Spay/Neuter Anesthesia Monitoring in Nicaragua 2011


Quick Checklist of Responsibilities:

  • Emergency drug box
  • Patient paperwork – document everything
  • Patent catheter
  • Top-up drugs with heparin syringe
  • Monitor HR, RR and patient depth
  • Administer IV Fluids intra-operatively
  • Empty Bladder before moving to recovery
  • Pass paperwork and patient materials to recovery


Purpose/goals of monitoring during anesthesia:


  • Assess depth of anesthesia
  • Assess response to anesthetic drugs
  • Verify performance of equipment
  • Improve safety by anticipating, recognizing and correcting complications


Responsibilities Prior to surgery

  1. Assemble Emergency drug box and place in appropriate location
    1. Ensure adequate amount of drugs
    2. Calculate emergency drug doses and IV fluid bolus rate (Dogs = 90ml/kg in 15 minutes)
    3. Know location and be responsible for getting box in event of an emergency
    4. Supplies to be included:
      1. Emergency Drug Chart
      2. Epinephrine, lidocaine, atropine, dopamine (EACH LABELED)
      3. AMBU Bag, extra syringes (1cc, 3cc, 12cc at least), extra needles, extra catheters + plugs, Large tissue forceps, Heparin syringe, Calculator, Pressure infuser bag + extra bag of fluids (both crystalloid and colloid if we have it)
    5. Obtain and evaluate paperwork and patient supplies from induction team
      1. Note time of pre-meds and induction
      2. Inform surgeon of any concerns (eg Ehrlichia positive, in heat, etc. )
      3. Collect top-up drugs - there may be some variation with this as the clinic goes on
        1. Additional Ket/Val doses
        2. Additional Xylazine doses
        3. Heparin saline syringe
      4. Collect post-op drugs
        1. Rimadyl
        2. TGH meds if any
    6. Re-check
      1. ET Tube placement and cuff seal
      2. Catheter patency
      3. Patient status
    7. Administer IV Fluids to all spay patients
      1. 10 kg dog = 250 ml (subject to change)

Intra-Operative Responsibilities

  1. Begin monitoring upon transfer to surgery table – Every 5 minutes!
    1. HR, RR, oxygenation and pulse quality
      1. Stethoscope – either esophageal or regular
      2. Palpate peripheral pulse – should be synchronous with heart beat
      3. Heart Rate – may increase is depth of anesthesia is insufficient
      4. Listen to chest if possible
      5. Observe chest excursions and/or visualize/feel air via ET tube


Heart Rate (bpm)


65 - 180


100 – 220


30 – 50


60 – 100





Respiratory Rate – tends to decrease as anesthetic depth increases


Resp Rate (bpm)


8 – 15


10 – 20


6 – 8


10 – 20





    1. Oxygenation
      1. Mucus membrane color should be pink and not pale or cyanotic – cyanosis implies less than 5gm of hemoglobin = bad
      2. SpO2 > 95%
      3. Attach Pulse-Ox if available to tongue
    2. Peripheral pulse – Assess via lingual or femoral arteries
  2. Temperature measurements can be made every 30 minutes (with rectal probe only)


Rectal Temp (⁰F)


100.2 – 102.5


100.5     – 102.5

  1. Minimize heat loss during surgery if at all possible
    1. May need to “MacGyver” heating techniques – eg utilize hot water bottles from kitchen, sun-warmed towels (if not raining), additional blankets (if won’t interfere with surgery)
  2. Check for regurgitated material in the mouth – may flush with saline (or tap water) as needed but CONFIRM ET tube cuff seal is intact!
  3. Assess anesthetic depth – Evaluation of CNS 
    1. Adequate depth involves
      1. Lack of palpebral reflex – variable with ketamine
      2. Eye positioned ventro-medially
      3. Minimal (but some) jaw tone – most reliable with our drug protocols = “Mandibular relaxation”
      4. Absence of movement - Includes lack of ear flick/whisker reflex in cats
      5. Administer top-off drugs as needed – confirm with surgeon and surgeon’s assistant before administration in most cases
    2. Documentation
      1. Start time of surgery – “cutting”
      2. Additional top-up drugs administered – time and amount given
      3. Measurements of monitored variables (HR, RR, etc.) if dramatic change detected


Post surgery Responsibilities

  1. Document time at end of surgery in paperwork
  2. Disconnect IV fluid line, record amount given and heparinize catheter

10. Administer pain meds – likely injectable Rimadyl

11. Empty bladder before moving to recovery

12. Ensure all paperwork and patient materials (eg TGH drugs) follow patient to recovery


At ANY point

-       Alert surgeon and/or supervising veterinarian to concerns/questions/comments

  • Never be afraid to do this – no one will ever be mad at you for “just checking”

-       Document major concerns or observed patterns in 2010 Nicaragua Trip Log Book


Responsibilities for Recovery – 3 hours out of surgery is the critical phase

  1. Place patient on bed (likely a wooden box or suitcase) and cover with blankets and/or bear hugger if available - Minimize heat loss and keep patient as warm as possible
    1. Quiet environment 
    2. Position dog so you can visualize tongue to assess color 
    3. Assess patient status
      1. HR, RR, mucus membrane and body temperature
      2. Anesthetic depth – palpebral reflex, jaw tone, etc.
        1.                         i.     Time since anesthetic delivered – should be noted on patient chart


Approx DOA


(analgesia) 15 -  30 min

(sedation) 30 – 45 min


Up to 45 minutes**


2 – 4 hours

**Dose Dependent**

  1. Painful??? May require Xylazine or Nalbuphine administration 
  2. Document measurements on paperwork 
  3. Alert supervising veterinarians of ANY concerns and administer emergency or supportive drugs as needed/directed
  4. Extubate when dog is able to swallow twice – remember to deflate the cuff first!
  5. Complete patient chart
    1. Record temperature in 5-10 minute intervals
    2. Document time of extubation and time of departure from clinic
    3. Remove catheter only when dog is fully awake and capable of walking out the door
    4. Ensure instructions from wellness, diagnostics, and surgery are relayed to owner via translator – include TGH meds