Iv cannulation sites


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Iv cannulation sites

  1. 1. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationVenepuncture and IV CannulationMedical StudentPractical Skill SessionPage 1 of 16
  2. 2. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationContentsAnatomy And Physiology 3Structure Of Veins 4Superficial Veins 5Antecubital Fossa 7Veins 7Arteries 7Patient Assessment 11Factors Influencing Vein Choice 11Condition Of Vein 11Improving Venous Access 11Site Preparation 12Infection Control 12Venepuncture 13Procedure Of Venepuncture 13Equipment 13Procedure 13Intravenous Cannulation 14Patient Assessment 14Cannula Selection 14Methods To Reduce Pain 14Cannulation Procedure 15Equipment 15Cannulation 15Securing The Cannula 16Care Of The Cannula 16Complications 16Resiting Or Removal Of Cannula 16Page 2 of 16
  3. 3. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV Cannulation•Anatomy and Physiology• Structure of veins• Superficial veins• Antecubital FossaPage 3 of 16
  4. 4. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationSuperficial Veins Of The Upper LimbCephalic veinMedian Cubital vein Basilic veinAccessory Cephalic veinCephalic vein Superficial Median vein of the forearmPalmar Venous PlexusPalmar Digital veinsPage 4 of 16
  5. 5. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationThe Forearm VeinsThe Cephalic VeinForms from a confluence of veins at the base of the thumb and passes upward along the radial(lateral) aspect of the forearm to enter the lateral part of the antecubital fossa.PROs.• Readily receives a large cannula and is therefore a good site for blood administration.• Splinted by the forearm bones.• Cannula is easily secured.CONs.• Can be more difficult to cannulate than the metacarpel veins.• May be confused with an aberrant radial artery.The Basilic VeinForms from a confluence of veins on the postero-medial aspect of the wrist and passes upwardslightly posterior to the ulnar (medial) border of the forearm but winds round over the ulnar to enterthe medial aspect of the antecubital fossa.PROs• A large vein that is frequently overlooked in the hunt for veins.CONs.• Requires awkward positioning of the limb to gain access to the vein.• The vein tends to roll away when you attempt to cannulate it.• Sites prone to phlebitis.• Cannula port gets caught on sheets.The Median Veins Of The ForearmMany Veins with vary variable courses.Page 5 of 16
  6. 6. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV Cannulation•Metacarpal VeinsPROs• Easy to see and palpate veins.• Splinted by metacarpal bones.• Allows use of more proximal veins in the same limb should the cannula need to be re-sited.• Cannula is easily accessible in the theatre environment.CONs• Active patients may dislodge easily.• Dressing may be compromised by handwashing.• May be more difficult if the skin is thin and friable.• Flow can be affected by wrist flexion or extension i.e. A POSITIONAL VENFLON.Basilic veinCephalic veinDorsal Venous PlexusDorsal metacarpal veinsDorsal Digital veinPage 6 of 16
  7. 7. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationThe Veins Of The Antecubital FossaAt least 3 major veins;Cephalic VeinA continuation of the vein upward from the antero-lateral aspect of the forearm onto the antero-lateral aspect of the arm over the biceps muscle. From here it passes up to the deltoid muscle where,at a variable point, it passes through the superficial fascia to join the brachial vein to form theaxillary vein.Basilic VeinA continuation of the vein from the antero-medial aspect of the forearm. It may pierce thesuperficial fascia in the antecubital fossa and join the deep veins to form the brachial vein or it maytraverse the antecubital fossa and pierce the fascia at a variable point on the medial aspect of thearm.Median VeinThere may be more than one ‘median’ vein in the antecubital fossa.They are formed by the convergence and divergence of branches of the 3 forearm vems.PROs• Large veins and so they will readily accept a large cannula.• Do not "shut down" as quickly as the more peripheral veins.• FIRST CHOICE IN THE EMERGENCY SITUATION.CONs• Can be very positional due to elbow flexion/extension.• Can be very uncomfortable for the patient due to elbow flexion/extension.• Care must be taken not to cannulate the brachial artery.•Page 7 of 16
  8. 8. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationThe Antecubital Fossa.•Brachial ArteryBasilic VeinBiceps Medial CutaneousNerve of ForearmBrachialisMed. Cut. N ofForearm and LoopLat. Cut. N of ForearmMedian NBrachioradialisMedian Basilic VeinMedian Cephalic VeinBicepital AponeurosisCephalic Vein DeepCommunicatingVeinPronator TeresSuperficialMedian VeinPage 8 of 16
