Module - 4 - Respiratory Emergencies Flashcards
- You are transporting a thirty-year-old man involved in a MCA from a rural area facility. The 70-kg patient is on a ventilator with the following settings: FIO2 1.0, Vt 500, rate 16, PIP 22, and PEEP 5. The ABG results are pH 7.01, pCO2 68, HCO2 12, pO2 280. Interpretation of the blood gas reveals
A. Metabolic and respiratory acidosis
B. Metabolic acidosis
C. Respiratory acidosis
D. Compensated respiratory acidosis
- A: Metabolic and respiratory acidosis. The pCO2 is high, resulting in a respiratory acidosis, and the pH and HCO3 are low, resulting in a metabolic acidosis. Review
- You are transporting a ten-year-old boy weighing 60 kg with diagnosis of status asthmaticus on a ventilator. EtCO2 is 56 and pulse oximetry reading is 95%. Ventilator settings are at Vt 450, FIO2 1.0, Rate 16, I:E 1:2, PEEP 5, PIP 48. How will you manage this patient?
A. Increase tidal volume
B. Reduce I:E ratio
C. Increase PEEP
D. Increase respiratory rate
- B: The normal inspiration-to-expiration (I:E) ratio to start is 1:2. This is reduced to 1:4 or greater in the presence of obstructive airway disease (asthma, COPD) in order to avoid air-trapping (breath stacking) and auto-PEEP or intrinsic PEEP (iPEEP).
- When inserting a chest tube, correct insertion site recommended is
A. 2nd ICS midclavicular line
B. 4th-5th ICS anterior axillary line
C. 4th ICS midaxillary line
D. 5th ICS midaxillary line
- B: The chest tube is inserted in the area called the “safe zone,” a region bordered by the lateral border of the pectoralis major, a horizonatal line inferior to the axilla, the anterior border of latissimus dorsi, and a horizonatal line superior to the nipple, which defines the fifth intercostal space of the anterior midaxillary line.
- ABG’s reveal pH 7.31, pCO2 58, Bicarb 26, pO2 106. What is your interpretation?
A. Metabolic acidosis
B. Respiratory acidosis
C. Metabolic alkalosis
D. Respiratory alkalosis
- B: Respiratory acidosis. The pH is low and the pCO2 is high, indicating acidosis, so the primary disorder is respiratory acidosis. There is no indication of metabolic compensation.
- A patient in early shock most probably has which acid-base imbalance?
A. Metabolic acidosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Respiratory alkalosis
- D: Respiratory alkalosis can be present initially as evidenced by an increase in respiratory rate in early shock as the body attempts to compensate for blood/volume loss in the compensatory stage. Other early signs of shock in the compensatory stage can include increase in heart rate, narrowing pulse pressure, and thirst.
- Your patient’s ABG’s are: pH 7.43, pCO2 56, HCO3 34. You should correct the pCO2 by
A. Hyperventilation
B. Ventilating at physiologic norms but greater than the patient’s spontaneous rate
C. Paralyze the patient to completely control vent rate
D. Analyze electrolytes and replace deficiency
- D: The pH is normal and the HCO3 is high, indicating a metabolic alkalosis. The pCO2 is high, indicating compensatory response. Since the pH is normal, the patient is completely compensated.
- A fifty-five-year-old woman complains of SOB for 2 days. Identify what the following ECG rhythm reveals. [image ST elevation in V1-4]
A. Inferior MI
B. Anteroseptal MI
C. Lateral wall MI
D. Posterior MI
- B: Antero-septal MI as evidenced by ST elevation of >2 mm in two more contiguous leads in V1-V4.
- Electrical alternans may be caused by
A. Pericardial effusion
B. Pulmonary embolus
C. Tension pneumothorax
D. Diaphragmatic rupture
- A: Pericardial effusion. Electrical alternans is an ECG alteration of the QRS complex amplitude or axis between heart beats. It is thought to be associated to changes in the ventricular axis due to fluid in the pericardium. Pericardial effusion can lead to cardiac tamponade.
