peri op (general) Flashcards
When you have an acute surgical admission how do you manage/stabalise the patient?
Sytem of five
- Investigations
- Bedside obs
- Microbiology: samples sent for culture (e.g. wound swabs, urine or blood cultures). All acute admissions should be screened for MRSA. Elective patients who are MRSA positive and have not received decontamination treatment should not be taken to theatre (unless they need emergency surgery)
- Blood tests: baseline blood tests: FBC, U&Es, LFTs, Amylase, and a Clotting profile. G&S (significant operation) + specialist blood tests that may be required
- Imaging e.g. ECG or CXR -> baseline health
- Specialist tests e.g. CT imaging or endoscopy
- Explain the system of five for management of the acute surgical admission
- The Multidisciplinary Team
Major surgery is a significant physiological insult to the body, real risk of functional decline in the post-operative period, and anticipatory therapy may be required.
To address this, the involvement of a MDT is often needed. This can occur pre-operatively, in order to optimise the patient and to anticipate any decline, or post-operatively if the decline was not anticipated. MDT members commonly include:
- VTE prophylaxis
+ LMWH for pre- and post-op prophylaxis of VTE (extended course of prophylaxis is usually required in patients undergoing surgery for malignancy or in those who have had orthopaedic surgery involving the lower limbs)
+ TED stockings prescribed (as long as no history of arterial disease)
- Start a Drug Chart, consider:
Analgesia
Anti-emetics
Antimicrobials
Any normal regular medications
- IV access and consider Inputs and Outputs (When taking blood tests, place an IV cannula at the same time)
+ NBM?
+ Fluids prescribed?
+ vommiting -> NG tube?
+ urinary catheter
- Oxygen
+ 94-98% in most patients, or 88-92% in known CO2 retainers (e.g. patients with COPD)
- Senior Referral & Involvement of the MDT
2. Physiotherapy (PT)
Occupational therapy (OT)
Speech & language therapy (SALT)
There is also an important role for dieticians in helping to manage the perioperative patient. Where patients are malnourished pre-operatively, dieticians can address this, in an attempt to reduce the patient’s risk of perioperative complications. Post-operatively, if a patient is NBM for any significant period of time (usually ~5 days or so), dieticians can organise suitable dietary supplementation.
- Haemorrhage in the surgical patient can be classified into 3 main categories:
- What is the most sensitive sign for haemorrhagic shock?
- Explain how you grade shock
1.
- Primary bleeding – bleeding that occurs within the intra-op period
This should be resolved during the operation, with any major haemorrhages recorded in the operative notes and the patient monitored closely post-operatively
- Reactive bleeding – occurs within 24hrs of operation
Most cases of reactive haemorrhage are from 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
- Secondary bleeding – occurs 7-10 days post-operatively
~ erosion of a vessel from a spreading infection, most often seen when a heavily contaminated wound is closed primarily
- Raised respiratory rate,
Hypotension is usually a late sign
- Post-operative thyroidectomy or parathyroidectomy haemorrhage can have catastrophic consequence, how?
- What artery is vulnerable to injury from laparoscopic ports or the Pfannenstiel incision?
- airway obstruction, the pretracheal fascia of the neck will only distend so far; when bleeding occurs into this space, compression on the venous return results in venous congestion, with subsequent laryngeal oedema leading to eventual asphyxiation
- inferior epigastric artery (arises from the external iliac artery)
Sepsis
- Investigations and management
- Identification of the infection source is important in the investigation of sepsis cases. Appropriate investigations may include:
- Whilst many septic patients can be managed in the ward environment with early senior support, involvement of intensive care / clinical outreach teams should be considered when:
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Further management may include assessment by intensive care teams and commencing vasopressor agents (e.g. noradrenaline), renal replacement therapy, and/or ventilator support.
- Urine dip +/- culture
Chest X-ray (CXR)
Swabs (e.g. surgical wounds)
Operative site assessment (via CT or US imaging)
Cerebrospinal fluid sample (via LP)
Stool culture
3.
- Evidence of septic shock
- Lactate > 4.0mmol
- Failure to improve from initial management
The common sources of pyrexia in a surgical patient can be remembered using the seven C’s:
- Post-operative pain can be assessed subjectively and objectively:
- Conseqeunces of poor pain control?
