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PROCEDURAL SEDATION TRAINING PACKAGE, 2009

PRINCESS ALEXANDRA HOSPITAL EMERGENCY DEPARTMENT PROCEDURAL SEDATION TRAINING PACKAGE

Prepared by: Dr Tina Stathakis, Dr Glenn Ryan

10 December 2009

Adapted from The Sunshine Coast and Cooloola Health Services District, Queensland training

package, with permission.

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Table of Contents

GENERAL INTRODUCTION

LEARNING OBJECTIVES

DEFINITIONS

INTRODUCTION TO PROCEDURAL SEDATION

PRE-‐PROCEDURE PREPARATION

• Patient Assessment and Preparation

PREPARE FOR THE PROCEDURE

• Staff Requirements

• Location and Equipment

DURING THE PROCEDURE

SEDATION AND ANALGESIC AGENTS

POST PROCEDURE

DISCHARGE CRITERIA

SUMMARY -‐ SUITABILITY FOR PROCEDURAL SEDATION

ADVERSE EVENTS ASSOICATED WITH PROCEDURAL SEDATION

FLOW DIAGRAM FOR PROCEDURAL SEDATION

APPENDIX 1: Sedative and analgesic agents

APPENDIX 2: Management of Adverse Events

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GENERAL INTRODUCT ION:

The purpose of this training package is to standardize the approach to procedural sedation at PAH ED, and to ensure all staff performing procedural sedation are appropriately trained. This will

ensure safety and a high quality of care for patients. This package will also serve as a resource for

trainees undertaking the first or second part examinations.

The performance of procedural sedation to undertake painful diagnostic and therapeutic

procedures is now a core function of the modern emergency department. Consequently, the ability to safely perform procedural sedation is a fundamental skill for emergency physicians.

Required knowledge includes an understanding of indications for procedural sedation,

medications available and the most appropriate choice, patient factors including assessment and consent, staffing issues, appropriate environment to perform the procedure, monitoring,

documentation and discharge. The most important step in performing procedural sedation is patient selection.

CRITERIA FOR STAFF TRAINING

All staff must have appropriate airway and resuscitation skills before instigating procedural

sedation. Therefore it is recommended that all nursing and medical staff are current with Basic

and Advanced Cardiac Life Support.

THEORY COMPONENT INCLUDES 1. On-‐line power-‐point tutorial

2. On-‐line procedural sedation training package

PRACTICAL SKILLS COMPONENT INCLUDES

1. On-‐line simulated procedural sedation practical instruction video

2. Simulated procedural sedation case scenarios, with associated difficult airway and adverse event scenarios

This training package is aimed Emergency Medicine Trainees and nursing trainees who are

working in the Emergency Department at PAH ED.

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All procedural sedations are to take place in the resuscitation rooms. It is mandatory to inform the

duty consultant of all procedural sedation taking place in the department.

AUDIT

There will be a quarterly audit of the procedural sedation form, use of guideline and appropriate

documentation of procedures.

LEARNING OBJECT IVES Definitions

• Depth of Sedation

P r e P r o c e d u r e

• Patient risk assessment

• Assessment of contraindications

• Fasting status

• Consent

• Equipment and drug preparation

• Staff and skill level required

• Location

• Observation and monitoring

• Communication

During Procedure

• Drug administration

• Monitoring of Patient

• Recognition of adverse events / complications

Post Procedure

• Monitoring of patient

• Discharge criteria

• Discharge advice

Documentation

• Consent, procedure and monitoring

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Drug Information

• Propofol

• Ketamine

• Midazolam

• Fentanyl • Nitrous Oxide

Adverse Reactions / Complications

• Major and minor

INTRODUCT ION TO PROCEDURAL SEDAT ION: GOALS OF PROCEDURAL S EDAT ION :

1. Allow safe delivery of procedural sedation to ED patients: • Minimise anxiety, physical discomfort or pain and maximize patient care and satisfaction

for painful diagnostic and therapeutic procedures

• Control behavior and patient movement during the procedure

• Minimize psychological distress, minimize pain, maximize amnesia for the procedure

• Appropriate patient selection, identifying potential high risk patients that may be more

safely managed in theatre

• Prepare patient and their family

• Appropriate staff selection

• Prepare the appropriate environment, including equipment

• Appropriate medication selection

• Prepare for expected and unexpected outcomes

• Safe monitoring of patients

• Adequate documentation

2. Ensure optimal patient disposition

• Ensure safe discharge from the emergency department

• Provide written instructions for discharge and follow up as appropriate

3. Regular audit of procedures

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COMMON CONDITIONS SUITABLE FOR PROCEDURAL SEDATION IN ED • Dislocated joints with or without neurovascular injury

• Fractures and fracture dislocations with or without neurovascular injury

• Incision and drainage of abscesses

• Lumbar puncture

• Wound debridement

• Expedite investigations i.e. CT scan

DEFINITIONS:

Anxiolysis: • State of decreased apprehension about a situation without alteration of awareness

Amnesia: • Loss of memory for an event or period of time

Analgesia: • Relief of pain without intentional alteration of mental status. Alteration of mental state

may be a secondary effect of the medication used

Sedation: • A controlled reduction of environmental awareness and responsiveness to external stimuli

Procedural Sedation:

• A technique of administering a sedative or dissociative agent, usually with an analgesic, to promote a state that allows the patient to tolerate an unpleasant procedure while

maintaining spontaneous cardiorespiratory function, and hence airway control,

oxygenation and blood pressure

Minimal Sedation: • A drug-‐induced state during which patients respond normally to verbal commands;

cognitive function and co-‐ordination may be impaired, ventilatory and cardiovascular

functions are unaffected

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Moderate Sedation: • A drug-‐induced depression of consciousness during which patients respond purposefully to

verbal commands, either alone or with light tactile stimulation.

