Chapter 102 - Compartment syndrome and its management

Question 1

Poiseuille’s Law

Answer 1

F = pi r^4 deltaP / 8nL F = capillary blood flow r = radius of capillary deltaP = pressure gradient pre-capillary arteriole to post-capillary venule

Question 2

Matson’s critical closing pressure theory

Answer 2

Capillaries collapse after this pressure Disproven by Hartsock

Question 3

Hartsock dynamic pressure ICP-MAP cutoff for likely capillary collapse

Answer 3

25.5 +/- 14 mmHg

Question 4

Dynamic intracompartmental pressure threshold for 1) healthy tissue 2) injured tissue

Answer 4

MAP - ICP 1) < 30 mmHg 2) < 40 mmHg

Question 5

Usual cutoff used for pressure threshold

Answer 5

MAP - ICP < 40 mmHg DBP - ICP < 10 mmHg

Question 6

Causes of compartment syndrome

Answer 6

1) ischemia reperfusion 2) trauma 3) venous outflow obstruction (needs extensive multilevel DVT) 4) hemorrhage 5) fractures 6) crush injuries 7) iatrogenic

Question 7

Mechanism of ischemia reperfusion leading to compartment syndrome

Answer 7

1) muscle injury 2) increase microvascular permeability 3) efflux of plasma protein 4) interstitial edema

Question 8

Papalambros risk factors of compartment after limb ischemia

Answer 8

1) prolonged > 6 houors 2) younger age 3) insufficienct collaterals 4) hypertension 5) acute course of occlusion 6) poor backbleeding from distal vessels

Question 9

Rate of fasciotomy after different type of vascular trauma

Answer 9

1) Arterial: 29.5% 2) Venous: 15.2% 3) Combined arterial + venous: 31.6% 4) Popliteal artery injury: 61%

Question 10

Rate of fracture-induced compartment syndrome

Answer 10

1-29%

Question 11

Risk factors associated with fractures that predispose compartment syndrome

Answer 11

1) anterior compartment of leg 2) flexor compartment of arm 3) communited fracture (means higher energy of injury)

Question 12

Mechanism that crush injuries cause compartment syndrome

Answer 12

1) direct muscle injury 2) ischemia reperfusion 3) large volume crystalloids

Question 13

Iatrogenic causes of compartment syndrome

Answer 13

1) extravasation of IV 2) bleeding 3) compression

Question 14

Secondary compartment syndrome define

Answer 14

1) no direct trauma 2) diffuse microvascular permeability due to trauma-induced SIRS 3) massive fluid resuscitation

Question 15

Clinical presentation of compartment syndrome

Answer 15

1) pain out of proportion 2) Pain with passive motion of muscles in compartment 3) paresis/parasthesia 4) tense compartment

Question 16

How good is clinical presentation in terms of positive predictor and negative predictor for compartment syndrome

Answer 16

Poor positive predictor 11-15% Great rule out test 97-98%

Question 17

Normal range of compartment pressures

Answer 17

< 10-12 mmHg

Question 18

When to measure compartment pressure

Answer 18

1) equivocal cases 2) unconscious patient 3) pediatric patient

Question 19

Causes of hand compartment syndrome

Answer 19

1) crush 2) fracture

Question 20

Number of compartments in the hand

Answer 20

10

Question 21

Thigh compartment syndrome cuase

Answer 21

Blunt trauma, crush, contusions

Question 22

Which thigh compartment most likely to get compartment syndrome

Answer 22

Anterior

Question 23

Gluteal compartment syndrome causes

Answer 23

1) hypogastric ligation or embolization 2) hip arthroplasty 3) prolonged compression

Question 24

Symptoms of gluteal compartment syndrome

Answer 24

1) rhabdomyolysis 2) renal failure 3) sciatic nerve palsy

Question 25

Mars protocol for first aid to hypoxic cells

Answer 25

1) maintain normal BP 2) remove constricting bandages 3) maintain limb at heart level 4) O2 supplement

Question 26

Systemic sequelae presentations - elevation in these molecules

Answer 26

1) hyper K 2) myoglobin 3) PO4 4) CPK

Question 27

Effects of myoglobinuria

Answer 27

1) nephrotoxic/ renal vasoconstriction 2) tubular casts 3) heme cytotoxic effects

Question 28

Treatment of myoglobinuria

Answer 28

1) crystalloid 2) Mannitol 3) bicarb

Question 29

Treatment goals of myoglobinuria

Answer 29

pH \> 6.5

Question 30

Role of HD in treatment myoglobinuria

Answer 30

minimal molecule too big for HD

Question 31

Contraindication to fasciotomy

Answer 31

1) non-viable tissue 2) crush injury

Question 32

Most common nerve injury in fasciotomies

Answer 32

superficial peroneal

Question 33

Course of the superficial peroneal nerve

Answer 33

Branch from common at proximal fibular head descend in lateral compartment in intermuscular septum

