Respiratory | Compliance & Elasticity — Transcript

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1. 0:07all engineers in this video we're going
2. 0:09to talk about compliance so first off
3. 0:12how we Define compliance well we have a
4. 0:15mathematical definition of compliance
5. 0:16and I'm just going to give you a kind of
6. 0:18like a a a simple term of compliance
7. 0:20let's write compliance right down here
8. 0:22so what is compliance compliance is
9. 0:25defined
10. 0:27as the change
11. 0:30and volume in this Cas we're talking
12. 0:32about the lungs or the chest wall right
13. 0:34so compliance could be for again it
14. 0:36could be for the actual
15. 0:38lungs or it could be for the chess wall
16. 0:40and we'll talk about both of
17. 0:42these so compliance is equal to the
18. 0:45change in volume of the lungs over the
19. 0:49change in the pressure okay but simply
20. 0:52when we talk about compliance compliance
21. 0:54is a measure of stretchability or
22. 0:56distensibility in other words if I want
23. 0:59to stretch something something and it
24. 1:01stretches very easily you know like a
25. 1:03rubber band or something like that
26. 1:04stretches very easily okay something
27. 1:06like that is very compliant our lungs
28. 1:08are naturally very compliant but at the
29. 1:10same time they have the opposite of that
30. 1:13they have just the right amount of
31. 1:15elasticity so in order for us to talk
32. 1:17about compliance we have to compare
33. 1:18compliance to another term which is
34. 1:21referred to as elasticity because
35. 1:23compliance is the it's another way of of
36. 1:26explaining is it's the ease at which you
37. 1:28stretch something it's how easy it is is
38. 1:30to stretch it where elasticity is the
39. 1:34resistance to the stretch it wants to
40. 1:36recoil assume the smallest SI possible
41. 1:38so
42. 1:39elasticity and again there is the
43. 1:41elasticity of the same thing the lungs
44. 1:45as well as the chess
45. 1:47wall but this situation is opposite it's
46. 1:52dependent upon the change in pressure
47. 1:54over the change in volume and we'll
48. 1:56explain what we mean by these formulas
49. 1:58here let's do that before we go into all
50. 2:01of these examples in which compliance
51. 2:04can actually vary in certain scenarios
52. 2:07so if we talk about compliance first
53. 2:10let's see how we can compare the
54. 2:11situation with volume okay change in
55. 2:13volume to compliance and the change in
56. 2:15pressure to compliance all right so
57. 2:17first things
58. 2:18first how would we say that volume is
59. 2:22affecting compliance it's simple they're
60. 2:25directly proportional so we can say from
61. 2:27this formula that the change in volume
62. 2:30is directly proportional to the
63. 2:32compliance whether it be the compliance
64. 2:34of the lungs or whether it be the
65. 2:35compliance of the chest wall whereas if
66. 2:39we increase pressure what happens to the
67. 2:40compliance it decreases so the change in
68. 2:43pressure is inversely proportional to
69. 2:46the compliance in other words if we
70. 2:48increase the pressure it decreases the
71. 2:50compliance if we decrease the pressure
72. 2:51it increases the compliance and we'll
73. 2:53talk about what this pressure is because
74. 2:55technically if if I were to rewrite this
75. 2:57this pressure here if we're talking
76. 2:59about the lungs actually we'll talk
77. 3:00about in a little bit because if it's in
78. 3:02the lungs it's the transpulmonary if
79. 3:04it's across the chest wall it's trans
80. 3:05thoracic we'll write that down now let's
81. 3:07write that down here so if it's for the
82. 3:09lungs it's transpulmonary we'll actually
83. 3:12go and show examples of this but if it's
84. 3:14the chest wall it's the trans thoracic
85. 3:16pressure if you remember TTP we denoted
86. 3:18it same thing for this for the lungs the
87. 3:20pre change in pressure is the
88. 3:22transpulmonary pressure the TP and the
89. 3:25chest wall which is going to be TTP
90. 3:30okay now elasticity look at the
91. 3:33relationship here any increase in the
92. 3:36pressure any change in the Inc any
93. 3:38change in the pressure upon which it's
94. 3:40increasing is directly proportional to
95. 3:42the
96. 3:44elasticity so in other words if you
97. 3:46increase the change in the pressure you
98. 3:48increase the actual elasticity whereas
99. 3:51if you change the
100. 3:54volume if I try to stretch something I'm
101. 3:56increasing the volume what does that do
102. 3:58to the elasticity it DEC increases it so
103. 4:00these are inversely proportional so I
104. 4:03just really wanted to make sure that we
105. 4:05differentiate the term compliance from
106. 4:07elasticity because they are not the same
