ABSTRACT
BACKGROUND: As a rule, central venous catheters (CVC) should not be positioned in the right atrium (RA) to avoid the risk of perforation and cardiac tamponade. However, in ICUs where ECG monitoring can detect any initial damage of the atrial wall, CVCs may probably be safely positioned in the RA. We investigated whether mixed venous saturation (SvO2) was better estimated by measuring central venous saturation (ScvO2) in the RA or in the superior vena cava (SVC) in patients undergoing cardiac surgery. METHODS: A CVC and a pulmonary artery catheter (PAC) were positioned before surgical coronary revascularization in sixty patients. Under transesophageal echocardiographic guidance, CVC tips were randomly positioned inside the RA (group A) or the SVC (group C). In each patient, eight pairs of blood samples were collected from CVC and PAC distal ports and saturation measured. Cardiac arrhythmias that occurred in the first 48 postoperative hours and CVC tip position on chest X-rays were also registered. RESULTS: ScvO2 and SvO2 correlated better in group A (r=0.95) than in group C (r=0.84). The 95% interval of confidence of the gap between ScvO2 and SvO2 was narrower in group A (-6.9/+ 3.2 vs. -11.6/+5.5; p<.01). The incidence of arrhythmias was equal in the two groups (16.7%). On chest X-rays, CVC tips were 5.4 (SD=3.6) cm below the tracheal carina in group A and 5.3 (SD=3.9) cm in group C. CONCLUSION: In monitored patients, positioning CVC tips in the RA rather than in the SVC may allow closer estimates of SvO2 and may be safe. Yet, safety should be confirmed by further studies with larger samples of patients.
Subject(s)
Blood Specimen Collection/methods , Catheterization, Central Venous/methods , Central Venous Catheters , Heart Atria , Oxygen/blood , Vena Cava, Superior , Aged , Arrhythmias, Cardiac/epidemiology , Echocardiography, Transesophageal , Elective Surgical Procedures , Female , Hemodynamics , Humans , Hypoxia/prevention & control , Intraoperative Complications/epidemiology , Intraoperative Complications/prevention & control , Male , Middle Aged , Monitoring, Intraoperative , Myocardial Revascularization , Patient Selection , Postoperative Complications/epidemiology , Pulmonary ArterySubject(s)
Brain/pathology , Thiamine Deficiency/complications , Thiamine/administration & dosage , Thiamine/blood , Wernicke Encephalopathy/etiology , Wernicke Encephalopathy/pathology , Biomarkers , Brain/metabolism , Brain/physiopathology , Confusion/etiology , Diagnosis, Differential , Fatal Outcome , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Nerve Fibers, Myelinated/pathology , Thiamine/analysis , Thiamine Deficiency/drug therapy , Treatment Failure , Wernicke Encephalopathy/bloodABSTRACT
The aim of the study was to assess plasma catecholamine levels in patients undergoing myocardial revascularization and relate them to pulsatile (P) and nonpulsatile (NP) normothermic cardiopulmonary bypass (CPB). Twenty-eight patients were randomly assigned to different CPB management: 15 patients were assigned to group 'P', 13 patients to group 'NP'. During normothermic extracorporeal circulation, group 'P' received pulsatile perfusion, while group 'NP' received nonpulsatile perfusion. Levels of epinephrine and norepinephrine were evaluated during the operation and in the intensive care unit (ICU), at seven time points. Haemodynamic assessment was performed at four time points in the same period. Demographic and surgical data were collected, and the postoperative course was analysed. Epinephrine levels were markedly increased during CPB in both groups, while norepinephrine increased more in group NP in comparison with group P. No significant difference was found in fluid administration, transfusion, drugs usage, or postoperative complications. Normothermic pulsatile CPB seems to achieve reduced levels of norepinephrine. A clinical beneficial effect of this finding was not demonstrated during the study.
