Boxplots of body temperatures. Figure 2 contains six boxplots for 11 patients who received endovascular cooling. On the x-axis and for each boxplot, the number corresponds to the differents steps; the y-axis shows body temperatures. The shaded box denotes the middle 50% of the data, and hence the lower and upper ends of the box denote the 25th and 75th percentiles, respectively. The solid black horizontal line through each shaded box denotes the median of the distribution and the black cross denotes the mean. The vertical solid black lines ('whiskers') reach out to 1.5× the interquartile range. Circles above the whiskers denote individual extreme observations. Step 0: temperature before infusion of 2 l of NaCl 0.9% at 4°C; step 1: temperature at the end of perfusion; step 2: initial temperature in emergency room; step 3: initial temperature in ICU; step 4: temperature after 30 minutes of endovascular cooling (Coolgard 3000™); and step 5: temperatures after 12 hours of endovascular cooling (Coolgard 3000™). *P < 0.05.