107. 4:08term they're not of the same thing
108. 4:11they're exactly
109. 4:13opposites okay now what I want to do is
110. 4:16I want to talk about what is affecting
111. 4:19compliance in the lungs so what's
112. 4:21actually maintaining this normal
113. 4:23compliance within the lungs and then
114. 4:25what we'll do after that so what's the
115. 4:26first thing I want us to do first thing
116. 4:28I want us to do
117. 4:30in this video is talk about what things
118. 4:32are affecting compliance normally so
119. 4:35what
120. 4:38affects
121. 4:40compliance normally that's the first
122. 4:42thing I want to
123. 4:44do okay then the second thing that I
124. 4:48want to do is I want to go ahead and
125. 4:51relate these changes and volumes and
126. 4:53changes and pressures with real life
127. 4:54examples to compliance so then we're
128. 4:57going to compare
129. 5:00Delta V which is the change in volume
130. 5:02and then Delta P which is the change in
131. 5:04pressure to
132. 5:08compliance and then we'll throw in there
133. 5:09some clinical comp correlations with
134. 5:11that okay so let's go ahead and start
135. 5:13that so first thing what is affecting
136. 5:15compliance normally okay there's three
137. 5:18main things that are affecting
138. 5:19compliance I want you to remember these
139. 5:21so three main things affecting
140. 5:23compliance here look at
141. 5:25this here three main things affecting
142. 5:28compliance first first thing is
143. 5:30elasticity of the
144. 5:32lungs this is one thing that is actually
145. 5:34affecting compliance the elasticity of
146. 5:38the lungs second thing that's affecting
147. 5:40compliance is the surface tension we've
148. 5:44talked about this a couple times it's
149. 5:46that tension that's developed in the
150. 5:48alvioli of the lungs right between the
151. 5:51air and the water interface it's trying
152. 5:53to shrink the alveoli trying to make the
153. 5:54alveoli
154. 5:56collapse and the third thing that's
155. 5:58affecting compliance is is the
156. 6:02elasticity of the chest
157. 6:05wall
158. 6:07okay so let's explain what each one of
159. 6:09these things is actually trying to do so
160. 6:12let's first start off with the
161. 6:13elasticity of the lungs now our lungs
162. 6:17are they can stretch but they naturally
163. 6:19want to snap back but there's just the
164. 6:23right amount so in our lungs you know
165. 6:25there's different types of tissues
166. 6:27within our lungs but in general
167. 6:30our lungs are generally very compliant
168. 6:33they're very compliant but they also
169. 6:36have just the right amount of elasticity
170. 6:38so they're very compliant but they have
171. 6:40just the right amount of elasticity just
172. 6:43the right
173. 6:44amount so what do I mean by
174. 6:48this the lungs can actually expand with
175. 6:51ease okay they can expand with ease we
176. 6:53have to utilize some skeleton muscle to
177. 6:54assist in that process but they can
178. 6:56easily expand but they also want to
179. 6:58recoil let's say for example though that
180. 7:02I Chang the elasticity so right now the
181. 7:04compliance with of the lung so the
182. 7:07compliance of the lung is pretty much
183. 7:11equal to the
184. 7:12elasticity okay they're in just a nice
185. 7:15interplay there nice interplay let's say
186. 7:18that I changed the situation up let's
187. 7:20say I actually make the lung more
188. 7:22elastic how can I make the more L more
189. 7:24elastic well I prevent it from wanting
190. 7:26to stretch okay that's how I do it I
191. 7:28prevent it from wanting to stretch how
192. 7:30do we know that because we did the
193. 7:31formula we said that what in the formula
194. 7:33in the formula we said that if you
195. 7:34actually decrease the volume in other
196. 7:37words you you just don't allow for the
197. 7:38lung to stretch as much it'll actually
198. 7:40do what if you decrease the volume it'll
199. 7:42increase the elasticity right or vice
200. 7:45versa increase if you want to increase
201. 7:46the elasticity you actually do what
202. 7:48decrease the volume so it's not going to
203. 7:50want to stretch in this situation let's
204. 7:53say that I have I you know the person
205. 7:55unfortunately has what's called uh
206. 7:58pulmonary fibros is right so they have
207. 8:01pulmonary fibrosis in other
208. 8:04words let's say here is actually um over
209. 8:07here let's say over
210. 8:08here you have this person's lung right
211. 8:11they have just the right amount of
212. 8:12elastic tissue but now I'm going to do
213. 8:15this in like this brownish color this
214. 8:17brownish color is to represent fibrous
215. 8:19tissue so let's say that if someone's
216. 8:21getting older or they have certain type
217. 8:22of situation they're developing a lot of
