Etomidate-induced hypotension: a pathophysiological approach using arterial elastance.

INTRODUCTION: Anaesthesia frequently induces hypotension. Several recent studies have analysed arterial elastance (Ea) in order to describe clinical variations of mean arterial pressure (MAP). The objective of the study was to assess Ea to explain MAP variation following etomidate induction. METHODS: We conducted a prospective single-centre study. Inclusion criteria were patients undergoing elective cardiac surgery with invasive blood pressure monitoring. Ea was expressed as Pes/SV (Pes: end systolic pressure, SV: stroke volume). Cardiac index (CI), peripheral vascular resistance (PVR) and arterial compliance (C) was compared before and 2 minutes after etomidate induction. Arterial hypotension was defined as a decrease greater than 15% of the baseline MAP. RESULTS: Of the 45 patients included, 24 (53%) had a preserved MAP and 21 (47%) had an etomidate-induced hypotension. Ea was similar before induction and decreased in the decreased MAP group 2 minutes after induction (2.0 mmHg.ml-1 [1.7-2.4] vs 1.4 mmHg.ml-1 [0.9-1.9]; p = 0.001). Arterial compliance (C) increased in the decreased MAP group 2 minutes after induction (0.8 ml. mmHg-1 [0.6-1.0] vs 0.5 ml. mmHg-1 [0.4-0.6], p < 0.0001). No significant change in CI or PVR was observed between patients with or without etomidate-induced hypotension. CONCLUSION: Etomidate-induced hypotension was associated to a decrease in Ea. Ea variations can mainly be explained by induced changes in arterial compliance.

"Killer coronary artery" and aortic valve stenosis: A tricky case.

Anomalous origin of the left main coronary artery from the right coronary sinus is rarely diagnosed in elderly patients. We report such an anomaly in a 75-year-old lady presenting with chest pain and syncope. Preoperative screening revealed that her aortic valve was moderately stenotic. The patient underwent a successful unroofing procedure combined with aortic valve replacement. The outcome was uncomplicated and the patient remained asymptomatic at one year postoperatively.

Respiratory variations of R-wave amplitude in lead II are correlated with stroke volume variations evaluated by transesophageal Doppler echocardiography.

OBJECTIVE: The authors hypothesized that variations in electrocardiographically derived R-wave amplitude might be correlated with mechanical ventilation-induced variations in stroke volume as determined by transesophageal echocardiography. DESIGN: Observational prospective study. SETTING: Single university hospital. PARTICIPANTS: Thirty-four patients undergoing coronary artery bypass surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Respiratory R-wave variations in lead II (ΔRII) were correlated with aortic velocity time integral variations (r = 0.82, p < 0.0001). Respiratory R-wave variations in leads III and aVF and pulse pressure variation also were correlated with aortic velocity time integral variations (r = 0.49, p = 0.015; r = 0.61, p = 0.0016; and r = 0.72, p < 0.0001, respectively). R-wave respiratory variations in lead V(5) were not correlated with aortic velocity time integral variations. ΔRII was correlated with pulse pressure variation (r = 0.71, p < 0.0001). A ΔRII cutoff value of 15% accurately predicted stroke volume variations >15%, with a specificity of 92%, a sensitivity of 86%, a positive likelihood ratio of 11.1, a negative likelihood ratio of 0.15, a positive predictive value of 95%, and a negative predictive value of 80%. CONCLUSIONS: ΔRII is correlated with stroke volume variations as determined by transesophageal echocardiography in mechanically ventilated patients and can identify the stroke volume variation cutoff of 15%, previously determined to be the cutoff for volume responsiveness.

Restenosis in the coronary stent is an argument for the surgical myocardial revascularization.

BACKGROUND: This study will evaluate the difference between the frequency of restenosis in myocardial revascularization procedures by stents and CABG by coronarographic control after clinical criteria (angina). METHODS AND RESULTS: Out of the total of 6564 coronarographies performed (1999-2002) for diagnosis purposes, 3110 patients (44.8%) underwent myocardial revascularization procedures, PCI or CABG. PCI was performed in 981 patients (31%) and CABG in 1148 patients (37.3%). At the same time, we performed in our units 2067 surgical procedures, out of which 1148 (55%) revascularizations by CABG. The angiographic control for patients with myocardial revascularization by stent (55 patients) or CABG (50 patients) was performed by clinical criteria (angina reappears) on 105 patients. The restenosis we found in 47 patients (74.5%) treated by stent revascularization and in 29 patients from CABG procedures. In our study restenosis rate was 4.8% in patients with PCI and 2.5% in patients with CABG. CONCLUSIONS: Both surgical (CABG) and percutaneous coronary artery revascularization (PCI) have proved to be extremely effective in the treatment of patients with multivessel coronary disease. In our study restenosis rate was smaller in the patients with CABG than in the PCI group, taking into account the fact that we did not use drug eluting stent (DES) on a large scale. Results from the series of randomized trials (SOS, SIRIUS, ERACI, ARTS, BARI, etc.) have shown that the restenosis phenomenon is an apparent advantage in patients with DES. Restenosis prevention is a complex phenomenon (inflammation, procoagulation, cellular migration, etc.) and DES appearance opens a new era in PCI.