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
-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
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
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