- You are on the scene of a thirty-year-old man involved in a single vehicle, chest has been decompressed with a needle. The patient is orally intubated and continues to desaturate, and you note an increase in SQ air on the left side of the chest and neck. The next intervention will be to
A. Reneedle the left chest
B. Insert a chest tube
C. Advance ET tube below the level of the injury; right main stem intubation
D. Decrease respiratory rate down to 10 per minute
- C: A pneumothorax with a persistent air leak or failure of a lung to re-expand after needle thorocostomy and/or chest tube has been placed should lead the transport team to suspect a tracheobronchial injury. A tension pneumothorax may be the first visible sign of the problem. Other signs/symptoms can include hemoptysis, respiratory distress, subcutaneous, and/or mediastinal emphysema. Tracheobronchial injuries occur most often from blunt trauma. Penetrating thoracic trauma is a less common cause. If tracheobronchial injury is suspected, immediate endotracheal intubation is performed with placement of the endotracheal tube below the level of the injury.
- Your patient presents with a history of asthma, coronary artery disease, hypertension, and has a chief complaint of dyspnea and weakness with the following vitals: BP 72/64, HR 112, RR 40, SpO2 82%, temp. 99.1°F. He is on 6 L/minute of oxygen via nasal cannula. The ECG shows sinus tachycardia with frequent PVCs. ABG reveals: pH 7.28, pCO2 68, HCO3 24. pO2 58. Physical exam reveals profound vesicular rales and bronchial wheezing. Your most likely diagnosis is
A. CHF; uncompensated respiratory acidosis, hypoxemia
B. Adult respiratory distress syndrome; compensated metabolic acidosis, hypoxemia
C. Status asthmaticus; uncompensated metabolic acidosis, hypoxemia
D. Cardiogenic shock; uncompensated respiratory acidosis, hypoxemia
- D: Cardiogenic shock with uncompensated respiratory acidosis and hypoxemia. The hypotension indicates cardiogenic shock secondary to pump failure, leading to left ventricular heart failure (vesicular rales and hypoxia). The pH is low and the pCO2 is high, resulting in respiratory acidosis. The HCO3 is normal, indicating that no compensatory response has occurred. Acute respiratory failure is defined as a pO2 50 mmHg. Normal pO2 is 80-100 mmHg.
- You are transporting a twenty-four-year-old trauma patient from a rural facility who has just been given Anectine in preparation for endotracheal intubation. The patient’s heart rate increases, muscle rigidity is present, and you observe that his end-tidal CO2 has increased to 60 mmHg. Your next intervention would be to administer
A. Midazolam
B. Sodium Bicarbonate
C. Dantrolene
D. Glucagon
- C: Malignant hyperthermia is a rare life-threatening condition that is triggered by certain medications administered during general anesthesia (gas agents) and the neuromuscular blocking agent succinylcholine (anectine). Dantrolene sodium is classified as a muscle relaxant and is the only specific and effective treatment of malignant hyperthermia.
- When performing a needle thoracostomy, which of the following is generally the preferred site?
A. 2nd intercostal space, anterior-axillary line
B. 5th intercostal space, anterior-midaxillary line
C. 4th intercostal space, midclavicular line
D. 2nd intercostal space, midclavicular line
- D: To release intrapleural pressure (tension pneumothorax), a large-bore needle should be placed into the pleural space. The second intercostal space, midclavicular approach is generally preferred. An alternate site approach is the fourth or fifth intercostal anterior midaxillary line. The anterior site is used to avoid the internal mammary vessels.
- Your patient presents with ABG’s of pH 7.39, pCO2 68 HCO3 32, pO2 82. He has history of COPD and weighs 65 kg. He presents with a history of SOB for 3 days with a RR 20 and is on 4 L/minute of oxygen by NC. He speaks in four- to five-word sentences. What acid-base disorder is present?
A. Metabolic acidosis with partial compensation
B. Respiratory acidosis with complete compensation
C. Metabolic alkalosis with no compensation
D. Respiratory alkalosis with no compensation
- B: Respiratory acidosis with complete compensation. The pCO2 is elevated, which is the primary disorder, and the compensatory response is the increased HCO3. The pH is normal, so there is complete compensation.
