anesthetic complications Flashcards
What are common complications that may occur in an anaesthetised patient?
Common complications include:
* Hypoxaemia/cyanosis
* Hypothermia
* Bleeding
* Respiratory arrest
* Cardiac arrest
What are the stages of hypothermia based on temperature range?
Stages of hypothermia:
* Mild: > 36.6 °C
* Moderate: 35.5-36.6 °C
* Severe: < 35.5 °C
Monitoring body temperature is essential to prevent hypothermia during anaesthesia.
What are the causes of hypothermia in anaesthetised patients?
Causes include:
* Prolonged anaesthesia time
* Anaesthetic drugs that downregulate the thermoregulation centre (eg methandone)
* Vasodilation (caused by drugs such as ace,alfax)
* IV fluids
* Clipping fur and surgical preparation
* Open body cavities
What are the consequences of hypothermia?
Consequences include:
* Decreased metabolism leading to decreased anaesthetic requirements (due to lower breakdown of drug, it stays longer in the body, leading to less anethetic drug needed to have patient asleep-> can lead to overdose, patient becomes too deeply anesthetised)
* Decreased immune response leading to Greater susceptibility to infection (cannot recruit cells,affects inflamation)
* Delayed wound healing leading to Higher risk for post-surgical complications (eg healing of incision-> bleeding) (lower blood flow)
* Bradycardia which affects oxygenation (decrease HR-> less blood being pumped around body)
* Decreased cardiac output leading to Hypotension and ischemia (less blooding traveling around body)
Decrease immune response
Decrease metabolism
Decrease cardiac output
Delayed wound healing
Bradycardia
What is the best approach to treat hypothermia?
Prevention is the best cure, which involves:
* Minimizing anaesthesia time
* Active warming techniques
-warming devices (air warmer, water warmer, infrared, electric +warmed fluid or rice bags +using warm IV fluids,using electric IV fluid warmer
What are some warming devices used to prevent hypothermia?
Warming devices include:
* Air warmer (blows warm air into chamber blanket)
* Water warmer (water is warmed through a machine then pumped through channels in the blanket)
* Infrared (heated through infrarer technology, temp controlled by numbered dial)
* Electric heat mat (heated through electrical heating coils)
Each device has specific features and efficacy in warming patients.
temperature of each warming device
air warmer: get to temp quickly, maintains temp well if insulated under blankey
water warmer: takes a long time to warm up, temp may fluctuate as water will cool rapidly
infrared: warms up rapidly, maintains temp well
electrical heat mat: warms up quickly,poor temp control, easily overheats
What are the risks associated with warming devices?
Risks include:
* Blanket puncture making it ineffective (air warmer, blanket referring to the thing the air is in)
* blankey may be punctured making it ineffective and wet-> Wet blankets poses a threat to asespsis and can cause electrocution (water warmer)
not monitored,
* can be set too high cauisng burns (inferared)
* can get hot very quickly causing burns (electric)
always ensure something is between warming device and patient-> to prevent burns
what are the different techiques for active warming
- warming devices
- warmed fluid bags/rice bags
- warmed iv fluid
- electrical iv fluid warmer
how to warm fluid/rice bags
use microwave
warm in 15s intervals
mix contents well and check temp
it should be warm, but not uncomfortable after 5-10s
always wrap in towel before placing next to patient
What is dyspnoea?
Dyspnoea is an abnormal respiration indicating an inability to obtain sufficient oxygen using normal respiratory effort. (looks like animal is havign difficulty breathing)
Recognizing dyspnoea is essential for immediate intervention.
What does cyanosis indicate?
Cyanosis refers to a blue/purple discoloration of skin and mucous membranes, indicating insufficient tissue oxygenation.
Monitoring for cyanosis is vital to assess oxygenation status.
what machine can tell us if there is dypsonea/ cyanosis
pulse oxymeter will shower SPO2 value < 94%
What are common causes of dyspnoea/cyanosis?
Common causes include:
* Equipment problems: empty 02 tank, flowmeter turned off, circuit damage
- Airway obstruction: ET tube bloackage, aspiration, underlying lung disease
- Excessive anaesthetic depth
EAE
Identifying the cause is crucial for effective treatment.
What initial steps should be taken if dyspnoea or cyanosis is detected?
(treatment)
Initial steps include:
* Check SpO2 reading (<94%?)
* Evaluate vital signs (HR,BR, MM colour)
* Determine anaesthetic depth (eyeball position, relfexes)
* Check anaesthetic setup for obstructions
turn vapouriser off, disconnect patient and flush system (remove any excess iso before supplying O2 to patient)
vantilate with 100% oxygen until MM colour (becomes pink) and SPO2 returns to normal (>95%)
monitor vital signs carefully
Quick assessment is critical for timely intervention.
What indicates hypotension?
Hypotension indicates insufficient tissue perfusion and is defined as:
* Systolic BP < 80 mmHg (normal 120)
* mean BP < 65 mmHg (normal 70-90) : means body will try to oxygenate to major org (heart, brain etc) -> less blood travelling to rest of the body, desp distal limbs)
Hypotension must be addressed promptly to prevent complications.
What are the common causes of hypotension during anaesthesia?
Common causes include:
* Excessive anaesthetic depth:
Cardiovascular depression from drugs
severity can be dose dependent
* Intra-operative bleeding
* Dehydration
* Hypothermia (cos of bradycardia)
Understanding these causes aids in prevention and management.
What is the treatment for hypotension?
Treatment includes:
* Reduce or turn off isoflurane
* Report to veterinarian: Administer IV fluid bolus
* Close monitoring of vital signs (BP ensure they are not getting worse)
Prompt treatment of hypotension is essential for patient stability.