218. 8:24fibrous tissue and a lot of fibrous
219. 8:27tissue is developing all around the
220. 8:28lungs as this starts developing a lot of
221. 8:31fibrous tissue what's the whole point of
222. 8:33this well fibrous tissue is not
223. 8:36distensible it doesn't like to be
224. 8:39stretched so if you actually have a lot
225. 8:40of fibrous tissue deposits here instead
226. 8:43of normal healthy lung tissue so a lot
227. 8:46of scar tissue fibrous tissue is really
228. 8:47scar tissue so let's say this is a lot
229. 8:49of scar
230. 8:50tissue which is the pulmonary fibrosis
231. 8:53that we said here a lot of scar tissue
232. 8:55formation it's not distensible so if it
233. 8:57doesn't want to stretch what happens to
234. 8:59the compliance the compliance decreases
235. 9:02but the elasticity increases okay so if
236. 9:06there is ponary fibrosis a lot of scar
237. 9:09tissue formation okay that fibrous
238. 9:11tissue accumulation it's not going to
239. 9:13want to stretch so what happens to the
240. 9:15elasticity now the elasticity goes up
241. 9:17and the compliance decreases so let's
242. 9:19write that here we'll do with color
243. 9:20coordinator right so in this situation
244. 9:24compliance is actually going to what
245. 9:27decrease and then what happens to the
246. 9:28elasticity the
247. 9:31elasticity increases and what's the
248. 9:33overall effect on the lungs the lungs
249. 9:35will not want to expand or they'll want
250. 9:36to recoil constantly so they're going to
251. 9:38have a hard time being able to be
252. 9:39inflated this is an example of some type
253. 9:41of restrictive pulmonary disorder where
254. 9:43they have a low Force vital
255. 9:45capacity let's take the opposite now
256. 9:47let's say that we actually make the long
257. 9:49super compliant okay now we take the
258. 9:52opposite let's say that I break down a
259. 9:55lot of that elastic tissue there so
260. 9:56let's say that we use the example here
261. 9:59of uh you know there's a disease called
262. 10:02osma so there's a disease here called
263. 10:07osma and osma is a disease you know in
264. 10:11the alvioli they have a lot of um this
265. 10:14pink tissue here a lot of these actual
266. 10:16they're very you know normal alviola
267. 10:18have a large surface area normal healthy
268. 10:20alviola have a large surface area so
269. 10:23that's one really important thing about
270. 10:24alveola is they have a large surface
271. 10:27area but with osma those neutrophils
272. 10:30start reling a lot a lot of elastase
273. 10:31enzymes and anti-alpha 1 antirion ISM
274. 10:34preventing it and what starts happening
275. 10:36they start breaking down a lot of that
276. 10:37elastic tissue as you start breaking
277. 10:40down a lot of that elastic tissue what's
278. 10:42going to happen to the lungs well now
279. 10:44they're not going to have as much
280. 10:45elasticity if they don't have as much
281. 10:47elasticity then what does that mean well
282. 10:49if their elasticity is decreasing what
283. 10:51do we say elasticity okay let's go back
284. 10:53to the formula we said that this is
285. 10:57inversely proportional so elasticity
286. 10:59decreases what happens to the volume it
287. 11:01increases huh well I thought if volume
288. 11:04increases compliance increases it does
289. 11:06you see how it's not that bad if we use
290. 11:08the formulas they can help us to really
291. 11:10understand this so in this situation in
292. 11:11actually empyema a chronic obstructive
293. 11:13pulmonary disorder the lungs are very
294. 11:16floppy so they're they're not very
295. 11:18compliant so in other words you can take
296. 11:20a lot of air in it's easy for these
297. 11:21individuals to take a lot of air in
298. 11:23generally but the problem is is what
299. 11:25does elasticity lungs allow for
300. 11:27expiration passively right so because of
301. 11:29that when the lungs collapse they help
302. 11:30to be able to push the air out passively
303. 11:32without having to put a lot of work into
304. 11:33it but in these individuals they're not
305. 11:35very actually elastic they're very
306. 11:37compliant and so their elasticity is
307. 11:39very less so they have very little
308. 11:41elasticity so the lungs aren't going to
309. 11:43snap back as well and so they're going
310. 11:45to have a hard time being able to get
311. 11:46air out so they have a low forced
312. 11:48expiratory volume so in this situation
313. 11:50we take the opposite so what happens to
314. 11:52their compliance their compliance
315. 11:56goes up and their elasticity goes
316. 12:01down not too bad so now that we've done
317. 12:04elasticity of the lungs let's do the
318. 12:06elasticity of the chest walls just stick
319. 12:07with this concept here okay and after we