• Reflex withdrawal from pain does not constitute moderate sedation

• Airway reflexes, cardiovascular and respiratory function are maintained

Dissociation: • A trance-‐like cataleptic state, induced by an agent such as Ketamine, characterized by a

profound analgesia and amnesia. Protective airway reflexes, spontaneous respirations, and cardiopulmonary stability are retained

Deep Sedation: • A drug-‐induced depression of consciousness during which patients cannot easily be

aroused but will respond purposefully after repeated or painful stimulation. Protective

airway reflexes may be lost, along with spontaneous ventilation. Cardiovascular function is usually maintained

General Anaesthesia: • A drug-‐induced loss of consciousness during which patients are not arousable, even with

painful stimulation. The ability to independently maintain ventilatory function is often

impaired, as is ability to maintain patent airway. Positive-‐pressure ventilation and airway

control is often required. Cardiovascular function may be impaired.

The preferred depth of sedation is “moderate”, where the patient responds purposefully to voice

or light tactile stimulation. Depth of sedation is a continuum, without distinct separation between the stages. Transition between stages is difficult to predict, so it is easy to achieve sedation that is

too deep. Depth of sedation is not dependent on the medication used, but how the medication is

used, patient factors such as other ingestions, head injury, trauma and co-‐morbidities. Given the

difficulty predicting depth of sedation, sedation should be titrated and staff should be adequately trained to treat potential airway, respiratory and cardiovascular complications of sedation.

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PRE-‐ PROCEDURE PREPARATION:

1. PATIENT RISK ASSESSMENT:

Patient assessment is the most important step in determining suitability for procedural sedation in

the ED. There is an increased risk of adverse outcomes in patients who have the following:

• Extremes of age

• Difficult facial or neck anatomy, with increased risk of bag-‐valve-‐mask ventilation or intubation difficulty

• Patients with underlying significant disease states

• Previous anaesthetic difficulties

Patient assessment in determining suitability for procedural sedation includes the following:

History:

• Standard history as documented in emergency department medical record

• Health issues specific for patients undergoing procedural sedation, particularly risks for potential cardiovascular instability

• American Society of Anaesthesiologists (ASA) classification – assessment of the patient’s general physical status (see below)

• History of prior anesthetic or operations, and any potential problems encountered

• Current medications

• Smoking, alcohol and drug use. Alcohol use may result in patient’s having a “tolerance” to

certain medications, e.g. propofol

• Allergies

• Weight

ASA Classification

Class Description Examples Sedation Risk

I Normal and healthy No past medical history Minimal

II Mild systemic disease

without functional limitation

Mild asthma, controlled

diabetes

Low

III Severe systemic disease with

functional limitations

Pneumonia, poorly

controlled seizure disorder

Intermediate

IV Severe systemic disease that Advanced cardiac disease, High

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is a constant life threat renal failure, sepsis

V Moribund, may not survive

procedure

Septic shock, severe trauma Extremely high

Other risks to consider on history:

• Increased risk of airway compromise leading to obstruction o Snoring, stridor, sleep apnea

• Increased risk of hypoventilation o Reduced sensitivity to CO2 retention – chronic lung disease, neuromuscular

disorders

o Abnormalities of the respiratory centre – eg brainstem tumors

• Increased risk of aspiration o Vomiting, bowel obstruction, gastro-‐esophageal reflux o Altered mental state o Cerebral palsy

o History of aspiration

• Increased risk of bronchospasm or laryngospasm

o Asthma, recent respiratory tract infection

• Increased risk of cardiovascular compromise o Cardiac disease, hypovolaemia, sepsis

• History of sedation failure

• Drug specific conditions Examination:

• A directed physical assessment as documented in emergency department medical record, including patient vital signs, CVS and respiratory systems

• In addition, an anesthetic risk assessment, which includes airway risk assessment, specifically assessing for potential difficulty with bag-‐valve-‐mask ventilation or intubation.

This should be documented on the procedural sedation form

Airway Assessment

• All patients undergoing procedural sedation

• Patients with potentially difficulty airways must be discussed with the consultant prior to commencing

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• Assess for craniofacial abnormalities, facial fractures

• Beard

• Mouth -‐ Missing teeth, tongue size, Mallampati Classification (see below), mouth opening ( >2 fingers or 4 cms) , foreign body (including blood), difficulty protruding lower jaw

• Neck – range of movement, trauma, c-‐spine injury, distances (see below), length (short vs long)

• Pregnancy, obesity

• 3 tests when used together have almost 100% reliability in predicting airway difficulty 1. Mallampati classification

2. Thyromental distance

3. Extension at the atlanto-‐occipital joint

1. Mallampati classification

• With the mouth fully open, and tongue extended, the degree to which posterior oropharyngeal structures are visible reflects the associations between mouth opening,

tongue size, and oral pharynx size, which defines oral cavity access

• These relationships are loosely associated with intubation difficulty

• Ideal assessment occurs with patient sitting on the edge of the bed (or sitting up), mouth open as widely as possible, protruding tongue as far as possible without phonating (head in neutral position). Note this classification may vary if patient is assessed supine

• Class I view – correlates with grade 1 view at laryngoscopy and suggests intubation ease

• Class IV correlates with grade 3 or 4 view at laryngoscopy and suggests poor layngoscopic view and difficulty intubating

Class I – Soft palate, uvula, fauces, pillars visible

Class II – Soft palate, uvula, fauces visible

Class III – Soft palate, base of uvula visible

Class IV – hard palate only visible

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2. Thyromental distance (TMD):

