20 - Perioperative Care Flashcards
What is the pre-operative assessment?
Done a few weeks before surgery to identify any co-morbidities than may lead to complications during anaesthetic, surgery or the post-operative period
- History
- Full general examination (cardio, resp, abdo)
- Investigations
- Anaesthetic airway review
How do you take a preop history?
- History of presenting complaint
- PMH
- Past surgical history
- Past anaesthetic history (any post op N+V?)
- DHx
- FHx (malignant hyperthermia which is autosomal dominant)
- SHx (alcohol, smoking, exercise tolerance)
What are the different ASA grades?
I - Normal healthy
II - Mild systemic disease inc smoking
III - Severe systemic disease
IV - Severe systemic illness that is constant threat to life
V - Not expected to survive without operation
What are some preoperative investigations that may be done?
https://www.nice.org.uk/guidance/ng45/chapter/recommendations#chest-xray
https://www.nice.org.uk/guidance/ng45/resources/colour-poster-2423836189
- Blood tests (see image)
- ECG (if history of cardiovascular disease)
- Pregnancy test
- Urinalysis
- MRSA swabs
What is the difference between a group and save and a cross match?
G+S
- Determines blood group and antibodies (ABO and RhD)
- No blood issued
- Not anticipating blood loss
Cross Match
- Mixing patient’s blood with donors blood to see if there is an immune reaction
- Blood is issued
- Done after a G+S
- If anticipating blood loss
What is the airway examination done preoperatively?
- Look at face for any obvious abnormalities (e.g receding mandible retrognathia)
- Open mouth and look for:
- Degree of mouth opening
- Any false teeth? Any loose teeth? Dental hygiene?
- Mallampati classification of oropharynx when maximally protruding tongue
- Assess neck movements and ask to extend, if distance between thyroid cartilage and chin is less than 6.5cm (three finger breadths), intubation may be difficult
What are some drugs that need to be stopped, started or altered before surgery?
STOP (CHOW)
- Clopidogrel 7 days before
- Hypoglycaemics
- COCP or HRT 4 weeks before
- Warfarin 5 days before (needs to be <1.5 before surgery)
ALTER
- Subcut insulin to IVI
- Long term steroids need to be continued due to risk of Addinsonian crisis, if cannot take orally switch to IV (5mg PO Prednisolone = 20mg IV hydrocortisone)
START
- LMWH
- TED stockings
- Antibiotic prophylaxis
What patients need LMWH for 28 days and TED stockings for this period too after surgery?
- Major GI surgery for cancers
- Lower limb joint replacements
How is a type I diabetics insulin managed during an operation?
PUT FIRST ON THE LIST
- Night before surgery reduce s/c basal insulin dose by 1/3rd
- Omit morning insulin and start IVVRI (continue any s/c long acting insulin)
- Start 5% dextrose at 125 ml/hr
- Take BM every 2 hours
- Keep giving IVVRI until can eat and drink and overlap 30-60 mins with s/c insulin
How are type II diabetics managed before surgery with their anti-diabetic drugs?
- If diabetes is diet controlled no change
- If on medication stop oral hypoglycaemics 24 hours before and stop metformin morning of surgery
- IVVRI with 5% dextrose then given
When is bowel preparation needed?
Why does a septic patient need large volumes of IV fluid to maintain their intravascular volume?
Tight junctions between capillary endothelial cells break down and cells become more permeable
Increased hydrostatic pressure and reduced oncotic pressure means more fluid leaves the blood vessels
What are some fluid inputs and outputs?
What are the two things checked for on a cross match and who is a universal donor and acceptor?
Rhesus D (most patients are positive) and ABO
Universal Donor: O -ve
Universal Acceptor: AB +ve
When do patients need to be given CMV -ve blood and irradiated blood products?
CMV -VE: Pregnant women and neonates up to 28 days as CMV has risk of sensorineural deafness and cerebal palsy
Irradiated: (treated with radiation) reduces risk of graft v host disease, see image
How are patients given a blood transfusion?
