Causes

Ventilator Associated Pneumonia (VAP)

Define: Pneumonia as defined by a new infiltrate on chest x-ray plus two or more other factors after mechanical ventilation. These factors include temperature of >38 °C or <36 °C, a white blood cell count of >12 × 109/ml, purulent secretions from the airways in the lung, and/or reduction in gas exchange.

 

Risk factors for MDR pathogens:

  • Hospitalisation > 5 days
  • Antibiotic in preceding 90 days
  • Immunosuppression

Pathogens: Pseudomonas, Klebsiella, Acinetobacter, MRSA

Pathogenesis:

  • Aspiration
  • Leakage around cuff
  • Inhalation
  • Direct incubation
  • Haematogenous spread

Diagnosis:

  • Radiology showing new/progressive lung infiltrate
  • Temperature>38 degree celsius
  • WBC increases/decreased
  • Purulent secretions
  • Blood culture
  • Thoracocentesis of pleural effusion
  • ETT aspirate
  • BAL
  • PSB

 

Treatment

..Even if tracheal colonisation but no sign of systemic infection

Empiric antiobiotic:

  • Monotherapy
    • Nonpseudomonal ceftriaxone OR
    • Ampicillin/sulbactam OR
    • Fluoroquinolone
  • Combination therapy
    • Aminoglycoside OR
    • Antipseudomonal fluoroquinolone PLUS
    • Antipseudomonal penicillin (ceftazidime, cefepime) OR
    • Carbapenem (Meropenem)

 

Evaluate response, followed by trace cultures to narrow within 7 days

 

*Prevention*

Modifiable risk factors:

General

  • infection control
  • surveillance of ICU infection

VAP

  • Avoid ETT/IPPV
  • Aspirate secretions
  • Semirecumbent
  • Cleaning and sterilisation of equipment
  • ?SDD

 

Cardiomyopathy Classification

WHO Definition:

Disease of heart muscle without apparent precipitating cause

Classically Idiopathic or due to Secondary cause

International Society of Cardiology Task Force

  • Dilated Cardiomyopathy – 1 in 200,000, Familial 20-30%
  • Hypertrophic Cardiomyopathy
  • Restrictive Cardiomyopathy
  • Arrythmogenic Cardiomyopathy
  • Left Ventricular Non Compaction Cardiomyopathy

Management

  1. Basics of safe anaesthesia
  2. Detailed history
  3. Appropriate examination
  4. Arrange investigations
  5. Consider underlying disease
  6. Manage medications
  7. ICD management

MBRRACE-UK 2009-1012 Summary

Maternal deaths decreased from 11 to 10 per 100,000

Lessons for Anaesthesia: 7 Deaths

Complications after post-dural puncture headache: 2 deaths
  • Two women died who had experienced accidental dural taps while undergoing epidural cannula placement. One underwent a blood patch; the other was treated conservatively.
  • Neither had hospital follow up or GP referral after discharge.
  • Both women experienced headaches for some weeks before emergency presentations with what turned out to be cerebral vein thrombosis in one case and subdural haematomata in the other
Hypoventilation during or after general anaesthesia: 2 Deaths
  • Two women experienced prolonged hypoventilation during or following general anaesthesia for treatment of postpartum haemorrhage.
  • Both women were overweight.
  • In one case, hypoventilation occurred during anaesthesia and may have resulted from undiagnosed bronchospasm. The tracheal tube was removed and replaced more than once.
  • In another case, hypoventilation occurred after extubation and may have occurred for a prolonged period of time before re-intubation took place. Monitoring throughout this period was inadequate
Collapse after anaesthesia: 2 deaths
  • Two women collapsed after anaesthesia; one following an epidural top-up and one following wound infiltration with 20 ml bupivacaine 0.5% at the end of a caesarean section.
  • In both cases there was careful consideration of the possible differential diagnosis including early administration of Intralipid to counteract possible intravenous local anaesthetic, even though the role of local anaesthetic in the sequence of events was uncertain.
  • There was prompt recognition and management of collapse, involvement of senior staff, and appropriate uterine displacement during CPR and peri-mortem caesarean section in the woman who collapsed before delivery.
  • Ultimately the deaths were not attributed to anaesthesia
Hyperkalaemia: 1 death
  • A previously healthy woman developed preeclampsia and mild renal impairment and underwent uncomplicated elective caesarean section under spinal anaesthesia.
  • Diclofenac was given rectally for postoperative analgesia.
  • She was found to be hyperkalaemic several hours postoperatively but despite referral to critical care, no treatment was instituted despite a second test result confirming severe hyperkalaemia, with worsening renal function.
  • She suffered a cardiac arrest a few hours later, from which she could not be resuscitated