- Hamman’s sign may indicate which of the following?
A. Tension pneumothorax
B. Tracheobronchial injury
C. Aortic rupture
D. Cardiac tamponade
- B: Hamman’s sign is a crunching sound heard with auscultation and may be synchronized with the patient’s heart beat. This sign is associated with tracheobronchial injury.
- ABG reveals pH 7.41, pCO2 38, HCO3 22, pO2 56 of a 70-kg patient on a ventilator with the following settings: Vt 700, F 14, FIO2 0.5, I:E 1:2, PIP 46, Pplat 40, and PEEP 5. How will you manage this patient?
A. Increase FIO2
B. Increase PEEP
C. Decrease Vt
D. All of the above
- A: The pCO2 is
- When managing pO2 of <60, you would
A. Increase FIO2 and apply/or increase PEEP
B. Increase Vt and apply/or increase PEEP
C. Increase FIO2
D. Increase Vt
- A: The FIO2 can be increased and/or application of/or increasing PEEP can also provide acceptable oxygenation levels.
- The patient you are transporting reveals the following ABG: pH 7.51, pCO2 28, HCO3 24, pO2 110. He is a 60-kg male patient with Vt 650, F14, FIO20.21, I:E 1:2, PIP 46, Pplat 42, and PEEP 0. What is your ABG interpretation, and how will you correct it?
A. Respiratory acidosis; increase respiratory rate (F)
B. Respiratory alkalosis; decrease Vt
C. Metabolic alkalosis; increase FIO2
D. Respiratory alkalosis; increase PEEP
- B: The pCO2 is decreased and the pH is increased, indicating a respiratory alkalosis. The HCO3 is normal, indicating there is no compensation.
- Minute ventilation is
A. RR × weight in kg
B. RR × SPO2
C. Vt × weight in kg
D. Vt × RR
- D: Tidal volume times the respiratory rate equal minute ventilation. The formula is known as VE = Vt × f. VE signifies minute ventilation; Vt signifies tidal volume and f signifies respiratory rate.
- High-pressure alarms can be caused by all of the following, except
A. Hypovolemia
B. Connections
C. Pneumothorax
D. Obstructions
- A: Mechanical ventilatory complications most commonly encountered in the emergency department and during transport include hypoxia, hypotension, high-pressure alarms, and low exhaled volume alarms.
- Low-pressure alarms can be caused by all of the following, except
A. Hypovolemia
B. Leaks in ventilator tubing
C. Pneumothorax
D. Connections
- C: Pneumothorax can trigger high-pressure alarms when resistance to ventilation is too high.
- Vt is calculated at
A. 3-5 mL/kg
B. 5-8 mL/kg
C. 6-10 mL/kg
D. 10-15 mL/kg
- B: Vt (tidal volume) of 5-8 mL/kg is generally indicated, with the lowest values recommended in the presence of obstructive airway disease and ARDS. The goal is to adjust the TV so that plateau pressures are less than 35 cm H2O.
- The test most often used to diagnose a pulmonary embolism is
A. Chest x-ray
B. V/Q lung scan
C. 12-lead ECG
D. ABG
- B: A ventilation/perfusion lung scan, also known as a V/Q lung scan, is a type of medical imaging that is used to evaluate the circulation of air and blood within the lungs. The ventilation portion of the exam assesses the ability of air to reach all sections of the lungs, and the perfusion portion evaluates how well blood circulates within the lungs. The test is commonly done to evaluate for the presence of blood clots or abnormal blood flow inside the lungs, such as a pulmonary embolism (PE).
- Acute respiratory failure is defined as
A. pO2 <60 mmHg and pCO2 >50
B. pO2 <80 mmHg and pCO2 >60
C. pO2 <60 mmHg and pCO2 >30
D. pO2 <90 mmHg and pCO2 >50
- A: Acute respiratory failure (ARF) exists when breathing fails in its ability to maintain arterial blood gases within a normal range. By definition, ARF is present when the blood gases demonstrate a pO2 < 60 mmHg (hypoxic respiratory failure) and a pCO2 > 50 mmHg (ventilatory respiratory failure), which is usually accompanied by fall in the pH < 7.3.
