Sunday, February 7, 2021

Central Venous Catheterisation

CENTRAL VENOUS CATHETERISATION

 

Internal jugular vein approach (Seldinger's technique)

Position of patient 

Patient should be in head low position with head turned to face the left.

Procedure 

  1. Skin is cleaned with antiseptic. Neck can be extended by keeping a rolled towel or normal saline bag under shoulder.

  2. Local anaesthesia may be infiltered but that causes a wheal production which may hide the puncture site.

  3. Right internal carotid artery is palpated lateral to cricoid cartilage. 

  4. Triangle formed by two heads of sternocleidomastoid muscle and clavicle is located.  



  1. The heparinised needle with the syringe attached is inserted starting at the apex of the triangle keeping fingers gently over the internal carotid artery just lateral the pulsations at an angle 30 to 40 degree to the skin and advancing it downward in the direction of nipple on same side. 

Another way to gain access to IJV is to go behind the posterior head of sternocleidomastoid. 


  1. Blood is aspirated to confirm that needle is in the lumen of vein.


  1. The guide wire is threaded through needle into vein with J shaped end first.


  1. Needle is then removed.


  1. Dilator is passed over guide wire in the twisting motion to dilate the site of skin puncture. A small incision in the skin may be necessary to introduce the dilator.


  1. Dilator is removed and catheter is passed over guide wire.  

  2. Guide wire is removed. 

  1. After confirming blood can be aspirated freely the catheter is flushed properly with heparinised saline.

  1. The catheter is secured in place with suture and sterile dressing is given. 

 

        Post procedure X ray Chest is taken for confirming the position of the central line 

For accurate CVP measurement, the tip of the central venous catheter (CVC) should lie within the superior vein cava (SVC), above its junction with the right atrium and parallel to the vessel walls.


Other Sites  

  1. Subclavian Vein 

  2. Antecubital Vein 

  3. Femoral Vein 


Written by our guest author - Akash Davhale

Illustrations by Devi Bavishi

#Ae(ONE)INTERN

 


Arterial Puncture

ARTERIAL PUNCTURE (ABG ANALYSIS)

REQUIREMENTS:

Verbal consent, Gauge Piece, Syringe, 23G needle (for radial or brachial artery) OR 21-22G needle (for femoral artery), Sterile gloves, Antiseptic skin solution (generally ethanol is used), cotton, sterile gauze piece

Lithium heparin - 1-2 mL lithium heparin (1000 U/mL) should be aspirated into the syringe through another sterile needle and then pushed out; the plunger should be left depressed to allow the arterial blood flow to fill up the syringe. 

For arterial blood gas analysis, when heparin isn't available, do the following:

1) Collect blood in green vacutainer

2) Attach a new needle to the syringe

3) Aspirate blood from the vacutainer

4) Remove any air bubbles

PROCEDURE:

  • Take all aseptic precautions. 
  • First do Allen’s Test if planning to do a radial artery puncture to assess collateral circulation.

i. Firm occlusive pressure is held on both the radial artery and the ulnar artery  

ii. (see the first image below).The patient is asked to make a fist and open it, repeatedly till the palmar skin is blanched (see the second image below). Overextension of the hand or wide spreading of the fingers should be avoided, because it may cause false-normal results. The pressure on the ulnar artery is released while occlusion of the radial artery is maintained (see the third image below). The time required for palmar capillary refill is noted. (It should be ≤7 seconds normally).

 


  • Attach the heparinised syringe attached to another sterile 23G needle
  • Palpate the location of radial Artery
  • Wrist should be positioned in extension
  • Clean the puncture site for 30 sec
  • Warn the patient for sharp scratch
  • Insert the needle at 30- 45°
  • Aim towards maximum point if pulsation. Draw the plunger up once blood is seen in the syringe.




  • Remove the needle. 
  • Ask the relative or patient to continue to apply firm pressure over the puncture site for 5 minutes (to ensure haemostasis)
  • Recap the needle (not advisable because of the risk of needle-stick injury but done because special ABG syringes and needles are generally not available). For recapping, place the cap of needle over a surface like bed or table and then insert the needle inside the cap. DO NOT pick up the cover of needle to recap it (to prevent needle-stick injury). 


