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Stress Dose Steroids

WHEN IS STRESS DOSE STEROIDS INDICATED?

  • depends on history of steroid intake and likelihood of HPA supression + type and duration of surgery
  • NONSUPPRESSED HPA AXIS: 
    • < 3 weeks of steroids at any dose
    • prednisone <5mg/daily for any duration
    • prednisone <10mg every other day
    • PLAN:  continue same regimen perioperatively; no need for cosyntropin test or stress dose steroids
  • SUPPRESSED HPA AXIS
    • prednisone >20mg/day x 3 weeks or more OR Cushingoid appearance
    • PLAN:
      • give stress dose steroids based on type and duration of surgery (see below)
  • INTERMEDIATE HPA SUPPRESSION (Unknown HPA Axis suppression, previous 3 or more intraarticular or spinal steroid injections within 3 mos prior to suregery)
    • PLAN
      • evaluate HPA axis 
        • check AM cortisol (8a.m.) after 24h off steroids
        • if <5 ug/dL – likely suppressed axis; give stress dose steroids
        • if >10 ug/dL – likely no supression; continue current dose on day of surgery
        • if 5-10 ug/dL – ACTH stim test or empiric stress dose steroids
      • ACTH stim test (standard is 250 ug):
        • if serum cortisol <18 ug/dL 30 mins after ACTH – give stress dose steroids
        • if >serum cortisol >18 ug/dL 30 mins after ACTH – no stress dose steroids

 

STEROIDS BASED ON TYPE AND DURATION OF SURGERY

MINOR PROCEDURES / LOCAL ANESTHESIA – stress dose not necessary, take AM steroids

MODERATE SURGICAL STRESS: (eg. LE revascularization, total joint replacement)

  1. take AM steroids
  2. hydrocortisone 50mg IV prior to procedure, 25mg IV q8h x 24h
  3. resums usual dose after

MAJOR SURGICAL STRESS (e.g open heart surgery, proctocolectomy, esophagogastrectomy)

  1. take AM steroids
  2. hydrocortisone 100mg IV before induction of anesthesia
  3. hydrocortisone 50mg q8h x 24h
  4. taper by half per day to maintenance dose

 

 

 

Reference:

Uptodate.com. (2018). UpToDate. [online] Available at: http://www.uptodate.com/contents/the-management-of-the-surgical-patient-taking-glucocorticoids?search=stress+dose+steroids&source=search_result&selectedTitle=1~60#H6 [Accessed 25 Mar. 2018].

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MRI evolution of Cerebral Abscess

img_1682.jpg

 

Reference:

Criner, G., Barnette, R. and D’Alonzo, G. (2010). Critical Care Study Guide. Dordrecht: Springer.

 

 

Pulmonary Artery Catheter Waveforms and Normal Values

As the PAC is inserted, the following waveforms can be observed.

1. When the catheters enters the RA, a CVP tracing is seen – characterized by a and v waves.img_1652

 

 

 

 

 

 

 

 

 

2. As the catheter enters the RV, a sharp increase in systolic pressure is noted.img_1653

3. As the catheter is advanced to the pulmonary artery, an increment in diastolic pressure is seen as well as the presence of a dichromatic notch. img_1654

4. When the catheter is advanced further into the pulmonary artery, and wedged – a sine wave that oscillates with respiration is seen. img_1655

THE RA WAVEFORM:

The RA waveform is characterized by presence of 2 waves: a wave (contraction of the RA) and the v wave (passive filling of the RA).

The x descent represents RA relaxation, which is interrupted by the c wave which represents closure of the tricuspid valve.

The y descent follows the v wave, which signals the opening of the tricuspid valve and exit of blood from the RA to the RV.

img_1656

OVERDAMPING:

The wave below illustrates flushing of the catheter – which results in high pressures in the transducer (1). Flushing stops, and results in fall in pressures and an overshoot (2), and a return to normal waveform.

img_1661

The wave below – overshooting is absent, and the waveform is flattened, which is found in an overdamped waveform. Overdamping can be caused by a kinked catheter, air bubbles, fibrin clot.

img_1662

 

 

 

 

 

CATHETER WHIP.

The graph below illustrate catheter whip – where ventrcicular contractions are transmitted to the PAC.

img_1663

OVERWEDGING:

The arrow indicates when the balloon is inflated. There is a sustained increment in pressure reading.

img_1664

 

 

 

 

ACUTE MITRAL INSUFFICIENCY

Prominent v waves represent blood that enters the LA during ventricular systole due to an incompetent mitral valve.

img_1665

 

 

 

 

TRICUSPID REGURGITATION

Broad c-v waves can be seen.

img_1666

 

 

 

 

 

RV INFARCTION

Marked acute dilatation of the RV occurs. Acute dilatation is limited by the pericardium. Deep x and y descents, resembling the letter W is seen.

img_1667

 

 

 

 

 

MEASURED HEMODYNAMICS VARIABLES:

img_1648

DERIVED HEMODYNAMICS VARIABLES

img_1649

OXYGEN TRANSPORT VARIABLES

img_1650

Reference:

Criner, G., Barnette, R. and D’Alonzo, G. (2010). Critical Care Study Guide. Dordrecht: Springer.

