NTCA - Rabbits Flashcards
1
Q
Upper respiratory tract obstruction
A
- Long narrow mouth, large tongue base, small diameter airway
- Use ET intubation
2
Q
Ileus (intolerance of oral intake due to inhibition of GI propulsion)
A
- Predisposed by pain, stress, starvation, change in diet
- Feed ASAP after recovery
- Admin prokinetics - metoclopramide, ranitidine
- Continue analgesia, discharge quickly
3
Q
Premed anaesthesia
A
- Opiates + midazolam combo -> sedation, muscle relaxation, dec stress
- Buprenorphine, 30 µg/kg
- Fentanyl/Fluanisone, 0.1 mg/kg
- Pethidine, 10 mg/kg
- Sedate before vascular access
- SC preferred, same dose + less painful than IM
4
Q
Pre-induction, vascular access
A
- Give EMLA cream (mix of local anaesthetics), cover w/ bandage/plastic, leave for 20 - 30 min on both ears (then sedate during this time)
- @ Marginal ear v (cephalic if large rabbit)
- 22 - 24G (blue/yellow)
5
Q
Pre-O2
A
- Face mask preferred if sedated enough
- O2 tent if stressed, aware of providing face mask quickly for induction
6
Q
Induction - inhaled
A
- Inhalent to effect = isoflurane
- Or Sevoflurane - un-licensed, but more solvent
- Face mask needed for humans, more dangerous for gas contamination
7
Q
Induction, Ketamine combos - IM
A
(Use ketamine for shorter procedures, gives 15 - 20 min procedures, be aware of cranial reflexes)
- Ketamine, 15 mg/kg
- Midazolam, 3 mg/kg
8
Q
Induction, Ketamine combo - IM/SC
A
- Ketamine, 15 mg/kg
- Medetomidine, 250 µg/kg
9
Q
Induction, Ketamine combo - SC
A
- Ketamine, 15 mg/kg
- Medetomidine, 500 µg/kg - inc dose in rabbits
10
Q
Induction, Ketamine combo - IV
A
- Ketamine, 2 mg/kg
- Medetomidine, 100 µg/kg
11
Q
Induction - ‘hyponorm’ - IV/IM
A
- Fentanyl/flaunisone, 0.1 mg/kg
- Midazolam, 0.7 mg/kg to effect
12
Q
Induction - IV to effect
A
- Propofol, 2.2 mg/kg
- Alfaxalone, 4 mg/kg
- Only use if planning to place ET tube, cause apnoea
13
Q
ET tube techniques
A
- Visual - dilate larynx w/ equipment e.g. laryngoscope + spray larynx
- Sound-guided - bung + whistle noise heard in trachea (no sound in oesophagus)
- Blind
- V-gel sits on top of larynx, prevents obstruction but not secretions/aspiration - don’t use in dentals, imaging procedures
- Laryngeal mask airway
14
Q
Anaesthesia maintenance
A
- Induction combo - ketamine may be sufficient
- Inhalant - isoflurane (sevoflurane un-licensed)
- Use non-rebreathing system, T-piece, smaller tidal vol + inc resp rate -> inc minute vol ventilation
- Reduce dead space w/ equipment, connector on ET tube, use high fresh gas flow to get rid of CO2
15
Q
Fluid therapy
A
- IV preferred (SC/IP used)
- Hartmann’s
- Higher maintenance - 10 mL/kg/hr
16
Q
Anaesthetic recovery
A
- Warm, calm environment
- Rapid return to consciousness via reversal drugs: medetomidine = atipamezole; fentanyl/fluanisone = buprenorphine (sequential analgesia, partial agonist, will displace some of fentanyl bound to receptors)
- Prevent ileus - offer food ASAP, give prokinetics, syringe feeding
- Minimise stress - rapid discharge, analgesia
17
Q
Analgesia
A
- NSAID - Meloxicam (continue via mouth), dog formulation more palatable
- Maropitant - visceral pain (not licensed)
- Opioid - Buprenorphine - long duration of action
- Local - nerve blocks (dentals - mandibular, maxillary - ensure dose below toxic); local infiltration; topical
- Adjunct - Ketamine; alpha 2-agonists
18
Q
Blood vol
A
- 55 - 65 mL/kg
- 10% loss safe
- > 15 - 20% = hypovolaemia
- Small patients, don’t want to lose much blood
19
Q
Fluid therapy
A
- Marginal ear vein IV (cephalic, saphenous)
- Intraosseous, subcut
20
Q
Surgical kit
A
- Iris scissors
- Metzenbaum scissors
- DeBakey atraumatic forceps
- Cautery - strict haemostasis
- Sterile cotton buds
- Crile + halsted forceps
- Non-powdered gloves - reduce adhesions (can form in bowels -> obstruction)
- Flush + swabs
21
Q
Suture material
A
- 4-0, 3-0 (larger rabbits)
- Absorbable synthetic = PDS, Vicryl, Monocryl
- Tissue glue - skin
22
Q
Patient prep
A
- Thin skin - easily injured + dense fur, avoid damaging during clipping + Sx (prefer intradermals)
- Gentle scrub = chlorhexidine/spirit
23
Q
Adhesion
A
- Pain and inappetance - obstruction, common after abdo Sx
- Minimise tissue handling - use appropriate instruments
- Keep tissue moist
- Meticulous haemostasis
- Minimal Sx time
- Appropriate suture material + size
- Mild cases analgesia - metacam
- Severe may require revision surgery
24
Q
Post-op complications - abscessation
A
- Thick pus - difficult to manage, redness, swelling, heat, pus
- Debride - remove all infected tissue
- Swab for C & S
- Delayed closure/2y intention healing
- Tx as abscess - leave partially open to drain + flush then remove
25
