Der Anaesthesist
-
The term blood volume (BV) measurement can be understood as the exact volumetric definition of both components of blood, the red cell volume (RCV) and the plasma volume (PV) using tracer dilution methods. The tracer used to measure the RCV must be bound to the erythrocytes and for the PV to plasma proteins, in order to label the distribution space of each carrier (i.e. erythrocytes and albumin molecules). To differentiate this there are indirect methods to estimate the BV, such as measurement of the diastolic pressure or transoesophageal echocardiography, which will not be discussed here. ⋯ However, the results of the RCV measurement can only be delivered after 1 h which makes it more suitable for clinically stable situations. In contrast the PV estimation is based on the measurement of the ICG concentration in the arterial bloodstream after a bolus injection of the dye in the central veins and is used more in intensive care because of the invasivity. The results can be obtained 5 min after injection of the dye and therefore even rapid changes in the PV can be monitored.
-
What is the impact of acute preoperative normovolemic hemodilution (ANH) on blood volume, intravascular colloid, and loss of red cells in the perioperative period? ⋯ Double label measurements of blood volume demonstrated that with the colloids used a surplus of 15% of colloid infusion in relation to blood removal was necessary to generate isovolemia after ANH.
-
Case Reports
[Unilateral high-frequency jet ventilation supporting one-lung ventilation during thoracic surgical procedures].
We report two cases where surgery on the right lung had to be performed for resection of a malignoma. In both cases, function of the left lung was severely restricted. In the first patient, the volume on this side was reduced by around 50% as the result of a recently performed upper lobe resection. ⋯ Under this procedure arterial O2 saturation ranged from 96 to 100%, and arterial CO2 partial pressure was 45 mmHg. Surgery was not hindered by ventilation, the postoperative progress was also without complications. The case reports show that with the help of the ventilation regime described (operated side: HFJV, non-operated side: IPPV) lung surgery can be successfully performed on patients who are unsuitable for conventional one-lung ventilation for functional reasons.