Monday, February 15, 2016

Week 2

Reflection:
Using the Gibb's Reflective Model, i will be reflecting on the practical session we had on the 8th of February, 2016.

Description: On the 8th of February, 2016 we had our first practical of the course. The session started off with listening to different breath sounds on the mannequin, using a stethoscope. I heard normal breath sounds, crackles, inspiratory and expiratory wheezing, gurgling, mild crackles and stridor. My colleagues and I each took a turn to listen to each sound, and tried to guess what the sound was. In order to do that, I started by placing the diaphragm of my stethoscope on the bare skin of the mannequin. My first placement was at the apex of the right lung, since it was closer to me, and I compared it to the left. I progressed down to the bases of the lungs, comparing both sides at each point. I got all of the sounds correct except the stridor.  After this we proceeded to practicing IM drug administration. Firstly, I put on my PPE and prepared all the equipment I need including: The right medication, a 3mL syringe, a 22G needle, 2 alcohol swabs, the sharps box and some cotton balls. Secondly, I checked for the 5 Rs, the expiry date of the medication and asked the patient for any allergies to the medication. I also obtained consent from the patient to proceed to giving him an IM injection. Thirdly, I wiped the cover of the medication with an alcohol swab and drew up 0.5mL into the syringe, and changed the needle to a sterile one. Fourthly, I placed three fingers below the clavicle and located the deltoid muscle. Fifthly, I told the patient that the injection will hurt and not to move. I then wiped the site of injection with an alcohol swab and held the skin taut. After that I held the needle between my thumb and index finger and inserted it at a 90 degree angle. I then aspirated to make sure I was in the muscle. After confirming I was in the muscle, I injected the medication. Following that I pulled out the needle while pressing on the skin around it, to minimize pain, and placed the needle in the sharps box. Finally, I placed a cotton ball on the site of injection and placed a bandage over it.
Following this we reviewed the use of a BVM, performing IPPV, and laryngoscopy. We discussed about how much to press on the bag of the BVM, the use of OPA, and the rate of ventilations with and without an advanced airway. After that we practiced using a nebulizer mask. I attached the pieces and saw where to place the drug. Also, our instructor told us the importance of putting the nebulizing drug into the chamber and setting up the pieces of the mask and tubing before switching on the oxygen. Moreover, she told us that the recommended oxygen flow was 8L/min. Also, she told us about the importance of adding 2mL of normal saline to avoid drying up the patient’s mucosa. At the end of the session we practiced using a peak flow meter, and I attempted to measure my own peak expiratory flow.
Feelings: I felt excited to learn about the breath sounds and starting my journey of distinguishing between the different sounds. Also, I felt really good when I was able to recognize most of the sounds. When we came to practice IM drug administration, my thoughts were a little scattered and I felt a bit nervous, since there were a lot of details. However, after having my hands on practice I understood the skill better. This helped me feel more at ease and made me want to practice this skill more and more. Afterwards, it felt good to refresh my knowledge of IPPV and laryngoscopy. This made me feel even more confident to perform these skill. Moreover, after practicing using the nebulizer mask, I felt certain of how to set it up and use it. Finally, using the peak flow meter was intriguing and made me more aware of how a patient would feel when asked to blow into the meter. It felt uncomfortable and difficult.
Evaluation: Auscultating the mannequin’s chest for different breath sounds was really good. It helped me distinguish between the different breath sounds. Moreover, learning and practicing how and where to give an IM injection was enlightening and beneficial. While practicing it, I was a little unsure at first but that slowly subsided as I practiced more, and that was a positive aspect.  Furthermore, revising IPPV and laryngoscopy was useful and helped refresh my memory on these skills, which was great. Also, practicing setting up a nebulizing mask and administering nebulizer drugs was advantageous. Moreover, using the peak flow meter was interesting and useful. Therefore, in total this practical session was very interesting and a very good experience.
Analysis: As a start, I believe this session was great. However, I still feel that I need a lot more practice auscultating the mannequin’s chest, until I am able to easily recognize all the different breath sounds. Also, I need more practice doing the IM injection. Although I did a good job in this session, I still don’t feel completely confident and comfortable performing this skill. My teacher said this was normal at first, and that I will feel more capable with time and practice. Revising IPPV and laryngoscopy was great because with time I am bound to forget some details about the skills, and revising it helped me stay on top of it. Practicing setting up a nebulizing mask and administering medication through it was very easy. Furthermore, using the peak flow meter gave me an idea of how my patient would feel if asked to blow into the peak flow meter. It is uncomfortable and knowing this will help me be more understanding to my patient in the future.
Conclusion: The only thing I could have done is practiced more. This is because the skills we learned in this lab session get easier with experience and practice. Therefore, the only thing I need to do to improve further is to constantly train on these skills.
Action Plan: My plan is to use any free time I have to go to the lab and practice auscultating the mannequin’s chest. Also, I want to practice giving IM injections until I feel completely confident in my ability to do it.

