Chapter 40 ALS Assist Introduction • You may need to be familiar with AEMT and paramedic skills. • These include: – Advanced airway techniques – Intravenous (IV) therapy – Cardiac monitoring Advanced Airway Techniques • Establishing and maintaining an airway is the single most important EMT skill. – Most conscious patients can maintain their own airway. – Other patients may require an oropharyngeal or nasopharyngeal airway. – Advanced airway management provides better airway protection and ventilation. Anatomy and Physiology of the Airway (1 of 5) • The respiratory system consists of all the body structures used for breathing. – Upper airway includes the nose, mouth, throat (pharynx), and larynx (vocal cords). – Lower airway includes the trachea, bronchi, and lungs. Anatomy and Physiology of the Airway (2 of 5) Anatomy and Physiology of the Airway (3 of 5) • The respiratory system: – Delivers oxygen to body – Removes carbon dioxide • This process takes place on two levels: – Alveolar-capillary exchange – Capillary-cellular exchange Anatomy and Physiology of the Airway (4 of 5) Anatomy and Physiology of the Airway (5 of 5) • Each living cell of the body requires a regular supply of oxygen. – Some cells, such as those in the heart, brain, and nervous system, need a constant supply to survive. – Other cells can tolerate short periods without oxygen. Basic Airway Management (1 of 2) • Always assess the airway first in an injured or ill patient. • Open the airway. – Use the head tilt–chin lift maneuver in a patient with no suspected spinal injury. – Use the jaw-thrust maneuver if there is a possibility of spinal injury. Basic Airway Management (2 of 2) • Assess the airway and evaluate the need for suctioning to remove: – Foreign bodies – Liquid – Blood • Determine if the patient needs an airway adjunct. Endotracheal Intubation (1 of 2) • Insertion of a tube into the trachea to maintain the airway – If done through the mouth, it is called orotracheal intubation. – If done through the nose, it is called nasotracheal intubation. – Tube passes directly through the larynx between the vocal cords and trachea. Endotracheal Intubation (2 of 2) • Very effective method • Indicated for: – Patients who cannot protect their own airway – Patients who need prolonged artificial ventilation Equipment (1 of 8) • Assemble all the equipment. – Laryngoscope handle and blade – Properly sized endotracheal (ET) tube – Stylet – 10-mL syringe – Water-soluble lubricant for the ET tube – Suction unit with rigid and soft-tip catheters Equipment (2 of 8) • Assemble all the equipment (cont’d). – Magill forceps – Stethoscope – Commercial securing device – Secondary confirmation device Equipment (3 of 8) • Laryngoscope – Used to sweep the tongue out of the way and align the airway so the vocal cords can be visualized • Endotracheal tubes – Proper-sized tube for adults ranges from 7.0 to 8.5 mm Equipment (4 of 8) Equipment (5 of 8) • Endotracheal tubes (cont’d) – Use the largest-diameter ET tube that will pass easily through the vocal cords. – For children, use a resuscitation tape device. – A standard 15/22-mm adapter attaches to any ventilation device. Equipment (6 of 8) Equipment (7 of 8) • Stylet – Inserted into the ET tube to add rigidity and shape during intubation – Bend the tip to form a gentle curve. – Do not insert past Murphy’s eye. Equipment (8 of 8) • Syringe – Use a 10-mL syringe to test for air leaks in the ET tube before intubation. • Other equipment – A suction unit may be needed to clear secretions or blood. – A commercial securing device ensures that the tube does not move. The Sellick Maneuver • Can be used to intubate a patient who has no cough and/or gag reflex • Helps reduce the chance of regurgitation and aspiration of stomach contents • Follow the steps in Skill Drill 40-1. – Be sure to correctly identify anatomic landmarks. The Intubation Procedure (1 of 7) • You may intubate only if authorized by offline or online medical control. • Be sure to use standard precautions. • An intubation attempt should not take more than 30 seconds. – Begins when ventilation stops and the laryngoscope blade is inserted – Ends when ventilation begins again The Intubation Procedure (2 of 7) • Intubation is a multiple-person task. – First EMT applies and uses the AED. – Second and third EMTs perform CPR at a ratio of 30 compressions to 2 ventilations. – Fourth EMT prepares and intubates the patient. • Follow the steps in Skill Drill 40-2 to perform orotracheal intubation. The Intubation Procedure (3 of 7) • You must use a secondary method of confirming proper tube placement. – Esophageal detector devices – End-tidal carbon dioxide detectors – Capnography monitors – These devices are not 100% guaranteed. The Intubation Procedure (4 of 7) Source: The LIFEPAK® 15 defibrillator monitor courtesy of Physio-Control. Used with permission of Physio-Control, Inc., and according to the Material Release Form provided by Physio-Control. The Intubation Procedure (5 of 7) • Primary confirmation is: – Direct visualization of the tube passing through the vocal cords – Auscultating good bilateral breath sounds – Seeing the patient’s chest rise and fall with each ventilation • Never let go of the ET tube