- Situations that involve a left shift in the oxygen-hemoglobin dissociation curve are all of the following, except
A. Alkalosis
B. Hypocapnia
C. Hypothermia
D. Increased levels of 2,3-DPG
- D: The oxyhemoglobin dissociation curve describes the relation between the partial pressure of oxygen and the oxygen saturation. The effectiveness of hemoglobin-oxygen binding can be affected by several factors.
- Situations that involve a right shift in the oxygen-hemoglobin dissociation curve are all of the following, except
A. Alkalosis
B. Hypercapnia
C. Hyperthermia
D. Increased level of 2,3-DPG
- A: Alkalosis causes a left shift.
- Repeated doses of etomidate can cause
A. Increased ICP
B. Acute adrenal insufficiency
C. AMI
D. Pulmonary edema
- B: The use of etomidate for continued sedation of critically ill patients has been associated with increased mortality, which is due to suppression of steroid synthesis (both glucocorticoids and mineralocorticoids) in the adrenal cortex, which sometimes leads to death due to an adrenal crisis. There is no evidence that a single induction dose of etomidate has any effect on morbidity or mortality.
- Interpret the following blood gas: pH 7.39, HCO3 18, pCO2 31.
A. Respiratory alkalosis; completely compensated
B. Respiratory acidosis; partially compensated
C. Metabolic acidosis; partially compensated
D. Metabolic acidosis; completely compensated
- D: The pH is normal, HCO3 is low (acidosis), and the pCO2 is low (alkalosis). When both HCO3 and pCO2 are turned in opposite directions, the etiology is usually metabolic. The primary mechanism is a metabolic acidosis that has been fully compensated by respiratory alkalosis, making the pH within normal range.
- You are transporting a forty-year-old man from a rural ICU. The CXR reveals a ground glass appearance. The patient is on a ventilator with settings at: Vt 900 mL, rate of 16, FIO2 0.8 with a PEEP of 5. ABG’s reveal: pH 7.34, pO2 76, pCO2 38 and HCO3 of 24. What pulmonary condition do you suspect?
A. Pneumothorax
B. Pulmonary edema
C. ARDS
D. Cor pulmonale
- C: ARDS, also known as respiratory distress syndrome (RDS); lungs are typically irregularly inflamed and highly vulnerable to atelectasis as well as barotrauma and volutrauma, which leads to impaired gas change, resulting in a severe oxygenation defect (hypoxemia). Their compliance is typically reduced, and their dead space increased. ARDS has gradually shifted to mean acute rather than adult. A less severe form is called acute lung injury (ALI).
- You would manage the above patient by
A. Increasing the rate
B. Increasing PEEP
C. Performing a rapid needle decompression
D. Administering Lasix
- B: Positive end-expiratory pressure (PEEP) is used in mechanically- ventilated patients with ARDS to improve oxygenation.
- The MD has ordered a BNP, which would evaluate the patient for
A. Sepsis
B. Hypovolemia
C. Right ventricular MI
D. CHF
- D: BNP is an amino acid polypeptide released by the ventricles of the heart in response to excessive stretching of the heart muscle cells. BNP is a blood test used to help in the diagnosis of CHF and is typically higher in these patients. For patients with CHF, the BNP levels will generally be >100 pg/mL. The synthetic version of BNP in medication form is Neseritide (natracor), which reduces systemic vascular resistance and cardiac output.
- Which of the following paralytics stimulates motor end plate acetylcholine receptors causing persistent depolarization?