Image 1: Me auscultating the mannequin's chest for different breath sounds

Image 2: Equipment used to perform IMI


Image 3: Me inserting the IM needle at a 90 degree angle into mannequin's deltoid muscle

Image 4: Me aspirating to check for correct placement of needle into muscle

Image 5: Me injecting 0.5mL of medication into mannequin's deltoid muscle

Image 6: I disposed the IM needle into the sharps box after giving the IMI. 

Image 7: My set up of a nebulizing mask attached to a patient's face



Learned Concepts:

In the lab I learned that the maximum fluid that can be administered via IM in the deltoid muscle is 0.5 mL.

In this week's lecture we learned about epidemiology revolving around respiratory diseases. Although there is limited data from the UAE about chronic respiratory diseases, we discussed some interesting statistics.
In the world today, there are 235 million people suffering from asthma. Also, there are more than 3 million people that die of COPD in 2005, 90% of which were from the low- and middle- income countries.
In 2011, 3% of deaths in the UAE were due to chronic respiratory diseases. Chronic respiratory diseases are a diverse group of conditions affecting the lungs or respiratory tract for a long time. The three major ones are COPD, asthma, and the Middle East Respiratory Syndrome (MERS). Moreover, respiratory disorders were the second most common non-fatal condition in the UAE in 2010.
It is interesting to learn that 3.7% of Abu Dhabi population had COPD in 2010.
COPD is an inflammatory disease of the small airways and involves chronic bronchitis and emphysema. It is the fourth leading cause of death worldwide and is expected to become the third leading cause in 2030.
It is also interesting to know that 15% of the UAE population is asthmatic and a further 40% have allergic rhinitis. Over the next 25 years, The World Asthma Foundation predicts that respiratory allergies will increase at the rate of 70% in the MENA region.
The difference between COPD and asthma:
COPD is predominantly a neutrophilic inflammation involving CD8 lymphocytes. On the other hand, asthma is mostly a eosinophilic inflammation involving Type 2 helper T lymphocytes.
The presentation of COPD and asthma is very similar, especially in elderly.
MERS is a VIRAL respiratory illness caused by a new strain of coronavirus. It is transmitted, for the most part, from one person to another. However, humans can be infected through direct or indirect contact with infected dromedary camels in the ME.
In 2012-2015 there have been a total of 1,185 cases confirmed, including 443 deaths.
Typically, MERS presents as fever, coughing and shortness of breath. Commonly pneumonia is present. There are also some GI symptoms such as diarrhea. If severely infected, a patient of MERS can suffer from respiratory failure that will require mechanical ventilation and support in an ICU. There is no vaccine or treatment available for this condition. MERS poses a risk to HCP since there are reported cases where the virus was transmitted from patients to HCPs. This was mainly due to lack of application of strict hygiene measures by the HCPs.
To avoid this,HCPs must apply the standard precautions as well as the droplet precautions, contact precautions and eye protection.
23% of the UAE population are daily smokers. This accounts for approximately 1.8 million people. 14% of youth in the UAE also smoke. Smoking among males in the UAE is higher than some of the other GCC countries. However, among females it is lower.
Shisha, which is commonly used in the UAE, has negative effects due to the tar and nicotine intake involved. It increases the risk of lung cancer, respiratory illness, and low birth weight.
Chronic respiratory disease is usually associated with co-morbidities and is often missed.