• This is the distance from the mentum of the lower mandible to the thyroid arch

• Measured with the adult patient’s neck fully extended

• Helps establish how readily the laryngeal axis will fall in line with the pharyngeal axis

with atlantoaxial joint extension

• If TMD < 3 finger breadths (or <6 cm), difficult to achieve alignment, therefore less

space for tongue displacement during laryngoscopy, which increases the potential for

difficulty during intubation

3. Atlanto-‐occipital joint Extension

• Measured with head erect and facing forward

• Normal degree of atlanto-‐occipital joint extension = 35°

High Risk Patients Constitute: • Patients with severe systemic disease, with definite functional limitation, or that is a threat

to life (ASA > III)

• With or with potential for cardiovascular or respiratory instability

• With Mallampati Class III or IV airway , short TMD (< 6cm) and poor extension at atlanto-‐

occipital joint, difficulty protruding lower jaw, mouth opening < 4cm

• History of difficult intubation

2. ASSESS FASTING STATUS • ASA guidelines recommend a fasting time of 6 hours for solids and 2 hrs for clear liquids

• These guidelines are difficult to follow in the ED setting, and data to support their use in an

ED setting is lacking, with guidelines based on expert consensus extrapolated from patients

receiving a general anaesthetic with airway manipulation (intubation / extubation) – both things we are trying to avoid in ED procedural sedation. Studies in children do not show an

increased risk of aspiration dependent on fasting status

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• General consensus for procedural sedation fasting state in the ED setting: o solids 4 hrs

o Liquids 2 hrs

• Fasting status needs to be considered in light of the urgency for the procedure and risk-‐

benefit. For example, an unfasted patient with neurovascular injury due to a fracture-‐dislocation cannot wait 4 hours to be fasted prior to fracture reduction, compared with a

systemically well patient requiring incision and drainage. They may not be able to wait until

theatre to have their fracture reduced. Consequently a considered decision based on likely risk -‐ benefit of the procedure needs to be undertaken. If the procedure cannot be

performed safely in the ED due to an increased risk of aspiration, early discussion with the

Orthopaedic and Anaesthetics teams needs to be undertaken.

• Fasting status also needs to be considered in light of the sedative medication to be used. For example, ketamine tends not to cause loss of airway reflexes and so is considered to be

a safer sedative agent in unfasted patients

• In general: Step 1: Assess the patient risk

Step 2: Assess the nature and timing of oral intake Step 3: Assess the urgency of the procedure

Step 4: Determine the length & depth of sedation anticipated

• Assess nature and timing of oral intake within last 4 hours 1. Nothing

2. Clear liquids only

3. Light snack (includes breast and cows milk) 4. Heavier snack or meal

• Theoretically risk of aspiration increases from 1-‐4

• If not fasted, options include:

o Wait in ED until suitable time elapsed

o if not urgent, return at a later time fasted for procedure o if procedure cannot be deferred, refer for anaesthetic care and rapid sequence

induction in theatre

o consider alternative options for procedure, eg Biers block

High Risk Patients Constitute: • Unfasted for solids > 4 hours

• Severe injury (gastroparesis)

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• ALOC, head injured with increased risk of vomiting

3. OBTAIN INFORMED CONSENT • This includes a discussion about the risks, benefits, potential complications and side effects

of the procedure and the sedation

• Use Queensland Health generic consent form

PREPARE FOR THE PROCEDURE: 1. STAFF REQUIREMENTS:

• 2 doctors and one nurse o One doctor for the airway, adequately trained in airway management and

procedural sedation, able to manage the spectrum of potential complications.

Ideally, this person is not to get involved in the procedure itself

o One doctor for the procedure o One nurse to continuously monitor the patient and record vital signs from the start

of the procedure through to recovery. The nurse may get involved with minor,

interruptible tasks but is not to have any other responsibilities that would interfere in monitoring and documentation

• Staff roles clearly defined and communicated

2. DEPARTMENT SAFETY • The safety of the department will not be jeopardised by the performance of the procedure

• There must be available staff, an available resuscitation room and the department must be

able to cope with the loss of those staff and the room for the duration of the procedure

3. LOCATION AND EQUIPMENT • Resuscitation room with access to full non-‐invasive monitoring as well as appropriate

equipment and medications to manage airway complications, allergic reactions,

cardiovascular and or respiratory arrest and drug overdose

• Resuscitation equipment checked and available by patient’s bedside

• Airway equipment checked and laid out ready to use, including oxygen, bag-‐valve-‐mask,

guidels and nasopharyngeal airway, appropriately sized ETT and stylet, appropriately sized LMA, laryngoscope, suction, bouge and difficult airway equipment as indicated

• Appropriate splints/ casts prepared and available at patients bedside

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• Monitoring equipment attached to the patient

• Intravenous cannula in situ and normal saline via giving set attached

• Appropriate sedation and analgesic agents drawn up and available

• Appropriate resuscitation drugs and antidotes available

4. OBSERVATIONS AND MONITORING: • a comprehensive, relevant set of observations must be obtained immediately prior to the

administration of sedation and should be documented on the observation chart

• Observations include:

o Pulse

o Pulse oximetry o ECG trace

o Blood pressure

o Respiratory rate o Conscious state (or sedation score) o Pain score

o Circulation observations o Capnography

• Pulse oximetry, pulse rate, ECG trace, respiratory rate and capnography should be

monitored continuously and recorded 2 minutely during the procedure

• Blood pressure should be recorded 2 minutely during the procedure. Sedation score and pain score may be recorded 5 minutely throughout the procedure

• Subsequent observations post-‐procedure should be performed and recorded at least 5 minutely immediately after procedure as the patient re-‐gains consciousness and 15 to 30 minutely until the patient is ready for discharge, dependent on the patient’s rate of

recovery to pre-‐sedation conscious state

• The treating doctor must be informed of any variances in vital signs and observations to

ensure appropriate interventions

5. MEDICATION ORDERS • All mediations used in sedation, including nitrous oxide, require documentation in the

patient’s medication sheet. Please include date and time given

• Please note medications given pre-‐procedure (including pre hospital setting) as these may affect the procedural sedation