CEMACE 2006-2008 Summary

7 Maternal Deaths Associated with Anaesthesia

Failure to ventilate: 2 deaths

1st patient:

  • Unable to intubate on 1st attempt.
  • Could ventilate via iLMA.
  • 2nd attempt unrecognised oesophageal intubation.
  • Cricothyroidotomy not attempted.
  • Working epidural not topped up until entered the operating theatre (Too late as urgency escalated to Cat 1)

2nd patient:

  • Patient with known airway problem and difficulty with tracheostomy
  • She was turned in bed and tracheostomy fell out
  • Died in ICU

Post-operative complications: 4 deaths

1st patient:

  • Use of opiate PCA died from opiate toxicity.

2nd patient:

  • Incompatible blood transfusion resulted in acute circulatory failure and subsequent death.

3rd patient:

  • Patient was unknown to be a substance abuser died whilst recovering from general anaesthesia for a surgical abortion. It is thought that IV syntometrine caused the cardiac arrest.

4th patient:

  • Aspiration on emergence after a GA for Cat 1 LSCS

Leucoencephalitis: 1 death

A patient had an uneventful spinal anaesthetic for LSCS and died a few days later. Autopsy revealed acute haemorrhagic disseminated leucoencephalitis (Hurst’s disease), and an empyema in the spinal canal covering the lumbar and lower thoracic region. This is an autoimmune disease that can be triggered by an infection – likely the empyema.

Deaths to which anaesthesia contributed

Anaesthesia management was thought to have contributed to the outcome in a further 18 deaths:

  • Failure to recognise serious acute illness
  • Failure to consult senior staff in a timely manner –This was notable in women suffering from pre-eclampsia or eclampsia where substandard care was noted in 8 deaths.
  • Failure to consider puerperal sepsis a life-threatening emergency. Emergency management should include blood cultures, early administration of broadspectrum antibiotics, careful fluid resuscitation, inotropic support, and monitoring in a critical care ward. Medical staff should be aware that pregnant women are at increased risk of developing pulmonary oedema when compared with non-pregnant patients.
  • Failure to recognise postpartum haemorrhage. Women at risk of PPH should be closely monitored, and a high suspicion maintained for concealed bleeding.

Classification of Congenital Heart Disease

Defects that Decrease Pulmonary Blood Flow – Tricuspid atresia, ToF

Defects that Increases Pulmonary Blood Flow – ASD, VSD, AV canal defects, Persistent PDA

Defects that cause Obstruction to Blood Flow from Either the Left or Right Ventricle – coarctation of the aorta, aortic stenosis, pulmonary stenosis

Defects that cause Mixed Blood Flow Anomalies – Transposition of the Great arteries, Hypoplastic Left Heart Syndrome

Acidosis FLOW CHART & Compensation Calculations Abbreviated

EASY TO REMEMBER FLOW

IMPORTANT AND COMMON ICU/ANAESTHESIA TOPIC

Increased anion gap
  • Lactic acidosis
    • Tissue hypoxia- Septic shock, Anaemia, CO low, Cyanide
    • Non tissue hypoxia- Terbutaline, Nitroprusside, Phaechromocytoma (Increased catecholamines), Biguanides
  • Ketones
    • High glucose- DKA
    • Normal glucose- starvation, alcoholism
  • Renal failure
  • Acetazolamide
  • Osmolar gap
    • High (>12) Ethylene glycol, Methanol
    • Normal- Aspirin, salicylates, paraldehyde
Normal anion gap
  • Hyperchloraemia- RTA, NaCl
  • Normal- diarrhoea, Ileostomy

In Respiratory Acidosis:

Chronic acidosis CO2 compensation 4x HCO3

Acute acidosis CO2 compensation 1x HCO3

In Metabolic Acidosis:

CO2= (1.5x HCO3) + 8

Causes of Hyponatraemia

Simplest Points for the ICU VIVA

Hyperosmolar

Hyperglycaemia

Mannitol infusion

Isoosmolar

Hyperlipidaemia

Hyperproteinaemia

TURP

Hypoosmolar

Hypervolaemia

Fluid overload, nephrotic syndrome, cirrhosis, AKI, advanced renal failure

Normovolaemia

SIADH,

Hypothyroidism,

Glucocorticoid deficiency

idiopathic

severe strenuous exercise

Psychogenic polydipsia

Drugs(resembling SIADH)- desmopressin, phenytoin, carbamazepine

Hypovolaemia

Vomiting

Salt losing renal disease

Diarrheoa

Gastric suction

Addison’s

Repeated ascitic tap

IVIg when mixed with maltose and given to renal failure patients

Diuretics