Additional Readings
This week's lecture was self-explanatory and had very useful and recent statistics. This lecture has taught me so much about the reality of certain respiratory diseases in the UAE, and i did not feel the need to search further.

Stand Out Moment
One thing i hadn't understood that became clear to me this week was about the nature of COPD. I never completely understood what it was and how it differed from asthma. This week in the lecture we learned the difference and this helped me understand clearly what COPD is and how it is very different from asthma. Paying attention during the lecture and revising my notes later helped me understand this difference.

Biggest Impression
This week there are multiple things that made an impression on me as a future paramedic. Firstly, in the lab learning how to perform IMI was really interesting since i will definitely be using this skill as a paramedic. Furthermore, listening to different breath sounds made me more aware of the different respiratory sounds that i will encounter in my practice and how each sound can help guide me in my diagnosis of the patient.
Also, the lecture helped me understand the magnitude of asthma, COPD and MERS in the UAE. This helps me be aware of the population i will be working with in the future. It made me conscious of what i could face in terms of respiratory illnesses in the UAE. Also, it showed me the importance of PPE and precautions with respiratory patients, especially MERS patients. This is because there have been HCPs that have caught this virus during their work. This keeps me alert and careful to ensure my safety around such patients in the future.

Strengths and Limitations
The only limitation i could think of is my performance of IMI. This is expected since i just learnt it this week, however, to help strengthen myself in this skill i need to constantly practice it. Also, my recognition of breath sounds was good but i still have some weakness, since i was not able to recognize all the breath sounds. Therefore, i need to continue practicing this skill and keep trying to recognize the different breath sounds and what they mean.
On the other hand, i felt my ability to perform the other skills revised in the lab session was strong. Revising them helped me strengthen my memory and abilities even further.

Saturday, February 13, 2016

Week 1

On the first of February, 2016 we had our first lecture for BEH2432. Since we did not have any practical session in the first week, there will be no reflection in this entry.

Learned Concepts

The airway includes the following structure in this order: Nose, nasopharynx, oropharynx, epiglottis, laryngopharynx, vocal cords, larynx, trachea, carina, bronchi, bronchioles (Terminal then respiratory), alveolar duct, alveoli.

The glottis is a landmark distinguishing between upper and lower airways. Above the glottis is the upper airway and below the glottis the lower airway.
In the airway, the first cartilage is called the thyroid cartilage and the one inferior to it is the cricoid cartilage. Between them is the crico-thyroid membrane. My teacher told us this membrane is where cricothyroidtomy is performed.

Breathing is the movement of air in and out of the lungs. It is possible due to this chain of events:
Respiratory muscles contract/relax -> causes pressure difference -> Air moves from area of high pressure to low pressure (In/ out of lungs)

When the pressure inside the lungs is <760mmHg, Air moves from atmosphere to inside lungs (Where pressure is lower).
This inhalational process is active where the medulla oblongata commands the inhalational muscles to expand the chest and lungs. This increases the volume of the lungs, and according to Boyle's Law, decreases the pressure. This causes air to move into the lungs.
On the other hand, exhalation is passive. This is because it is triggered by the relaxation of the inspiratory muscles. This leads to the chest and lungs recoiling, decreasing the volume of the lungs, which, according to Boyle's Law, increases the pressure inside the lungs to >760mmHg. Air then moves out of the lungs into the atmosphere, where the pressure will be lower.
Between inhalation and exhalation there are moments where the atmospheric pressure equals the pressure in the lungs. Therefore, no air moves in or out of the lungs. This is why the RR is normally 12 breaths per minute, since our bodies are not continuously breathing.


