Questions regarding Dialysis study

1. How is "sudden drop of blood pressure" defined?

2. Does the sequence of administration of dialysate at different temperatures have confounding effects? In other words, if a patient is assigned to the "cold" group, will (s)he be more/less likely to develop hypotension during the subsequent "hot" period compared with someone who is given warm dialysate at the beginning?

3. From the sample data it seems that all patients were monitored from late May to early August. Depending on the location of the study, the ambient temperature may change significantly during that period, and as such "room temperature" could be quite variable throughout the study if it is not kept more or less constant.