Low Target Sufentanil Effect-Site Concentrations Allow Early Extubation After Valve Surgery

Effects of norepinephrine infusion during cardiopulmonary bypass on perioperative changes in lactic acid level (Norcal)

INTRODUCTION

Hyperlactatemia, a problem reported in up to 30% of cardiac surgery patients, results from excessive production of or decreased clearance of lactate. It is typically a symptom of tissue hypoperfusion and may be associated with the prevalence of postoperative acute mesenteric ischemia and renal failure, or prolonged intensive care unit (ICU) and hospital stay, and increased 30-day mortality.

METHODS AND MEASUREMENTS

Eighty cardiac surgery patients using cardiopulmonary bypass (CPB) were randomly assigned into either a placebo (n = 39) or norepinephrine 0.05-0.2 µg/kg/min (n = 41) as well as norepinephrine boluses during CPB to maintain mean arterial blood pressure (MAP) at 65 to 80 mm Hg. Patient assignments were done after receiving ethical approval to proceed. The primary result was the perioperative changes in lactic acid level. Secondary findings were also recorded, including hemodynamic variables, the incidence of vasoplegia, intraoperative hypotension, myocardial ischemia, the need for vasopressor support, postoperative complications, and mortality.

RESULTS

The peak levels and perioperative changes in blood lactate during the first 24 postoperative hours, the number of patients who experienced early hyperlactatemia on admission to the ICU (Placebo: 46.2%, Norepinephrine: 51.2%, p = .650), vasoplegia, hemodynamic changes, incidences of intraoperative hypotension, myocardial ischemia, postoperative complications, and mortality rates were similar in the two groups. Patients in the norepinephrine group received lower intraoperative rescue norepinephrine boluses to maintain the target MAP (p = .039) and had higher MAP values during the CPB and intraoperative blood loss [mean difference [95% confidence interval]; 177 [20.9-334.3] ml, p = .027].

CONCLUSION

norepinephrine and placebo infusions during the CPB with the maintenance of MAP from 65 to 80 mmHg had comparative effects on the changes in blood lactate and incidence of vasoplegia after cardiac surgery. Norepinephrine infusion maintained higher MAP values during the CPB.

Malewicz N, Ebel M, K. Zahn P, H. Meyer-Frießem C. Pupillometric Monitoring of Nociception in Cardiac Anesthesia

BACKGROUND

High-dose opioids are conventionally used for cardiac anesthesia, but without monitoring of nociception. In non-cardiac surgical procedures the intra - operative dose of opioids can be individualized and reduced with pupillometric monitoring of the pupillary pain index (PPI; scale 1-9). A randomized controlled trial was carried out to explore whether pupillometry can be used for nociception monitoring in cardiac anesthesia and whether it leads to opioid reduction.

METHODS

A sample of 57 cardiac surgery patients receiving continuously administered sufentanil (initial dosage 0.7 μg*kg-¹*h-¹) was divided into a PPI group (sufentanil reduction if PPI<3 up to a minimum of 0.15 μg*kg-¹*h-¹, n=32) and a control group (standard anesthesia; n = 25). The primary outcome was the time from the end of anesthesia to extubation. The secondary outcomes were total intraoperative dose of sufentanil/noradrenaline, postoperative pain intensity (numeric rating scale [NRS] 0-10) and intraoperative awareness. German Clinical Trials Registry no. DRKS 00012329.

RESULTS

The primary outcome, extubation time, did not differ between the two groups (1.14 h, 95% confidence interval [-0.99; 3.27], p = 0.592). Compared with the control patients (68% male, age 70 ± 10.4 years, PPI 1.1 ± 0.2), the mean sufentanil infusion rate in the PPI patients (81% male, age 68 ± 10.3 years, PPI 1.1 ± 0.2) decreased by 81.8% (-0.68 μg*kg-¹*h-¹ [-0,7; -0.67], p<0.001) to the predetermined minimum level, without intraoperative awareness. Moreover, the noradrenaline dose was reduced by 56% (1235.51 μg [321.91; 2149.12], p = 0.005) and the postoperative pain intensity by 45% (2.11 NRS [0.93; 3.3] after 24 h, p = 0.003).

CONCLUSION

Pupillometry is appropriate for nociception monitoring in cardiac anesthesia. Thereby a considerable reduction of intraoperative opioids as well as increased intraoperative hemodynamic stability was achieved and postoperative opioid-induced hyperalgesia was prevented. The consistently low PPI scores, indicating adequate analgesia, suggest that further reduction of opioid doses is feasible.

