Orotracheal Intubation – Medical Procedures – Medstudents

The height of the table where the patient is lied, should be adjusted so that the patient’s face is at the level of the xiphoid cartilage of the standing person who is performing the procedure. Elevating the patient’s head about 10 cm with pads under the occiput and extension of the head at the atlanto-occipital joint (sniffing position) serve to align the oral, pharyngeal, and laryngeal axis, so that the passage from the lips to the glottic opening is almost a straight line. This position permits better visualization of the glottis and vocal cords and allows easier passage of the endotracheal tube. For children under 1 month of age, the head should be in a neutral position. See Figure 1.

Figure 1:Letter A shows the wrong and letter B shows the correct position of patient’s head.

Dr Hernandez

3/1/09

Pulmonary Embolism

• Pulmonary artery blockage
• Risk factors 5 Fs – female, fat, forty, fertile, fair
• Usually present in the acute with normal lung sounds
• After that area of lung becomes ischemic it may start wheezing and then after a while – alveolar collapse and absent lung sounds
• Saddle embolism – immediately fatal
• Pain with walking , diameter of one leg bigger than other
• Usually will not travel far enough to cause CVA as gets trapped in lungs

Contributing factors

• Venous injury, venostasis, increased coagulability (triad)
• Pregnancy (blood loss, tearing of placenta, hypercoagulability)
• Disease (cancer, tumors,
• Multiple trauma, hemostasis
• Immobility after surgery, other prolonged immobility

PE Assessment

• Cough
• Hemoptysis (rare)
• Pain
• Anxiety
• Syncope
• Hypotension
• Pleural rub
• Tachycardia
• Tachypnea
• Fever (rare)
• JVD
• Localized crackles, wheezing

PE Management

• O2
• EKG Monitoring
• Pulse Oximeter
• IV NS or LR
• Rapid Transport

URI

• Nose throat sinuses larynx
  
• Cold pharyngitis tonsillitis sinusitis laryngitis croup
  
• Rarely life threatening
  
• hand washing – key
  
• beware if immunocompromised, transplant patent, infants
  

Some other pediatric lower respiratory infections

• Bronchiolitis
  also see
  AAP Policy
  
• RSV – Respiratory Syncytial Virus
  

Spontaneous Pneumothorax

• dyspnea , chest pain, pallor, diaphoresis, tachypnea

Tension Pneumothorax

• Absent one side , greatly diminished on other
• JVD, muffled heart tones, tracheal deviation

Pharmacological Management

• Oxygen
• Albuterol – asthma, copd, anaphylaxis
• Epinephrine
• ipratropium – Anticholinergic – caution with peanut allergies
• Isoetharine
• Alupent -
  metaproterenol
  
• Racemic epinephrine – upper airway – nebulized – croup
  
• Terbutaline
• Magnesium sulfate
• Corticosteroids

ARDS – common causes

• Always a precipitating event
• Sepsis
• Bronchial aspiration of gastric contents
• Multiple trauma
• Inhalation – fires
• 12-48 hours for S&S
• Young people with no medical Hx
• Can occur in peds

Cystic Fibrosis

• Thick secretions
• Can lead to many other respiratory problems

More discussion about EKG machines and ECG monitoring will be discussed in future lectures.

Dr Hernandez

2/25/09

Pathophysiology of Ventilation Problems

Upper Airway

• Trauma
• Epiglottis
• Croup
• FBAO
• Tonsillitis

Lower Airway

• Trauma
  • Blunt
  • Penetrating
• Obstructive Lung Disease – (COPD; emphysema and chronic bronchitis, asthma – smooth muscle spasm)
• Restrictive lung disease – loss of lung compliance causing incomplete lung expansion and increased lung stiffness.
• Tension Pneumothorax
• Pneumo/hemo thorax
• Acute Respiratory Distress Syndrome (ARDS)(bruised lungs, ecchymotic, swelling etc)
• Airway edema, anaphylaxis, smoke inhalation, APE
• Empyema – puss purulent material secondary to pneumonia
• Plural Inflammation – will cause pleuritic chest pain
• CF, MS
• Neurologic problems
• Depressants
• CVA
• Head problems
• Phrenic or spinal nerve dysfunction
• Airway burns – soot around the mouth
• Asbestosis
• Blebs
• PE –(off plane, long period of immobility, DVT, recent surgery)