  9. 9. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV Cannulation•VeinsDefinition• A collecting system of vessels for blood RETURNING from the peripheries to the heart.• All veins, except for the pulmonary veins, carry deoxygenated blood and carbon dioxide.There are 3 venous systems;Systemic:Drains blood from all the organs, except for the lungs and G.I. tract back to the right atrium.This system can be sub-divided into a SUPERFICIAL and DEEP system according to theveins relationship to the superficial fascia of the body.Pulmonary:Drains oxygenated blood from the lungs to the left atrium.Portal:Drains blood from the G.I. tract between the gastro-oesophageal junction and the recto-analjunction and carries it to the LIVER. The blood then drains into the systemic system via thehepatic veins.All veins, except for the superficial systemic veins, have a similar pattern of distribution as arteries,e.gFemoral Vein and ArteryCarotid Artery and Internal Jugular Vein (external jugular is a superficial vein).Structure3 layers like arteries, but;• There is much less muscle in the media which means the wall is much thinner and ismuch more easily distended or collapsed by pressure.• The intima is folded up to form venous valves.Despite its thinner media the vein retains significant sympathetic innervation and so significantVENOCONSTRICTION can occur leading to collapsed or ‘SHUT DOWN’ veins.ArteriesDefinition• The vessels carrying blood AWAY from the heart.• All arteries, except the PULMONARY arteries, carry oxygenated (bright red) blood.Structure3 layersIntima: Consists of an ENDOTHELIUM surrounded by a thin layer of elastic tissue.The endothelial cells are flat and line the vessel to promote the smooth laminarflow of blood. They also release chemical substances involved in the initiation ofclotting. More recently it has been discovered that they synthesise and releasenitric oxide, a -simple molecule, involved in many physiological and pathologicalprocesses.Media: A thick layer of intermingled smooth muscle cells and elastic fibres.Page 9 of 16
  10. 10. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationIts function is to distend as the heart ejects blood into the arterial tree and then tocontract back down when the heart goes into diastole. This maintains the normalcalibre of the vessel and also promotes forward flow of blood during diastole.This effect can beseen on an arterial line or pulse oximeter trace as a "bump" onthe downstroke of the trace.Adventitia: A tough fibrous layer.This protects the artery and merges in with the surrounding connective tissuPage 10 of 16
  11. 11. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationPatient AssessmentFactors Influencing Vein ChoiceAge of patientPrevious uses and condition of the veinsClinical status of patient e.g. Dehydrated, shock, amputee, mastectomy, oedema, thrombocytopenia,CVAOther clinical procedures required during admissionType and length of treatmentMedications: warfarin, heparin, steroidsPatient preferencePatient co-operation, previous experiencesTry to use non dominant armSites: median antecubital veins, forearm veins, dorsum of hands and in difficult patients’ dorsum offoot.Condition Of VeinA good vein is:• Bouncy• Soft• Refills when depressed• Visible• Has a large lumen• Well supported• StraightA void veins which are:• Thrombosed / sclerosed / fibrosed• Inflamed / bruised• Hard• Thin / Fragile• Mobile / tortuous• Near bony prominences, painful• Areas or sites of infection, oedema or phlebitis• In the lower extremities (unless none else available)• Have undergone multiple previous puncturesImproving Venous Access• Application of a tourniquet promotes venous distension. The tourniquet should be tightenough to impede venous return but not affect arterial flow.• Lower the extremity below the level of the heart• Use muscle action to force blood into the veins - e.g. open and closing of the fist• Light tapping of the vein• Apply warm compresses or immerse limb in bowl of hot water to increase vasodilatation• Consider GTN PatchPage 11 of 16
  12. 12. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationSite PreparationPosition the patient appropriately to facilitate the procedure, you may need help.Choose an appropriate siteInfection ControlAsepsis is vital as the skin is breached and a foreign object is introduced into a sterile circulatingsystem. The main sources of microbial contamination are:• Cross infection from practitioner to patient• Skin floraHands should be clean, having been washed prior to the procedure, and an alcohol solution/gelapplied to the hands before donning a pair of gloves. Gloves will protect your hands againstcontamination from the patients blood, and will provide some additional protection in the case of aneedle-stick injury by wiping some of the contaminating blood from the needle prior the skinpuncture.The site of the proposed venepuncture should be wiped with an isopropyl alcohol 70% swab (e.g.mediswab) and this should be allowed to dry (for a minimum of 30 seconds) prior to proceedingwith venepuncture. This will clean any gross contamination of the patients skin and will reduce thepatients skin flora at the site of puncture.The skin must not be touched or the vein re-palpated once the skin has been cleaned,Sharps should be immediately disposed of in a sharps container, and no needles should be re-sheathed.This is to avoid needle-stick injuries to you or others involved in the patients care, lowering theincidence of blood borne viral illnesses (In particular Hepatitis B/C and HIV)Use a no-touch technique for any part of the needle or cannula which is to puncture the patientsskin.Page 12 of 16
