Preoperative Medications & Anaesthesia PDF

WEEK TWO > Purpose of preoperative medications - Drugs used prior to the administration of an anaesthetic agent to facilitate a safe anaesthetic - Depending on patient circumstances and prescription, premedications may be used to; Provide analge...

WEEK TWO > Purpose of preoperative medications - Drugs used prior to the administration of an anaesthetic agent to facilitate a safe anaesthetic - Depending on patient circumstances and prescription, premedications may be used to; Provide analgesia Facilitate induction of anaesthesia Prevent nausea and vomiting Relieve apprehension and anxiety Promote sedation and amnesia Prevent autonomic reflex response (eg, sweating and urination) Decrease anaesthetic requirements Decrease respiratory and gastrointestinal secretions - Frequently used preoperative medications include; Class: Drug: Purpose and effects: Benzodiazepines - Midazolam - Reduce anxiety - Diazepam - Induce sedation - Lorazepam - Induce amnesia Opioids - Morphine - Reduce anxiety - Pethidine - Provide analgesia - Fentanyl - Decrease amount of anaesthetic used Histamine receptor - Cimetidine - Increase gastric pH antagonists - Famotidine - Decrease gastric - Ranitidine volume Antacids - Sodium citrate - Increase gastric pH Antiemetics - Metoclopramide - Increase gastric - Droperidol emptying - Decrease nausea and vomiting Anticholinergics - Atropine - Decrease oral and - Glycopyrrolate respiratory secretions - Hyoscine - Prevent bradycardia - Less common - Either IM, IV intranasally or PO (oral usually preferred) - Before pre med given, LAST MINUTE QUESTIONS, consent forms verified - Usually given 30-90 minutes before surgery or IV in holding bay or in the OT - Paediatrics or needle phobias – emla cream – local anaesthetic (lignocaine and prilocaine) > Critical thinking point  - You are caring for an 18-year-old patient who has come into hospital for a surgical procedure and has a known needle phobia. The patient asked if they can apply Emla cream in advance (numbing cream) and you informed the patient that this will be okay. You report back to the nurse you are shadowing, and they tell you that they don’t have time to wait for the cream to work (it usually takes 45mins - 1hr). You accompany the nurse who hurries back into the room, and you witness them tell the patient that the numbing cream “doesn’t help much” and they were too busy so need to “do it now without the cream”. You can see that the patient is visibly distressed at this decision. > Overview of intraoperative nursing care Holding bay - Identify the patient using identifiers - Verify the surgical site, surgical procedure, consent and patient understanding of the procedure - Assess level of consciousness (GCS), assess Integumentary system and review medical records During surgery - Ensure the sterile field remains uncontaminated, verify that all surgical instruments are accounted for, and position the patient correctly to avoid pressure injuries. Maintain safety with electrical equipment and lasers, administer medications correctly, and monitor the patient for any changes in vital signs or blood loss. Offer reassurance to the patient before general anaesthesia or during spinal/epidural procedures. Communicate any issues to the multidisciplinary team (MDT) and take immediate action to prevent complications. Completion - As the procedure ends, stop inhaled anaesthetics and give reversal agents if muscle relaxants were used. After anaesthesia, evaluate the Glasgow Coma Scale (GCS) and vital signs, comparing them to preoperative levels to check for any deterioration. Administer medications safely, monitor the patient's airway, breathing, and circulation, and prepare a detailed medical and nursing report for transfer to the Post-Anesthesia Recovery Unit (PARU), Post-Anesthesia Care Unit (PACU), or Recovery Room. > Overview of perioperative personnel Nursing: Other roles: - Anaesthetic nurse/ technician - Surgeon and surgical assistant - Circulating/ scout nurse - Anaesthetist - Instrument/ scrub nurse - Pharmacist - Post anaesthesia care unit (PACU) nurse - Perfusionist-cardiac bypass machine - Floor/ shift coordinator; SDN; NUM - Orderly/PCA - Perioperative surgical nurse assistant - Orthopaedic technician (PSNA) - Radiographer - Advanced roles; Nurse practitioner; - CSSD staff – cleaning, checking, Nurse endoscopist; Nurse Cystoscopy; packing, sterilising Cosmetic Nurse - Support staff-clerical, cleaning > Positions during the procedure > Anaesthetic Nurse - Participate in patient identification and - Understands, prepares and assists in other processes outlined in the any anaesthetic emergencies. ‘Surgical Safety Checklist’. - Monitors airway devices, ETT cuff - Advocate for the patient. measurements, invasive pressures and - Collaborate with and assist the all other equipment relating to patient anaesthetist. observations. - Anticipate and provide equipment and - Measures and documents blood, fluid supplies. and other loss in the patient's fluid - Prepares and checks the anaesthetic balance chart. machine, equipment, IV and arterial - Assists with patient transfer before and lines as required. after surgery. - Assist in maintaining patient airway. - Collaborates with post-anaesthesia care - Applies monitoring devices. unit staff. > Circulating Nurse (Scout Nurse) - Participates in processes outlined in the - Ensures correct handling and labelling surgical safety checklist. of surgically removed human tissue and - Advocates for the patient. explanted items. - Assists to prepare the room ensuring - Performs and documents the surgical that all supplies and equipment are count with the instrument nurse. available. - Documents intraoperative nursing care - Anticipates the needs of the surgical and medications used by the operative team before and during surgery. team and patient outcomes. - Monitors the draping procedure and the intraoperative environment for breaches in aseptic technique and initiates corrective action. - Prepares, records, labels and sends blood pathology. > Instrument Nurse (Scrub Nurse) - Participates in the process outlined in - Assists with skin prep and draping of the surgical safety checklist the surgical site - Advocates for the patient - Passes equipment to the surgeon and - Prepares instrument table and assistants by anticipating their needs organises sterile equipment in a - Performs surgical count with the functional manner for surgery circulating nurse - Anticipates needs of the surgical team - Ensures correct handling and labelling prior to & during surgery of surgically removed human tissue and - Works directly with surgical team explanted items - Adheres to, and maintains, surgical - Documents intraoperative nursing care aseptic technique throughout the & patient outcomes. procedure - Monitors breaches in surgical aseptic technique & initiate corrective action > The Recovery Room Nurse – PACU/PARU/Recovery - Maintenance of the patient’s airway, breathing and circulation - Pain control - Relief from nausea and vomiting - Assessment of the wound site - Management of fluid balance - Documentation > Types of anaesthesia: General (GA) - Loss of all sensation and consciousness - All protective airway reflexes of cough, swallow and gag are suppressed - Acts by blocking the awareness centre in reticular activating system (RAS) in brain so amnesia, analgesia, hypnosis (artificial sleep), and relaxation occurs - Administered via IV, inhalation of gases with facemask, or through laryngeal mask (LMA) or endotracheal tube (ETT) - Three phases of GA → INDUCTION: Begins with administering of anaesthetic until patient ready for positioning or surgical prepping (INTUBATION) → MAINTENANCE: Until near completion of the procedure → EMERGENCE: Starts as the patient begins to “emerge” and ends when the patient is ready to leave the OT. (EXTUBATION) → RECOVERY: From anaesthesia can be considered a 4th phase of GA Benefits: Disadvantages: - Suppression of physiological and - Close monitoring of neurological, emotional stress of surgery and respiratory, and cardiac functions feeling of pain when patient is unconscious as it - GA can be adjusted for length of depresses these systems surgery, titrated for age and - Patients often more nervous about physical status GA than surgery due to loss of control - IV technique examples include; → Introduction agent - propofol with 30% to 40% 02 and Nitrous oxide (N20)  → Amnesic drug such as midazolam → Analgesic such as fentanyl or morphine sulphate → A