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6. DOCUMENTATION: The following documents are required when performing procedural sedation:

• Patients emergency department medical records

• Procedural sedation form

• Consent form

• Medication sheet

• Fluid order sheet

• Observation sheet

• Patient discharge sheet/discharge advice

DURING THE PROCEDURE:

1. OBSERVATIONS AND DOCUMENTATION • As outlined above

2. DRUG ADMINISTRATION: • Drug selection is tailored to the procedure, the requirement for sedation and analgesia,

patient factors including age, previous sedation and response, allergies and route of administration

• Drug selection requires knowledge of dosage, pharmacodynamics and pharmacokinetics of

sedative and analgesic agents (see appendix)

• Agents such as propofol and midazolam have no analgesic properties and require co-‐administration of an analgesic such as Fentanyl. Use of an agent such as Fentanyl will likely

reduce the dose of sedative agent required

• The sedative drug chosen is administered in incremental doses and titrated to effect to

provide a specific level of sedation that achieves the goals of sedation for the procedure

• It is important to recognise that unintentional deep sedation or general anaesthesia can

occur unpredictably in individual patients with the use of most agents and combinations

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Commonly Used Drugs: Drug Guide Dose Peak Duration Cautions and Notes

Propofol 0.5-‐1mg/kg 1 min 10 mins Prolonged apnoea may

occur – especially with

fentanyl

Ketamine IM 2-‐4mg/kg

IV 0.5 – 1mg/kg

(slow)

<5 mins 5-‐20 mins Rapid IV→

apnoea/hyperventilation.

Beware of emergence

phenomena &

hypersalivation; consider

adjunctive agents

Morphine IV 0.1 – 0.2 mg/kg 5 – 30mins 3-‐4 hrs If given with midazolam,

give morphine first and

await peak effect

Fentanyl IV 0.5 – 2 mcg/kg 2-‐5 mins 30-‐60 mins Prolonged apnoeas may

occur, especially with

propofol

Midazolam IV 0.1 mg/kg 1-‐5 mins hours Elderly initial bolus of

0.5mg, fit adults 1mg

Nitrous & O2 O2: nitrous max

30:70; start at

50:50, as nitrous

needed

2 mins Minutes

Monitoring the patient’s sedation and adverse events

• The AVPU sedation score is a rapid assessment tool of conscious level

• A = Alert V= responds to Voice P= responds to Pain U= Unresponsive

Additionally all sedation (excluding Ketamine) should be graded using a simple scoring system

(Wisonson Sedation Score) which captures both the depth and quality of sedation (Hoffman

2002) 11.

Inadequate 6 Anxious, agitated. IN PAIN!

Minimal

conscious

5 Awake without stimulus

Moderate conscious

4 Drowsy but easily roused with verbal stimuli

Moderate-‐ deep

3 Requires moderate tactile or loud verbal stimuli to rouse

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Deep 2 Rouses slowly to consciousness with painful stimuli

1 Rouses but not to consciousness with painful stimuli

Unconscious 0 Unresponsive to painful stimuli

POST PROCEDURE: • The patient must be observed by a member of nursing staff in the resuscitation bay until

full recovery to pre sedation state has been reached.

• All side effects or adverse events should be documented in the patient’s records in addi-‐

tion to noting on the Procedural Sedation Record.

• Keep the patient nil by mouth until fully alert

DISCHARGE CRITERIA The patient cannot be discharged until discharge criteria are met. It is impossible to set a specific “discharge time” post administration of sedation. Each patient responds to sedation on an individ-‐

ual basis. It is essential to assess each patient individually using the following discharge criteria:

• Resumption of pre-‐sedation level of consciousness • Resumption of purposeful neuromuscular activity • Ability to ambulate – age appropriate • Ability to verbalize – age appropriate • Vital signs returned to and maintained at pre procedure status • Ability to tolerate oral fluids • Pain score less than 4 • Minimal nausea, vomiting resolved if present

For an intellectually disabled adult, the aim is to achieve the pre-‐ sedation level of consciousness or as close as possible to the normal level of functioning for the particular patient. This can be

achieved by communicating with the parent / guardian/ carer to establish what is ‘normal’ for the

patient. A responsible adult needs to be available to accompany the patient home.

The discharge advice brochure should be given to the patient and documented accordingly.

Patients should be advised not to drive or participate in complex activities for 24 hours.

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SUMMARY -‐ WHO IS SUITABLE FOR PROCEDURAL SEDATION: • Healthy and fasted patients

• ASA of I or II is usually safe for procedural sedation in the ED. ASA of III or more must be discussed with ED consultant prior to planning the procedure

• No potential airway difficulties identified on examination

• Suitable common conditions include dislocated joints, fractures and fracture dislocations requiring reduction, incision and drainage of abscesses

WHO IS NOT SUITABLE FOR PROCEDURAL SEDATION? • More severely ill patients – ASA IV, V unless limb threatening injuries

• Extremely painful or prolonged procedures

• Anesthetic risk as identified on history and examination, particularly airway examination

• Patients extremely anxious who would be more suitable for general anesthetic

PROCEDURAL SEDATION SHOULD NOT BE PROVIDED IN THE ED • When there is no Emergency Consultant aware of the procedure taking place

• When the required number of appropriately skilled staff are not available

• When the appropriate staff cannot be dedicated to their roles due to other demands in the ED

• When appropriate clinical area with full resuscitation equipment cannot be dedicated for the procedure to take place

• If the procedure will place undue demands on the department, jeopardizing departmental safety

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SUMMARY OF GUIDELINE FOR PROCEDURAL SEDATION

Patient select-

ed and risk of

sedation as-

sessed

Patient in re-

sus & ED con-

sultant notified

Staff as-

sembled 2

medical, 1

nursing

pared

Sedation and

vitals monitored

Consent ob-

tained

Equipment and

drugs pre-

Safe discharge

criteria

Discharge advice

Documentation

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ADVERSE EVENTS

The incidence of documented adverse events related to procedural sedation varies in reported studies. However, ensuring that PS is carried out by accredited staff knowledgeable in the preven-‐

tion, identification and management of adverse events reduces the potential for negative out-‐

comes. Adverse events are also dependent on the medication used for the procedure, for exam-‐ple emergence phenomena with ketamine.

