ESWL-induced acute kidney injury is dose-dependent (increases with the total number of shock waves administered and with the power setting of the lithotriptor) and can be severe, including internal bleeding and subcapsular hematomas. On rare occasions, such cases may require blood transfusion and even lead to acute kidney failure. Hematoma rates may be related to the type of lithotriptor used; hematoma rates of less than 1% and up to 13% have been reported for different lithotriptor machines. Recent studies show reduced acute tissue injury when the treatment protocol includes a brief pause following the initiation of treatment, and both improved stone breakage and a reduction in injury when ESWL is carried out at slow shock wave rate.In addition to the aforementioned potential for acute kidney injury, animal studies suggest these acute injuries may progress to scar formation, resulting in loss of functional renal volume. Recent prospective studies also indicate elderly people are at increased risk of developing new-onset hypertension following ESWL. In addition, a retrospective case-control study published by researchers from the Mayo Clinic in 2006 has found an increased risk of developing diabetes mellitus and hypertension in people who had undergone ESWL, compared with age and gender-matched people who had undergone nonsurgical treatment.
Sadness is an emotional pain associated with, or characterized by, feelings of disadvantage, loss, despair, grief, helplessness, disappointment and sorrow. An individual experiencing sadness may become quiet or lethargic, and withdraw themselves from others. An example of severe sadness is depression, a mood which can be brought on by major depressive disorder or persistent depressive disorder. Crying can be an indication of sadness.Sadness is one of the six basic emotions described by Paul Ekman, along with happiness, anger, surprise, fear, and disgust. : 271–4

Childhood
Sadness is a common experience in childhood. Sometimes, sadness can lead to depression. Some families may have a (conscious or unconscious) rule that sadness is "not allowed", but Robin Skynner has suggested that this may cause problems, arguing that with sadness "screened off", people can become shallow and manic. : 33, 36  Pediatrician T. Berry Brazelton suggests that acknowledging sadness can make it easier for families to address more serious emotional problems. : 46, 48 Sadness is part of the normal process of the child separating from an early symbiosis with the mother and becoming more independent. Every time a child separates a little more, he or she will have to cope with a small loss. If the mother cannot allow the minor distress involved, the child may never learn how to deal with sadness by themselves.