SC03 - Anaesthesiology - Post-operative complications and management Flashcards
List possible complications post anaesthesia
Airway
- Compromised airway patency (e.g. vomiting, tongue obstruction, blood…etc)
Breathing:
- Hypoventilation
- Hypoxia
Circulation
- Hypotension/ hypertension
- Arrhythmias
Neurological:
- Confusion/ over sedation
- Stroke/ CVA
Others:
- Pain
- PONV
Post-anesthesia care unit
- Standard care procedures
- Check ABC
- 30-40% O2 for GA patients
- Monitor vitals: BP, Pulse, Temp., Pulse oximeter, RR, fluid IO chart and UO
Airway obstruction post-op
Causes
Signs
Management
Causes:
- Tongue falling back
- Laryngospasm
- Secretions
- Vomitus
- Blood
- External pressure on trachea
- Foreign body: e.g. gauze packing
Signs:
- Stridor/ Stretor
- Airway cessation at mouth/ nose, no breath sounds, no chest expansion
Mx:
- Triple airway maneuver: head tilt, chin lift, jaw thrust
- Give oxygen
- Airway adjuncts: nasopharyngeal airway
- Suction blood, vomitus, remove FB
- Endotracheal intubation
Hypoventilation post-op
Causes
- Low respiratory drive: residual anesthesia, opioid overdose, CNS pathologies
- Poor repiratory muscle function: residual muscle paralysis, Pain inhibiting respiration, External compression (obesity, gastric distension, tight wound dressing)
- Exacerbation of pulmonary diseases (e.g. COPD, Asthma, Pneumothroax)
Hypoventilation post-op
Management
- ABC
- Oxygenation and ventilation (simple, advanced airway)
- Find underlying case: resp. drive? Muscle? Pulmonary conditions?
- Check drug chart for opioid or BDZ overdoze, give Naloxone or Flumazenil
- Check residual muscle relaxant effect
Hypoxaemia post-op
Definition
Causes
Definition: Spo2 < 90% or Pao2< 8kpa
Causes:
Respiratory causes:
*Hypoventilation
*Atelectasis
*Lobar/ Segmental Collapse
*Aspiration
*Pulmonary Oedema
*Pneumothorax
*Bronchospasm
Circulatory causes:
*Hypotension
*Reduced cardiac output
High metabolic demand
*Fever
*Shivering
Hypoxaemia post-op
Management
- ABC, oxygenation and ventilation
- Monitoring: Pulse oxiumetry, arterial blood gas, temperature
- Respiratory investigations: CXR, Bronchoscopy, CT lung
- Cardiac investigations: ECHO, ECG
Hypotension post-op
Causes
Hypovolemia:
- Dehydration due to long-fasting, fluid shift during surgery, fever, vomiting and diarrhea
- Blood loss during operation
Distributive problem:
- Sepsis/ anaphylatic shock
- High spinal block
- Vasodilation due to anesthesia, anti-hypertensives
Cardiogenic problems:
- MI, arrhythmia, ventricular dysfunction, valvular disease
Obstructive causes:
- PE, Tamponade, Pneumothroax
- Fat/air/amniotic fluid embolism
Hypotension post-op
Management
Continuous BP monitoring: Arterial line/ CVP
Find obstructive or cardiogenic causes: ECG, ECHO
Hypovolemia: Bloods, RFT, clinical exam for perfusion
Monitor perfusion: Cardiac monitor, urine output, GCS monitoring
Hypertension post-op
Definition
Causes
Definition:
- Systolic >180 mmHg, diastolic >100 mmHg
- 20% more than baseline
Causes:
* Pain/ Discomfort e.g. Foley, full bladder, confusion
* Hypoxia/hypercapnia
* Iatrogenic
* Metabolic: thyroid storm, malignant hyperthermia
* Raised intracranial pressure
* Pre-existing hypertension
Management:
- ABC
- Exclude and treat pain/ discomfort
- Investigate metabolic, respiratory, neurological causes
- Drug therapy: BB, GTN
Arrhytmia post-op
Causes
- Hypoxia/ hypercapnia
- Electrolyte/ acid-base disturbances
- Myocardial ischaemia
- Fever/ hypothermia
- Pre-existing heart disease
- Pain & anxiety
- Endocrine disorders
Delirium post-op
Definition
High risk demographic
Causes
Definition: Acutely altered and fluctuating mental status with inattention and an altered level of consciousness
High risk: elderly, pre-existing cognitive impairment, vascular surgeries, hip fracture surgery
Causes:
* Pain or other discomfort
* Hypoxia
* Hypotension
* Cerebral hypoxia
* Cerebral injury
* Electrolyte or endocrine imbalances
* Drugs: ketamine, drug withdrawal, anticholinergic
Delirium post-op
Management
- ABC
- Neurological exam: Focal signs, GCS
- Monitor Electrolytes, glucose, temperature, BP, SpO2
- CT brain to r/o neurological causes
- Review drug charts
- Consider sedation or anti-psychotics if treatable cause excluded
Hypothermia post-op
Definition
Risk factors
Sequalae
Definition: core temp <35 (rectal temp)
Risk:
- Paediatrics or elderly
- Excessive exposure of viscera/ skin
- Prolonged operature
- Administer cold fluid/ no pre-warming of blood products e.g. massive emergency transfusion
Sequalae:
- CVS: MI, arrhythmia (esp. VF), coagulopathy, O2-Hb dissociation curve left shift causing hypoxaemia, hypotension, pulmonary edema
- Increased shivering and O2 consumption
- Increase wound infection risk
- Neurological: abnormal tone and reflex, diminished consciousness, parasthesia
- Decrease drug metabolism
List one clinical pain scale
Wong-Baker FACES pain rating scale
PONV
Risk factors
Risk stratification system
Management
Risk:
- Female
- History of PONV/ motion sickness
- Non-smoker
- Post-op opioids
- Anaesthetic risks: duration, use of nitric oxide, etomidate
- High risk surgeries: Middle ear surgery, laparoscopic surgeries
Risk stratification: Apfel score
Management
- ABC
- Monitor vitals
- Investigate neurological and surgical causes
- Treat pain and post-op anxiety
- Investigation hydration and electrolyte imbalances
- Drugs: anti-emetics (ondansetron, Tropisetron, Dexamathesone (others: D2 antagonist, H1 blocker, Anti-cholinergics…etc)