A. Succinylcholine
B. Rocuronium
C. Vecuronium
D. Pancuronium
- A: Neuromuscular blocking agents (NMBA) binds with cholinergic receptor sites of motor neurons preventing the neurotransmitter from relaying the signal. The interruption in this signal pathway is what causes paralysis. Succinylcholine (anectine) is classified as a noncompetitive depolarizing agent because it binds with the motor end-plate receptor site, causing a continuous depolarization to take place. It is this depolarization that causes the initial fasciculations (irregular muscle contractions produced by depolarization of the muscle membrane before complete cessation of muscle activity). As the acetycholinesterase enzyme breaks down the NMBA, there is a return of fasciculations.
- When administering a defasciculating neuromuscular blockade, the dose recommended is
A. 5% normal RSI dosage of NMBA
B. 10% normal RSI dosage of NMBA
C. 15% normal RSI dosage of NMBA
D. 20% normal RSI dosage of NMBA
- B: The administration of a defasiculation dose of a competitivenon depolarizing NMBA, such as vecuronium (Norcuron), can prevent fasciculations that occur when succinylcholine (Anectine) is administered. Administration of 10% of the initial NMBA dose is recommended to prevent this complication, especially in trauma patients who have sustained significant skeletal fractures for the purpose of preventing further injury at the fracture site/s.
- You are transporting a twenty-five-year-old woman with a history of suspected overdose. The following ABGs were obtained prior to your arrival at the sending facility: pH 7.52, pCO2 27, HCO3 24, pO2 110. You would most likely suspect
A. Narcotic overdose
B. TCA overdose
C. Early salicylate poisoning
D. Insulin overdose
- C: The ABG interpretation of a pH 7.52, pCO2 27 and HCO3 24 is a noncompensated respiratory alkalosis, which is present is early salicylate poisoning. The metabolic changes eventually lead to renal depletion of fluids and electrolytes, hypoglycemia, hypokalemia, and a mixed presentation of respiratory and metabolic alkalosis coupled with metabolic acidosis, which may provoke cardiac dysrhythmias, acute pulmonary edema, renal failure or neurological injury. The clinical presentation of salicylate poisoning can also include gastrointestinal bleeding and an unexplained elevated anion gap (metabolic acidosis). Salicylate levels are obtained four to six hours after ingestion. Earlier samples may be unreliable because the pharmacokinetics is not stable before that time. The most important information in assessing severity, however is the patient’s clinical condition.
- If the PIP does not change on a ventilator patient with respiratory acidosis, always
A. Increase Vt before rate
B. Decrease Vt before rate
C. Increase rate before Vt
D. Decrease rate before Vt
- B: Elevated peak inspiratory pressures (PIP) can be managed by decreasing the flow rate and tidal volume initially. If necessary, increasing the respiratory rate can be done to correct an underlying respiratory acidosis.
- Trouble-shooting high-pressure alarms on the ventilator can be caused by all of the following, except
A. Secretions
B. Obstructions
C. ET tube main-stem placement
D. Leak in ventilator tubing
- D: Leaks and/or loose connections are associated with low ventilator alarms. Refer to the tables in questions 19 and 20 for review.
- An elevated anion gap can indicate the presence of which of the following?
A. Respiratory acidosis
B. Respiratory alkalosis
C. Metabolic acidosis
D. Metabolic alkalosis
- C: An elevated anion gap is associated with metabolic acidosis. Refer to the table in question 1 for review of causes for elevated anion gap.
- The average endotracheal tube size that should be utilized in an adult male patient is
A. 6.0
B. 7.0
C. 8.0
D. 9.0
- C: The average recommended ET tube for an adult male airway is 8.0-9.0 mm (size refers to the internal diameter of the tube). The average adult female airway can accommodate a 7.0-8.0-mm tube. The balloon cuff pressure should be at minimal occluding volume of 5-10 mL. At pressures greater than 25 mmHg, mucosal ischemia begins to occur.
- The administration of Succinylcholine is contraindicated in which of the following?
