Critical care medicine
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Critical care medicine · Aug 1993
Randomized Controlled Trial Comparative Study Clinical TrialIntraoperative and postoperative effects of vancomycin administration in cardiac surgery patients: a prospective, double-blind, randomized trial.
In response to an increased frequency of Staphylococcus epidermidis infections in postoperative cardiac surgery patients, antibiotic prophylaxis was changed to include both vancomycin and cefazolin pre- and intraoperatively. Subsequent to the addition of vancomycin prophylaxis, clinical impression and retrospective analysis supported a correlation between vancomycin administration and post-cardiopulmonary bypass norepinephrine use. ⋯ The results show that a significantly greater number of patients who received vancomycin required a norepinephrine infusion and that, despite norepinephrine infusion therapy, systemic vascular resistance was not normalized in this group of patients. The study supports the conclusion that perioperative administration of vancomycin in cardiac surgery patients may result in hypotension requiring the use of a vasopressor in an attempt to normalize hemodynamic indices.
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Critical care medicine · Aug 1993
Changes in myocardial blood flow rates during hyperdynamic sepsis with induced changes in arterial perfusing pressures and metabolic need.
To determine whether hyperdynamic sepsis is associated with dysregulation in the control of myocardial blood flow rates unrelated to hypotension or the use of anesthetic agents. ⋯ In this model of hyperdynamic sepsis, increases in blood flow to both the left and right ventricles were positively coupled to changes in respective ventricular work. From the interventional PGE1 and zymosan-activated plasma infusion studies, we found no evidence to support previous suggestions that the regulation of myocardial blood flow rates according to changes in perfusing pressure and/or metabolic oxygen need is significantly altered during hyperdynamic sepsis.
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Critical care medicine · Aug 1993
Randomized Controlled Trial Multicenter Study Comparative Study Clinical TrialAccurate placement of central venous catheters: a prospective, randomized, multicenter trial.
a) To define the frequency of dangerous (intracardiac) central venous catheter placement in a multicenter study of large community hospital intensive care units (ICUs) and to evaluate physician responses to this finding. b) To validate right atrial electrocardiography as a technique to assure adherence with recent Food and Drug Administration (FDA) guidelines regarding the location of central venous catheter tips. c) To conduct a literature review of vascular cannulation and its associated potentially lethal complications. ⋯ a) The FDA guidelines regarding catheter tip location (catheter tip should not be in the right atrium) have not been widely publicized. b) The average safe insertion depth for a central venous catheter from the left or right internal jugular vein or subclavian vein is 16.5 cm for the majority of adult patients; a central venous catheter should not be routinely inserted to a depth of > 20 cm. Catheters longer than this size are rarely needed, and potentially dangerous. Catheter tip location is important to document following central venous catheter insertion. Thirty-centimeter central venous catheters should not be used when accessing the central circulation via internal jugular or subclavian veins. c) Right atrial electrocardiography is a technique that assures initial tip position outside the heart in accordance with FDA guidelines. This technique would virtually eliminate the major risk of death (i.e., cardiac perforation) associated with this procedure. d) Recently available, 15- and 16-cm central venous catheters have significant potential to minimize intracardiac placement of central venous catheters by either the internal jugular or subclavian vein route and may become the standard of care.
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Critical care medicine · Aug 1993
Randomized Controlled Trial Comparative Study Clinical TrialThoracic electrical bioimpedance measurement of cardiac output in postaortocoronary bypass patients.
To assess the degree of correlation and agreement between cardiac output by thermodilution and bioimpedance using the BoMed NCCOM3-R7 monitor in postaortocoronary bypass patients. ⋯ Use of the BoMed NCCOM3-R7 bioimpedance monitor as a replacement for thermodilution-derived cardiac output cannot be recommended in postaortocoronary bypass patients. The distortions of patients' normal anatomy and physiology, coupled with the presence of endotracheal tubes and mechanical ventilation, mediastinal tubes and chest tubes, result in only fair correlation, significant bias, and poor precision between the two measures of cardiac output.
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Critical care medicine · Aug 1993
Active core rewarming in neurologic, hypothermic patients: effects on oxygen-related variables.
To determine in hypothermic patients if a) the decrease in oxygen consumption (VO2) is exclusively dependent on the decrease in metabolic rate, or b) as a consequence of the greater hemoglobin affinity for oxygen, hypothermic tissues have impaired oxygen extraction. ⋯ These data show that VO2 was reduced to half of normal values during hypothermia. Active core rewarming produced an average 4.5% increase in VO2 per 1 degree C that was characterized by the wide variation observed in this metabolic response between different patients and for individual cases. Despite the rightward shift of P50 observed during rewarming (mainly due to the Bohr effect), no change was reflected on the oxygen extraction ratio.