Chapter 9_ Anesthesia

Reversal of muscle relaxants agents

"anticholinergics" atropine robinul

MH triggered by

-Use of succinylcholine, curare, halogenated inhalation agents -Strenuous exercise, stress, trauma

Physical status codes

ASA 1: normal healthy pt ASA 2: mild systemic disease that's controlled and doesn't limit activities ASA 3: moderate to severe systemic disease, possibly uncontrolled, can alter activities ASA 4: severe systemic disease that is a constant threat to life ASA 5: morbid and substantial risk of death within hours with or without intervention E: emergency status or undergoing emergency procedure (added to ASA code)

Risks of General Anesthesia

Aspiration Cardiac dysrhythmias Cardiac arrest Laryngospasm/ Bronchospasm Allergic reactions Shock Malignant Hypothermia

Patients hard to intubate

COPD, asthmatic -Need respiratory treatment first

Anesthetic state

Characterized by unconsciousness and insusceptibility to pain produced by anesthetic agent or combination of agents

Narcotic analgesics

Controlled substances given to minimize perception of pain and to potentiate anesthesia; usually given 1 hour prior to surgery in order to have peak effect Ex. Demerol, morphone

Selection of anesthesia based on:

Current physical status Presence of metabolic disease Psychological status Type and length of procedure Past history of adverse reactions Preference of doc, pt

Histamine 2/ antacid blockers

Decrease gastric acidity and volume Ex. Tagamet, Zantac, bicitra

Agent inhalation

Delivery of gases that cross the Alveolar membrane to the vascular system where the agent can affect the CNS functions

Airway management

Endotracheal tube Laryngeal airway mask Oropharyngeal airway Nasopharyngeal airway Nasal cannula Oxygen mask

Non traditional anesthesia options

Hypnoanesthesia Acupuncture

Phase 1: Induction

Induction agents, IV agents or Inhalation agents are administered and loss of consciousness occurs and usually a muscle relaxant. Management of Airway is critical and may involve ET tube, nasal airways, or a laryngeal mask airway, or face mask -pt hearing is last to go

Halothane/ Fluorthane

Inhalation Agent Volatile liquid used for rapid smooth induction, -Causes bronchodilation, shivering, liver toxicity, -Contraindicated for C-section -d/t smooth muscle relaxation

oropharyngeal airway (OPA)

Inserted I guess to prevent tongue or epiglottis from falling back against pharynx, for pts with respiratory function but need airway support Pts are semi conscious

arterial line

Invasive radial or femoral entry monitors B/P

Pulmonary artery catheter

Invasive right atrium entry monitors cardiac output, PCWP also called Swan-Ganz

esophageal probe

Invasive temperature monitor listen to heart/lung sounds

Endotracheal tube

Invasive airway that extends from the mouth to the trachea, with a rigid laryngoscope

Assistive devices

Laryngoscopes Magill forceps Styles Oral/ nasal airway Nerve stimulator

Inhalation Agents

Oxygen Nitrous Oxide Halothane Enflurane Isoflurane Desflurane Sevoflurane

Preoperative evaluation

Perform assessment to determine pt specific needs and risk factors

General Anesthesia aka

Peripheral nerve block

Shock treatment

Plasma expander Dextran Trendelburg position

Hypnotic drugs

Produce varying levels of hypnosis from light to more natural sleep of sedation to full unconsciousness of General anesthesia

antianxiety drugs

Reduce anxiety, are antiemetic, antihistamine, potentiate anesthesia Ex. Phenergan, Valium, Ativan, versed

Antiemetic drugs

Reduce nausea and vomiting Ex. Reglan, zofran, droperidol

What helps place endotracheal tubes?

Stethoscope

Amnesia permits:

Use of safe, less toxic anesthetic agents and techniques while providing a calm and cooperative patient

sensation

ability to feel stimuli in the environment

Cardiac dysrhythmia

abnormal heart rate or rhythm (atrial or ventricular)

Shock

abnormal physiological state indicated by presence of reduced cardiac output, tachycardia, hypotension, diminished urinary output

analgesia

absence of pain produced by drugs

cyanosis

blue or dusky hue of skin

coma

deepest state of unconsciousness where most brain activity ceases

antagonist

drug that counteracts the effects of another agent or physiological process

sedative

drug that induces a range of unconscious states

agonist

drug that potentiates the release or uptake (or both) of other medications

anxiolytic

drug that reduces anxiety

anesthetic

drug that reduces or blocks sensation or induces unconsciousness

Desflurane/ Suprane

has pungent aroma, has more rapid onset and recovery, safe to use with liver disease