Interstitial Space Pathophysiology

• Pulmonary Edema
• ARDS
• Near Drowning – freshwater vs. saltwater – Freshwater can be more dangerous than saltwater in secondary drowning. When fresh water enters the lungs it is pulled into the pulmonary circulation via the alveoli because of the low capillary hydrostatic pressure and high colloid osmotic pressure. Consequently, the plasma is diluted and the hypotonic environment causes red blood cells to burst (hemolysis). The resulting elevation of plasma ^K+ level and depression of N^a+ level, due to the hemolysis, alter the electrical activity of the heart. Ventricular fibrilation often occurs as a result of these electrolyte changes.

  
  Additionally, if drowning occurs in very cold water ( <1^0o C), the uptake of cold water into the vascular system can stop the heart. In open heart surgery, the technique of pouring cold saline solution over the heart is used to prevent heart action. If the victim is resuscitated death can occur hours later due to renal failure. During hemolysis, hemoglobin is also released into the plasma which can accumulate in the kidneys leading to acute renal failure. In contrast, salt-water drowning does not lead to uptake of inspired water into the vascular system because it is isotonic to blood. Therefore, no red cell hemolysis occurs and the cause of death is asphyxia.

• Max Lung Capacity – 6L
• Dead space – 150ml
• Tidal volume 5-6 ml/kg – 6-8ml/kg for peds
• Minute volume
• Alveolar Volume
• Inspiratory reserve volume, max amount that can be inhaled
• Forced Expiratory Volume (FEV)
• Residual Volume – amt remaining in lung after exhalation

Acid Base Balance

• Normal ph 7.35-7.45 – out of this range normal metabolic process cannot occur properly, acidosis more harmful and more acute than alkalosis
• (3 mechanisms of H+ removal – kidneys hold on to bicarb)
• Decreased ventilation = Retention of co2 = acidosis
• Hyperventilate = blow off co2 = alkalosis = nerve ending malfunction, tingling, carpopedal spasm
• The Bicarbonate buffering system is the most important buffer solution for maintaining a relatively constant pH in the plasma. It functions via blood buffering with bicarbonate. The enzyme carbonic anhydrase maintains the equilibrium between bicarbonate and H₂CO₃. This is, in turn, converted into carbon dioxide and water.

Most common cause of hemoptysis, chronic bronchitis, blebs, lung CA, TB – The origin of blood can be known by observing its color. Bright red, foamy blood comes from the respiratory tract while dark red, coffee-colored blood comes from the gastrointestinal tract.

COPD - Blue Bloaters vs Pink Puffers (The effort made by patients suffering from emphysema during exhalation, causes a pink color in their faces, hence the term commonly used to refer to them, “pink puffers”.) (Patients with advanced COPD that have primarily chronic bronchitis rather than emphysema were commonly referred to as “blue bloaters” because of the bluish color of the skin and lips (cyanosis) seen in them.)

• Emphysema – destruction of alveolar walls –
• Chronic bronchitis – too much mucus production

The Pores of Kohn are pores between adjacent alveoli, or interalveolar connections. They function as a means of collateral ventilation; that is, if the lung is partially deflated, ventilation can occur to some extent through these pores. The pores also allow the passage of other materials such as fluid and bacteria.

