Figures
- FIGURE 1
Histograms demonstrating in-hospital mortality in medical patients according to quintiles of a) APACHE II (Acute Physiology and Chronic Health Evaluation II) score, b) platelet count, c) serum sodium level, d) age, e) oxygen saturation measure by pulse oximetry (SpO2)/inspiratory oxygen fraction (FiO2) ratio and f) lactate. Each bar represents 20% of the population for that parameter.
- FIGURE 2
OPALS score. Risk of hospital mortality in medical patients based on number of adverse single risk factors. OPALS: oxygen (oxygen saturation measured by pulse oximetry/inspiratory oxygen fraction ratio) ≤185; platelets ≤196×109·L−1; age ≥37.5 years; lactate ≥2.45 mmol·L−1; sodium ≤130.5 mmol·L−1).
- FIGURE 3
Long-term survival of patients discharged from hospital following their first presentation to critical care. p=0.008 medical versus surgical, p=0.001 medical versus obstetric, p=0.073 surgical versus obstetric.
Tables
- TABLE 1
Baseline characteristics
Subjects n 242 Age years 52.5 (17–87) Female 68.2 PH diagnostic group 1 Pulmonary arterial hypertension 162 (66.9) Idiopathic/heritable/drugs and toxins 96 (59.3) Connective tissue disease associated 40 (24.7) Congenital heart disease associated 18 (11.1) Others 8 (4.9) 2 PH due to left heart disease 13 (5.3) 3 PH due to lung disease/chronic hypoxia 14 (5.8) 4 Chronic thromboembolic PH 39 (16.1) 5 Unclear/multifactorial 14 (5.8) WHO functional class# I 1.4 II 14.9 III 70.2 IV 13.5 ISWD m# 190 (0–1020) Pulmonary haemodynamics¶ mRAP mmHg 10.0 (1–34) mPAP mmHg 47 (14–74) PAWP mmHg 10 (0–33) CO L·min−1 4.7 (1.87–14.2) CI L·min−1·m−2 2.6 (1.2–6.0) PVR dyn·s−1·cm−5 561 (84–2400) SvO2 % 65 (35–86) Data are presented as median (min–max), % or n (%), unless otherwise stated. PH: pulmonary hypertension; WHO: World Health Organization; ISWD: incremental shuttle walk distance; mRAP: mean right atrial pressure; mPAP: mean pulmonary artery pressure; PAWP: pulmonary arterial wedge pressure; CO: cardiac output; CI: cardiac index; PVR pulmonary vascular resistance; SvO2: mixed venous oxygen saturations. #: 2 weeks to 18 months prior to admission; ¶: nearest prior to admission.
- TABLE 2
Patient characteristics on critical care admission
Subjects Patient group Medical 167 (69.0) Surgical 50 (20.7) Obstetric 25 (10.3) Main reason for admission Medical patients Isolated heart failure 63 (37.7) Respiratory failure/chest sepsis 44 (26.4) Sepsis (other) 13 (7.8) Renal failure 12 (7.2) Arrhythmia 14 (8.4) PE 6 (3.6) Other 15 (9) Surgical patients Peri-operative (planned): 42 (84) Orthopaedic 18 (36) Hernia repair 4 (8) Other general surgery 7 (14) Urological 3 (6) Miscellaneous# 10 (20) Peri-operative (emergency): 8 (16) Urological 3 (6) Neurosurgical 2 (4) General 1 (2) Gynaecological 1(2) Orthopaedic 1 (2) Obstetric patients Peri-partum 19 (76) Other pregnancy related causes 6 (24) Physiological parameters Medical¶ Surgical/obstetric+ p-value APACHE II 15.0 (2–31) 10 (2–21) <0.001 Heart rate 99 (48–163) 80 (49–126) <0.001 mSAP mmHg 79 (41–140) 85 (56–117) 0.001 Respiratory rate 24 (12–52) 17 (9–39) <0.001 SpO2/FiO2 ratio 168 (68–467) 278 (108–467) <0.001 PaO2 kPa 10.4 (4.3–28.9) 13.7 (6.9–25.3) <0.001 PaO2/FiO2 ratio 22 (5–72) 49 (9–89) <0.001 CVP mmHg 18 (2–35) 8 (3–22) <0.001 Glasgow Coma Scale 15 (3–15) 15 (13–15) 0.010 pH 7.43 (6.98–7.54) 7.41 (7.31–7.51) 0.253 Base excess mmol·L−1 −2.6 (−20.4–26.9) −1.75 (−8.5–7.2) 0.219 Lactate mmol·L−1 1.2 (0.4–14.1) 1.0 (0.5–2.4) 0.006 Sodium mmol·L−1 135 (113–147) 138 (127–146) <0.001 Urea mmol·L−1 10.2 (2.5–59.4) 3.9 (1.2–16.1) <0.001 Creatinine μmol·L−1 117 (3–891) 61.5 (26–181) <0.001 Bilirubin μmol·L−1 17 (1–131) 11 (2–55) <0.001 AST IU·L−1 27 (6–4733) 18 (11–150) <0.001 CRP mg·L−1 38 (1–471) 11.6 (0.3–340) <0.001 Haemoglobin g·L−1 119 (53–204) 113 (86–166) 0.027 Platelets ×109·L−1 194 (32–859) 202 (73–448) 0.297 Data are presented as n (%) or median (min–max), unless otherwise stated. Comparisons made using Mann–Whitney U-test, medical versus surgical/obstetric groups. PE: pulmonary embolism; APACHE II: Acute Physiology and Chronic Health Evaluation II; mSAP: mean systemic arterial pressure; SpO2: oxygen saturation measured by pulse oximetry; FiO2: inspiratory oxygen fraction; PaO2: arterial oxygen tension; CVP: central venous pressure; AST: aspartate aminotransferase; CRP: C-reactive protein. #: neurosurgery, spinal surgery, vascular, breast and gynaecological; ¶: n=167; +: n=75.