Figure 1: Diagram showing and explaining the two types of respiration


For oxygen, the pressure is higher in alveoli compared to the pressure in capillaries. This is why oxygen moves from the alveoli to the blood in the capillaries.
For carbon dioxide, the pressure is higher in capillaries when compared with alveoli. This is why CO2 moves from capillaries to alveoli during external respiration.
It is important to note that the PaCO2 is equal to 35-40 mmHg.
External respiration and diffusion is effected by:
1- O2 concentration: increased O2 -> increased diffusion of O2 from alveoli to capillaries
2- Altitude: Harder to breathe at high altitudes
3- Loss of lung tissue: Less tissue -> smaller surface area -> decreased diffusion
4- PEEP, CPAP, BIPAP: high pressure-> increase surface area -> increased diffusion

O2 is transported via blood, in internal respiration, by plasma but mostly by binding to hemoglobin.
However, O2 can only enter tissue cells if it is dissolved in plasma. Therefore, dissolved O2 diffuses into the cells, and then hemoglobin bound O2 will dissolve into the plasma, to enter the cell. For this to happen properly, plasma O2 must always be greater than cellular O2, due to the need of a concentration gradient for diffusion to occur.

Conducting airways conduct air to the lungs. No gas exchange occurs in these airways. They begin at the nose and ends at the terminal bronchioles. These airways warm, humidify and clean the air, prevent foreign matter from entering the respiratory airways and serve as a passageway for air to enter the gas exchange regions of the lungs.
These gas exchange regions include the respiratory bronchioles, alveolar ducts, and alveolar sacs.

The main function of the nose relating to the respiratory system is to clean and humidify air on inspiration by action of cilia and conchae.
The pharynx is the common opening to the digestive and respiratory systems. Divided into: nasopharynx, oropharynx, laryngopharynx.
Larynx (voice box) consists of 9 cartilages: 6 paired and 3 unpaired. The most superior cartilage is the thyroid cartilage. The most inferior cartilage is the cricoid cartilage. The third unpaired cartilage is the epiglottis, which prevents any materials from entering the larynx during swallowing, and directs those materials into the esophagus. The larynx contains true and false vocal cords, which vibrate and produce sounds as air moves past them.
The trachea (windpipe) begins at the cricoid cartilage and ends at the carina. Contains smooth muscle and is supported anteriorly by 16-20 C shaped cartilaginous rings.
Thoracic cavity houses and protects most of the lower respiratory system and is flexible enough to accommodate inhalation, where the chest must expand. The thoracic cavity consists of 12 thoracic vertebrae, each with a respective pair of ribs. These provide protection.
Mediastinum is the area between the two lungs and contains the heart, great vessels, esophagus and the lungs' hilum.

The Bronchial tree starts with the left and right bronchi. The left bronchus is narrower than the right one and angles at a 45-55 degree angle. This inclination protects the left bronchus from aspiration. However, due to the angulation and the force of gravity, the right bronchus is the most common site of aspiration and where the ET tube accidentally enters during intubation.
Main stem bronchi are the first generation of bronchi. The final subdivision of the conducting airways are the bronchioles. Bronchioles consist of only smooth muscle!


Figure 2: Drawing of lungs showing structural similarities and differences between right and left lung
Alveoli consist of epithelial cells of types I and II. Gas exchange between the air spaces contained in the alveoli and the capillaries takes place by diffusion across the alveolar capillary walls.
Type I alveolar epithelial cells are squamous cells that compose 90% of alveolar surface, and provide structure for the alveoli. They are the main site of gas exchange and become inflamed when exposed to toxins, making gas exchange harder. This is because the distance the gas has to travel in and out of the alveolar space and capillaries will become larger. 
Within Type I cells there are Pores of Kohn. Also, there are Cannals of Lambert between Type I cells and terminal bronchioles.
Type II Alveolar epithelial cells are cuboidal epithelial cells with microvilli. These cells secrete alveolar fluid which keeps the surface between the cells and air moist. They also produce, store and secrete pulmonary surfactanct, which consists of phospholipids and lipoproteins. Surfactant reduces the surface tension of the alveolar fluid, which reduces the alveoli's tendency to collapse. This fluid also increases lung compliance and eases work of breathing.
Alveolar macrophages are wandering phagocytes that remove fine dust particles and other debris from the alveoli. They move through the Pores of Kohn.
Respiratory membrane (through which gases diffuse): Alveolar wall -> Epithelial basement membrane -> Capillary basement membrane -> Endothelial cells of capillary (Entire membrane= 1/6 diameter of RBC.)
Capillaries allow RBCs to pass through them in a single file. Each RBC is exposed to alveolar gas of two or three alveoli.
Two vascular systems supply the respiratory system:
1- Pulmonary circulation: Pulmonary artery (carrying deoxygenated blood) from rt side of heart -> lungs (gas exchange at alveoli across respiratory membrane) -> Pulmonary vein (carrying oxygenated blood) to lt side of heart -> Systemic circulation
2- Bronchial circulation: Vascular system branching from aorta, that provides perfusion to the tracheobronchial tree. Blood drains into the bronchial veins into the superior vena cava, to return to the heart.

