Intern Boot Camp Dyspnea

Intern Boot Camp Abdominal Pain

Intern Boot CampDyspneaJoshua Sapkin, MDAssociate Program DirectorLAC+USC Internal Medicine Residency ProgramLecture GoalsReview the various etiologies of dyspnea by organ systemReview the most common cardiac and pulmonary etiologies of hypoxiaUtilize the A:a gradient to determine the correct pathophysiology responsible for a patients hypoxiaAppreciate the systematic approach that should be taken to evaluate a dyspneic patientAppreciate the roles, including limitations, of various diagnostic tests

EtiologiesCardiacPulmonaryMixed cardiac and pulmonaryPsychiatric (e.g. anxiety, panic disorder)Cardiac EtiologiesCongestive heart failureSystolic dysfunctionDiastolic dysfunctionValvular heart diseaseHypertrophic obstructive cardiomyopathyCardiac tamponadeTension pneumothoraxIntracardiac right to left shuntingArrhythmiasBradydarrhythmiasTachyarrhythmias

Pulmonary EtiologiesV/Q mismatchShuntDiffusion barrierHypoventilationAltitudeV/Q MismatchThe most common pathophysiology leading to hypoxemia.AtelectasisChronic bronchitisPneumonitisPneumothoraxPleural effusionPulmonary edemaShuntPulmonary embolusAcute lung injuryARDSHepatopulmonary syndromeRight to left intracardiac shuntsHypoventilationOpiate analgesicsBenzodiazepinesBarbituratesAsthmaEmphysemaCentral disorders

Diffusion BarriersInterstitial lung diseaseMedication induced, e.g. nitrofurantoin, sulfasalazine, amiodarone, Illicit drugs, e.g. heroinCryptogenic organizing pneumoniaLymphocytic interstitial pneumoniaNon-specific interstitial pneumonitisLymphangioleiomyomatosisConnective tissue diseaseSarcoidosisInfectiousHypersensitivity pneumonitisOther EtiologiesSevere kyphoscoliosisNeuromuscular disorders, e.g. myasthenia gravisAltitudeCarbon monoxide poisoningSevere anemia (usually fairly acute)Question 1Which of the pathophysiologies responsible for dyspnea is not associated with an increased A:a gradient:V/Q mismatch Shunt Diffusion barrier HypoventilationAlveolar:arterial gradientA-a gradient = predicted pO2 observed PO2

PAO2 = (FIO2 X 713) (PaCO2/0.8) at sea level

PAO2 = 150-(PaCO2/0.8) at sea level on room air

Poor mans A:a gradient (ABG must be performed on room air): 140-pCO2-pO2Normal= {Age 4} 4 Case 1The nurse calls you because your patient who had a left subclavian central venous catheter placed 1 hour ago is complaining of shortness of breath. The patient is a 55 year old man who was admitted for left leg cellulitis that was refractory to oral antibiotics.Case 1Which of the following diagnoses is most likely?A. Pneumocystis Jaroveci pneumoniaB. Pulmonary embolusC. Intrapulmonary hemorrhageD. Pneumothorax

Case 1Upon arriving at the patients bedside, you find him in mild respiratory distress.Vital signs: Blood Pressure: 144/82. Heart rate 100. Respirations: 24. Temperature: 98.2. Oxygen saturation 94% on room air.P.E. HEENT: Anicteric. No conjunctival pallor. Neck: No JVD.Cardiac: Tachycardic.Chest: Trachea midline. Lungs clear to auscultationAbdomen: Non-tender, non-distended. No organomegaly.Be careful of the pulse oximeter

Case 1What is the next best step in the management of this patient?A. Chest X-rayB. V/Q scanC. HRCT of the lungsD. EchocardiogramCase 1

Case 1Why are vital signs called vital signs?They are a necessary component of the medical documentation in order to bill health insurances (vital for reimbursement)They are important clues to the patients diagnosis (vital for establishing a diagnosis).The nurses consider them essential pieces of information before paging a physician (vital for paging a physician)They reflect physiologic processes that are essential to sustaining life.

