A report published in Anesthesia & Analgesia, the official journal of the International Anesthesia Research Society (IARS) talks about the spectrophotometric haemoglobin sensor (SpHb), which gives a new face to the non-invasive monitoring of haemoglobin levels during surgery.
Dr. Ronald D. Miller of the University of California has authored the report. With further research and development, the sensor can be made suitable for giving accurate results in non-invasive blood monitoring and also reduce the need for transfusion of blood that may arise during surgery.
The SpHb was used to monitor haemoglobin levels of 20 patients who were administered general anaesthesia during spinal surgery. The SpHb provides more details on different variables in blood, which includes haemoglobin when compared to the “finger clip” pulse oximeter. For major surgeries, the decision to transfuse blood is taken based on the haemoglobin levels that are measured at regular intervals.
The measurements taken by SpHb were compared in as many as 78 ways with the measurements taken by standard invasive procedures and using HemoCue based on different cut off points for transfusion decisions. The SpHb gave reasonably accurate results in the comparison study. However, the difference in haemoglobin levels for 61% of cases was less than 1.5 g/dL, but in 22% cases it was more than 2 g/dL. The study concluded that the sensor proved to be more accurate in case of surgeries lasting for longer time and also in cases where the tissue blood perfusion level was high. The measurements taken by HemoCue proved to be more in line with the standard measurements.
The report further went on to say the non-invasive method of haemoglobin monitoring is a plus for SpHb. However, only after more fine tuning and modifications can SpHb be suitable for vital clinical applications. Nevertheless, the current design of the SpHb it could be used to direct the timing of direct measurement of haemoglobin in the samples.