Tubes and drains

Question 1

Why would feeding tubes be needed?

Answer 1

Inappetant/anorexic patient

Avoid oral contamination of wounds

Bypass obstruction

Potential anorexia postoperatively

Administer medication

Avoid parenteral nutrition

Question 2

How are animals tube fed?

Answer 2

Use as much of the GI tract as possible

Consider
○ Location of disease
○ Length of time support likely to be needed
○ GA risk
○ Patient and owner compliance

Question 3

Liquid or blended food diet calculation

Answer 3

RER (kcal/day) = 30 x (current body weight in kg) + 70

Likely to need more than the resting value so add e.g. 10% depending on needs

Question 4

Types of feeding tube

Answer 4

Naso-oesophageal tube

Oesophagostomy tube

PEG tube

Surgical gastrostomy tube

[Jejunostomy tube]

[Gastrojejunostomy tube]

Question 5

Drugs that can be used to stimulate an animal to eat on their own

Answer 5

Maropitant [CereniaTM]
- anti-emetic.
- Very expensive so care for larger patients.

Capromorelin [EntyceTM – dogs, EluraTM – cats]
– appetite stimulant

Mirtazapine
– appetite stimulant, but also has anti-nausea properties.
- More effective in cats than dogs (and only licenced in cats).

Cyproheptadine [PeriactinTM]
– appetite stimulant.

(diazepam)
- not meant to be used as an appetite stimulant.
- In cats can cause an idiosyncratic necrosis of the liver(?)

Question 6

Advantages of naso-oesophageal tubes

Answer 6

No GA required

Quick and simple to place

No complex equipment required

Generally well tolerated

Question 7

Disadvantages of naso-oesophageal tubes

Answer 7

Small diameter tube - can only use liquid food and medication, crushed tablets will likely cause an obstruction.

Easily displaced by patient

Usually requires Buster collar

Cannot be used to give most medications

Feeding <1 week duration

May be unsuitable if vomiting

Question 8

NO tube placement

Answer 8

Calm environment

Much easier to place in cats than dogs, dogs will sneeze and go a bit crazy

Instil local anaesthetic into both nostrils - wait 5 mins for maximal effect

Pre-measure tube to 8th-9th rib and place marker

Lube

Push external nares dorsally and push tube into ventromedial meatus

Observe for swallowing once tube reaches pharynx

Check placement

Secure as close to nostril as possible

Question 9

How do verify NO tube placement?

Answer 9

Vacuum on aspiration

Injection of water well tolerated

Radiography?

Recheck before each feed

Question 10

Advantages of oesopagostomy tubes

Answer 10

Long-term feeding possible - can stay in for weeks

Home care possible

Early removal ok - can remove whenever the animal starts to eat

No concern for peritonitis

Simple to place

Well tolerated

Larger tubes – blended food + medication

Feeding can be initiated immediately

Patients usually happy with oral feeding around the tube

Question 11

Disadvantages of oesophagostomy tube placement

Answer 11

Can be difficult to place in larger/obese patients

Not suitable if oesophageal dz

May be unsuitable if vomiting

Stomal infection may occur

Leakage of food into peri-oesophageal tissues possible

Require GA for placement

Question 12

O tube placement

Answer 12

GA

Left (or right) side of neck – lateral recumbency

Mostly need the long haemostat- the bigger the patient, the bigger the haemostat needed

Check position of jugular vein

Pre-measure tube to 7th/8th rib

A non-sterile assistant places large, curved forceps into the oesophagus from the oral cavity and uses them to tent the skin of the mid-cervical region

Vet wearing sterile gloves makes a stab incision onto the forceps and forceps pushed through the skin.

Oesophagostomy tube grasped with the forceps and pulled through into the oral cavity.
The tube is then turned and the distal end pushed down the oesophagus

The proximal end of the tube is pulled gently until the tube comes to lie flat against the neck.

Radiograph before securing to ensure the distal tip is not too cranial or caudal (ideally 7th/8th rib)

Two finger trap sutures to secure

Shorten tube if possible

Bandage in loosely

Question 13

Advantages of gastrostomy tubes

Answer 13

Suitable for long term feeding

Well tolerated

Do not interfere with voluntary intake

Low profile tube possible

Home care possible

Can be placed during abdo sx, as PEG tube or via minimal flank approach

Question 14

Disadvantages of gastrostomy tubes

Answer 14

More accessible to patient interference

May not be suitable in vomiting patients

Require GA for placement

Risk of peritonitis

Should not be removed before 7-10d

PEG tube requires expensive equipment and some operator expertise

Question 15

Indications for gastrostomy tube

Answer 15

When abdominal surgery already being performed

If oesophageal/cervical disease

If vomiting patient

Question 16

Surgical G-tube placement

Answer 16

Mushroom tipped tube if possible, otherwise Foley catheter

GA

Ventral midline coeliotomy

Forceps pushed through abdominal wall muscle just caudal to last rib in the ventral 1/3 abdomen – stab incision made in skin and forceps pushed through. Distal tip of tube grasped and pulled through the body wall.

2 x stay sutures placed in stomach

Purse string suture placed in body of stomach on left side

4 x pexy sutures placed around the tube site between the stomach and abdominal wall to secure.

Double finger trap suture to secure

Question 17

Feeding tube removal

Answer 17

Can be done in the conscious patient
○ Potential exception of G-tube in cats

Remove any dressing to expose stoma.

Cut finger trap/butterfly connector suture(s).

Gently pull the tube out.

Clean (dilute chlorhexidine) and dry the stoma.

Apply a Primapore dressing.

The stoma will close by second intention healing over a few days.

Question 18

Indications for wound drain use

Answer 18

Obliteration of dead space

Removal of pre-existing fluid and air from a wound/body cavity

To prevent anticipated fluid or air accumulation within a wound/body cavity

Question 19

Potential risks of wound drains

Answer 19

Ascending infection (hospital acquired)

Wound dehiscence
○ Drains should ALWAYS exit separately from the sutured wound site.

Occlusion

Premature drain removal

Drain breakage/retention

Question 20

Types of wound drains

Answer 20

Passive drain

Active suction drain

Physiological drain (omentum)

Tube drain

(leave distal wound open)

Question 21

Penrose drains

Answer 21

Passive drain type

Made of soft latex

Flattened tube

Easy and cheap

Relies on gravity, capillary action and overflow so limited locations

Should have a single ventral exit point

Cover with sterile absorbent contact layer and bandage or if not possible, use petroleum jelly ventral to drain

Question 22

Indications for active suction drains

Answer 22

Oncological defects

Infected/contaminated wounds

To manage seromas

Question 23

Active suction drains

Answer 23

E.g. Mini Red-o-Pack Suction Drains or Mila spiral drains

Can place open or closed

All fenestrations must lie within the surgical wound

Exit site is not important as these drains do not rely on gravity

Secured using a fingertrap suture

Activated 6-8 hours after placement once a fibrin seal has formed at the wound site allowing negative pressure to be maintained.

Secured to the patient using a stockinette bandage or harness

Removal of the drain is performed when fluid production has reduced to <2-4mls/kg/day

Question 24

Advantages of active drains over passive drains

Answer 24

Closed system

Work independent of gravity

Volume of fluid can be recorded

Reduced risk of ascending infection

No skin scald

Repeat cytology possible

Question 25

Omentum as a wound drain

Answer 25

Physiological drain

Promotes angiogenesis, improves immune function, provides lymphatic drainage

Can be tunnelled to distant site

May not be possible in neutered female or following previous abdominal surgery

Herniation/strangulation of the omental pedicle possible at abdominal exit site