until it is secured. The Intubation Procedure (6 of 7) • Intubation complications – Intubating the right main stem bronchus – Intubating the esophagus – Aggravating spinal injury – Increased hypoxia – Patient vomiting The Intubation Procedure (7 of 7) • Intubation complications (cont’d) – Laryngospasm – Trauma – Mechanical failure – Patient intolerant of the endotracheal tube – Decrease in heart rate Multilumen Airways (1 of 4) • Advanced airways that do not require visualization of the vocal cords for placement The Combitube – Examples include the Combitube and pharyngeotracheal lumen airway. Multilumen Airways (2 of 4) Multilumen Airways (3 of 4) • Contraindications – Conscious or semiconscious patients with a gag reflex – Children younger than 14 years – Adults shorter than 5′ – Patients who have ingested a caustic substance – Patients who have an esophageal disease Multilumen Airways (4 of 4) • Removing the multilumen airway – If the patient will no longer tolerate the airway, it should be removed. – Remember that the patient will likely vomit when the airway is removed, so a suction unit must be readily available. – Simply deflate both balloon cuffs and gently remove the tube. Single Lumen Airway (1 of 3) • King LT airway – Single lumen airway that is blindly inserted into the esophagus – Consists of a curved tube with ventilation ports located between two inflatable cuffs – Intended in patients who are taller than 4′ Single Lumen Airway (2 of 3) Source: Courtesy of King Systems Single Lumen Airway (3 of 3) • Laryngeal mask airway – Consists of two parts: the tube and the mask or cuff – After blind insertion, the device molds and seals itself around the laryngeal opening by inflation of the mask. Gastric Tubes (1 of 2) • Sometimes a patient may require placement of a tube through the nose or mouth that extends into the stomach. – Cardiac arrest patients – A nasal or oral gastric tube relieves gastric distention. – May be used by ED staff to lavage the stomach in cases of overdose Gastric Tubes (2 of 2) • Proper placement can be confirmed by: – Aspiration of stomach contents with a syringe – Listening with a stethoscope as air is introduced into the tube with a syringe – Radiograph on arrival at the ED Continuous Positive Airway Pressure (1 of 3) • Used in breathing patients who are alert and able to follow commands and have reduced function of the alveoli due to: – Congestive heart failure – Chronic obstructive pulmonary disease – Asthma Continuous Positive Airway Pressure (2 of 3) • A tight-fitting mask is placed over the mouth and nose and connected to an oxygen source. – Delivers flow rates of at least 50 L/min – May be helpful in patients with severe respiratory distress Continuous Positive Airway Pressure (3 of 3) Courtesy of Respironics, Inc., Murraysville, PA. All rights reserved. Intravenous Therapy • Develop a routine to follow as you assemble the appropriate equipment. – This will help you keep track of your equipment and the steps necessary to complete successful IV administration. Indications • Many medications used by ALS crews are given by the IV route. • A fluid bolus may be indicated for patients who: – Are dehydrated because of vomiting or excessive diarrhea – Have experienced blood loss because of hemorrhage Assembling the Equipment Choosing an IV Solution (1 of 3) • In the prehospital setting, the choice of IV solution is limited to: – Isotonic crystalloids – Normal saline – Lactated Ringer’s solution • D5W is often reserved for administering medication. Choosing an IV Solution (2 of 3) • Each IV solution bag is wrapped in a protective sterile plastic bag. – Guaranteed to remain sterile until the posted expiration date – Once the wrap is torn, the IV solution has a shelf life of 24 hours. Choosing an IV Solution (3 of 3) • The bottom of each bag has two ports: – An injection port for medication – An access port for connecting the administration set • The more common prehospital volumes are 1,000 mL and 500 mL. Choosing an Administration Set (1 of 3) • An administration set moves fluid from the IV bag into the patient’s vascular system. – Each set has a piercing spike protected by a plastic cover. Choosing an Administration Set (2 of 3) • Drip sets come in two primary sizes. – A microdrip set allows 60 gtt/mL. – A macrodrip set allows 10 to 15 gtt/mL. Choosing an Administration Set (3 of 3) • Preparing an administration set – Verify the solution and check for clarity. – To spike the bag with the administration set, follow the steps in Skill Drill 40-3. – Saline locks (buff caps) are a way to maintain an active IV site without running fluids through the vein. Catheters • Hollow, laser-sharpened needle inside a hollow plastic tube that is inserted into a vein • Select the catheter size based on the: – Need for the IV – Condition of the patient’s veins – Location for the IV Starting an IV (1 of 2) • Apply a tourniquet proximal to the site where venipuncture is to be performed. • When a suitable vein is identified, the area should be cleaned. • The needle/catheter is introduced into the vein, the needle withdrawn and disposed of properly, and IV tubing or lock placed. Starting an IV (2 of 2) • Use tape or a commercially available device to