What should be done if a patient stops breathing?
if just given IV induction-> it could just be transient apnea (usually lasts 15-30s so vital signs should still be ok)
not breathing spontaneously, Alert a vet immediately
* Measure vital signs,
* Provide 1 breath per 30 seconds if all vital signs are normal, do not overventilate as CO2 serves as a stimulant for spontaneous breathing)
respiratory arrests: abnormal vital signs
causes: anesthetic overdose, airway obstruction or diease
Avoid over-ventilation to prevent CO2 depletion.
causes of repiratory arrest
anesthetic overdose
airway obstruction/disease
What is the immediate response if cardiac arrest is suspected?
if a heartbeat cannot be detected by a stescope Immediate response includes:
* Turn off the vapouriser
* Call for help
* Assist the veterinarian as needed
Knowing basic CPR is essential for emergency situations.
what are some consideration when using electric IV fluid warmer to prevent hypothermia
insert iv line close to the patient into the device for a shorter distance between the warmed fluid and the patient-> fluid will be warmer when it reaches patient
common reasons for anesthetic complications
-age
-pre existing disease
-poor pre anethetic evaluation
-patient variation
-inexperienced anethetist
when does haemorrhage usually happen
most likely to happen after the patient is awake and blood pressure normalises-> (blleding now becomes more apparent) (post opp) (cos they awake, thier BP goes back to normal)
can vary greatly in severity (more stress-> higher BP-> more blood loss)
causes/risk factors of hemorrhage
-long complicated surgeries (esp on vascular opgans like spleen, liver)
-liver disease (production of coagulation factors)
-coagulopathiees (abnormal bleeding disorder-deficiency in platelts,enzymes, proteins)
-heparin therapy (anticoaggulant)
-inexperienced surgeon
-easily excitable pets (excited/nervious->increase in HR/BP-> more blood pumped out)
clinical signs of hemorrhage
-bleeding: dripping to gushing
-sudden bruising on skin (internal bleeding)
-palm mm
-lethergy
be aware that in early haemorrhage, you many not see anythign apart from bruising/mild seepage around the incision-> better get someone to check it out
how to prevent hemorrahage
- keep patient calm post-operatively
-ensure good pain management plan is in place
-utilise tranquilisers/sedative when required
-do not rouse patient from anethesia prematurely (can cause their BP to shoot up/ can fall back to sleep-> artificial) - close patient monitoring
-catching hemorrhage early can minimise severity. (cos it can happe suddenly (check immediately post opp, aft 30min, 1hr, right before they go home)
owners should be educated on what to look out for when patient is discharged
hermorrhage treathent
depends on severity
1. watch and wait
2. pressure bandage (to stop bleeding by forming clot)
3. re-anesthetize ans surgicly repair the bleeder (if pressure bandage doesnt work)
the process of recovering patient from GA
- turn of iso, oxygen remains on (to stop provision of anesthetic gas which is keeping the patient asleep)
- flush the anesthetic system ( off vapouriser, oxygen flowmeter on-> disconnect the patient via ET tube connector(prevent over inflation of patient lungs) -> cover end of anesthetic circuit(prevent cotamination of the environment) -> depress the oxygen flush valve to fill the reservior bag-> squeeze the reservior bag to empty it to ensure excess gas flows into the scavenger-> (remove excess anethetic gas in the system) repeat 2-3 times-> reattach patient via ET tube connector and maintain oxygen only)
3 - provide suplemental o2 fo several minutues ( dont have full control of their airway, reduce risk of aspiration-cos tube is still in)
- decuff and untie ET tube (faster for us to remove in an emmergency/ if pet wakes up suddenlu, can breathe normal room air-> a way that can stimulate them to wake up )
- after anrd 1min, turn off oxygen and disconnect patient (encourages the patient to breathe in normal air which facilitates the recovery process)
- monitor for return of swallowing reflex, 3 swallows before removing (to esnure that they have regained control of their airway). look out for movement of their throat
- Gently extubate (patient should be able to hold thier head up) (to prevent accidental trauma t airway/trachea when patient is able to swallow)
- patient to sternal recumbency (encourage to breath through both lungs, facilitate effective removal of iso in their lungs and facilite a more matural breathing method (if drool, it wont cause aspiration)
preparing to receive patient in ward
-good plan of care: (anes form, log all drug that may be needed, recoriding of their vital signs)
-surgical nurse handover to ward nurse (ward nurse is aware of what to expect/needed for patient recovery,update hosp chart/plan of care-> ensure all treatment is done in a timely manner, facilitate communication between team members)
pre emptive nursing (preparing ahead of time)
1.cage preperation: warm (heating pad), soft (blanket), quiet (dont want to stress them) and confortable (towels& iv fuid line)
2.maitain clean and dry env (any cleaning needed to be done before reciving patient)
TLC: verbal reassureance (speaking in a soft tone), gentle touch (to calm them down)
frequent check (vitals: HR,BR,BP, ensure its stable and returning back to normal) , ensure they are calm (risk opeing of incision, kinkin gof fluid line,pull out catheter)
describe the patient discharge procedure
contact owner: update about status (procedure complete/woken up/complications if any) + inform them what time to pick up, uodate on bill, answer any qns
-monitored for 3-4hrs (ensure that they are sufficently awake, watch out for any post op comp)
preparing patient for discharge:
ensure they are clean and comfortable
prepare meds
criteria for discharge
-sufficicently awake (able to sit, stand, respond to name)
-pain is controlled
-normal vital signs
-no evidence of post opp complication (hypothermia, hemmorrhage)