  13. 13. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationVenepunctureProcedure Of VenepunctureEquipment• Tray• Mediswab• Tourniquet• Small adhesive dressing.• Sharps Container• Gloves• Isopropyl alcohol 70% solution hand rub solution• ‘Vacutainer’ systemneedle, holder, appropriate evacuated tubesOrSterile syringe, Sterile needle, Appropriate evacuated tubeProcedure1. Assemble equipment2. Inform patient of procedure3. Select a suitable vein - e.g. the vein in the antecubital fossa or forearm4. Palpate the vessel to exclude the possibility that it is an artery5. Apply a tourniquet medial to selected site6. Put on gloves7. Cleanse skin with alcohol wipe8. Fix the vein by applying pressure to skin over the vein, approximately two inches belowvenepuncture site9. Leaving the coloured shield on the needle, screw it onto the holder10. Remove shield and approach the skin, with needle bevel uppermost at an angle of 35~45degrees11. When the needle has penetrated the skin, realign it with the vein and reduce the angle to about15 degrees12. Introduce the tube into the holder, with middle and forefmger supporting flange of the holder,push the tube with the thumb to the end of the holder, puncturing the diaphragm of thestopper.13. As soon as blood starts to flow into the tube, remove the tourniquet.14. When blood flow ceases, gently disengage tube from holder - if more samples are required,repeat from stage 1215. Tubes with additives should be gently inverted to mix contents - shaking may causehaemolysis.16. Always draw samples without additives first.17. Place a clean swab or piece of cotton wool over the needle as it is gently withdrawn, pressureshould be applied to the site until haemostasis occurs, at which time an adhesive dressing isapplied. It is not recommended that the patient bend their arm as this increases theintravascular pressure.18. Ensure all samples are clearly labelled19. Never re-sheath needles as this is the commonest source of needles tick injury.20. Ensure all sharps are disposed of safely and examine holder for any contamination, in whichcase it should be discarded - in normal practice the holder does not come into contact withblood products and is intended for multiple use.Page 13 of 16
  14. 14. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationIntravenous CannulationPatient Assessment Site SelectionSite selectionInspect both arms (and legs if required)Try to use non dominant armPalpate the veinDoes it bounce? Make sure it does not pulsate. Is it thrombosed?, will it take the size of cannulaneeded? Will you be able to secure the cannula easily? Does the venous drainage look normal (isthere evidence of fracture, extravasation from previous proximal cannula, lymphoedema orparalysis? Have you avoided a joint area which may need to be splinted?Cannula SelectionWhen considering the choice of cannula consideration should be given to the following: minimisingdiscomfort to the patient, ensuring good flow rates, and easy insertion with no tissue reaction to thecannula. It should be of the smallest practical size to provide the required fluid regimen and takeinto account the size of vessel cannulated, the time scale of the proposed administration of infusionand the viscosity of the fluid to be infused.Flow through the cannula is proportional to:The fourth power of the radius i.e. 2xr=16xflowThe pressure difference across the cannula (i.e. pressurised infusions flow faster)Flow through the cannula is inversely proportional to:The length of the cannulaThe viscosity of the fluid being administeredColour Size mm Max flow/min (length) Common usesOrange/brown 14g 2.0 265mllmin (l=42mm) Rapid transfusions, bloodGrey 16g 1.7 170mllmin (l=42mm) As aboveGreen 18g 1.2 90mllmin (l=40mm) IV maintenance fluidsPink 20g 1.0 55mllmin (l=32mm) IV drugs/infusionsBlue 22g 0.8 25mllmin (l=25mm) Paediatrics/difficult veins.Methods To Reduce PainGood technique, skill and vein selectionLocal anaesthetic infiltrationTopical anaesthesia e.g. EMLA and Amethocaine gelPage 14 of 16
