MRCS 1 Flashcards
NICE guidelines stress vs urge urinary incontinence
Initial assessment urinary incontinence should be classified as stress/urge/mixed.
At least 3/7 bladder diary if unable to classify easily.
Start conservative treatment before urodynamic studies if a diagnosis is obvious from the history
Urodynamic studies if plans for surgery.
Stress incontinence: Pelvic floor exercises 3/12, if fails consider surgery.
Urge incontinence: Bladder training >6/52, if fails for oxybutynin (antimuscarinic drugs) then sacral nerve stimulation.
Pelvic floor exercises offered to all women in their 1st pregnancy.
What is stress inconcinence
50% of cases, especially in females.
Damage (often obstetric) to the supporting structures surrounding the bladder may lead to urethral hypermobility.
Other cases due to sphincter dysfunction, usually from neurological disorders (e.g. Pudendal neuropathy, multiple sclerosis).
Urethral mobility:
Pressure not transmitted appropriately to the urethra resulting in involuntary passage of urine during episodes of raised intra-abdominal pressure.
Sphincter dysfunction:
Sphincter fails to adapt to compress urethra resulting in involuntary passage of urine. When the sphincter completely fails there is often to continuous passage of urine.
Urge incontinence
In these patients there is sense of urgency followed by incontinence. The detrusor muscle in these patients is unstable and urodynamic investigation will demonstrate overactivity of the detrusor muscle at inappropriate times (e.g. Bladder filling). Urgency may be seen in patients with overt neurological disorders and those without. The pathophysiology is not well understood but poor central and peripheral co-ordination of the events surrounding bladder filling are the main processes.
Which of the following is the equivalent of cardiac preload?
Preload is the same as end diastolic volume. When it is increased slightly there is an associated increase in cardiac output (Frank Starling principle).
Which of the following is responsible for the release and synthesis of calcitonin?
Secreted by C cells of thyroid and
Inhibits intestinal calcium absorption
Inhibits osteoclast activity
Inhibits renal tubular absorption of calcium
Which of the substances below is derived primarily from the zona reticularis of the adrenal gland?
Zona glomerulosa Outer zone Aldosterone
Zona fasiculata Middle zone Glucocorticoids
Zona reticularis Inner zone Androgens
Which part of the jugular venous waveform is associated with the closure of the tricuspid valve?
JVP: C wave - closure of the tricuspid valve
a’ wave = atrial contraction
‘c’ wave
closure of tricuspid valve
‘v’ wave
due to passive filling of blood into the atrium against a closed tricuspid valve
‘x’ descent = fall in atrial pressure during ventricular systole
‘y’ descent = opening of tricuspid valve
PE blood gas?
combination of hypoxia and respiratory alkalosis should suggest a pulmonary embolus. The respiratory alkalosis is due to hyperventilation associated with the pulmonary embolism.
What decreases the functional residual capacity?
Is the volume of air remaining in the lungs at the end of a normal expiration.
FRC = RV + ERV. 2500mls.
Pulmonary fibrosis Laparoscopic surgery Obesity Abdominal swelling Muscle relaxants
What increases functional residual capacity?
Increased FRC:
Erect position
Emphysema
Asthma
Which part of the ECG represents atrial depolarization?
The P wave represents atrial depolarization. Note that atrial repolarization is obscured within the QRS complex.
T wave
Represents ventricular repolarization and is longer in duration than depolarization
Triad of Wernicke encephalopathy:
Acute confusion
Ataxia
Ophthalmoplegia
Describe Monroe-Kelly doctrine.
considers the skull as a closed box. Increases in mass can be accommodated by loss of CSF. Once a critical point is reached (usually 100- 120ml of CSF lost) there can be no further compensation and ICP rises sharply.
