Previous exam 2006 Flashcards
What are levels of evidence
Level of Evidence A: data derived from multiple randomized clinical trials of meta-analyses
Level of Evidence B: data from a single randomized trial, or nonrandomized studies
Level of Evidence C: only consensus opinion of experts, cases studies, or standard-of-care.
Female with right heart dysfunction now post op MVR with PA pressures 85/50. What are 4 specific interventions you would do
Principles:
Optimize preload
Minimize afterload (particulary the RV)
4 specific interventions
Administer fluid for PCWP 15 to 20
Nitroglycerine/nitroprussed for afterload reduction
Mirinone for reduction of PAP, inotropy, lusitropy
Inhaled nitric oxide
optimize O2/pH/Co2
Patient with RCA infarction post CABG–cannot wean from RVAD. List 3 possible recovery pathways
Bridge to recovery
Long-term VAD
Bridge to transplant
What is a protocol for weaning off RVAD
Start to wean when CI > 2.9 and no increase in PCWP when flow rate dropped by 50%. Then drop 25% further and assess PCWP.
How do you calculate pulmonary vascular resistnace
Mean PA pressure - LA pressure divuded by CO
measures in Dynes.
What degree of PVR do you intervene
PVR > 80 do not repair
PVR 6 to 8 do vasodilatory challenge
PVR < 6 then it’s ok
LVAD placement, output falls 12 hours after surgery: Give 4 possible cuases
Bleeding as a result of tamponade
RV failure
Device failure
Hypovolemia
4 clinical features of tamponade
Hypotension
Tachycardia
Low urine output
cold peripheral
4 hemodynamic features of tamponade
increased filling pressures equalization of filling pressures pulsus paradoxus low cardiac output Right atrium and right ventricular increased JVP respiratory variation in TV/MV inflow CVO tracing: attenuated y descent (reduced atrial filling) with or without prominent x
List 5 ways to assess athersclerosis of the aorta
Palpatin chest x-ray aortogram CT chest TEE Epiaortic echo
5 ways of dealing with porcelain aorta identified in the OR
cancel the case
Off pump LITA, RITA, with SVG with prximal contructed to LITA or innominate artery
Off pump beating assisted (cannulate femorial or axillary artery) and use off pump technique
Fibrillatory arrest–provided no AI
May perform only LIMA to LAD and do PCI to remainder
Replacing the ascending aorta under circulatory arrest and then do CABG
For off pump CABG lsit 3 things that are equivocal and list 5 things that are less with OPCABG
3 things that are equivocal 30 day mortality stroke rate myocardial infarction 5 things that are less with OPCABG post op AF red cell transfusion less inotropes length of stay few distalas
3 advantages of bicaval anastomosis in transplant
Less TR and MR
Less atrial arrhythmias and conduction disturbance
shorter hospital stay
reduced postoperative dependence on diuretics
Less RV dysfunction
List 6 clinical bedside test
No response to pain apnea absecene of brain stem reflexes (doll's eyes, caloric reflex test, pupils dilated) Bedside ECG sensory evoked potentials ensure no metabolic disturbances, pharmacologic agents, and hypothermia cerebral angiography radionuclide cortical blood flow studies
10 complications of open PDA ligation
recurrent laryngeal nerve damage chylothorax pnneumothorax hemothorax coarctatoin phrenic nerve injury ligation of PA, aorta residual flow rupture/hemorrhage infection death embolization
What is management of intra mural hematoma from LSCA to diaphragm;
IMH secondary to rupture of the vasa vasorum
Treat like type B dissection (BP control, operation for complication of type B such as contained rupture, malperfusion, progressive enlargement, persistent pain, and persistent hypetension
List 3 general physiologic derangements that can lead to tissue hypoxia and give an example of each
Low cardiac output (decrease deliver)
Anemia (decrease oxygen carrying capacity)
Hypoxemia: DO2 = Co x Hg x Sao2 + paO2
List 5 ways to repair the anterior leaflet of the mitral valve
triangular resection chordal transfer neochordiae alfieri stitch papillary muscle sliding or shortening chordal transpositoin from posterior leaflet
What is Custodiol cardioplegia
Intra-cellular solution
Crystalloid cardioplegia that contains histidine, trptophan, and ketoglutarate
histidine has a strong buffer effect which can prevent acidosis in cardiac myocytes
Low acting (2.5 hours)
30cc/kg in a single dose
Left superior vena cava and mitral surgery
What structure does NOT involute with persistent LSVC
What can be absent with persisten LSVC
Where does it drain
List 2 ways to do venous cannulation
Does not involute—Left anterior cardinal vein
The innominate vein maybe absent
Drains into coronary sinus
Venous cannulation: LSVC, double cannulation on the right if no innominate, cannulate coronary sinus with big cannula and do vaccum assit
Redo CABG–retrograde ongoing for 2 minutes–heart still beating. retrograde pressure is 40 with a flow of 60ml/min. What are two problems and how to correct
Problem # 1: Heart is still beating
Problem # 2: retrograde pressure is too low…should be 200ml/min. Could represent coroanry sinus becoming distended or that the cannula has entered the coronary vein.
Ways to solve this problem
Pull Canula back, increase flow, check K+, isolate and clamp lita, cool to 25 degrees C.
Patient is post CAB. 4 different medication and rationale
ASA–benefit on graft occlusion–Mangaon NEJM 2002 (lower MI, mortality, lower stroke, lower renal failure, bowel infarction)
Cholesterol lowering agent: decrease risk of CV events at > 7 years “post CABG NEJM 1997)
Beta Blocker: significant decrease in AF
ACE: Apres, IMAGINE–lower incidence of CV events, angina, repeat revascularization
FInish implanting a DDD pacemaker–nurses notices pt HR is 120 upper limit of device. List 3 possible causes
Pts own sinus rate at 120 (and device is at its upper limit)
Pt is in SVT (AF or A flutter)
Pacemaker-mediated tachycardia
What is Pacemaker-mediated tachycardia
Occurs with DDD pacemakers–inadvertently cause a reentrant arrhythmia. retrograde conduction through the AV node, possibly triggered by a premature ventricular depolarization.
If pacemaker senses the resulting atrial depolarization and paces the ventricle, a recurring cycle us set up that could continue indefinetly at the upper rate limit of the pacemaker.
