GENERAL PRINCIPLES Flashcards
What are the components of a pre op assessment?
- Are they fit for surgery
- Haemostatic competence (are they going to bleed?)
- Coagulation screen: APTT, PT
- Group and save
What can cause a prolonged PT?
- Warfarin
- Vitamin K deficiency
- Liver disease
- Factor VII deficiency
-
What causes a prolonged APTT?
- Factor VIII deficiency (haem A)
- Factor IX deficiency (haem B)
What causes both a prolonged APTT and PT?
- DIC
- Massive transfusion
- Liver disease
- DOAC
What is the difference between primary, reactive and secondary bleeding?
Primary = Bleeding in intra-operative period
Reactive = Within 24 hours of op
Secondary = 7-10 days post op due to erosion of vessel from spreading infection
What are the clinical features of haemorrhagic shock?
- Tachycardia
- Dizziness
- Agitation
- Raised resp rate
- Hypotension is a late sign
What is the management of haemorrhagic shock?
- A to E
- IV access (18G cannula)
What steps of managment in haemorrhagic shock are there?
Read op notes - looking for sites of bleeding
Apply pressure to bleeding site
Urgent senior surgical review
Urgent blood tranfusion
What are the two types of delerium?
- Hypoactive (most common) - lethagy and reduced motor activity
- Hyperactive (most recognised) - agitation and increased motor activity
What are some risk factors for delerium?
> 65 years old
Co-morbidities
Underlying dementia
Renal impairment
What are some common causes for dementia?
- Hypoxia (post-op)
- Infection (UTI / LRTI)
- Drug withdrawal (alcohol)
- Dehydration/pain
- Contipation/urinary retention
How to assess a patient with delerium?
- Collateral history
- Onset and course of confusion
- Previous episodes
What scoring systems are there for delerium?
- Abbreviated mental test
- Mini mental state examination
- Confusional assessment method
Name some questions in the abbreviated mental test?
Age
Time (to nearest hour)
DOB
What is included in a confusion screen?
Bloods - FBC, U&Es, Calcium, TFTs, glucose
Blood cultures
Urinalysis/CXR
CT head
How should patients with delerium be managed?
Abx for infection, nasal oxygen if hypoxic, laxatives for constipation
- Nursed in quiet area with regular routine
- Oral haloperidol
What are some risk factors for post-op vomiting and nausea?
- Female
- Younger age
- Motion sickness
What areas in brainstem control vomiting?
Vomiting centre in the medulla oblongata
Chemoreceptor trigger zone (located outside BBB in 4th ventricle)
What are the neurotransmitters in each area of vomiting process?
CTZ: Dopamine (peripheral) and 5HT3 receptors
Vomiting centre: Histamine and 5HT3 receptors
(The CTZ acts on the vomiting centre)
What are the conservate treatments of PONV?
- Fluid hydration
- Analgesia
What should patients with PONV and impaired gastric emptying be given as an anti-emetic?
- Metoclopramide or domperidone (prokinetic, dopamine antagonists)
Other than pro-kinetics, what else can patients with PONV and bowel obstruction be given?
Hyoscine (anti-muscarinic) to help reduce secretions
What should patients with PONV and metabolic/biochemical imbalance e.g. uraemia be given?
Metoclopramide
What should patients with opiod-induced N&V be given?
Ondansetron (5HT3 receptor antagonist)
OR
Cyclizine (H1 Histamine receptor antagonist)
What are the steps in the WHO analgesic ladder?
- Simple analgesics (paracetamol/NSAIDs)
- Weak opiates (codeine or tramadol)
- Stronger optiates (morphine)
What can be used for neuropathic pain?
Amitriptyline / gabapentin
Name some NSAIDs, how do they work?
Ibuprofen/diclofenac - inhibit synthesis of prostaglandins - reducing potential inflammation
What are some side effects of NSAIDs?
I-GRAB
Interactions e.g. with warfarin
Gastric ulceration (consider PPI)
Renal inpairment (use sparingly here)
Asthma sensitivity
Bleeding risk (due to effect on platelets)
Name some strong opiates, how do they work?
Morphine, oxycodone, fentanyl
Activate opiod receptors
What are some side effects of opiates? How is this managed?
Constipation / nausea (laxatives and anti-emetics given concurrently)
Sedation, confusion, respiratory distress
Why should strong and weak opiates not be prescribed together?
Competitively inhibit the same receptor
What is patient controlled analgesia?
Name a pro and a con
Iv pumps which provide bolus of analgesia when button pressed
Pro - Tailored analgesia, risk of overdose negligible
Con - Cumbersome, not suitable for learning difficulties
What can cause post op fever?
Pneumonia, UTI, Surgical site infection, infected IV lines
How to source the infection in post op sepsis?
- Urine dip and culture
- Chest X-ray
- Surgical wound swabs
- LP
- Stool culture
What are the seven C’s for pyrexia in a surgical patient?
Chest (infection)
Cut (wound infection)
Catheter (UTI)
Collections (abdomen, pelvic etc.)
Calves (DVT)
Cannula (infection, if applicable)
Central line (infection, if applicable)
What does the term VTE encompass?
DVT and PE
What are the 3 points in Virchow’s triad?
- Abnormal blood flow (recent immobility)
- Abnormal blood components (smoking, sepsis, malinancy)
- Abnormal vessel wall (atheroma)
What are the risk factors for VTE?
- Age
- Previous VTE
- Smoking
- Pregnancy
- Recent surgery
How does a DVT present?
Unilateral leg pain and swelling
Pyrexia
Pitting oedema
What is the wells criteria?
Score greater than 1 indicates DVT
What is the treatment for a DVT?
DOAC e.g. apixaban, rivaroxaban (factor Xa inhibitors)
and dabigatran (direct thrombin inhibitor)
How does a PE present?
Sudden onset SOB
Pleuritic chest pain
Cough
Haemoptysis
What Well’s score indicates a PE?
Greater than 4
What are the 2 types of thromboprophylaxis?
Mechanical: Antiembolic stockings, intermittent penumatic conpression
Pharmacological: LMWH (unless poor renal function the UFH)
What are some common organisms in HAP>
E. Coli
S. Aureus (MRSA)
S. Pneumoniae
How would a GI anastomotic leak present?
Abdo pain and fever
How would an anastomotic leak be investigated?
CT scan with contrast
How is an anastomic leak treated?
NBM + broad spectum abx + surgery
What are some factors in the VTE risk assessment?
Cancer?
Age >60?
Dehydration?
Obesity?
Personal history of VTE?
What form part of the pre-op surgical checklist?
Confirmed identity?
Site marked?
Consented?
Allergies?
Risk of blood loss >500ml?
All team members introduced?
