Perioperative Mortality in New Zealand Report
Questions and Answers
February 2012
Embargoed to 10am, 15 February 2012
What does the Perioperative Mortality Review Committee (POMRC) do?
POMRC was established in 2010. It is an independent mortality review committee that
advises the Health Quality & Safety Commission on how to reduce the number of
perioperative deaths in New Zealand.
The aim of the Committee is to review and report on national perioperative mortality with a
view to reducing these deaths and continuously improving the quality of the health system
and, therefore, outcomes for patients. The Committee will also develop strategic plans and
methodologies to reduce both illness and death.
Perioperative deaths are:
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a death that occurred after an operative procedure
o within 30 days
o after 30 days but before discharge from hospital to home or a rehabilitation
facility.
a death that occurred whilst under the care of a surgeon in hospital even though an
operation was not undertaken.
What is the purpose of this report?
This is POMRC’s first report and the first time data has been examined in this way. Its
purpose is to help gain a better understanding of deaths that occur in the days and weeks
following surgery and anaesthesia, to help reduce harm to patients.
The report provides an overview of what is known about perioperative mortality in New
Zealand, identifies gaps and is a starting point for the development of a national
perioperative mortality review system.
While in many cases the operation itself played no part in the patient’s death, in a small
number of cases there will be lessons that can be learned to help improve the quality of
health care provided in New Zealand.
How should the information in this report be used?
This report has valuable information for patients, and surgeons and anaesthetists. It helps us
better understand the risk of death for particular operations using New Zealand figures,
rather than figures from overseas which is all we have had up until now. For example,
doctors will be able to tell patients that ‘x’ percentage of patients died after that operation,
giving them a better indication of the risks of the planned operation.
How can patients get this information?
The Health Quality & Safety Commission will be providing this information to all hospitals in
the expectation doctors will use it when talking to patients about the risks involved in
particular operations. People will also be able to get this information directly from the
Commission’s website.
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POMRC is also interested in hearing patients’ views on what type of information about risk
they need from their doctor in order to make an informed choice about surgery. This
feedback can be sent to Deon York at the Health Quality & Safety Commission:
deon.york@hqsc.govt.nz, PO Box 25496, Wellington, phone 04 901 6060.
What were the report’s main findings and recommendations
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Between 4000 and 5000 patients die following any form of surgical procedure and
anaesthesia each year in New Zealand. In many cases, the operation itself played no
part in the patient’s death.
Overall mortality rates for the areas considered (hip and knee arthroplasty, colorectal
resection, cataract surgery and anaesthesia) were comparable with similar
international reports.
For hip replacement surgery, 0.24 percent of patients died within 30 days of
admission for an elective (routine) operation. For patients admitted as an emergency,
usually following a hip fracture, 7.3 percent died within 30 days of surgery.
For elective colorectal resection, 2.1 percent of patients died within 30 days of
surgery. For acute colorectal operations, the mortality rate at 30 days was 9.8
percent.
0.2 percent of patients admitted for cataract surgery died within 30 days of the
operation, with most deaths occurring after the person had been discharged from
hospital. Heart attacks and other types of heart disease were most frequently listed
as the cause of death.
Data on more than 1.1 million general anaesthetics were reviewed (68 percent of
these being elective procedures). Following 792,614 general anaesthetics, there
were 177 deaths (0.02 percent), with just under half due to heart attacks or other
cardiovascular causes.
The report recommends building upon existing data collections to enable the
establishment of a whole-of-health care system mortality review process. The work of
POMRC over the coming years will drive these developments.
The report also suggests a formal memorandum of understanding between POMRC
and Coronial Services to ensure access to data, working closely with the National
Health Board to enhance and standardise existing mortality data collections.
POMRC would also like to see mandatory submission of data by all health care
facilities.
Why do people die following surgery and anaesthesia?
This report estimates that between 4000 and 5000 people die within 30 days of surgery or
anaesthesia each year. Of these patients:
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some are already quite unwell when they have surgery. For example, someone who
needs an emergency operation because they have fallen and broken their hip
many are older. For example, in 2005–2009 only 4 percent of patients aged 45–64
died after emergency colorectal resection while 19 percent of patients aged 80+
years did so
some may already have an advanced disease or illness, such as cancer, that is
discovered as the result of a diagnostic operation
many deaths following surgery are due to heart attacks, heart failure, or stroke.
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How reliable is the data in this report?
This is the first report on perioperative mortality in New Zealand, and the most accurate data
available has been used. Data used is from the National Minimum Dataset and the National
Mortality Collection. Both these datasets are maintained by the Ministry of Health.
However, the figures should be treated as an estimate as they don’t include data from
private hospitals. Continuing to increase the accuracy of data is a priority for POMRC.
From this data, can you tell what the most risky surgical procedure is?
In general, the risk involved in surgical procedures is linked more to factors related to the
person having the surgery, than the type of surgery. For example, risk is greater for older
people, people who are very unwell, and people having emergency surgery, irrespective of
what the procedure is.
This report focuses on four areas only: hip and knee arthroplasty, colorectal resection,
cataract surgery and anaesthesia. Future reports will look at other areas. We do know from
the areas considered in this report that emergency procedures are more risky than planned
(elective) procedures.
Is this data available broken down into specific DHBs?
No, the data is from the National Minimum Dataset and the National Mortality Collection,
which combines data from DHBs.
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