Late Post-Conditioning with Sevoflurane after Cardiac Surgery--Are Surrogate Markers Associated with Clinical Outcome?

Efficacy of Sevoflurane and Propofol Anesthesia on Perioperative Adverse Cardiovascular Events and Hemodynamics in Elderly Patients With Diabetes

PURPOSE

This study was undertaken to compare the effects of sevoflurane and propofol anesthesia on perioperative hemodynamics and perioperative adverse cardiovascular events (PACE) in elderly patients with diabetes undergoing general anesthesia for noncardiac surgery.

METHODS

According to the random number table (n = 40), 80 patients with diabetes undergoing noncardiac general anesthesia were divided into a control group and an observation group. In the control group, the patients were given propofol 4 to 6 mg/(kg·h), continuously pumped to maintain anesthesia. In the observation group, the patients were given maintained concentration of sevoflurane for 1 to 1.5 minimum alveolar concentration (MAC) for continuous inhalation, while remifentanil with volume fraction of 0.05 to 1 µg/(kg·min) was given for continuous pumping in both groups. The heart rate (HR) and mean arterial pressure (MAP) of the patients were recorded, and the serum creatine kinase-MB (CK-MB) and cardiac troponin I (cTnI) contents before anesthesia (T0), immediately after surgery (T3), and 24 hours later (T4) as well as the blood glucose levels at T0 and T3 were compared between the two groups. The occurrence of PACE in the two groups was compared during the perioperative period.

FINDINGS

The HR and MAP 5 minutes after intubation (T1), 1 hour after skin incision (T2), and at T3 in the two groups were significantly lower than those of T0 (P < 0.05), whereas the MAP and HR of T1, T2, and T3 in the observation group were significantly higher than those of the control group (P < 0.05). The T3 blood glucose levels were significantly higher in the two groups than that in T0 (P < 0.05), and the T3 blood glucose levels in the observation group were significantly lower than that in the control group (P < 0.05). CK-MB and cTnI in the two groups were significantly higher at T3 and T4 than T0 (P < 0.05), whereas CK-MB and cTnI in the observation group were significantly lower than in the control group at T3 and T4 (P < 0.05). The incidence of hypotension and PACE was significantly lower in the observation group than in the control group (P < 0.05).

IMPLICATIONS

Compared with propofol IV general anesthesia, sevoflurane inhalation anesthesia can improve perioperative hemodynamics stability and reduce the incidence of PACE in elderly patients with diabetes undergoing noncardiac surgery.

Perioperative strategies to reduce risk of myocardial injury after non-cardiac surgery (MINS): A narrative review

Myocardial injury is a frequent complication of surgical patients after having non-cardiac surgery that is strongly associated with perioperative mortality. While intraoperative anesthesia-related deaths are exceedingly rare, about 1% of patients undergoing non-cardiac surgery die within the first 30 postoperative days. Given the number of surgeries performed annually, death following surgery is the second leading cause of death in the United States. Myocardial injury after non-cardiac surgery (MINS) is defined as an elevation in troponin concentrations within 30 days postoperatively. Although typically asymptomatic, patients with MINS suffer myocardial damage and have a 10% risk of death within 30 days after surgery and excess risks of mortality that persist during the first postoperative year. Many factors for the development of MINS are non-modifiable, such as preexistent coronary artery disease. Preventive measures, systematic approaches to surveillance and treatment standards are still lacking, however many factors are modifiable and should be considered in clinical practice: the importance of hemodynamic control, adequate oxygen supply, metabolic homeostasis, the use of perioperative medications such as statins, anti-thrombotic agents, beta-blockers, or anti-inflammatory agents, as well as some evidence regarding the choice of sedative and analgesic for anesthesia are discussed. Also, as age and complexity in comorbidities of the surgical patient population increase, there is an urgent need to identify patients at risk for MINS and develop prevention and treatment strategies. In this review, we provide an overview of current screening standards and promising preventive options in the perioperative setting and address knowledge gaps requiring further investigation.

An Exploratory Study of Sevoflurane as an Alternative for Difficult Sedation in Critically Ill Children

OBJECTIVES

To analyze the effectiveness of inhaled sevoflurane in critically ill children with challenging sedation.

DESIGN

Prospective case series.

SETTING

Two PICUs of university hospitals in Spain.

INTERVENTIONS

Prospective observational study and exploratory investigation conducted in two PICUs in Madrid, Spain, over a 6-year period. Children treated with inhaled sevoflurane due to difficult sedation were included. Sevoflurane was administered via the anesthetic conserving device (AnaConDa) connected to a Servo-I ventilator (Maquet, Solna, Sweden). A morphine infusion was added to sevoflurane for analgesia. Demographic and clinical data, oral and IV sedatives, Sedation and Analgesic Clinical scores, and Bispectral Index Score monitoring were registered.