Adverse events must be documented in the patient’s records and should a major incident occur, a PRIME report generated.

Major adverse events encompass:

• Laryngospasm / bronchospasm • Hypoxia – sustained (O2 sats <92) • Apnea – requiring bag/mask ventilation or intubation • Airway repositioning – depression of protective airway reflexes requiring airway adjunct or

sustained jaw lift maneuver • Pulmonary aspiration • Hypotension – sustained • Severe emergence agitation requiring intervention • Seizures • Allergic reaction

Minor adverse events encompass:

• Transient rash • Nausea & vomiting • Dizziness • Hypertonicity • Hypersalivation • Pain at the infusion site -‐ propofol

Other complications include:

• Failure to achieve adequate sedation • Unintentional deep sedation • Prolonged or excessive sedation • Malignant hyperthermia

Complications of the procedure

• Failure • Neuropraxia, vascular injury

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APPENDIX 1 – SEDATIVE AND ANALGESIC AGENTS BENZODIAZEPINES (Midazolam) Background

• Short acting, CNS depressant that is sedative and hypnotic

• No analgesic effects Example

• Most commonly used agent -‐ Midazolam Route

• IV, IM

Pharmacodynamics

• Benzodiazepines act at the gamma amino butyric acid A receptor (GABAA), a chloride chan-‐

nel. The do not substitute for GABA, or open the channels directly, but appear to potenti-‐

ate the effects of GABA through increasing the frequency of chloride channel opening events. The effect is to cause hyperpolarisation of the post-‐synaptic membrane, leading to

decreased firing of critical neurons. The end result is inhibition.

• GABAA receptors are located at all levels of the CNS

• Effects are dose dependent and also dependent on other medications used

Pharmacokinetics

• Absorption and bioavailability o IV – 100%, onset of action 2-‐3 minutes, duration is dose dependent, approximately 2

hours

o IM – > 90% bioavailability, onset over 15 minutes, peak plasma levels in 45 minutes

• Metabolism – hepatic (Cytochrome P450 3A4 (CYP 3A)), conjugation to active metabolite 1-‐

hydroxymethyl midazolam which is undergoes further conjugation. There may be interac-‐

tions with other drugs that rely on P450

• Excretion – less than 0.03% excreted in urine as intact midazolam

• Elimination ½ life is 1.4-‐2.4 hours

• Elimination ½ life is prolonged in critically ill, patients with congestive cardiac failure and

obese patients. Pharmacokinetics are unchanged in chronic renal failure Indications

• Management of procedural anxiety, amnesia during procedures, control of seizures, ongo-‐

ing sedation in intubated patients

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Contraindications for Use

• Patients with cardiovascular instability -‐due to the potential for hypotension or bradycar-‐

dia.

• Patients with previous adverse events to midazolam sedation

• Myasthenia gravis.

• Acute glaucoma

Precautions

• Elderly

• Hepatic failure

• Rapid IV administration increases the risk of respiratory depression.

• Co-‐administration of systemic opioids can cause a worsening of respiratory depression.

Interactions

• CNS depressants – alcohol, opioids, antihistamines, anti-‐psychotics – increase sedation,

respiratory depression and CVS effects

• Medications that effect CYP 3A (e.g. phenytoin, carbamazepine, macrolide antibiotics)

Reversal

• Effects reversed by Flumazenil, a benzodiazepine antagonist. Dose in adult 300-‐600mcg Adverse reactions

• Cardiorespiratory depression (hypotension, bradycardia and respiratory depression)

• Paradoxical excitement (10-‐15%)

• Prolonged sedation

• Emergence delirium

Side effects are dose related and vary with route of administration. The highest risk

of major side effects is IV administration

Dose

• 0.1mg/kg with onset 2-‐3 minutes, and titrated to effect

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KETAMINE Background

• Ketamine is an analgesic and a dissociative anesthetic agent, characterised by catatonia,

amnesia and hypnosis. It is related in structure to phencyclidine (PCP) Route

• IV, IM Pharmacodynamics

• Ketamine exerts its effect by ‘‘disconnecting’’ the thalamoneocortical and limbic systems

effectively dissociating the central nervous system from outside stimuli (e.g., pain, sight,

sound). The resulting trancelike ‘‘sensory isolation’’ is characterized by potent analgesia,

sedation, and amnesia while cardiovascular stability is maintained and spontaneous respi-‐rations and protective airway reflexes are preserved. Heart rate, blood pressure and cardi-‐

ac output transiently rise with peak rise at 2-‐4 minutes, before returning to pre-‐sedation levels within 15 minutes of injection. Ketamine produces its CVS stimulation by excitation

of the central sympathetic nervous system and noradrenalin re-‐uptake inhibition at sympa-‐

thetic nerve terminals. Increase in plasma adrenaline and noradrenalin occurs as early as 2 minutes and return to control levels over 15 minutes

• May cause a transient decrease in respiratory rate for 2-‐3 minutes

• Diplopia and nystagmus, myoclonic jerks are normal

• The complete analgesia typical of the dissociative state permits extremely painful proce-‐dures to be performed that would otherwise be difficult using traditional moderate or

deep sedation with benzodiazepines and opioids

• Increases cerebral blood flow, oxygen consumption and may increase intracranial pressure

