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Paramedic Care: Principles & Practice Volume 4 Trauma Emergencies Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Chapter 4 Hemorrhage and Shock Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Topics Introduction to Hemorrhage and Shock Hemorrhage Shock Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Introduction to Hemorrhage and Shock Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Introduction to Hemorrhage and Shock Hemorrhage – Abnormal internal or external loss of blood Homeostasis – Tendency of the body to maintain a steady and normal internal environment Shock – Inadequate tissue perfusion – Transition between homeostasis and death Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Hemorrhage is the loss of blood from the vascular space – Reduces the total blood volume – Frequent result of trauma – The most common cause of shock and death in trauma patients May be external (obvious) or internal (hard to detect) Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ The Circulatory System Heart – Two-sided muscular pump with four valves and four chambers Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Heart Provides most of the driving force to move blood through the cardiovascular system – Cardiac output Stroke volume x heart rate – The heart rate is regulated by the autonomic nervous system Sympathetic Parasympathetic Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Heart Stroke volume is the amount of blood pumped from the ventricle with each contraction. Dependent on: – Preload – Afterload – Cardiac contractility The normal heart, at rest, beats about 70 times per minute and moves about 70 mL of blood with each beat. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ The Circulatory System The Vascular System – A series of hollow tubes that distributes blood to and from the various body tissues – Consists of arteries, capillaries, and veins Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Arteries Consist of three distinct tissue layers – Tunica adventicia Strong, fibrous, inelastic tissue – Tunica media Muscular layer Arterioles have greatest ability to change diameter – Tunica intima Smooth inner surface Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Capillaries Capillary flow provides essential nutrients and oxygen and removes waste products. – Only one-cell thick Hydrostatic pressure pushes the plasma into the interstitial space. – Filtration Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Veins Collect blood and return it to the heart Contains the vast majority of the total blood volume – Capacitance system Able to constrict in early stages of hemmorhage Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ The Circulatory System Blood flows through the vascular system because of the pressure differentials – aorta> arterioles>capillaries>venous system>vena cavae Progressive reduction in pressure as blood is moved through the circulatory system Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Blood Blood is the tissue that circulates within the cardiovascular system – A mixture of cells, proteins, water, and other suspended elements Blood Volume – Average adult male has a blood volume of 7% of total body weight – Average adult female has a blood volume of 6.5% of body weight – Normal adult blood volume is 4.5–5 L Remains fairly constant in the healthy body Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Blood Components Erythrocytes: 45% – Hemoglobin – Hematocrit Miscellaneous blood products: <1% – Platelets – Leukocytes Plasma: 54% Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Blood Components Erythrocytes (RBC’s) – The major blood cell—and the most common—is the red blood cell. Contains hemoglobin A molecule to which oxygen attaches – The red blood cell serves as an efficient transporter of oxygen from the lungs to body cells. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Blood Components Plasma – Approximately 92% water The liquid portion of blood – Circulates salts, minerals, sugars, fats, and proteins throughout the body Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Blood Components Leukocytes (WBC’s) – Defend the body against various pathogens (bacteria, viruses, fungi, and parasites) – Produced in bone marrow and lymph glands Release reserves when pathogens invade the body Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Blood Components Platelets – Part of the body’s defense mechanism – Formed in red bone marrow – Work by swelling and adhering together to form sticky plugs (initiating the clotting phenomenon) Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemmorhage Classification Hemorrhage is usually classified by the type of vessel injured – Capillary, venous, or arterial Internal hemorrhage cannot be classified by type with the diagnostic techniques available to paramedics Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Clotting Three-Step Process – Vascular phase Vasoconstriction – Platelet phase Tunica intima damaged Turbulent blood flow Frictional damage to platelets Agglutination and aggregation – Coagulation Release of enzymes Extrinsic – nearby tissue Intrinsic – damaged platelets Fibrin release Normal coagulation in 7–10 minutes Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Clotting Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Clotting The nature of the wound also affects how rapidly and well the clotting mechanisms respond. – Transverse wound – Longitudinal wound Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Factors Affecting Clotting Movement of the wound site Aggressive fluid therapy – Increased BP and displaced clots – Dilution of clotting factors Low body temperature – Ineffective clot formation Medications – ASA, heparin, Ticlid, warfarin (Coumadin) Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Control External Hemorrhage – External hemorrhage is relatively easy to recognize and control. Bleeding from small vessels can often be controlled by firmly bandaging a dressing in place. Fingertip pressure – With careful application of direct pressure you can halt virtually all hemorrhage. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Control Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Control External Hemorrhage (cont.) – If you consider using a tourniquet, be extremely cautious. The need for a tourniquet is rare. – In the absence of perfusion, lactic acid, potassium, and other anaerobic metabolites accumulate Will be released into the circulation when released – Use a wide-band if considering use Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Internal Hemorrhage Can result from: – Blunt or penetrating trauma – Acute or chronic medical illnesses Internal bleeding that can cause hemodynamic instability usually occurs in one of four body cavities: – – – – Chest Abdomen Pelvis Retroperitoneum Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Internal Hemorrhage Signs and symptoms that suggest significant internal hemorrhage include: – Bright red blood from mouth, rectum, or other orifice – Coffee-ground appearance of vomitus – Melena (black, tarry stools) – Orthostatic hypotension Chronic hemorrhage may result in anemia Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Internal Hemorrhage Control General Management – Immobilization, stabilization, elevation – Epistaxis: Nose Bleed Causes: trauma, hypertension Treatment: lean forward, pinch nostrils Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Hemorrhage 60% of body weight is fluid Hemorrhage can be categorized into four progressive stages – Each individual’s response to blood loss may vary It is important to identify: – The length of time elapsed since the incident – The stage of hemorrhage the victim is in when you arrive – How quickly the patient is moving from one stage to another Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Hemorrhage Stage 1 – 15% loss of CBV (circulating blood volume) 70 kg pt = 500–750 mL – Compensation Vasoconstriction Normal BP, pulse pressure, respirations Slight elevation of pulse Release of catecholamines Epinephrine Norepinephrine Anxiety, slightly pale and clammy skin Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Hemorrhage Stage 2 – 15–25% loss of CBV 750–1250 mL – Early decompensation Unable to maintain BP Tachycardia and tachypnea – Decreased pulse strength – Narrowing pulse pressure – Significant catecholamine release Increase PVR Cool, clammy skin and thirst Increased anxiety and agitation Normal renal output Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Hemorrhage Stage 3 – 25–35% loss of CBV 1250–1750 mL – Late decompensation (early irreversible) Compensatory mechanisms unable to cope with loss of blood volume – Classic Shock Weak, thready, rapid pulse Narrowing pulse pressure Tachypnea Anxiety, restlessness Decreased LOC and AMS Pale, cool, and clammy skin Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Hemorrhage Stage 4 – >35% CBV loss >1750 mL – Irreversible Pulse: Barely palpable Respiration: Rapid, shallow, and ineffective LOC: Lethargic, confused, unresponsive GU: Ceases Skin: Cool, clammy, and very pale Unlikely survival Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Hemorrhage Concomitant Factors – Pre-existing condition – Rate of blood loss – Patient Types Pregnant >50% greater blood volume than normal Fetal circulation impaired when mother compensating Athletes Greater fluid and cardiac capacity Obese CBV is based on IDEAL weight (less CBV) Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Hemorrhage Concomitant Factors – Children CBV 8–9% of body weight Poor compensatory mechanisms – Elderly Decreased CBV Medications BP Anticoagulants Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Assessment Assessment of the hemorrhage patient is directed at identifying the source of the hemorrhage. – Halt any serious and controllable loss. Examine the nature of the injury. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Assessment Scene Size-up – Standard precautions are essential – Evaluate the mechanism of injury Time elapsed since injury Determine the amount and rate of blood loss © Jeff Forster Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Assessment Primary Assessment – General Impression Obvious Bleeding – Mental Status – CABC – Interventions Manage as you go O2 Bleeding control Shock BLS before ALS! Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Assessment Secondary Assessment – Rapid Trauma Assessment Full head to toe Consider air medical if stage 2+ blood loss – Focused Physical Exam Guided by c/c – Vitals, SAMPLE, and OPQRST – Additional Assessment Search for signs of internal bleeding Bleeding from body orifice, melena, hematochezia Orthostatic hypotension Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Assessment Ongoing Assessment – Reassess vitals and mental status: Q 5 min: UNSTABLE patients Q 15 min: STABLE patients – Reassess interventions: Oxygen ET IV Medication actions – Trending: improvement vs. deterioration Pulse oximetry End-tidal CO2 levels Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Management Assure that the airway is patent and breathing is adequate. – Maintain the airway and provide the necessary ventilatory support. – Administer high-flow oxygen. Assure that the patient has a palpable carotid pulse. Care for serious (arterial and heavy venous) hemorrhage, immediately after you correct airway and breathing problems. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Management Direct Pressure – Controls all but the most persistent hemorrhage – If bleeding saturates the dressing, cover it with another dressing If ineffective, may be necessary to visualize wound to apply pressure directly to site Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Management Topical Hemostatic Agents – Directly applied to a bleeding wound – Will help to slow or stop the bleeding – Products include: Celox HemCon QuickClot TraumaDEX Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Management Elevation – Reduces the systolic blood pressure – Use elevation only when there is an isolated bleeding wound on a limb Pressure Point – Utilizes an arterial pulse point proximal to the wound – Decreases blood pressure distal to wound Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Management Tourniquet – Consider using a tourniquet only as a last resort when hemorrhage is prolonged and persistent. – Apply a blood pressure cuff just proximal to the hemorrhage site. Inflate to apply pressure 20-30mmHg greater than the systolic blood pressure Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Bleeding Assessment Click here to view an animation on bleeding assessment. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Specific Wound Considerations Head Wounds Neck Wounds – Presentation – Presentation Severe bleeding Skull fracture – Management Gentle direct pressure Fluid drainage from ears and nose Large vessel can entrap air – Management Consider direct digital pressure Occlusive dressing DO NOT pack Cover and bandage loosely Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Specific Wound Considerations Gaping Wounds – Presentation Multiple sites Gaping prevents uniform pressure – Management Bulky dressing Trauma dressing Sterile, nonadherent surface to wound Compression dressing Crush Injury – Presentation Difficult to locate source of bleeding Normal hemorrhage control mechanism non-functional – Management Consider an airsplint and pressure dressing Consider tourniquet Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Transport Considerations Consider rapid transport if: – – – – Suspected serious blood loss Suspected serious internal bleeding Decompensating shock If in doubt, rapid transport indicated Other Considerations – Sympathetic response – Anxiety Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Shock Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Shock Shock is best defined as inadequate tissue perfusion – Transitional stage between normal life, called homeostasis, and death – Can result from a variety of disease states and injuries – Can affect the entire organism, or it can occur at a tissue or cellular level Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cellular Metabolism Cells carry out all the functions performed by the body – Requires oxygen and essential nutrients such as carbohydrates, lipids, and proteins – Produce waste which must be removed – Cells derive most of their energy for essential cell tasks from a molecule called ATP Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cellular Metabolism ATP is a product of the cellular breakdown of glucose – Breakdown occurs in three steps Glycolysis Does not require oxygen Produces pyruvic acid and 2 ATP’s Kreb’s Cycle Requires oxygen Converts pyruvic acid into water, carbon dioxide and 2 ATP’s Electron transport chain Occurs in mitochondria Results in the production of 32 ATPS Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cellular Metabolism If oxygen and glucose are in good supply, the cell has ample energy to perform its functions If oxygen is in short supply, the cells generate energy only from glycolysis, thereby gaining only a small amount of energy and accumulating pyruvic acid – Converts to lactic acid – Accumulation results in metabolic acidosis Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Oxygen Transport Transport involves ventilation, external respiration, circulation and internal respiration. The environment provides 21 percent oxygen under the normal atmospheric (at sea level) pressure. – Certain conditions may result in less available oxygen. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Oxygen Transport Air moves from the environment to the alveoli by ventilation. – Requires patent airways and functional “bellows” system. At the alveoli, oxygen must traverse the alveolar/capillary membrane. – Diffusion – Movement of oxygen from the alveolus to the red blood cell is external respiration. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Oxygen Transport Oxygen must uptake on the hemoglobin molecule. – Efficiently carries 97% of the oxygen – Remaining 3% dissolves in plasma The cardiovascular system then moves the red blood cells from the pulmonary system, through the heart, through the arterial system and into the tissues. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Oxygen Transport In the capillaries oxygen diffuses across the capillary wall, into the interstitial fluid and then to the cell. – Internal respiration Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cellular Metabolism The cardiovascular system is also responsible to help maintain other elements of the homeostatic environment – Removal of CO2 and water – Heat regulation – Provides the glucose necessary for the cellular metabolism Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Digestion, Filtration, Hormone Production, Excretion The digestive system absorbs carbohydrates and lipids (fats), moving them through the portal system to the liver for processing. The pancreas regulates blood glucose. – Glucagon increases blood glucose – Insulin decreases blood glucose Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Digestion, Filtration, Hormone