320. 12:09do surface tension I'm going to talk
321. 12:10about pressure too how pressure affects
322. 12:13these
323. 12:14things okay so let's do this one in
324. 12:17purple let's do this one in purple so
325. 12:20let's say we talk about the chess wall
326. 12:23okay chess wall again same thing chess
327. 12:27wall is generally very compliant and
328. 12:29what do we say about the lungs lungs
329. 12:30generally have an inward recoil right
330. 12:33they want to they want to snap again we
331. 12:35said it like this right if we showed the
332. 12:37arrow it always wants to snap in like
333. 12:39this whereas the chest wall wants to
334. 12:41have a outward recoil right it likes to
335. 12:44be stretched outwards that's what helps
336. 12:45to keep this int plural pressure nice
337. 12:47and
338. 12:48negative well on this say this situation
339. 12:50there's a nice interplay between the
340. 12:52chest wall elasticity right and the
341. 12:53chest wall compliance so there's just
342. 12:55it's like you know we said again
343. 12:57compliance
344. 12:59of the chest wall is just enough that
345. 13:01there's not any type of situation where
346. 13:04there's one overcoming the other it's
347. 13:06just the right amount in Norm normal
348. 13:08healthy individuals where there there
349. 13:10this this nice dynamic dynamic and we
350. 13:13need to make sure that we say this
351. 13:14because it's not always perfect there's
352. 13:16this kind of pull pull pull one side but
353. 13:19it's always trying to keep it in
354. 13:20equilibrium so there's a dynamic
355. 13:23interplay between these two to maintain
356. 13:26the natural compliance and elasticity
357. 13:28but again
358. 13:30let's understand this in pathological
359. 13:33conditions or just in different types of
360. 13:34physiological
361. 13:35situations let's say that this person
362. 13:40their chest wall I let's say that they
363. 13:43have ankle loing spondilitis you know
364. 13:45there's a it's a situation it's an
365. 13:48inflammatory arthritis and in that
366. 13:50inflammatory arthritis they have like
367. 13:52kind of like a hunched over posture
368. 13:55right so in this situation which is
369. 13:57called ankal loing spondilitis
370. 14:01ankal loing spondilitis
371. 14:05or you know there's another one it's
372. 14:07called um kyphosis kyphosis when they
373. 14:10have that hunched over posture too their
374. 14:12their chest cavi is kind of like bent
375. 14:14over like that so they have kyphosis so
376. 14:16an individual we can even have what's
377. 14:18called kyphosis or even scoliosis too
378. 14:21and even scoliosis if you guys remember
379. 14:24scoliosis so kyphosis I like to remember
380. 14:26like this let's say here's the K here's
381. 14:29the
382. 14:30guys put the guy's head like this put
383. 14:33his feet right here and here's his arms
384. 14:36like that he's actually having a hunched
385. 14:39over posture so he has a hunched over
386. 14:40posture whereas scoliosis they have a
387. 14:43abnormally s-shaped spine right and
388. 14:46again here's the guy here's his arms
389. 14:48whatever you know just a little funny
390. 14:50diagram there so kyos is to have a
391. 14:52hunched over posture so does ankal loing
392. 14:54spondilitis and scoliosis you know what
393. 14:57else can happen in these individuals
394. 14:58let's say that there's another person no
395. 15:00abnormality you just get older you know
396. 15:02when we get older we get a little bit
397. 15:03more
398. 15:04decrepit our cartilage within the actual
399. 15:08ribs and stuff like that it starts to
400. 15:10get really really aifi and it doesn't
401. 15:12want to allow for stretching so if that
402. 15:14happens this can also affect the actual
403. 15:17stretching desire of the chest wall so
404. 15:20in certain situations in which as we get
405. 15:22older like the aify you aify
406. 15:26aify the actual uh cartilage the actual
407. 15:30cartilage around the ribs cartilage of
408. 15:32ribs and so it doesn't allow for it to
409. 15:35allow for that
410. 15:37expansion okay so anyway we got this one
411. 15:39anking spondilitis kyphosis scoliosis or
412. 15:41even oifc of the the cartilage of the
413. 15:43ribs what would that do to the
414. 15:46compliance okay if you're in this
415. 15:49hunched over position and you're stuck
416. 15:51like this are you I'm going to have a
417. 15:53hard time bringing air in so imagine me
418. 15:54trying to do that it's it's hard doing
419. 15:57it right here but then if I hunch back
420. 15:58over you know into normal position I can
421. 16:00take a decent amount of air in so
422. 16:02because of that they're going to these
423. 16:03people are going to have a really hard
424. 16:04time bringing air in so their compliance
