This slide summarizes the simplest ways to diagnose dehydration. Ask the patient (or his mother) about the frequency and consistency of his stools, whether he is vomiting, and if he is thirsty. When was urine last passed? Was the volume changed from normal? Look at the patient: his general appearance, his eyes, and the appearance of the mucous membranes, lips and tongue. Observe the pattern of respiration, the thoracic cage, and the nostrils. Feel the skin, note its texture, its turgor; pinch folds of skin over the abdomen or at the back of the neck to test for "tenting". Feel the pulse, note how fast it is and how strong. In infants, inspect and feel the fontanelle. If a weighing machine is available, and the child has been routinely weighed, determine the percentage of body weight loss. If possible, measure also the patient's blood pressure.