A. Hypoglycemia
B. Hyperkalemia
C. Hypercalemia
D. Hypernatremia
- B: The administration of succinylcholine (Anectine) is contraindicated in patients with known and/or suspected hyperkalemia. The hyperkalemia associated with succinylcholine, which can approach or exceed life-threatening levels, is of greater consequence in patients who have a history of burns or massive muscle trauma 2 to 3 days prior, and patients may continue to be at risk for hyperkalemia for 2 to 3 months. The two absolute contraindications to use of succinylcholine are situations in which cricothyrotomy would be difficult or impossible to accomplish and the use of the medication by individuals who do not possess a thorough knowledge about the pharmacology of neuromuscular blocking agents, and they do not possess advanced airway skills or an alternative plan if they should encounter a failed airway.
- Midazolam is classified as a
A. Narcotic analgesic
B. Hallucinogen
C. Benzodiazepine
D. Nondepolarizing paralytic
- C: Midazolam (versed) is classified as a benzodiazepine, schedule II controlled drug. It has potent anxiolytic, amnestic, hypnotic, anticonvulsant, skeletal muscle relaxant, and sedative properties. Major adverse effects include hypotension and respiratory depression and/or arrest. Flumazenil is a benzodiazepine antagonist that can be used to treat an overdose as well to reverse sedation. Lopez, Orchid Lee (2011-02-15). Back To Basics: Critical Care Transport Certification Review (p. 172). Xlibris. Kindle Edition.
- Ketamine administration is considered the drug of choice for a patient presenting with which of the following?
A. Head injury
B. Seizure
C. Asthma
D. Burns
- C: Ketamine (ketalar) is classified as an NMDA receptor antagonist with a wide range of effects that include analgesia, anesthesia, hallucinations, elevated blood pressure, and bronchodilation. Indications include use for pediatric anesthesia and asthmatics or patients with COPD. Ketamine has been useful in managing bronchospasm because it inhibits pro-inflammatory cytokines. The accumulation of pro-inflammatory cytokines causes beta-adrenergic receptor hypofunction.
- Management of an intubated patient presenting with a diagnosis of ARDS would include
A. Application of positive end-expiratory pressure
B. Application of higher than normal tidal volumes
C. Decreasing ventilation rate
D. Administration of Magnesium Sulfate
- A: Application of positive end-expiratory pressure (PEEP). ARDS lungs are typically irregularly inflamed and highly vulnerable to atelectasis as well as barotrauma and volutrauma. Their compliance is typically reduced, and their dead space is increased. Initiating ventilation of patients with ARDS with A/C ventilation at a tidal volume of 6 mL/kg, with a PEEP of 5 and initial ventilatory rate of 12, titrated up to maintain a pH > 7.25. Target plateau pressure of
- Excess of mucous secretions and chronic inflammation of the bronchi, leading to obstruction of airflow, hypoxemia, and hypercapnea best describes which of the following conditions?
A. Emphysema
B. Chronic bronchitis
C. Asthma
D. Pneumonia
- B: Chronic obstructive pulmonary disease (COPD) can be considered a continuum with asthma on one end, chronic bronchitis in the middle, and emphysema on the opposite end. It is not unusual for emphysema and chronic bronchitis to coexist in varying degrees. Physical examination may reveal pursed-lip breathing, flaring nostrils, rhonchi and/or expiratory wheezes, hyperresonant to percussion, anterior-posterior diameter of the chest is increased (barrel-chest), and tachycardia. The patient’s mental status is an important component since this is the first sign showing that CO2 level has increased beyond the patient’s normal baseline level. Chronic bronchitis results in mucus-secreting cells of the bronchial walls hypersecreting copious amounts of sputum, which prevents airflow into the alveoli. The alveolar gas exchange is normal, but the alveoli are under-ventilated because of obstruction of airflow. Refer the following tables for review of diagnostic studies, pathophysiology, and management of the COPD patient.
- A chronic obstructive pulmonary disease (COPD) patient would most likely present with which of the following x-ray findings?
A. Hyperinflation of the lungs, narrow and elongated heart shadow, increased anterior-posterior diameter of the chest
B. Widespread pulmonary infiltrates, ground-glassy appearance
C. Lobar infiltrates and consolidation
D. Cardiomegaly and pulmonary vascular congestion
- A: Hyperinflation of the lungs, narrow elongated heart shadow, increased anterior-posterior diameter, and flattened hemidiaphragms are common findings on the chest radiography of a COPD patient. ARDS can present with widespread infilitrates, with a ground glassy appearance, pneumonia with lobar infiltrates and consolidation, and CHF with cardiomegaly and pulmonary congestion.