Pursed lips breathing – patient is building pressure to alveoli to help breathe. Self PEEPing

Asthma

• Reactive airway disease
• More common in peds and young-middle adults
• Triggers – Extrinsic in Peds, Intrinsic in adults
• Reversible airflow obstruction due to:
  • Bronchial smooth muscle constriction
  • Overproduction of mucus
• Breath Stacking – can’t exhale complete volume – leads to hyperinflation of alveoli
• Breath trapping – physical finding, chest gets bigger
• Bronchiole is obstructed on expiration – mucus plugs
• Hypertrophy of smooth muscle in asthmatics vs COPD

Assessment

• Inspiratory wheezing – larger airways
• Expiratory wheezing –
• Silent chest may mean severe obstruction – flow too low to generate sounds – BAD!
• As lungs are hyperinflated – cause symptoms of cardiac tamponade – narrow pulse pressure – pulsus paradoxus
  >20
• As they get better they may start wheezing and bringing up mucus – as bronchodilation is occurring

Status Asthmaticus – severe and prolonged – taking his meds all day, etc. True Emergency – Up Triage – imminent threat of respiratory failure

Role of Magnesium Sulfate in Asthma, Maged A. Zaki, MD in
Medscape

Magnesium sulfate has been shown to inhibit smooth muscle contraction, decrease histamine release from mast cells, and inhibit acetylcholine release. Studies both in children and adults have shown variable improvement in patients with severe airflow limitation who are unresponsive to standard treatment with beta agonist, anticholinergic, and corticosteroid medications. Ciarallo has shown in 2 studies of children that the optimum dose is 40 mg/kg given as an intravenous bolus with a maximum dose of 2 g. In 1 study, improvement in forced expiratory volume in 1 second (FEV₁) was seen within 20 minutes and continued for up to 110 minutes. Up to a 20% improvement in FEV₁ may be seen. In adults, a study by Silverman has shown that patients with an initial FEV₁ lower than 25% of what was predicted benefited the most from magnesium sulfate therapy.

Asthma is classified according to the frequency of symptoms, FEV₁ and peak expiratory flow rate.^[4]

Respiratory sounds: Stridor ·
Wheeze ·
Rales ·
Rhonchi ·
Hamman’s sign

Dyspnea ·
Hyperventilation/Hypoventilation ·
Hyperpnea/Tachypnea/Bradypnea ·
Orthopnoea/Platypnea

Biot’s respiration ·
Cheyne-Stokes respiration ·
Kussmaul breathing

Hiccup ·
Mouth breathing
Asphyxia ·
Cough ·
Pleurisy ·
Sputum

Respiratory arrest ·
Hypercapnia/Hypocapnia

2/18/09 – Dr Hernandez

Respiratory Emergencies 1

Control of breathing

• Involuntary centers start in Pons, Medulla
• Pons regulates pattern
• Apneustic center – controls length of inspiration
• Pneumotaxic center – expiration
• Central chemoreceptors – separated by blood brain barrier
  • Responds to PaCO2
    • Diffuses across blood brain barrier
    • Changes PH of CSF
• Peripheral Chemoreceptors
  • Respond to decreased o2 supply (carotid bodies, aortic arch)
  • Secondary drive – hypoxic drive
  • Low Hb saturation
  • Decreased perfusion
• Baroreceptors
  • Sense pressure changes
  • respond to low BP
  • hypovolemia
• hypoxia vs hypoxemia
  • hypoxia – low tissue oxygen
  • hypoxemia – low blood oxygen (sp02 – pulse oximeter)

Rate controlled by CO2 level in Medulla

• Tachypnea vs bradypnea refers to rate
• Hypopnea vs hyperpnea refers to depth
• Orthopnea – SOB while lying down
• Pluerodynia – painful breathing
• (Platypnea – SOB while sitting up)
• Dyspnea – subjective description

