Changes in forearm blood flow during single and intermittent cold application.

STUDY DESIGN Two-factor repeated measures design. OBJECTIVES To compare the effects of a 20-minute cold application to the effects of a 20-minute cold application followed by 20 additional minutes of intermittent cold on forearm blood flow over a 60-minute period. BACKGROUND The appropriate duration of cold application as a therapeutic modality following soft tissue trauma is an important clinical question because the goal of using this modality is to limit edema, decrease pain, and produce effective muscle relaxation without causing cold-induced reactive vasodilatation or nerve damage. METHODS AND MEASURES Thirteen subjects (mean age, 21.46 +/- 4.01 years) volunteered to participate in this study. A bilateral tetrapolar impedance plethysmograph was used with venous occlusion to measure changes in local limb blood volume at the forearm for a period of 60 minutes under 2 conditions: Condition 1: Prolonged intermittent cold application (20 minutes ice application; 10 minutes off; 10 minutes ice on; 10 minutes off; 10 minutes ice on); Condition 2: Cold followed by application of a room-temperature pack of equal weight to the ice bag (20-minute ice application; 10 minutes off; 10 minute room-temperature pack on; 10 minutes off; 10-minute room-temperature pack on). RESULTS A significantly lower blood flow was noted during the last 10 minutes of Condition 1 compared with Condition 2. CONCLUSIONS The findings of this study indicate that blood flow is reduced when a prolonged intermittent cold application (Condition 1) is used compared to a single cold application (Condition 2).