Pleural membranes surround the lungs. Consist of parietal and visceral pleura. 
Parietal -> Attached to thoracic wall
Visceral -> attached to lungs
Pleural fluid is constantly secreted and absorbed. Usually 3-5 mls at any one time. This fluid allows the visceral and parietal pleura to glide against each other during inhalation and exhalation. This fluid is contained in the pleural space.
Within the pleural space there is intra-pleural pressure. Normally intra-pleural pressure is less than atmospheric and intra-pulmonary pressures. Usually intra-pleural pressure is -4cmH2O during exhalation and -10cmH2O during inhalation. 
Intra-pleural pressure results from forces within the chest wall pulling the parietal pleura outwards and elastic fibers within the lungs pulling the visceral pleura inwards. This pressure keeps the lungs inflated. If atmospheric pressure enters the pleural space, such as in pneumothorax, the lung collapses.
The diaphragm performs 80% of work of breathing. The diaphragm separates the thoracic and abdominal cavities and is connected to the sternum, ribs and vertebrae. When it contracts it moves downward, increasing the size of the thoracic cavity -> decreased pressure -> air moves in. In exhalation the diaphragm relaxes, moving upward-> reducing thoracic volume -> increase in pressure -> air moves out.
The diaphragm is controlled by the medulla oblangata via the phrenic nerve (C4). 
Some muscles aid in inhalation and exhalation and these include external intercostals, internal intercostals, scalene, trapezius and sternocleidomastoid. These are called accessory muscles of ventilation. These  muscles enhance chest expansion but are not normally used at rest. If they are used during rest, this is an indication of pulmonary disease.
O2 dissociation curve shows the relationship between dissolved O2, PO2, (x-axis) and hemoglobin bound O2, SpO2, (y-axis). Factors that influence O2 binding including pH, pCO2, Temperature, and 2,3 DPG. Shift to the right means O2 has lower affinity for Hb. Shift to the left means O2 has higher affinity to Hb.
Higher affinity: decreased temperature, decreased 2,3 DPG, decreased [H+], CO poisoning (Hb has higher affinity to Hb -> High SpO2 due to CO binding to Hb, however pt will be hypoxic).
Reduced affinity: increased temperature, increased 2,3 DPG, increased [H+]. 

Ventilation is regulated by:
  • A controller within the CNS (Medulla, Pons, Cerebral Cortex [Voluntary])
  • Group of effectors (muscles of ventilation)
  • Group of central chemoreceptors (Near the medulla oblongata, surrounded by brain ECF)
  • Group of peripheral chemoreceptors (Located above and below aortic arch and at bifurcation of common carotid arteries)
  • Lung receptors (Stretch receptors located in walls of bronchi and bronchioles and respond to hyperinflation, J receptors and irritant receptors)
Central chemoreceptors respond to changes in hydrogen ion concentration in ECF. High [H+] -> increased ventilation. This is to get rid of excess CO2 which will then reduce the [H+].
Peripheral chemoreceptors respond to changes in PaO2, and increase ventilation in response to hypoxia. Carotid receptors respond to increase PaCO2 and increase ventilation accordingly.
Lung receptors send messages via vagus nerve to the pons to begin expiration, in case of hyperinflation of lungs. This is know as the Hering-Breuer reflex. 
Hering-Breuer reflex: Hyperinflation of lungs -> stretch receptors in bronchi and bronchioles triggered-> signal sent via vagus nerve -> Pons -> Exhalation begins
J receptors are located in alveolar walls close to capillaries. If there is engorgement due to increased interstitial fluid at the alveolar wall, the J receptors stimulate ventilation.
Irritant receptors lie between airway epithelial cells and function to stimulate coughing in response to inhaled irritants.