Question 34

Failure rate of subcutaneous fasciotomy with minimal skin incision

Answer 34

12%

Question 35

Full fasciotomy length of incision

Answer 35

12-20 cm

Question 36

Two incision technique fo LE fasciotomy

Answer 36

Ant/lat 1) between figular shaft and tibial crest 2) 4 cm lateral to crest is septum 3) raise skin flap 4) terminate fasciotomy 5cm from fibular head Post 1) skin incision 2 cm posterior to tibia 2) avoid saphenus nerve 3) cut gastroc fascia 4) cut soleus attach to tibia 5) cut fascia over flexor and posterior tibialis

Question 37

Single incision technique

Answer 37

Start with typical ant/lateral incision 2) develop posterior subcutaneous flap 3) accss fascia to superficial posterior 4) dissect flexor hallucis longus off fibula 5) mobilize peroneal neurovascular bundle posteriorly 6) incise into deep posterior compartment

Question 38

Thigh compartments

Answer 38

1) anterior 2) posterior 3) medial

Question 39

Contents of the anterior thigh compartment

Answer 39

1) sartorius 2) quadriceps 3) innervate by femoral nerve

Question 40

Contents of the posterior thigh compartment

Answer 40

1) biceps femoris 2) semimembranosis 3) semitendonosis 4) innervate by sciatic nerve

Question 41

Contents of the medial thigh compartment

Answer 41

1) Pectineus 2) obturator externus 3) Gracilis 4) adductors 5) innervate by obturator nerve

Question 42

Decompressing thigh compartments

Answer 42

1) lateral thigh intertrochanteric line down to lateral epicondyle 2) cut IT band 3) reflect vastus lateralis medially 4) enter intermuscular septum Incision on adductor muscle group to decompress medial compartment

Question 43

Gluteal compartment decompression

Answer 43

Each of the 3 muscles have own fascial compartment so incise into each

Question 44

Foot compartments

Answer 44

1) Medial 2) lateral 3) superficial 4) calcaneal 5) interosseous muscles each have one

Question 45

Foot decompression

Answer 45

1) longitudinal dorsal incision along medial part of 2nd metatarsal 2) longitudinal dorsal incision along lateral 4th metatarsal

Question 46

Upper extremity forearm compartments

Answer 46

1) Volar 2) lateral 3) extensor

Question 47

Henry's Volar fasciotomy

Answer 47

1) Single curvilineal incision proximal to ACF medial to bicep tendon 2) cross ACF crease 3) extend to radial side of forearm 4) incise each muscle of deep flexor 5) extend from lateral epicondyle to wrist between extensor carpi radialis brevis and extensor digitorium communis

Question 48

Compartments of the hand

Answer 48

total 10 1) hypothenar 2) thenar 3) adductor pollicis 4) 4 dorsal interosseous 5) 3 volar interosseous

Question 49

Releasing hand compartments

Answer 49

Longitudinal incision to release carpal tunnel +/- some interosseous

Question 50

Post-fasciotomy mortality

Answer 50

11-15%

Question 51

Post-fasciotomy major amputation

Answer 51

5-21%

Question 52

Post-fasciotomy wound complication

Answer 52

4-38%

Question 53

Post-fasciotomy neuro deficit

Answer 53

7-36% especially in forearm

Question 54

Late complications of fasciotomies

Answer 54

1) impaired sensation 77% 2) tethered tendon 7% 3) recurrent ulceration 13% 4) venous insufficiency due to lack fo calf pump 47% 5) late amputation 7.5%

Question 55

Consequence of delaying treatment in compartment syndrome \> 12 hours

Answer 55

93% neuropathy 50% amputation

Question 56

Voklmann contracture define

Answer 56

ischemic muscles fibrosis Treat with contracture and joint release

Question 57

Chronic exertional compartment syndrome (CECS) classic signs

Answer 57

1) exercise-induced 2) young 20-30's 3) athlete/runner 4) 20-30 min onset 5) 15-30 min resolve after resting

Question 58

Chances of bilateral exertional compartment syndrome

Answer 58

82%

Question 59

Differential of chronic exertional compartment syndrome

Answer 59

1) fascial hernia 2) medial tibial syndrome 3) claudication with popliteal entrapment

Question 60

Pedowitz criteria for CECS ICP

Answer 60

Pain with exercise + 1 of: 1) rest ICP \> 15 2) ICP \> 30 post exercise in first 1-2 min 3) ICP \> 20 even 5 min post exercise

Question 61

Treatment of CECS exertional compartment Different ways

Answer 61

1) Only treat anterolateral compartment 2) transverse incision 3) fasciectomy

Question 62

Outcome of CECS treatment (exertional compartment)

Answer 62

83% success at 2 years with symptom resolution

Question 63

Indications for treatment compartment syndrome with fasciotomy

Answer 63