To control or to be controlled? From health locus of control to morphine control during patient-controlled analgesia.

We postulated that patients with an internal locus of control, i.e. those who like to control their health problems themselves, would adapt more adequately to the 'patient-controlled analgesia' technique as compared to patients with an external health locus of control, who do not believe in their own control. Since contradicting studies have been published on this matter, we investigated relations between the demand for analgesics, perceived pain in the postoperative phase, and the health locus of control in the postoperative context of cardiac surgery. Findings demonstrate distinct utilization patterns between subjects with internal or external locus of control concerning total morphine consumption, number of unsatisfied demands and reduction of perceived pain.