Sevoflurane vs. propofol in patients with coronary disease undergoing mitral surgery: a randomised study.

BACKGROUND: Myocardial ischemic damage is reduced by volatile anaesthetics in patients undergoing low-risk coronary artery bypass graft surgery; few and discordant results exist in other settings. We therefore performed a randomised controlled trial (sevoflurane vs. propofol) to compare cardiac troponin release in patients with coronary disease undergoing mitral surgery. METHODS: Patients with coronary artery disease undergoing mitral surgery were randomly allocated to receive either sevoflurane (50 patients) or propofol (50 patients) as main hypnotic. The primary endpoint of the study was peak post-operative cardiac troponin release defined as the maximum value among the post-operative values measured at intensive care unit arrival, 4 h later, on the first and second post-operative day. RESULTS: There was no significant difference in post-operative peak troponin release, the median (25th-75th percentiles) values being 14.9 (10.1-22.1) ng/ml and 14.5 (8.8-17.6) ng/ml in the sevoflurane and propofol groups, respectively (P = 0.4). Fentanyl administration was different between the two groups: 1347 ± 447 µg in patients receiving sevoflurane and 1670 ± 469 µg in those receiving propofol, P = 0.002. The 1-year follow-up identified two patients who died in the propofol group (one myocardial infarction and one low cardiac output syndrome) and one in the sevoflurane group (myocardial infarction). CONCLUSION: In this study, patients with coronary artery disease undergoing mitral surgery did not benefit from the cardioprotective properties of halogenated anaesthetics. Sevoflurane anaesthesia was not associated to lower cardiac troponin release when compared with propofol anaesthesia.

Does clonidine 50 microg improve cervical plexus block obtained with ropivacaine 150 mg for carotid endarterectomy? A randomized, double-blinded study.

STUDY OBJECTIVE: To evaluate the effects of adding 50 microg clonidine to 150 mg ropivacaine for superficial cervical plexus block in patients undergoing elective carotid endarterectomy (TEA). DESIGN: Randomized, double-blind study. SETTING: Departments of Anesthesia and Vascular Surgery of a university hospital. PATIENTS: 40 ASA physical status II and III patients undergoing elective TEA during superficial cervical plexus block. INTERVENTIONS: Superficial cervical plexus block was placed using 20 mL of 0.75% ropivacaine alone (Ropi group, n = 20) or with the addition of 50 microg clonidine (Ropi-Clonidine group, n = 20). If required, analgesic supplementation was given with local infiltration with 1% lidocaine and intravenous fentanyl (50-microg boluses). Nerve block profile, need for intraoperative analgesic supplementation, and time to first analgesic request were recorded. MEASUREMENTS AND MAIN RESULTS: Median (range) onset time was 10 minutes (5-25 min) in the Ropi group and 5 minutes (5-20 min) in the Ropi-Clonidine group (P < 0.05). Intraoperative consumption of both 1% lidocaine and fentanyl was higher in patients of the Ropi group (15 mL [0-25 mL] and 250 microg [50-300 microg]) than in patients of the Ropi-Clonidine group (8 mL [0-20 mL] and 0 microg [0-150 microg]; P < 0.05 and P < 0.05, respectively). First postoperative analgesic request occurred after 17 hours (10-24 hrs) in the Ropi group and 20 hours (10-24 hrs) in the Ropi-Clonidine group (P > 0.05). CONCLUSIONS: Adding 50 microg clonidine to 150 mg ropivacaine for superficial cervical plexus block shortened the onset time and improved the quality of surgical anesthesia in patients undergoing elective TEA.

A prospective, randomized, blinded comparison between continuous thoracic paravertebral and epidural infusion of 0.2% ropivacaine after lung resection surgery.

BACKGROUND: The aim of this prospective, randomized, blinded study was to compare analgesic efficacy of continuous paravertebral and epidural analgesia for post-thoracotomy pain. METHODS: Forty-two ASA physical status II-III patients undergoing lung resection surgery were randomly allocated to receive post-thoracotomy analgesia with either a thoracic epidural (group EPI, n = 21) or paravertebral (group PVB, n = 21) infusion of 0.2% ropivacaine (infusion rate: 5-10 mL h-1). The degree of pain at rest and during coughing, haemodynamic variables and blood gas analysis were recorded every 12 h for the first 48 h. RESULTS: The area under the curve of the visual analogue pain score during coughing over time was 192 (60-444) cm h-1 in group EPI and 228 (72-456) cm h-1 in group PVB (P = 0.29). Rescue morphine analgesia was required in four patients of group EPI (19%) and five patients of group PVB (23%) (P = 0.99). The PaO2/FiO2 ratio reduced significantly from baseline values in both groups without between-group differences. The median (range) percentage reduction of systolic arterial pressure from baseline was -9 (0 to -9)% in group PVB and -17 (0 to -38)% in group EPI (P = 0.02); while clinically relevant hypotension (systolic arterial pressure decrease >30% of baseline) was observed in four patients of group EPI only (19%) (P = 0.04). Patient satisfaction with the analgesia technique was 8.5 (8-9.8) cm in group EPI and 9 (7.5-10) cm in group PVB (P = 0.65). CONCLUSIONS: Continuous thoracic paravertebral analgesia is as effective as epidural blockade in controlling post-thoracotomy pain, but is associated with less haemodynamic effects.

Monitored anesthesia care.

According to the American Society of Anesthe-siologists (ASA), a monitored anesthesia care (MAC) is a planned procedure during which the patient undergoes local anesthesia together with sedation and analgesia. Actually MAC is the first choice in 10-30% of all the surgical procedures. The 3 fundamental elements and purposes of a conscious sedation during a MAC are: a safe sedation, the control of the patient anxiety and the pain control. The patients undergoing conscious sedation are able to answer to orders appropriately and to protect airways. Last but not least, another purpose of any MAC is to get the patient appropriately satisfied, allowing him to get his discharge as faster as possible. There are many surgical procedures which can be performed using a MAC. The patient consciousness evaluation is of extreme importance during the surgical procedure performed with MAC: to this purpose the clinical and electroencephalographic evaluations such as Bispectral Index are very useful. MAC can be obtained with the association of fast half-life drugs or drugs getting a clinical effect which can vary according to the surgical requirements, using an infusion regiment. Apart from the pharmacological choice, this procedure can be performed with patient controlled sedation techniques or with continued intravenous infusion or with target controlled infusion.