MEASUREMENTS AND MAIN RESULTS

Twenty-three patients with a median age of 6 months old were included. Fifty percentage of the patients had critical heart diseases. Sedative and analgesic drugs used before starting sevoflurane were mainly midazolam (63%) and fentanyl (53%). Six patients (32%) also received muscle relaxants. Sevoflurane was administered for a median of 5 days (interquartile range, 5.5-8.5 d). Median end-tidal sevoflurane concentration was 0.8% (interquartile range, 0.7-0.85%), achieved with an infusion rate of 7.5 mL/hr (5.7-8.6 mL/hr). After 48 hours of treatment, some sedative drugs could be removed in 18 patients (78%). Median Bispectral Index Score value prior to sevoflurane administration was 61 (interquartile range, 49-62), falling to 42 (interquartile range, 41-47; p < 0.05) after 6 hours of treatment. Six patients (26%) presented withdrawal syndrome after sevoflurane suspension, and all of them had received sevoflurane at least for 6 days. The main side effect was moderate hypotension in seven patients (30%).

CONCLUSIONS

Inhaled sevoflurane appeared to be an effective sedative agent in critically ill children and can be useful in those patients on mechanical ventilation difficult to sedate with conventional drugs. It can be administered easily in the PICU with conventional ventilators using the AnaConDa system. Withdrawal syndrome may occur with prolonged treatment.

Randomized comparison of sevoflurane versus propofol-remifentanil on the cardioprotective effects in elderly patients with coronary heart disease

Background

It is skeptical about cardioprotective property of sevoflurane in patients undergoing noncardiac surgery, especially in the elderly patients with coronary heart disease. We hypothesized that long duration of sevoflurane inhalation in noncardiac surgery could ameliorate myocardial damage in such patients.

Methods

This was a randomized, prospective study. One hundred twenty-one elderly patients with coronary heart disease were randomly allocated into two groups. Maintenance of anesthesia was achieved by sevoflurane inhalation (Group S) or propofol-remifentanil respectively (Group PR). Serum cardiac troponin I (cTnI) and brain natriuretic peptide (BNP) were measured before anesthesia induction (T0), 8 h (T1) and 24 h (T2) after anesthesia respectively. The perioperative cardiac output, complications and postoperative 3-month follow-up from end of surgery were recorded.

Results

Between the two groups, there were no statistical differences in the values of cTnI and BNP during the study. However, The area under the curve of cTnI values over 24 h after operation was less in Group S. Group PR had lower cardiac output and consumed more amount of phenylephrine during the study (P < 0.05).

Conclusions

Compared with the group PR, sevoflurane had no benefit in the myocardial protection for the elderly patients with CHD. However, Sevoflurane showed advantage in maintaining hemodynamic stability during the operative period.

Trial registration

Chinese Clinical Trial Registry, ChiCTR-IPR-16008871, 21 July 2016.

[Cardioprotection in cardiac surgical patients : Everything good comes from the heart]

BACKGROUND

Despite substantial success in the anesthetic and surgical management of cardiac surgery, patients frequently show postoperative complications and organ dysfunctions. This is highly relevant for mid- to long-term outcomes.

OBJECTIVES

To evaluate cardioprotective strategies that may offer effective protection in vulnerable cardiac surgery patients.

METHODS

To demonstrate recent cardioprotective approaches for cardiac surgery patients, aiming to modulate the body's own protective mechanisms in cardiac surgery patients.

RESULTS

Both cardioplegia and hypothermia belong to the well-established protective strategies during myocardial ischemia. Volatile anesthetics have been repeatedly shown to improve the left ventricular function and reduce the extent of myocardial injury compared to a control group with intravenous anesthesia. Furthermore, patients receiving volatile anesthetics showed a significantly shortened stay in the ICU and in hospital after cardiac surgery. In contrast, numerous other protective strategies failed translation into the clinical practice. Despite the published reduction of troponin release after remote ischemic preconditioning, two recent large-scale randomized multicenter trials were unable to demonstrate a clinical benefit.

CONCLUSIONS

Beside the use of cardioplegia and hypothermia, the use of volatile anesthetics is well-established during cardiac surgery because of its conditioning and protective properties. Regardless of the promising results derived from experimental studies and small clinical trials, the majority of other approaches failed to translate their findings into the clinic. Therefore, systematic experimental studies are needed to identify potential confounding factors that may affect the protective effects.