Blood pressure : non-invasive method to monitor drug action

Abstract

This pilot study investigated whether the daily measurement of a noninvasive parameter such as blood pressure using a mercury sphygmomanometer monitors drug action and interaction. The blood pressure of six patients aged 68 to 87 years (one male and five females) treated with cardiovascular drugs was monitored for up to forty one days together with changes in the treatment or patients' condition. Some patients have periods of larger variations in the blood pressure than others and are probably related to episodes of increased worry due to a worsening condition such as pain. The establishment of a baseline profile of the blood pressure helps to detect trends of changes in blood pressure. The sudden increase of the diastolic blood pressure to lOOmmHg followed by a drop to 6SmmHg over a five day period preceded a fall, 9izziness and postural hypotension. Withdrawal of the di uretic brought an improvement while the blood pressure returned to pre-crisis values. In another case, diuretic withdrawal caused no deterioration of the blood pressure. Blood pressure monitoring indicated that drugs could be safely withdrawn from a polypharmacy treatment. In one case the blood pressure was controlled by increasing the dose of nifedipine and withdrawing the diuretic and atenolol. In an 82 year old the withdrawal of cimetidine which was combined with nifedipine brought no change in the blood pressure, an interaction expected in younger subjects. The graphical representation of the observations should promote a more rational drug use and trigger the sequence for investigations at the right time.