- Green (18G) or Grey (16G) cannula as otherwise cells haemolyse as tube too narrow
- Take observations before transfusion, 15-20 minutes after starting, 1 hour after starting and on completion
What do the following blood products contain and what are they used for:
- Packed Red Cells
- Platelets
- Fresh Frozen Plasma (FFP)
- Cryoprecipitate
Packed red cells:
- Contain RBC
- Used for acute blood loss or chronic anaemia where Hb<70 or symptomatic. 1 unit should raise Hb by 10
- Given over 2-4 hours
Platelets
- Contain platelets
- Used for haemorraghic shock, thrombocytopaenia, bleeding with thrombocytopenia, preoperative platelets <50. Should raise platelets by 20-40
- Given over 30 minutes
FFP
- Contains clotting factors
- Used for DIC, haemorraghe due to liver disease, massive haemorraghe after two units of PRC
- Given over 30 minutes
Cryoprecipitate
- Contains fibrinogen, vWF, factor VIII and fibronectin
- Used for DIC with low fibrinogen, vW disease, massive haemorraghe
What is the Enhanced Recovery After Surgery (ERAS) protocol?
Pre-operative
- Educate patients about surgery and milestones/post-op complications after
- Ensure patient as healthy as possible (stop weight loss, smoking, lost weight)
- Optimal preoperative fasting
Intraoperative
- Use of multimodal and non-opioid analgesia
- Use of multimodal post op nausea and vomiting prophylaxis
- Minimally invasive surgery
Postoperative
- Adequate pain control
- Early oral intake
- MDT post-op patient follow up
What is the point of the ERAS protocol?
Reduces post-operative complications, length of hospital stay and overall costs
What procedures are considered for day case surgery and what are the advantages of day case?
Considered if:
- Minimal blood loss expected
Day case surgery is the admission of select patients to hospital for a planned surgical procedure, returning home on the same day. In the UK, this represents about 70% of all surgery performed.
- Short duration <1hr
- No expected intra/post-op complications
- No specialist aftercare needed
- Social and medical factors acceptable
Advantage:
- Shorter inpatient stay
- Lower infection rates
- Reduced waiting lists
- Cheaper
How can you classify the different types of haemorraghe in a surgical patient?
- Primary: intraoperatively
- Reactive: within 24 hours of operation, usually due to a missed vessel or ligature that slips, don’t usually see intraoperatively due to intraoperative hypotension
Secondary: occurs 7-10 days post operatively, usually due to erosion of a vessel from a spreading infection
What are some clinical features of haemorraghic shock post-operatively and how can you classify this type of shock?
- Raised respiratory rate (most sensitive)
- Tachycardia
- Dizziness
- Agitation
- Decreased urine output
- Hypotension is late sign
Look for any peritonism, swelling and discolouration on examination
How do you manage post-operative bleeding?
- A to E with 18G cannula minimum and fluid resus
- Read the operation notes to look for wounds, drains, type of surgery
- If bleeding visible apply direct pressure
- Urgent senior surgical review to see if need reoperation
- Urgent blood transfusion with PRC, FFP, platelets and major haemorraghe protocol
What are some signs of post-operative bleeding in the following cases:
- Neck surgery (e.g thyroid/parathyroidectomy)
- Inferior Epigastric Artery Injury
- Retroperitoneal bleeding post angiography
Neck: Airway obstruction as pretracheal fascia can only extend so far. need to airway rescue by removing skin clips and deep suture layers and suction haematoma below
Inferior Epigastric Artery Injury: comes from external iliac and can be damaged by laparoscopic ports as runs along rectus muscle mid-clavicular line
Retroperitoneal Bleeding Post Angiography: puncture site for this procedure is usually external iliac so any bleeding will go into retroperitoneum. if suspected apply direct pressure to puncture site, resuscitate, give blood products
What is sepsis?
Sepsis is life-threatening organ dysfunction due to abnormal/uncontrolled host response to an infection
- Presence or suspected infection
- Clinical features of organ dysfunction
What is the SOFA and qSOFA score?
SOFA
- Helps to quantify the level of organ dysfunction if patient has infection
If 2 or more then indicates sepsis
qSOFA
- Shortened version of SOFA score purely on clinical signs
- If patient has signs of infection and a qSOFA of 2 or more then investigate and manage for sepsis
What is the sepsis 6?
DON’T FORGET BLOOD CULTURES
- Hourly observations
- Involve seniors early
- Ask ICU if need vasopressors, renal replacement and/or ventilator support
What are some investigations done for source identification of sepsis?
- Urine dip +/- culture
- CXR
- Swabs e.g surgical wounds
- Operative site assessment (CT or US)
- CSF sample from LP
- Stool culture
When should you escalate care of a septic patient to ITU or outreach?
- Evidence of septic shock
- Lactate >4.0 mmol
- Failure to improve from initial management
What are the causes of pyrexia in a surgical patient?