**When in doubt if you have had a needle prick or not, remove your gloves and fill it with water and look for any leak. If present, it is likely that you have had a needle prick.

CONTRAINDICATIONS:

  • An abnormal Allen test: Consider attempting to puncture at a different site. 
  • Local infection or distorted anatomy at the potential puncture site (eg, from previous surgical interventions, congenital or acquired malformations, or burns). 
  • The presence of arteriovenous fistulas or vascular grafts, in which case arterial vascular puncture should not be attempted. 
  • Known or suspected severe peripheral vascular disease of the limb involved. 
  • Severe coagulopathy
  • Anticoagulation therapy with warfarin, heparin and derivatives, direct thrombin inhibitors, or factor X inhibitors; aspirin is not a contraindication for arterial vascular sampling in most cases 
  • Use of thrombolytic agents, such as streptokinase or tissue plasminogen activator. 

COMMON SITES FOR ARTERIAL PUNCTURE: 

  • ABG sampling is usually performed on the radial artery because the superficial anatomic presentation of this vessel makes it easily accessible. 
  • Other sites include: femoral or brachial artery (present medial to tendon of biceps brachii).





PRACTICAL TIPS & TRICKS:

  • If arterial blood flow is not obtained, the operator might slowly pull back the needle; it is possible that the needle has gone through the vessel 
  • Initial arterial flow may subsequently be lost if the needle moves outside the vessel lumen; reidentification of the arterial pulse, using the nondominant middle and index finger, and repositioning the needle in the direction of the vessel could be attempted; avoid blind movement of the needle while it is inserted deeply in the patient’s body—pull it back to a point just below the skin, and redirect it to the arterial pulse felt with the other hand 
  • Puncture of venous structures can be identified by lack of pulsatile flow or dark-coloured blood, though arterial blood in severely hypoxemic patients can also have a dark appearance; if venous blood is obtained, removal of the needle from the patient might be necessary to expel the venous blood from the syringe
  • Excessive skin and abundant soft tissue may obstruct the puncture site; the operator can use the nondominant hand to smooth the skin, or an assistant can remove the subcutaneous tissue from the puncture site field 
  • Incomplete dismissal of heparin solution from the syringe could cause falsely low values for the partial pressure of CO; to avoid this, the operator should expel all heparin solution from the syringe before arterial puncture 
  • Incomplete removal of air bubbles can cause falsely elevated values for the partial pressure of oxygen; to avoid this, the operator should be sure to completely remove air bubbles from the syringe (vented plungers have an advantage over standard syringes in this regard)
  • Avoid puncture of the brachial artery or femoral artery in patients with diminished or absent distal pulses; the absence of distal pulses may signal severe peripheral vascular disease.


Written by our guest author - ABHISHEK GANACHARYA

Illustrations by Devi Bavishi

#Ae(ONE)INTERN

Automated Perimetry

 HUMPHREY FIELD ANALYSER (HFA)


1.Perimetry should be performed in a distraction-free environment, to enable the patient to concentrate on the perimetric test.

2.The perimeter is automatically calibrated each time it is turned on. Ideally, patient data (date of birth, refraction, etc.) are entered before the patient enters the room.


3.Before putting the patient onto the machine, the requirements of the test itself are clearly explained and the patient is instructed as follows.


4. Before fully positioning the patient, the eye not being tested should be covered with an eye patch that allows the patient to blink freely.



INSTRUCTIONS TO PATIENT

  • Perimetry tests your central and peripheral vision

  • Be relatively still once positioned

  • Always look straight ahead at the fixation target. Do not look around the bow for stimuli.

  • Press the response button whenever you see the stimulus 

  • The stimulus in a flash of light

  • Only one stimulus is presented at a time

  • The stimulus might appear from anywhere. Some stimuli are very bright. Some are very dim and sometimes no stimulus is presented. You are not expected to see all stimuli

  • Do not worry about making mistakes

  • Blink regularly to avoid discomfort. Don't worry about missing a point the device does not a measure while you blink

  • If you feel uncomfortable or are tired close your eye for a moment the test will automatically stop. The test will resume once you open your eye.

