The Story of Jeff J Messerole, PM Clinical Instructor Spencer Hospital Objectives Tell the story of O Review why the narrative has changed Evaluate our options for oxygen therapy Discuss current evidence based practice for the treatment of hypoxia / hypercapnia 1
But we ve always done it that way During rig check at the monthly staff meeting Tina remembers to check the O2 levels in the tanks. It has been awhile since they had a call and they were due for a good chest pain or stroke call. In the middle of the night, they were called out for a chest pain. Tina said good thing she checked the O2 tanks. Once she got there she placed the patient on O2 at 15 LPM via NRB, gave ASA, obtained a 12 lead ECG and transmitted to the local ED. Enroute she assisted patient with their own NTG. Upon arrival at the hospital O2 saturations were 100% and the nurse immediately took the patient off O2 by mask and placed them on NC at 2 LPM. Sound familiar? Tina was dumb founded. Had she done something wrong? She got the saturations all the way to 100%. Can t get any better than that. Right? 2
A Little Preface To Our Story Pathophysiology Oxygen is necessary for life Lack of it leads to death Hypoxic patients should get Os? Whose hypoxic, who isn t?? How much should they get and How?? Can they get too much? Bottom Line.. Air goes in and out, blood goes round and round, oxygen is good! 3
Once Upon A Time We taught Every 1 L/min flow = 4% above room air What We Failed To Teach Gas % s are estimated in people who are breathing at normal rates and depths Go from 0 L/min 24 L/min If I am passing gas at 6 l/min From 0 6 l/min patient is getting 100% Once patient exceeds that 6 lpm they begin to pull in room air diluting the overall concentration SO If my patient is breathing deeper - exceeding the normal 24 l/min he ll pull in more room air diluting the concentration even more 4
Bottom Line.. Gas % s on these devices are crude estimates and vary from person to person depending on their work of breathing A mask will give a higher percent than a cannula? Right? Once Upon A Time Lets not forget teaching 1 person BVM Demand Valve Transport Ventilator 5
BVM AHA position statement 1 Person BVM no longer recommended since 2010 Capable of delivering 100% O2 Requires an adequate seal 2 people Adequate Tidal/Minute volumes BVM No Chest Rise? Mrs Ope M - Mask seal R - Reposition the head S - Suction O - OPA /NPA P - Pneumothorax E - Equipment failure 6
Demand Valve - FROPVD 100% Oxygen 0 160 lpm O2 flow 5 lpm = 8 9 psi No sense of lung compliance Will be removed from Scope January 2019 Transport Ventilator Within Scope of Practice Allowed to set 2 3 variables Tidal volume Respiratory rate Inspiratory time Meaning has become diluted Never caught on 7
Once Upon a Time Or COPD? High flow vs Titrate to maintain sats 88 92% Titrated had reduction in mortality Evolution of Oxygen We then taught Non rebreather at 15 LPM for all Trauma patients Heart attacks Strokes If unable to tolerate then NC at 4 6 LPM Essentially everyone got oxygen in some form. 8
Why So Much Oxygen? Saturate the blood with a higher % of oxygen Made sense If a little is good..more is better Right? Who needs Oxygen We all do! Oxygen + Glucose = ATP What do we call it when we don t get enough? 9
Hypoxia Condition where the body or a region of the body is deprived of oxygen at the cellular level Generalized, affecting the whole body, like during a high altitude ascent - altitude sickness and life threatening HAPE / HACE Locally, affecting a region of the body as in the case of STEMI Has 5 causes Hypoxia vs Hypercapnea Patients can be either Patients can be both Is there a difference? Definitely a difference in treatment 10
Hypercapnea Kapnos Greek for smoke To much CO2 in the blood Who retains CO2? COPD Hypoventilation ( < 10 breaths/min ) Drug OD Narcotics Narcos to sleep During scuba diving rebreathing Leads to respiratory acidosis Giving oxygen does not fix this, what does Hypercapnea Treatment Breathe! Restore adequate rates and depths of breathing to blow off excess CO2 11
Hypercapnea Treatment Don t hyperventilate No more than 1 breath every 3 seconds 20 breaths a minute Hyperventilation increases ITP Pressure collapses superior / inferior vena cava Decreases blood to heart Less in = less out and BP drops Literally hyperventilate your patient to death Hypoxia Five causes of tissue hypoxia Hypoxemic Circulatory Anemic Histotoxic Oxygen Affinity 12
Hypoxemic Hypoxia Without a doubt the most common cause of tissue hypoxia Most common vital signs Tachypnea Hyperpnea Tachycardia Cyanosis Low oxygen saturation All Hypoxic Patients Will Be Cyanotic What is cyanosis? What causes it? How can a patient be anemic? Hemorrhage Iron poor blood Heavy menstruation GIT diseases leading to blood loss Cancers 13
Iron Deficiency Anemia Iron Poor Blood Who s at risk? Greatest Thing Since Popcorn Pulse Oximetry What is it telling you? How recent is the information? How reliable is it? 14
Pulse Oximetry 7 Factors effecting reliability Finger Nail polish or pigment on finger tip Dirty probe Poor perfusion shock hypothermia Patient movement Bright overhead light CO / CN poisoning Smoking / Smoke Low batteries Pulse Oximetry Plethysmograph Measures pulsatile flow Good pleth vs bad pleth Quality assurance check Does patient s pulse match the pulse displayed by oximeter? 15
