Peri-op & Anaesthesia : Pre-op Assessment Flashcards
What is the purpose of the pre-op Assessment
- to identify pt co-morbidites that may lead to complications during the anaesthetic, surgical or post operative period
When does a pre-operative assessment happen?
Patients scheduled for elective procedures will generally attend a pre-operative assessment 2-4 weeks before the date of their surgery.
The Pre-op history - what is involved? (headings for now)
- History of the Presenting Complaint
- Past Medical History
- Past Surgical History
- Past Anaesthetic History
- Drug History
- Family History
- Social History
What would you ask about a pts Past medical hx in a pre-op assessment?
- CVD - including HTN
- Resp disease
- Renal disease
- Endocrine - Diabetes and Thyroid disease
- GORD - aspiration of gastric contents
- Pregnancy - all women of reproductive age will get a urinary test
- Sickle Cell disease - could be undiagnosed if country of birth does not have routine screening
Pre-op assessment: You are asking a pt about cardiovascular disease.
What are some good screening questions ?
- Exercise tolerance
good indicator of cardiovascular fitness ( for major surgery can predict risk of post-op complications / level of care)
Screening questions for undiagnosed disease:
* Exertional chest pain
* syncopal episodes
* orthopnoea
Pre-op assessment: You are asking a pt about their past medical history (respiratory disease.)
Why is adequate oxygenation and ventilation important?
Adequate oxygenation and ventilation is essential in reducing the risk of acute ischaemic events in the peri-operative period
Pre-op assessment: You are asking a pt about their past medical history (respiratory disease.)
What are some key questions to ask a pt how might this relate to anaesthetic choices?
Ask:
* can the patient lie flat for a prolonged period?
* do they have a chronic cough?
these are key as may preclude spinal anaesthesia
Screen for :
* symptoms and signs of obstructive sleep apnoea (if RF)
What to ask about a pts past surgical hx?
- Has the patient had any previous operations? If so, what, when, and why?
- If the patient is having a repeat procedure, this can significantly change both the surgical time and ease of operation, and hence influence the anaesthetic technique used
What to ask about a pts Past Anaesthetic History?
- Has the patient had anaesthesia before?
- If so, for what operation and what type of anaesthesia?
- Were there any problems?
- Did the patient experience any post-operative nausea and vomiting?
What to ask about a pts drug hx?
- A full drug history as some medications require stopping or altering prior to surgery.
- Ask about any known allergies, both drug and non-drug allergies
What to ask about Family history?
Most hereditary conditions relating to anaesthesia are extremely rare, (e.g. malignant hyperthermia), it is important to ask about any known family history of problems with anaesthesia
What to ask about Social history?
- smoking history, alcohol intake, and any recreational drug use
- Language spoken and the need for an interpreter
- Living situation, anyone at home (may need to stay overnight if no other adult at home), how they will get home etc. Work etc.
What does a pre-op examination involve
- GENERAL EXAMINATION- highlight any underlying undiagnosed pathology e.g. undiagnosed murmur or signs of HF, resp or GI symptoms.
* ASA score based on co-morbidities - AIRWAY EXAMINATION- to predict difficulty of airway management e.g. Mallampati score
AR the ASA score (American Society of Anaesthesiologists)
Pre-op Bloods: AR (reasons for later)
- FBC
- U&Es
- LFTs
- TFTS (condition specific)
- HBA1c (condition specific)
- Clotting screen
- G&S +/- cross matching
Why do FBC for a pre-op pt?
- Assess for any anaemia or thrombocytopenia, as this may require correction pre-operatively to reduce the risk of cardiovascular events or allow for preparation of blood products
Why do U&E’s pre-op?
- assess the baseline renal function
- help inform fluid management and drug decisions, both for anaesthesia and post-operative analgesia (e.g. morphine is generally avoided in those with CKD)
Why do LFTS pre-op?
- assessing liver metabolism and synthesising function
- useful for peri-operative management; if there is suspicion of liver impairment, LFTs may help direct medication choice and dosing
Why do a clotting screen?
Any indication of deranged coagulation such as”
* iatrogenic causes (e.g. warfarin)
* inherited coagulopathies (e.g. haemophilia A/B)
* liver impairment
will need identifying and correcting or managing appropriately in the peri-operative period
Compare Group and Save versus Cross-Match
What investigations might you order for a pt with a history of cardiovascular disease?
- ECG - show underlying pathology, baseline for comparison if post op concerns for cardiac ischaemia
- ECHO
- Myocardial perfusion scans (if untreated IHD or symptoms of angina- scans look for inducible ischaemia
When might you consider an ECHO for a pt in pre-op assessment (3 reasons)
if the person has :
* (1) a heart murmur
* (2) ECG changes
* (3) signs or symptoms of heart failure.
What Respiratory investigations might be done?
chronic lung conditions e.g. COPD / asthma
* spirometry for baseline
* refer for spirometry if S&S of undiagnosed pulmonary disease
* CXR not commonly performed
What are some other tests you might do pre-op?
- Urinalysis - UTI
- MSA swab from nostril and perineum for MRSA colonisation. Decontamination hair and body wash, along with topical ointment applied to the nostrils, will be given.
- Cardiopulmonary Exercise Testing (CPET). for high risk pts undergoing major surgery (graded intensity period on a stationary bicycle whilst wearing a mask, as well as ECG monitoring. It provides useful information, such as the VO2max and anaerobic threshold)