7 C’s
What is the definition of septic shock?
Sepsis with hypotension desire adequate fluid resuscitation or needing inotropes to maintain a normal systolic b.p
Need ITU input
What should you offer for acute pain relief in surgical patients?
- Start with simple analgesics e.g paracetamol and NSAIDs
- If not working use weak opioids e.g codeine and tramadol
- After a few hours if still not working consider morphine
How long does morphine take to work through different administration routes?
If using opiates always prescribe regular concurrent paracetamol to reduce opiate requirement
Don’t use combinations of weak and strong opiates
2-3 minutes IV, 20 minutes orally, 15 minutes IM
What is some pharmacological and non-pharmacological treatment for post-operative neuropathic pain?
Often following orthopaedics or vascular surgery
Due to irritation or injury directly to nerves both centrally and peripherally
What are the consequences of post operative nausea and vomiting?
- Increased recovery time and hospital stay
- Aspiration pneumonia
- Incisional hernia
- Suture dehiscence
- Bleeding
- Oesophageal rupture
- Metabolic alkalosis
What are some risk factors that increase a patient’s chance of post-operative N+V?
Patient Factors: female, young age, previous PONV, motion sickness, opioid analgesics, non-smoker
Surgical Factors: intrabdominal laparoscopic surgery, intracranial or middle ear surgery, squint surgery, gynae surgery, prolonger operative times, poor pain control post-op
Anaesthetic Factors: opiate analgesia or spinal anaesthesia, inhalational agents, prolonged anaesthetic time, intraoperative dehydration, overuse of BVM ventilation as gastric dilatation
What is the pathophysiology of vomiting?
- Vomiting centre: in medulla oblongata
- Chemoreceptor Trigger Zone: outside BBB near 4th ventricle so can respond to chemicals in the blood
How do you assess a patient with PONV?
- Are they drowsy? If so risk of aspiration so consider NG tube
- What was the operation? Is it likely to cause PONV?
- Which anaesthetic agents/drugs used?
- What antiemetic therapy would be best?
What are the prophylactic measures put in place to avoid PONV?
- Anaesthetic measures: reduce opiates, reduce volatile gases, avoid spinal anaesthesia
- Prophylactic antiemetic therapy
- Dexamethasone at induction of surgery
What could PONV indicate in a surgical patient?
Could be sign of post-op complication like:
- Ileus
- Bleeding
What are some different pharmacological options for anti-emetic therapy in PONV?
Often used in combination
Impaired gastric emptying or stasis: use pro-kinetics like domperidone (dopamine antagonist) or metoclopramide (dopamine antagonist) as long as no bowel obstruction
Bowel obstruction: hyoscine hydrobromide (antimuscarinic) can reduce secretions and therefore N+V
Metabolic/Biochemical Imbalance: metoclopramide
Opioid Induced PONV: ondansetron (5HT3 antagonist) or cyclizine (H1 antagonist) (not in children or elderly women)
What is the common aetiology of post-operative pyrexia at different days after surgery?
Common in surgical patients due to underlying disease process or as post op complication. USUALLY DUE TO INFECTION
Day 1-2: respiratory source
Day 3-5: urinary tract source
Day 5-7: surgical site infection or abscess formation
Any day: infected IVs or central lines
Can remember- Surfing on a WAVE, WIND blows you off, end up in WATER, have to WALK to shore, get cut so end up with WOUND, sit on the beach and WONDER
What are some other causes of post-operative pyrexia that are not due to infection?
- Iatrogenic: drug-induced reaction (e.g abx or anaesthetic agents) or transfusion reaction
- VTE: DVT or PE will cause low grade fever
- Secondary to prosthetic implantion: any foreign body
- Pyrexia of unknown origin
What is pyrexia of unknown origin?
Recurrent fever (>38 degrees) persisting for >3 weeks without an obvious cause despite 1 week of inpatient investigation
- Infection of unknown source
- Malignancy (B symptoms from lymphoma)
- Connective tissue diseases
- Vasculitis
- Drug reactions
How is post-operative pyrexia managed?
- Start empirical abx if infection (see image)
- Increase observations
- Start fluid balance and keep patient hydrated
What is delirium and what are the three types?
Delirium is an acute confusional state with disturbed consciousness and reduced cognitive function
Occurs in around 15% of elderly patients after surgery
What are the differences between delirium and dementia?
What are some risk factors for delirium?
- >65 years
- Multiple co-morbidities
- Underlying dementia
- Renal impairment
- Male gender
- Sensory (hearing or visual) impairment
What are some common causes of delirium?