Results of Reliable Pulse Oximetry 94% - 96% = Acceptable 93% or less = Assess the need for Os 88% - 93% = Hypoxic Drive Problem (COPD) 100% = CO poisoning / Hyperoxia 83% or less = Question reliability Treat the patient not the device Oxygen Oxygen therapy has always been a major component of EMS Oxygen is good and should routinely be put on everyone Patients psychologically believe it cures them regardless of their illness 16
A little Oxygen Won t Hurt Anyone A little probably not A lot definitely so Free radical formation Atelectasis Reduces Coronary Artery flow Increases mortality in heart attack and stroke patients Oxygen Oxygen is a double-edged sword It can be beneficial Documented hypoxia It can be harmful Unintentional hyperoxia Free radical production 17
What are Free Radicals? Atoms that have one or more unpaired electrons They need to pair Oxygen has 2 unpaired electrons making it a likely candidate for free radical production Hydrogen peroxide Nitric oxide Super hydroxyl radical Chemistry of Oxygen An excess of freeradicals damages the cells particularly lung, heart, and brain. Called oxidative stress 18
Chemistry of Oxygen Cells receive about 10,000 free-radical hits /day Antioxidants can normally process these Chemistry of Oxygen But add the unstable oxygen molecule.. 19
Chemistry of Oxygen Aging is associated with effects of freeradical bombardment As we get older our antioxidant enzyme systems are less effective We experience first hand oxidative stress Current Role of Oxygen Reasonable for HCP to use 100% oxygen during CPR In other cases where hypoxia is suspected Monitor O2 saturations Titrate oxygen delivery to maintain adequate saturations Avoid hyperoxia 20
Current Role of Oxygen What are adequate saturations? Does it depend if you have COPD or Not? What is their normal? Hypoxia by definition is a saturation < 94% What if my normal is 88%? How Do We Improve Oxygen Saturations? Give em O s!! How much and with what is the million dollar question 21
Current Practice Debate should shift to low flow vs no flow We have the means to titrate oxygen meet the needs of each individual patient Requires an assessment to determine: What s normal? Do they need oxygen? How much? With what? Who Needs Oxygen? Based on Chief Complaint C/O SOB, difficulty breathing, hard to breath, can t catch my breath Signs and Symptoms of in WOB Tachypnea Tachycardia Accessory muscle use Dyspnea during speech Tripod position Nasal flaring Head bobbing Seesaw breathing Grunting 22
Current Practice Spontaneously breathing patient - If initial reliable saturations are 90 94% a trial of low flow oxygen by NC (2 6 lpm) is warranted Titrate to a saturation of < 98% WOB Current Practice Spontaneously breathing patient - WOB If unable to maintain saturations < 94% consider switching to a mask (10 15 lpm depending on the type of mask) 23
Current Practice Spontaneously breathing patient - WOB If not tolerating a mask consider the use of highflow nasal cannula - HFNC Larger bore allows for greater gas flow < 10 kg start at 2 lpm/kg > 10 kg start at 2 lpm/kg up to 60 lpm EMS flow rates on our flowmeters? High Flow Nasal Cannula (HFNC) Indicated in acute respiratory failure Used successfully in COPD, endstage cancer and do-not-intubate patients Eliminates most anatomic dead space Creates a reservoir in the oral cavity Improves gas exchange ( 1 mm PEEP / 10 L/min of flow ) Significantly reduces WOB 24
HFNC vs NRB Current Practice Spontaneously breathing patient - WOB Consider CPAP if conscious and BP > 90 mmhg Start at 5 cmh2o and reassess every 5 minutes Increase up to 10 cmh2o if needed You ll have to sell it 25
Current Practice Spontaneously breathing patient - WOB If patient is still showing signs of respiratory distress / failure Position Comfortable Do Not Lie Flat Unresponsive Open airway Adult vs Child Current Practice Spontaneously breathing patient - WOB If patient is still showing signs of respiratory distress / failure Assess the need for suction Rigid Soft Measure On the way out No more then 300 mmhg Until clear 26
Current Practice Spontaneously breathing patient - WOB If patient is still showing signs of respiratory distress / failure Assist with BVM Easy peasy Right? Adequate tidal volumes / minute volumes Current Practice Spontaneously breathing patient - If unable to maintain saturations ALS RSI Placed on a ventilator WOB 27
Current Practice Unresponsive Apneac With a Pulse Rescue Breaths BVM 1 every 5 6 secs in adults 1 every 3 5 secs in infants /children Access for gag reflex OPA / NPA Supraglottic Airway Device Current Practice Pulseless, Apneac or Agonal Respirations High Quality Chest Compressions 30 2 ( 10 breaths a minute ) 15 2 ( 20 breaths a minute ) Once advanced airway is placed 1 every 6 seconds regardless of age ( 10 breaths a minute ) 28
Special Notes By no means am I suggesting that patients who need oxygen should be denied Hypoxia must be corrected immediately regardless of its cause Not all your patients are hypoxic or are suffering from hypoxemia We need to be able to identify who is and what will fix it. Take Homes. Treat your patient not the machine Low flow vs no flow Gas % s on O2 devices are crude estimates Titrate to maintain saturations < 96% for acutely ill patients Don t lie patients flat Don t hyperventilate Remember.. Air goes in and out, blood goes round and round, and a little oxygen may be good 29
Summary Told the story of O Reviewed why the narrative has changed Evaluated the options for oxygen therapy Discussed current evidence based practice for the treatment of hypoxia / hypercapnia Thank you for all you do! You guys and gals rock! Jeff Messerole jmesserole@spencerhospital.org 30