muscle relaxant (causes temporary paralysis) such as rocuronium > Types of anaesthesia: Regional anaesthesia - Regional analgesia: Temporary interruption of the transmission of nerve impulses to and from a specific area or region of the body. The person loses sensation and movement in a targeted area of the body but remains conscious - Topical (surface) anaesthesia: Applied directly to skin and mucous membranes - Local anaesthesia (LA): Injection of local anaesthetic into specific area eg; sutures, obtaining biopsy, removing lesion-minor surgical procedures - Peripheral nerve blocks - Intravenous Block (Bier’s block) - Central nerve blocks (epidurals and spinal) - Conscious sedation - can be used alone or with regional anaesthesia for some tests and procedures – person remains awake, with patent airway eg; midazolam for sedation, with an analgesic like fentanyl/morphine - Procedure examples: Endoscopes, and some angioplasties > Types of local anaesthetics - What is it? Local anaesthetics are drugs that block conduction when applied locally to nerve tissue. The block produced is reversible. - How does it work? Interrupts generation of nerve impulses by altering the flow of sodium into nerve cells through cell membranes - Some can be topical (surface application) eg; aerosol or spray (co-phenylcaine forte spray), nebuliser, gels, ointments (ELMA) Lignocaine Quick - short acting Bupivacaine Slow - long acting Ropivacaine Slow - long acting Amethocaine Topical Prilocaine IV > Regional anaesthesia - Peripheral nerve blocks: Where the (LA) is injected into the vicinity of a nerve trunk or group that supplies sensation to a small area of the body (eg; Large = brachial plexus block, pudendal block for obstetric surgery & Small = single nerve eg; facial nerve) - Intravenous Block (Bier’s block): Is used most often for procedures involving the arm, wrist and hand. An occlusion tourniquet is applied to the extremity to prevent infiltration and absorption of the injected IV agent beyond the involved extremity, and the duration of surgery is time critical because an occlusive tourniquet is in place - Central nerve blocks: (Eg spinal or epidural) the local anaesthetic (LA) is injected into spinal roots where they emerge from the spinal canal. SPinal blocks involve LA into the subarachnoid space, whilst epidural anaesthesia involve LA and/or opioid to epidural space (outside dura mater) > Nursing management for local and regional anaesthetic  - Obtain history of prior anaesthetic and outcomes - Check fasting status - some patients may require fasting if they are high risk of being converted to GA - Monitor vital signs - Observe for signs of autonomic nervous system blockage eg;hypotension, bradycardia, nausea and vomiting and report - Monitor and report for systemic absorption or toxicity – block is “too high” – patient may experience tingling in arms and hands, dyspnoea or apnoea - Supervise ambulation post epidural and spinal anaesthesia > Airway management and considerations - Revise anatomy of the airway for use and management of artificial airways - When patient is unconscious- muscle tone of upper airway is lost, causing tongue and epiglottis to fall back on the posterior wall of pharynx obstructing the airway - Artificial airways e.g. guedels (oropharyngeal airway) helps prevent airway obstruction; nasopharyngeal airways can be used for oral/dental procedures- requires lubricant and inserted through nose - Chin lift and jaw thrust also required, often with airway adjuncts - Nurses must be familiar with managing airways, with artificial airway options and for troubleshooting. - Correct techniques important to prevent complications e.g. C’ grip (hand) when holding face mask insitu to ensure patent airway and adequate seal (see readings) > Preoperative airway assessment > Airway equipment 1. Laryngoscope handle 2. Curved laryngoscope blade 3. Straight laryngoscope blade 4. Endotracheal tube (ETT). 5. Stylet – a probe that assists with Intubation 6. Large oral airway (guedels) 7. Small oral airway (guedels) 8. Nasopharyngeal airway 9. Yankauer sucker 10. McGill Forceps – aid passage of endotracheal tubes 11. Face mask-sized for patient 12. 