Case 1All of the following measures would be appropriate a this time EXCEPT:A. Check the patients blood pressure in the supine and sitting position.B. Ensure the patient has two large bore peripheral IV sites.C. Contact the GI fellow who performed the procedure.D. STAT General Surgery consultE. Ask the nurse if he/she would like to join you for a drink at Barbaras Brewery after work. Case 1

Case 2The nurse pages you because your patient has a respiratory rate of 6 and an oxygen saturation of 85% on room air. He is a 42 year-old man with history of IVDU who was admitted for multiple abscesses and cellulitis affecting both upper extremities. He had been off the ward for 3 hours. His nurse noticed that he seemed under the influence of a substance upon returning to his room about 1 hour ago.

P.E.Height: 5 9 Weight: 140 lbs. Vital Signs: Blood pressure: 100/62. Heart Rate: 110 Respirations: 6. Temperature: 99.0. Pulse oximeter 85% on room air.

General: The patient does not respond to verbal or painful stimuli. HEENT: Pinpoint pupils. Sluggish response to light. There is dried food at the borders of the mouth.Neck: No JVD.Tachycardic . No murmurs, rubs or gallops.Chest: No deformities. There are decreased breath sounds over the right lower lung field.

Case 2The next best step in the management of this patient is:A. Naloxone intravenouslyB. Sternal rubC. Call the airway teamD. Ventilate the patient using a bag valve mask (BVM).Case 2The ABG prior to hyperventilating the patient revealed the following:7.58/60/58/24/85%

What is the calculated A:a gradient?

What is the expected calculated A:a gradient?Case 2What is the calculated A:a gradient?140-pCO2-pO2 = 140-60-58=22

What is the expected calculated A:a gradient?Age 42: [424] 4= 14

Case 2

Case 3 A 67 year-old woman is found to have an oxygen saturation of 88% by her nurse 4 days after undergoing bilateral total knee arthroplasties. Vital Signs: BP 120/72. Pulse 100. Respirations 20. Temperature 99.4. Exam is significant for inspiratory rales over bilateral bases. ABG: 7.46/35/64/20/88%Case 3Which piece of data provides the best evidence that this woman does not have a partial small bowel obstruction?A. Her cholecystectomy was performed 20 years ago.B. The timing and duration of her symptomsC. The results of her abdominal seriesD. Her abdominal examCase 3

Case 3Which of the following statements is true regarding pulmonary emboli?A. V/Q scan is the gold standard for establishing this condition.B. A confirmatory CT angiogram should be performed before starting anticoagulation.C. The D-dimer test is a highly sensitive and specific test for this condition.D. The ECG usually demonstrates evidence of right heart strain during an acute pulmonary embolus.Case 4A 75 year old woman with essential hypertension left ventricular hypertrophy (hypertensive heart disease), diabetes and long history of smoking undergoes surgical repair of a 7 cm aneurysm of the descending aorta. She develops hypoxia on post-operative day #1 requiring 4 liters of oxygen via nasal cannula to maintain her oxygen saturations above 90%. Exam is significant for elevated jugulovenous pressure, scattered expiratory wheezes, decreased breath sounds over the bases and 1+ pitting edema over bilateral lower extremities. Case 4Which piece of history is most pertinent to establishing the cause of her hypoxia?A. Her net fluid intake/output over the past 24 hours.B. The number of pack-years she has smoked in her lifetime.C. The length of the surgery.D. The total amount of opiate analgesics administered since surgery.Case 4All of the following diagnostics can help distinguish between a pulmonary and cardiac cause of dyspnea EXCEPT:A. B type natriuretic peptideB. Chest x-rayC. Oxygen Extraction Ratio VO2/DO2 x 100 D. Pulmonary capillary wedge pressure