  • If you have a question, keep the response button pressed this will pause the test






5. The patient is positioned appropriately and comfortably against the forehead rest and chin rest. The lens holder should be as close as possible to the patient’s eye to prevent artefacts. 


6.The Analyser projects a series of white light stimuli of varying intensities (brightness), throughout a uniformly illuminated bowl.

 

 

7.The patient uses a handheld button that they press to indicate when they see a light. This assesses the retina's ability to detect a stimulus at specific points within the visual field. This is called retinal sensitivity and is recorded in 'decibels' (dB).

 

 

8.The Analyser currently utilises the Swedish Interactive Thresholding Algorithm (SITA); a complex mathematical formula which allows the fastest and most accurate visual field assessment to date.


For more information, see the youtube video (link below)

 https://youtu.be/TqL5KvvYJu4 


Written by our guest author - Jignesh Bhadarka

#Ae(ONE)INTERN

Blood Donation Criteria and Procedure

BLOOD DONATION

PRE-DONATION

HISTORY:

  • Men can donate safely once in every three months while women can donate every four months.

  • Age between 18 and 60 years 

  • The donor should be in a healthy state of mind and body.

  • Past one year - not been treated for Rabies or received Hepatitis B immune globulin

  • Past six months - not had a tattoo, ear or skin piercing or acupuncture, not received blood or blood products, no serious illness or major surgery, no contact with a person with hepatitis or yellow jaundice.

  • Past three months - not donated blood or been treated for Malaria. 

  • Past one month - had any immunizations.

  • Past 72 hours - had dental work or taken Aspirin 

  • Past 48 hours - taken any antibiotics or any other medications (Allopathic or Ayurveda or Siddha or Homeopathy)

  • Past 24 hours - taken alcoholic beverages

  • Presently - not suffering from cough, influenza or sore throat, common cold

  • Women should not be pregnant or breast feeding her child or menstruating.

  • No diabetes, chest pain, heart disease or high BP, cancer, blood clotting problem or blood disease, unexplained fever weight loss, fatigue, night sweats, enlarged lymph nodes in armpits, neck or groin, white patches in the mouth etc. 

  • No history of TB, bronchial asthma or allergic disorder, liver disease, kidney disease, fits or fainting, blue or purple spots on the skin or mucous membranes, received human pituitary - growth hormones etc.


EXAMINATION:

  • Temperature - Normal (oral temperature not exceeding 37.50 C)

  • Pulse - between 50 and 100/minute with no irregularities

  • Blood Pressure -Systolic 100-180 mm Hg and Diastolic 50 - 100 mm Hg

  • Body weight - not less than 45 Kg

  • Haemoglobin - not less than 12.5 g/dL- 

Procedure to measure Hb using CuSO4:

  1. Massage the finger to be pricked (preferably ring finger)

  2. Disinfect it

  3. Prick using disposable needle/ lancet

  4. Put the drop of blood in CuSO4 containing beaker

  5. If the blood drop sinks, Hb is more than 12.5, hence the person can donate blood (provided no other contraindication).



    PROCEDURE:

  • Identify donor and label blood collection bag and test tubes 

  • Ask the donor to state their full name.

  • Ensure that: 

  1. the blood collection bag is of the correct type;

  2. the labels on the blood collection bag and all its satellite bags, sample tubes and donor records have the correct patient name and number;

  3. the information on the labels matches with the donor's information.


  • Select a large, firm vein, preferably in the antecubital fossa, from an area free from skin lesions or scars.

  • Clean the site of venepuncture by alcohol and let it dry.

  • Perform phlebotomy using a 16-gauge needle, which is usually attached to the blood collection bag. Use of a retractable needle or safety needle with a needle cover is preferred if available, but all should be cut off at the end of the procedure.

  • Ask the donor to open and close the fist slowly every 10–12 seconds during collection.

  • Remove the tourniquet when the blood flow is established or after 2 minutes, whichever comes first. 

  • Ask the patient to squeeze a ball intermittently during the procedure.

  • Monitor the donor and the donated unit.

  • Remove the needle and collect samples.

