[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Clinical exam](https://durgical.com/en/clinical-exam/) › [General exam and vital signs](https://durgical.com/en/clinical-exam/#a-general) › Hydration status: signs of dehydration [Clinical exam](https://durgical.com/en/clinical-exam/) · [General exam and vital signs](https://durgical.com/en/clinical-exam/#a-general) # Hydration status: signs of dehydration - Exam technique What to look at and feel at the bedside to tell whether a patient is short of fluid, and by how much. Updated 2026-11-01 **See it in 3D:** [Tongue](https://durgical.com/en/anatomy/tongue/) · [Skin](https://durgical.com/en/anatomy/skin/) ## Key points - Mild (3 to 5% weight loss in children): slightly dry mucosae and slightly less urine; normal pulse and pressure. - Moderate (6 to 8%): dry mucosae, sunken eyes and fontanelle, reduced skin turgor, tachycardia, little urine, lethargy. - Severe (10% or more): no tears, prolonged capillary refill, fast weak pulse, hypotension, mottled skin, coma. - In older adults thirst and skin turgor are unreliable; an orthostatic fall in pressure and confusion help more. - Urine output is key for nursing: record intake and output and daily weight. ## What it is Hydration assessment looks for signs of volume loss: thirst, dry mucosae, sunken eyes, slow skin recoil, slow capillary refill, tachycardia, hypotension and less urine. In children, dehydration from diarrhea is still a major reason for consultation in Colombia and is graded by severity. No single sign is enough; a combination is more accurate. ## Landmark anatomy - Oral mucosa is judged on the inside of the cheeks and on the tongue. - In infants, the anterior fontanelle lies between the frontal and parietal bones. - Skin turgor reflects dermal elasticity, which falls with dehydration and with age. ## Technique, step by step - Ask about vomiting, diarrhea, fever, intake, thirst, how often and what colour the urine is, and diuretic use. - Observe general state: alert, irritable, lethargic or unconscious. - Inspect the oral mucosa and tongue, the presence of tears and whether the eyes look sunken. - In infants, feel the anterior fontanelle with the child calm and held upright. - Pinch the skin of the abdomen or back of the hand and see how long it takes to fall back. - Check capillary refill, pulse, blood pressure and, if possible, orthostatic signs. - Weigh the patient and compare with a recent weight; record urine output. ## Abnormal findings - Dehydration from acute gastroenteritis, especially in young children. - Losses from fever, sweating or heat stroke; extensive burns. - Polyuria from uncontrolled diabetes or diuretics. - Poor intake in older adults and in patients with dementia or dysphagia. - Severe signs with altered consciousness or a weak pulse: hypovolemic shock. ## Common errors - Relying on a single sign, such as a dry mouth in a mouth-breather. - Interpreting skin turgor in an older adult, whose skin loses elasticity with age. - Judging the fontanelle while the infant is crying or lying down. - Not weighing the patient or recording urine output. ## Test yourself Think of the answer, then tap the question to see it. ## Which signs separate severe from moderate dehydration in a child? Absent tears, prolonged capillary refill, a fast weak pulse, hypotension, mottled skin and severely reduced consciousness. ## Why is skin turgor unreliable in older adults? Because skin loses elasticity with age and the fold returns slowly even when the person is well hydrated. ## How is the anterior fontanelle correctly assessed? With the infant calm, not crying and held upright; a sunken fontanelle suggests dehydration. ## What percentage of weight loss corresponds to mild dehydration in a child? About 3 to 5% of body weight. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/clinical-exam/hydration-status-signs-of-dehydration/) ## See it in 3D The structures of Durgical's 3D anatomy where it is found. - [Tongue](https://durgical.com/en/anatomy/tongue/) - [Skin](https://durgical.com/en/anatomy/skin/) ## Related - [Capillary refill time](https://durgical.com/en/clinical-exam/capillary-refill-time/) - [Orthostatic vital signs](https://durgical.com/en/clinical-exam/orthostatic-vital-signs/) - [Dehydration and fluid overload](https://durgical.com/en/clinical-exam/dehydration-and-fluid-overload/) - [Vital signs in children: how they change with age](https://durgical.com/en/clinical-exam/vital-signs-in-children-how-they-change-with-age/) ## Related conditions - [Dehydration (fluid volume deficit)](https://durgical.com/en/conditions/dehydration/) - [Dehydration in children (acute diarrhoeal disease)](https://durgical.com/en/conditions/dehydration-in-children/) - [Hypovolaemic shock](https://durgical.com/en/conditions/hypovolaemic-shock/) [← All of the clinical exam](https://durgical.com/en/clinical-exam/) Educational content on the clinical exam; it is learned and practised under supervision. It does not replace assessment by a health professional and is not for self-diagnosis. Sources: [Dehydration: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/000982.htm) (U.S. National Library of Medicine (MedlinePlus), 2025); [Dehydration in Children - Pediatrics - MSD Manual Professional Edition](https://www.msdmanuals.com/professional/pediatrics/dehydration-and-fluid-therapy-in-children/dehydration-in-children) (Merck & Co. (MSD Manual Professional Edition), 2025). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/clinical-exam/hydration-status-signs-of-dehydration/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/clinical-exam/hydration-status-signs-of-dehydration/