CAL 3: Wound complications and surgical drains Flashcards Preview

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Flashcards in CAL 3: Wound complications and surgical drains Deck (53):

Would you use a surgical drain for excision of large fibroscarcoma of DSH and reconstruction with skin flaps? Why? Type?

Yes - large dead space left (ideally closed active suction drain.


Would you use a surgical drain for open traumatic wound, 8h duration, contaminated, young Dalmation Why? Type?

No - open wound drainage indicated initially. If closed subsequently, a drain may be needed.


Would you use a surgical drain for prostatic abscess in middle-aged EM lab? Why? Type?

Physiological drain (omentum) could be drained with surgical drain but less good If abscess can be resected - no drain needed but this is rarely the case


List 3 indications for use of drain

eliminate dead space remove fluid from wound (detect fluid within wound)


How should drains be chosen? 5

WOUND FACTORS - need, fluid type, location PATIENT - tolerance HOSPITAL - availability, post-op care SYSTEM - drain type and method of evacuation COST


How can dead space be eliminated generally? 3

SURGICAL - closure of tissue layers and tacking sutures PRESSURE BANDAGES - anatomy dependent SURGICAL DRAINS - if above not sufficient If in doubt, use a drain


Why might fluid removal not be possible?

access incomplete debridement too thick continued production massive contamination


How can drainage be achieved? 4

open (contaminated wound) skin fenestration (grafts) physiological implant (omentum) surgical implant (drain)


How can drains be classified? 6

MECHANISM OF ACTION - active/passive TYPE OF IMPLANT - surface acting/ tube drain NUMBER OF LUMENS - single/double/triple SUCTION SYSTEM - commercial/home-made SUCTION PRESSURE - gravity/low/high SUCTION TYPE - closed/vented


What are the properties of an ideal drain? 5

inert soft radioopaque easy to handle cheap


What is the benefit of a closed system for an active drain?

reduces risk of ascending infection


What is this? Advantages Disadvantages? Uses?

WHAT: Penrose drain, flat cylinder, latex/silicone ADVANTAGES: soft, malleable, easily sterilised, doesn't exert pressure DISADVANTAGES: can't apply suction, limited efficiency, ascending infection more likely, inflammatory action great with latex USES: salivary mucocoele, abscesses


What is this? Advantages Disadvantages?

WHAT: strip drain, (penrose drain with a cut in it) ADVANTAGES: smaller, high surface area DISADVANTAGES: tricky to make, harder to hanle, structurally weaker


What is this? Advantages Disadvantages?

WHAT: cigarette drain (gauze tape in a penrose drain) ADVANTAGES: capillarity, inside/outside drain DISADVANTAGES: inflammation, increases wicking


What is this? Advantages Disadvantages?

WHAT: dental dam, latex rubber sheet rolled into tubes ADVANTAGES: as penrose (soft, malleable, easily sterilised, doesn't exert pressure) and high surface area DISADVANTAGES: cut to size and roll, difficult handling


What is this? Advantages Disadvantages?

WHAT: corrugated drain, flat and ribbed, rubber/PVC ADVANTAGES: large diameter/variable size DISADVANTAGES: bulky, more rigid (tissue trauma)


What is this? Advantages Disadvantages?

WHAT: Yeates drain, series of tubes

ADVANTAGES: large diameter, variable size, lumina DISADVANTAGES: bulky, rigid


What is this? Advantages Disadvantages?

WHAT: tube drain - cylindrical, rubber/PVC, fenestrations ADVANTAGES: can apply suction DISADVANTAGES: rigid, lumen occlusion, collapse if excessive suction


What is this? Advantages Disadvantages?

WHAT: tube drain - FLAT, flattened cylinder, silicone rubber, fenestrations ADVANTAGES: can apply suction DISADVANTAGES: rigid, lumen occlusion, collapse with excessive suction, expensive


What is this? Advantages Disadvantages?

WHAT: sump drain, (tube drain with 2 lumina) ADVANTAGES: vented suction, for body cavities ? DISADVANTAGES: contamination (bacterial filter needed), omentalisation (blocked)


What is this? Advantages Disadvantages?

WHAT: sump-penrose (+/- fenestrations, +/-gauze) ADVANTAGES: reduced blocking DISADVANTAGES: contamination, inflammation (gauze), inefficient for intended use


What is this? Advantages Disadvantages?

WHAT: modified sump-penrose ADVANTAGES: wound irrigation DISADVANTAGES: don't need irrigation


How can you drain the abdomen? 2

abdominal drain OR open peritoneal drainage


Aims of suction - 6

obliterate dead space no tissue damage no air ingress no fluid reflux into wound (1 way valve) air-tight closure of wound or vacuum lost


List 3 suction generators

syringe portable container vacuum container


How can closed suction be achieved?