Figure 3: Diagram showing Respiratory volumes
ABG:
pH: 7.35-7.45 (acid/alkaline)
PO2: 80-100 mmHg (hypoxaemia)
PCO2: 35-45 mmHg (respiratory acidosis/ alkalosis)
HCO3: 22-26 mmol/L (metabolic acidosis/ alkalosis)

Respiratory Status Assessment include:
Position, Patient's appearance, speech, breath sounds, chest auscultation, respiratory rate, respiratory rhythm, breathing effort, pulse rate, skin condition, and consciousness state.
For chest auscultation, ask patient to sit upright and cough, to clear any sputum. Then move diaphragm of stethoscope from apices to bases of lungs. Always compare one lung to the other at the same site on opposite sides. Must ask yourself these questions:
Is there air entry to the bases?
If not where does it differ?
Does left=right?
Are the sounds normal?
Are there any adventitious sounds?

Pulse oximeters are designed to assess only pulsating blood vessels. This is why pulse oximeters can also measure a patient's pulse. However, must always manually check patient's pulse. Pulse oximetry measures the percentage of Hb in arterial blood that is saturated with O2.
Limited in cases of bright ambient light, poor perfusion, venous pulsation, and nail polish.
Asthma can lead to hypoxia, pulmonary hyperinflation (no Hering-Breuer reflex), and hypercapnia (severe acidosis). Hypercapnia is a late stage.
Following the lecture we had a tutorial. In this tutorial we learned about the different respiratory emergencies drugs:
Salbutamol: works on beta-2 receptors causing bronchodilation, without increasing the HR significantly. It is a fast acting, but short lasting  bronchodilator. Other names for it are Albuterol and Ventolin.
Ipratropium bromide: Anti-cholinergic drug causing bronchodilation. Same effect as Albuterol but has a different mechanism of action. It blocks receptors causing brochoconstriction. Another name for it is Atrovent.
Duolin: Ventolin + Atrovent. Double action. Causes bronchodilation and blocks bronchoconstriction. An alternative for this is to mix one vial of each ventolin and atrovent in the nebulizing mask chamber.
Epinephrine: Majorly acts on beta-1 receptors but has alpha receptor effects. Therefore, it increases the heart rate and force of contractility, vasoconstriction and a little bronchodilation. Also called Adrenaline.
Norepinephrine: Primarily acts on alpha receptors and causes vasoconstriction. Also called Noradrenaline.
Dexamethasone: A corticosteroid that maintains bronchodilation. It is also used to reduce bronchial swelling and mucus production. Other names include Solu-cortef and hydrocortisone.
Salmeterol: Slow acting but long lasting bronchodilator. Also called Serevant.
With using nebulizer drugs, usually we add 2mL of normal saline to avoid drying out the patient's mucosa.