425. 16:06is going to decrease because their chest
426. 16:07wall is not very good at being able to
427. 16:10have that nice distensibility so because
428. 16:13of that the compliance of their chest
429. 16:14wall
430. 16:16decreases okay so these people have a
431. 16:19decrease
432. 16:22compliance of the chest
433. 16:25wall and in the opposite of that because
434. 16:29of them maybe having some oifc of the
435. 16:30cartilage or the ribs or these type of
436. 16:32situations they're stuck in that
437. 16:34position they don't they they have a
438. 16:36hard time being able to go they they're
439. 16:37back to that normal position they're
440. 16:39kind of stuck in that position so
441. 16:41because of that if you think about it
442. 16:43it's not necessarily that their
443. 16:44elasticity is actually increasing it's
444. 16:47really more that their chest wall just
445. 16:48doesn't have the ability to expand we
446. 16:50can say in a way that their elasticity
447. 16:52is increasing but we're not going to do
448. 16:54that here because more of the situation
449. 16:55here is that the compliance of their
450. 16:57chest wall is actually de increasing so
451. 16:59it doesn't want to actually stretch out
452. 17:01and expand to allow for the lungs to
453. 17:02fill with air and you can imagine if
454. 17:05there was some type of situation in
455. 17:06which the chest wall was very very
456. 17:09flexible right if the chest wall was
457. 17:11very very flexible for whatever reason
458. 17:13if the chest wall was very very actually
459. 17:15flexible and it can actually expand out
460. 17:17a lot then what does that mean that
461. 17:18means that the compliance goes up and if
462. 17:20the compliance of the chest wall goes up
463. 17:22what does that mean that means we can
464. 17:24actually inhale more air so it's that
465. 17:26simple right so not very very confusing
466. 17:30next one let's do surface tension so
467. 17:32surface tension and then we're going to
468. 17:33talk about pressure so we're going to go
469. 17:34a little bit more into these formulas
470. 17:36right after this so now let's talk about
471. 17:38surface tension let's do this one in
472. 17:40this nice blue color
473. 17:42here okay so the next one is surface
474. 17:46tension first off what is surface
475. 17:49tension we'll talk about this in more
476. 17:50detail in another video but surface
477. 17:52tension is basically whenever you take
478. 17:55like an alveoli let's say here's an
479. 17:57alveoli and you have this liquid you
480. 18:02have this actual water layer there's a
481. 18:04nice little water layer here that's
482. 18:06interacting with the air sometimes what
483. 18:08can happen is there can be a lot of
484. 18:10tension developed between the air and
485. 18:12the water interface and what this does
486. 18:15it tries to actually shrink the whole
487. 18:17purpose of is it tries to shrink the
488. 18:19alvioli and when it tries to shrink the
489. 18:21alveoli it tries to collapse the alveol
490. 18:22it wants to get to be as small as
491. 18:25possible well if you think about that
492. 18:28if alveoli are the basic like functional
493. 18:31unit and structural unit of our lungs
494. 18:33our lungs are made up of many of these
495. 18:36so if all of these alveoli start
496. 18:37shrinking what's going to happen to the
497. 18:39lungs they're all going to want to start
498. 18:41trying to be as small as
499. 18:44possible if they become very very small
500. 18:48what is that going to do then that's
501. 18:50going to be a lot
502. 18:51of lot of resistance against me trying
503. 18:54to bring air in you know there's a
504. 18:57situation that this can happen in
505. 18:58infants when they don't produce enough
506. 18:59of a a protein lipid complex called
507. 19:01surfact and we'll talk about it's called
508. 19:03infant respiratory distress syndrome and
509. 19:06what happens is because of that there's
510. 19:08so much surface tension that it takes so
511. 19:10much effort so much work to bring in as
512. 19:14much air as possible to inflate the
513. 19:16avoli so because of that if you imagine
514. 19:18if the surface tension is increasing
515. 19:22excessively in some type of situation
516. 19:25like we gave an example uh infant resp
517. 19:28respiratory distress syndrome where they
518. 19:31don't make a protein lipid complex
519. 19:33called surfactant what would this do to
520. 19:35the compliance it would decrease the
521. 19:37actual
522. 19:39compliance what would that mean for this
523. 19:41individual they would have a really
524. 19:44really hard time bringing air in they
525. 19:46would it would increase the workload of
526. 19:48breathing so what would it do what would
527. 19:49this decrease compliance do this would
528. 19:52decrease the I'm sorry not decrease the
