Case Study Fluid Management for Craniofacial Resection with Rectus Free-Flap

1
Case StudyFluid Management for Craniofacial
Resection with Rectus Free-Flap

• D. John Doyle MD PhD FRCPC
• Cleveland Clinic Foundation
• doylej_at_ccf.org March 2003

2
Case Craniofacial Resection with Rectus Free-Flap

• A 76 year-old male, weighing 81 kg who was 185
  cm tall, presented with complaints of facial pain
  and swelling. The patient had smoked a pack of
  cigarettes a day for almost 50 years. About 10
  years ago, he developed angina while playing
  tennis. The angina was treated with the
  beta-blocker atenolol and the patient quit his
  smoking habit. At the time of diagnosis, the
  patient reported that his infrequent
  anginaattacks responded quickly to sublingual
  nitroglycerine tablets. Hedescribed his exercise
  tolerance as good, being able to climb three
  flights of stairs before "getting pooped". The
  patient took no other medications and had no
  allergies.

3
Remember

• 76 year-old male
• Former smoker
• CHD
• Complaints of facial pain and swelling

4
Diagnosis

• A diagnosis of squamous cell carcinoma of the
  maxillary sinus was made bymagnetic resonance
  imaging and confirmed by biopsy following a
  workup.

5
Surgical Plan

• SURGERY
• The surgical plan was to undertake a 10-hour
  craniofacial resection of the right maxilla and
  orbit and to replace the defect with a rectus
  muscle free-flap using microvascular techniques.
  A three litre blood loss is expected.
• 10-hour craniofacial resection
• 3 L expected blood loss

6
Preoperative Tests

• Laboratory results included a hemoglobin
  concentration of 13 g/dL, a creatinine of 1.1
  mg/dL. Vital signs, serum electrolytes,
  electrocardiogram and chest X-ray were all
  unremarkable. Hb 13 g/dL Creatinine 1.1
  mg/dL

7
Coronary Artery Disease

• Although this patient appeared to be in fairly
  good shape, with good exercise tolerance, he had
  known coronary artery disease.
• Because of his coronary artery disease, most
  anesthesiologists would not allow his hemoglobin
  to drop significantly below 10 g/L.

8
Blood Volume Estimate

• Using 65 mL/kg as a blood volume estimate, his
  blood volume (BV) was calculated to be about 5300
  mL.

9
ABL2(5300) x (130-100)/(130100)1400 mL
(approx.)

• This suggests that with appropriate fluid
  replacement using crystalloid or colloid, the
  patient could lose up to about 1400 mL of blood,
  before a transfusion of packed red blood cells
  would likely become necessary. If serial blood
  samples were taken from an arterial line, it
  would be possible to know exactly when a minimum
  acceptable hemoglobin or hematocrit had been
  reached.

10
ABL Formula

• The allowable blood loss (ABL) was estimated
  using the following formulaABL2BV x (Starting
  Hb-Allowable Hb)/(Starting HbAllowable
  Hb)ABL2(5300) x (130-100)/(130100)1400 mL
  (approx.)

11
Two options to replace ongoing blood losses

• 41 with a crystalloid such assaline or Ringers
  lactate solutionor
• 11 with a colloid such as PENTASPAN (10
  pentastarch in 0.9 sodium chloride injection)
  This is given in order to keep the patient
  isovolemic.

12
Rule of Thumb

• One often used "rule of thumb" is to replace
  initial blood losses with crystalloid such as
  saline on a 41 basis until blood losses reach
  15-20 of blood volume. Replace subsequent losses
  11 with a colloid such asPENTASPAN (to keep
  patient isovolemic) until the hemoglobin or
  hematocrit falls below the "transfusion trigger".

13
Rule of thumb Start Colloids at 15 - 20 Blood
Volume Loss

• Example (20 blood loss rule of thumb)
• 77 kg man
• Blood volume estimated at 65 ml/kg x 77 kg 5
  liters
• 20 blood volume 1 liter of blood
• Crystalloid replacement for 1 liter blood is 3-4
  liters
• Thus, consider starting a colloid after 3-4
  liters of crystalloid given to replace lost blood

14
Transfusion Trigger

• In this case, a transfusion trigger of 10 g/dL
  would be used because of thepatient's
  cardiopulmonary disease. In a much younger
  patient without anyknown cardiopulmonary
  disease, the trigger level might be set at 8 or
  even 7 g/L, depending on clinical judgement.

15
Remember

• ABL 1400 mL
• 4 L of crystalloid replaces 1 L of blood loss
• Further blood loss replaced with PENTASPAN
• Transfusion trigger 10 g/L

16
Preoperative Fluid Deficits

• Preoperative fluid deficits are often
  estimated using the 4-2-1 rule. For an 81 kg
  patient this amounts to about 130 mL/hr. Assuming
  that the patient has been NPO for about 10 hours
  preoperatively and has had no IV prior togoing
  to the OR, the preoperative fluid deficit would
  be about 130 mL/hr x 10 hrs 1300 mL. Many
  anesthesiologists attempt to replace this deficit
  over about a two hour span at the beginning of
  the case.

17
4-2-1 Rule

• 4 ml/kg/hr for first 10 kg
• 2 ml/kg/hr for next 10 kg
• 1 ml/kg/hr thereafter
• EXAMPLES
• 10 kg 40 ml/hr
• 20 kg 60 ml/hr
• 30 kg 70 ml/hr
• 40 kg 80 ml/hr
• 70 kg 120 ml/hr

18
Maintenance Fluid Requirements

• Maintenance fluid requirements would amount to
  about 130 mL/hr

19
Third Space Losses

• Third space losses include both evaporative
  losses from surgical area and fluid that enters
  the interstitium as a result of tissue trauma.
  For a case such as this one, a reasonable
  estimate of the third space losses would be about
  4 mL/kg/hr or about 320 mL/hr.

20
Remember

• Preoperative fluid deficit anticipated at 1300 mL
• Third space losses of 320 mL/hr expected
• Maintenance fluid requirements of 130mL/hr
  expected

21
Desired Fluid Therapy 1

• Run the IV at 450 mL/hour (130 mL/hr
  maintenance 320 mL/hr third space loss
  replacement) throughout course of treatment.In
  addition, for the first two hours add 650 mL/hr
  to the above amount to replace the 1300 mL
  deficit over 2 hours. The infusion rate will then
  be 1100 mL/hr (450 mL/hr 650 mL/hr) for the
  first two hours.

22
Desired Fluid Therapy 2

• Switch predominately to PENTASPAN 11 to
  replace the ABL of 1400 mL, with use of
  crystalloids as judged clinically appropriate by
  anesthesiologist.Transfuse packed cells when
  hemoglobin falls below the "transfusion trigger"
  of 10 g/dL.

23
Remember

• Run IV at 450 mL/hr. throughout treatment course
  to replace intra-op fluid losses
• Add 650 mL/hr over first two hours to replace
  pre-op deficit
• Add PENTASPAN to replace ABL of 1400 mL
• Transfuse with packed cells when transfusion
  trigger of 10 g/dL of hemoglobin is reached

24
Final Note

• Note These are starting points only. Most
  anesthesiologists would insert a CVP line, an
  arterial line and a Foley catheter in this
  patient to further guide fluid therapy. Fluid
  delivery may have to be increased should oliguria
  or hypotension occur.

25
The End