Surg 102 Chapter 24 (B&K)--Part 2 Flashcards
Apply pressure to the _____ to occlude the esophagus and immobilize the trachea.
cricoid cartilage
Applying pressure to the cricoid cartilage is also called the _____.
Sellick’s maneuver
The Sellick’s maneuver prevents _____ and _____ of stomach contents.
regurgitation and aspiration
Compression of the cricoid cartilage must continue until the _____ is inflated and the anesthesia provider states that it is safe to release pressure.
endotracheal tube cuff
An _____ is performed before the induction of general anesthesia.
awake intubation
What are the most common indications for awake intubation?
acromegaly, anterior larynx, an enlarged tongue, a limited oral cavity, jaw fixation, a short neck, and limited cervical range of motion
The conditions that lead to an awake intubation may inhibit visualization of the vocal cords by direct laryngoscopy and thus increase the potential risk of _____.
airway obstruction
Awake intubation can be performed with a _____ or _____ for direct visualization of vocal cords.
fiberoptic or rigid laryngoscope
What are the five objectives of general anesthesia?
- oxygenation
- unconsciousness
- analgesia
- muscle relaxation
- control of autonomic reflexes
Oxygenation (as an objective of general anesthesia):
tissues, especially the brain, must be continuously perfused with oxygenated blood
Unconsciousness (as an objective of general anesthesia):
the patient remains asleep and unaware of the environment during the surgical procedure
Analgesia (as an objective of general anesthesia):
the patient must be free of pain during the surgical procedure
Muscle relaxation (as an objective of general anesthesia):
must be constantly assessed to provide necessary amounts of drugs that cause skeletal muscles to relax
Control of autonomic reflexes (as an objective of general anesthesia):
anesthetic agents affect cardiovascular and respiratory systems; tissue manipulations and systemic reactions to them may be altered by drugs that control the autonomic nervous system
All anesthesia machines have the following features:
- sources of oxygen and compressed gases
- means for measuring (flowmeters) and controlling (reservoir bag) delivery of gases
- means to volatilize liquid (vaporizer) and deliver (breathing tubes) anesthetic vapor or gas
- device for disposal of carbon dioxide
- safety devices
Safety devices on an anesthesia machine include the following:
- oxygen analyzers
- oxygen pressure interlock system (to shut off the flow)
- end-tidal carbon dioxide monitor
- pressure and disconnect alarms
- gas scavenger system
The method for administration of inhalation anesthetics through the anesthesia machine can be classified as _____, _____, _____, or _____.
semi-closed, closed, semi-open, or open
As it pertains to administration of inhalation anesthesia, describe a semi-closed system.
- most widely used
- permits exhaled gases to pass into the atmosphere so that they will not mix with fresh gasses and be re-breathed
- induction is slower but with less loss of heat ans water vapor that with open methods
As it pertains to administration of inhalation anesthesia, describe a closed system.
- allows complete re-breathing of expired gas
- exhaled CO2 is absorbed by soda lime or a mixture of barium and calcium hydroxide (Baralyme) in the absorber of the machine
- provides maximal conservation of heat
- reduces the amount and therefore cost of agents
- reduces environmental contamination
As it pertains to administration of inhalation anesthesia, describe a semi-open system.
- some exhaled gas can pass into surrounding air but some returns to the inspiratory part of the circuit for re-breathing
- degree of re-breathing is determined by the volume of flow of fresh gas
As it pertains to administration of inhalation anesthesia, describe an open system.
- valves direct expired gases into the lower portion of the canister, where they are removed by vacuum
- patient inhales only the anesthetic mixture delivered by the anesthesia machine
Anesthetic gas or vapor of a volatile liquid is inhaled through a _____ attached to the anesthesia machine by breathing tubes.
face mask
An airway can be maintained by inserting a _____ into the larynx.
laryngeal mask airway (LMA)
A laryngeal mask airway is a flexible tube that has an _____ silicone ring and cuff.
inflatable
When the cuff of the laryngeal mask airway (LMA) is inflated, the mask fills the space around and behind the _____ to form a seal between the tube and the _____.
larynx
trachea
Advantages of endotracheal administration of anesthetic vapor or gas are:
- ensures a patent airway and control of respiration
- secretions are easily removed from the trachea by suctioning
- protects the lungs from aspiration of blood, vomitus of gastric contents, or foreign material
- preserves the airway regardless of the patient’s position during the surgical procedure
- interferes minimally with the surgical fields during head and neck procedures
- helps minimize the escape of vapors or gases into the room atmosphere
Potential complications of endotracheal administration of anesthetic vapor or gas are:
- trauma to teeth, pharynx, vocal cords, or trachea
- cardiac dysrhythmias
- hypoxia and hypoxemia
- accidental esophageal or endobronchial intubation
- aspiration of gastrointestinal contents
Controlled respirations can be defined as the _____.
completely controlled rate and volume of respirations
Assisted respiration implies that the patient’s own _____ effort initiates the cycle.
respiratory
When is controlled aspiration is initiated?
after the anesthesia provider has produced apnea by hyperventilation or administration of respiratory depressant drugs or a neuromuscular blocker
Advantages or controlled respiration are:
- provides for optimal ventilation
- allows for selective lung deflation for thoracic procedures
- provides access to deep regions of the thorax and upper abdomen
- permits deliberate production of apnea to facilitate surgical manipulation below the diaphragm, ligation of deep vessels, or obtaining radiographic films
Nitrous oxide (N20)–Inhalation agent
Advantages
1. nonvolatile
2. rapid induction
3. pleasant, fruit-like odor
4. incidence of nausea and vomiting minimal
Disadvantages
1. can cause bowel distension and increased volume in other air pockets
2. can cause displacement of tympanoplasty grafts or increased intercranial pressure
Halothane (Fluothane)–Inhalation agent
Advantages 1. rapid with smooth induction Disadvantages 1. potentially toxic to the liver 2. has profound effect on body temperature control (may cause hypothermia)