Maintenance agents given

inhalation agents nondepolarizing neuromuscular blocker analgesic/ opiod reversal agents

another name for Spina anesthesia

intrathecal

Malignant Hypothermia more common in

males

Sir Ivan Whiteside Magill

many styles of endotracheal tubes and laryngoscopes are based on his designs

Monitored Anesthesia Care (MAC)

monitoring of vital functions during regional or local anesthetics to ensure the pts safety and comfort

fasciculation

muscle twitching

IV Agents

narcotics/ Analgesic sedatives/ tranquilizers atropine sulfate succinylcholine hydrochloride morphine sulfate alfentanil fentanyl demerol

protective reflexes

nervous system response to harmful environmental stimuli like pain, obstruction of airway, extreme temperature, coughing, blinking, shivering, withdrawal

Stage I: AMNESIA

pt is conscious and with administration (induction) of anesthetic agent moves to loss of consciousness -received propofol, succinylcholine

Enflurane/ Ethrane

rapid induction and recovery, used for maintenance of anesthesia

Isoflurane/ Forane

similar to halothane and enflurane

Allergic reactions

skin irritation or anaphylaxis (immediate hypersensitivity) reaction, can result in life threatening respiratory distress that leads to vascular collapse or shock

homeostasis

state of balance in physiological functions

Goal of surgical anesthesia

to allow the pt to tolerate surgery and maintain the body in a balanced physiological state (homeostasis)

CRNA- Certified Registered Nurse Anesthetist

trained and licensed to administer anesthetic agents

doppler

ultrasonic device assess vascular sounds

General Anesthesia accomplishes:

unconsciousness analgesia amnesia muscle relaxation maintains homeostasis

balanced anesthesia

use of multiple drugs to produce sedation, analgesia, amnesia, and muscle relaxation during general anesthesia

Sevoflurane

used for pediatric anesthesia, rapid induction and recovery

Agent instillation

Administration of mediation's into areas where it can be absorbed such as the rectum, vagina, mucous membranes

Agent injection

Administration of medications directly into the blood stream via IV

Hypnosis

Altered state of consciousness, related to the pt perception of the surgical environment and the surgical procedure

Physical status codes established by

American Society of Anesthesiologists

Preoperative checklist

Chart Identity Correct procedure, site, side Consent forms Resuscitation orders Allergies Preop meds Prostheses & Jewelry removed Medical records Test results CBC Coagulation studies ECG Chest X-ray

Laryngeal airway mask (LMA)

Manages airway without laryngoscope, fits over larynx, used for pts with difficult airway conditions but doesn't protect against aspiration

Nerve blockers/ esters

Tetracaine Pontacaine

Epidural Anesthesia

agent is injected into epidural space, before the Dura, and infuses into spinal cord. Catheter placed and taped to pt back. Lumbar Caudal * commonly used in obstetrics/ C section * slower onset but longer duration and can be titrated

Anticholinergics

Used to block secretions, prevent laryngospasms, prevent reflex Bradycardia ( can cause dry mouth and not for glaucoma pts) Ex. Atropine, robinul

NON-depolarizing muscle relaxant

Used to maintain relaxation during surgical procedures atracurium/ tracrium cisatracurium/ nimbex mivacurium/ mivacron rocuronium/ zemuron vecuronium/ norcuron

Sedative/tranquilizer/ amnesia agents

Versed Valium

Phase 4: Recovery

Vital signs are stable, oxygen needs to be on pt, pt returns to optimum level of consciousness. Usually begins in the OR and follows in PACU. -monitoring is still important -sounds heard

anesthesia

absence of sensory awareness or medially induced unconsciousness

Spinal Anesthesia

agent is injected into subarachnoid space and anesthetizes spinal motor nerve roots, eventually enters bloodstream -fast induction but shorter lived than epidural

Regional Anesthesia

aka Peripheral Nerve Block injection site is proximal to surgical site

Anesthesia technician

allied health professional trained to assist the anesthesia care provider

general anesthesia

alteration in the patients perception of their environment through alterations in their level of consciousness

Sedatives used for

amnesia, hypnotic effects

airway

anatomical passageway or artificial tube through which the pt breathes

topical anesthesia

anesthesia of superficial nerves of skin or mucous membranes

regional block

anesthesia to specific area of body achieved by injection of an anesthetic around a major nerve or group of nerves

Inhalation Anesthesia

anesthetic agents are inhaled and pass to the blood stream through pulmonary function -Non-flammable -rapid acting

Epidural most commonly used for:

anorectal vaginal perineal lower abdomen lower extremities

Treat Cardiac ventricular fibulation/ amides

anti arrhythmic Lidocaine HCL Xylocaine HCL

parasympathetic nervous system (PNS)

part of autonomic nervous system responsible for energy conservation and rest, relaxation of muscle groups, dilation of blood vessels and decreased blood pressure

