Mary is a 68 year old female who came to theatres for a diagnostic laparotomy. A laparotomy is an opening of the abdomen for surgical intervention (Merck 2007). This was to be performed as an initial examination could not definitively determine Mary’s diagnosis. It was believed after having an abdominal X ray that a possible bowel obstruction was present. Mary presented with other factors such as pains and cramps in the abdomen, and vomiting. Mary displayed symptoms of sepsis, Tachycardia, Unstable blood pressure, a lack of cardiac stability and she was obese. Due to Mary’s co morbidities it was decided that Mary would require an Intensive treatment unit (ITU) bed, level 2. With so many co morbidities a safe and effective way to monitor a patient while being anaesthetised is required. Mary may be anaesthetised for a long period of time and possibly a large quantity of blood loss, this is another indication for the use of an A line (Gwinnutt 2004).The world health organisation (WHO) (2006) state it is a basic human right that we be treated with respect and made to feel safe in our surroundings. To achieve this and give optimum care, to monitor Mary effectively it was decided that an A line would be inserted in theatre after Mary had been anaesthetised, but prior to the initial surgical incision. Direct Arterial Pressure Measurement (A line).
An A line is created when separate individual pieces of equipment are connected to created and A line. The A line can then measure direct arterial pressure constantly on a “beat to beat” cycle, this aids a safe, efficient and precise management of ill patients (Pinnock et al 2003). This method of monitoring allows the anaesthetist a method for early intervention with drugs if required. This method of determining blood pressures is known as the “gold standard” of measurements. With an A line in situ, constant monitoring shows a real time reading of a patient’s arterial blood pressure, systolic, diastolic and mean in an electrical waveform (Pinnock et al 2003). Mean arterial pressure is often abbreviated to MAP this will be seen often in a theatre setting (Rushman et al 2000). With a constant visual display of MAP, systolic and diastolic pressures, this allows the anaesthetist to be able to detect abnormalities within the pressure and restore them to normal (the patient’s normal) (Carrie et al 200). The A line will also facilitate safe and least traumatic method for obtaining arterial blood samples, that can then be analysed in a blood gas analyser (Gwinnutt 2004).. This will provide the anaesthetist with an accurate display of pH levels of the blood, oxygen and bicarbonate levels also lactate and haemoglobin and electrolyte levels.
Advantages of direct arterial blood pressure;
Continuous measurement gives immediate warning of important changes in blood pressure. Shape of arterial waveform gives information relating to myocardial contractility and other haemodynamic variables. Facility for frequent arterial blood sampling.
Complex to perform.
Potentially inaccurate if apparatus is not set up correctly. Haematoma at puncture site.
Infection at puncture site, bacteraemia/septicaemia.
The insertion of an A line should be done using an aseptic technique (Darovic 2002). Prior to the insertion of the arterial cannulae, the Allen's test should be employed to ensure adequacy of the ulnar and radial arteries...