The paper by Al-Ruzzeh et al has the opportunity to add to the
already large amount of data published on the off pump versus on-pump as
it contributes a well constructed randomised controlled trial, albeit in
only 168 patients.
However the paper is let down by the lack of rigour imposed on the
method section of the paper. It is not possible to reproduce, nor fully
interpret this work as too many details are missing. The premise of
publication of science is to be able to reproduce the findings. There is
no such entity as “Standard bypass management included………”, in 2006. The
authors have not told us the type of membrane oxygenator, the type of
arterial line filter and pore size, whether a prebypass filter was in fact
used, how cooling to 32C was achieved, and more importantly how rewarming
was achieved, the type of tubing used in the circuit (coated biopassive
circuit or uncoated), and the type of pH management utilised on bypass.
Each of these factors may contibute to the genesis of clinical outcomes
following surgery utilising cardiopulmonaty bypass, and specifically to
the generation of neurocognitive outcomes.
The authors have recognisede the importance of some of these factors
in their discussion, citing the importance of rewarming rates (1) and pH
managment (2), however they have failed to provide the reader with detail
on their approach.
That the authors were able to show similar angiographic findings and
improved clinical outcomes, shorter hospital stay and improved
neurocogntive outcome in the off pump is significant, it is unfortunate
that detail of the cardiopulmonary bypass utilised is lacking.
1. Grigore A, Grocott H, Mathew J, Phillips-Bute B, Stanley T,
Butler A, et al. The rewarming rate and increased peak temperature alter
neurocognitive outcome after cardiac surgery. Anesth Analg 2002;94:4-10.
2. Murkin J, Martzke J, Buchan A, Bentley C, Wong C. A randomised
study of the influence of perfusion technique and pH management strategy
in 316 patients undergoing
coronary artery bypass surgery: neurologic and cognitive outcomes. J
Thorac Cardiovasc Surg 1995;110:349-62.
Competing interests:
None declared
Competing interests:
No competing interests
20 June 2006
Robert A Baker
Director Crdiac Surgery Research
Flinders Medical Centre, Bedford Park, Adelaide, South Australia 5042
Rapid Response:
Standard bypass: no longer a standard term
The paper by Al-Ruzzeh et al has the opportunity to add to the
already large amount of data published on the off pump versus on-pump as
it contributes a well constructed randomised controlled trial, albeit in
only 168 patients.
However the paper is let down by the lack of rigour imposed on the
method section of the paper. It is not possible to reproduce, nor fully
interpret this work as too many details are missing. The premise of
publication of science is to be able to reproduce the findings. There is
no such entity as “Standard bypass management included………”, in 2006. The
authors have not told us the type of membrane oxygenator, the type of
arterial line filter and pore size, whether a prebypass filter was in fact
used, how cooling to 32C was achieved, and more importantly how rewarming
was achieved, the type of tubing used in the circuit (coated biopassive
circuit or uncoated), and the type of pH management utilised on bypass.
Each of these factors may contibute to the genesis of clinical outcomes
following surgery utilising cardiopulmonaty bypass, and specifically to
the generation of neurocognitive outcomes.
The authors have recognisede the importance of some of these factors
in their discussion, citing the importance of rewarming rates (1) and pH
managment (2), however they have failed to provide the reader with detail
on their approach.
That the authors were able to show similar angiographic findings and
improved clinical outcomes, shorter hospital stay and improved
neurocogntive outcome in the off pump is significant, it is unfortunate
that detail of the cardiopulmonary bypass utilised is lacking.
1. Grigore A, Grocott H, Mathew J, Phillips-Bute B, Stanley T,
Butler A, et al. The rewarming rate and increased peak temperature alter
neurocognitive outcome after cardiac surgery. Anesth Analg 2002;94:4-10.
2. Murkin J, Martzke J, Buchan A, Bentley C, Wong C. A randomised
study of the influence of perfusion technique and pH management strategy
in 316 patients undergoing
coronary artery bypass surgery: neurologic and cognitive outcomes. J
Thorac Cardiovasc Surg 1995;110:349-62.
Competing interests:
None declared
Competing interests: No competing interests