• It has many features that are attractive in the emergency setting: rapid onset (less than 5 minutes IM or IV), consistently effective analgesia and amnesia, airway stability and ac-‐

ceptable recovery duration to discharge (70 –140 mins depending on route of administra-‐

tion) Pharmacokinetics

• Highly lipid soluable. Up to 93% bioavailability after IM injection

• Rapidly distributed to highly vascular tissue including CNS

• Plasma ½ life of 2-‐4 hours

• Metabolism – hepatic – dealkylation, hydroxylation and conjugation

• Excretion – 2-‐5% excreted unchanged in urine, 5% in feces, metabolites renally excreted

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Indications for use

• Ketamine is an ideal agent to facilitate short painful procedures which might otherwise re-‐

quire general anesthesia:

• Very painful procedures, including laceration repair -‐ complex or cosmetic laceration re-‐

pair; wound exploration – foreign body; reduction and immobilization of fracture and / or dislocation; incision and drainage procedures

• Need for immobilization

• Removal of foreign bodies from eye, ear, nose and skin

• Note – non-‐dissociative doses can be used for analgesia only Contraindications for use in adults

• Anaphylaxis or previous adverse reaction to ketamine

• Psychosis

• Procedures involving laryngeal stimulation – ketamine potentiates the gag reflex

• Airway instability, stenosis, trachea surgery

• Upper respiratory infections, active asthma (increased risk of laryngospasm)

• Cardiovascular disease – poorly controlled hypertension, recent AMI, stroke

• Head injury with associated loss of consciousness, hydrocephalus, CNS lesions

• Acute glaucoma

• Thyroid disease and porphyria

Common Side Effects

• Diplopia, Nystagmus, Myoclonus

• Hypersalivation

• Post-‐procedure nausea

Adverse Reactions

• Laryngospasm

• Airway malposition

• Respiratory depression

• Excessive hypersalivation

• Cardiovascular stimulation, arrhythmias

• Musculoskeletal effects and Ataxia

• Intracranial pressure elevation

Recovery reactions

• Emergence Reactions o Ketamine can stimulate hallucinatory reactions during recovery, which may be ei-‐

ther pleasant or unpleasant. When Ketamine is administered in adults, clinicians

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should be aware of the rare potential for pronounced reactions, including night-‐

mares, delirium, excitation, and physical combativeness. Titrated benzodiazepines

appear to consistently and rapidly pacify such reaction.

• Vomiting The following table illustrates the differences between administration of ketamine IV and IM.

There is no reversal agent for ketamine.

Dosage and administration

Route of Administration Intramuscular (IM) Intravenous (IV)

Advantages No IV necessary Ease of repeat dosing, faster recovery

Clinical onset 5 minutes 1-‐2 minutes

Duration of effective dis-‐

sociative sedation

20-‐25 minutes 5-‐10 minutes

Recovery time 100 – 140 minutes 70 – 100 minutes

Initial dose 4mg/kg 0.5-‐1mg/kg

Subsequent dose Insert IV and give

further doses 0.25 – 0.50 mg/kg IV

0.25 – 0.50 mg/kg

Maximum dose 5mg/kg 5mg/kg

Warning IV administration must always be given over a period of greater than 60 seconds.

Rapid IV administration is associated with transient respiratory depression including apnea

Drug preparation

IV administration

• Ampoules 200mg in 2 ml.

• Dilute with 18 mls of H2O or NaCl to achieve concentration of 10 mgs/ml.

25

PROPOFOL Background

• Propofol (Diprivan injectable emulsion) is an intravenous ultra short acting seda-‐

tive/hypnotic agent used for the induction and maintenance of sedation and anesthesia.

• A therapeutic dose of Propofol produces hypnosis with minimal excitation in approximate-‐

ly forty seconds from the start of the injection, with rapid recovery. It does not appear to

cause cumulative effects or delayed arousal after prolonged infusion

• Adverse reactions can be reduced by slower induction titrating to the lowest dose produc-‐

ing optimal sedation. Transient cardio-‐respiratory depression can be safely managed in

clinical practice.

• It has no analgesic action thus mandating co-‐administration of opioid analgesics for painful

procedures. Propofol contains glycerol, soya oil, egg, lecithin and sodium hydroxide.

• Post-‐sedation vomiting is uncommon as propofol is thought to have anti-‐emetic properties Route

• IV only

Pharmacodynamics

• Mechanism of action is poorly understood

• Dose dependent cardiovascular depression – decreased peripheral vascular resistance and myocardial depression / negative inotropy

• Respiratory depression can lead to apnoea Pharmacokinetics

• Three compartment model – plasma, rapidly equilibrating tissue and slowly equilibrating tissue. After injection

• Following an IV bolus dose, rapid equilibration occurs between the plasma and the highly

perfused tissue of the brain, accounting for the rapid onset of anaesthesia. Plasma levels initially decline rapidly as a result of both distribution and metabolic clearance. The initial

(distribution) half-‐life is between 2-‐8 minutes, followed by a rapid elimination phase with a

half-‐life of 30 to 60 minutes and followed by a slower final phase, representative of redis-‐tribution of propofol from poorly perfused tissue.

• Metabolism – hepatic through glucuronide conjugation

• Less than 1% excreted unchanged

• Total body clearance is greater than hepatic blood flow, suggesting that it’s elimination in-‐cludes extra-‐hepatic mechanisms in addition to hepatic metabolism

Indications for use Short term for moderate and deep procedural sedation

26

• Removal of foreign bodies

• Cardioversion

• Fracture reduction

• Relocation of joint e.g. shoulder or hip

• Short laceration repair

Contraindications for use

• Epileptic patients have increased risk of seizure in the recovery phase.

• Anaphylaxis is rare but should not be used in patients with egg, lecithin, glycerol, and soya

oil allergies.

