Catheter deadspace: a source of error during tonometry

The dependence of measured alveolar deadspace on anatomical deadspace volume.

BACKGROUND Changes in pulmonary deadspace are indicators of disease status (e.g. pulmonary embolus, acute respiratory distress syndrome) and they have prognostic usefulness in the intensive care unit. The components of pulmonary deadspace, the alveolar and anatomical deadspaces (VDalv and VDanat), are commonly considered to be independent (i.e. the addition of airway equipment should not alter ...

Goldmann and error correcting tonometry prisms compared to intracameral pressure

BACKGROUND Compare Goldmann applanation tonometer (GAT) prism and correcting applanation tonometry surface (CATS) prism to intracameral intraocular pressure (IOP), in vivo and in vitro. METHODS Pressure transducer intracameral IOP was measured on fifty-eight (58) eyes undergoing cataract surgery and the IOP was modulated manometrically to 10, 20, and 40 mmHg. Simultaneously, IOP was measured ...

Deadspace in Paediatric Anaesthetic Apparatus.

The effective apparatus deadspace of the Magill, Potter and Cape Town gas circuits has been investigated using a model system simulating 3and 8-year-old children. (1) The Cape Town system is more suitable for smaller children. (2) The Potter system is more suitable for larger children. (3) A generous fresh gas flow will decrease the deadspace of the Potter and the Cape Town systems. A flow of d...

Visual analogue scales: a source of error.

[Rebound tonometry in a clinical setting. Comparison with applanation tonometry].

PURPOSE Rebound tonometry has recently been modified for its use in humans. The purpose of our study was to determine the precision of the ICare(R) rebound tonometer (RBT) as compared with the Goldmann applanation tonometer (GAT). METHODS Patients were recruited from our Hospital's Glaucoma Unit. In each patient, intraocular pressure (IOP) was measured without anaesthesia using the RBT and te...