529. 19:54workload this would increase the
530. 19:56workload of the breathing process so
531. 19:58this would incre increase the work of
532. 20:01breathing that's why these uh babies or
533. 20:04infants that have this situation you
534. 20:06usually have to put them on a mechanical
535. 20:07ventilator because they can't breathe on
536. 20:09their own they have a hard time being
537. 20:10able to inflate the alveoli and even
538. 20:12when they expire the alveoli collapse
539. 20:14and it takes so much effort to reinl
540. 20:16them so it's a terrible
541. 20:19situation but let's take the normal
542. 20:21situation so let's say that this is the
543. 20:23extreme what if you produce a protein
544. 20:25called surfactant you know there's a
545. 20:26protein lipid complex that that our type
546. 20:29two Alvar cells produce and the whole
547. 20:32purpose is that they try to decrease
548. 20:34this surface tension and when they try
549. 20:36to decrease the surface tension that
550. 20:38tries to decrease the desire of this
551. 20:39alveoli to collapse and when it prevents
552. 20:42this actual recoil it allows for the
553. 20:44alveoli to it then in instead of wanting
554. 20:46to recoil to allow for it to expand so
555. 20:49if we decrease the surface tension and
556. 20:51how could we do that how can we decrease
557. 20:53the surface tension we give you know you
558. 20:57have this person producing
559. 20:59normal amounts of
560. 21:03surfactant which is this protein lipid
561. 21:06complex and what that does is that
562. 21:07decreases the surface tension so if
563. 21:09that's the case then let's say I redraw
564. 21:10this
565. 21:11alveoli and again I put
566. 21:14here this is the liquid right here and
567. 21:17it's interacting with the air so there's
568. 21:19this air water interface and what's
569. 21:21happening is that you're trying to be
570. 21:23able
571. 21:24to decrease the surface tension so
572. 21:26what's going to happen now if you
573. 21:27decrease the surf surface tension
574. 21:29between the air water water interface
575. 21:30here's the air here's the water right
576. 21:33you're going to allow for this alveoli
577. 21:35to more likely be want to
578. 21:38expand and if the alveoli will want to
579. 21:40expand and not recoil what does that
580. 21:42mean for the lungs well again this is
581. 21:43the basic structal and functional unit
582. 21:45so if this wants to expand all of the
583. 21:48lung would want to expand and if the
584. 21:50lungs wants to expand what does that
585. 21:52mean for compliance that means the
586. 21:53compliance is increasing right and so so
587. 21:57compliance for this situation
588. 21:59could compliance should increase and
589. 22:02what does that mean for the workload it
590. 22:04decreases the actual work of
591. 22:09breathing man it's a beautiful thing
592. 22:13okay but now these are the three main
593. 22:17things that affects compliance
594. 22:20okay these are the things I really want
595. 22:22you to remember but if you really want
596. 22:24to be good at compliance you really want
597. 22:25to be able to remember other things that
598. 22:27really is important I want you to
599. 22:29remember two other
600. 22:31situations that is neuromuscular
601. 22:38problems okay so I want you to remember
602. 22:41this neuromuscular problem and this is
603. 22:44actually this is going to be the main
604. 22:46thing we'll just specifically talk about
605. 22:47this one one more uh thing that I want
606. 22:49to talk about neuromuscular problems
607. 22:51let's
608. 22:52say uh that you have a situation where
609. 22:55the
610. 22:56diaphragm is injured
611. 22:59if the diaphragm by some terrible
612. 23:01situation is injured and it's damaged
613. 23:06and it can't contract will it be able to
614. 23:07contribute to the inspiration process no
615. 23:10if the diaphragm is damaged will the
616. 23:11lungs be able to expand no so what does
617. 23:12that Doe to the compliance it decreases
618. 23:15compliance let's say by some situation
619. 23:17you paralyze your external intercostal
620. 23:19muscles if you paralyze the external
621. 23:21intercostal muscles what does that mean
622. 23:23for that that means that they can't lift
623. 23:24the ribs outward like the bucket handle
624. 23:26movement that means that they can't pull
625. 23:27the sternum outward like this like the
626. 23:29pump handle movement what does that mean
627. 23:31for the actual expansion of the lungs it
628. 23:33decreases so what does that mean for
629. 23:34compliance it decreases but that's the
630. 23:37muscles directly you know there's
631. 23:38another terrible condition remember this
632. 23:41was the
633. 23:42vrg and it was sending down these axons
