MRI and the Critically Ill
MRI and the Critically Ill: Restricted access to patients; Remote monitoring; MR compatible equipment; Safety of patients and staff; Getting the highest quality scan possible
Category Investigations
Osmolar Gap
Osmolar Gap: Osmolar gap = Osmolality (measured) - Osmolarity (calculated): NOTE: is a pragmatic clinical aid - the units are different (osmolality =mOsm/kg and osmolarity = mOsm/L) so it doesn't make mathematical sense!
Spinal Imaging
Spinal Imaging: CT is the best way to image the spine for bony injuries (will miss 6% of discoligamentous injuries). If suspected soft tissue or spinal cord injury -> patient requires an MRI
Spirometry
Spirometry
Stool specimens
OVERVIEW microscopy and culture is useful in community acquired diarrhoeal syndromes (not useful otherwise) in-hospital:— blood = ischaemic bowel or surgical cause— diarrhoea = rule out Clostridium difficile infection MICROSCOPY parasites, cysts, ova: giardia, cryptosporidium, blastocystis red and white cells:…
Synovial fluid analysis
Synovial fluid analysis: - appearance; WCC; RBC; microscopy + culture; protein; LDH; glucose; crystals
Ultrasound in Critical Care
Ultrasound in Critical Care: many roles; increasing applicability in emergency medicine and ICU
Urinalysis
CCC overview of urinalysis
Bleeding Time
Bleeding time
Bone Marrow Biopsy
Bone Marrow Biopsy: Confirm diagnosis. Allows therapy to be targeted. Needs to be done only, if the answer cannot be seen from peripheral blood already.
Coagulation Profile
OVERVIEW Prothrombin Time Activated Partial Thromboplastin Time Thrombin Time Fibrinogen Fibrin Degradation Products (FDP’s) APTT 50% NP Retiplase Time Euglobin Lysis Time Urea solubility Test PROTHROMBIN TIME thromboplastin added tests the extrinsic pathway ratio compared to control (INR) tests factors:…
D-dimer
D-dimer specific for fibrin breakdownsensitivity = 95%specificity = 50%