A review of 65 consecutive patients who underwent TERMR between January 2012 and June 2013 at a single institution was conducted. Patients were divided into two groups, one group that received PVB and general anesthesia and a second group that received general anesthesia alone. The data analyzed included quantities of anesthetic administered during surgery and the location of extubation after surgery.

Results

A total of 34 patients received PVB and general anesthesia, whereas 31 received general anesthesia alone. The two groups had similar demographic and surgical data. Patients in the PVB and general anesthesia group were more likely to be extubated in the operating room (67.6%, n = 23 vs 41.9%, n = 13, P = 0.048) and required less intraoperative fentanyl (3.41 μg/kg vs 4.90 μg/kg, P = 0.006). There were no adverse perioperative events in either group related to PVB or extubation.

Conclusions

The addition of PVB to general anesthesia for perioperative pain control facilitated extubation in the operating room in patients undergoing TERMR. Paravertebral blockade allowed for lower intraoperative fentanyl dosing, which may account for the increased incidence of immediate extubation. A detailed prospective study is warranted.

Effects of high thoracic epidural anesthesia on mixed venous oxygen saturation in coronary artery bypass grafting surgery

Background

To investigate possible effects of high thoracic epidural anesthesia (HTEA) on mixed venous oxygen saturation (SvO₂) in coronary artery bypass grafting surgery (CABGS).

Material/Methods

Sixty-four patients scheduled for CABGS were randomly assigned to either test (HTEA) or control group. Standard balanced general anesthesia was applied in both groups. Mean arterial blood pressure (MAP), heart rate (HR), oxygen saturation (SpO₂), central venous pressure (CVP), cardiac output (CO), cardiac index (CI), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), mean pulmonary arterial pressure (PAP), pulmonary capillary wedge pressure (PCWP), pulmonary compliance (C), bispectral index (BIS), body temperature, SvO₂, hematocrit values were recorded before induction. Postoperative hemodynamic changes, inotropic agent, need for vasodilatation, transfusion and additional analgesics, recovery score, extubation time, visual analogue scale (VAS) values, duration of stay in intensive care unit (ICU) and hospital were recorded.

Results

Study groups were similar in SpO₂, CVP, PCWP, PAP, C, body temperature, BIS values, development of intraoperative bradycardia. In HTEA group, intraoperative MAP, SVR, PVR, need for transfusion were lower, whereas CO, CI, SvO₂, hematocrit values were higher (p<0.05). Postoperative MAP, HR, hypertension development, need for vasodilatator, transfusion, analgesics, extubation time, recovery data, duration of stay in ICU, hospital were lower in HTEA group (p<0.05). VAS score decreased in 30 minutes and 12 hours following extubation in HTEA and control group, respectively.

Conclusions

HTEA may improve balance between oxygen presentation and usage by suppressing neuroendocrin stress response; provide efficient postoperative analgesia, more stabile hemodynamic, respiratory conditions, lower duration of stay in ICU, hospital.

Regional anaesthesia in the patient receiving antithrombotic and antiplatelet therapy

The actual incidence of neurological dysfunction resulting from haemorrhagic complications associated with neuraxial block is unknown. Although the incidence cited in the literature is estimated to be <1 in 150,000 epidural and <1 in 220,000 spinal anaesthetics, recent 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 increases 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 unfractionated heparin or low molecular weight heparin). The decision to perform spinal or epidural anaesthesia/analgesia and the timing of catheter removal in a patient receiving antithrombotic therapy is made on an individual basis, weighing the small, although definite risk of spinal haematoma with the benefits of regional anaesthesia for a specific patient. Coagulation status should be optimized at the time of spinal or epidural needle/catheter placement, and the level of anticoagulation must be carefully monitored during the period of neuraxial catheterization. Indwelling catheters should not be removed in the presence of therapeutic anticoagulation, as this appears to significantly increase the risk of spinal haematoma. Vigilance in monitoring is critical to allow early evaluation of neurological dysfunction and prompt intervention. An understanding of the complexity of this issue is essential to patient management.

Continuous incisional infusion of local anesthetic in pediatric patients following open heart surgery

AIM

To determine the efficacy and safety of a continuous subcutaneous local anesthetic (LA) infusion in pediatric patients following open heart surgery.

BACKGROUND

The use of a continuous LA infusion has been shown to be beneficial following adult cardiac surgery. To date there are no studies in the pediatric population.