secure the catheter. • Always wear gloves during the procedure. • Skill Drill 40-4 covers how to start an IV. Securing the Line • Tape the area so that the catheter and tubing are securely anchored in case of a sudden pull on the line. • Avoid circumferential taping around any extremity because it can act like a constricting band and stop circulation. Alternative IV Sites and Techniques (1 of 2) • Intraosseous (IO) needles – Used for emergency venous access when other IV access is difficult or impossible – Often patients are experiencing a lifethreatening situation. – Generally inserted in the proximal tibia Alternative IV Sites and Techniques (2 of 2) • External jugular IV – Provides venous access through the external jugular veins in the neck – Catheter is inserted midway between the angle of the jaw and the midclavicular line. – Punctures can be difficult because these veins are surrounded by a very tough, fibrous sheath. Possible Complications of IV Therapy • Local reactions include problems like infiltration and phlebitis. • Systemic complications include allergic reactions and circulatory overload. Local IV Site Reactions (1 of 4) • Infiltration – Escape of fluid into the surrounding tissue when the IV catheter is not in the vein – Can cause a localized are of edema or swelling – Stop the flow, remove the catheter, and reinsert it at an alternative site. Local IV Site Reactions (2 of 4) • Phlebitis – Inflammation of the vein – Not usually seen in emergency prehospital patients – Associated with fever, tenderness, and red streaking along the vein Local IV Site Reactions (3 of 4) • Occlusion – Physical blockage of a vein or catheter • Vein irritation – More common with IV medication administration and very uncommon with administration of pure IV fluids – Patients often complain immediately that the IV is bothering them. Local IV Site Reactions (4 of 4) • Hematoma – Accumulation of blood in the tissues surrounding an IV site – Result from vein perforation or catheter removal – If a hematoma develops when IV catheter insert is attempted, the procedure should stop. Systemic Complications (1 of 7) • A systemic complication can evolve from reactions or complications associated with IV insertion. – Usually involve other body systems and can be life threatening • Allergic reactions – True anaphylaxis is possible and must be treated aggressively. Systemic Complications (2 of 7) • Allergic reactions (cont’d) – Can be related to a person’s unexpected sensitivity to an IV fluid or medication – Discontinue the IV fluid and remove the solution, maintain the airway, and monitor ABCs and vital signs. Systemic Complications (3 of 7) • Air embolus – Patients who are already ill or injured can be adversely affected if air is introduced into the circulatory system. – Properly flush the IV line. – Treat a patient by placing him or her on the left side with the head down. Systemic Complications (4 of 7) • Circulatory overload – An unmonitored IV bag can lead to circulatory overload. – Problems occur when the patient has cardiac, pulmonary, or renal dysfunction. – The most common cause in the prehospital setting is failure to readjust the drip rate after flushing an IV line. Systemic Complications (5 of 7) • Circulatory overload (cont’d) – To treat a patient: • Slow the IV rate to keep the vein open. • Raise the patient’s head to ease respiratory distress. • Administer high-flow oxygen. • Monitor vital signs and shortness of breath. Systemic Complications (6 of 7) • Vasovagal reactions – Some patients have anxiety concerning needles or in response to the sight of blood. – Patients can present with anxiety, diaphoresis, nausea, or syncopal episodes. – Lower the head of the stretcher, administer oxygen, and monitor vital signs. Systemic Complications (7 of 7) • Catheter shear – Potential complication when starting an IV – Could have a devastating effect on your patient – May occur if you attempt to reinsert the needle through the catheter after the needle has been partially withdrawn Troubleshooting • Several factors influence IV flow rate. • Perform the following checks after completing IV administration. – Check your administration set. – Check the height of the IV bag. – Check the type of catheter used. – Check the tourniquet. Age-Specific Considerations (1 of 2) • IV therapy for pediatric patients – A child has smaller veins. – A small-gauge catheter should be used (22-gauge to 24-gauge). – Volume control is important. – Use a special type of microdrip set called a Volutrol, which fills the large drip chamber with a specific amount of fluid. Age-Specific Considerations (2 of 2) • IV therapy for geriatric patients – Smaller catheters may be preferable. – The use of tape can lead to skin damage, so be careful when taping IV catheters and tubing. – Be careful when using macrodrips because they can allow infusion of fluids, which may lead to fluid overload. Cardiac Monitoring • 12-lead ECG can help in the early identification of an acute myocardial infarction (AMI). – The interpretation of cardiac rhythm may not be an EMT skill. – However, it is helpful to be able to place electrodes and leads. Electrical Conduction System (1 of 2) • Network of specialized tissue capable of