Hyperventilation vs Hypoventilation

• Hypocarbia – hypercarbia

Patient can be tachypneic without hyperventilating

• Cheyne-Stokes – regularly irregular – alternates between apnea and tachypnea – damage to control centers
• Biots – Irregular chaotic – severe brain injury or brain stem herniation – abnormal pattern of breathing characterized by groups of quick, shallow inspirations followed by regular or irregular periods of apnea.^[
• Apneustic Breathing – prolonged inhalation – severe brain injury
• Kussmaul’s – too much acid, body trying to blow off excess – rapid deep – seen in in DKA, metabolic acidosis

Lung Receptors

• Pulmonary stretch receptors
• Herring-Breuer Reflex

Irritant Receptors

• Cough receptors
• Epithelium of tracheal bronchial tree
• Cause sneeze cough, laryngospasm
• Vasovagal response

(Saddle Embolus – deadly)

Normal Spo2 & PaCo2

• Spo2 -90-97% acceptable to maintain life, 80s for chronic smokers or COPD – keep neonates, preemies at 93% to prevent o2 damage
• 35-45mm normal PaCo2
• 97% of o2 in blood carried by Hb
• Each Hb takes 4 o2 molecules (a pulse oximeter will read 100% when Hb saturated with 3 o2 molecules)
• As atmospheric pressure rises you have a higher uptake of 02 – so at high altitudes you will have lower sats
• You can saturate more o2 in a cold liquid, warm environment requires higher pressure to saturate same o2
• 70% of co2 transported as bicarbonate, easier to cross membranes,
• Some Hypercarbia causes – opiates, resp arrest, obstructive diseases, obstructions, etc
• Any increase in metabolic rate will cause rate to increase and vice versa

Initial assessment

2/2/09

Functions of the respiratory system

1. Exchange of gases
2. Excretory function (volatile substances – alcohol, garlic, acetone, etc)
3. Acid Base Balance

Metabolic and aerobic metabolism

Respiratory Physiology

1. Ventilation
   1. Hyper/Hypo refers to depth of ventilation and leads to hypo/hyper carbia
   2. Eupnea – normal breathing
   3. Tachypnea
   4. Braydpnea
   5. Apnea
   6. Dyspnea
2. External Respiration – alveolar capillary membrane (also have bearing on acid/base levels due to transport of co2)
3. Internal Respiration – cellular respiration (also have bearing on acid/base levels due to transport of co2)
4. Transportation of Gases – O2 transported on hemoglobin, (hemoglobin is directly affected by temperature, in cold it picks up O2 but does not release it easily in the tissues – red cheeks because blood is cold O2 stays in the vessels) alkalosis – o2 not given up by Hgb, acidosis- o2 given up by Hgb much faster
5. Regulation –

Physics of ventilation

1. Boyle’s Law – describes how air moves in and out of lungs
   
2. Dalton’s Law of Partial Pressure – distribution of gas
   
3. Henry’s law of Solubility of gases – describes how gases dissolve in water
   

To be continued….

1/7/09 (UPDATED 1/11/08

RSI (Rapid sequence intubation)

Indications:

• Trauma with GCS of <9, with gag reflex or significant facial trauma
• Closed head injury – major stroke
• Burn patients
• Any patient who can’t maintain an airway, still has gag reflex,- with possibility of successful intubation

6 ps

• Prep
  
• Preoxygenate, sat at 100% (do not bag while patient is under, all sphincters are relaxed)
• Pretreat (medicating)
  • LOAD
    • Lidocaine – 1-1.5 mg/kg (suppress gag reflex – gag can increase ICP)
    • (Opiods – Fentanyl 3mcg/kg IV – decrease sympathetic response – also for AA or ICP)
      
    • Atropine –0.02 mg/kg – decreases parasympathetic response (also decreases brady affect of Succinylcholine- especially peds)
    • (Defasiculating dose – 10% of normal dose (non-depolarizing) – 2-5 minutes before Succinylcholine)(
      Vecuronium 0.1mg/kg) -
      

       

• Induction (sedation)
  