METHODS/MATERIALS

Using a prospective, randomized, and double blind design, we compared LA, either 0.25% levobupivacaine or bupivacaine (Treatment Group) to saline (Placebo Group) delivered subcutaneously via a continuous infusion for 72 h after open heart surgery in 72 patients. Requirements for postoperative analgesics and pain scores were recorded for 72 h and plasma levels of local anesthetic were measured. Secondary outcomes measures included time to first oral intake, time to first bowel movement, time to urinary catheter removal, length of stay, requirements for antiemetics and additional sedation.

RESULTS

Total morphine requirements over the first 24 h were less in the Treatment Group than the Placebo Group (0.05 mg x kg(-1) vs 0.2 mg x kg(-1), P = 0.007); this was true for all patient groups except those patients weighing less than 6.3 kg. The number of patients requiring no morphine was greater in the Treatment Group (7/35 vs 1/37, P = 0.02). The Treatment Group also received less midazolam, lorazepam, and ketorolac than the Placebo Group over 72 h due to the reduced clinical need for these agents in patients weighing less than 31 kg. There were no differences in secondary outcomes.

CONCLUSIONS

A continuous incisional infusion of LA reduced postoperative analgesic requirement and sedative use in pediatric patients undergoing a median sternotomy incision. Dosed at a maximum rate of 0.4 mg x kg(-1) x h(-1), a continuous incisional infusion of LA is effective and safe for up to 72 h, with plasma levels of local anesthetic well below the toxic threshold.

[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 morphine plus general anesthesia in cardiac surgery: effects on pulmonary function, postoperative analgesia, and plasma morphine concentration

OBJECTIVES

To evaluate the effects of intrathecal morphine on pulmonary function, analgesia, and morphine plasma concentrations after cardiac surgery.

INTRODUCTION

Lung dysfunction increases morbidity and mortality after cardiac surgery. Regional analgesia may improve pulmonary outcomes by reducing pain, but the occurrence of this benefit remains controversial.

METHODS

Forty-two patients were randomized for general anesthesia (control group n=22) or 400 microg of intrathecal morphine followed by general anesthesia (morphine group n=20). Postoperative analgesia was accomplished with an intravenous, patient-controlled morphine pump. Blood gas measurements, forced vital capacity (FVC), forced expiratory volume (FEV), and FVC/FEV ratio were obtained preoperatively, as well as on the first and second postoperative days. Pain at rest, profound inspiration, amount of coughing, morphine solicitation, consumption, and plasma morphine concentration were evaluated for 36 hours postoperatively. Statistical analyses were performed using the repeated measures ANOVA or Mann-Whiney tests (*p<0.05).

RESULTS

Both groups experienced reduced FVC postoperatively (3.24 L to 1.38 L in control group; 2.72 L to 1.18 L in morphine group), with no significant decreases observed between groups. The two groups also exhibited similar results for FEV1 (p=0.085), FEV1/FVC (p=0.68) and PaO2/FiO2 ratio (p=0.08). The morphine group reported less pain intensity (evaluated using a visual numeric scale), especially when coughing (18 hours postoperatively: control group= 4.73 and morphine group= 1.80, p=0.001). Cumulative morphine consumption was reduced after 18 hours in the morphine group (control group= 20.14 and morphine group= 14.20 mg, p=0.037). The plasma morphine concentration was also reduced in the morphine group 24 hours after surgery (control group= 15.87 ng.mL-1 and morphine group= 4.08 ng.mL-1, p=0.029).

CONCLUSIONS

Intrathecal morphine administration did not significantly alter pulmonary function; however, it improved patient analgesia and reduced morphine consumption and morphine plasma concentration.

Epidural analgesia in cardiac surgery: an updated risk assessment

INTRODUCTION

The use of epidural anesthesia carries risks that have been known for 50 years. The debate about the use of locoregional technique in cardiac anesthesia continues. The objective of this report is to estimate the risks and their variability of a catheter-related epidural hematoma in cardiac surgery patients and to compare it with other anesthetic and medical procedures.

METHODS

Case series reporting the use of epidural anesthesia in cardiac surgery were researched through Medline. Additional references were retrieved from the bibliography of published articles and from the internet. Risks of complications in other anesthetic and medical activity were retrieved from recent reviews.

RESULTS

Based on the present evidence, the risk of epidural hematoma in cardiac surgery is 1:12,000 (95% CI of 1:2100 to 1:68,000), which is comparable to the risk in the nonobstetrical population of 1:10,000 (95% CI 1:6700 to 1:14,900). The risk of epidural hematoma is comparable to the risk of receiving a wrong blood product or the yearly risk of having a fatal road accident in Western countries.

CONCLUSIONS

The risk of a hematoma after epidural in cardiac surgery is comparable to other nonobstetrical surgical procedures. Its routine application in a controlled setting should be encouraged.