A Comparison of Different Remifentanil Effect-Site Concentrations to Allow for Early Extubation After Cardiac Surgery

OBJECTIVES

Assess different remifentanil effect-site concentrations (Ce) for readiness for extubation time after cardiac surgery.

DESIGN

Prospective, randomized, blinded, controlled study.

DESIGN

Single university hospital.

PARTICIPANTS

Seventy-three patients scheduled for cardiac surgery.

INTERVENTIONS

After ethical approval, patients scheduled for cardiac surgery with target-controlled propofol infusion were randomly assigned to receive remifentanil effect-site concentrations (Ce) of 1, 2, or 3 ng/mL (n = 25, 25, and 23, respectively).

MEASUREMENTS AND MAIN RESULTS

The primary endpoint was readiness for extubation. Secondary outcomes were also recorded, including the cumulative doses and number of changes of propofol and remifentanil, hemodynamic variables, time to spontaneous eye opening and breathing, actual extubation, incidences of light anesthesia and myocardial ischemia, need for vasopressors and inotropes, and intensive care unit (ICU) and hospital stays. There was no difference in the time to readiness for extubation in any of the groups (0.1 ng/mL: 11.5 min (5-37); 0.2 ng/mL: 22 min (10-35); and 0.3 ng/mL: 21 min (10-49), p < 0.532); however, there was a significant difference among the 3 groups regarding the cumulative remifentanil doses (p < 0.001). Time to spontaneous eye opening and breathing, actual extubation, use of vasopressors and inotropes, incidences of light anesthesia and myocardial ischemia, and length of ICU and hospital stay were similar for all groups. Forty-six of the 73 patients were extubated on-table.

CONCLUSION

Remifentanil Ce 1, 2, and 3 ng/mL produced comparative effects on time to extubation and hemodynamic responses to cardiac surgery. The 3 Ce resulted in immediate on-table extubation in 50% of patients.

Factors associated with early extubation of patients after corrective tetralogy of Fallot

OBJECTIVE

To assess surgical management and postoperative results associated with early extubation in patients undergoing tetralogy of Fallot corrective surgery at a public hospital in Argentina.

METHODS

A retrospective review was made from clinical records from patients who underwent corrective surgery for tetralogy of Fallot. A total of 38 clinical records that met the inclusion criteria for the retrospective review were included in the analysis.

RESULTS

16% were extubated early. Milrinone was the only drug that showed differences in patients who were extubated early (p=0.01). Extracorporeal circulation time, aortic clamping time, transfusion with cryoprecipitates, saturation of oxygen pressure, and haematocrit at the end of the surgical procedure showed no differences (p>.05). In the postoperative period, the ICU stay was shorter for the patients who were extubated early (p=0.0007), but there were no differences in the total hospital stay (p=0.26).

CONCLUSIONS

Early extubation in the institution, although found to be low frequency, has proved as a safe and effective alternative to shorten these patients' stay in ICU.

Lower Dose of Sufentanil Does Not Enhance Fast Track Significantly-A Randomized Study

OBJECTIVE

Adjustment in the doses of opioids has been a focus of interest for achieving better fast-track conditions in cardiac anesthesia, but relatively sparse information exists on the potential effect of psychologic and behavioral factors, such as stress, anxiety, and type of personality, on anesthesia requirements and patient turnover in the cardiac recovery unit (CRU); to the authors' knowledge, this particular focus has not been systematically investigated. In this randomized study, the authors tested the hypothesis that low-dose sufentanil, compared with a standard dose, can improve fast-track parameters and the overall quality of recovery. Opioid requirements related to personality type, pain sensitivity, and preoperative stress and anxiety also were assessed.

DESIGN

A randomized, prospective study.

PARTICIPANTS

The study comprised 60 patients scheduled for elective coronary artery bypass grafting with or without aortic valve replacement.

SETTING

A university hospital.

INTERVENTIONS

Patients were randomly assigned to receive either a standard dose (bolus 0.5 µg/kg) or low dose (bolus 0.25 µg/kg) of sufentanil combined with propofol.

