Cellular Environment 2023.pdf

By Steve Casarez RN, MICN, Paramedic Update 2023 ▪ Needs a functioning system to distribute nutrients to the right place so it can carry out its duties and functions.  Intracellular (ICF) Fluid inside the cell  Extracellular (ECF) Fluid outside the cell. There are two types: 1. Intr...

By Steve Casarez RN, MICN, Paramedic Update 2023 ▪ Needs a functioning system to distribute nutrients to the right place so it can carry out its duties and functions.  Intracellular (ICF) Fluid inside the cell  Extracellular (ECF) Fluid outside the cell. There are two types: 1. Intravascular Fluid in arteries and veins carrying plasma, blood products, and nutrients. 2. Interstitial Fluid or 3rd Space commonly seen as Edema  Both ICF and ECF should have the same concentration or (Osmolarity).  Permeable Membranes are: ▪ A delicate membrane that separates the two and allows fluid to move in and out. Extracellular Fluid Intravascular Interstitial Intracellular Fluid Note: Elderly patients' total body% of water drops too around 45-40% estimated TOTAL The body moves fluid and nutrients in three ways, and diseases and trauma can alter these normal processes: 1. Osmosis 2. Diffusion 3. Mediated Transport Insensible Fluid Loss (approx. 1,600 mL in 24 hours)  From the skin  Respiratory tract  Urine output  Sweating (approx. 100mL)  Fecal loss (approx. 200mL) Replacement comes from three primary sources  Oral intake of fluids like water, commonly called hydration  Metabolic water production from oxidation of food  And with medical interventions of intravenous (IV) fluids   Both are Solute Concentrations  Is the number of active particles in a kilogram or liter of water  Salt (Sodium) is the most abundant in ECF  NA+ = 135 – 145 mEq/ dL  Serum Osmolality  Serum Osmo 280 – 295 mEq/ dL FUN FACT: Why do we call 0.9% sodium chloride Normal Saline? It is because of Osmolality! 0.9% sodium chloride is 308 Circulating blood is 275-299 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4794509/ 1st is Osmosis Defines the movement of water between ICF / ECF that moves from Hypo to Hyper solutes  Isotonic ▪ Equal balance concentration between ICF / ECF  Hypertonic ▪ Higher concentration in ECF than in ICF ▪ Example: seawater  Hypotonic ▪ Lower concentration in ICF than in ECF ▪ Example: distilled water ▪ Water moves from lower solute concentration to a higher solute concentration Equal balance concentration between ICF / ECF  Blood has approx. 290-300 mOsm/L  Equal solutes  Common Isotonic IV Fluids  0.9% Sodium Chloride  Lactated Ringers  D5W (5% dextrose in water) as free water ONLY  Treatment Goals  Hydration  Increase Preload in Shock  Hypoglycemia  Hypertonic  More solutes outside the cell  Pulls fluid from IC to EC  Common Hypertonic IV fluids  D5NS  D5LR  D5 0.45%  10% Dextrose  3.0% Sodium Chloride  TX Goals  Pull excess fluid off to treat edema  Used in TBI when herniation is present Hypotonic  More solutes in the cell  Pulls fluid from EC to IC  Common Hypotonic IV fluids ▪ D5W (5% dextrose in water) when dextrose is metabolized ▪ 0.25% sodium chloride ▪ 0.45% sodium chloride ▪ 0.225% sodium chloride  TX Goals ▪ Aggressive Cellular hydration ▪ Pulls fluid from the vascular system into the ICF 2nd is the Diffusion of Solids and Gases  Spreading of molecules from a higher concentration to a lower concentration  Bodies’ way to keep equilibrium by keeping the concentration gradient equal as possible  Example of locations: Lungs and Kidneys Diffusion of Gases Diffusion of Solids ▪ Measures Expired Carbon Dioxide (Co2) ▪ Co2 is a byproduct of cellular respiration ▪ eTCO2 can assess patient status for: ▪ Metabolic Status ▪ Adequate Circulation ▪ Adequate Ventilation ▪ Perfusion emergencies ▪ All four are independent of one another depending on your goals and outcomes for the patient ▪ THIS IS NOT USED FOR CHECKING OR MONITORING OXYGENATION  Moving solutes against a concentration