634. 23:45into the actual anterior gray Horn of
635. 23:47the spinal cord you know there's a a
636. 23:50disease that damages some of these
637. 23:52neurons right here that come out and
638. 23:54Supply these
639. 23:56muscles okay look
640. 24:00this condition which can actually
641. 24:02destroy these actual neurons right here
642. 24:06these anterior um specifically in the
643. 24:08vental grey horn of the spinal cord they
644. 24:10call it ALS alss which stands for a
645. 24:15myotropic lateral sorosis right in that
646. 24:18situation in which someone has ALS it
647. 24:21destroys these neurons if these neurons
648. 24:23are destroyed will they be able to send
649. 24:24action potentials out to the diaphragm
650. 24:25no so the action potentials out to the
651. 24:27diaphragm are
652. 24:28decreased will the muscle be able to
653. 24:30contract no if it can't contract what
654. 24:32will that do to the actual compliance
655. 24:34it'll decrease the compliance same thing
656. 24:37here if you damage these actual vent
657. 24:39gray horn right the the sematic motor
658. 24:41neurons there the cell bodies they're
659. 24:42not going to be able to send muscles Ste
660. 24:44the ACT send impulses to the external
661. 24:45intercostals if that's the case these
662. 24:48muscles can't contract and they can't
663. 24:50Elevate the ribs and pull the actual
664. 24:52Stern them out and that would also
665. 24:53decrease
666. 24:55compliance last thing I want to talk
667. 24:57about is oh one last one more thing
668. 24:59before we finish this right here one
669. 25:01more thing that can also affect
670. 25:02compliance before we go in here and
671. 25:03explain these pressures and volumes a
672. 25:04little bit more is this situation here
673. 25:07let's say that someone
674. 25:08has mucus so they don't actually have
675. 25:11like you know let's say that we have a
676. 25:12situation here where they have a lot of
677. 25:14mucus building up here if you have a lot
678. 25:18of mucus building up inside of these
679. 25:20actual bronchi or bronchials or whatever
680. 25:22maybe due to chronic bronchitis or
681. 25:24cystic fibrosis whatever it might be
682. 25:26what happens to the air can the air get
683. 25:28in no all this air is prevented from
684. 25:30getting into the alveoli if you can't
685. 25:32get air into the alvioli what happens to
686. 25:34the AL alveoli they become
687. 25:36underventilated if they're
688. 25:38underventilated will the alvioli be able
689. 25:40to expand as well as the lungs be able
690. 25:42to expand no so if there's a lot of
691. 25:45mucus buildup what could that do a lot
692. 25:47of mucus buildup could also decrease the
693. 25:50compliance of the lungs all right so
694. 25:53what if I actually what if I poke a hole
695. 25:56what if I poke a hole
696. 25:58through the chest wall and into the
697. 26:01parietal plura and I open up the actual
698. 26:03plural cavity to the atmosphere let's
699. 26:06say that I do that let's say that
700. 26:07somehow I got stabbed it went through
701. 26:10the skin and you know went through the
702. 26:13actual muscle tissue and through this
703. 26:14connective tissue structures and it
704. 26:16penetrated and punctured a hole and it
705. 26:19opened up this space here look look at
706. 26:21this all that's open so now what was the
707. 26:25actual pressure in here what was this
708. 26:27pressure you guys remember this pressure
709. 26:29in the plural cavity it was called the
710. 26:31int plural pressure you know the int
711. 26:33plural pressure is normally uh closes uh
712. 26:36you know to about -4 millimeter mercury
713. 26:40and then what did we say the
714. 26:40intrapulmonary pressure was the
715. 26:41intrapulmonary pressure was a
716. 26:44proximately during this process right
717. 26:45it's about 0o millimeter of
718. 26:48mercury and then we said that the
719. 26:50pressure in the atmosphere was
720. 26:52approximately about 760 millimeter
721. 26:55mercury right because again these two
722. 26:57there's no change between this one and
723. 26:59this one is actually a 4 mm Mercury
724. 27:01difference so I could even rewrite this
725. 27:02one as 760 M MMG or 756
726. 27:06MMG but nonetheless look at
727. 27:08this look what happens the atmospheric
728. 27:12pressure is 760 how could I write this
729. 27:14one remember I said we could write it as
730. 27:16756 so let me write that as
731. 27:18756
732. 27:21756 millimet of
733. 27:24mercury look at the pressure radient
734. 27:26difference 760 mm Mercury to 756 what
735. 27:29does the diffusion principle say things
736. 27:31like to go from areas of high pressure
737. 27:32to areas of low pressure so where will
738. 27:34the air start flowing the air will start
739. 27:36flowing very very viciously and