MEASUREMENTS AND MAIN RESULTS

The primary outcome variables were ventilation time and eligible time to discharge from the CRU. The secondary objective was to evaluate the relationship between opioid requirements and personality type, pain sensitivity, and preoperative stress and anxiety. The groups were comparable in selected demographics and perioperative parameters. There was no difference between groups in ventilation time (low dose: 191 [163-257] v standard dose: 205 [139-279] min; p = 0.405); eligible CRU discharge time (10.3 ± 5.0 v 10.3 ± 4.2 h; p = 0.978); or administration of postoperative morphine (25 [11-34) v 27 [10-39] g; p = 0.790). There was no difference between groups in total sufentanil administration and various preoperative psychologic and behavioral test levels nor in the time to reach bispectral index <50 during induction, except that personality type A demonstrated a longer induction time of 10 (8-12) minutes versus 6 (4-8) minutes in low-score patients.

CONCLUSION

A lower dose of sufentanil, compared with a standard dose, does not enhance fast-track conditions significantly.

Fast-track cardiac care for adult cardiac surgical patients

BACKGROUND

Fast-track cardiac care is a complex intervention involving several components of care during cardiac anaesthesia and in the postoperative period, with the ultimate aim of early extubation after surgery, to reduce length of stay in the intensive care unit and in the hospital. Safe and effective fast-track cardiac care may reduce hospital costs. This is an update of a Cochrane review first published in 2003, updated in 2012 and updated now in 2016.

OBJECTIVES

To determine the safety and effectiveness of fast-track cardiac care compared with conventional (not fast-track) care in adult patients undergoing cardiac surgery. Fast-track cardiac care intervention includes administration of low-dose opioid-based general anaesthesia or use of a time-directed extubation protocol, or both.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 5), MEDLINE (January 2012 to May 2015), Embase (January 2012 to May 2015), the Cumulative Index to Nursing and Allied Health Literature (CINAHL; January 2012 to May 2015) and the Institute for Scientific Information (ISI) Web of Science (January 2012 to May 2015), along with reference lists of articles, to identify additional trials. We applied no language restrictions.

SELECTION CRITERIA

We included all randomized controlled trials of adult cardiac surgical patients (coronary artery bypass grafts, aortic valve replacement, mitral valve replacement) that compared fast-track cardiac care and conventional (not fast-track) care groups. We focused on the following fast-track interventions, which were designed for early extubation after surgery: administration of low-dose opioid-based general anaesthesia during cardiac surgery and use of a time-directed extubation protocol after surgery. The primary outcome was risk of mortality. Secondary outcomes included postoperative complications, reintubation within 24 hours of surgery, time to extubation, length of stay in the intensive care unit and in the hospital, quality of life after surgery and hospital costs.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted study data. We contacted study authors for additional information. We calculated a Peto odds ratio (OR) for risk of mortality and used a random-effects model to report risk ratio (RR), mean difference (MD) and 95% confidence intervals (95% CIs) for all secondary outcomes.

MAIN RESULTS

We included 28 trials (4438 participants) in the updated review. We considered most participants to be at low to moderate risk of death after surgery. We assessed two studies as having low risk of bias and 11 studies high risk of bias. Investigators reported no differences in risk of mortality within the first year after surgery between low-dose versus high-dose opioid-based general anaesthesia groups (OR 0.53, 95% CI 0.25 to 1.12; eight trials, 1994 participants, low level of evidence) and between a time-directed extubation protocol versus usual care (OR 0.80, 95% CI 0.45 to 1.45; 10 trials, 1802 participants, low level of evidence).Researchers noted no significant differences between low-dose and high-dose opioid-based anaesthesia groups in the following postoperative complications: myocardial infarction (RR 0.98, 95% CI 0.48 to 1.99; eight trials, 1683 participants, low level of evidence), stroke (RR 1.17, 95% CI 0.36 to 3.78; five trials, 562 participants, low level of evidence) and tracheal reintubation (RR 1.77, 95% CI 0.38 to 8.27; five trials, 594 participants, low level of evidence).Comparisons with usual care revealed no significant differences in the risk of postoperative complications associated with a time-directed extubation protocol: myocardial infarction (RR 0.59, 95% CI 0.27 to 1.31; eight trials, 1378 participants, low level of evidence), stroke (RR 0.85, 95% CI 0.33 to 2.16; 11 trials, 1646 participants, low level of evidence) and tracheal reintubation (RR 1.34, 95% CI 0.74 to 2.41; 12 trials, 1261 participants, low level of evidence).Although levels of heterogeneity were high, low-dose opioid anaesthesia was associated with reduced time to extubation (reduction of 4.3 to 10.5 hours, 14 trials, 2486 participants, low level of evidence) and length of stay in the intensive care unit (reduction of 0.4 to 7.0 hours, 12 trials, 1394 participants, low level of evidence). Use of a time-directed extubation protocol was associated with reduced time to extubation (reduction of 3.7 to 8.8 hours, 16 trials, 2024 participants, low level of evidence) and length of stay in the intensive care unit (reduction of 3.9 to 10.5 hours, 13 trials, 1888 participants, low level of evidence). However, these two fast-track care interventions were not associated with reduced total length of stay in the hospital (low level of evidence).