The changes in coagulation profile and epidural catheter safety for living liver donors: a report on 6 years of our experience

The use of epidural catheters has been a subject of active debate in living liver donors because of the possible postoperative coagulation derangement and the subsequent risk of epidural hematoma. The aim of this study was to evaluate the safety of epidural catheters in relation to the changes in coagulation profile based on a review of previously published literature and the results of our 360 donors. In both the literature and in our cases, platelet count, prothrombin time (PT), and activated partial thromboplastin time (aPTT) in cases of heparin administration showed significant changes (P < 0.05), especially after right lobectomy. Platelet count reached its nadir on postoperative day (POD) 2-3, while PT and aPTT reached their peaks on POD 1-2 and at the end of the operation, respectively. In our donors, the ranges of platelet count, PT, and aPTT for the first 3 PODs were 54-359 x10/microL, 0.99-2.38 international normalized ratio (INR), and 25.9-300 seconds, respectively, and of note, 5 donors (1.4%) had a platelet count of <80 x 10/microL and 9 donors (2.5%) had a PT of >2.0 INR. Epidural catheterizations were performed in 242 donors, and the catheters were removed on POD 3-4 in 177 donors (73.1%). Mean (range) of platelet count, PT, and aPTT on the day of catheter removal were 168.4 +/- 42.9 (82-307) x 10/microL, 1.33 +/- 0.18 (0.99-1.93) INR, and 40.9 +/- 4.8 (32.0-70.6) seconds, respectively. No epidural hematoma was observed in this study. In conclusion, the discreet use of epidural catheters in live liver donors, in spite of postoperative coagulation derangements, appears to be safe regardless of the type of hepatectomy performed.

High thoracic epidural blockade increases myocardial oxygen availability in coronary surgery patients

BACKGROUND

High thoracic epidural techniques are increasingly being used in patients scheduled for cardiothoracic surgery, including coronary artery bypass grafting. In the present study, we evaluated the acute effects of the epidural blockade on myocardial oxygen availability by means of tissue oxygen pressure monitoring in patients submitted for surgical revascularization.

METHODS

Fifty adult patients were included in a prospective, randomized, double-blind study. After placement of an epidural catheter in thoracic space T1-T2, and under general anesthesia, 5-10 ml of either normal saline or 0.3% ropivacaine was injected through the epidural catheter. Hemodynamic parameters and the intramyocardial oxygen partial pressure were recorded before and 20 min after the epidural injection.

RESULTS

There were no demographic or hemodynamic differences between the groups before intervention. A significant increase in intramyocardial partial oxygen pressure was observed in the ropivacaine group (14.6 mmHg vs. 25.1 mmHg, P < 0.0005).

CONCLUSION

High thoracic epidural blockade with 5-10 ml of 0.3% ropivacaine increases myocardial oxygen availability in coronary diseased patients prior to surgical revascularization without deleterious hemodynamic disturbances.

Aortic valve replacement through a mini lateral thoracotomy with high thoracic epidural anesthesia

BACKGROUND

: Minimally invasive aortic valve surgery is usually performed through a right parasternal incision or a modification of partial sternotomy. We explored the feasibility of using a video-assisted small right lateral thoracotomy (RLT) to approach the aortic valve.

METHODS

: From August 2003 to December 2004, 12 patients with aortic stenosis (9) or regurgitation (3) underwent an aortic valve replacement through an 8 cm RLT in the 4th intercostal space. There were 4 men and 8 women with a mean age of 61 years (range 30-79 years). Nine mechanical and 3 biologic prostheses were implanted. Endotracheal narcosis was combined with high thoracic epidural anesthesia. Transesophageal echocardiographic monitoring was performed in all cases. Cannulation was done via the right femoral artery and vein and right jugular vein. The video-assisted operation was performed in moderate hypothermia (30°C) and in cardioplegic arrest. Transthoracic aortic clamping was used in all cases.

RESULTS

: Mean operation, perfusion, and clamping times were 223 minutes, 132 minutes, and 73 minutes, respectively. There was no mortality. One patient required conversion to sternotomy due to discovery of a calcium fragment entrapped in a mechanical prosthesis. One patient developed a groin seroma that was treated surgically. All patients, except one were extubated in the operative room and transferred to the intermediate care unit after 6 hours; all had an uneventful recovery.

CONCLUSIONS

: Aortic valve replacement through an RLT is feasible and safe. Operative time, perfusion, and cross-clamping times are only marginally longer than a conventional operation, and recovery is rapid.

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.

