NON OPERATING ROOM ANAESTHESIA

transcript

ANAESTHESIA OUTSIDE OPERATING ROOM

DR UNNIKRISHNAN P, ASST. PROFESSOR

TRAVANCORE MEDICAL COLLEGE,KOLLAM, KERALA,INDIA

• Physicians are doing many things, which were surgeons areas previously.

• E. g. Interventional radiologists, gastroenterologists, or interventional cardiologists

• And this means, we are getting additional..

RESPONSIBILITIES

Away from familiar territories…• The indifferent reflexes

shown by the non operating room staff in emergency situation

• Insecurity due to a very realistic anticipation of lack of equipment and staff support

• Despite these factors, we should be held responsible if something happens…!

What is there in a name….?

• Nonoperating room anesthesia (NORA)

• Anesthesia at remote location• Outpatient anesthesia • Office-based anesthesia (OBA)

A very busy innings expected….

• Number of NORA activities has increased rapidly ( CT, MRI, neuroradiologic procedure or electroconvulsive therapy)

• And the procedures have become more complex

Special problems of NORA

• Limited working place, limited access to the patient,

• Electrical interference with monitors and phones, lighting and temperature inadequacy,

• Use outdated , old equipment• Staff less familiar with the management of

patients• Lack of skilled personnel, drugs and supplies• there is often no regular check up of the

anaesthesia inventory

Patient desaturating..I need a mask quickly…

Sure sir…here it is…

Hello..hello ...Who are you..?

• A trained anaesthesiologist should provide anaesthesia in remote locations within the hospital.

• However non anaesthesiologists are allowed to provide ‘conscious sedation'.

• It is mandatory that all providers should be Adult Cardiac Life Support (ACLS) certified.

Tour destinations!

• Radiology suites e.g. cardiac angiography, interventional radiology, CTscan, MRI

• Endoscopy suites• The dental clinic• The burns unit• Psychiatric unit for electroconvulsive

therapy• Renal unit for lithotripsy • The gynaecology unit for in vitro

fertilisation.

OUR AIMS

• Guard the patient's safety and welfare

• Minimise physical discomfort and pain

• Control anxiety, minimise psychological trauma and maximize the potential for amnesia

• Control movement to allow safe completion of the procedure

• Return the patient to a state in which safe discharge from medical supervision is possible.

CHALLENGESEQUIPMENT

Don't expect Volks Wagens! But ensure the Ambassador is not leaking petrol !

• The design of the anaesthesia machine may not be familiar

• do routine safety checks, such as ensuring that the oxygen failure alarm is working

• Make sure that we can see the anaesthetic machine during the case – e.g. radiology procedures are invariably undertaken in darkened rooms

DEXMEDITOMIDINE

Equipment check list for anaesthesia or sedation in a remote location away from the operating theatreRemember the acronym S O A P M ES (suction) – Appropriate size suction catheters & functioning suction apparatus.O (oxygen) – Reliable oxygen sources with a functioning flow meter. At least one spare E-type oxygen cylinder.A (airway) – Size appropriate airway equipment:• Face mask• Nasopharyngeal and oropharyngeal airways• Laryngoscope blades• ETT• Stylets• Bag-valve-mask or equivalent device.P (pharmacy) – Basic drugs needed for life support during emergency:• Epinephrine (adrenaline)• Atropine• Glucose• Naloxone• FlumazenilM (monitors):• Pulse oximeter• NIBP• End-tidal CO2 (capnography)• Temperature• ECGE (equipment):• Defibrillator with paddles• Gas scavenging• Safe electrical outlets (earthed)• Adequate lighting (torch with battery backup)• Means of reliable communication to main theatre site.

Sisterrrrrrrrrr......…. I meant LARYNGOscope , not this… ENDOscope…,please get me one…..• emergency trolley with a defibrillator

should be immediately available.• always check O2 source, cylinder keys,

illumination of laryngoscopes,working suction, emergency and resuscitation drugs enough number of extension lines (high pressure and low pressure), operating table functionality soon after you enter the room….

• back-up of at least one full E type oxygen cylinder is advisable;

Monitors

• Pulse Oximeter, NIBP, ECG and ETCO2 are a minimum requirement.

• In a non-intubated patient, ETCO2 monitoring can be achieved by taping the sampling line to the patient’s upperlip

• The expired CO2 is sensed along with the graphic display of respiration.

• peripheral nerve stimulator

"Nero Fiddled While Rome Burned." try to prevent emergence of Neros within us

• In remote areas, where darkness and big machines prevails, ETCO2 can be very helpful.