  • Cut off the needle using a sterile pair of scissors. 

  • Collect blood samples for laboratory testing


POST-PROCEDURE:

DONOR CARE:

• ask the donor to remain in the chair and relax for a few minutes; 

• inspect the venepuncture site; if it is not bleeding, apply a bandage to the site; if it is bleeding, apply further pressure;

 • ask the donor to sit up slowly and ask how the person is feeling; 

• before the donor leaves the donation room, ensure that the person can stand up without dizziness and without a drop in blood pressure;

 • offer the donor some refreshments

BLOOD UNIT AND SAMPLES:

Transfer the blood unit to a proper storage container according to the blood centre requirements and the product 

• Ensure that collected blood samples are stored and delivered to the laboratory with completed documentation, at the recommended temperature, and in a leakproof, closed container


Reference: http://naco.gov.in/blood-transfusion-services-publications 


Written by our guest author - Harsh Jogi and Ayushi Gupta

Illustration by Devi Bavishi

#Ae(ONE)INTERN


 

Cardiotocography

 CARDIOTOCOGRAPHY


CTG machine has two sensors:

 

  • Cardio probe: placed on the mother’s abdomen at the foetal anterior shoulder to measure the foetal heart rate. 


  • Toco probe: placed on the mother’s fundus to record uterine muscle contraction.  

(Jelly is to be applied between the probe and the site of application of the probe)


 

CTG paper moves at rate of 3cm/min 

Therefore 1cm = 20 sec on x-axis

        

Also 1 cm = 10 bpm on Y axis


To be taken every 2 hours towards the end of pregnancy.


 When analysing a CTG look for 4 things: 

     1.      Baseline heart rate

     2.      Beat to Beat variability 

     3.      Accelerations

     4.      Decelerations 



  1. Foetal Heart rate: Normal: 110-160 bpm 

  2. Beat to beat variability:  Normal: 5-25bpm showing saw tooth pattern      

  3. Foetal accelerations: 

  • Abrupt increase in FHR above baseline. 

  • If a rise of 15 bpm persists for 15 sec or more but less than 2 mins is seen twice during a 20 min period then this is adequate contractions or REACTIVE (after 32 weeks). 

 

  1. Foetal decelerations: 

  • Decrease of 15 bpm in FHR for ≥15 seconds  

  • Time from onset of the deceleration to the lowest point of the deceleration >30 seconds in variable decelerations.





  • Early decelerations: Cause: pressure on the foetal head during labour (normal)

 

  • If late or variable decelerations are present, call a senior. 

 

    If all 4 parameters normal: REASSURING NST 

    If any 1 abnormal: SUSPICIOUS NST  

    If any 2 or more abnormal: PATHOLOGICAL NST 


 

If CTG is non-reassuring

  • Set up IV line

  • Start RL/Oxygen 

  • Give left lateral position

  • Call the resident

  • Stop oxytocin

  • Ask sister to give OT changes/scrubs  


Written by our guest author - Yash Bandewar and Anveshi Nayan

Illustration by Devi Bavishi

#Ae(ONE)INTERN

 

 

 

  


Friday, February 5, 2021

Sunday, January 31, 2021

Risk factors of Acute otitis media in child

 


Why Foot imaging is essential for Diabetic foot ulcer ?

Because osteomyelitis can arise without evidence of soft tissue infection due to neuropathy (diminished pain) and poor peripheral blood flow (diminished erythema, warmth, and purulence).  Therefore, foot imaging (eg, x-ray, MRI) is generally recommended for all diabetic foot ulcers that are:

How to identify Necrotizing surgical site infection ?

Saturday, January 30, 2021

OET Speaking

Speaking : (15-20 mins)

Speaking test is conducted on the same day for paper-based test while for the computer-based test it's one day before or after. How is it conducted? Speaking test has two role-plays.

OET Writing


Writing : (45 mins)

Unlike IELTS, in OET, writing test includes letter writing for 45mins. The letter can be a referral, a transfer or a discharge according to the given case notes. But mostly for doctors ,it's a referral letter. Out of the 45 mins first 5 mins are to read the case notes and only after that we are allowed to write the letter.