Pre-op assessment Flashcards
Oral fluids/fasting requirements for surgery
May drink clear fluids until 2 hours before their operation
Purpose of drinking clear fluids before the operation
Can help reduce headaches, nausea and vomiting afterwards
How long must patients fast for prior to surgery
Generally advised to fast from non-clear liquids/food for at least 6 hours before surgery
Potential complications of poorly managed diabetes during surgery
Undetected hypoglycaemia whilst a patient is under GA
increased risk of wound and resp infections
Increased risk of post-op acute kidney injury
Increased length of hospital stay
Which grading system can be used to classify patients to indicate risk of absolute mortality
American Society of Anesthesiologists Grade (ASA)
What is Group and Save
Determines the patient’s blood group (ABO and RhD) and screens the blood for any atypical antibodies(takes around 40 mins)
Recommended if blood loss is not anticipated, but blood may be required if greater blood loss occurs
What is cross-match
Involves physically mixing the patient’s blood with donor’s blood, in order to see if any immune reaction takes place –> transfusion if not
Should be done pre-emptively if blood loss is anticipated
What happens if an MRSA sample is isolated from a patient prior to surgery
Decontamination hair and body wash, along with topical ointment applied to the nostrils, will be given
What might high-risk patients undergoing major surgery be referred for
Cardiopulmonary exercise testing(CPET)
What is CPET
Involves a graded intensity period on a stationary bicycle whilst wearing a mask, as well as ECG monitoring
Purpose of CPET
Provides VO2max and anaerobic threshold, which can be used to risk-stratify patients for post-op complications and need for higher level care environments
How long before surgery should a patient ideally have a pre-op assessment
2-4 weeks
What classification is used to assess the potential difficulty of a patient’s airway for intubation
Mallampati score stratifies the difficulty of endotracheal intubation based on anatomic features
Also Wilson’s score
Rules regarding use of antihypertensives and antiarrhythmics in patients undergoing surgery
ACE inhibitors should be withheld on the morning of major surgery
Beta-blockers should be continued as per prescription
Digoxin will need an ECG and blood tests to exclude hypokalaemia
Rules regarding use of antiplatelets in patients undergoing major surgery
Aspirin and NSAIDs can be continued
Clopidogrel causes irreversible platelet inhibition and therefore should be stopped 7 days before surgery and/or neuraxial intervention
How long before surgery should warfarin be stopped
Last dose of warfarin should be given 6 days before procedure
How long before surgery should heparin be stopped
Unfractionated heparin is short-acting and administered IV so must be stopped 4 hours before neuraxial block with evidence of a normal APTT
LMWH is longer acting and administered subcut so a neuraxial block cannot be performed for 12 hours following a prophylactic dose and 24 hours following a treatment dose
Oral hypoglycaemic agents in patients undergoing major surgery
Agents such as metformin should be omitted on the day of surgery
Use of hormonal therapies in patients undergoing surgery
OCP can increase risk of DVT so should be stopped
Why are antacids given prior to surgery
Ranitidine or omeprazole given to minimise stomach acid and reduce risk of aspiration during induction
Purpose of giving glycopyrrolate prior to surgery
Anti-sialogogue which reduces oral secretions prior to airway instrumentation
What are the three phases of an operation identified by the WHO checklist
1) Before the induction of anaesthesia (sign in)
2) Before the incision of the skin (time out)
3) Before the patient leaves the operating room (sign out)
Appropriate ix in IHD prior to surgery
Bloods
Urine
ECG
Treadmill/myocardial perfusion scan/angiography
Important blood parameter to check prior to thyroid surgery
Calcium
TSH
Anticoagulant to cover warfarin during surgery
Prophylactic tinzaparin
IV unfractionated heparin if mechanical heart valve
IX for respiratory disease patients prior to surgery
Peak Flow/FEV1 FVC/6 min walk
Peri-op - saline nebulisers, bronchodilators, chest physiotherapy, ABG
Important imaging ix prior to surgery for rheumatoid arthritis patients
Cervical x-ray - risk of Atlanta-axial subluxation
What is primary bleeding
bleeding that occurs within the intra-operative period
This should be resolved during the operation, with any major haemorrhages recorded in the operative notes and the patient monitored closely post-operatively
What is reactive bleeding
Occurs within 24 hrs of op
What are most reactive bleeding case slinked to
A ligature that slips or a missed vessel. These vessels are often missed intraoperatively due to intraoperative hypotension and vasoconstriction, meaning only once the blood pressure normalises post-operatively will this bleeding occur
What is secondary bleeding
occurs 7-10 days post-operatively
Secondary haemorrhage is often due to erosion of a vessel from a spreading infection.
Secondary haemorrhage is most often seen when a heavily contaminated wound is closed primarily
Which artery is vulnerable to laparoscopic ports
Inferior epigastric artery
Which artery is vulnerable during angiography
The puncture site is often the external iliac artery, above the inguinal ligament. Therefore, any bleeding from this artery will go into the retroperitoneum.
