General principles and patient assessment

The assessment of patient history, chief complaint, and physical exam findings will determine the need for additional testing and fluid therapy. Assess for the following three types of fluid disturbances:
  1. Changes in volume (e.g., dehydration, blood loss)
  2. Changes in content (e.g., hyperkalemia)
  3. Changes in distribution (e.g., pleural effusion)

The initial assessment includes evaluation of hydration, tissue perfusion, and fluid volume/loss. Items of particular importance in evaluating the need for fluids are described in Table 1. Next, develop a treatment plan by first determining the appropriate route of fluid administration. Guidelines for route of administration are shown in Table 2.

Consider the temperature of the fluids. Body temperature (warmed) fluids are useful for large volume resuscitation but provide limited usefulness at low IV infusion rates. It is not possible to provide sufficient heat via IV fluids at limited infusion rates to either meet or exceed heat losses elsewhere.1


Evaluation and monitoring parameters that may be used for patients receiving fluid therapy

  • Pulse rate and quality
  • Capillary refill time
  • Mucous membrane color
  • Respiratory rate and effort
  • Lung sounds
  • Skin turgor
  • Body weight
  • Urine output
  • Mental status
  • Extremity temperature
  • Packed cell volume/total solids
  • Total protein
  • Serum lactate
  • Urine specific gravity
  • Blood urea nitrogen
  • Creatinine
  • Electrolytes
  • BP
  • Venous or arterial blood gases
  • O2 saturation


Determining the route of fluid administration

Patient parameter Route of fluid administration
Gastrointestinal tract is functional and no contraindications exist (e.g., vomiting) Per os
Anticipated dehydration or mild fluid volume disturbances in an outpatient setting Subcutaneous. Caution: use isotonic crystalloids only. Do not use dextrose, hypotonic (i.e., D5W), or hypertonic solutions. Subcutaneous fluids are best used to prevent losses and are not adequate for replacement therapy in anything other than very mild dehydration
Hospitalized patients not eating or drinking normally, anesthetized patients, patients who need rapid and/or large volume fluid administration (e.g., to treat dehydration, shock, hyperthermia, or hypotension) IV or intraosseous
Critical care setting. Used in patients with a need for rapid and/or large volume fluid administration, administration of hypertonic fluids and/or monitoring of central venous pressure Central IV

D5W, 5% dextrose in water.