passmed Flashcards
aortic dissection patho + associations
tear in TUNICA INTIMA of wall of AORTA ASSOC: -HTN (most imp RF) -trauma -bicuspid aortic valve -collagens - MS, EDS -Turners + Noonans -pregnancy -syphillis
aortic dissection features
chest/back pain TEARING + radiates to intrascapular region
pulse DEFICIT - weak or absent carotid, brachial, or femoral pulse, variation (>20 mmHg) in SBP bet the arms
Aortic REGURGITATION (EDM, LLSE) - from prox dissection involving aortic valve leaflets
HTN
Other features -
-coronary arteries –> angina
-spinal arteries –> paraplegia
-distal aorta, subclavian or femoral a –> limb iscahemia
-renal arteries –> anuria + loin pain
-mesenteric arteries –> abdo pain
minority of pts get ST elevation in inferior leads
aortic dissection classification
Stanford classification:
type A - asc aorta - 2/3 of cases
type B - desc aorta - distal to left subclavian origin - 1/3 cases
aortic dissection Ix + Mx
It’s imp to remember that pts may pres acutely and be clinically unstable.
Ix:
1.CXR - widened mediastinum
2.CT angiography of the CAP is the Ix of choice
suitable for stable pts + for planning surgery
-a false lumen is a key finding in diagnosing aortic dissection
3.TOE - more suitable for unstable pts who are too risky to take to CT scanner
Mx:
Type A: surgical MX, but BP should be controlled to a target systolic of 100-120 mmHg whilst awaiting intervention
Type B*: conservative management, bed rest, reduce blood pressure, IV labetalol to prevent progression
HHS pathophysiology + does it have higher or lower mortality than DKA
PATHO: Hyperglycaemia results in OSMOTIC DIURESIS with assoc LOSS of SODIUM + POTASSIUM
- Severe volume depletion results in a significant raised serum osmolarity (typically > than 320 mosmol/kg), –> in HYPERVISCOSITY of BLOOD.
- Despite these severe electrolyte losses and total body volume depletion, the typical patient with HHS, may not look as dehydrated as they are, because hypertonicity–> to preservation of INTRAVASCULAR VOLUME.
-HIGHER mortality than DKA + may be complicated by vascular complications eg MI, stroke or peripheral arterial thrombosis
HHS features occur over days 4x main categories
General - fatigue, lethargy, N+V
Neuro - alt level of consciousness, H, papilloedema, weakness
Haem - hyperviscosity (–> MI, Stroke + peripheral arterial thrombosis)
CV - dehydration, hypotension, tachy
HHS Dx
- Marked HYPERGLYCAEMIA (>30 mmol/L)
- Raised SERUM OSMOLARITY (> 320 mosmol/kg)
- Hypovolaemia in absence of ketoacidosis (pH>7.3, HCO3 >15)
Note: A precise definition of HHS does not exist, however the above 3 criteria are helpful in distinguishing between HHS and DKA. It is also IMP to remember that a mixed HHS / DKA picture can occur.
HHS goals of mx summary
The goals of management of HHS can be summarised as follows:
1. Normalise the OSMOLALITY (gradually)
the serum osmolality is the key parameter to monitor
if not available it can be estimated by 2 * Na+ + glucose + urea
2. Replace FLUID and electrolyte losses - 1st line = IV 0.9% NaCl initially 1L over 1-2hrs
3. Normalise blood glucose (gradually)
Tx of thyroid storm (from untreated hyperthyroidism) TRIAD
Conservative measures - FLUIDS, COOLING
- Propanolol
- PTU (propylthiouracil)
- Steroids
digoxin poisoning presentation
dizzy, N+V
palps
bradycardia (w/o hypotension)
YELLOW-GREEN colour disturbance (xanthopsia)
VISUAL HALOES
confusion
HYPERkalaemia (nb. hypokal = RF for toxicity)
ECG - downsloping ST segment = Salvador Dali moustache or REVERSE TICK SIGN
digoxin poisoning mx
- Immediate digoxin level
- IV fluds
- correct elctrolyte abn
- cont cardiac monitoring
- give DIGIBIND if levels >15 after 6h of last dose, level>10 within 6h of last dose, symptomatic
charcots triad of ascending cholangitis
- RUQ pain
- Fever/raised WCC
3.Jaundice
= infection of the bile duct
Reynolds Pentad
- RUQ pain
- Fever/raised WCC
3.Jaundice
+ SHOCK (low BP)
+ ALTERED MENTAL STATE
= greater severity of infection
what is best prognostic marker in paracetamol OD
PROTHROMBIN TIME
- marker of clotting function = synthetic ftn of the liver
- Kings college criteria can be used in pts with acute liver failure to assess prognosis + assessement for liver transplant
define + mx of Torsades De Pointes
=rare, polympohic VT where QRS axis is constantly shifting + typically prolonged QTc interval on ECG >0.45s
UNSTABLE pts with haemodynamic compr = DC cardioversion
STABLE pts - IV Mg Sulphate 2g over 1-2 mins
Causes of LONG QT INTERVAL (TIIMMES)
Toxins - drugs incl anti-arrythmics, anti-psychotics, TCAs
Inherited - congenital long QT eg Romano ward + Jervell + Lange-Nielson syndr
Ischaemia
Myocarditis
MV prolapse
Electrolyte abnormalities - hypokalaemia + hypocalcaemia
SAH
aspirin OD early sign on ABG
RESP ALKALOSIS - due to stimulation of the BS medullary respiration centre = SOB
–> later MET ACIDOSIS
differentiating gastric vs duodenal ulcers
gastriic ucler pain WORSE when eating due to acid secretion
duod ulcer pain WORSE few HOURS after eating as this is when pyloric sphincter relaxes to allow ACIDIC FOOD contents INTO DUODENUM
CO poisoning features + tx
confusion, N+V, cherry red skin, pink mucosa, tachy, 100% on oxygen sat (similarities bet oxyhaemoglobin + carboxyhaemoglobin), hyperpyrexia, extrapyramidal features, coma
tx - 100% oxygen NRB. mask
features of LIFE - THR ASTHMA - 33,92. CHEST
PEF <33% S02<92% Cyanosis Hypotension Exhaustion, alt consciousness Silent chest Tachyarrythmias \+ NORMAL C02
high CO2 in asthma immediate Mx
NEAR FATAL ASTHMA
-admit to ITU
fluid overloaded pt on 40mg Furosemide with eGFR of 25 , what to do with diuretic therapy?
INCR DOSE FUROSEMIDE TO 80mg IV
- furosemide = loop diuretic , works on THICK ASC LoH, targets NaKCl cotransporter on APICAL MEMBR
- so it must first be filtered into the tubules by glomerulus to have diuretic action
- so in pts with poor renal ftn, dose must be INCR so an INCR CONC reaches glomerulus + tubules –> adequate diuresis
Ix to detect anastomotic leak 5d post surgery
CT abdo pelvis with rectal contrast
- detect presence + location + degree of leak which guides further Mx
- alt test = fluoroscopic water-soluble enema
Mx of acute pulmonary oedema
A-E approach
sit pt up
oxygen
ensure IV access
IV furosemide
Consider NIV eg CPAP if failed medical therapy
Consider invasive ventilation + INOTROPIC support if above fails