Production, Excretion Role of the Kidneys – Regulating the body’s fluid/electrolyte balance Excreting excess sodium, potassium, chloride, calcium, bicarbonate, and magnesium – Excreting the waste products of metabolism – Excrete or retain water Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Circulation The cardiovascular system – Responsible for assuring that the necessary materials travel to and from the body’s cells – Cardiac output Preload, cardiac contractility, and afterload Systolic blood pressure is most indicative of the strength and volume of cardiac output Lowest pressure in the arteries is the diastolic blood pressure Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Circulation Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Circulation Microcirculation – Blood flow in the arterioles, capillaries, and venules – Sphincter functioning Most organ tissue requires blood flow 5 to 20% of the time Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Microcirculation Venules and veins serve as collecting channels and storage vessels (capacitance) Normally contain 70% of the blood volume Muscular movement aids in blood return to the heart Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Circulation Respiration also facilitates blood return to the heart – Changes in pressure draws blood towards the heart Thoracoabdominal pump In states of hypovolemia, blood return to the heart is diminished – Reduces cardiac output, arterial blood pressure, and the body’s ability to direct blood flow to critical organs Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cardiovascular System Regulation The human body is controlled by the autonomic branch of the nervous system. – Parasympathetic branch – Sympathetic branch These two systems act in balance Many sympathetic nervous system activities are aimed at defending the organism. – These mechanisms may be detrimental in shock states Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cardiovascular System Regulation Parasympathetic Nervous System Decrease – Heart rate – Strength of contractions – Blood pressure Increase – Digestive system – Kidneys Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cardiovascular System Regulation Sympathetic Nervous System Increase – – – – Body activity Heart rate Strength of contractions Vascular constriction Bowel and digestive viscera Decreased urine production – Respirations – Bronchodilation Increases skeletal muscle perfusion Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cardiovascular System Regulation A system of receptors, autonomic centers, and nervous and hormonal interventions maintains control over the cardiovascular system Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cardiovascular System Regulation Baroreceptors in the aortic arch and in the carotid sinuses monitor the arterial blood pressure Chemoreceptors monitor carbon dioxide levels in the bloodstream Three specific centers help regulate cardiovascular function – Cardioacceleratory center, the cardioinhibitory center, and the vasomotor center Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cardiovascular System Regulation Hormonal Regulation – Epinephrine and norepinephrine are sympathetic agents Most rapid hormonal response to hemorrhage Both have A1 properties causes vasoconstriction Epinephrine has beta-1 and beta-2 properties B1= increased rate, strength, and conductivity B2= broncodilation Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hormonal Regulation Antidiuretic Hormone (ADH) – Arginine Vasopressin (AVP) – Released Posterior pituitary Drop in BP or increase in serum osmolarity – Action Increase in peripheral vascular resistance Increase water retention by kidneys Decrease urine output Splenic vasoconstriction 200 mL of free blood to circulation Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hormonal Regulation Angiotensin – Released Primary chemical from kidneys Stimulus is lowered BP and decreased perfusion – Action Converted from renin into angiotensin I Modified in lungs to angiotensin II Potent systemic vasoconstrictor Causes release of ADH, aldosterone, and epinephrine Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hormonal Regulation Aldosterone – Release Adrenal cortex Stimulated by angiotensin II – Action Maintain kidney ion balance Retention of sodium and water Reduce insensible fluid loss Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hormonal Regulation Glucagon – Release Alpha cells of pancreas Triggered by epinephrine – Action Causes liver and skeletal muscles to convert glycogen into glucose Gluconeogenesis Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hormonal Regulation Insulin Erythropoietin – Release – Release Beta cells of pancreas – Action Facilitates transport of glucose across cell membrane Kidneys Hypoperfusion or hypoxia – Action Increases production and maturation of RBCs in the bone marrow Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hormonal Regulation Adrenocorticotropic hormone – Stimulates the release of glucocorticoids from the adrenal cortex Increases glucose production Reduces the body’s inflammation response Prolongs clotting time, wound healing, and infection fighting processes Growth hormone – Promotes the uptake of glucose and amino acids in the muscle cells Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ The Body’s Response to Blood Loss As stroke volume decreases, cardiac output decreases resulting in decreased systolic BP – Carotid and aortic baroreceptors recognize this decrease in blood pressure Stimulate the cardiovascular center of the medulla oblongata Mechanisms compensate for small blood losses Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ The Body’s Response to Blood Loss Cellular