• If possible, mobilise end-tidal CO2 monitoring from the operating theatres.

• Monitoring may be a particular challenge in the MRI suite

DON’T DONATE THE ETT TO SURGEON…

• Certain procedures require circuits and monitors with long extension tubings e.g. Interventional neuroradiology….

• An AMBU should also be available to provide positive pressure ventilation in case of oxygen failure.

ETCO2 if non intubated

CHALLENGESSTAFF

Lonely walk through dangerous paths!

• Staff trained only in their speciality • sole responsibility of the

anaesthesiologist to check and ensure safety

• ensure that rapid communication to colleagues in the main theatre suite is possible.

• identify an assitant to help • Check consent

Think , Plan and Communicate

• Think and plan the moment you get the call

• Anticipate problems before starting the case;

• Help from main theatre may be slow to arrive.

CHALLENGESPROCEDURE

Poor illumination

• Many procedures are carried out in darkened rooms

[e.g. interventional radiology or endoscopy]

• Should be able to visualise the flow meters and to check accurate gas flows.

• we must be vigilant to detect unexpected events such as cessation of oxygen delivery and ETT disconnection

WEL[L]COME……. We have arranged a very nice trap , both for you and our patient….• Beware of the situation where the

anesthesiologist is called after the intervention has started and the patient is found to be uncooperative.

• Without a prior plan or airway assessment the situation is hazardous – if situation allows, it is better to abort the procedure and come back another day when things can be planned properly.

The extremes…!

• Some areas are poorly equipped to deal with any kind of emergency

• E.g. Burn dressings, muscle biopsies etc done at bedside

Positioning

• Patients undergoing ERCP, Endoscopy and CT guided biopsies lateral or prone position.

• ? pillows are available for safe prone positioning ? All other routine precautions for prone position..

• Prone position becomes difficult if the patient requires routine resuscitation – reposition the patient rapidly if this is the case.

Duration of the procedure

• Duration : difficult to predict • They may finish very abruptly :

Avoid long-acting muscle relaxants and maintain close communication with the specialist performing the procedure.

Post-procedure care

• Transport to a standard recovery room with the monitors along with the anaesthesiologist

• oxygen during transport. • Patients who require elective

postoperative ventilation must be transferred with continuous monitoring

Post-procedure care

• Patients undergoing aneurysm coiling may need to be ventilated in the postoperative period.

• The availability of an ICU bed has to be confirmed prior to the procedure.

SOME SPECIAL CONSIDERATIONS

• Anaphylaxis to iodinated dyes is possible. All the drugs for Rx of anaphylaxis should be immediately available.

• Radiation exposure - anaesthesia personnel should be aware of the radiation hazards and take precautions to avoid radiation exposure.

• Intermittently check, whether your syringe pump is running and adequate amount of drug is remaining, 3-ways are turned in the proper direction, breathing pattern is normal,

CHALLENGESPATIENT

Dealing with the most important person in any setting...

• the reason for which they require the intervention,

• associated co-morbidities. • Fasting status • a quick airway assessment :

unanticipated difficult airway is very challenging in remote

• Presence of dentures

I won't cooperate man.......

• Children• anxious patients• Claustrophobic patients (especially in

MRI suites) • • Elderly or confused patients • Patients undergoing painful procedures • Patients requiring burns dressings.

ANAESTHETIC TECHNIQUE

CHOICE OF ANAESTHESIA

• Monitoring only [do not require an anaesthesiologist]

• Sedation• Regional anaesthesia• Total intravenous anaesthesia• General anaesthesia.

Sedation/anagesia: easier ; but ensure frequently that you are not in trouble!

• less invasive • cost and time saving• high rate of failure• high chance of airway and

respiratory depression

Definition of general anesthesia and levels of sedation /analgesia [Approved by the ASA,2009]

MAINTAIN THE BALANCE…

• The degree of safety in conscious sedation is much higher than deep sedation.

• The patient can easily drift from a state of conscious sedation to deep sedation, depending on his age, sensitivity to drugs, health status etc.

• Titration and adjustment of the doses of the sedative agents requires skill and experience.

Total intravenous anaesthesia (TIVA)

• Drugs are used intravenously, for hypnosis and analgesia.

• Airway chin lift/jaw thrust / an oropharyngeal airway / LMA may be used if the patient is deeply anaesthetised.

