5/24/14. A Dusky Hypoxic Woman. Blue man case #1. Blue woman case #2

Transcription

1 A Dusky Hypoxic Woman Craig Smollin MD Associate Medical Director California Poison Control Center - SF Division Assistant Professor of Emergency Medicine - UCSF Blue man case #1 A 46 year-old male was sent to the emergency department for cyanosis. In the emergency department he appeared in no acute distress and had obvious blue-gray discoloration of the skin. Vital signs were BP 148/81, P 88, RR 16, O2 sat 98%, Temp afebrile. The rest of the exam is unremarkable. Blue woman case #2 A 34 year old HIV+ woman presents with c/o feeling lightheaded, nauseated, and short of breath. Vital signs were BP 124/88, P 116, RR 18, O2 sat 82% NRB, Afebrile. She was in no respiratory distress but appeared to have blue discoloration of the lips, gums, face and peripherally in the digits and nail beds. The rest of the exam was unremarkable. 1

2 What is cyanosis? Blue discoloration due to hypoxemia. Central vs. peripheral First visible on lips and tongue. Deoxygenated hgb = 3.5 g/dl in arterial blood. O2 sat 73-78% Cyanosis is an unreliable sign of hypoxemia. Significant hypoxemia can be present without cyanosis Significant hypoxemia can be present without cyanosis Significant hypoxemia can be present without cyanosis 2

3 Approach to the blue patient Blue man case #1 A 46 year-old male was sent to the emergency department for cyanosis. In the emergency department he appeared in no acute distress and had obvious blue-gray discoloration of the skin. Vital signs were BP 148/81, P 88, RR 16, O2 sat 98%, Temp afebrile. The rest of the exam is unremarkable. Blue man case #1 A 46 year-old male was sent to the emergency department for cyanosis. In the emergency department he appeared in no acute distress and had obvious blue-gray discoloration of the skin. Vital signs were BP 148/81, P 88, RR 16, O2 sat 98%, Temp afebrile. The rest of the exam is unremarkable. ABG: 7.45, PCO2 35, PO2 133, lactate 1.8 What is the diagnosis? 3

4 Blue man case #1 A 46 year-old male was sent to the emergency department for cyanosis. In the emergency department he appeared in no acute distress and had obvious blue-gray discoloration of the skin. Vital signs were BP 148/81, P 88, RR 16, O2 sat 98%, Temp afebrile. The rest of the exam is unremarkable. ABG: 7.45, PCO2 35, PO2 133, lactate 1.8 What is the diagnosis? Approach to the blue patient Blue man case #1 On further questions the patient admits to the use of colloidal silver for the treatment of chronic MRSA infection of the skin. He purchased the product over the internet and has been using it regularly over the past year. During that time, he has noticed a gradual change in his skin color to the current blue-gray appearance. 4

5 Argyria Blue man case #2 A 34 year old HIV+ woman presents with c/o feeling lightheaded, nauseated, and short of breath. Vital signs were BP 124/88, P 116, RR 18, O2 sat 82% NRB, Afebrile. She was in no respiratory distress but appeared cyanotic in the lips, gums, face and peripherally in the digits and nail beds. The rest of the exam was unremarkable. Blue man case #2 A 34 year old HIV+ woman presents with c/o feeling lightheaded, nauseated, and short of breath. Vital signs were BP 124/88, P 116, RR 18, O2 sat 82% NRB, Afebrile. She was in no respiratory distress but appeared cyanotic in the lips, gums, face and peripherally in the digits and nail beds. The rest of the exam was unremarkable. ABG = 7.44, PCO2 31, PO2 307, Lactate 1.0 5

