OPTIMIZED CARDIOPULMONARY BYPASS PRIME & TECHNIQUE IN THE NEONATE: A journey from Snow to Sunshine

Bharat Datt,Msc,CCP,CPC,FPPChief pediatric perfusionistThe Heart center atThe Arnold Palmer Hospital for Children

WHAT PERFUSIONISTS DO

DISCLOSURES

• I have no disclosures or conflict of interest’s regarding this presentation.

• The IRB at Arnold Palmer has classified the data I’m presenting as QI and given me the requisite permission.

BP-50 circuit with KAVD

GOALS/OVERVIEW

• Reduce Static priming volume• Reduce Dynamic priming volume or dead space• Reduce transfusion• Increase M.U.F efficacy• Increase EFFICIENCY-Faster set-up time• Increase SAFETY• Impact outcomes & Reduce mortality/morbidity• Ability to operate on smaller kids & previously

inaccessible populations eg: Jehovah’s witness

How do we do this…….

• GO SMALL• TREAT EVERY PATIENT AS A 2 KG NEONATE FROM

THE PERFUSION PERSPECTIVE• Treat every patients as a Jehovah’s witness • At the least be aggressive in fluid management from

the perfusion perspective• Incorporate 3/16 inch arterial line in circuit• Incorporate smaller static prime volume CPB

components• Reduce dead space thereby reducing dynamic prime.• ↑ M.U.F EFFICACY

Every little drop counts

HMS Hemochron

3/16th Arterial line

• ¼ inch arterial line occupies 9.65 ml/ft• 3/16 inch arterial line occupies 5 ml/ft

• So hypothetically a 5 foot ¼ inch line would occupy 9.65 x 5 =48.25 ml

• A 3/16 inch arterial line would occupy 25 ml of volume

• In a 2.5 or 1.8 kg kid-huge difference.

ON CPB with a partial unit

Should we use Venous assist ?

• JECT:2013;45:128-132• Timothy.W.Willcox-Greenlane hospital-

Auckland• Application of VAVD is not without

consequence• Initially used to facilitate smaller cannulae• Increasingly used to miniaturize circuit

Class II recommendations for VAVD by AHA

• IIa-weight of evidence in favor of the usefulness/efficacy of clinical practice

• IIb- usefulness/efficacy less well established• IIC-lowest rank of evidence where expert

consensus is the primary basis for recommendation

• VAVD assigned class IIc• VAVD maybe of benefit on the basis of expert

opinion but no hard evidence

Increase in emboli transmission .

• Thiara AS,Eggereide S,Pedersen T,Lindberg H,Fiane AE.In vitrio & in vivo evaluation of Dideco’s pediatric cardiopulmonary bypass circuit for neonates weighing less than five kilograms.Perfusion.2010;25:229-35

• Hudacko A,Sievert A,Sistino J.Gaseous microemboli in a pediatric bypass circuit with an unprimed venous line:An in vitro study.JECT.2009;41:166-71

STS-blood conservation guidelines in respect to VAVD with the society of cardiovascular anesthesiologists special task force on blood transfusion & the international consortium for evidences based perfusion

• VAVD in conjunction with mini-circuits may prove useful in bleeding & blood transfusion as part of a multi-modality program

• Given the potential limitations of VAVD, use of this technology necessitates caution & adjustment of perfusion technique

• May provide benefit, especially in pediatric patient

• VAVD may or may not cause hemolysis within CPB circuit

Negative impact of venous assist2000 Key West outcomes meet

• Cerebral emboli during CPB have been positively co-related with ↑ neurocognitive dysfunction

• VAVD employed clinically without CPB component redesign

• Advantages must be balanced against potential hazards

SAFETY WITH SORIN ROLLER HEAD

• Separation of venous assist from the arterial tree (VAVD) by occlusive roller head thereby preventing cerebral/other steal

• Hypothetically increase ability for de-bubbling of venous blood through venous reservoir de-foamer

• Faster set up/prime time . Increased efficiency in emergent situations

• Higher peak tissue perfusion pressure by a positive displacement (roller) pump

SAFE USE OF VAVD

•Necessitates refinement of perfusion technique• Judicious choice of application•Further development of the components of CPB circuit

Jorge Ojito’s paper

WHY LEAVE TRANSFUSION FOR LAST?