General mx of post op haemorrhage
Review operation notes Rapid fluid resus(18G minimum for IV) Direct pressure Urgent senior surgical review Urgent blood transfusion
Prep for theatre after senior review
Risk factors for post-op nausea and vomitng(PONV)
Female
Hx of pONV
Opioids
Non-smoker
Prophylactic measures for post-op nausea and vomiting
Anaesthetic measures – reduce opiates, reduce volatile gases, avoiding spinal anaesthetics
Prophylactic antiemetic therapy
Dexamethasone* at induction of anaesthesia
Conservative measures for post-op nausea and vomiting
Adequate fluid hydration
Adequate analgesia
Consider nasogastric tube insertion to aid gastric decompression
Pharmaceutical measures for post-op nausea and vomiting
Impaired gastric emptying or gastric stasis should be trialled on prokinetic agent(metoclopramide) unless bowel obstruction
Hyoscine to reduce secretions
Ondanstron or cyclising for opioid induced nausea and vomiting
What can nausea and vomiting after operation indicate
May be a sign of post-op complication such as ileum
Likely aetiology of pyrexia - day1-2 post op
consider a respiratory source (or body’s routine response to surgery)
Likely aetiology of pyrexia - day3-5 post op
consider a respiratory or urinary tract source
Likely aetiology of pyrexia - day5-7
Surgical site infection or abscess/collection formation
Other causes of pyrexia post op
Iatrogenic(drugs/transfusions)
VTE(low grade fever)
Prosthetic implantation
Causes of pyrexia of unknown origin
infection of unknown source (30%), malignancy (classically B-symptoms from lymphoma, 30%), connective tissue diseases or vasculitis (30%), or drug reactions
Mx of LRTI post op
Co-Amoxiclav 1.2g IV +/- Amikacin
Mx of UTI catheter associated
Co-Amoxiclav 1.2g IV +/- Amikacin
Nitrofurantoin 50mg PO + Change of Catheter
Mx of surgical site infection
Flucloxacillin 1g IV
Mx of central line infection
Replace line (trial antibiotic line lock with vancomycin if not able to replace line)
Interpretation of SOFA score
greater than or equal to two indicates sepsis; the SOFA score can also be used to monitor and quantify a patient’s clinical course and response to treatment for sepsis.
qSOFA criteria
Respiratory Rate ≥ 22/min (1 point)
Altered Mental State (1 point)
Systolic Blood Pressure ≤100mmHg (1 point)
Risk factors for anastomotic leak
Medication (such as corticosteroids and immunosuppressants)
Smoking or alcohol excess
Diabetes Mellitus
Obesity or malnutrition
Clinical features of anastomotic leak
Abdo pain and fever 5-7 days post op
Delirium
Prolonged ileus
Tachycardia
Signs of peritonism
IX for anastomotic leak
CT contrast of abdomen and pelvis
FBC/CRP/U&Es/LFTs and clotting screen
VBG
Repeat group and save
Initial mx of anastomotic leak
A-E
NBM
Broad spectrum ABX
IV fluids and urinary catheter
Definitive mx of anastomotic leak
Collections <5cm managed conservatively
Larger ones drained percutaneously
Exploratory laparotomy if septic or multiple collections
Risk factors for post-op ileus
Increased age
Electrolyte derangement (e.g. Na+, K+ and Ca2+ derangement)
Neurological disorders (e.g. Dementia or Parkinson’s Disease)
Use of anti-cholinergic medication
Surgical factors which increase risk of post-op ileum
Use of opioid medication
Pelvic surgery
Extensive intra-operative intestinal handling
Peritoneal contamination (by free pus or faeces)
Intestinal resection
Clinical features of post-op ileus
Failure to pass flatus or faeces
Sensation of bloating and distention
Nausea and vomiting (or high NG output)
Abdominal distension and absent bowel sounds
Ix for post-op ileus
FBC and CRP
U&Es
Electrolytes
CT abdo and pelvis
Mx of post-op ileus
NBM
Daily bloods to monitor AKI
Encourage mobilisation
Reduce opiate analgesia
Prophylactic measures for post-op ileus
Minimise intra-operative intestinal handling
Avoid fluid overload (causing intestinal oedema)
Minimise opiate use
Encourage early mobilisation
What are adhesions
fibrous bands of scar tissue. Many occur secondary to previous surgery or intra-abdominal inflammation (particularly pelvic)*, however they can also be congenital.
Common cause of SBO
Clinical features of bowel adhesions
Asymptomatic
Obstruction
Infertility
Chronic pelvic pain
Mx of bowel adhesions
Conservative mx with tube decompression
NBM
IV fluids
Adequate analgesia
Surgical mx of bowel adhesions
Adhesiolysis Laparoscopic mx(mainstay)
Risk factors for incisional hernia
Emergency surgery BMI > 25 Midline incision Post-op wound infection DM Steroids Age Smoking
Clinical features of incisional hernia
reducible, soft and non-tender swelling at or near the site of a previous surgical wound. If the hernia is incarcerated, it can become painful, tender, and erythematous.
Mx of incisional hernia
Suture repair for small hernias
Laparoscopic mesh repair/open mesh repair
Abdominal wall reconstruction
Iatrogenic causes of post-op constipation
medications such as opioid analgesia, anticonvulsants, iron supplements, or antihistamines