- The diagnosis of ARDS would most likely present with which of the following x-ray findings?
A. Hyperinflation of the lungs, narrow and elongated heart shadow, increased anterior-posterior diameter of the chest
B. Widespread pulmonary infiltrates, ground-glassy appearance
C. Lobar infiltrates and consolidation
D. Cardiomegaly and pulmonary vascular congestion
- B: Widespread pulmonary infiltrates that is ground glassy in appearance. ARDS results from a severe alteration in pulmonary vascular permeability, which leads to a change in the lung structure and function. The outstanding characteristic is hypoxemia refractory to oxygen therapy. ARDS is most commonly seen in patients with direct or indirect acute lung injury. Because ARDS is a complication of other illnesses or injuries, the transport team must also consider the pathophysiology of the underlying problem.
- An ominous sign of impending acute respiratory failure in the asthma patient would most likely be which of the following?
A. Increased respiratory rate
B. Increased bronchoconstriction
C. Decreased or absence of bronchoconstriction
D. Increased intercostal retractions
- C: Absence of wheezing may indicate that the patient is not able to ventilate sufficiently to produce breath sounds. The problem with a patient presenting with asthma is a prolonged expiratory phase, which can cause air trapping. These patients are not able to exhale adequately. The physical examination can reveal different degrees of respiratory distress based on the severity of their condition. The transport team should consider the situation emergent if an asthma patient presents in respiratory distress without wheezing and has difficulty in speaking. Acute respiratory failure is defined as a pO2 50 mmHg.
- Signs and symptoms for a patient presenting with a tension pneumothorax would include all of the following, except
A. Tachycardia
B. Increased work of breathing
C. Narrowing pulse pressure
D. Widening pulse pressure
- D: Perfusion becomes inadequate because of decreased venous return to the heart as a result of the increased intrapleural pressure and shift of mediastinal structures. A narrowing pulse pressure is considered a compensatory response that can occur just prior to the patient becoming hypotensive. The diastolic blood pressure becomes closer to the systolic blood pressure in a narrowing pulse pressure, whereas, the systolic blood pressure increases in a widening pulse pressure as seen with Cushing’s triad (increased intracranial pressure[ICP]).
- The normal range for pCO2 when evaluating an arterial blood gas is
A. 30-40 mmHg
B. 35-45 mmHg
C. 40-50 mmHg
D. 50-60 mmHg
- B: Normal range pCO2 is 35-45 mmHg.
- The normal range for pH when evaluating an arterial blood gas is
A. 7.15-7.25
B. 7.25-7.35
C. 7.35-7.45
D. 7.45-7.55
- C: Normal range pH is 7.35-7.45.
- The normal range for HCO3 when evaluating an arterial blood gas is
A. 16-20 mEq/L
B. 19-22 mEq/L
C. 22-26 mEq/L
D. 25-30 mEq/L
- C: Normal range HCO3 is 22-26.
- The most likely causes of metabolic alkalosis can include all of the following, except
A. Vomiting
B. NG suctioning
C. Diarrhea
D. Diuretics
- C: Diarrheal dehydration can cause metabolic acidosis, especially in the pediatric patient. Metabolic alkalosis can be caused by loss of hydrogen ions through the kidneys or GI tract. Vomiting or nasogastric (NG) suction generates metabolic alkalosis by the loss of gastric secretions, which are rich in hydrochloric acid (HCL). Renal losses (use of diuretics) of hydrogen ions occur when the distal delivery of sodium increases in the presence of excess aldosterone, resulting in reabsorption of sodium, leading to the secretion of hydrogen ions and potassium ions. The administration of sodium bicarbonate in amounts that exceed the capacity of the kidneys to excrete this excess bicarbonate may cause metabolic alkalosis. Shifting of hydrogen ions into the intracellular space can also occur, which is mainly seen with hypokalemia.