- Hypoxia (post-operatively)
- Infection (UTI and LRTI)
- Drug induced (benzos, diuretics, opioids, steroids) or drug withdrawal (alcohol and benzos)
- Dehydration
- Pain
- Constipation or urinary retention
- Electrolyte abnormalities
What is the confusion assessment method (CAM)?
Tool for identifying delirium
How do you assess an acutely confused post-operative patient?
Often need collateral history from relative or nurses to find out:
- Onset and course of confusion?
- Symptoms of possible underlying cause?
- Comorbidities and baseline cognition?
- Previous episodes?
- Drug history (inc alcohol)
Do an AMT or MMSE or CAM, neuological examination to rule out sinister pathology and review drugs and observations
What is a confusion screen?
Done for any post-operative patient with confusion
What is the pathophysiology of atelectasis post-operatively?
- Due to a combination of airway compression, alveolar gas resorption intraoperatively and impairment of surfactant production
- Due to reduced airway expansion there is an accumulation of pulmonary secretions so patients at risk of pulmonary complications e.g hypoxaemia, reduced lung compliance, pulmonary infections, acute respiratory failure
What are some risk factors for developing atelectasis after surgery?
- Age
- Smoking
- General anaesthesia
- Duration of surgery
- Pre-existing lung or neuromuscular disease
- Prolonged bed res
- Poor post op pain control (shallow breathing)
How will a surgical patient with atelectasis present?
- Increased resp rate
- Reduced oxygen saturations
- Fine crackles
- Low grade fever
How do you diagnose and manage post-operative atelectasis?
Dx
- Often clinical diagnosis especially if pt has respiratory symptoms within 24 hours of surgery
- CXR and possible CT if x-ray inconclusive
Mx
- Deep breathing exercise and chest physio
- Adequate pain control
- Last resort if others dont work is bronchoscopy to suction out secretions
What is the definition of pneumonia?
Lower respiratory infection with consolidation visible on x-ray
Why are surgical patients predisposed to developing lower respiratory tract infections?
- Reduced chest ventilation: especially if bedridden, leads to accumulation of fluid secretions which can get infected
- Change in commensals: hospital has E.Coli, MRSA, S.Pneumoniae, Pseudomonas
- Debilitation from surgery
- Intubation
- Ventilators
What are some risk factors for developing hospital acquired pneumonia?
What are the clinical features of pneumonia?
- Cough
- Dyspnea
- Chest pain
- Increased RR, HR and temp
- Reduced O2 sats
- Pyrexial
- Bronchial breath sounds and inspiratory crackles
- Dull percussion note
How is HAP managed and how can it be prevented?
- O2 therapy to keep sats above 94%
- Once confirmed use empirical abx (see image)
- Prevent with chest physiotherapy if long bed rest or reduced mobility
What are some complications of pneumonia?
- Pleural effusion
- Empyema
- Respiratory failure
- Sepsis
How is aspiration pneumonia managed?
- Mainly preventative by getting Speech and Language involved
- If pneumonitis just supportive treatment
- If pneumonia then abx therapy similar to HAP
What is the definition of ARDS?
Severe hypoxemia in the absence of a cardiogenic cause.
Occurs when there is inflammatory damage to the alveoli, which leads to pulmonary oedema, respiratory compromise and acute respiratory failure
What are some direct and indirect causes of ARDS?
What is the pathophysiology of ARDS?
1. Exudative Phase: diffuse alveolar damage due to initial tissue injury. Cytokines and inflammatory mediators are released causing alveolar and endothelial injury
2. Proliferative Phase: restoration of alveolar capillary membrane integrity by fibroblasts and type 2 pneumoncytes, new surfactant is made
3. Fibrotic Phase: fibrin deposition across the lungs causing scarring, leads to need for long term oxygen
What are some investigations done when ARDS is suspected?
- ABG
- Routine bloods (FBC, U+Es, amylase, CRP)
- CXR (shows bilateral infiltrates)
- ECG (rule out cardiogenic cause)
What are the management principles of ARDS?
- Supportive treatment with ventilation
- Focused treatment of the underlying cause
All treatment done to limit inflammatory cascade and therefore reduce alveolar injury
What are some risk factors for a surgical site infection?
- Patient factors
- Operation factors
How does a surgical site infection present?
