Midterm 2 - Lecture 6 (Periopoerative PT) Flashcards
effects of anesthesia on respiratory function depends on what 3 things?
describe the american society of anesthesiologists’ physical status classification stratification of risks of mortality from anethetic (ASA class)
name the 6 perioperative PT effects of anesthesia
1) altered breathing pattern
2) decreased respiratory drive
3) decreased FRC
4) decreased lung compliance and increased resistance
5) depressed or abolished cough reflex
6) increased V/Q mismatch
how is the breathing pattern altered due to the effects of anethesia
- 1&2) Depends on depth of anethesia – as it deepens more rapid shallow breathing, very deep – gasping and completely irregular
- 4) Increase of dead space ventilation relative to tidal breathing (Vd/Vt)
- 5) Sigh improves oxygen to brain and helps stimulate surfactant production and maintain lung compliance (with decre. more risk of atelectesis (lung collapse), decreased oxygenation, etc)
how is resp drive altered due to the effects of anethesia
- Minute expiration
- Deeper anesthetic – ventilatory response supressed
how is FRC altered due to anesthesia? - what are the causes of this frc effect?
note: The closing capacity (CC) is the volume in the lungs at which its smallest airways, the respiratory bronchioles, collapse.
causes of decreased FRC:
- supine position during surgery (abd contents move up)
- reduced rib cage muscle tone
- increased abd muscle tone
- additional loss of muscle tone with muscle paralysis
- manipulation of the lung/diaphragm
how is lung compliance altered due to anethesia?
-Less surfactant produced = decr. Compliance
describe what happens to the cough reflex due to anesthesia
- Abolishes or suppresses cough reflex – if you have secretions need to cough after surgery (could be problematic) – so they don’t feel the need to cough even though they are congested – not good for clearance (will retain the fluid etc)
- As long as person is feeling “groggy” – they will have these anesthetic effects
describe how anesthesia affects V/Q matching
- 1) Bc intercostals not contributing as much – dpgm may or may not be intact etc
- 2) more redistribution of blood to areas if you have local problems – bit can anticipate there will be more shunting = mismatch
- 3) breathing very shallow/panting (not good for survival) – so assisted by being put on ventilator – even higher risk for mismatch – ventilates uppermost regions of lungs, not lower
what are the patient-related risk factors for perioperative PT?
A) People with congestive heart failure also at high risk (people with pulmonary edema)
DLCO = diffusing capacity of the lungs for CO2
B) Age is a predictor on its own, also FEV1 decr with age
C) –
D) would take 8 weeks prior to surgery to see effects of cilia damage reversed
E) kypho = restrictive
F) Obese = no increased risk in research as a result of their weight (even morbildy obese)
what are surgery related risk factors for perioperative PT?
1) type of surgery
2) prolonged operative procedures
what is the order of surgery riskiness - highest-lowest?
abdominal aortic aneurism > thoracic > upper abd (bc closer to diaphragm) > lower abd > non-abd/non-thoraccic
how does type of surgery affect perioperative PT risk factors
- Pdi = pressure of diaphrm
- Pushing dpgm up decreasing FRC etc
- Supine = bases of lung = dependent area
how do prolonged operative procedures affect risk factors?
what are some reasons for thoraccic surgery?
name the 5 types of surgical incisions
1) anterolateral thoracotomy
2) posterolateral thoracotomy
3) thoracoplasty
4) mediam sternotomy
5) thoracoabdominal incision
describe the anterolateral thoracotomy surgical approach
-Often afraid to move shoulder on that side for pts post-op – teahc them they need to try to move it so they don’t end up with frozen shoulder
describe the posterolateral thoracotomy surgical approach
describe the thoracoplasty approach to surgery
- For tx of tuberculosis – typically in apices of lung bc high oxygen there
- Causes a collapse of lung in that area bc of removal of ribs – lack of support from missing ribs therefore structural instability – cause lean away from surgury side
- Paradoxical breathing bc don’t have ribs there so sucking in on that side
- White area in xray = chest wall that is collapsed (ribs removed on right)
describe the mediam sternotomy surgical approach
- No muscles cut – only sternal aponeurosis cut
- Wire the chest together – visible on chest xray
describe the thoracoabdominal incision surgical approach
- Top right incision
- When you cut abd muscles - post operatively will be painful to cough
what is a lobectomy (what are diff types?)
Sleeve resection – removal of part of bronchus followed by end to end anastamosis
what is a segmental resection?
what is a wedge resection?
what is a pneumonectomy?
-Initially dpm rise and remaining structures shift into cavity but over time shifts back to position as cavity is filled and is more fibrotic
what is a pleurodectomy?
what is a pleurodesis?
what is a decortication?
what are the types of lung biopsy?
describe lung volume reduction surgery and what the outcomes are
explain how to do PT with a chest tube
what is the purpose of a chest tube? insertion site? conditions requiring one?
describe how the chest tube works
- Recall chest tube inserted above rib (due to nerve artery vein below rib)
- Tube (from patient) goes into trap bottle (left compartment) and another tube goes from this bottle to next bottle that has a fluid level – seals any air getting evacuated or preventing air from coming back into person chest
- Sometimes second compartment can have tube attached to suction source generating a negative pressure
- First bottle drains and traps fluid, second drains and traps air
- Exhale pushed air from pleural space goes to second compartment and leaves – insp prevents air from leaking back into pleural space (bottle seal)
- If you see bubbles forming in exhalation means they have an active leak (insp doesn’t bubble)
- If tube doesn’t bubble anymore – means leak has started to seal itself
- Chest tubes can come out when bubbles stop and can see on xray that lung has expanded
- Draining is passive due to negative positive pressures within the thorax (from normal breathing pattern)
what are 4 objectives of perioperative PT?
describe the preoperative tasks of PT
what are the goals of perioperative PT?
describe supported huffing and coughing
describe what can be done for postoperative treatment
what can be done postoperatively for pts with secretions?
- 1) helps to better ventilate lower lungs
- 3) modified – bc pts cant always lie on front etc
- 4) affected lung is up, unaffected down to optimize VQ matching – can always have them lying like this though bc even that lung can dvelop compression atelectesis – changing position is very important
what can be done postoperatively for thoracotomy pts?
-Not indicated to put in prone post op
-
- FOR Pneumonectomy – controversy – some drs wont want pt lying o operated side, sometimes they don’t want lying on unoperated side
- If on op side – drs think bc there is a cavity – increased tendancy for mediastinum to shift w gravity
- If on unoperated side - if there is a leak, could cause flooding on unaffected lung
- No good answer for which is better!
what are potential risk factors for atelectisis?
If you are just focusing on coughing for treatment and not inspiration – not good (atelectisis risk)
atecectesis - when does it occur - who is at risk?
Hypovent – due to pain (incisions etc)
Increaseed rate of breathing (decreased depth)
Hypocapnea could be seen
fiO2 = fraction of inspired oxygen
Even moreso risk post-operatively