  • Etomidate – 0.3 mg/kg
    • Rapid onset – 15-45 sec
    • Short duration – 3-12 min
  • Midazolam (Versed) – 0.1-0.3 mg/kg – usual dose is 2 mg because causes hypotension
    • 30-60 sec onset
    • 15-30 minute duration
    • Amnesic effects
• Paralysis (not performed in NYS by paramedics)
  
  • Bind to ACH nicotinic receptors
  • Depolarizing
    • Succinylcholine (sux) – binds to Ach receptors blocking contraction of muscle
    • 1-2mg/kg – max 150mg
    • Peds 1-1.5mg/kg
      • Hyperkalemia (renal problems, significant muscle damage, burn patients, )
      • Bradycardia
      • Dysrythmias
      • hypertension
  • Non-depolarizing
    • Do not cause fasciculations
    • Longer onset
    • Longer action
  • Paralyzed patient has no definitive airway
  • Must be ventilated manually throughout duration of paralysis
  • No affect on mental status – MUST sedate
• Placement of tube
  
• Post intubation management

12/17/08

Nasotracheal Intubation

• Blind
• Pt must be breathing spontaneously
• Indications
  • Conscious patients
  • Possible spinal injury
  • Trismus (clenched teeth)
• Contraindications
  • Head injury
• Equipment
  • Smaller size tube
  • No scope
• Technique
  • Preoxygenate
  • Advise to inhale
  • Lube with KY
  • Aim tip towards ear
  • Position just above glottis opening
  • Auscultate and otherwise confirm placement

Digital Intubation

• No scope
• Blood
• Bite block
• Left hand open epiglottis using index and middle fingers along right side of mouth, advance tube with right hand along left side of mouth
• Pass tube 2 inches past your fingers
• Use bite block
• Not for peds

   

ET Suction

• Sterile technique
• May cause arrhythmias and vagal response
• Avoid unless causing obstruction
• Pre and post oxygenate
• Pour sterile water down ET tube
• Introduce catheter and engage suction on way out for <15 sec

Extubation

• Hyperogygenate
• Have equipment
• Confirm responsiveness
• Lean forward
• Suction oropharynx
• Deflate cuff
• Extubate as pt coughs or exhales

Pediatrics

• Miller blade (floppy epiglottis)
• Preemie – size 0
• Size of pinky or >1 year age/4+4= size
• Use Braslow tape
• Smaller size are cuffless
• Curve stylet upwards, airway more anterior and superior
• Can cause parasympathetic response – counter with Atropine Sulphate
• Sniffing position
• Record depth of tube
• Confirm proper placement
• Breath sounds travel easily in children

DOPE (troubleshooting a deteriorating patient)

• Displacement – re-auscultate
• Obstruction – suction
• Pneumothorax – absent sounds on one side
• Equipment failure –

CPAP (Continuous Positive Airway Pressure)

• Used in CHF, obvious difficulty, oxygenated (maintain own airway)- increases pressure in the alveoli to keep fluid in vascular space and out of lungs
• Contraindications
  • AMS
  • No patent airway
  • COPD
  • More…
• Connect to o2 tank. Set pressure to 5cm at minimum – increase to 10cm max.
• Introduce slowly to patient

Chest decompression

• Evacuate air in the pleuritic space
• Indications (all required)
  • JVD
  • Obvious dyspnea
  • Tracheal deviation

Procedure

• Landmark: 2^nd intercostal space – (above third rib – below ribs contains vasculature and nerves)
• Listen for air escape
• Create a flutter valve – use a glove finger

12/7/08

Patient Airway – No airway, no patient

Upper Airway – Major function, warmer, filter and humidly air.