gradient  From lower to higher concentration 1st Active Transport 2nd Facilitated Diffusion Active transport  Faster then diffusion  Uses A GREAT DEAL of energy  Example: ▪Sodium/ Potassium pump ▪ATP production Facilitated Diffusion  Uses a helper protein to move against the concentration  Example: Insulin helps glucose into the cell  Arterial Venous High Pressure side Low Pressure side A-line Pressures Cuff Blood Pressure Hydrostatic pressure Hydrostatic pressure 35mmHg 17mmHg Interstitial space Oncotic pressure Oncotic pressure 25mmHg 25mmHg Membrane Capillary bed 1. This movement is related to pressures ▪ Hydrostatic pressures ▪ Pressure to the walls of the vessels ▪ Forces fluids out of capillaries ▪ Osmotic pressures Hemodynamics ▪ Pulls fluid into the capillaries 2. Intravascular ▪ has high pressures 3. Interstitial ▪ has lower pressures  Pressure exerted by a fluid because of its weight  Weight will be based on the pressure exerted by the pump and by the diameter of the pipe onto the capillary  Arterial Hydrostatic pressures 40 mmhg  Venous Hydrostatic pressures 10 mmhg  Example of this is Blood Pressures Mean Arterial Pressure (MAP) normal at 60-120 mmHg. MAP measures end-organ perfusion pressures.  Dependent on Cardiac Output (CO=HRxSV)  Dependent on Right Ventricular Filling  Dependent on Systemic Vascular Resistance (SVR) or the radius of the blood vessels. Dilation Constriction Normal Tone  Dilation Constriction The Patient : = Low Blood Pressure The Patient: = Low Cardiac Output = High Blood Pressure = Low Mean Arterial Pressures = High Cardiac Output = Low Systemic Vascular Resistance = High Mean Arterial Pressures Causes: = High Systemic Vascular Resistance = Loss of vagal tone Causes: = Distributive Shock = Early stages of Shock = Septic Shock = Compensated Shock = Decompensated Shock = Overdose of blood pressure medications  What are some other injuries and diseases that may change blood pressure or hydrostatic pressures?  Pressure difference between a semipermeable membrane, through which it cannot penetrate  Pressures related to the concentration of colloids in the fluid  Example: capillary pressures or Cap refill time  Edema may be a result of these changes  Tonicity  Is the minimum pressure needed to prevent inward flow across a semipermeable membrane  Alteration in this permeability increases the space for exchange: ▪ Sepsis ▪ Bacterial Infections ▪ Shock ▪ Pneumonia Edema  Collection of water in the interstitial space  3rd spacing  Causes ▪ Increased Capillary hydrostatic pressure ▪ Decreased Plasma Oncotic pressure (intravascular) ▪ Increased capillary membrane permeability ▪ Histamine Response ▪ Damage to cells make them “leaky” ▪ Lymphatic obstruction Increased hydrostatic pressure  Occlusion or Diminish of Venous flow  Retention of salt and water  Common Causes ▪ CHF ▪ End Stage Renal Disease Decreased Plasma Osmotic Pressures  Reduced plasma proteins  Not enough pressure to pull fluid through the interstitial space  Common Causes ▪ Liver disease ▪ Resuscitation ▪ Hemorrhagic Increased capillary membrane permeability  Inflammation and Immune response  Histamine response  “Leaky” cells  Common Causes ▪ Trauma ▪ Burns ▪ Crushing injuries Lymphatic obstruction  Lymphedema  Blocked or impaired lymphatic system  Common Causes ▪ Mastectomy Localized edema can be deadly  Cerebral edema  Has no space to move the fluids  Result is increase in ICP and herniation  EMS S/S ▪ Acute decrease in GCS ▪ Cushing's Triad ▪ Unequal or Nonreactive pupils Localized edema can be deadly Compartment Syndrome  Increase edema in a compartment  Decrease blood flow distal to the injury  Sensory damage  EMS S/S the 5 P’s ▪ Pain out of proportion to findings ▪ Paresthesia (pins and needles) ▪ Paralysis ▪ Pallor (pale) ▪ Pressure Dependant Edema  Pitting edema  Is measurable  Common areas ▪ Feet / lower extremities ▪ Presacral edema  High pressure Hydrostatic Cell Oncotic Low pressure