conducting electrical current throughout the heart • Contains: – Sinoatrial (SA) node – Three intermodal pathways – Atrioventricular (AV) node – Bundle of His – Right and left bundle branches Electrical Conduction System (2 of 2) Electrodes and Waves • The ECG electrodes pick up the electrical activity of the heart, and the ECG machine converts them to waves. • The way an ECG tracing looks depends on where the lead is placed. The ECG Complex (1 of 3) • One complex represents one beat in the heart. • The complex consists of several waves: the P, QRS, and T waves. • A segment is a specific portion of the complex. The ECG Complex (2 of 3) The ECG Complex (3 of 3) • An interval is the distance, measured in time, occurring between two cardiac events. – The time between the beginning of the P wave and the beginning of the QRS complex is known as the P-R interval. ECG Paper • The paper on which an ECG is recorded contains a grid. – Each little box represents 1/25 of a second, or 0.04 second. – Each bigger box is composed of five smaller boxes, or 0.20 second. – Five big boxes equal 1 second. Normal Sinus Rhythm (1 of 2) • Sinus rhythm is a rhythm in which the SA node acts as the pacemaker. • With normal sinus rhythm: – All of the P waves should be the same. – The heart rate should be between 60 and 100 beats/min. Normal Sinus Rhythm (2 of 2) The Formation of the ECG (1 of 3) • Production of the heart’s rhythm is a continuous process, with no actual period of rest or inactivity. • If the heart is functioning normally, the process will repeat over and over continuously. The Formation of the ECG (2 of 3) The Formation of the ECG (3 of 3) Arrhythmias (1 of 5) • Abnormal rhythm of the heart • Sinus bradycardia – Consistent P waves, consistent P-R intervals, regular heart rate less than 60 beats/min Source: From Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD. Arrhythmias (2 of 5) • Sinus tachycardia – Consistent P waves, consistent P-R intervals, regular heart rate more than 100 beats/min – May cause a decrease in cardiac output Source: From Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD. Arrhythmias (3 of 5) • Ventricular tachycardia – Presence of three or more abnormal ventricular complexes in a row with a rate of more than 100 beats/min – Very regular rhythm Source: From Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD. Arrhythmias (4 of 5) • Ventricular fibrillation – Rapid, completely disorganized ventricular rhythm with chaotic characteristics – Undulations of varying shapes and sizes; no specific pattern; no discernable P, QRS, or T waves – No organized beating of the heart Source: From Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD. Arrhythmias (5 of 5) • Asystole – Complete absence of any electrical cardiac activity – Patient is clinically dead at this point. Source: From Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD. Assisting With Cardiac Monitoring • You may have a 4-lead ECG or a 12-lead ECG system. • New cardiac monitors include several new features using modern technology. • They are compact, light, and portable and combine defibrillation and monitoring capabilities. Lead Placement (1 of 5) • A 4-lead ECG uses four leads, which are electrodes attached to wires. • The four leads are called the limb leads. – White lead on the right shoulder or arm – Black lead on the left shoulder or arm – Green lead on the right low abdomen/leg – Red lead on the left low abdomen/leg Lead Placement (2 of 5) • It does not matter where the leads are placed on the limbs, as long as all four are at least 10 cm from the heart. Lead Placement (3 of 5) • For the 12-lead ECG, electrodes are placed as a 4-lead placement as well as in very specific locations on the chest. – V1 and V2 on each side of the sternum – V4 at the midclavicular line – V3 between V2 and V4 – V5 at the anterior axillary line, and V6 in the midaxillary line Lead Placement (4 of 5) Lead Placement (5 of 5) • It is very important to have direct skin contact when obtaining an ECG. – If the skin is wet or oily, wipe and clean the skin thoroughly. – If the skin is hairy, use a razor. • Advantages of 12-lead monitoring – Early identification of acute ischemia – Accurate identification of arrhythmias ST-Segment Elevation Myocardial Infarction (STEMI) • Specific type of myocardial infarction in which the ST segment of the cardiac cycle is elevated • Treatable by techniques that rapidly restore perfusion to the coronary arteries – “Time is muscle.” Summary (1 of 3) • There may be cases in which an EMT may find it necessary to be familiar with skills normally practiced at the AEMT and paramedic level. These skills include advanced airway techniques, IV therapy, and cardiac monitoring. Summary (2 of 3) • An advanced airway technique is endotracheal intubation, the insertion of a tube into the trachea to maintain the airway. • Additional advanced airway care devices include the Combitube, pharyngeotracheal lumen airway, the King LT, and the laryngeal mask airway. Summary (3 of 3) • IV therapy is used to replace fluids in a patient with shock or to administer medications. • Cardiac monitoring with an ECG is an advanced skill that the EMT may provide in assistance to the AEMT or paramedic.