• Transfusion in CABG is associated with reduced long term survival Colleen Gorman Koch et al Cleveland Clinic

• Annals of thoracic surgery,vol 81,may 2006;81:1650-7

• Risk of death bi-phasic• Early risk up to 6 months• Late risk upto 10 years

Lowest hematocrit on CPB and in-hospital outcomes

Lowest Hct on CPB (%)Outcome <19 19-20 21-22 23-24 ≥25 p value**

N (Total = 6,980) 994 1,507 1,426 1,357 1,696

In-hospital mortality (%) 3.9 3.3 2.8 1.5 1.6 <0.001

Intra- or post-op IABP (%) 6.1 5.8 5.1 5.2 3.6 <0.001

Return to bypass pump (%) 7.5 5.4 4.9 4.1 3.8 <0.001

Intra- or post-op stroke (%) 2.2 0.9 1.7 1.7 1.8 0.736

Return to O.R. for 3.4 2.5 2.4 2.6 2.5 0.310post-op bleeding (%)

* adjusted for: age, sex, BSA, comorbidity, prior CABG surgery, pre-op LVEDP, pre-op EF, left main stenosis and priority at surgery** p of trend

Northern New England Cardiovascular Disease Study Group 2/02

Transfusion Strategies for Patients in Pediatric Intensive Care Units. Jacques Lacroix, Paul C. Hébert,James S. Hutchison et al. for the TRIPICU Investigators, the Canadian Critical Care Trials Group, and the Pediatric Acute Lung Injury and Sepsis Investigators NetworkN Engl J Med 2007; 356:1609-1619April 19, 2007DOI: 10.1056/NEJMoa066240

• Optimal Hb threshold for kids• N=637.All kids with Hb< 9.5 7 days into admission• 2 groups. 320 patients to transfusion threshold of 7• 317 patients to a transfusion threshold of 9.5 g/Dl• 14 deaths in each group• No difference in adverse outcomes• In stable, critically ill children a hemoglobin

threshold of 7 g per deciliter for red-cell transfusion can decrease transfusion requirements without increasing adverse outcomes.

Blood transfusion determines postoperative morbidity in pediatric cardiac surgery applying a comprehensive blood-sparing approach.Redlin M1, kukucka M, Boettcher W et alJ of Thorac cardiovasc surg. 2013 Sep;146(3):537-42

• OBJECTIVE: • Recently we suggested a comprehensive blood-sparing approach in pediatric cardiac surgery that resulted in no

transfusion in 71 infants (25%), postoperative transfusion only in 68 (24%), and intraoperative transfusion in 149 (52%). We analyzed the effects of transfusion on postoperative morbidity and mortality in the same cohort of patients.

• METHODS: • The effect of transfusion on the length of mechanical ventilation and intensive care unit stay was assessed using

Kaplan-Meier curves. To assess whether transfusion independently determined the length of mechanical ventilation and length of intensive care unit stay, a multivariate model was applied. Additionally, in the subgroup of transfused infants, the effect of the applied volume of packed red blood cells was assessed.

• RESULTS: • The median length of mechanical ventilation was 11 hours (interquartile range, 9-18 hours), 33 hours (interquartile

range, 18-80 hours), and 93 hours (interquartile range, 34-161 hours) in the no transfusion, postoperative transfusion only, and intraoperative transfusion groups, respectively (P < .00001). The corresponding median lengths of intensive care unit stay were 1 day (interquartile range, 1-2 days), 3.5 days (interquartile range, 2-5 days), and 8 days (interquartile range, 3-9 days; P < .00001). The multivariate hazard ratio for early extubation was 0.24 (95% confidence interval, 0.16-0.35) and 0.37 (95% confidence interval, 0.25-0.55) for the intraoperative transfusion and postoperative transfusion only groups, respectively (P < .00001). In addition, the cardiopulmonary time, body weight, need for reoperation, and hemoglobin during cardiopulmonary bypass affected the length of mechanical ventilation. Similar results were obtained for the length of intensive care unit stay. In the subgroup of transfused infants, the volume of packed red blood cells also independently affected both the length of mechanical ventilation and the length of intensive care unit stay.

• CONCLUSIONS: • The incidence and volume of blood transfusion markedly affects postoperative morbidity in pediatric cardiac surgery.

These results, although obtained by retrospective analysis, might stimulate attending physicians to establish stringent blood-sparing approaches in their institutions

Effects of a comprehensive blood-sparing approach using body weight-adjusted miniaturized cardiopulmonary bypass circuits on transfusion requirements in pediatric cardiac surgery.Redlin M1, Habasettl L, Boettcher W et al.J Thorac cardiovasc surg 2012 Aug;144(2):493-9.