- Explain the WHO pain ladder
Subjective – Ask the patient to grade their pain
Objective – Clinical features of pain include tachycardia, tachypnoea, hypertension, sweating, or flushing
An unwillingness to mobilise or agitation may be present in those that are less able to communicate their pain.
Each patient should be assessed when mobile, when taking a deep breath, and when in bed (a pain-free patient in bed may well be in severe pain when they walk to the toilet!).
- Slower recovery -> reluctant to mobilise -> slower restoration of function and rehabilitation capacity
Abdominal surgery -> inadequate ventilation -> HAP
- Non-opioid analgesia e.g. paracetamol, NSAIDs (e.g ibuprofen or diclofenac).
NSAIDs work by inhibiting the synthesis of prostaglandins, thereby reducing the potential inflammatory response causing the pain.
Used in musculoskeletal conditions. They are also frequently used intraoperatively.
The side effects of NSAIDs include (a useful mnemonic is I-GRAB):
How long does it take morphine to work IV, orally and IM
- Opiate Analgesics
Opiates are divided into weak opiates, such as ?, or strong opiates, such as ?
They work by activating opioid receptors ?, distributed throughout the CNS.
Side effects:?
1.
- Interactions with other medications (e.g. Warfarin)
- Gastric ulceration (consider adding a PPI when prescribing NSAIDs long-term)
- Renal impairment
- Asthma sensitivity (triggers 10% of individuals with asthma)
- Bleeding risk (due to their effect on platelet function
- codeine,
morphine, oxycodone or fentanyl
MOP, DOP, and KOP
- Constipation (laxative: lactulose)
- Nausea (anti-emetics: meto-clopramide)
- Sedation and confusion
- Respiratory depression
- Pruritus
- What is patient controlled analgesia? adv and disadv
- Describe neuropathic pain. Plus, the managment available.
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- shooting or stabbing pains
Following surgery, the prevalence of neuropathic pain is as high as 10%. ~ orthopaedic or vascular surgery, particularly in amputees (due to the nerve damage sustained when the limb is severed).
- Non-pharmacological treatment – CBT, transcutaneous electric nerve stimulation (TENS), or capsaicin cream (typically for localised pain).
- Pharmacological therapies – gabapentin, amitriptyline, or pregabalin.
Post-op N+V
- Consequences of PONV:
- There are a number of risk factors for PONV. They can be divided into patient factors, surgical factors, and anaesthetic factors:
- There are two areas in the brainstem that play a key role in the control of N+V:
- increased anxiety for future surgical procedures
increased recovery time and hospital stay,
severe cases - aspiration pneumonia, incisional hernia or suture dehiscence, bleeding, oesophageal rupture, and metabolic alkalosis.
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- Vomiting centre – located within the lateral reticular formation of the medulla oblongata. It controls and coordinates the movements involved in vomiting.
Chemoreceptor trigger zone – located in the area postrema (situated at the inferoposterior aspect of the 4th ventricle). It is located outside the blood brain barrier and can therefore respond to stimuli in the circulation.
- The vomiting centre receives input from the:
- If the stimuli are sufficient, it acts on the
- A number of neurotransmitters are involved in the control of vomiting. This is important clinically, as they can be targeted by anti-emetic medications. A summary of the neurotransmitters in the vomiting process:
- In addition, it is important to be aware of alternative causes of nausea and vomiting in the post-operative patient, such as?
1.
- chemoreceptor trigger zone,
- GI tract,
- Vestibular system
- Higher cortical structures (such as sight, smell and pain)
- Diaphragm, stomach and abdominal musculature to initiate vomiting
3.
- Chemoreceptor trigger zone: Dopamine and 5HT3 receptors
- Vestibular apparatus: Acetylcholine and Histamine receptors
- GI tract: Dopamine receptors
- Vomiting centre: Histamine and 5HT3 receptors
- Infection
GI causes (post-operative ileus, bowel obstruction)
Metabolic causes (hypercalcaemia, uraemia, DKA)
Medication (antibiotics, opioids)
CNS causes (raised ICP)
Psychiatric causes (anxiety)
The management of post-operative nausea and vomiting can be divided into three areas; prophylactic, conservative and pharmaceutical.
