OXYGEN THERAPY: OXYGEN THERAPY: SAFETY & SAFETY & TOXICITYTOXICITY

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ALIRIMBEY ALHAJI ALIRIMBEY ALHAJI ELVIS ELVIS

ANAESTHESIA ANAESTHESIA STUDENTSTUDENT

UDS, TAMALE GHANAUDS, TAMALE GHANA

OUT LINEOUT LINE INTRODUCTION INTRODUCTION INDICATION INDICATION WHO CAN ADMINISTER OXYGENWHO CAN ADMINISTER OXYGEN OXYGEN ADMINISTRATION DEVICESOXYGEN ADMINISTRATION DEVICES TOXICITY AND COMPLICATIONSTOXICITY AND COMPLICATIONS BASIC MONITORINGBASIC MONITORING

INTRODUCTION INTRODUCTION Inorganic gas discovered by Priestly in Inorganic gas discovered by Priestly in

1777. 1777. It forms about 21% of the atmosphere with It forms about 21% of the atmosphere with

a partial pressure of 160mmHg. a partial pressure of 160mmHg. It is a colourless, odourless, tasteless gas. It is a colourless, odourless, tasteless gas. Life supporting component of airLife supporting component of air Highly reactive non metallic element Highly reactive non metallic element

Oxygen is also like a drug/ is drug.Oxygen is also like a drug/ is drug. It must be used meticulously & It must be used meticulously &

diligently.diligently. If abused it can cause SEVERE If abused it can cause SEVERE

complications.complications. Mostly Stored in cylinders for medical Mostly Stored in cylinders for medical

use use E-cylinders – 660 litresE-cylinders – 660 litresH- cylinders – 7000 litresH- cylinders – 7000 litres

INDICATIONS INDICATIONS A.A. Hypoxia ( O2 in tissue ) Hypoxia ( O2 in tissue ) B.B. hypoxaemia ( O2 tension arterial blood) hypoxaemia ( O2 tension arterial blood) 1.1. COPDCOPD2.2. Severe pneumonia Severe pneumonia 3.3. sickle cell crises sickle cell crises 4.4. Severe anaemia, heart related dxsSevere anaemia, heart related dxs5.5. Maternal/Fetal distress Maternal/Fetal distress 6.6. Brain injury /unconsciousness Brain injury /unconsciousness 7.7. Patients under anaesthesia and in PACU Patients under anaesthesia and in PACU

C.C. Hypercapnia and Hypercarbia Hypercapnia and Hypercarbia (PaCO2) > 45(PaCO2) > 45

Vasodilation in systemic circulation Vasodilation in systemic circulation Vasoconstriction in pulmonary Vasoconstriction in pulmonary

circulationcirculation Direct cardiac depressantDirect cardiac depressant Increase cerebral blood flowIncrease cerebral blood flow

Respiratory failure Respiratory failure

Who can Who can administer ????administer ????

Security men (can initiate) Security men (can initiate) Drivers (can initiate) Drivers (can initiate) Orderlies (can initiate)Orderlies (can initiate) All health workers All health workers After initiation it should be regularized After initiation it should be regularized

by by qualifiedqualified health personnel health personnel Doctor, PA, Snr. Doctor, PA, Snr.

Nurse/Midwife/Critical care staff Nurse/Midwife/Critical care staff

O2 DELIVERY O2 DELIVERY SYSTEMSSYSTEMS

1. Low flow or variable performance 1. Low flow or variable performance systems.systems.

2. High flow fixed performance 2. High flow fixed performance systems.systems.

LOW FLOW LOW FLOW SYSTEMSSYSTEMS

1. Nasal catheters1. Nasal catheters 8-14 G, passed through into 8-14 G, passed through into

oropharynx.oropharynx. Reservoir of O2 builds up in pharynx.Reservoir of O2 builds up in pharynx. Optimal saturation Optimal saturation At 1 – 8 L/minAt 1 – 8 L/min Well toleratedWell tolerated For mild cases For mild cases Fio2 24 -44Fio2 24 -44

3.Simple O2 masks:3.Simple O2 masks:- Covers the nose & mouth.Covers the nose & mouth.- 6-10 littres/min.6-10 littres/min.- FiO2 40 - 60%FiO2 40 - 60%- Feeling of suffocation.Feeling of suffocation.- Interference with daily activities.Interference with daily activities.- Displacement at nights.Displacement at nights.