Formulae: Acid-base disorders

img_1647

 

 

Reference:

Criner, G., Barnette, R. and D’Alonzo, G. (2010). Critical Care Study Guide. Dordrecht: Springer.

Pediatric GCS (Glasgow Coma Scale)

img_1646

 

 

 

References

Garvin, R. and Mangat, H. (2017). Emergency Neurological Life Support: Severe Traumatic Brain Injury. Neurocritical Care, 27(S1), pp.159-169.

Rapid ACTH Stimulation Test

Popular but often unnecessary test

  • – perform at any time of day or night
  • – obtain blood sample for baseline (random) plasma cortisol level
  • – give synthetic ACTH IV (Cosyntropin) 250 ug X11
  • – repeat plasma cortisol 1 hour after injection

 

ADRENAL SUPPRESSION:

  1. Random cortisol <10 ug/dL OR
  2. Increment in plasma cortisol <9 ug/dL after ACTH

img_1626

APPROACH

  • – check random plasma cortisol
  • – if >=35 ug/dL – likely normal or adequate adrenal function
  • – if <10 ug/dL – evidence of adrenal suppression
  • – if 10-34 ug/dL – do rapid ACTH stim test as above

** In septic shock, do not check cortisol levels – trial of IV hydrocortisone is recommended if hypotension refractory to volume resuscitation.

 

Reference:

Marino, P. (n.d.). The ICU book.

Encephalopathy Work-up

Screening tests

  • Serum glucose, electrolytes, calcium/phosphorus, uric acid, lactate and pyruvate, liver, renal and thyroid function tests, blood gasses
  • Prolactin levels (10 to 20 min after suspected seizure, diagnosis seizure vs. psychogenic nonepileptic seizure)
  • Serum CK
  • ANA, ENA, ANCA, RF, complement, ACE, anti-thyroglobulin and anti-thyroperoxidase antibodies (Hashimoto disease), autoantibody panel (thyroid antimicrosomal, antiparietal),  immunoglobulins
  • Serum ceruloplasmin and copper, 24h urinary copper, slit lamp, liver biopsy (WD)
  • CBC, ESR, CRP, plasma fibrinogen
  • Coagulation profile (protein C and S, ATIII, Factor Leiden V, APLS, anticardiolipin)
  • Serum vitamin B12 and folic acid
  • RPR, TPHA
  • Serum cortisol, PTH and osmolality.
  • Serology: HIV, HSV, adenovirus, CMV, Coxsackie, polio, echovirus, hepatitis (A,B,C), parvovirus B19, mycoplasma, toxoplasma, VDRL, cysticercosis
  • Blood and urine organic acids and carnitine
  • Chest X-ray
  • PPD
  • Echocardiogram
  • EEG (non-convulsive status epilepticus), VEP, EMG/NCVs
  • Brain MRI, MRA
  • Conventional angiogram (CNS vasculitis)
  • serum ammonium

CSF

  • Besides routine analysis (chemistry, cell count, smear and stainings): lactate and pyruvate (mitochondrial disease), oligoclonal bands, IgG index, VDRL, viral (measles titer), fungal, PCR (T. Whippleii, JC virus, HSV, CMV, VZV), Ziehl staining, repeated cytology,
  • anti-thyroglobulin and anti-thyroperoxidase antibodies (Hashimoto disease).

Specific investigations

Blood/serum

  • 14-3-3 protein (CJD) (stable at room temperature and can be sent by regular mail)
  • Aminolevulinic acid, porphobilinogen, uroporphyrins, coproporphyrin
  • Antineural nuclear antibodies (ANNA-1(=Anti-Hu), ANNA-2 (=anti-Ri), ANNA-3, Purkinje cell cytoplasmic antibodies (PCCA-1 (=anti-Yo), PCCA-2, PCCA-Tr and mGluR1), plasma membrane cation channel antibodies (CV2/CRMP-5, Ma1, Ma2/Ta, amphiphysin, striational, voltage gated calcium channels (VGCC) and voltage gated potassium channels (VGKC), anti-NMDA-R (NR1 and NR2) antibodies.
  • Methylmalonic acid, VLCFA, arylsulphatase, homocysteine

Biopsy

  • Conjunctiva (sarcoidosis),
  • Small bowel (Whipple disease)
  • Skin (SLE, vasculitis, CADASIL)
  • Brain biopsy

COMA Algorithm (ENLS 2017)

Neurologic Etiologies of Coma

Toxic-Metabolic Etiologies of Coma

Reference:

“Acute Encephalopathy Work-Up.” Neuroweb.us. http://www.neuroweb.us/Chapters/acute%20encephalopathy/work_up.htm, 2017. Web. 18 Aug. 2017.