Additional Readings

To further understand certain points i found a bit confusing, i conducted a search online and in my textbooks.
For the Pores of Kohn, i was a little lost to what they are. I found that they are the same as the alveolar pores, which connect adjacent alveoli to each other. This allows the air pressure throughout the lung to be equalized. They also provide alternate routes to any alveoli whose bronchi have collapsed (Marieb & Hoehn, 2014). Also, i found out through reading that the intrapleural pressure is negative relative to the intrapulmonary pressure. Therefore, the fluid in the pleural cavity is constantly pumped into the lymphatics. If this is disturbed and fluid accumulates in the pleural cavity, the pressure will become positive.Moreover, any condition that equalizes the intrapleural and intrapulmonary pressures will cause the lungs to collapse. This occurs in pneumothorax (Marieb & Hoehn, 2014).
I wasn't completely sure why breathing is more difficult in high altitudes. Through a literature search, this is what i found:
On sea level, the atmospheric pressure is 760mmHg, which plays a huge role in creating a pressure gradient that leads to breathing. In high altitudes, for example at the summit of Mount Everest, the atmospheric pressure decreases to around 53mmHg (San et al., 2013). This fall in pressure creates complications for the diffusion of air into and out of the lungs. Moreover, this fall in pressure means a decrease in the concentration of the atmospheric oxygen available. This leads to physiological adaptation changes. However, if the pressure changes too quickly, such as in a fest ascend, this can lead to illnesses (Imray et al., 2011).
I also looked up the drugs we discussed in the tutorial in the JRCALC (2013):
Salbutamol is presented as a 2.5mg/2.5mL and is nebulized with 6-8L/min of oxygen. It's use is indicated in patients with acute asthma attack, expiratory wheeze, exacerbation of COPD and as a secondary treatment for patients with shortness of breath due to LVF. There are no contraindications or maximum dose for this drug, however, if COPD is a possible cause then nebulization must be limited to six minutes (JRCALC,2013).
Ipratropium bromide presents as a 250mcg/ 1mL and it's use is indicated in acute severe asthma, acute asthma unresponsive to salbutamol, and exacerbation of COPD unresponsive to salbutamol. It has no contraindications and is nebulized with 6-8 L/min of oxygen. Moreover, in COPD limit nebulization is maximum six minutes. Also, for adults, the maximum dose is 500mcg/2mL (2 nebules) (JRCALC, 2013).
For both of the above drugs, if the patient is in a life-threatening state, time critical transport must be undertaken and nebulization given en route to hospital (JRCALC, 2013).
 Hydrocortisone: It's presented as a 100mg/1mL ampule of hydrocortisone diluted in either sodium succinate or sodium phosphate, or as a 100mg/2mL ampule of hydrocortisone sodium succinate  with water. It's indicated in patients with severe or life-threatening asthma and anaphylaxis. It's contraindicated in patient's that have an allergy to sodium succinate or sodium phosphate. This drug reduces inflammation and suppresses the immune response of the body. In asthma, it will reduc airway edema and mucus production. This drug is usually given through IV as a slow injection over a minimum of two minutes. In adults, the maximum dose is 1 ampule, whether it's the 100mg/1mL or the 100mg/2mL. However, in anaphylaxis, the maximum dose is 200mg/2mL of the 100mg/1mL ampule and 200mg/4mL from the 100mg/2mL ampule (JRCALC, 2013).
Dexamethasone: Presented as a 4mg/mL ampule. Used in moderate and severe croup and it's given via IV but is usually given orally. It's action is that it reduces subglottic inflammation. Usually given as 1 dose (4mg/mL). However, for infants of ages 1 month-12 months are usually given half a dose (2mg/0.5mL) (JRCALC,2013).
Adrenaline: Comes as a pre-filled syringe or ampule as 1mg/1mL (1:1,000) or as a pre-filled syringe containing 1mg/10mL (1:10,000) . It's use is indicated in patient's with anaphylaxis and life-threatening asthma. For patients taking tricyclic antidepressants, hald doses of adrenaline should be administered in case of anaphylaxis. Other than that there is no maximum dose. The usual dose for adults suffering anaphylaxis or life-threatening athma, is 0.5 mg/0.5mL of the 1:1,000 ampule, given every 5 mins (JRCALC, 2013).

Finally, i read some articles that were provided on the Moodle. The following are my notes from those articles:

