A national survey of the use of ultrasound locating devices for placing central venous catheters

Abstract

modifications, the system could prove to be the first practical design step to preventing accidental crossconnection of neuraxial and intravenous lines, thereby improving patient safety. There is a good correlation between the calculated effect site concentration and the depth of anaesthesia. Propofol is known to depress the cardiovascular system but the relationship between the effect site concentration and cardiovascular depression has not been extensively studied. A previous study by Kazama et al. showed that the maximal cardiovascular depression (using systolic blood pressure only) would happen some 8 min after peak plasma propofol concentrations [1]. We wished to investigate this further while using effect site concentration target-controlled infusions (TCI) of total intravenous anaesthesia (TIVA). MethodsLocal Research Ethics Committee approval was given and informed consent obtained from 20 patients of ASA physical status 1-2 due to undergo elective day surgery. They were then anaesthetised using a standard effect site concentration TIVA technique. From the time of attaining a steady state effect site concentration of both propofol and remifentanil ([ES] ss ) we measured Bispectral Index, heart rate, blood pressure and cardiac index every minute for 25 min. Any alterations were then mathematically modelled in a nonlinear regression model to calculate when they reached a steady plateau with 95% certainty. ResultsThese are shown in Table 1. DiscussionWe have shown that the time to maximal cardiovascular depression occurs well after that previously claimed [1]. The depression of cardiovascular parameters is most profound in the vasodilatation that is well known with propofol, reflected in the drop in mean arterial pressure. The reduction in heart rate is also significant but reflex mechanisms of increasing the stroke volume ensures that the measured cardiac index changes less. These results show that after achieving steady state concentrations of anaesthetic agents the cardiovascular system depresses further with a maximal time of depression 78 min after achieving calculated steady state anaesthesia. Papers using patients at 'steady state' anaesthesia must either have a comparable control arm to the experiment or wait for 78 min until the cardiovascular systems achieve a steady plateau.

Effect of the implementation of NICE guidelines for ultrasound guidance on the complication rates associated with central venous catheter placement in patients presenting for routine surgery in a tertiary referral centre

“…Other reasons advanced for the reluctance to take up US range from the relative paucity of studies involving anaesthetists to the lack of representation on the NICE committee of anaesthetic consultants. 22 The argument that US machines are not available no longer seems to hold water after the publication of a survey by Harris and colleagues 23 that showed 86% of departments had a US locating device.…”

A survey of the use of ultrasound guidance in internal jugular venous cannulation*

“…Although our survey did not determine a reason for this, a survey conducted by NICE, in 2005, found that of 250 consultant anaesthetists questioned, 67% had received poor or no training in the use of 2D ultrasound devices [7]. However, training in use of 2D ultrasound devices appears to be increasing and comes from a variety of sources ranging from the manufacturers of the devices to informal teaching from experienced colleagues [9]. Overall, 75% of respondents stated they would use ultrasound as a first, second or third choice leaving us with the assumption the majority are comfortable with the technique.…”

Ultrasound-Guided Regional Anaesthesia in the Paediatric Population

“…Recommendation for the use of ultrasound in the insertion of central lines in the NICE guidelines of 2002 [3] has resulted in an increase in the availability of portable ultrasound machines in the theatre environment. A study in 2007 found that 86% of departments had access to ultrasound [4].…”