This is a great example of a randomised controlled trial, where there are three groups with the same condition being measured in the same way. The physiological parameters (blood pressure, heart rate etc) were not significantly different between the three groups however. The group where patients had foot holding demonstrates that placebo effects were not responsible for the changes, and appears to support the notion that reflexology over heart and lung foot reflex areas had a more beneficial effect. The results suggest that pain relief and relief of anxiety allowed the patients to reduce their reliance on ventilation sooner.
Here'e the reference for those who want to read the paper :
Abbas Ebadi, Parastoo Kavei, Seyyed Tayyeb Moradian, Yaser Saeid "The effect of foot reflexology on physiologic parameters and mechanical ventilation weaning time in patients undergoing open-heart surgery: A clinical trial study"; Complementary Therapies in Clinical Practice 21 (2015) 188-192