Dehydration Flashcards
Definition of Dehydration vs. Hypovolemia
Dehydration: loss of water without sodium or potassium -> in the absence of volume repletion may lead to hypernatremia
Hypovolemia: loss of isotonic fluid leading to a reduction of plasma volume
5 symptoms in adult
Fatigue, weakness, malaise, thirst, postural dizziness
Altered mental status, lethargy
Oliguria
Increased thirst
5 signs in adult
Orthostatic vitals (HR↑ >30bpm, sBP ↓> 20 or dBP ↓> 10mmHg) Tachycardia, tachypnea Dry mucosa Diminished skin turgor Sunken eyes Skin turgor Capillary refill >3s
Clinical Features of Hypovolemic Shock
hypotension, tachycardia, peripheral vasoconstriction, oliguria, AMS
Clinical Features of Pediatric Hypovolemia
Increased Thirst Restless Irritability Lethargy Loss of consciousness Sunken eyes fontanelle Absence of tears Weight Loss Fewer wet diapers
% volume / weight loss in mild, moderate and severe hypovolemia
Mild dehydration – 3-5% weight loss
Moderate dehydration – 6-9% weight loss
Severe dehydration - >9% weight loss
5 risk factors
fever vomit diarrhea Decreased Cognitive Function Reduced Oral Intake Absence or altered thirst mechanism Diuretics
Dehydration Risk Screening Tool: DEHYDRATIONS
D: diuretics E: end of life H: high fever Y: yellow urine turned dark D: dizziness (orthostatics) R: reduced oral intake A: axilla dry T: tachycardia I: incontinence O: oral problems N: neurologic impairment S: sunken eyes LR 3.7 **Dry mucus membranes LR 3.1** **Abnormal skin turgor LR 3.5**
Measurements / Physical Exam features of adult
BP – Hotn
HR – tachycardia
RR – tachypnea
Orthostatics: Pulse increased by 30, SBP increase by 20, DBP increase by 10
Volume status – less reliable in elderly:
Dry axilla LR 2.8
Moist mucus membrane / tongue WITHOUT furrow LR -0.3
Cap refill
Skin turgor
Clinical features of mild pediatric
Physical Exam findings normal
Clinical features of moderate pediatric
Tachycardia normal – low SBP \+/- tachypnea dry buccal mucosa sunken anterior fontanelle reduced skin turgor cool skin reduced urine output irritable
Clinical features of severe pediatric
Rapid / Weak / absent pulse Low SBP Tachypnea or decreased / absent breath Parched buccal mucosa Markedly sunken fontanelle Markedly sunken eyes Tenting of skin Skin cool, mottles, acrocyanotic Anuria Grunting / lethargy / coma
What serum and urine measurements?
Elevated Cr Elevated hematocrit Acid Base disturbance Electrolyte Abnormalities Elevated LFTs and Troponins Low Urine Na
What additional imaging?
POCUS: IVC <1cm diameter and obvious collapse
Fluid management of mild - moderate
Oral rehydration if the best option for both peds and adults
Indications for IV fluids
Severe Dehydration: Inability to tolerate PO intake Inability to administer ORT Persistent vomiting Electrolyte abnormalities where ORT cannot be monitored
Fluid resuscitation of the unstable adult (what / how much)
1-2 x 500cc – 1 L bolus crystalloid
Fluid resuscitation of the unstable pediatric (what / how much)
1-2 x 20 cc / kg bolus crystalloid
Pediatric Maintenance Fluid: what and how much?
4:2:1 Rule (4 ml / kg for first 10 kg, 2 ml / kg for 2nd 10 kg, 1 ml / kg for each kg > 20)
0.9% NS with 5% dextrose
Consider 10-20 mEq of KCL per each L of fluid to avoid hypokalemia
Adult Maintenance Fluid: what / how much
80 cc / hr of ½ NS in 5% dextrose with 20 mlEq of KCL for each L fluid
4 etiology / treatment of the underlying cause
Meds -> stop or reduce
Hyperglycemia -> fluids / insulin per DKA / HHS pathway
Infection -> antipyretics and abx
Emesis -> anti-emetics and identification / treatment of underlying cause
5 risk factors for dehydration in pregnancy
gHTN / preeclampsia gDM Preterm birth Oligohydramnios LFBW
Objective measures to follow while rehydrating someone
BP Weight Serum glucose Sodium Urea Creatining Potassium GFR