Postoperative Analgesia After Spinal Blockade in Infants and Children Undergoing Cardiac Surgery

The aim of this prospective, randomized, controlled clinical trial was to define the opioid analgesic requirement after a remifentanil (REMI)-based anesthetic with spinal anesthetic blockade (SAB+REMI) or without (REMI) spinal blockade for open-heart surgery in children. We enrolled 45 patients who were candidates for tracheal extubation in the operating room after cardiac surgery. Exclusion criteria included age <3 mo and >6 yr, pulmonary hypertension, congestive heart failure, contraindication to SAB, and failure to obtain informed consent. All patients had an inhaled induction with sevoflurane and maintenance of anesthesia with REMI and isoflurane (0.3% end-tidal). In addition, patients assigned to the SAB+REMI group received SAB with tetracaine (0.5-2.0 mg/kg) and morphine (7 mug/kg). After tracheal extubation in the operating room, patients received fentanyl 0.3 mug/kg IV every 10 min by patient-controlled analgesia for pain score = 4. Pain scores and fentanyl doses were recorded every hour for 24 h or until the patient was ready for discharge from the intensive care unit. Patients in the SAB+REMI group had significantly lower pain scores (P = 0.046 for the first 8 h; P =0.05 for 24 h) and received less IV fentanyl (P = 0.003 for the first 8 h; P = 0.004 for 24 h) than those in the REMI group. There were no intergroup differences in adverse effects, including hypotension, bradycardia, highest PaCO(2), lowest pH, episodes of oxygen desaturation, pruritus, and vomiting.

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.

Regional Anesthesia and Anticoagulation in Patients undergoing Cardiothoracic and Vascular Surgery

Spinal hematoma is a rare and potentially catastrophic complication of spinal or epidural anesthesia. The decision to perform spinal or epidural anesthesia or analgesia and the timing of catheter removal in a patient receiving antithrombotic therapy should be made on an individual basis, weighing the small, though definite risk of spinal hematoma with the benefits of regional anesthesia for a specific patient. Alternative anesthetic and analgesic techniques exist for patients considered an unacceptable risk. The patient's coagulation status should be optimized at the time the spinal or epidural needle or catheter is placed, and the level of anticoagulation must be carefully monitored during the period of epidural catheterization. Indwelling catheters should not be removed in the presence of therapeutic anticoagulation, as this appears to significantly increase the risk of spinal hematoma. Vigilance in monitoring is critical to allow early evaluation of neurologic dysfunction and prompt intervention.

Anaesthesia in parturients with heart disease: a five year review in an Australian tertiary hospital

At the Royal Women's Hospital, Queensland, between 1993 and 1997 there were 56 vaginal and 22 caesarean deliveries involving 68 women with heart disease. Over half of those women required anaesthetic input, in particular, the women who had the most serious cardiac compromise. There were two maternal deaths, four unbooked and five booked admissions to intensive or coronary care unit.

Thoracic epidural analgesia in coronary artery bypass graft surgery: seven years' experience

OBJECTIVE

To evaluate the risk of neurologic complications caused by an epidural hematoma in a series of patients who had coronary artery bypass graft surgery with cardiopulmonary bypass under combined general and thoracic epidural anesthesia (TEA).

DESIGN

Prospective observational study.

SETTING

General hospital associated with a university.

PARTICIPANTS

Seven hundred fourteen patients who had coronary artery bypass grafting surgery over a 7-year period.

INTERVENTIONS

An epidural catheter was inserted at T(1)-T(3) as soon as the patient was in the operating room and local anesthetic was administered as a bolus and then as a continuous infusion throughout the operation and postoperatively. A set of safety guidelines was routinely followed. A protocol for postoperative neurologic evaluation was used to rule out any signs of spinal compression.

MEASUREMENTS AND MAIN RESULTS

Preoperatively, a battery of coagulation tests was systematically performed including APTT, platelet count, and prothrombin time. Antiplatelet drugs (aspirin) were stopped at least 7 days before surgery. No patient required parenteral opiates postoperatively. Seventy-five percent of the patients were extubated in the operating room. No clinical epidural hematomas were detected.

CONCLUSION

In this study, some of the benefits previously reported during cardiac surgery under TEA, such as excellent analgesia and early extubation, were confirmed. In addition, the series adds further evidence that adherence to a set of standard safety measures, in this setting, averts the occurrence of symptomatic epidural hematomas.

Prospective randomized trial of high thoracic epidural analgesia for coronary artery bypass surgery

BACKGROUND

Postoperative pain may be severe after coronary artery bypass surgery. High thoracic epidural analgesia (HTEA) provides intense analgesia.

