A multicentre observational study on management of general anaesthesia in elderly patients at high-risk of postoperative adverse outcomes.

INTRODUCTION: In elderly patients, goal-directed haemodynamic therapy (GDHT), depth of anaesthesia monitoring and lung-protective ventilation have been shown to improve postoperative outcomes. The aim of this study was to evaluate current practices concerning strategies of anaesthesia optimisation in patients aged≥75 years. PATIENTS AND METHODS: A multicentre observational study was performed from February to May 2015 in 23 French academic centres. On 30 consecutive days in each centre, patients≥75 years with at least one major comorbidity undergoing elective or emergency procedures (femoral-neck fractures surgery, intraperitoneal abdominal surgery or vascular surgery) were included. Patient characteristics and data related to GHDT, management of hypotension, monitoring of temperature and depth of anaesthesia, lung ventilation, point of care haemoglobin testing were collected. RESULTS: In total, 807 patients were included. Only 2% of patients [95% CI: 1-3] received GHDT in full accordance with guidelines. Depth of anaesthesia monitoring was largely performed (53% [95% CI: 50-56]). The multifaceted strategy of lung-protective ventilation combining low tidal volumes (6-8mL/kg), PEEP of 5-8cm cmH2O, and repeated recruitment manoeuvres, was performed in only 4% [95% CI: 3-5] of patients. A centre effect was a major determinant of variation concerning implementation of these strategies. DISCUSSION: In patients'≥75 years, strategies of anaesthesia optimisation are not in accordance with eligible guidelines. Implementation of these techniques varies independently of factors related to the patient or the type of surgery and may be dependent on the generated constraints.

Stepped wedge cluster randomised controlled trial to assess the effectiveness of an optimisation strategy for general anaesthesia on postoperative morbidity and mortality in elderly patients (the OPTI-AGED study): a study protocol.

INTRODUCTION: Elderly patients constitute an increasingly large proportion of the high-risk surgical group. In adult patients, several specific intraoperative approaches such as cardiac output-guided haemodynamic therapy, depth of anaesthesia monitoring (DAM) or lung-protective ventilation (LPV) are designed to reduce postoperative mortality and surgical complications. However, none of these approaches has been specifically performed in the elderly, and no evaluation of a multimodal optimisation strategy for general anaesthesia has been achieved in this population. AIMS: The objective of this study is to assess, in high-risk patients aged 75 years and over undergoing high-risk surgery, the effectiveness of combined optimisation of anaesthesia involving goal-directed haemodynamic therapy (GDHT), LPV and electroencephalographic DAM on postoperative morbidity and mortality. The primary outcome of the study is a composite criterion associating major postoperative complications and mortality occurring within the 30 first postoperative days. The secondary outcomes are 1-year postoperative autonomy and mortality. METHODS AND ANALYSIS: This prospective, randomised, controlled, multicentre trial using a stepped wedge cluster design will be conducted in 27 French university centres. Patients aged 75 years and over, undergoing femoral head fractures and major intraperitoneal or vascular elective surgeries will be included after informed consent. They will benefit from usual care in the 'control group' and from a combined optimisation of general anaesthesia involving GDHT, LPV and DAM in the 'optimisation group'. The cluster's crossover will be unidirectional, from control to optimisation, and randomised. Data will be recorded at inclusion, the day of surgery, 7 days, 30 days and 1year postoperatively and collected into a hosted electronic case report form. The primary outcome of the study is a composite criterion associating major postoperative complications and mortality occurring within the 30 first postoperative days. The secondary outcomes are 1- year postoperative autonomy and mortality. ETHICS AND DISSEMINATION: This protocol was approved by the ethics committee Sud-Est 1 and the French regulatory agency. The finding of the trial will be disseminated through peer-reviewed journals and conferences TRIAL REGISTRATION NUMBER: NCT02668250; Pre-results.

Does spectral entropy reflect the response to intubation or incision during propofol-remifentanil anesthesia?