Stage III: SURGICAL ANESTHESIA

period between onset of regular breathing and loss of eyelid reflex to cessation of breathing. Pt is unresponsive to painful stimuli and sensations, allowing incision to be made and procedure performed without negative response

apnea

period of cessation of breathing

Stage II: EXCITEMENT or DELIRIUM

period of loss of consciousness to return of regular breathing and loss of eyelid reflex. Pt still responding reflexively and unpredictably to certain stimuli; uninhibited movements -may experience vomiting, laryngoscope, hypertension, tachycardia -use Sellick manuever

ventilation

physical act of taking air into the lungs by inflation and releasing CO2 from lungs by deflation

Fight or Flight response (SNS response)

physiological reaction includes diversion of blood to essential organs, increased heart rate and BP

how is patient tested for level of spinal anesthesia

pinpricked

Michael Jackson drug

propofol

Pre-Induction Phase

pt arrives in OR calm and stable, ACP attaches monitoring devices (vital signs, EKG) and pre-oxygenates patient

malignant hypothermia (MH)

rare but life threatening reaction in which an inherited muscle condition causes a hyper-metabolic state in patients exposed to specific trigger agents; experience deficit in calcium transportation within the skeletal muscle fibers

intraoperative awareness (IOA)

rare condition where a pt undergoing general anesthesia is able to feel pain and other stimuli but unable to respond

bier block

regional anesthesia where the anesthetic is injected into a vein

sedation

rousable state in which an individual is unaware of sensory stimuli Depression of the CNS

Laryngospasm/ Bronchospasm

slight trigger of the gag reflex results in spasm or rigidity of the upper respiratory tract; can be triggered by saliva at back of throat, stimulation of lightly anesthetized pt, inflammation from ET tube placement

LMAC

Local Monitored Anesthesia Care

Advantages of Inhalation Anesthesia

-Depth of A can be monitored and rapidly adjusted to alter depth -Gas or vapor is directly exposed to pulmonary circulation allowing for more rapid manifestation

Induction Agents and IV Anesthesia

-combination of drugs used -permits a rapid and pleasant transition from a state of consciousness to unconsciousness -provide sedation and amnesia

Advantages of General Anesthesia

-pt unaware of activities and noises associated with operation -depth and rate of respiration can be controlled & pulmonary tree is usually protected from aspiration (once airway established) -medications can be easily titrated -muscle relaxation for intubation and retraction at the surgical site is easily achieved

Signs of MH

1st unexplained tachycardia followed by tachypnea, increased CO2 levels, unstable BP, perspiration, muscle contraction, cyanosis, mottled skin, increased temperature

role of ST in Circulator role

Assist during intubation (Sellicks manuever) Assist applying monitoring devices Maintain quiet environment Know equipment and use Know where shock cart and emergency supplies are kept Be attentive Help transport and position patient Ask ACP before performing anything on pt, removing instruments (post op)

Monitored Anesthesia Care

Local/ nerve block (light sedation, no intubation/gas) Need 2 RN's Patient is awake (twilight anesthesia) For Extremities

BIS monitor

Bispectral Index System Noninvasive monitors level of consciousness (LOC) and prevent intra-operative awareness, try to keep it under 60

preoperative anesthesia interview

Confirm use/type/amount of prescription drugs, alcohol, tobacco, and illegal drugs Prior surgeries and complications experienced Family history of anesthetic complications Record vital signs Evaluate airway Examine organ systems in question

Sir Ivan Whiteside Magill

Developed and refined techniques of endotracheal intubation (namesake: Magill forceps for anesthesia)

Induction Agents

Diprivan (propofol) Amidate Pentothal Sodium Brevital

Treatment of MH

Discontinue anesthesia administration Turn of inhalation agent Give 100% oxygen Non-triggering agent given (Dantrolene) Chilled saline and ice packed into cavities

Sir Ivan Whiteside Magill

First anesthetist to describe technique of blind nasal intubation

Types of anesthesia

General Nerve Conduction blockade Topical Local Regional

4 Stages of Anesthesia

I- Amnesia II- Excitement or delirium III- Surgical anesthesia IV- Overdose

Oxygen

Inhalation Agent essential for pt, helps to maintain good O2 sats; green tank

Nitrous Oxide

Inhalation Agent laughing gas used adjunct to IV anesthesia; blue tank

General anesthesia accomplished by:

Inhalation agent Injection agent Instillation agent

Reverses Versed or Valium (sedatives)

Mazicon Flumazenil

MAC

Monitored Anesthesia Care

Reverses Opioids & Narcotics (like Demerol)

Narcan Revex

Oxygen delivery by

Nasal cannula, oxygen mask

Types of Regional Anesthesia

Nerve Plexus block Bier block Spinal Block Epidural Anesthesia

Types of Nerve Conduction Blockade agents

Nerve conduction blocking Amino amid group Amino ester group Adjunctive

Muscle relaxation

Neuromuscular blockers in combination with inhalation agents are capable of producing a profound muscle relaxation, permitting tracheal intubation and ability to work in certain areas