  15. 15. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationCannula ProcedureEquipment• IV cannula• Alcohol wipe• 2ml syringe• 25g needle• 5ml amp of 1 % lignocaine solution• Adhesive dressing for fixation of cannula• Tourniquet• Sharps Container• Gloves• Isopropyl alcohol 70% solution hand rub solutionCannulation1. Assemble equipment2. Inform patient of procedure3. Select a suitable vein - e.g. the vein in the forearm or dorsum of the hand4. Palpate the vessel5. Apply a tourniquet medial to selected site6. Put on gloves7. Cleanse skin with alcohol wipe8. Infiltrate skin over proposed puncture site with 1 % lignocaine solution9. Hold patients hand with your non-dominant hand, using your thumb to keep skin taut, andanchor vein to prevent it rolling10. Inspect needle tip to ensure cutting edge is smooth and intact. Place cannula needle in linewith direction of the vein, and a few mm below proposed entry site, with bevel pointingupwards to reduce tissue trauma11. At a low angle, gripping the cannula as in demonstration, insert the needle through the skinand into the vein, as identified by the flashback of blood into the chamber at the hub of thecannula12. Once inside the vein advance the needle 2-3mm in a parallel motion to ensure the cannula isalso in the vein13. Withdraw the needle stylet (holding the cannula steady) about 5mm to avoid piercing theposterior vein wall, there should be a further flashback of blood along the shaft of the cannulaand now advance the cannula into the vein.14. Never re-insert the stylet as this can shear off the end of the cannula and cause an embolus.15. Release the tourniquet16. Place a finger over the vein above the tip of the cannula to prevent bleeding as you nowremove the needle stylet.17. To separate the needle and the lure lock cap, hold the cap between thumb and third finger anduse your index finger of the same hand to push on the guard, away from you.18. Place the cap on the cannula and safely dispose of the needle19. Flush the cannula with heparinised saline to ensure cannula patency20. Cover the insertion site and immobilise the cannula by applying a sterile non-occlusivedressing.Page 15 of 16
  16. 16. University Section of Anaesthesia, Pain & Critical Care Medicine Clinical Skills in Venepuncture & IV CannulationSecuring The CannulaIt is important to secure the cannula to prevent mechanical phlebitis.This can be done with clean tape or a special adhesive dressing. Care should be taken to avoid theinsertion site.If the device is located over a joint, the joint should be immobilised and splinted to preventmovement and dislodgement of the cannula.Care Of The CannulaOnce sited the cannula should be flushed with either normal saline or heparinised saline. The siteshould be regularly inspected for signs of phlebitis.Peripheral cannulae should be re-sited every 48-72 hours to reduce the risk of phlebitis, but thismay be difficult in patients with difficult veins.ComplicationsIf Cannulation is unsuccessful do not reinsert stylet into cannula as it may shear off the cannula andlead to catheter embolism.Chemical irritation from the infusion may cause phlebitis and pain. An acidic pH and highosmolality are particularly likely to cause problems. Dilute solutions appropriately for peripheraladministration. Where osmolarity of the solution exceeds 600molmolal avoid peripheral venousadministration and give into a central vein. Buffering of solutions prior to administration with smallquantities of phosphate or bicarbonate buffers up to a pH of 7 will reduce the incidence of phlebitisfrom chemical irritation but introduces the risk of making the environment more suitable forbacterial contamination.The cannula may block from thrombus formation if it is not kept flushed.Extravasation occurs when cannula pulls out of the vein, or becomes partly occluded by venousconstriction causing back flow of the infusate through the puncture site into surrounding tissues.The patient may complain of tightness, burning and discomfort around the iv site and there may beswelling and blanching of the tissues. Treatment is to stop infusion immediately and re-site cannula.Haematoma is formed when blood leaks into the tissues surrounding the insertion site after failureto penetrate vein properly during insertion, puncture of posterior wall of vessel or removal of thecannula. Treatment is to apply pressure to puncture site for 3-4 minutes.Infection: This can cause phlebitis and thrombus formation. It is prevented by good aseptictechnique, keeping the dressings clean and not leaving the cannula in for any longer than necessary.Phlebitis: This is acute inflammation of the intima of the vein. It is caused by mechanical andchemical irritation, or by microscopic particles that may contaminate infusion fluids. Clinicallythere is erythema over the cannulated vein and surrounding skin and it is warm to touch. Treatmentis to remove the cannula. Thrombophlebitis. This is acute inflammation of the intima of the veinwith the formation of a thrombus.It is commonly associated with infection at the site of the cannula and may present with raisedwhite cell count, lymphadenopathy and positive blood cultures. There may be pus visible aroundskin entry site. Treatment is to remove cannula and commence parenteral antibiotics.Resiting Or Removal Of CannulaCannulae should not remain in situ for any longer than necessary to reduce the risks of infection.Consideration should be given to resiting them after 48-72 hours.When removing the cannulae, pressure should be applied to the site for at least a minute and the siteshould be occluded with a sterile dressing.Page 16 of 16