Page 37 - ANZCP Gazette November 2021

Steel and Bui
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Tally of like reasoning
Respondents reasons for adding NaHCO3 to Plasma-Lyte base
Dose Of NaHCO3
6
to correct for pH / avoid prime acidosis
30-80ml of 8.4%
3
for use with CDI/ avoid poisoning CDI cuvette
10-25ml of 8.4%
2
to ‘buffer ’the solution
50ml of 8.4%
1
added if preop ABG has HCO3 < 22
30ml of 8.4%
1
to raise pCO2 to physiological level to initiate CPB
25ml of 8.4%
Figure 10. Tally of reasons for using NaHCO3 in Plasma-Lyte.
Tally of like reasoning
Respondents reasons for adding Mannitol to the perfusion prime
3
as an osmotic diuretic
3
to help maintain kidney function
2
contributes to osmotic pressure
2
as an oxygen free radical scavenger
1
for DHCA
1
for poor preop creatinine
1
to reduce the volume load of the patient
1
claimed Plasma-Lyte was hypo-osmotic
Figure 11. Tally of reasons for using mannitol in prime solutions.
The selection of prime base solution for most units seems to be historical (20 respondents replied that was the solution they ‘have always’ used). Many, but not all, respondents then provided supportive reasons for their selection indicating they still supported this choice. The primary reason Plasma-Lyte was selected as a base solu- tion was that it was more physiologically balanced (iso- tonic) and contained no lactate. The primary reason Hartmann’s was used was historical yet still deemed appropriate. 8
Since this survey was conducted, Weinberg et al. have published an investigation on the incidence of either a Plasma-Lyte or Hartmann’s prime solution in causing metabolic acidosis on bypass. The conclusion to this study was that neither solution produced a meta- bolic acidosis at the bypass time of 60 minutes. It could be concluded, based on the current level of evidence and consensus, that both Plasma-Lyte and Hartmann’s solu- tions are suitable priming solutions for Australia in terms of metabolic acidosis.
In 12 adult Australian units (performing 4,850 cases annually), heparin is the only additive to their base solu- tion. While another four units (1,670 patients per year) added albumin ‘as required’ to their heparin and base solution. Thus, up to 30% of cases may receive only hep- arin as an additive to their prime base solution. All other cases had various combinations of sodium bicarbonate, mannitol and albumin. The results also indicate a meas- ure of patient-centred perfusion by some Australian units. These units add additives as indicated by the patient’s preoperative factors or by the procedure rather than adding them routinely.
Albumin was a popular addition to prime solutions in Australia. A total of 31 units (51%) routinely add albumin, with another 11 (17%) adding it ‘if required’. These 11 units would add albumin based on patients’ factors (such as size, age, history and hypoalbumine- mia) or length of procedure. The 31 units adding albu- min routinely predominantly do so to coat their circuits. This is in addition to Australian units having widespread
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