• OBJECTIVES: • Transfusion-free pediatric cardiac surgery remains a challenge, mainly owing to the mismatch between the

cardiopulmonary bypass (CPB) priming volume and the infants' blood volume. Within a comprehensive blood-sparing approach, we developed body weight-adjusted miniaturized CPB circuits with priming volumes of 95, 110, and 200 mL for, respectively, infants weighing less than 3 kg, 3 to 5 kg and 5 to 16 kg. We analyzed the effects of this approach on transfusion requirements and risk factors predisposing for blood transfusion.

• METHODS: • A total of 288 children with body weights between 1.7 and 15.9 kg were included and divided into 3 groups:

No transfusion, postoperative transfusion only, and intraoperative and postoperative transfusion. Groups were compared by analysis of variance or analysis of variance on ranks. Risk factors predisposing for transfusion were identified by multivariate logistic regression.

• RESULTS: • Of the infants, 24.7% required no transfusion, 23.6% received postoperative transfusion only and 51.7%

received intraoperative and postoperative transfusion. Groups differed by age, body weight, and size and by duration of surgery, CPB, and aortic crossclamp (P<.00001). Body weight (P<.00001), CPB duration (P<.00001), and persisting cyanosis (P=.03) were predictors of intraoperative and postoperative transfusion, whereas body weight (P=.00095), reoperations (P=.0051), and cyanotic heart defects (P=.035) were associated with postoperative transfusion only.

• CONCLUSIONS: • Our blood-sparing approach allows for transfusion-free surgery in a substantial number of infants. The

strongest predictors of transfusion requirement, body weight and complexity of surgery as reflected by CPB duration, are not amenable to further improvements. Better preservation of the coagulatory system might allow for reduction of postoperative transfusion requirements.

Blood Transfusion in Pediatric Cardiac SurgeryYves DurandyArticle first published online: 24 NOV 2010DOI: 10.1111/j.1525-1594.2010.01158.x

• CPB-VAVD,microplegia,miniaturized bypass circuit• 46 patients weighing 5.1 ± 1.5 kg • CPB prime was 100 mL for patients up to 3.5 kg, 120 mL

for patients between 3.6 and 7.5 kg, and 160 mL for patients between 7.6 and 8.6 kg.

• The volume of blood transfusion was 271 ± 112 mL• hemoglobin level before surgery was 10.3 ± 1.7 g/dL,

hemoglobin level during surgery was 11.0 ± 1.5 g/dL, and hemoglobin level after the last transfusion was 12.3 ± 2.4 g/dL.

• The mean blood transfusion volume was equivalent to 60% of the patient's total blood volume (estimated to be 80 mL/kg).

Blood Transfusion After Pediatric Cardiac Surgery Is Associated With Prolonged Hospital Stay. JW Salwin,MA Scheurer.PC Laussen et alThe Annals of Thoracic Surgery, Volume 91, Issue 1, January 2011, Pages 210-211

• Patients discharged after cardiac surgery in 2003 were retrospectively reviewed. The red blood cell volume administered during the first 48 postoperative hours was used to classify patients into nonexposure, low exposure (≤15 mL/kg), or high exposure (>15 mL/kg) groups. Cox proportional hazards modeling was used to evaluate the association of red blood cell exposure to length of hospital stay (LOS).

• Blood transfusion is associated with prolonged hospitalization of children after cardiac surgery, with biventricular patients at highest risk for increased LOS. Future studies are necessary to explore this association and refine transfusion practices.

RETROSPECTIVE DATA

• Compared 2 sets of patients• Control group- patients with Biomedicus &

KAVD• Study group- roller with gravity drainage• Inclusion criteria- use of Baby FX-05• Exclusion criteria- CPS or ECMO• N=30 in study group-roller arterial pump• N=35 in control group-biomedicus arterial

pump

Comparison

• Inclusion criteria-Baby FX-05 with ¼ inch or 3/16 inch arterial line

• Biomedicus pump time 164 61, AOXCL 80 63• Roller pump time 186 101,AOXCL 92 65• Biomedicus- 2 pts circ arrest with ante cerebral

perf• Roller-3 pts circ arrest with ant cerebral perf• EXCLUSION CRITERIA-CPS or ECMO• Biomedicus wt 5.632.9,BSA 0.35 m2• Roller wt 6.262.3,BSA 0.37 m2