- TABLE 3
Critical care and hospital survival according to patient group and intensive care unit (ICU) therapy
N ICU survival Hospital survival 90-day survival 1-year survival N# 5-year survival# Overall 242 190 (78.5) 169 (69.8) 158 (65.3) 132 (54.5) 146 45 (30.8) Patient group Medical 167 120 (71.9) 99 (59.3) 91 (54.5) 68 (40.7) 114 26 (22.8) Surgical 50 47 (94.0) 47 (94.0) 45 (90) 42 (84) 19 10 (52.6) Obstetric 25 23 (92.0) 23 (92.0) 22 (88) 22 (88) 13 9 (69.2) PH group 1 PAH 162 127 (78.4) 115 (71.0) 107 (66.0) 90 (55.6) 95 32 (33.7) 2 PH due to left heart disease 13 11 (84.6) 10 (76.9) 10 (76.9) 8 (61.5) 7 2 (28.6) 3 PH due to lung disease/hypoxia 14 9 (64.3) 8 (57.1) 7 (50) 6 (42.9) 10 0 (0) 4 Chronic thromboembolic PH 39 34 (87.2) 29 (74.4) 27 (69.2) 24 (61.5) 26 10 (38.5) 5 Unclear/multifactorial 14 9 (64.3) 7 (50) 7 (50) 4 (28.6) 8 1 (12.5) ICU therapy (medical patients only) CPAP as highest level of ventilatory support 53 34 (64.1) 27 (50.9) 25 (47.1) 20 (37.7) 33 2 (6.1) NPPV as highest level of ventilatory support 15 9 (60) 6 (40) 5 (33.3) 3 (20) 10 0 (0) IPPV as highest level of ventilatory support 9 3 (33.3) 1 (11.1) 1 (11.1) 1 (11.1) 9 0 (0) CRRT 22 17 (77.3) 11 (50.0) 9 (40.9) 7 (31.8) 20 5 (25) Vasopressors received 49 23 (46.9) 16 (32.7) 15 (30.6) 11 (22.4) 28 3 (10.7) Inotropes received 37 17 (45.9) 13 (35.1) 12 (32.4) 7 (18.9) 29 3 (10.3) Prostaglandins (intravenous) received 113 78 (69.0) 68 (60.2) 61 (54) 45 (39.8) 73 18 (24.7) Data are presented as n (%), unless otherwise stated. PH: pulmonary hypertension; PAH: pulmonary arterial hypertension; CPAP: continuous positive airway pressure; NPPV: non-invasive positive pressure ventilation: IPPV: invasive positive pressure ventilation; CRRT: continuous renal replacement therapy. #: patients admitted prior to 31 December 2013 for whom 5 years of survival data is available.