ABG - Normal range pH pCO2 HCO3 pO2
ABG Normal range pH 7.35-7.45 pCO2 35-45 HCO3 22-26 pO2 80-100
The five simple rules to ABG interpretation.
- Evaluate pH. Is it normal?
- Evaluate the pCO2. Is it acute or chronic for respiratory disorder?
- Evaluate the HCO3 and calculate the anion gap [Na+] - ([Cl-] + [HCO3-]) for metabolic disorder or delta gap. Check if metabolic acidosis is present.
- Identify the primary disorder.
- Determine if compensation is present and the degree of compensation using Winter’s formula. Is there more than one disorder?
pH
Acidosis < 7.35 - 7.45 > Alkalosis
pCO2
Alkalosis < 35 - 45 > Acidosis
Indications for chest tube placement may include
-drainage of hemothorax or large pleural effusion drainage -large pneumothorax (greater than 25%) -prophylactic placement of chest tubes in a patient, with suspected chest trauma before transport to specialized trauma center -flail chest segment requiring ventilator support and severe pulmonary contusion with effusion
Stages of Shock - Vol. of blood loss - Physiological Class I - Early, reversible, compensatory shock
<750ml) Mild increase in HR & RR
Lung Volumes:
Tidal volume
- Volume of air inspired or expired with each normal breath.
- Amount 500 mL, which is approximately 5-8 mL/kg.
Lung Volumes:
Inspiratory reserve volume
- Extra volume of air that can be inspired above normal tidal volume.
- Amount 3 liters.
Lung Volumes:
Expiratory reserve volume
- Extra volume of air that can be expired by forceful expiration after the end of a normal tidal expiration.
- Amount 1,100 mL.
Lung Volumes:
Dead-space volume
- The amount of gas in the tidal volume that remains in the air passageways unavailable for gas exchange.
- Anatomic dead space includes the trachea and bronchi. Physiologic dead space from COPD, obstruction, or atelactesis.
- Amount 150 mL.
Lung capacities (Combination of lung volumes)
Inspiratory capacity
- TV + IRV
- The amount of air a person can breathe beginning at the normal expiratory level and distending the lungs to maximum capacity
- Approx. 3,500 mL
Lung capacities (Combination of lung volumes)
Functional residual capacity (FRC)
- ERV + RV
- The amount of air that remains in the lungs at the end of normal expiration
Lung capacities (Combination of lung volumes)
Vital capacity
- IRV + TV
- The amount of air a person can expel from the lungs after first filling the lungs to their maximum extent and then expiring to the maximum extent.
Lung capacities (Combination of lung volumes)
Total lung capacity
- VC + RV
- The maximum volume to which the lungs can be expanded with the greatest possible inspiratory effort.
Oxyhemoglobin diassociation curve:
Right Shift
Causes a decrease in the affinity of hemoglobin to oxygen. This makes it harder for hemoglobin to bind to oxygen, but it makes it easier for hemoglobin to release bound oxygen.
R stands for Raised/Releases Oxygen
- High temperature (hyperthermia)
- High 2,3-DPG levels Production increases with hypoxemia, chronic lung disease, anemia, and CHF
- High pCO2
Oxyhemoglobin diassociation curve:
Left Shift
Causes an increase in the affinity, making the oxygen easier for hemoglobin to pick up but harder to release.
L stands for Low/Holds onto Oxygen - There’s an L in Alkalosis
- Low temperature (hypothermia)
- Low 2,3-DPG levels Production decreases with septic shock and hypophosphatemia
- Low pCO2
- lungs are typically irregularly inflamed and highly vulnerable to atelectasis as well as barotrauma and volutrauma, which leads to impaired gas change, resulting in a severe oxygenation defect (hypoxemia).
- Their compliance is typically reduced, and their dead space increased.
- If PaO2:FIO2 < 300 mmHg (40 kPa) acute lung injury (ALI) is considered to be present.
- If PaO2:FIO2 < 200 mmHg (26.7 kPa), ARDS is considered to be present.