Post-op complications - wound breakdown/self-trauma
- Gentle prep of Sx site
- Meticulous Sx technique
- Appropriate suture material
- Appropriate closure - no tension, apposing wound correctly
- Analgesia following Sx - systemic + local - metacam if hydrated enough, buprenorphine
- Avoid buster collar (coprophages) - t-shirt
- Tx - revison Sx
26
Post-op complications - gut stasis
- Inappetance/gut stasis - anorexia, dec faecal output, depression
- Tempt to eat - palatable foods straight after Sx, syringe feed
- Continuous fluid therapy
- Analgesia
- Prokinetics - metoclopramide
- Anti-ulcer therapy - ranitidine
- Avoid buster collars (caecotrophy)
- Minimise stress
27
Ovariohysterectomy
- Dorsal recum -> ventral midline incision 1/2 way between umbilicus + pubic symphysis + between caudal nipples (2/3 cranial, 1/3 caudal) + remove any fat for linea alba visualisation
- Tent linea alba away from abdominal organs (no. 15 scalpel upside down) - 2 - 3 cm long, then extend w/ scissors
- Exteriorise cervix (double) -> follow to horn -> follow along cranially to exteriorise the ovary (encased in fat)
- Place 1 - 2 clamps beneath ovary pedicle + fat pad
- Make small window in mesovarium + ligate (PDS) artery (ovarian + uterine artery) in body of fat of broad ligament
- Ligate pedicle using PDS (surgeon's/modified miller's knot) + inspect for bleeding return to abdo + repeat on other side
- Incise between clamps to release ovary
- Ligate caudal to cervices (far cranial vagina) - transfixing/encircling (vicryl)
- Transect + remove uterus + ovaries
- Check stump for bleeding before release
- Routine abdo closure + avoid tension
28
Routine abdo closure
- Simple continuous - linea alba
- Simple continuous - subcut
- Intradermal if possible or skin suture = tissue glue
- 3-0/4-0 synthetic absorbable vicryl/monocryl
29
Post op care
- AB not necessary if no complications
- Analgesia (NSAIDs + opioids) - metacam, buprenorphine, maropitant (visceral pain)
- +/- Prokinetics - emeprid (metoclopromide)
- Nutritional support - syringe feeding ASAP, monitor eating + faecal output
30
Castration - modified open to closed
- Gently incise scrotal sac + vaginal tunic
- Gentle pressure to extrude testicle
- Incise tunic
- Release attachment between scrotal skin + tunica vaginalis to improve exteriorisation
- Break down ligament of head of epididymis
- Place two clamps over cord + place two encircling ligatures (within crush), cut between clamps to remove testicle
- Release cord into tunic
- Excise some proximal tunic
- Ligate tunica vaginalis = less chance of bleeding
- Repeat for other testicle
31
Castration - closed
- Incise just over scrotal sac
- Strip away vaginal tunic from scrotal sac
- Break down ligament at caudal tip of testicle
- Place two clamps on spermatic cord - one encircling + one transfixing ligature cranial to clamp -> incise between clamps
- Check stump for bleeding + release into abdo
- Repeat for other testicle
32
Castration - closure + post-op
- Skin edges opposed (simple interuprted sutures) or glued
- Separate from female for min 6 w, sperm still viable
33
Cryptorchid
- Inguinal or abdominal
- Abdo - find caudal end of tunica vaginalis in inguinal canal -> pull into inguinal region
34
Facial (subcutaneous) abscesses - remove in total
- Must radio before
- Make skin incision
- Blunt dissect skin away from abscess capsule taking care not to penetrate
- Vessels ligated/cauterised
- Skin closed
(Rarely achievable)
35
Facial (subcutaneous) abscesses - marsupialisation
- Open abscess capsule + suture to surrounding skin
- Topical antibacterial preparation applied (non-toxic if ingested) e.g. Manuka honey
- Clean w/ chlorhexidine regularly before applying preparation + flush out
- Can suture hydrocolloid dressing - draw pus away whilst protecting wound (remove in 3 - 5 d)
36
Uroliths + sludge
- Urethral obstruction - attempt to catheterise + flush into bladder + remove via cystotomy
- In bladder - remove by cystotomy
- In kidney - Sx removal not recommended
- Give fluids orally - may dilute stones
37
Cystotomy
- Dorsal recum - midline incision from umbilicus to pelvis (care not to incise bladder when cutting linea alba + avoid damage to caecum (v thin)
- Exteriorise bladder
- Moistened laparotomy swabs packed around the bladder
- Stay sutures cranial + caudal to planned incision avoiding blood vv.
- Incision in avascular area on ventral surface
- Surgical spoon used to scoop out any bladder stones (calculi)
- Catheter placed through bladder into urethra to flush further calculi out + ensure free flow of urine
- Flush bladder
- Closure - one or two layer closure, inverting suture pattern (partial thickness), leak test - inject saline
- Routine closure of laparotomy wound