Nondepolarizing muscle relaxer

Norcuron Tracrium Pavulon

How to control level of spinal anesthesia

Patient positioning: Lateral Sitting * arch back like "mad cat"

Phases of General Anesthesia

Pre-Induction 1. Induction 2. Maintenance 3. Emergence 4. Recovery

Sedative/ amnesia drugs

Promote sleep and lack of memory Ex. Versed, Valium, ativan

Sedative/ hypnotic drugs

Promote sleep and reduce anxiety, can cause hallucinations Ex. Phenobarbital, ketamine

Sedation/ anesthesia Induction agents

Propofol Diprivan

Nasopharyngeal airway

Provide passageway between nostril and nasopharynx. Pts are semiconscious, gagging, or mouth injury present

Advantages of Spinal

Pt awake so control airway Non-irritating to respiratory tract Blockade of PNS and SNS Produces bowel contractions Facilitates abdominal exposure produces excellent muscle relaxant

halogenated

The danger of fire in the OR has been reduced with the introduction of which kind of anesthetics?

Agents that reduce secretions, treat bradycardia

anticholinergic Atropine Robinul

Phase 2: Maintenance

begins after insertion of airway and continues through surgical intervention until end of operation -pt monitoring is critical -surgical interventions can change pt status

Preoperative agents given

benzodiazepines (sedation and amnesia) anticholinergic (inhibit secretions, increase heart rate) antacids antiemetics

gas scavenging

capture and safe removal of extraneous anesthetic gases from the machine

Cardiac arrest

cessation of heart pumping action and blood circulation

Horace Wells

dentist that used nitrous oxide for teeth

Induction agents given

depolarizing muscle relaxant hypnotics

sedatives (agents)

diazepam/ valium midazolam/ Versed ketamine/ ketalar

cricoid pressure

direct manual pressure on the cricoid cartilage to prevent aspiration and facilitate intubation -Also called "Sellick Maneuver"

Reversal NeuroMuscular blocking agents

edorphonium neostigmine

Phase 3: Emergence

end of surgical procedure anesthetic gases are discontinued and allowed to wear off. Process of regaining consciousness. -pt begins breathing on own, ET tube extubated, start hearing again

James Simpson

introduced chloroform to anesthesia

bronchospasm

involuntary smooth muscle spasm of bronchi

John Snow

first anesthetist

Crawford Long

first to use ether during a surgical procedure (tumor removal) 1842

infusion

giving a drug over a specified period

Aspiration

greatest during induction and emergence phase leading to aspiration pneumonia -use Cricoid pressure (Sellick Manuever) to prevent

Nerve Conduction Blocks

involves use of pharmaceutical agents to prepare the transmission of sensory nerve impulses

amnesia

lack of recall of events or sensations

regional anesthesia agent chosen by:

length of procedure level of block needed pt condition and health

Stage IV: OVERDOSE

level of anesthesia so deep that cardiovascular and respiratory function is compromised to the point of collapse due to depression of those centers in the brain -characterized by dilated or nonreactive pupils and major drop in BP -experience shock, neurological issues - if uncorrected this stage will lead to pt death

ACP- Anesthesia Care Provider

licensed to administer anesthetic agents, manage the pt through out anesthesia, & respond to anesthetic and surgical emergencies

anaphylaxis

life threatening allergic reaction to a drug or substance

unconsciousness

neurological state where one is unable to respond to external stimuli

consciousness

neurological status in which a pt is able to SENSE environmental stimuli (touch, sound, pain, pressure, heat, cold)

nerve stimulator

noninvasive assesses muscle relaxer effectiveness

EKG/ECG

noninvasive detects arrhythmia AKA electrocardiogram

capnography

noninvasive measures end-tidal CO2 levels

pulse oximetry

noninvasive monitors oxygen level

spirometry

noninvasive monitors ventilation volume, pressure

pulmonary embolism (PE)

obstruction in a pulmonary vessel by a blood clot, air bubble, or foreign body causing sudden pain or possible pulmonary arrest

Sympathetic Nervous System (SNS)

part of autonomic nervous system responsible for Fight or Flight response to danger or stress

Disadvantages of Spinal Anesthesia

spinal headache hypotension parasthesia/ paralysis (temporary)

hypothermia

subnormal temperature

depolarizing muscle relaxant

succinylcholine, anectine, quelicin -can cause fasciculations, temporary paralysis, MH

Stages of Anesthesia

the patient passes through stages from consciousness to deep surgical anesthesia. They are based on physiological effects (body movement, respiratory rhythm, oculomotor reflexes, muscle tone)

Nerve block agents

xylocaine/ lidocaine carbocaine/ mepivacaine marcaine/ sensorcaine duranest/ etidocaine pontocaine/ cetacaine