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Epidemiology of obstetric critical care

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In the last 20 years, in developed countries, maternal mortality rates have fallen such that analysis of cases of severe maternal morbidity is necessary to provide sufficient numbers to give a clinically relevant assessment of the standard of maternal care. Different approaches to the audit of severe maternal morbidity exist, and include need for intensive care, organ system dysfunction and clinically defined morbidities. In both developed and developing countries, the dominant causes of severe morbidity are obstetric haemorrhage and hypertensive disorders. In some low-resource regions, obstructed labour and sepsis remain significant causes of severe maternal morbidity. The death to severe morbidity ratio may reflect the standard of maternal care. Audits of severe maternal morbidity should be complementary to maternal mortality reviews.

Section snippets

Definitions

Maternal obstetric morbidity may be defined as morbidity from any cause related to or aggravated by the pregnancy or its management, but not from accidental or incidental causes.11 Mantel et al12 defined severe maternal morbidity as ‘a very ill pregnant or recently delivered woman who would have died had it not been but luck and good care was on her side’. They also use the term ‘severe acute maternal morbidity’.12

The term ‘near-miss’ has been borrowed from the aviation industry to describe

Prevalence

The rates of severe maternal morbidity tend to parallel maternal death rates. Prevalence also depends on the definition of morbidity. In developed countries, morbidity rates range from 0.05 to 1.7%.13, 14 In countries with low resources, prevalence ranges from 0.6 to 8.5%.15, 16 Say et al.17, in a systematic review of 30 studies in 2004, found that within the different definitions of morbidity, the prevalence varied between 0.8% and 8.2% for disease-specific criteria, 0.4% and 1.1% for

Classification

Many different classifications of severe maternal morbidity have arisen in the last 15 years and these will be considered below.

Severe morbidity audit in low-resource settings

A number of audits included in Table 1, Table 2, Table 3, Table 4 are from low-resource settings. In general, the main causes of morbidity are the same, haemorrhage and hypertensive disorders, but the death to morbidity ratio tends to be lower compared with developed countries. Two studies from Nigeria54 and West Africa55 showed that in addition to haemorrhage and hypertension, obstructed labour and sepsis remain significant risks to the mother. In the Nigerian study, there were 13 deaths out

Trends

There is reason to believe that severe maternal morbidity may increase in developed countries.56 This is likely because of the changing demographics of pregnant women in developed countries with increasing maternal age, increasing caesarean section rates and obesity.57, 58 The most recent UK Confidential Enquiry into Maternal Deaths (2003–2005) implicated obesity in almost half of the deaths.59 In addition, assisted reproductive technology has increased the number of multiple pregnancies,

Preparedness for obstetric critical care

Obstetrics has always lent itself to audit and measurement. The main causes of maternal mortality and morbidity are known. National, regional and hospital audits will help delineate the main local threats, but in almost all studies of severe maternal morbidity, whether they be based on ICU admissions, organ system dysfunction or clinically defined morbidities, be they in developed or developing countries, the dominant obstetric causes are haemorrhage and severe pre-eclampsia/eclampsia.

References (69)

  • E.L. Simpson et al.

    Venous thromboembolism in pregnancy and the puerperium: incidence and additional risk factors from a London perinatal database

    British Journal of Obstetrics and Gynaecology

    (2001)
  • W. Lee et al.

    Maternal and perinatal outcomes of eclampsia: Nova Scotia, 1981–2000

    Journal of Obstetrics and Gynaecology Canada

    (2004)
  • T.M. Jenkins et al.

    Mechanial ventilation in an obstetric population: characteristics and delivery rates

    American Journal of Obstetrics and Gynecology

    (2003)
  • M.H. Bouvier-Colle et al.

    Case-control study of risk factors for obstetric patients' admission to intensive care units

    European Journal of Obstetrics, Gynecology, and Reproductive Biology

    (1997)
  • C.A. Cameron et al.

    Trends in postpartum haemorrhage

    Australian and New Zealand Journal of Public Health

    (2006)
  • M. Waterstone et al.

    Postnatal morbidity after childbirth and severe obstetric morbidity

    British Journal of Obstetrics and Gynaecology

    (2003)
  • J.M. Guise

    Anticipating and responding to obstetric emergencies

    Best Practice & Research. Clinical Obstetrics & Gynaecology

    (2007)
  • G. Penney et al.

    Do clinical guidelines enhance safe practice in obstetrics and gynaecology?

    Best Practice & Research. Clinical Obstetrics & Gynaecology

    (2007)
  • T.F. Baskett

    Surgical management of severe obstetric haemorrhage: experience with an obstetric haemorrhage equipment tray

    Journal of Obstetrics and Gynaecology Canada

    (2004)
  • M.H. Hall

    Near misses and severe maternal morbidity

  • J.O. Drife

    Maternal ‘near-miss’ reports?

    BMJ

    (1993)
  • S. Bewley et al.

    ‘Near-miss’ obstetric inquiry

    Journal of Obstetrics and Gynaecology

    (1997)
  • Special Report on Maternal Mortality and Severe Morbidity in Canada

    (2004)
  • M. Harmer

    Maternal mortality – is it still relevant?

    Anaesthesia

    (1997)
  • D.L. Hoyert et al.

    Maternal mortality, United States and Canada, 1982–1997

    Birth

    (2000)
  • K. Wildman et al.

    Maternal mortality as an indicator of obstetric care in Europe

    British Journal of Obstetrics and Gynaecology

    (2004)
  • S.E. Geller et al.

    Reliability of a preventability model in maternal death and morbidity

    American Journal of Obstetrics and Gynecology

    (2007)
  • R.C. Pattinson et al.

    Critical incident audit and feedback to improve perinatal and maternal mortality and morbidity

    Cochrane Database of Systematic Reviews

    (2005)
  • F. Parauk et al.

    Severe obstetric morbidity

    Current Opinion in Obstetrics and Gynecology

    (2001)
  • G. Mantel et al.

    Severe acute maternal morbidity: a pilot study of a definition of a ‘near-miss’

    British Journal of Obstetrics and Gynaecology

    (1998)
  • C. Fitzpatrick et al.

    ‘Near-miss’ mortality

    Irish Medical Journal

    (1992)
  • K. Mjahed et al.

    Obstetric patients in a surgical intensive care unit: prognostic factors and outcome

    Journal of Obstetrics and Gynaecology

    (2006)
  • V. Filippi et al.

    Maternity wards or emergency obstetric rooms? Incidence of near-miss events in African hospitals

    Acta Obstetricia et Gynecologica Scandinavica

    (2005)
  • L. Say et al.

    WHO systematic review of maternal morbidity and mortality: the prevalence of severe acute maternal morbidity (near miss)

    Reproductive Health

    (2004)
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