Presentation on theme: "Risk Reduction in Sedation and Analgesia"— Presentation transcript:
1Risk Reduction in Sedation and Analgesia Rowland P. Wu, MDAdapted from Glynne D. Stanley, MD
2Overview Complications occur because of: Inappropriate patient selectionUnanticipated responses from patient or equipmentOver-medicationWrong patient/wrong site/wrong procedure
3Strategies to reduce risk, ‘patient selection’ Improve patient selectionASA Classificationairway assessment and historyidentify other factors e.g. pregnancy, obesity
4Patient Selection Important ‘baseline’ assessments are: actual or estimated weightvital signs including baseline oxygen saturationcardiopulmonary statusgeneral neurological statusprevious adverse responses to medication (not just allergy detection)_ASA classification(Baseline airway evaluation)
5ASA Classification ASA 1 Normal, healthy patient ASA 2 Stable mild systemic diseaseASA 3 Severe systemic disease with functional impairmentASA 4 Severe disease, constant threat to life, not necessarily to be improved by surgeryASA 5 Moribund patient, not expected to survive without surgeryASA 6 Brain-dead donorEmergency (E)
6Patient SelectionAll patients should be carefully evaluated by the MD. Some ASA Class III, and most ASA Classes IV and V will not be suitable for sedation administered by non-anesthesiologists.
8Airway Assessment Mallampati classification Neck extension Thyromental distance (?short neck)Interincisor distance (?poor mouth opening)Concurrent obesity(History of airway problems)Letters and bracelets
9Patient SelectionAnesthesia consultation should also be considered under the following circumstances:patient has limited neck motion or cervical instabilitypatient has abnormal craniofacial anatomypatient is morbidly obesepatient has a history of sleep apneapregnant patientspatient has not been NPO
10Strategies to reduce risk, ‘unanticipated events’ Have available and be familiar with essential pieces of equipmentbasic interpretation of ECGunderstand pulse oximetry and know the limitations of usecapnographyreliable oxygen source, equipment for positive pressure ventilationknow how to quickly and reliably get help
21Unanticipated neurological events Possible causesovermedicationHypoxemiahypercarbiacerebral ischemiahypoxemiacerebral hypoperfusionundermedication?Neurological ‘Disconnection’drowsinessunresponsivenessuncooperativecombativedisinhibition
22Unexpected events: The catastrophe! Call for help/Code BlueDiscontinue sedative therapy, infusions /transfusions etcBegin BCLS/ACLS if appropriateprepare emergency equipment, drugstry to anticipate resuscitation needs
23Equipment problems: E.C.G. No trace/loss of tracePoor qualityIntermittent traceInterferencePossible causesASYSTOLE!!loose leadsincorrect placementdry electrodes!greasy skinrespiratory variationelectrical interference
24Equipment problems: Non-invasive BP no readingrepetitive cyclingvery low/high BP??Arterial linePossible causes:HYPOTENSION!HYPERTENSION!cuff leakwrong size cuffarrhythmia e.g. AFtubing kinkedpatient/MD movement
26Equipment problems: Pulse oximetry REMEMBER!Oximetry does not measure respirationthere may be a lag phase, depending on probe siteas with all the equipment:if it isn’t working at the beginning it will not suddenly get better, it is likely to let you down when you need it most.
27Strategies to reduce risk, ‘over-sedation’ Have an understanding of the pharmacology involved in conscious sedationTitrate drugs carefully to patient weight but especially to effect.Have appropriate reversal agents readily available and know how to use themKnow where other emergency drugs can be found
28Commonly Used Medications Midazolamintravenous/oral/intramuscular/intranasalInitial dose 0.5-2mg iv over 2 minOnset 1minute, peak 3-5 minsWait full 2 mins between doses with 0.5-1mg incrementsDuration 1-2 hours
29Commonly Used Medications ValiumInitial dose 2-5 mg ivOnset 1-5 minsWait full 5 mins between doses with 1 mg incrementsDuration 3-4 hours
30Commonly Used Medications FentanylOnset 1-3 min; peak-effect at 3-5 minutesInitial dose mcg ivtitrated in 25mcg doseslow dose drug is short actingDuration of effect mins
31Commonly Used Medications MorphineOnset 1-6 minInitial dose 2-5 mg ivtitrated in 2 mg doses but wait 3-5 mins between dosesDuration of effect 3-5 hours
32Commonly Used Medications MeperidineInitial dose mg ivOnset 2-8 mins, peak 20 minsMild vagolytic and antispasmodicNormeperidine is pro-convulsantDose titration mg; Duration 2-3hrsInteraction with MAOIs
33Overmedication Why does overmedication occur? Excessive dose Overly sensitive patient,concurrent medications or disease statesInadequate time for effect before more drug administeredAbnormal response such as hyperactivity leading to more medication
34Overmedication What problems does overmedication cause? Airway obstructionHypoxemia and hypercarbiaLoss of protective reflexesLoss of contact with the caregiverHemodynamic instabilityInterferes with the procedure
35Overmedication How may overmedication be managed? stop medicating! open airway and stimulate to breatheensure adequate oxygen supplycall for help early, especially if hemodynamic instabilityconsider reversal of medicationhave suction immediately available
36Overmedication How may medication be reversed? Opiates and benzodiazepines are the only drugs with specific antagonists:REMEMBER: once reversal agents are used this MUST lead to a longer period of post-procedure monitoring.
37Reversal Agents NALOXONE, 40mcg - 400mcg slow I.V. Onset 1-3 minutes, duration 45 minuteswill reverse analgesiamay cause pulmonary edemabeware withdrawal effects if long term narcotic usemay need repeating or infusion
38Reversal Agents FLUMAZENIL, 0.1mg - 0.2 mg I.V. for partial reversal 0.4mg - 1.0mg I.V. for complete reversalOnset 1-2 minutes, duration 45 minutesmay precipitate withdrawal seizurenot to be used routinelyhalf life of benzodiazepine may be long so flumazenil may need to be repeated
42Summary Choose your patients carefully. Check and understand your equipmentUse medication judiciously, you can’t take it out but you can always give more!Have reversal agents available but remember basic airway techniques.Be vigilant and prepare for the unexpected.