IMPLANTS: negative pressure applied single lumen drain


What are the advantages of closed suction? 4

wound and dressing kept dry reduces incidence of seroma/haematoma reduces bacterial ascension reduces infection rate


How can vented suction be achieved?

Negative pressure (continuous generator) Double/multi-lumen drain (sump drain) Egress - wound fluid Ingress - air


+/ - of vented suction

ADVANTAGES: efficient for removing large volumes, reduces likelihood of drain collapse DISADVANTAGES: air passage may be traumatic, increased risk of ascending infection (filter air)


What are the general rules of drain placement?

avoid nn and BVs avoid anastomotic sites avoid contact with suture line avoid drain when closing wound anchor drain (within wound, at exit site)


What are the general rules for the drain exit hole?

Minimum umber of exit holes clip hair around hole (pre-op) not through primary wound not through flap base exit dependently exit hole of sufficient size


How do you place an active and passive drain in surgery?

Passive - forceps and sclapel Active - trochar


Indications - blind drain placement - 3

if wound not explored if large cavity unexplored if wound already closed


How do you blindly place a drain?

stab incision forceps into wound cavity pass suture blindly close to forceps traction on drain confirms engagement


How can you anchor a Penrose drain?

in wound - within wound (tears out at removal) or non-absorbable suture outside wound (cut out at removal) OR at wound surface - non-absorbable suture


How do you anchor a tube drain? 3

***N.b. all tube drains must be anchored*** Chinese finger-trap (lumen occlusion, drain too soft, if small diameter) Tape butterfly (for small tubes, loosens if wet) Both!


When do you remove a drain?

When it has done its job (!) Monitor fluid production Approximate times: 24h - capillary bleeding 2-3d - traumatic wound 2-5 d - large dead space


List some examples of drain complications

wound infection wound dehiscence premature loss retention of drain failure of drainage loss of suction blocked drain pain and irritation drain tract cellulities misuse and over-reliance


How may a seroma be managed?

conservatively or by aspiration is this fails to resolve the seroma, or if the seroma is large and potentially affecting wound healing, a surgical drain may be indicated


What might happen after a thoracotomy for removal of a lung tumour?

No wound drain - no fluid or dead space


A chest drain (thoracostomy tube) will be placed to drain air from the pleural space after surgery to ensure that the normal mildly sub-atmospheric pressure of the pleural space is re-established.


What is a seroma?

a pocket of clear serous fluid, may develop post-surgery


What proportion of the circumference of a limb that is degloved impairs venous and lymphatic drainage?

Large wounds that involve more than 180 degrees of the circumference of the limb may impair venous and lymphatic drainage (= ' a physiological tourniquet') and result in swelling of the distal limb


What healing complications are wounds over the flexor and extensor aspects of a carpus prone to?

contracture deformity (if they heal) or a non-healing wound (if they don't heal)


Why is it oten difficult to re-attach the skin to the gingiva?

sinc ethe gingiva has a low collagen content and hold sutures poorly. 


What are predisposing factors for a seroma to develop in intercostal tissue?

incision of well vascularised tissue (i.e. muscle)
continuous movement (thoracic limb)

loose skin


To avoid, ensure: atraumatic technqiue, accurate apposition of layers, oblieration of dead space.


What is necrotising fasciitis (NF)?

= flesh eating bacteria syndrome


rare infection of deeper skin and SC layers

esilt spreads across fascial plane within SC tissue

caused by various different bacteria


large wounds developing due to vascular injury are a form of 'physiological' degloving and tissue loss may be extensive, resulting in exposure of the underlying bone.


What is von Willebrand's disease?

disorder or primary haemostasis and platelet-type bleeding, may be serious in affected individuals, Doberman's are prone. 


TESTING: Ag testing and/or a buccal mucosal bleeding time


Why is bandaging of the head and neck difficult?

risk of occlusion of the veins and lymphatics an dpotentially the oesophagus and trachea


What might leaving a sequestrum that formed due to osteomyelitis cause?

remember the sequestrum is devoid of blood supply. It may result in a chronic draining tract which will not resolve until the sequestrum is removed. 


What might a LN excision lead to?

oedema of the body part distal to the LN until the afferent and efferent lymphatics anastomose. Excision of some LNs (e.g. popliteal) are ore commonly associated with this than others (e.g. prescapular).


Why might previously irradated areas be a problem during wound healing?

they have a poor blood supply and healing may progress more slowly than normal or may stop. In the latter, provision of tissue with a good blood supply e.g. omentum or a muscle flap may be needed.


What are risks associated with managing an open wound immediately ventral to the eyelid by second intention healing?

contracture deformity resulting in acquired:



stenosis of the palpebral orifice


What is a grass awn?

grass seeds which are sharp and have the ability to burrow into the skin of dogs (e.g. interdigital region)

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