• oocyte retrieval, in vitro fertilisation and foetal reduction in ultrasound rooms usually fentanyl + propofol

General Anaesthesia

E.g. Interventional Neuro radiology, MRI suite etc

tracheal intubation / LMA best prevention of motion invasive, time and resource

consuming atelectasis

…….Regional anaesthesia

• Combined spinal-epidural anaesthesia e.g. for EVAR - Endovascular aneurysym repair.

• The conscious patient can communicate and this is a major safety consideration.

DOCUMENTATION OF ANAESTHESIA

• A time-based anaesthesia flow sheet • Drugs administered – time and dose• SaO2 , Heart rate , Respiratory rate , NIBP –

can omit if minimal sedation, e.g. during MRI/CT

• Level of sedation• Observations should be performed at 15

minute intervals for conscious sedation, and 5 minute intervals for deep sedation and general anaesthesia.

HAZARDOUS

IF OMITTEDFOR ANAESTHETIST

CHOICE OF DRUGS

• This depends on the procedure being performed, and whether this is painful or painless.

• e.g. MRI scan compared to endoscopy compared to a change of burns dressings.

DRUGS• Midazolam: In paediatric

patients, intranasal midazolam has also been tried successfully.

• Fentanyl : 0.25-0.5mcg.kg-1 is usually sufficient.

• Propofol : A careful and slow intravenous injection of propofol is an ideal choice.

• Ketamine• Ketofol: provides good

hemodynamic stability.• Remifentanil : An ideal drug

but not available in India • Prilox cream

DEXMEDITOMIDINE

PROPOFOL- an easy method…. Load with 2 mg/kg over 10

minutes in a 50 mL syringe-pump

For e.g. 10 kg child: 20mg=2mL X 6 = 12mL/hr (for first 10 mins) ; then…

If you set the maintenance as half this dose (i.e. 6 mL/hr)

This will be equivalent to 100 ug/kg/min infusion of propofol…..

There is substantial variability in the response to each agent betweenindividuals.......

Change your tactics according to the ‘opponent’.

. ASA guidelines for NORA patients.

Discharge criteria

Anesthesia for MR IMAGING• .

Contrast media

• Allergic reaction• History• Symptoms: skin reactions,

airway obstruction, angioedema, and cardiovascular collapse.

• Treatment: corticosteroids, H1 and H2 blockers. Oxygen, epinephrine, β2-agonists, and intubation , IV fluids

• Prevention: corticosteroids

Anesthesia for CT

• Less complex• Use standard monitoring• Less anesthetic time• Higher levels of radiation

exposure

Anesthesia for MRI-Physical environment

• High magnetic field• Uncertain duration • Need specialized compatible

equipment • Radiofrequency noise• Metallic implants or

implanted devices• Patients with implanted

pacemakers, ICDs, or pulmonary artery catheters may not have

MRI scans.

Special circumstances - Magnetic resonance imaging (MRI)

• NEVER take any ferrous metal into the MRI suite – includes laryngoscopes, scissors and stethoscopes and mobile phones.

• In an emergency, take the patient out of the MRI room, do not take the emergency equipment to the patient.

• can keep noise blockers in patients ears

Dedicating these two things to those who sacrificed theirs’ for MRI Machines .

MRI- Conduct of anaesthesia

• In the MRI centre Anaesthesia is induced outside the MRI room and the patient is transferred to the MRI compatible machine in the room.

• Slave monitors must always be kept outside the MRI room.

• From these monitors we can see the respiratory tracing, ETCO2, PR, BP etc

Drugs for paediatric age group for MRI

MRI SUITE

Electroconvulsive therapy (ECT)

• Mainly to treat major depression• Typically, ECT is performed twice

weekly until there is a lack of further improvement [6 to 12 treatments over 2 to 4 weeks]

• Physiologic effects: > a grand mal seizure tonic phase :

10 to 15 s, >clonic phase :30 to 50 s.

Electroconvulsive therapy (ECT)

• > first reaction: parasympathetic discharge lasting 10–15 s. This can result in bradycardia, hypotension, or even asystole

>following reaction: hypertension,arrhythmias, tachycardia, lasts for 5-10min↑O2 consumptionM.I.

Left ventricular systolic and diastolic function can remain decreased up to 6 h after ECT

ICP, intraocular and intragastric pressure increase

Contraindication :

• absolute contraindication: intracranial hypertension

• Relative contraindications:Untreated intracranial mass,aneurysm, within 3 months of either a MI or cerebrovascular accident, uncontrolled cardiac failure untreated glaucoma unstable major fracturethrombophlebitis, pregnancyretinal detachment, DVT (until anticoagulated)severe osteoporosis, phaeochromocytoma,Cochlear implants

ECT-Anesthetic goals

1. amnesia and rapid recover2. Prevent damage 3. Control hemodynamic

response. 4. Avoid interference with

initiation and duration of induced seizure.