Usually 5-7 days post op but can occur up to 3 weeks later
- Spreading erythema
- Localised pain
- Pus or discharge from the wound
- Wound dehiscence
- Persistent pyrexia
How are surgical site infections investigated and managed?
Ix
- Wound swab and culture, avoiding wound edges due to skin flora
- Blood tests for infection markers (FBC and CRP)
- Blood cultures if systemic involvement
Mx
- Remove any sutures or clips to allow pus to drain
- Empirical abx based on local guidelines
How are surgical site infections prevented?
Preoperatively
- Prophylactic abx if indicated
- Do not routinely remove hair, if have to do immediately before surgery
- Advice patient to shower before surgery, optimal nutrition, weight loss, diabetic control
Intraoperatively
- Prepare skin before incision with antiseptic either povidone-iodine or chlorhexidine
- Change gloves or gown if contaminated
- Interactive dressing at the end of the operation to cover all incisions
Postoperatively
- Monitor wounds closely and use see through dressings to prevent having to change a lot
- Ensure that wounds in difficult areas e.g groin are closely monitored
- Refer to tissue viability nurse if secondary intention healing occuring
- Topical abx
What are the clinical features of a patient with an anastomotic leak?
- Abdominal pain
- Fear
- Delirium
- Prolong ileus
- May be pyrexial, tachycardia and peritonitic on examination
Uusally 5-7 days post-op. Any patient with GI surgery not progressing or sepsis consider anastomotic leak
How do you manage an anastomotic leak?
URGENT SENIOR REVIEW
Initially: Make patient NBM, start broad spectrum abx, start IV fluids, insert urinary catheter for fluid balance
Definitive: If minor <5cm collection usually IV abx, if larger need percutaneous drainage if possible. If septic exploratory laparotomy with extensive wash out and large drain insertion
Consider parenteral nutrition as may need to be NBM for long time
What are some risk factors for post-operative ileus?
Common in abdominal surgery and pelvic orthopaedic surgery
How does post-op ileus present?
Similar to bowel obstruction as technically functional bowel obstruction
- Failure to pass flatus or faeces
- Bloating or distension
- Nausea and vomiting
- Absent bowel sounds (not tinkling like mechanical)
What is the definition of post-operative ileus and how is it investigated if suspected?
Deceleration or arrest in intestinal motility following surgery
- Routine bloods (FBC, CRP, U+Es, Ca, PO4, Mg)
- CT scan abdo/pelvis with contrast to rule out anastomotic leaks and collections
How is post-op ileus managed?
- NBM
- IV fluids and fluid balance chart
- Daily bloods inc electroltes to check for AKI as can cause third space losses
- Encourage mobilisation
- Reduce opiates
WARN PATIENT FIRST FEW STOOLS MAY BE WATERY AFTER ILEUS
What are some prophylactic measures taken to prevent post-op ileus?
What are some complications of adhesions from surgery?
- Small bowel obstruction
- Female infertility
- Chronic pelvic pain
Adhesions are asymptomatic, it is the effect of them that present with clinical features
How are bowel adhesions managed when they cause a small bowel obstruction?
Conservative (if uncomplicated obstruction)
- Tube decompression
- NBM
- IV fluids
- Adequate analgesia
Surgical (if above failed or ischaemia or perforation)
- Adhesiolysis only of adhesions causing obstruction
- Usually laparoscopic but can switch to open
What are some risk factors for developing an incisionial hernia post abdominal surgery?
- Emergency surgery
- Wound type
- BMI>25
- Midline incision
- Wound infection
- Preoperative chemotherapy
- Intraoperative blood transfusion
- Advancing age
- Pregnancy
- Smoking
How does an incisional hernia present?
- Non-pulsatile, reducible, soft and non-tender swelling at or near site of previous surgical wound
If incarcerated will show signs of bowel obstruction e.g N+V, abdominal distension, absolute constipation
Clinical diagnosis!!
What are some complications of incisional hernia repair?
- Bowel injury
- Seroma formation
- Recurrence
- Chronic pain due to tension in mesh and nerve entrapment
What is the aetiology of constipation on a surgical ward?
<3 bowel movements a week that are hard, dry and difficult to pass
- Postop ileus
- Bowel obstruction
How is post-operative constipation managed?
Conservative: sufficient dietary fibre, treat underlying cause, hydration, early mobilisation
Pharmacological: laxatives, usually if hard stool give stool softening and glycerin suppository to help soften stool initially.
If post-op ileus, opioid induced or soft stool need stimulant laxative
Last resort: manual evacuation or enema