  • Central cyanosis occurs as a result of prolonged hypoxia. It indicates a ventilation perfusion mismatch which implies serious heart or lung disease. This is observed in the lips, oral mucosa, and tongue. On the other hand, peripheral cyanosis indicates vasoconstriction, which could be a physiological or a pathological response (Massey & Meredith, 2010).
  • 75% of finger clubbing is associated with pulmonary pathology (Massey & Meredith, 2010).
  • When conducting a RSA, we assess the rate, depth and rhythm (Massey & Meredith, 2010).
  • Tachypnea in cardiac patients usually indicates moderate to severe cardiorespiratory disease and is an indication of a poor prognosis (Massey & Meredith, 2010).
  • Hyperpnea is characterized by rapid and deep respirations (Kussmaul's respirations) and are most common in DKA. These respirations are a compensatory mechanism to blow off excess carbon dioxide in the blood (Massey & Meredith, 2010).
  • Hyperventilation there is an increase in both rate and depth. On the other hand, tachypnea there is rapid, but shallow breathing. Cheyne-Stokes respirations gradually decrease and increase in a regular pattern, followed by a period of apnea. Biot's respiration is similar to Cheyne-Stokes respirations, except Biot's is irregular (Massey & Meredith, 2010). 
  • Purse lipped breathing is usually seen in patient's with emphysema. This acts a s a physiological PEEP (Massey & Meredith, 2010).
  • Expiratory bulging of the intercoastal spaces is common in patient's with a pneumothorax (Massey & Meredith, 2010).
  • When auscultating a patient's chest make sure to place the diaphragm of the stethoscope on the patient's bare chest. This is to avoid misinterpreting the rubbing sound of clothes as abnormal breath sounds (Meredith & Massey, 2011).
  • Adventitious sounds are extra sounds that are heard over the normal breath sounds. There are three groups: Crackles, wheezes and rhonchi. Wheezes result from air being forced through a narrow airway as a result of swelling and inflammation, usually seen in asthmatic patients. Rhonchi is a lower-pitched wheeze associated with secretions in the large airways, such as in bronchitis. Stridor is a high-pitched wheeze resulting from turbulent airflow in the upper airways. Crackles can be defined as fine or course. Can also be described as early inspiratory, late inspiratory, mid inspiratory, and expiratory (Meredith & Massey, 2011). 

References 
Imray, C., Booth, A., Wright, A., & Bradwell, A. (2011). Acute altitude illnesses. British Medical Journal, 343, 1-10. Doi: 10.1136/bmj.d4943
Joint Royal Colleges Ambulance Liaison Committee. (2013). UK ambulance services: Clinical practice guidelines 2013. Bridgwater: Class Professional Publishing.
Marieb, E.N., & Hoehn, K.N. (2014). The respiratory system. In E.N. Marieb & K.N. Hoehn (Eds.), Human anatomy and physiology (865-913). Essex, England: Pearson Education Limited.
Massey, D.,& Meredith, T. (2010). Respiratory assessment 1:Why do it and how to do it?. British Journal of Cardiac Nursing, 5(11), 537-541. Doi: 10.12968/bjca.2010.5.11.79634
Meredith, T.,& Massey, D. (2011). Respiratory assessment 2: More key skills to improve care. British Journal of Cardiac Nursing, 6(2), 63-68. Doi: 10.12968/bjca.2011.6.2.63

San, T., Polat, S., Cingi, C., Eskiizmir, G., Oghan, F., & Cakir, B. (2013). Effects of high altitude on sleep and respiratory system and theirs adaptations. The Scientific World Journal, 2013, 1-7. Doi: 10.1155/2013/241569

A Standout Moment
I was very confused about about the return of venous blood from the lungs via the pulmonary veins. This is because we always learned that pulmonary veins only carried oxygenated blood. However, now we were learning that it also carried deoxygenated blood and i didn't understand how that is possible. After reading and searching for over an hour online, i have found the answer. Simply, there are multiple anastomoses between the pulmonary and bronchial venous circulations. These anastomoses lead most of the systemic venous blood from the lungs to return to the heart via the pulmonary veins (Marieb & Hoehn, 2014). Therefore, the two venous circulations are linked and that is how deoxygenated blood reaches the pulmonary veins.

Reference
Marieb, E.N., & Hoehn, K.N. (2014). The respiratory system. In E.N. Marieb & K.N. Hoehn (Eds.), Human anatomy and physiology (865-913). Essex, England: Pearson Education Limited.

Biggest Impression

The thing that made the biggest impression on me this week was learning about the cricothyrotomy, since this is an important skill i might learn in the future. Also, learning about the different drugs in the tutorial made a big impression on me, since this directly relates to what i will be doing on the road as a future paramedic.