6 Blue man case #2 A 34 year old HIV+ woman presents with c/o feeling lightheaded, nauseated, and short of breath. Vital signs were BP 124/88, P 116, RR 18, O2 sat 82% NRB, Afebrile. She was in no respiratory distress but appeared cyanotic in the lips, gums, face and peripherally in the digits and nail beds. The rest of the exam was unremarkable. ABG = 7.44, PCO2 31, PO2 307, Lactate 1.0 Approach to the blue patient Blue man case #2 A 34 year old HIV+ woman presents with c/o feeling lightheaded, nauseated, and short of breath. Vital signs were BP 124/88, P 116, RR 18, O2 sat 82% NRB, Afebrile. She was in no respiratory distress but appeared cyanotic in the lips, gums, face and peripherally in the digits and nail beds. The rest of the exam was unremarkable. ABG = 7.44, PCO2 31, PO2 307, Lactate 1.0 MetHb = 41% 6

7 Common drugs and toxins causing methgb Drugs Local anesthetics Chloroquin Dapsone Metaclopramide Nitrites Phenazopyridine Primaquin Sulfamethoxazole Toxins Aniline dyes Benzene derivatives Nitrates or nitrites in food or well water Paraquat Common drugs and toxins causing methgb Drugs Local anesthetics Chloroquin Dapsone Metaclopramide Nitrites Phenazopyridine Primaquin Sulfamethoxazole Toxins Aniline dyes Benzene derivatives Nitrates or nitrites in food or well water Paraquat Methemaglobin level = 44.9% 7

8 Met-hgb Pathophysiology Fe 2+ Hemoglobin Hemoglobin 8

9 Oxygen Fe 2+ Hemoglobin Fe 2+ Fe 3+ Met-Hgb 1. Functional Anemia 9

10 100 Percent Saturation Hgb Shift in Oxygen Hgb Dissociation Curve Oxygen Partial Pressure (mmhg) Percent Saturation Hgb 50 Percent Saturation Hgb 50 alveoli tissues alveoli Oxygen Partial Pressure (mmhg) Oxygen Partial Pressure (mmhg) 10

11 Percent Saturation Hgb 50 Percent Saturation Hgb 50 tissues alveoli tissues alveoli Oxygen Partial Pressure (mmhg) Oxygen Partial Pressure (mmhg) Percent Saturation Hgb 50 Percent Saturation Hgb 50 tissues alveoli tissues alveoli Oxygen Partial Pressure (mmhg) Oxygen Partial Pressure (mmhg) 11

12 Met-Hgb Pathophysiology Symptoms and Signs Hemoglobin Fe oxidized to Fe3+ Functional anemia Changes hemoglobin such that it wont give up oxygen Methgb Conc Methgb % Symptoms <1.5 g/dl <10 % None g/dl 10-20% Cyanotic skin g/dl 20-30% g/dl 30-50% g/dl 50-70% Anxiety, HA, lightheaded Fatigue, confusion, dizziness, tachypnea Coma, seizures,dysrhythmia, acidosis Treatment of methemaglobinemia Methylene blue Dosed IV 1-2 mg/kg of a 1% solution over 5 minutes (max dose = 7 mg/kg) Symptoms generally improve over 1 hour General rule treat when methgb level > 20% 12

13 How does methylene blue work How does methylene blue work G-6-PD G-6-PD How does methylene blue work G-6-PD Patients with G-6-PD deficiency can develop worsening Methemaglobinemia and hemolysis 13

14 A Blue 34 year man old case HIV+ #2 woman - Treatment? presents with c/o feeling lightheaded, nauseated, and short of breath. Vital signs were BP 124/88, P 116, RR 18, O2 sat 82% NRB, Afebrile. She was in no respiratory distress but appeared cyanotic in the lips, gums, face and peripherally in the digits and nail beds. The rest of the exam was unremarkable. ABG = 7.44, PCO2 31, PO2 307, Lactate 1.0 MetHb = 41% Summary Cyanosis may not always be secondary to hypoxemia. Think about alternative causes when supplemental oxygen fails to improve cyanosis. Drugs and medications can cause skin color changes that may mimic cyanosis. Think Methemoglobinemia with decreased O2 sat, cyanosis, and normal PaO2 on ABG. Treatment of methemoglobinemia is methylene blue. Thank you 14