The next step is that pressure will begin to equate with MAP and neuronal death will occur. Herniation will also accompany this process.
lumbar puncture performed
Samples of CSF are normally obtained by inserting a needle between the third and fourth lumbar vertebrae. The tip of the needle lies in the sub arachnoid space, the spinal cord terminates at L1 and is not at risk of injury. Clinical evidence of raised intracranial pressure is a contraindication to lumbar puncture. Composition Glucose: 50-80mg/dl Protein: 15-40 mg/dl Red blood cells: Nil White blood cells: 0-3 cells/ mm3
CPP calculation
Cerebral perfusion pressure= Mean arterial pressure - intra cranial pressure
The cerebral perfusion pressure (CPP) is defined as being the net pressure gradient causing blood flow to the brain. The CPP is tightly autoregulated to maximise cerebral perfusion. A sharp rise in CPP may result in a rising ICP, a fall in CPP may result in cerebral ischaemia. It may be calculated by the following equation:
MAP
1/3 SBP+ 2/3 DBP
What is the normal intracranial pressure?
The normal intracranial pressure is between 7 and 15 mm Hg. The brain can accommodate increases up to 24 mm Hg, thereafter clinical features will become evident.
Which main group of receptors does dobutamine bind to?
Inotrope Cardiovascular receptor action Adrenaline α-1, α-2, β-1, β-2 Noradrenaline α-1,( α-2), (β-1), (β-2) Dobutamine β-1, (β 2) Dopamine (α-1), (α-2), (β-1), D-1,D-2
Effects of adrenergig receptor binding
α-1, α-2 vasoconstriction β-1 increased cardiac contractility and HR β-2 vasodilatation D-1 renal and spleen vasodilatation D-2 inhibits release of noradrenaline
Factors stimulating renin secretion
Hypotension causing reduced renal perfusion Hyponatraemia Sympathetic nerve stimulation Catecholamines Erect posture
Factors reducing renin secretion
Drugs: beta-blockers, NSAIDs
What do parietal cells secrete
what to chief cells secrete
what to mucosal cells secrete
Chief of Pepsi cola = Chief cells secrete PEPSInogen
Parietal cells: secrete HCl, Ca, Na, Mg and intrinsic factor
Chief cells: secrete pepsinogen
Surface mucosal cells: secrete mucus and bicarbonate
IV Pamidronate
Calcium > 3.5 mmol/l
Urgent management of hyperCa is indicated if:
Calcium > 3.5 mmol/l
Reduced consciousness
Severe abdominal pain
Pre renal failure
At what site is most dietary iron absorbed?
Iron is best absorbed from the proximal small bowel (duodenum and jejunum) in the Fe 2+ state.
Felty’s syndrome
heumatoid arthritis (RA), an enlarged spleen (splenomegaly) and a decreased white blood cell count (neutropenia)
Stimulation of insulin release:
Glucose Amino acid Vagal cholinergic Secretin/Gastrin/CCK Fatty acids Beta adrenergic drugs
Which of factors are sensitive to temperature
Factors V and VIII are sensitive to temperature which is the reason why FFP is frozen soon after collection.
Where does spironolactone act in the kidney?
Spironolactone is an aldosterone antagonist which acts at in the distal convoluted tubule.
The acute phase response includes:
acute phase proteins Reduction of transport proteins (albumin, transferrin) Hepatic sequestration cations Pyrexia Neutrophil leucocytosis Increased muscle proteolysis Changes in vascular permeability
Relative Glucocorticoid activity:
hydrocortisone
prednisolone
dexamethasone
Relative Glucocorticoid activity:
Hydrocortisone = 1 Prednisolone = 4 Dexamethasone = 25
excess glucocorticoids side effects
Thinning of the skin, osteonecrosis and osteoporosis are all common. Steroids are associated with retention of sodium and water. Potassium loss may occur and hypokalaemic alkalosis has been reported. ctions Glycogenolysis Gluconeogenesis Protein catabolism Lipolysis Stress response Anti-inflammatory Decrease protein in bones Increase gastric acid Increases neutrophils/platelets/red blood cells Inhibits fibroblastic activity
Causes of scapula winging
Winging of Scapula occurs in
- long thoracic nerve injury (most common)
- or from spinal accessory nerve injury (which denervates the trapezius)
- or a dorsal scapular nerve injury
Long thoracic nerve
Derived from ventral rami of C5, C6, and C7 (close to their emergence from intervertebral foramina)
It runs downward and passes either anterior or posterior to the middle scalene muscle
It reaches upper tip of serratus anterior muscle and descends on outer surface of this muscle, giving branches into it
Extra peritoneal rectum
Posterior upper third
Posterior and lateral middle third
Whole lower third
Arterial supply to rectum
Superior rectal artery
Middle rectal artery (from the internal iliac)
Inferior rectal artery (from the pudendal vessels)
Venous drainage of rectum
Superior rectal vein
Inferior rectal vein
Note the venous drainage is a site of portosystemic anastomosis.