- TABLE 4
Medical patients: univariate predictors of hospital mortality
Variable N OR (95% CI) p-value Age years 167 1.02 (1.01–1.04) 0.005 Female (ref.) 167 0.914 (0.481–7.738) 0.784 PH group 167 0.704 1 Pulmonary arterial hypertension Ref. 2 PH due to left heart disease 1.568 (0.303–8.120) 0.592 3 PH due to lung disease/hypoxia 1.307 (0.376–4.541) 0.674 4 Chronic thromboembolic PH 0.882 (0.359–2.169) 0.785 5 Unclear/multifactorial 2.195 (0.656–7.350) 0.202 Admission reason# 167 0.03 Heart failure Ref. Ref. Respiratory failure/chest sepsis 0.554 (0.254–1.208) 0.138 Sepsis (other) 0.356 (0.099–1.277) 0.113 Pulmonary embolism 0.800 (0.150–4.274) 0.794 Arrhythmia 0.133 (0.028–0.646) 0.012 Renal failure 0.267 (0.066–1.079) 0.064 Other 0.200 (0.051–0.779) 0.020 ISWD 102 0.998 (0.995–1.001) 0.242 APACHE II 137 1.180 (1.095–1.270) <0.001 Heart rate 166 1.011 (0.995–1.028) 0.190 mSAP mmHg 163 0.983 (0.964–1.003) 0.100 Respiratory rate 167 1.046 (1.005–1.087) 0.026 SpO2 % 167 0.984 (0.939–1.030) 0.482 FiO2 165 5.896 (1.445–24.061) 0.013 PaO2 kPa 142 0.959 (0.888–1.036) 0.292 SpO2/FiO2 ratio 134 0.997 (0.993–1.001) 0.114 PaO2/FiO2 ratio 134 0.983 (0.959–1.008) 0.187 Central venous pressure mmHg 54 1.096 (1.021–1.177) 0.011 Glasgow Coma Scale 138 0.727 (0.539–0.980) 0.036 pH 148 0.007 (0.000–0.393) 0.016 Base excess mEq·L−1 147 0.933 (0.886–0.984) 0.01 Lactate mmol·L−1 141 1.425 (1.117–1.817) 0.004 Serum sodium mmol·L−1 157 0.937 (0.884–0.993) 0.027 Serum urea mmol·L−1 156 12.7 (4.37–80.2) 0.001 Serum creatinine µmol·L−1 155 1.005 (1.001–1.009) 0.013 Total bilirubin µmol·L−1 143 6.08 (2.97–19.8) 0.022 AST IU·L−1 123 0.999 (0.995–1.002) 0.456 CRP mg·L−1 141 1.005 (1.000–1.009) 0.054 Haemoglobin g·L−1 157 0.990 (0.978–1.003) 0.123 Platelets ×109·L−1 156 0.997 (0.994–1.000) 0.033 Right atrial pressure mmHg 109 1.044 (0.990–1.101) 0.108 Mean PAP mmHg 114 1.005 (0.973–1.037) 0.775 PAWP mmHg 102 1.000 (0.919–1.088) 1.000 Cardiac output L·min−1 110 0.909 (0.743–1.112) 0.352 Cardiac index L·min−1·m−2 104 0.838 (0.584–1.201) 0.335 PVR dyn·s−1·cm−5 99 1.000 (0.999–1.001) 0.482 SvO2 % 102 0.966 (0.929–1.005) 0.087 Variables either at most recent review prior to admission (Right heart catheter data, ISWD at 2 weeks to 18 months prior to admission) or at critical care admission (e.g. laboratory tests and physiological observations). Bold indicates statistical significance. PH: pulmonary hypertension; ISWD: incremental shuttle walking distance; APACHE II: Acute Physiology and Chronic Health Evaluation II; mSAP: mean systemic arterial pressure; SpO2: oxygen saturation measured by pulse oximetry; FiO2: inspiratory oxygen fraction; PaO2: arterial oxygen tension; AST: aspartate aminotransferase; CRP: C-reactive protein; PAP: pulmonary artery pressure; PAWP: pulmonary arterial wedge pressure; PVR: pulmonary vascular resistance; SvO2: mixed venous oxygen saturation. #: main indication for critical care admission.
- TABLE 5
Medical patients: multivariate predictors of hospital mortality
Variable OR (95% CI) p-value Model 1# APACHE II per point 1.148 (1.052–1.253) 0.002 Sodium mmol·L−1 0.927 (0.864–0.996) 0.038 Platelets ×109·L−1 0.997 (0.993–1.000) 0.052 SpO2/FiO2 ratio 0.997 (0.992–1.001) 0.104 Bilirubin IU·L−1 0.997 (0.970–1.024) 0.806 Creatinine µmol·L−1 0.999 (0.995–1.004) 0.790 Lactate mmol·L−1 1.292 (0.983–1.700) 0.067 Model 2¶ Age years 1.045 (1.018–1.073) 0.001 Sodium mmol·L−1 0.901 (0.836–0.971) 0.007 Platelets ×109·L−1 0.996 (0.993–1.000) 0.038 SpO2/FiO2 ratio 0.995 (0.991–0.999) 0.020 Total bilirubin µmol·L−1 0.993 (0.966–1.021) 0.620 Creatinine µmol·L−1 1.002 (0.998–1.006) 0.333 Lactate mmol·L−1 1.562 (1.181–2.066) 0.002 APACHE II: Acute Physiology and Chronic Health Evaluation II; SpO2: oxygen saturation measured by pulse oximetry; FiO2: inspiratory oxygen fraction. #: incorporating APACHE II; ¶: excluding APACHE II.