BACKGROUND: Spectral entropy is an electroencephalogram-based monitoring technique with a frequency band enlarged to include the electromyogram spectrum, which is intended to help to assess analgesia. Although its correlation with hypnosis has been shown, its performance during a noxious stimulation and the influence of neuromuscular blockade have not been described. METHODS: In this prospective, open, multicenter study, 105 patients received propofol then remifentanil target-controlled infusion for induction of anesthesia, with randomized remifentanil targets ranging from 2 to 8 ng/mL. Half of the patients received neuromuscular blockade. Intubation and incision were used as standard noxious stimulations, motor or hemodynamic responses were recorded, and spectral entropy values before and after stimulations were compared between responders and nonresponders. RESULTS: No difference was found in response entropy (RE), state entropy (SE), or (RE - SE) between patients with or without hemodynamic response to stimulations. Patients with motor response to intubation had higher values of RE, SE, and (RE - SE) both before and after the intubation than patients with no response. These results were confirmed by a prediction probability analysis, showing a significant but weak predictive value of entropy for motor response only. CONCLUSIONS: Entropy predicted a motor response to noxious stimulations but not a hemodynamic response, which limits its usefulness for assessing the analgesic component of anesthesia in paralyzed patients. High values (RE >55) before the stimulation should be avoided in order to decrease the risk of motor response, but lower values might not prevent this response when the opioid concentration is insufficient, despite an adequate hypnosis.

A comparison of target- and manually controlled infusion propofol and etomidate/desflurane anesthesia in elderly patients undergoing hip fracture surgery.

Elderly patients have a higher risk of developing adverse drug reactions during anesthesia, especially anesthesia affecting cardiovascular performance. In this prospective randomized study we compared quality of induction, hemodynamics, and recovery in elderly patients scheduled for hip fracture surgery and receiving either etomidate/desflurane (ETO/DES) or target-controlled (TCI) or manually controlled (MAN) propofol infusion for anesthesia. Sixteen patients were anesthetized with ETO (0.4 mg/kg) followed by DES titrated from an initial end-tidal concentration of 2.5%. Eighteen patients received propofol TCI at an initial plasma concentration of 1 microg/mL and titrated upwards by 0.5-microg/mL steps. Fifteen patients received a bolus induction of propofol 1 mg/kg over 60 s followed by an infusion initially set at 5 mg . kg(-1) . h(-1). All received a bolus (20 microg/kg) followed by an infusion of 0.4 microg . kg(-1) . min(-1) alfentanil. According to hemodynamics, concentrations of DES or propofol (TCI group) and propofol infusion rate (MAN group) were respectively adjusted by a step of 20% and 50%. In the TCI and ETO/DES groups, the time spent at a mean arterial blood pressure within 15% and 30% of baseline values was more than 60% and 80% of anesthesia time, whereas in the MAN group it was <30% and 60%, respectively. In the MAN group more anesthetic drug adjustments were recorded (6.4 +/- 2.8 versus 2.5 +/- 1.2 [ETO/DES] and 2.6 +/- 1 [TCI]). TCI improves the time course of propofol's hemodynamic effects in elderly patients.

Target-controlled versus manually-controlled infusion of propofol for direct laryngoscopy and bronchoscopy.

UNLABELLED: Few studies have compared the clinical profile of target-controlled infusions of propofol with that of manually-controlled infusions. Fifty-four ASA physical status I or II patients scheduled for an elective otorhinolaryngology endoscopy performed under general anesthesia with spontaneous ventilation were enrolled in this prospective randomized study to compare the clinical outcome of such administrations. Before induction, all patients received a single alfentanil bolus dose (10 microg/kg). Propofol administration was adapted to maintain absence of movement, hemodynamic stability, and efficient spontaneous ventilation. When compared with the Manually-Controlled Infusion group, in the Target-Controlled Infusion group there were fewer movements at insertion of the laryngoscope (14.8% vs. 44.4%), improved hemodynamic stability (largest variations of mean arterial blood pressure <10% of control values, versus 20%), fewer episodes of apnea, and less respiratory acidosis after endoscopy (pH = 7.37 +/- 0.05 and PaCO(2) = 50 +/- 7 mm Hg versus pH = 7.28 +/- 0.06 and PaCO(2) = 58 +/- 9 mm Hg); the recovery was also shorter (time to opening eyes or verbal response, 4.6 +/- 2.0 min and 6.8 +/- 2.5 min versus 10.8 +/- 7.3 min and 15.7 +/- 7.1 min). Propofol consumption was comparable in the two groups. Targeting the effect-site concentration improved the time course of the propofol drug effect during direct laryngoscopy performed during spontaneous ventilation when compared with manual infusion. IMPLICATIONS: This study compares the clinical profile of propofol anesthesia for direct laryngoscopy with spontaneous ventilation when the drug is administered either as a manually controlled infusion or by targeting the effect-site concentration through a target-controlled infusion (TCI) device. TCI improves the time course of propofol effects.