10 ml Syringe 13. Carbon dioxide detector / filter 14. Tracheal light 15. Airway Bougie – similar in function to a stylet but more elastic 16. Laryngeal mask airway (LMA) or supraglottic airway device 17. Ambu bag or bag valve mask (BVM) > Anaesthetic induction - Apnoea is induced - Eyelash reflex lost – eyes taped shut - Ventilation via bag valve mask (BVM) → Chest rise and fall = airway patency - Position head or insertion of an oral/nasal airway to maintain a patent airway > Guedel’s (Oropharyngeal) airway and Nasopharyngeal airway (ADJUNCT AIRWAY) > Laryngeal Mask Airway (LMA)/ Supraglottic airway (DEFINITIVE AIRWAY) Intubation with LMA: - May be inserted without a muscle relaxant - Minimises aspiration risk - Short procedure use-not suitable for all patients - Surgical site not in head or neck area - Inserted in mouth, positioned over the larynx and inflated-no need to visualise vocal cords > Laryngoscopes - Used for performing ETT intubations. A laryngoscope consists of a blade, of varying sizes (1 to 4), which includes a fibre optic light source, and a handle, which contains the power source for the light > Endotracheal Tube (ETT) - Intubation (DEFINITIVE AIRWAY) Aim: - Facilitate ventilation and prevent aspiration - Different sizes available (7.5mm for women, 8 - 8.5mm for men) Benefits: - Maintenance of a clear airway under difficult circumstances - Operations on the head, neck, mouth, throat and nose - Protection of the trachea - Facilitation of tracheobronchial toilet - Controlled ventilation > ETT insertion Progress: - Surgical and anaesthetic time out - Induction of anaesthetic - Patient positioning: “Sniffing” position → Neck flexed, head extended - Pass ETT through vocal cords - Inflate cuff → Ensure gas does not rush out patient’s mouth when ventilated → Reduced risk of aspiration → Cuff pressure = 30mmHg - Once position confirmed, secure ETT with cotton tape record position at teeth Confirm placement: - Look, listen and feel for breath sounds - End tidal CO2 trace (waveform capnography) - Monitor oxygenation > Rapid sequence induction (RSI) Why: - To reduce risk of pulmonary aspiration of acid stomach contents Indications for: - Unknown fasting time (emergency case) - Pregnancy - Hiatus hernia - Bowel obstruction - GI bleeding - Gastric reflux - Trauma sustained after eating (aspiration event) How – Cricoid Pressure/ Sellick’s Manouvre: - Cricoid cartilage of the larynx - Digital pressure applied to cartilage - Oesophagus compressed by posterior cricoid cartilage and vertebra (C6) - Prevents regurgitation and aspiration (closes oesophagus which lies behind it) - Released when ETT cuff is inflated and only when asked to do so > Airway obstructions and complications – Medical Emergencies - Examples include; → Obstructive Sleep Apnoea (OSA) post op – PACU - patient may need own device post op (CPAP) → Aspiration - Decreased throat reflexes – under GA; Acidic gastric contents enter the lungs; Residual effects impede lung function and gaseous exchange; Oedema, alveoli collapse, Hypoxia → Anaphylaxis - Tracheostomy formation and care - Acute airway obstruction is a medical emergency-insertion of a tracheostomy or similar airway may be required - Tracheostomy – A surgically created stoma (opening) in the trachea, performed to establish an airway: → Bypassing an upper airway obstruction → Facilitating secretion removal → Allowing for long-term mechanical ventilation > Catastrophic events in the operating theatre Anaphylactic reactions: Malignant hyperthermia: - Manifestation may be masked by - Muscle rigidity anaesthesia - Tachycardia - Vigilance and rapid intervention are - Tachypnoea essential - Elevated body temperature - 41 - Symptoms include hypotension, degrees or higher (NOT an early sign) tachycardia, bronchospasm and - Respiratory and metabolic acidosis pulmonary oedema - Ventricular arrhythmias - Antibiotics and latex main instigators - Can result in cardiac arrest and death - Situational Awareness (SA) - Importance: → Refers to the way in which people collect (perceive), interpret (comprehend) and use information to inform decision making (projection) → In a healthcare environment, nurturing this skill can help to prevent errors and improve patient outcomes → Individual and contextual factors and cognitive biases, can affect people’s ability to achieve and maintain SA