Variability in intensive care unit admission among pregnant and postpartum women in Canada: a nationwide population-based observational study

Abstract

BackgroundPregnancy-related critical illness results in approximately 300,000 deaths globally each year. The objective was to describe the variation in ICU admission and the contribution of patient- and hospital-based factors in ICU admission among acute care hospitals for pregnant and postpartum women in Canada.MethodsA nationwide cohort study between 2004 and 2015, comprising all pregnant or postpartum women admitted to Canadian hospitals. The primary outcome was ICU admission. Secondary outcomes were severe maternal morbidity (a potentially life-threatening condition) and maternal death (during and within 6 weeks after pregnancy). The proportion of total variability in ICU admission rates due to the differences among hospitals was described using the median odds ratio from multi-level logistic regression models, adjusting for individual hospital clusters.ResultsThere were 3,157,248 identifiable pregnancies among women admitted to 342 Canadian hospitals. The overall ICU admission rate was 3.2 per 1000 pregnancies. The rate of severe maternal morbidity was 15.8 per 1000 pregnancies, of which 10% of women were admitted to an ICU. The most common severe maternal morbidity events included postpartum hemorrhage (n = 16,364, 0.52%) and sepsis (n = 11,557, 0.37%). Of the 195 maternal deaths (6.2 per 100,000 pregnancies), only 130 (67%) were admitted to ICUs. Patients dying in hospital, without admission to ICU, included those with cardiovascular compromise, hemorrhage, and sepsis. For 2 pregnant women with similar characteristics at different hospitals, the average (median) odds of being admitted to ICU was 1.92 in 1 hospital compared to another. Hospitals admitting the fewest number of pregnant patients had the highest incidence of severe maternal morbidity and mortality. Patient-level factors associated with ICU admission were maternal comorbidity index (OR 1.88 per 1 unit increase, 95%CI 1.86–1.99), urban residence (OR 1.09, 95%CI 1.02–1.16), and residing at the lowest income quintile (OR 1.44, 95%CI 1.34–1.55).ConclusionsMost women who experience severe maternal morbidity are not admitted to an ICU. There exists a wide hospital-level variability in ICU admission, with patients living in urban locations and patients of lowest income levels most likely to be admitted to ICU. Cardiovascular compromise, hemorrhage, and sepsis represent an opportunity for improved patient care and outcomes.

Maternal intensive care unit admission as an indicator of severe acute maternal morbidity: A population-based study

“…The number of intermediate care units may have increased in France since the 2012-2013-study period, and maternal admissions in these units may be more frequent now [36]. Indications for maternal ICU admission may differ across countries, because of specific organization systems, especially billing, and ICU bed availability [13,37,38]; however, the incidence of maternal ICU admissions we found was similar as that reported in other high-resource countries [8,13,39].…”

“…Maternal admission to an intensive care unit (ICU) is commonly used as a single indicator of severe acute maternal morbidity [3][4][5][6][7][8]. However, maternal ICU admission depends on not only patient severity but also care organization and local practices [9][10][11][12][13]. Consequently, women admitted to the ICU could present heterogeneous levels of severity in maternal morbidity.…”

Obstetric admissions to intensive care units in Australia and New Zealand: a registry‐based cohort study

“…[5][6][7][8][9]11,12,27 However, the crude hospital mortality rate in Australia (0.6%) and New Zealand (1.0%) was lower than that reported from Canada (1.3%), France (1.3%), Maryland (1.8%), the UK (1.9%), Beijing (1.9%) and the Netherlands (3.5%). [5][6][7][8][9][10][11]27 In most of these reports, a greater proportion of patients were intubated and a higher proportion of deaths were due to obstetric-related disease. It is important to recognise the different case definitions used, and that risk-adjusted mortality rates are not available.…”

“…7 The proximate cause of death was unable to be determined, and the ICU admission diagnosis was used to indicate disease categories associated with death. We were 103 (10) 98 (8) 133 (11) 135 (9) 137 (9) 165 (10) 178 (10) 228 (12) 254 (12) 280 (13) 1711 (11) Pre-eclampsia 105 (10) 75 (6) 102 (8) 125 (9) 141 (9) 166 (11) 157 (9) 168 (9) 199 (9) 215 (10) 1453 (9) Non-obstetric diagnoses,n (%) Respiratory 87 (8) 154 (13) 113 (9) 125 (9) 102 7105 7120 7126 7144 7123 (6) 1199 7Cardiovascular 132 (12) 118 (10) 106 (8) 106 (7) 69 (4) 74 (5) 94 5100 5108 (5) 105 (5) 1012 6Sepsis 29 331 352 (4) 60 (4) 71 (5) 74…”

Acute kidney injuries induced by thrombotic microangiopathy following severe hemorrhage in puerperants: A case series and literature review

“…However, TMAs could also be triggered by non-pregnancy related conditions such as thrombotic thrombocytopenic purpura (TTP), as well as pregnancy-related conditions, such as preeclampsia with severe features or eclampsia with HELLP (haemolysis, elevated liver enzymes, and low platelets) syndrome [12][13][14]. TMA is associated with adverse maternal and fetal outcomes due to the development of ESRD and ultimately leading to increased maternal mortality [15,16]. Three puerperant patients were recruited in this study with severe hemorrhage and AKI, and following renal histopathology, TMA was found to coexist with ATN.…”