Utilization of electron beam CT scan in diagnosis of pulmonary embolism.

Pulmonary embolism is a difficult entity to diagnose clinically and pulmonary angiogram has been the gold standard for the diagnosis. Our objective was to evaluate the usefulness of electron beam (Ultrafast) CT scan in aiding the diagnosis of such an entity, thus avoiding an invasive procedure. Between April 1995 and March 1996 we prospectively studied 20 patients with clinical suspicion of pulmonary embolism by conventional perfusion scan of the lung, by invasive pulmonary angiography and by contrast enhanced electron beam CT scan. Simple statistic correlation between the 3 methods was obtained in regard to sensitivity and specificity utilizing the pulmonary angiogram as the gold standard. The sensitivity and specificity of contrast enhanced electron beam CT scanning was 95 per cent and 100 per cent respectively. The correlation of positive and negative result of all three imaging modalities was 60 per cent. Contrast enhanced electron beam (Ultrafast) CT scan is a good alternative diagnostic modality for pulmonary embolism.

Improvement of inhaler efficacy by home-made spacer.

The delivery of aerosol from a metered dose inhaler (MDI) was reported to be more efficient with a spacer. Hence, a home-made spacer modified from a 950 ml low cost plastic bottle, was compared with a MDI and with a 750 ml imported spacer (Nebuhaler). On three consecutive days, at the same time of day, 20 adult patients with chronic asthma inhaled two puffs of terbutaline sulphate (0.5 mg), delivered from MDI alone, MDI with a 750 ml Nebuhlaer and MDI with a home-made spacer. The following measurements were made: forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and pulse rate. These measurements were carried out immediately before and at 5, 20, 60 min after inhalation of terbutaline. FEV1 was significantly increased (P < 0.05) at 5, 20 and 60 min after administration of terbutaline with MDI via either spacers than with MDI alone but no significant difference was observed between Nebuhaler and the home-made spacer. FVC and pulse rate showed no significant change with each method of administration. In conclusion, terbutaline delivered by MDI and home-made spacer was more effective in bronchodilatation than by MDI alone and was just as effective as MDI and Nebuhaler. The home-made spacer therefore offers a simple, inexpensive and more effective method for delivering aerosol drug.