AUTHORS' CONCLUSIONS

Low-dose opioid-based general anaesthesia and time-directed extubation protocols for fast-track interventions have risks of mortality and major postoperative complications similar to those of conventional (not fast-track) care, and therefore appear to be safe for use in patients considered to be at low to moderate risk. These fast-track interventions reduced time to extubation and shortened length of stay in the intensive care unit but did not reduce length of stay in the hospital.

Target-Controlled Infusion of Remifentanil Without Muscle Relaxants Allows Acceptable Surgical Conditions During Thoracotomy Performed Under Sevoflurane Anesthesia

OBJECTIVES

To test the hypothesis that the use of a nonmuscle relaxant anesthetic technique (NMRT) during thoracotomy would be associated with comparable surgical conditions with the standard use of neuromuscular blocking drugs.

DESIGN

A prospective, randomized, single-blind, controlled study.

SETTING

A single university hospital.

PARTICIPANTS

Sixty-six patients scheduled for open thoracotomy under sevoflurane anesthesia with a target-controlled infusion (TCI) of remifentanil.

INTERVENTIONS

After ethical approval, patients were randomly assigned to receive cisatracurium or saline (n = 33 for each group) during the entire study period.

MEASUREMENTS AND MAIN RESULTS

The four-point ordinal surgical rating scale, the intubating conditions, the use of anesthetics and vasopressors, the incidence of light anesthesia (defined as an episode with state entropy values that exceeded 50 and/or mean arterial blood pressure and heart rate values that exceeded the baseline by 20% and lasted for more than 3 consecutive minutes), and the times to clinical recovery and postanesthesia care unit (PACU) discharge, hospital stays, and postoperative residual curarization (PORC) were recorded. Compared with the use of cisatracurium, the use of NMRT resulted in comparable good-to-excellent surgical rating scales (90.9% v 94.0%, respectively; p = 0.642), good-to-excellent laryngoscopy and endobronchial intubating conditions (93.9% v 100%, respectively; p>0.09), use of anesthetic and vasopressor medications, and hospital stays, together with shorter clinical recovery, extubation times (7.6 [95% CI 6.82 to 8.39] v 19.0 [95% CI 15.76 to 22.23] minutes, respectively; p<0.001), and PACU stays (37.4 [95% CI 35.09 to 39.79] v 70.9 [95% CI 56.90 to 84.91] minutes, respectively; p<0.001). The use of cisatracurium resulted in a nonstatistical number of light anesthesia episodes upon positioning, skin incision, and rib separation (p>0.624, with Fisher's exact test). There were no failed intubations in the 2 groups. No patient received cisatracurium in the NMRT group. Two patients (6.1%) in the cisatracurium group experienced PORC that required tracheal intubation in the PACU.

CONCLUSION

The use of TCI of remifentanil with NMRT offers acceptable laryngoscopy, intubating, and surgical conditions during sevoflurane anesthesia for open thoracotomy, especially when. the anesthesiologists have more than 10 years' experience.

Can entropy predict neurologic complications after cardiac surgery?

Electroencephalography can detect both cerebral ischemia/hypoxia and seizures and can measure hypnotic effects. The author reported two patients with left main coronary artery disease and myocardial infarction scheduled for urgent coronary artery bypass grafting surgery; they developed abrupt decreases in response entropy (RE) and state entropy (SE) values to isoelectric silence during target-controlled propofol-sufentanil anesthesia. After that, low RE and SE values persisted throughout the intraoperative period. Both patients showed delayed awakening after surgery and brain CT revealed nonhemorrhagic tempro-parietal cerebral infarctions. Intraoperative entropy-based monitoring could predict poor neurological outcome after cardiac surgery during target-controlled propofol and sufentanil anesthesia.