Lymphatic drainage rectum
Mesorectal lymph nodes (superior to dentate line) Inguinal nodes (inferior to dentate line)
Inferior vena cava tributaries
Mnemonic for these: : I Like To Rise So High Iliacs Lumbar Testicular Renal Suprarenal Hepatic vein
Pathway of the IVC
Left and right common iliac veins merge to form the IVC. (L5)
Passes right of midline
Paired segmental lumbar veins drain into the IVC throughout its length
The right gonadal vein empties directly into the cava and the left gonadal vein generally empties into the left renal vein.
The next major veins are the renal veins and the hepatic veins
Pierces the central tendon of diaphragm at T8
Right atrium
Relations of IVC
Anteriorly:
small bowel, first and third part of duodenum, head of pancreas, liver and bile duct, right common iliac artery, right gonadal artery
Posteriorly:
Right renal artery, right psoas, right sympathetic chain, coeliac ganglion
Inferior vena cava tributaries and their levels
T8 Hepatic vein, inferior phrenic vein, pierces diaphragm L1 Right suprarenal vein, renal vein L2 Gonadal vein L1-5 Lumbar veins L5 Common iliac vein, formation of IVC
radial nerve course
The radial nerve runs in its groove on between the two heads (lateral and medial head of triceps muscle)
The ulnar nerve lies
anterior to the medial head of triceps
axillary nerve
The axillary nerve passes through the quadrangular space. This lies superior to lateral head of the triceps muscle and thus the lateral border of the quadrangular space is the humerus.
Triceps muscle - Origin
Has 3 heads - long, lateral and medial.
Origins of each
Long head- infraglenoid tubercle of the scapula.
Lateral head- dorsal surface of the humerus, lateral and proximal to the groove of the radial nerve
Medial head- posterior surface of the humerus on the inferomedial side of the radial groove and both of the intermuscular septae
Triceps- insertion
Olecranon process of the ulna.
Here the olecranon bursa is between the triceps tendon and olecranon.
Some fibres insert to the deep fascia of the forearm, posterior capsule of the elbow (preventing the capsule from being trapped between olecranon and olecranon fossa during extension)
Triceps muscle inntervation
Innervation - radial nerve
Triceps blood supply
Blood supply - profunda brachii artery
triceps action
Action
Elbow extension. The long head can adduct the humerus and extend it from a flexed position
Triceps Relations
The radial nerve and profunda brachii vessels lie between the lateral and medial heads
Vertebral column. how many at each level
There are 7 cervical, 12 thoracic, 5 lumbar, and 5 sacral vertebrae.
Spinal cord relative levels in respect to the vertebrae
The spinal cord segmental levels do not necessarily correspond to the vertebral segments.
C1 cord is located at the C1 vertebra
C8 cord is situated at the C7 vertebra
T1 cord is situated at the T1 vertebra
T12 cord is situated at the T8 vertebra.
The lumbar cord is situated between T9 and T11
The sacral cord is situated between the T12 to L2 vertebrae.