Prophylactic Measures
- Anaesthetic measures – reduce opiates, reduce volatile gases, avoiding spinal anaesthetics
- Prophylactic antiemetic therapy
- Dexamethasone* at induction of anaesthesia
*8mg dexamethasone significantly reduces the incidence of PONV at 24 hours and the need for rescue antiemetics for up to 72 hours in patients following large and small bowel surge
Conservative Measures
- Adequate fluid hydration
- Adequate analgesia
- Ensure no obstructive cause
Pharmaceutical Measures
- Impaired gastric emptying or gastric stasis: should be trailed on a prokinetic agent, such as metoclopramide (dopamine antagonist) or domperidone (dopamine antagonist), unless bowel obstruction is suspected
Bowel obstruction: Hyoscine (an anti-muscarinic) can help to reduce secretions
- A suspected metabolic or biochemical imbalance, such as uraemia, electrolyte imbalance, or cytotoxic agents: metoclopramide
- Opioid-induced: ondansetron (5-HT3 receptor antagonist) or cyclizine (H1 Histamine receptor antagonist)
well-hydrated, any pain is well controlled, and anxiety is treated appropriately.
Postop pyrexia
- Aetiology:
- Other causes of post-op pyrexia include:
- Clinical features?
- Investigations
- Management
- Infection
- Day 1-2 – consider a respiratory source
- Day 3-5 – consider a urinary tract source
- Day 5-7 – consider a surgical site infection or abscess/collection formation
- Any day post-operatively – consider infected IV lines or central lines as a sources
2.
- Iatrogenic – which may include a drug-induced reaction (e.g. antibiotics or anaesthetic agents) or from a transfusion reaction.
- VTE – although rare, a PE or DVT can cause a low grade fever without any other overt clinical features
- Secondary to prosthetic implantation – with any foreign body, for example after an AAA repair, a low-grade fever may be evident
- Pyrexia of Unknown Origin: recurrent fever >38C persisting for >3wks without an obvious cause despite 1wk inpatient investigation
Causes of PUO: infection of unknown source 30%, malignancy, CT disease/vasculitis
3.
- A-E approach
- Enquire about specific systems symptoms: urinary frequency, urgency, or dysuria, productive cough or dyspnoea, haemoptysis, chest or calf pain, or wound or IV line tenderness or discharge.
- O/e: examine for signs of pulmonary infection, IV line infections, wound infections, and calf tenderness. If post-operative, also examine for specific complications from the operation (e.g. signs of peritonism in anastomotic leak).
4.
A septic screen is essential in investigating the surgical patient with pyrexia. In most cases, the source is obvious and your screen can be tailored accordingly, yet in a less clear presentation a wider screen is indicated. It can include:
- Blood tests– FBC, CRP, U&Es.
- Urine dipstick
- Cultures– blood, urine, sputum, and wound swab
- Imaging– Chest X-ray
If the source cannot be identified through the septic screen, more detailed investigations may be required, such as a CT scan -> anastomotic leak or Doppler US -> DVT.
State the empirical Abx used for the infection source
Postop delirium
- There are 3 main types of delirium:
- RF:
- Causes:
- How to assess delirium?
DELIRIOUS DICE
1.
- Hypoactive delirium (most common) – marked by lethargy and reduced motor activity
- Hyperactive delirium (most recognised) – marked by agitation and increased motor activity
- Mixed agitation – marked by fluctuations throughout a day
- Age >65yrs, Multiple co-morbidities, Underlying dementia, Renal impairment, Male gender, Sensory impairment (hearing or visual)
3.
- Hypoxia (post-operatively)
- Infection (commonly UTI or LRTI)
- Drug-induced (benzodiazepines, diuretics, opioids, or steroids) or drug withdrawal(alcohol or BZNs)
- Dehydration or pain
- Constipation or urinary retention
- Endocrine abnormalities (e.g. hyponatraemia, hypernatraemia, or hypercalcaemia)
DICE
- Collateral history from family members or nursing staff will normally provide key information. The key features to ascertain include:
- Onset and course of confusion
- Symptoms of a possible underlying cause
- Co-morbidities and previous baseline cognition
- Previous episodes
- Drug history (including alcohol intake)
- Abbreviated Mental Test (AMT)
- Mini-Mental State Examination (MMSE)
- A Confusional Assessment Method (CAM)
- Review their obs, drug chart, look for any signs of infection (including any surgical site infections) or pain, and check for signs of constipation or urinary retention
- neurological examination should be performed to rule out any sinister underlying neurological pathology (e.g. stroke or subdural haematoma).
Explain the 4AT test
Explain the AMT10