• pregnancy (no direct harm to fetus but increased rate of maternal death) Adverse Reactions

A prospective study of 392 patients aged 1-‐18 years found minimal significant adverse reactions

using recommended doses 26

• Cardiovascular depression – asystole, bradycardia, tachycardia, hypotension

• Respiratory depression/Apnea/Airway obstruction

• Localized pain – thrombosis/phlebitis

• Excitation phenomenon – twitching, tremor, hypertonia, involuntary movements, hic-‐coughs

• Allergy/anaphylaxis

• Flushing /rash Interactions

• CNS depressants, opioids – increases sedation, increased risk of cardiovascular and respira-‐

tory depression

Dose

Adults Induction for deep sedation

• 0.5-‐1.0 mg/kg bolus (titrate slowly over several minutes) and 0.5 mg/kg subsequent bolus-‐

es

Sedation in ventilated patients

• Induction dose then 1-‐3 mg/kg/hr by IV infusion

27

OPIOIDS

MORPHINE Introduction

• Opioid analgesics are excellent agents for procedural sedation especially as adjuncts for pa-‐tients who have significant pain before, during and after a procedure eg relocation of a dis-‐

located shoulder.

• They are often used as adjuncts to manage pain pre-‐procedure, and given their CNS ef-‐

fects, allow for reduced amounts of sedative agents

• Analgesics are often given in the pre-‐hospital environment prior to presentation to the ED

and the seditionist needs to consider this when giving other subsequent sedating medica-‐tions.

• Morphine and fentanyl can be used in combination with N2O, benzodiazepines and Propofol. Multimodal use of procedural sedation and analgesic (PSA) agents allows crea-‐

tion of a better sedation experience while reducing the dose of each agent. Common agents

• Morphine 0.05 -‐ 0.10 mg/kg IV

• Fentanyl 1-‐2 mcg/kg IV

• Codeine

• Endone Co-‐administration with other agents

• Opioid + N2O

• Opioid + N2O + benzodiazepine

• Opioid + benzodiazepine

• Opioid + Propofol

MORPHINE • A naturally occurring alkaloid, the active substance in opium

Route

• IV, IM, Subcutaneous

Pharmacodynamics

• Bind to specific receptors located in the brain and spinal cord regions – mu, delta and kap-‐

pa – and act to modulate pain transmission at these sites. Receptors are lined to G pro-‐teins. They act to modulate pain transmission through closing voltage gated calcium chan-‐

28

nels on presynaptic nerve terminals, reducing calcium influx and hence neurotransmitter

release, or they hyperpolarize post-‐synaptic neurons and inhibit their firing through open-‐

ing potassium channels

• mu – principal receptor responsible for euphoria, analgesia, respiratory depressant, physi-‐cal dependence. Kappa and delta may also contribute to analgesia

• Major organ effects:

o CNS – analgesia, euphoria, sedation with little or no amnesia, respiratory depres-‐

sion, dysphasia, cough, miosis, truncal rigidity, nausea and vomiting o CVS – hypotension can occur from central effects and histamine release

o GIT – constipation , increased resting tone especially small intestine, with spasms

o Biliary tract – sphincter of Oddi constriction

o Genitourinary – urinary retention o Neuroendocrine – ADH release

Pharmacokinetics

• Absorption – well absorbed from subcutaneous and intramuscular sites as well as from

mucosal surfaces of the nose or mouth. Rapid absorption from the GI tract, but subjected to first pass metabolism in the liver. Codeine and oxycodone are protected from conjuga-‐

tion and thus have a high oral:parenteral potency ratio.

• Distribution – rapidly leave the blood stream and concentrate in highly perfused tissues such as the brain, lungs, liver, kidneys and spleen. Drug concentrations in skeletal muscle

are lower, but this acts as a drug reservoir due to greater mass. May accumulate in fatty tissue

• Metabolism – hepatic metabolism to active metabolites. Morphine is conjugated with glu-‐curonic acid to form morphine-‐6-‐glucurinide which is more potent than morphine; Accu-‐

mulation occurs in renal failure with prolonged sedation; codeine, oxycodone are metabo-‐

lized by CYP2D6; Excretion – renal, minimal excreted unchanged. Small amounts of metab-‐olites excreted in bile

Precautions

• Using combinations of opioid and other agents have accumulative effects on the depth of

sedation and care must be taken to avoid adverse side effects

• Reduced doses are needed with the elderly, debilitated & patients with renal, hepatic, car-‐diac or respiratory dysfunction

• Endocrine disease – adrenal insufficient, hypothyroidism

• Atopic patients may have increase histamine release

• Tolerance – larger doses are required, or an alternative analgesic agent

29

Indications

• Analgesia, adjunct in procedural sedation

Contra-‐indications

• MAOI’s (within 14 days)

• Myasthenia gravis

• Opioid hypersensitivity

Interactions

• CNS depressants, sedatives and hypnotics

• MAOIs – serotonin syndrome

Adverse effects


• Hypotension

• Histamine release

• Local rash

• Urticaria/wheeze

• Nausea/vomiting

• Constipation

• Urinary retention

• SIADH Reversal Agent

• Naloxone is a pure antagonist. This agent should not be needed if appropriate dose regi-‐

mens are used. Abrupt reversal can cause sudden emergence with severe pain and massive catecholamine output which can precipitate ischaemic chest pain, arrhythmias and acute

heart failure in the elderly.