Turbinates – three bony shelves in nasal passage – increases surface area

Sinuses – Cavities formed by the cranial bones

• Fractures of these bones may cause cerebrospinal fluid to leak from the nose or the ears.
• Significant bleeding from sinus fractures
• Prevent contaminants from entering the respiratory tract

LeFort Fractures – facial fractures

Hyoid bone, beneath mandible, anchors tongue, only non articulating bone in the body, attached with tendons

Palate – Hard and Soft

Adenoids and tonsils : lymphatic tissue that filter bacteria, severe swelling can cause airway obstruction

Vallecula – between base of tongue and epiglottis –It is an important landmark in intubation;

Larynx – divides upper and lower airways

• Anatomy – In order, Superior to inferior;
  • Laryngeal prominence (Adam’s Apple)
  • Thyroid Cartilage (V shape, shield) –Directly anterior to glottic opening
  • Cricothyroid membrane – site for surgical access to airway – bordered laterally and inferiorly by thyroid gland
  • cricoid cartilage – lowest portion of larynx – first ring of trachea, only upper airway structure that forms a complete ring
• Interior Airway Structures
  • Glottis – space between vocal cords – narrowest point of adult airway
  • Arytenoid cartilage – posterior attachment of vocal cords
  • Pyriform fossae – Two pockets of tissue on the lateral borders of the larynx – may cause tenting if tube placed there inadvertently

     

• Sellick Maneuver or BURP (Backward Upward Rightward Pressure)used to manipulate the larynx into view during intubation
• If you don’t see landmarks, you may be looking down the esophagus, pull back on laryngoscope and epiglottis should come into view

Lower airway

• Externally from 4^th cervical vertebrae to xyphoid process
• Trachia,(enters lung at hilum) Bronchi, smaller bronchi, bronchioles, alveoli (functional site for respiration (i.e. gas exchange)
• Trachia bifurcates at the Carina
• R has 3 lobes, L has 2 lobes
• Visceral pleura and parietal pleura
• Ventilation vs Respiration
• Shunting (blood bypasses the alveoli and does not exchange gasses)
• Alveoli lined with surfactant
• Atelectasis
• Avg adult 6L of air volume
• Tidal volume (Vt), 5-7Ml/kg adult, 6-8mL/kg (500 mL)
• Alveolar volume = tidal volume minus dead space(Vd)
• Minute volume (Vm)– amount of air that passes over a minute (Vt – Vd x Resp Rate)
• Functional reserve capacity – amount you can force out in single exhalation – (about 1200mL)
• Ventilation- Inhalation 1/3^rd Exhalation 2/3

Regulation of ventilation

• Primary reglated by PH levels in CSF
• Phrenic nerve- innervates the diaphragm
• Intercostals nerves – innervates the intercostals muscles
• Hering-Bruer reflex –stretch receptors tells the brain that the chest wall is fully expanded – ending inspiration
• Apneustic center – increase respiratory rate
• Pneumotaxic center – counters by inhibiting inspiration
• Chemoreceptors – monitor CO2, O2 and PH levels
• Respiratory drive – primary drive – driven by CO2
• Hypoxic drive – secondary drive driven by O2 (seen in COPD patients)
• Inhalation, muscles contract, pressure decreases – move air into lungs via negative pressure
• Exhalation, muscles relax – pressure increases, air forced out of lungs (passive)

Respiration

• Diffusion
• SaO2 measures saturation of hemoglobin, can be O2 or Co2 – use a pulse oximeter
• Hypercarbia
• Hypocarbia

Abnormal CO2 Concentrations

• As metabolic rate goes up more CO2 is produced
• Hypoventilation – co2 production exceeds body’s ability to eliminate it (hypercarbia)
• Hyperventilation – co2 elimination exceeds production (hypocarbia)
• Minute volume – decreased minute volume causes a decrease in co2 elimination

ET Tube

• Sizes 5.5 up have pilot cuff –
• 5.5 and down are cuffless – for peds
• Age + 16 / 4 = tube size (pediatrics)
• Keep spo2 above 90, hyperventilate before attempts

ETT Verification

• Seeing pass through cords
• Moisture in tube
• Etco2
• Auscultate lungs and abdomen
• Esophageal detector

Tape and secure. Put an oral airway in to hold tongue and prevent biting, record placement level