740. 27:38vigorously into the actual plural cavity
741. 27:43as it starts accumulating within the
742. 27:44plural cavity what starts happening air
743. 27:46starts accumulating as air starts
744. 27:48accumulating into the plural cavity oh
745. 27:50what is that call what is that call
746. 27:51whenever air accumulates in the plal
747. 27:52cavity you know it's called numo
748. 27:54thorax it's called a numo thorax
749. 27:59what do you call it whenever there's
750. 28:00some type of infection you know there's
751. 28:01actually the capillaries here you have
752. 28:03the pulmonary capillaries and the
753. 28:05pulmonary capillaries are actually
754. 28:07supplying the alveoli let's say by some
755. 28:10situation there's some type of infection
756. 28:11or damage and some of the blood from
757. 28:14this actually leaks out here what is
758. 28:16that called what is that situation
759. 28:18called that situation right there is
760. 28:20called a
761. 28:25hemothorax anyway nonetheless a any type
762. 28:28of
763. 28:29situation in which air or blood or
764. 28:31different types of fluid is actually
765. 28:33accumulating inside of this actual
766. 28:36plural cavity what do you think it's
767. 28:38going to do to the int plural pressure
768. 28:40it's going to increase the int plural
769. 28:41pressure so as more air accumulates the
770. 28:43air is going to keep flowing in and
771. 28:45flowing in and flowing into this actual
772. 28:47plural cavity until the intop plural
773. 28:49pressure equalizes with the atmospheric
774. 28:51pressure what is the atmospheric
775. 28:53pressure 760 so what would the int
776. 28:55plural pressure become the int plural
777. 28:57pressure pressure will eventually have
778. 28:59keep receiving air until it equals
779. 29:01atmospheric pressure which is 760 mm
780. 29:04Mercury what is that in this terms -4
781. 29:06will go up to 0 millimet Mercury which
782. 29:10is 760 right now look at
783. 29:13this when the intal pressure the
784. 29:15pressure inside of this plural cavity
785. 29:17equalizes with the actual intrapulmonary
786. 29:19pressure even by some chance it becomes
787. 29:21even greater like plus one it's going to
788. 29:24start pushing on the actual lungs and as
789. 29:28it starts pushing and pushing and
790. 29:30pushing and pushing on the lungs
791. 29:31creating this actual Force what is it
792. 29:34going to try to do it's going to try to
793. 29:35collapse the lungs what would that do to
794. 29:36the compliance it would decrease the
795. 29:38compliance right so it's going to try to
796. 29:39collapse lung what ises that called
797. 29:40whenever you collapse the lung what is
798. 29:42lung collapse called whether it be numo
799. 29:44thorax or hemothorax or other different
800. 29:46types of situations any type of plural
801. 29:48affusion that's accumulating out there
802. 29:50this could introduce what's called atal
803. 29:52lactases right so
804. 29:55ATA lactases
805. 29:59okay so now if this is a lung collapse
806. 30:04right what is the lung trying to doing
807. 30:06it's trying to shrink if it's trying to
808. 30:08shrink what does that mean for
809. 30:09elasticity it's trying to actually snap
810. 30:11back right so in a way you can think
811. 30:12about if it's trying to be very elastic
812. 30:14if it's trying to be very elastic it
813. 30:15wants to snap back and become very very
814. 30:17small what does that Doe to the volume
815. 30:18of the lung well the volume of the lung
816. 30:20will start decreasing if the volume of
817. 30:23the lung starts decreasing what does
818. 30:24that mean for compliance if volume
819. 30:27decreases compliance decreases it's not
820. 30:30that bad
821. 30:32right all right so in this video we
822. 30:34talked a lot about compliance and
823. 30:36elasticity and we basically focused on
824. 30:38what what affects compliance normally
825. 30:41right we talked about elasticity the
826. 30:43lungs elas to chest wall surface tension
827. 30:46neuromuscular problems we compiled a
828. 30:49whole bunch of different types of uh
829. 30:51disorders or different types of
830. 30:52physiological conditions that can affect
831. 30:54it and then we even applied we compared
832. 30:57this whole ch CH in volume change in
833. 30:59pressure to compliance along all of
834. 31:00these examples right and then we even
835. 31:02threw in there a little pathological
836. 31:04condition called numo thorax and
837. 31:06hemothorax to compare it with adal
838. 31:08lactases all right all right Engineers I
839. 31:10hope all of this stuff made sense I hope
840. 31:11you guys did enjoy it if you did please
841. 31:13hit the like button comment down in the
842. 31:15comment section and please subscribe all
843. 31:16right Ninja nerds as always until next
844. 31:18time