PRIME VOLUME-Neonate

PRIME VOL450

Biomedicus Roller0

50

100

150

200

250

300

350

400

450

PRIME VOLM

l

450 P<0.001

230

PRIME HCT-Neonate

Biomedicus Roller0

5

10

15

20

25

30

PRIME HCT

HC

T P<0.000128.4

19.7

CPB HCT-first ABGBiomedicus Roller

0

5

10

15

20

25

30

Initial HCT on CPB

HC

T 26.7 30.2

Circuit residual vol/cell saver vol processed

197.83711021926 pts 0 vol to process

BiomedicusCUF

BiomedicusMUF

RollerCUF

RollerMUF

0 50 100 150 200 250 300 350 400 450 500

CUF/MUF Volume

Mls

460

427

187

227

27 pts cell saver vol processed 0 ml

Post MUF HCT-Neonate

BweanHCT

BMUFHCT

RweanHCT

RMUFHCT

0 5 10 15 20 25 30 35 40 45

AVG=37.5

AVG=32

AVG=39

AVG 34

INTRA-OP BLOOD PRODUCT USE

BmedicusRBCprim

BmedicusRBCCPB

RollerRBCprim

RollerRBCCPB

0 50 100 150 200 250

221+62

131+44

154+98

190+138

P>0.00001

CPB prime-ped & above

BMprime Rollerprime0

100

200

300

400

500

600

700

800

900

822

426 Series1

n=8

n=6

Transfusion-free cardiac reoperation in an 11-kg Jehovah's Witness child by use of a minimized cardiopulmonary bypass circuit.M Huebler, W Boettcher, A , A Koster et alTexas heart instit J.2007;34(1):108-11.

• Herein, we describe the design of a perfusion system for a complex cardiovascular reoperation in an 11-kg Jehovah's Witness patient. The goal of safe, transfusion-free surgery was achieved chiefly by minimizing the priming volume of the cardiopulmonary bypass circuit to 200 mL while providing adequate flow and standard safety features.

Transfusion-free cardiopulmonary bypass in Jehovah's Witness patients weighing less than 5 kg. M Huebler, W Boettcher, A , A Koster et alJ Extra Corpor Technol 2005 Sep;37(3):282-5

• We report the use of cardiopulmonary bypass (CPB) during open-heart surgery in three infants with a body weight of 4.5 kg, 3.5 kg, and 3.1 kg, respectively, without transfusion of blood components.

• A small-volume CPB circuit with a priming volume of 200 mL, including the arterial line filter, was designed to decrease the degree of hemodilution. A dedicated pediatric heart lung machine console with remote pump heads and intensive blood conservation efforts allowed the operation without the use of donor blood.

• The CPB circuits were primed with crystalloid solution only. The procedures were performed in normothermia or in moderate hypothermia.

• Pre-CPB hemoglobin levels were 10.8 g/dL, 10.6 g/dL, and 8.5 g/dL. The hemoglobin concentrations measured during CPB ranged from 5.9 to 6.5 g/dL, 6.4 to 6.8 g/dL, and 5.5 to 5.9 g/dL, respectively. The patients did not receive any blood or blood products during their entire hospital stay.

Transfusion-Free Complex Cardiac Surgery With Cardiopulmonary Bypass in a 3.55-Kg Jehovah’s Witness NeonateM Huebler, W Boettcher, A , A Koster et alPerfusion.2003 Nov;18(6):377-9.

• Prime volume 190 ml• TOF with absent pulmonary valve, LPA aneurysm• Operated at 7 days• No time to use EPO-starting Hb of 12.6• Pre CPB Hb 10.6. Lowest hb on CPB 6.4. weaned at 6.9• No MUF. Hemofilter prime vol 80 ml. H/E 20 ml• This procedure was augmented by short-term

vasoconstriction with repeated boluses of noradrenalin (0.2 mL of a 1:100 solution).

• ICU Hb 8.6. Epo started. Extubated day 5. Hb level day 7 10.6

• AOXCL 50’,CPB 104’

TAKE HOME MESSAGE

• Roller arterial head• Gravity drainage with VAVD as add on capability• M.U.F with the cardioplegia roller head through

the cardioplegia device• 3/16 inch line for Neonates 12 kgs and below• ½ inch line for adults and large children • Reduced prime by 50%• Reduced blood usage.• In the process for making process changes to

enhance blood conservation and ready us to initiate CPB on JW pts.

PROCESS IMPROVEMENTS

• Use pressor as well as volume to counter intra-operative hypotension

• Reduce OR time• Reduce bypass times• Accept lower hematocrits with acceptable

pressures/head sats• Treat the patient and not a number• Add a large ped oxygenator –Quadrox I

pediatric• Transfusion co-ordinator?