The spinal cord is approximately 45cm in men and 43cm in women. The denticulate ligament is a continuation of the pia mater (innermost covering of the spinal cord) which has intermittent lateral projections attaching the spinal cord to the dura mater
Cervical vertebrae
The interface between C1-2 atlanto-axis junction.
The C3 cord contains the phrenic nucleus.
Muscles and nerve root values of C spine
Muscle Nerve root value Deltoid C5,6 Biceps C5,6 Wrist extensors C6-8 Triceps C6-8 Wrist flexors C6-T1 Hand muscles C8-T1
Thoracic vertebrae
The thoracic vertebral segments are defined by those that have a rib. The spinal roots form the intercostal nerves that run on the bottom side of the ribs and these nerves control the intercostal muscles and associated dermatomes.
Lumbosacral vertebrae
Form the remainder of the segments below the vertebrae of the thorax. The lumbosacral spinal cord, however, starts at about T9 and continues only to L2. It contains most of the segments that innervate the hip and legs, as well as the buttocks and anal regions.
Cauda Equina
The spinal cord ends at L1-L2 vertebral level. The tip of the spinal cord is called the conus. Below the conus, there is a spray of spinal roots that is called the cauda equina. Injuries below L2 represent injuries to spinal roots rather than the spinal cord proper.
Structures within the right atrium
Musculi pectinati
Crista terminalis
Opening of the coronary sinus
Fossa ovalis
Cranial nerves carrying parasympathetic fibres
X IX VII III (1973)
III (oculomotor) Pupillary constriction and accommodation
VII (facial) Lacrimal gland, submandibular and sublingual glands
IX (glossopharyngeal) Parotid
X (vagus) Heart and abdominal viscera
Oesophagus
how long?
start and end?
covering?
25cm long
Starts at C6 vertebra, pierces diaphragm at T10 and ends at T11
Squamous epithelium
What are the constrictions of the oesophagus and how far are they from the incisors?
Structure Distance from incisors Cricoid cartilage 15cm Arch of the Aorta 22.5cm Left principal bronchus 27cm Diaphragmatic hiatus 40cm
Arterial supply to the oesophagus
Arteriarl supplies to oesophagus
Upper third Inferior thyroid
Mid third Aortic branches
Lower third Left gastric
venous drainage oesophagus
Veins
Upper third Inferior thyroid
Mid third Azygos branches
Lower third Left gastric
oesophagus lymphatic drainage
Upper third - deep cervical
Middle third - mediastinal
Lower third - gastric
Oesophagus nerv. supply
Upper half is supplied by the recurrent laryngeal nerve
Lower half by oesophageal plexus (vagus)
Histology oesophagus
Mucosa :Non-keratinized stratified squamous epithelium
Submucosa: glandular tissue
Muscularis externa (muscularis): composition varies. upper third - striated muscle, middle third - striated and smooth, lower third - smooth muscle
Adventitia
Superior mesenteric artery
start and how far does it supply
Branches off aorta at L1
Supplies small bowel from duodenum (distal to ampulla of vater) through to mid transverse colon
Takes more oblique angle from aorta and thus more likely to recieve emboli than coeliac axis
Relations of superior mesenteric artery
Superiorly: Neck of pancreas
Postero-inferiorly: Third part of duodenum Uncinate process
Posteriorly: Left renal vein
Right: Superior mesenteric vein
Branches of the superior mesenteric artery
Inferior pancreatico-duodenal artery (SMA passes under the neck of the pancreas prior to giving its first branch the inferior pancreatico-duodenal artery) Jejunal and ileal arcades Ileo-colic artery Right colic artery Middle colic artery
The structures passing behind the medial malleolus
from anterior to posterior include: tibialis posterior, flexor digitorum longus, posterior tibial vein, posterior tibial artery, nerve, flexor hallucis longus.
Ankle joint
The ankle joint is a synovial joint composed of the tibia and fibula superiorly and the talus inferiorly. Movements at the ankle joint Plantar flexion (55 degrees) Dorsiflexion (35 degrees) Inversion and eversion movements occur at the level of the sub talar joint