Anaesthetic technique

No Sedative premedication Patients should be encouraged

to empty their bladder as incontinence is common

Standard monitors (ECG, SPO2 , BP)

Place rolled gauze pads

U R THE , NOT THE DRUG

Objective : a rapid onset and offset of both unconsciousness and muscle relaxation for the duration

All currently available induction agents are suitable for ECT , except ketamine.

Whichever drug is used, it is preferable to utilize the same one throughout a course of treatment to avoid interfering with the seizure threshold (which generally increases over a course of ECT).

Was there 4 quite some time; now a hero!

Preoperative α-2 agonists such as dexmedetomidine also blunt the hyperdynamic response as does glyceryl trinitrate, which should be considered in patients at high risk of myocardial ischaemia.

Can use labetalol or esmolol when necessary.

Done it!

Succinylcholine (0.5 mg kg−1) is most commonly used. Larger doses up to 1.5 mg kg−1 may be required

Glycopyrrolate has superior anti-sialogogue effects, no adverse central nervous system effects, and results in less post-ECT tachycardia.

Routine atropine premedication is not recommended due to detrimental effects on myocardial work and oxygen demand.

Deleterious sympathetic effects may be controlled with β-blockers either pre- (atenolol) or intra-procedurally (labetalol and esmolol)

Intubation- not routinely required, ventilation can be gently assisted with a face mask.

Hyperventilation lowers the seizure threshold and can prolong seizure duration.

a bite block protects the patient's teeth, lips, and tongue.

During initial treatments, the stimulus magnitude may be titrated until an adequate seizure is generated. In such circumstances, further boluses of induction agent are required to maintain anaesthesia.

ECT- adverse effects• confusion, agitation, violent

behaviour, amnesia, headache, myalgia, and nausea and vomiting.

• Emergence agitation can be the most challenging problem to treat.

• Small doses of midazolam may be useful if simple measures such as a secluded, calm recovery environment do not help.

• The presence of a trained escort familiar to the patient can be reassuring.

ECT- adverse effects• arrhythmia • myocardial infarction • laryngospasm • aspiration• Transient ischaemic deficits,• intracranial haemorrhage, • cortical blindness• status epilepticus; Terminate seizure

with propofol or benzodiazepines within 3 minutes

• Disorientation, • impaired attention, and • memory problems

What anaesthesia you ve given? Patient is disoriented…..

Anesthesia for neuroradiologic procedures• A. Endovascular embolization

• Indication: cerebral aneurysms, arteriovenous fistulas and malformations , vascular tumors

• Methods: femoral artery puncture, a small catheter into the aneurysm

• Anesthetic goals :stable hemodynamics, and rapid recovery

• Other problem: Invasive arterial blood pressure monitoring , avoid hypertension, monitor anticoagulation, complications include rupture of the aneurysm

OTHER NEURO RADIOLOGICAL INTERVENTIONS

B. Embolization for control of epistaxis and extracranial vascular lesions C. Balloon occlusion testD. Cerebral and spinal angiography E. Vertebroplasty and kyphoplasty F. Thrombolysis of acute strokeG. Cerebral vasospasm

ESWL CONCERNS• PAIN: stinging,sharp• [1] @cutaneous level +

visceral and [2] due to the movement of the stone

• CLAUSTROPHOBIA• GA usually not necessary• Spinal / epidural • NSAIDS, PARACETAMOL,

FENTANYL, EMLA cream for analgesia + MIDAZOLAM may suffice

• Need to mobilize the operating table

• Ensure in the operating position, you can access for any emergency intervention

Upper and lower endoscopy and ERCP

Others interventions requiring NORA

• Anesthesia for vascular, thoracic, and gastrointestinal/genito-urinary radiology procedures.

• Anesthesia for cyclotron therapy and radiation therapy/brachytherapy

THANK YOU

Visit me @

www.thelaymedicalman.blog spot.comFACEBOOK page “Anaesthesia Info from the Lay Medical Man”

References• Updates in Anaesthesia ,Volume 25 Number 1 June 2009,

Anaesthesia Outside the Operating Theatre Lakshmia Jayaraman*, Nitin Sethi, Jayashree Sood

• Anaesthesia for electroconvulsive therapy,Vishal Uppal,

Jonathan Dourish, Alan Macfarlane, oxfordjournals.org

NON OPERATING ROOM ANAESTHESIA

Health & Medicine