4. Mask with 4. Mask with reservoir bags:reservoir bags:

-Polymask with 2 chambers.-Polymask with 2 chambers.-High FiO2 95% -High FiO2 95% with 10 - 12 lit/min with 10 - 12 lit/min --

HIGH FLOW HIGH FLOW SYSTEMSSYSTEMS

VENTURI MASKS:VENTURI MASKS:

- Total flow is high with or without - Total flow is high with or without entrainment.entrainment.

- Works on Bernoulli principle.Works on Bernoulli principle.- Can deliver O2 at accurate concs.Can deliver O2 at accurate concs.

O2 HOOD:O2 HOOD:- Used in bed bound infants not Used in bed bound infants not

intubated.intubated.- Made of plexi glass.Made of plexi glass.- Humidified O2 Humidified O2

O2 TENTO2 TENT- Used in pediatric practise.Used in pediatric practise.- 10-12 lits/min.10-12 lits/min.- Fire accidents.Fire accidents.

O2 CONCENTRATORO2 CONCENTRATOR

JET VENTILATIONJET VENTILATION

- High frequency oscillation.High frequency oscillation.

HAZARDS OF O2 HAZARDS OF O2 THERAPYTHERAPY

1. Drying of mucous membrane.1. Drying of mucous membrane.2. Depression of ventilatory drive 2. Depression of ventilatory drive 3. Reversal of compensatory hypoxic 3. Reversal of compensatory hypoxic

vasoconstriction.vasoconstriction.4. Atelectasis due to absorption 4. Atelectasis due to absorption

collapse.collapse.5. O2 toxicity.5. O2 toxicity.

OXYGEN TOXICITYOXYGEN TOXICITY 1.Pulmonary oxygen toxicity 1.Pulmonary oxygen toxicity

(Lorrain-Smith effect):(Lorrain-Smith effect):- 100%O2 given for 12 hours or more.100%O2 given for 12 hours or more.- 80% O2 for more than 24hrs.80% O2 for more than 24hrs.- 60%O2 more than 36hrs.60%O2 more than 36hrs.

- SymptomsSymptoms: substernal pain,irresistable : substernal pain,irresistable cough, dyspnoea,V.C dec.,compliance cough, dyspnoea,V.C dec.,compliance dec.,pulmonary interstitial edema leading to dec.,pulmonary interstitial edema leading to fibrosis.fibrosis.

2.Retrolental fibroplasia 2.Retrolental fibroplasia - Occurs when PaO2 more than 80mmhg Occurs when PaO2 more than 80mmhg

for more than 3 hrs in new born.for more than 3 hrs in new born.

- Very premature babies are more Very premature babies are more susceptible.susceptible.

- O2 saturation must be around 90-92 %.O2 saturation must be around 90-92 %.

3.C.N.S O2 toxicity 3.C.N.S O2 toxicity (Paul-Bert effect):(Paul-Bert effect):

- Seizures or convulsions Seizures or convulsions - Depressed ventilatory drive Depressed ventilatory drive - Coma Coma - Brain death and eventually death Brain death and eventually death

Basic monitoring Basic monitoring OXYGEN SATURATION OXYGEN SATURATION 95 – 100 Normal 95 – 100 Normal 85 – 94 moderate hypoxia 85 – 94 moderate hypoxia Below 85 – SEVERE Below 85 – SEVERE (active intervention required)(active intervention required) ABGsABGsPH = 7.25 – 7.35PH = 7.25 – 7.35PaO2 > 60 mmHgPaO2 > 60 mmHgPaCO2 = 35 – 45 mmHgPaCO2 = 35 – 45 mmHgHCOHCO33- = 22 – 26 mEq/L- = 22 – 26 mEq/L

Safety Safety Avoid open fires around oxygen cylinders Avoid open fires around oxygen cylinders Must always be on upright position when Must always be on upright position when

in usein use (secure all cylinders)(secure all cylinders) No grease in in cylinder heads No grease in in cylinder heads Tubing should be disposable if not must Tubing should be disposable if not must

be processed as any reuse items be processed as any reuse items Culture atleast twice a year Culture atleast twice a year

HAVE A PLEASANT HAVE A PLEASANT DAYDAY

REFERENCE REFERENCE 1.1. www.acog.orgwww.acog.org2.2. www.mayoclinic.orgwww.mayoclinic.org3. Chauhan SP, Magann EF, Scott JR, Scardo JA, Hendrix NW,

Martin JN., Jr emergency cesarean delivery for non-reassuring foetal heart rate tracing: Compliance with ACOG

4. Anaesthesia secretes 5. Text book of anaesthesia 6.6. Paramedic: Airway ManagementParamedic: Airway Management  2011  2011