FENTANYL • A synthetic opioid , related in structure to phenylpiperidine

Pharmacodynamics

• Mu receptor agonist, 80% more potent than morphine. Decreased respiratory depression

effect, shorter duration of action than morphine

• Increased dose can cause muscle rigidity

Pharmacokinetics

• Absorption – IM, IV, Mucosal, transdermal

• Metabolism – hepatic -‐ undergoes hepatic oxidation (P450 enzyme CYP3A4 N-‐dealkylation)

30

• Excretion – renal Indications

• Analgesic of short duration, pre-‐medication for procedural sedation,

• Relocation of dislocated shoulders, hips, ankle, elbow (Opioid & Propofol)

Contraindications

• MAOI’s (within 14 days)

• Myasthenia gravis

• Opioid hypersensitivity Precautions

• Impairment of pulmonary function

• Cardiovascular instability

Adverse Reactions


• Hypotension

• Histamine release

• Local rash

• Urticaria/wheeze

• Nausea/vomiting

• Muscle rigidity (High dose fentanyl in infants) Reversal Agent

• Naloxone is a pure antagonist. This agent should not be needed if appropriate dose regi-‐

mens are used. Abrupt reversal can cause sudden emergence with severe pain and massive catecholamine output which can precipitate ischaemic chest pain, arrhythmias and acute

heart failure in the elderly.

Dosage ADULTS:

• Aliquots of 25-‐50mcg given IV every 2-‐3 minutes until rousable with an adequate respira-‐tion rate

31

NITROUS OXIDE

Background

• Laughing gas

• Inhalational anaesthetic / nalagesic agent

Route

• Inhalation via mask / mouth piece Pharmacodynamics

• Analgesic agent

• Low potency anaesthetic secondary to MAC > 100%

• CNS – sedative effects, euphoria

• CVS – myocardial depression, increased peripheral resistance Pharmoacokinetics

• Absorption -‐ rapid uptake to highly perfused tissue (i.e. brain) as low blood:gas coefficient which means it is poorly soluable in blood. Low soulability means it reaches high arterial tension and thus diffuses into areas of lower concentration i.e. brain

• Metabolism – not metabolised. Rapidly diffuses out of tissues back itno blood stream and exhaled via lungs

• Excretion – washout via lungs – rapid elimination

Indications

• Procedural sedation

• Labour, adjunct in general anaesthetics) Contraindications

• Trapped gas – pneumothorax, pneumocephaly, small bowel obstruction

• Facial trauma / oral trauma

• Patient unable to hold mask / breathing apparatus to face

Special Precautions

• Diffusion hypoxia – large quantities of N2O diffusing back from the blood onto alveoli at

the end of the procedure can result in hypoxia. Apply high flow oxygen during recovery phase to wash out N2O

Dose

• Nitrous-‐xide and oxygen mix

• Patient directed – patient holds mask to face

• Start inhalation 2 minutes prior to procedure to allow for effect

32

APPENDIX 2: -‐MANAGEMENT OF ADVERSE EVENTS

Airway obstruction

• Call for help

• Chin lift, jaw thrust

• Clear airway eg suction

• Adjuncts: Guedel, nasopharyngeal airway

• Supplemental O2 (FIO2 -‐1.0)

• Adrenaline if allergic obstruction

• Advanced airway management: Laryngeal mask (LMA) Endotracheal tube (ETT)

• Surgical airway management

Hypersalivation • Suction

• Positional manoeuvre eg Lateral position /head down

• Atropine

Laryngospasm • Call for help

• Clear airway/suction oropharyngeal secretions

• Supplemental O2 (FIO2 -‐1.0)

• Larson maneuver

• Bag/valve / mask (BVM) with reservoir. Give PEEP

• Prepare for Rapid sequence induction

• Give Suxamethonium if significant hypoxia

• ? Lignocaine 1-‐1.5 mg/kg

Hypoventilation/apnea • Call for help

• Ensure adequate and clear airway

• Supplemental O2 100%

• Assist ventilation with BVM

• If prolonged, chemically reverse sedatives

• Advanced airway and ventilation measures

33

Aspiration of stomach contents • Head down/ lateral position

• Suction and clear airway


• Assist ventilation after airway toilet

• May need BIPAP/IPPV and PEEP

• May need rigid bronchoscopy and removal of particulate matter

• Bronchodilators

• Antibiotics

Desaturation (SaO2 < 92%) • Ensure adequate and clear airway


• Assist ventilation

• Ensure adequate circulation

• Reverse sedatives if necessary

Adverse events (Circulation) • Bradycardia Treat cause Atropine

• Asystole Treat cause Adrenaline, atropine

• Tachycardia Treat cause ILCOR regimen

• VT/VF Treat cause ILCOR regimen

• Hypotension Fluid challenge Treat cause

• Hypertension Treat cause

Allergy and anaphylaxis • Rash -‐ “Watch & see” IV promethazine if needed

• Wheeze -‐ Salbutamol and hydrocortisone

• Hypotension -‐ Adrenaline, adrenaline, adrenaline hydrocortisone H1 and H2 , Blockers, IV

fluids (colloids)

• Intensive supportive care

Pain, distress and agitation • Ensure adequate ABC

• Psychological support

• Distraction

• Analgesia

• Increase PSA

34

• Opioid premedication

• Treat cause

• Firm “gentle” physical restraint

Paradoxical reaction • Not uncommon with midazolam

• Occasional with N2O

• Opioid premed often prevents

• Ensure adequate analgesia

• Firm “gentle” restraint

• Reverse with Flumazenil IN or IV

Emergence reaction • Low noise, dimmed lights

• Ensure adequate analgesia

• Often responds to opioids

• Midazolam sometimes helps

• Firm “gentle” restraint

Vomiting • Lateral position/ suction

• First line -‐ metoclopramide 0.2-‐0.5 mg/kg

• Second line -‐ ondansetron 0.1 mg/kg

• Third line -‐ dexamethasone 0.15 mg/kg

• Use all 3 for severe nausea and vomiting

• Droperidol 10mcg/kg

• Promethazine 0.5 mg/kg

• Midazolam for extreme agitation

• Paracetamol for pain

Drug induced muscle rigidity • Tramadol, fentanyl, morphine treat with naloxone

• Dystonia, akathisia treat with benztropine 0.01-‐0.02 mg/kg

• Neuroleptic malignant syndrome (NMS) and malignant hyperthermia (MH) treat with dan-‐trolene, bromocriptine

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