Ischemia – Constriction of arterioles means that less and less blood is directed to the noncritical organs Results in hypoxia – Anaerobic metabolism results Followed by ischemia Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cellular Ischemia If blood loss continues, waste products accumulate and blood becomes acidic. – Increase in depth and rate of respirations – Decreased LOC – Increased circulating catecholamines causes anxiousness, restlessness, and possibly a combative patient – Decreased myocardial oxygen supply Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Cellular Ischemia If the blood loss stops, the blood draws fluid from within the interstitial space – Up to 1 L per hour Kidneys reduce urine output Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ The Body’s Response to Blood Loss Capillary Microcirculation – Sympathetic stimulation and reduced perfusion to the kidneys, pancreas, and liver cause the release of hormones Angiotensin II causes reduced blood flow – Perfusion is further limited to only those organs most critical to life More cells begin to use anaerobic metabolism for energy = Increased acids Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Capillary Microcirculation The build-up of lactic acid and carbon dioxide relaxes the precapillary sphincters Postcapillary sphincters remain closed Capillary and cell membranes begin to break down Red blood cells begin to clump together – Rouleaux Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ The Body’s Response to Blood Loss Capillary Washout – Acidosis finally causes relaxation of the postcapillary sphincters – Washout causes profound metabolic acidosis and microscopic emboli – Body moves quickly and then irreversibly toward death Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Shock Process of shock can be divided into three stages: – Compensated – Decompensated – Irreversible Stages are progressively more serious Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Shock Compensated Shock – The body is capable of meeting its critical metabolic needs through a series of progressive compensating actions. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Compensated Shock The first recognizable response to serious blood loss is an increase in pulse rate. – The first sign usually attributable to shock is a narrowing pulse pressure. Vasoconstriction causes the patient’s skin to become pale, cyanotic, or ashen. The victim becomes anxious, restless, or combative. The patient may experience air hunger and tachypnea. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Shock Decompensated Shock – Mechanisms that initially compensated for blood loss now fail – Systolic BP drops significantly – Increasing tachycardia and vasoconstriction are ineffective Vital organs are no longer perfused – Patient displays a rapidly dropping level of responsiveness Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Shock Irreversible Shock – The body’s cells are so badly injured and die in such quantities that the organs cannot carry out their normal functions. – Aggressive resuscitation will be ineffective. – The longer a patient is in decompensated shock, the more likely he has moved to irreversible shock. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Stages of Shock Click here to view an animation on hypovolemic shock. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Etiology of Shock Shock can have many causes Classifications according to origin: – Hypovolemic, distributive, obstructive, cardiogenic, and respiratory Patients in shock present with similar signs and symptoms and suffer similar systemic complications. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Etiology of Shock Hypovolemic – Caused by any significant reduction in the cardiovascular system volume – Causes Hemorrhage (internal or external) Plasma losses Protracted vomiting, diarrhea, sweating, and urination “Third-space” losses Fluid shifts into various body compartments Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Etiology of Shock Distributive Shock – Mechanisms that interfere with the ability of the vascular system to distribute the cardiac output – Causes Neurogenic Anaphylactic Sepsis Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Etiology of Shock Obstructive – Results from interference with the blood flowing through the cardiovascular system – Causes Tension pneumothorax Cardiac tamponade Pulmonary emboli Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Etiology of Shock Cardiogenic Shock – Results from a problem with the cardiovascular pump – Causes Infarction Disturbances in the cardiac electrical system Failure of the valves Cardiac rupture Reduced cardiac pumping action – May present with the signs and symptoms of myocardial infarction or pulmonary edema Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Etiology of Shock Respiratory Shock – Occurs when the respiratory system is not able to bring oxygen into the alveoli and remove carbon dioxide – Causes Flail chest Respiratory muscle paralysis Pneumothorax Pulmonary edema Tension pneumothorax Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Etiology of Shock Neurogenic Shock – Results from an interruption in the communication pathway between the central nervous system and the rest of the body – Causes Spinal injury Skin remains warm and dry above injury site Head injury Temporary or permanent – Body’s compensatory mechanisms are often affected Tachycardia and increased diastolic are not present Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Shock Assessment You must be able to recognize shock as early as possible in your patient assessment. Search out the signs and symptoms of shock in each phase of the assessment process. Carefully monitor for the development or progression of shock. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Shock Assessment Scene Size-up – Analyze the forces that caused the trauma. Possibility of both external and internal injury. – Look for mechanisms that might result in internal chest, abdominal, or pelvic injuries. – Observe for external hemorrhage. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Shock Assessment Initial Assessment – Determine the patient’s level of consciousness, responsiveness, and orientation. – Assess the airway for patency and breathing for adequacy. Administer high-concentration oxygen. – Note the heart rate and pulse strength. Skin color and temperature. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Initial Assessment Pulse oximetry – If you note erratic or intermittent readings with the device, suspect increasing cardiovascular compensation. Capnography – Decreased ETCO2 levels Reflect cardiac arrest, shock, pulmonary embolism, or incomplete airway obstruction – Increased ETCO2 levels Reflect hypoventilation, respiratory depression, or hyperthermia Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Focused History and Physical Exam Vary with the patient’s priority as determined by the initial assessment Patients who have no significant mechanism of injury – Perform an assessment focused on the area of injury Trauma patients who have signs or symptoms of serious injury – Continue spinal motion restriction and perform a rapid trauma assessment Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Rapid Trauma Assessment When you have a trauma patient with significant signs and symptoms of injury, perform a rapid trauma assessment. © Jeff Forster Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Rapid Trauma Assessment Inspect and palpate the patient from head to toe. Pay special attention to the areas most likely to produce serious, life-threatening injury. Rule out the possibility of obstructive shock. Set the patient’s priority for transport and for injury care. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Detailed Patient Assessment Consider the detailed physical exam only after all priorities have been addressed and the patient is either en route to the trauma center or during prolonged extrication. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Ongoing Assessment Perform serial ongoing assessments – Mental status, airway, breathing, and circulation – Perform the ongoing assessment every 5 minutes in the serious trauma patient Pay particular attention to the pulse rate and pulse pressure Check the adequacy and effectiveness of any interventions you have performed Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Airway and Breathing Management Assure good ventilations with supplemental high-flow, high-concentration oxygen Overdrive respiration may be indicated with: – Rib fractures – Flail chest – Spinal injury with diaphragmatic respirations – Head injury © Craig Jackson/In the Dark Photography Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Airway and Breathing Management Positive end-expiratory pressure (PEEP) and continuous positive airway pressure (CPAP) Protect the airway with an oral airway, nasal airway or possibly, endotracheal intubation Provide pleural decompression as necessary Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Hemorrhage Control Provide ongoing hemorrhage control as previously described. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Fluid Replacement The field treatment of choice for significant blood loss in trauma is whole blood. – Generally not practical in the field setting – Most practical fluid for prehospital administration is an isotonic crystaloid Polyhemoglobins – – – – Contain either animal or human hemoglobin Prolonged shelf life Relatively inexpensive Efficacy not well established Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Fluid Replacement Isotonic Fluid Replacement – The standard for shock treatment in the prehospital setting – Current approach to fluid administration Begin fluid resuscitation when blood pressure falls to below 75 percent of normal or about 90mmHg systolic. Observe the patient’s level of consciousness and other signs and symptoms. Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Isotonic Fluid Replacement Employ aggressive fluid resuscitation – Use lactated Ringer’s solution or normal saline via two lines – Administer until blood pressure returns to 100 mmHg and the level of consciousness increases In children, infuse 20 mL/kg of body weight Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Isotonic Fluid Replacement Consider the internal lumen size of both the catheter and the administration set – Utilize largest bore possible – Catheter length and fluid pressure Ideal catheter for the shock patient is relatively short, 1 1/2" or shorter Cautiously control fluid volume – Maintain V/S, don’t increase them Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Shock Management Temperature Control – Conserve core temperature – Warm IV fluids PASG – Action Increase PVR Reduce vascular volume Increase central CBV Immobilize lower extremities – Assess Pulmonary edema Pregnancy Vital signs © Craig Jackson/In the Dark Photography Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Shock Management Pharmacological Intervention – Pharmacological interventions are generally limited – Cardiogenic shock Fluid challenge Dopamine – Distributive shock Fluid challenge Dopamine PASG Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ Summary Introduction to Hemorrhage and Shock Hemorrhage Shock Bledsoe et al., Paramedic Care: Principles & Practice, Volume 4: Trauma Emergencies, 3rd. Ed. © 2009 by Pearson Education, Inc. Upper Saddle River, NJ