METHODS

Eighty patients were randomized to HTEA or intravenous morphine analgesia (control). Patients received coronary artery bypass surgery (CABG) with cardiopulmonary bypass. Pain was measured by visual analogue scale 0 to 10. Psychologic morbidity, intraoperative hemodynamics, ventricular function, lung function, and physiotherapy cooperation were also assessed. On the third postoperative day HTEA and morphine were ceased and only oral medications were used. Acetaminophen, indomethacin, and tramadol were allowed as supplemental analgesics in both groups.

RESULTS

The primary endpoint of pain scores was significantly less with HTEA on postoperative days 1 and 2 at rest, 0.02 +/- 0.2 versus 0.8 +/- 1.8 (p = 0.008) and 0.1 +/- 0.4 versus 1.2 +/- 2.7 (p = 0.022), respectively, and with coughing 1.2 +/- 1.7 versus 4.4 +/- 3.1 (p < 0.001) and 1.5 +/- 2.0 versus 3.6 +/- 3.1 (p = 0.001), respectively. When HTEA and morphine were ceased on day 3, there were no significant differences. The secondary endpoints of postoperative depression (p = 0.033) and posttraumatic stress subscales (p = 0.021) of the Minnesota Multiphasic Personality Inventory were lower with HTEA. Extubation occurred earlier with HTEA, 2.6 versus 5.4 hours (p < 0.001). HTEA showed improved physiotherapy cooperation (p < 0.001), arterial oxygen tension (p = 0.041), and peak expiratory flow rate (p = 0.001). Mean arterial pressure was lower with HTEA (p = 0.036), otherwise there were no differences in intraoperative hemodynamics or ventricular function.

CONCLUSIONS

Epidural analgesia reduces pain after coronary operation and is associated with improved physiotherapy cooperation, earlier extubation, and reduced risk of depression and posttraumatic stress.

A combination of intrathecal morphine and remifentanil anesthesia for fast-track cardiac anesthesia and surgery

OBJECTIVE

To determine if the combined remifentanil and intrathecal morphine (RITM) anesthetic technique facilitates early extubation in patients undergoing coronary artery bypass graft (CABG) surgery.

DESIGN

Prospective, randomized, controlled clinical trial.

SETTING

Referral center for cardiothoracic surgery at a university hospital.

PARTICIPANTS

Patients (n = 24) undergoing first-time elective CABG surgery.

INTERVENTIONS

Two groups represented RITM (n = 12) and fentanyl-based (controls, n = 12) anesthesia. Premedication was standardized to temazepam, 0.4 mg/kg, and anesthesia was induced with etomidate, 0.3 mg/kg, in both groups. The RITM group received remifentanil, 1 microg/kg bolus followed by 0.25 to 1 microg/kg/min infusion, and intrathecal morphine, 2 mg. The control group received fentanyl, 12 microg/kg in 3 divided doses. Anesthesia was maintained with isoflurane and pancuronium in both groups. After completion of surgery, the remifentanil infusion was stopped. Complete reversal of muscle relaxation was ensured with a nerve stimulator, and a propofol infusion, 0.5 to 3 mg/kg/h, was started in both groups. All patients were transferred to the intensive care unit (ICU) to receive standardized postoperative care. Intensivists and ICU nurses were blinded to the group assignment. Propofol infusion was stopped, and the tracheal extubation was accomplished when extubation criteria were fulfilled.

MEASUREMENTS AND MAIN RESULTS

Both groups were similar with respect to demographic data and surgical characteristics. Extubation times were 156 +/- 82 minutes and 258 +/- 91 minutes in the RITM and control groups (p = 0.012). Patients in the RITM group exhibited lower visual analog scale pain scores during the first 2 hours after extubation (p < 0.04). Morphine requirements during the 24 hours after extubation were 2.5 +/- 3 mg in the RITM group and 16 +/- 11 mg in the control group (p = 0.0018). Sedation scores were lower in the RITM group during the first 3 hours after extubation (p < 0.03). Pulmonary function tests as assessed by spirometry were better in the RITM group at 6 and 12 hours after extubation (p < 0.04). There were no significant differences in PaO(2) and PaCO(2) after extubation between the 2 groups. None of the patients had episodes of apnea during the immediate 24-hour postextubation period. Two patients from the RITM group required reintubation on the second and sixth postoperative days. There were no differences in ICU and hospital length of stay between the 2 groups.

CONCLUSION

Implementation of the RITM technique provided earlier tracheal extubation, decreased level of sedation, excellent analgesia, and improved spirometry in the early postoperative period. The impact of RITM on ICU and hospital length of stay and potential cost benefits require further evaluation.