Background
Methods
Study population
Data collection
Microbiological examinations
Anti-infective therapy
Outcome
Statistical analysis
Results
Patient characteristics
Variables | All patients (n = 343) | Bacteraemic patients (n = 64) | Patients without bacteraemia (n = 279) | Odds ratio | 95% CI | p value |
---|---|---|---|---|---|---|
Demographic characteristics and underlying diseases | ||||||
Age (years), median (IQR) | 62 (49–73) | 63 (52–74) | 61 (48–73) | 0.92 | (0.53–1.58) | 0.56 |
Male gender, n (%) | 184 (54) | 32 (50) | 152 (54) | 0.83 | (0.49–1.44) | 0.52 |
Fatal underlying disease, n (%) | 110 (32) | 29 (45) | 81 (29) | 2.02 | (1.16–3.53) | 0.012 |
Immunosuppression, n (%) | 121 (35) | 37 (59) | 84 (30) | 3.25 | (1.85–5.71) | < 0.001 |
Diabetes mellitus, n (%) | 59 (17) | 12 (19) | 47 (17) | 1.14 | (0.56–2.29) | 0.72 |
Cancer, n (%) | 126 (37) | 35 (55) | 91 (33) | 2.49 | (1.43–4.33) | < 0.001 |
Initial surgery | ||||||
Upper gastrointestinal tract surgery, n (%) | 150 (44) | 26 (41) | 124 (44) | 0.85 | (0.49–1.48) | 0.57 |
Septic or contaminated surgery, n (%) | 123 (36) | 25 (42) | 98 (37) | 1.20 | (0.68–2.12) | 0.53 |
Emergency procedure, n (%) | 135 (39) | 22 (34) | 113 (41) | 0.77 | (0.43–1.35) | 0.37 |
Antibiotics before reoperation for PIAI, n (%) | 215 (63) | 43 (67) | 172 (62) | 1.25 | (0.70–2.22) | 0.45 |
Interval between initial surgery and reoperation (days), median (IQR) | 7 (4–12) | 8 (4–15) | 7 (4–11) | 1.09 | (0.63–1.89) | 0.25 |
Severity criteria at the time of reoperation | ||||||
SAPS II score, median (IQR) | 47 (35–59) | 50 (38–63) | 47 (34–58) | 0.89 | (0.52–1.54) | 0.076 |
SOFA score, median (IQR) | 8 (4–10) | 8 (6–10) | 7 (4–10) | 1.10 | (0.59–1.75) | 0.034 |
Haemodynamic failurea, n (%) | 224 (65) | 46 (73) | 178 (64) | 1.53 | (0.83–2.81) | 0.16 |
Respiratory failurea, n (%) | 154 (45) | 30 (48) | 124 (44) | 1.13 | (0.65–1.96) | 0.65 |
Renal failurea, n (%) | 83 (24) | 16 (25) | 67 (24) | 1.05 | (0.56–1.98) | 0.86 |
Source of postoperative peritonitis and surgical observations | ||||||
Generalised infection, n (%) | 79 (23) | 20 (31) | 59 (21) | 1.69 | (0.92–3.09) | 0.08 |
Gastroduodenal source of infection, n (%) | 74 (22) | 11 (17) | 63 (23) | 0.71 | (0.35–1.44) | 0.34 |
Small bowel source of infection | 88 (26) | 13 (20) | 75 (27) | 0.69 | (0.35–1.34) | 0.27 |
Colonic or rectal source of infection, n (%) | 97 (28) | 20 (31) | 77 (28) | 1.19 | (0.66–2.15) | 0.56 |
Anastomotic leak, n (%) | 118 (34) | 25 (40) | 93 (33) | 1.31 | (0.74–2.29) | 0.34 |
Bowel perforation, n (%) | 119 (35) | 16 (25) | 103 (37) | 0.57 | (0.30–1.05) | 0.07 |
Abscesses, n (%) | 61 (18) | 15 (23) | 46 (16) | 1.55 | (0.80–2.99) | 0.19 |
No demonstrated cause, n (%) | 49 (14) | 11 (17) | 38 (14) | 1.31 | (0.63–2.74) | 0.46 |
Microbiological results
Microbiological results | Bacteraemic patients (n = 64) | Patients without bacteraemia (n = 279) | |
---|---|---|---|
Blood cultures | Surgical samples | Surgical samples | |
Total number of microorganisms | 75 | 215 | 807 |
Gram-negative aerobic bacteria, n (%) | 32 (43) | 97 (45) | 312 (39) |
Enterobacteriaceae, n (%) | 27 (36) | 86 (40) | 254 (31) |
Escherichia coli, n (%) | 13 (17) | 42 (20) | 124 (15) |
Klebsiella spp., n (%) | 3 (4) | 10 (5) | 34 (4) |
Enterobacter spp., n (%) | 8 (11) | 17 (8) | 44 (5) |
Other Enterobacteriaceae, n (%) | 3 (4) | 17 (8) | 52 (6) |
Non-fermenting Gram-negative bacteria, n (%) | 4 () | 10 (5) | 44 (5) |
Pseudomonas aeruginosa, n (%) | 3 (4) | 9 (4) | 39 (5) |
Miscellaneous Gram-negative bacilli, n (%) | 1 (1) | 1 (0.5) | 14 (2) |
Gram-positive aerobic bacteria, n (%) | 22 (29) | 73 (34) | 308 (38) |
Staphylococcus aureus, n (%) | 5 (7) | 4 (2) | 26 (3) |
Coagulase-negative staphylococci, n (%) | 5 (7) | 8 (4) | 50 (6) |
Streptococcus spp., n (%) | 8 (11) | 21 (10) | 75 (9) |
Enterococcus spp., n (%) | 3 (4) | 38 (18) | 151 (19) |
Miscellaneous Gram-positive cocci, n (%) | 1 (1) | 2 (1) | 6 (1) |
Anaerobic bacteria, n (%) | 14 (19) | 22 (10) | 76 (9) |
Bacteroides spp., n (%) | 12 (16) | 18 (8) | 46 (6) |
Other anaerobes, n (%) | 2 (3) | 4 (2) | 30 (4) |
Multidrug-resistant bacteria, n (%) | 14 (19) | 26 (12) | 113 (14) |
Fungi, n (%) | 7 (9) | 23 (11) | 110 (14) |
Candida albicans, n (%) | 3 (4) | 13 (6) | 71 (9) |
Non-albicans Candida spp., n (%) | 3 (4) | 9 (4) | 32 (4) |
Risk factors for bacteraemia
Univariate analysis | Multivariable analysis | |||||
---|---|---|---|---|---|---|
Variables | Odds ratio | 95% CI | p value | Adjusted odds ratio | 95% CI | p value |
Demographic characteristics and underlying diseases | ||||||
Fatal underlying disease | 2.02 | (1.16–3.53) | 0.012 | |||
Cancer or immunosuppression | 2.64 | (1.51–4.62) | < 0.001 | 2.59 | (1.46–4.59) | 0.001 |
Severity criteria at the time of reoperation | ||||||
SOFA scorea | 1.10 | (0.59–1.75) | 0.034 | 1.19a | (1.02–1.39) | 0.002 |
Source of postoperative peritonitis and surgical observations | ||||||
Generalised peritonitis | 1.69 | (0.92–3.09) | 0.08 | |||
Interval between initial surgery and reoperationa | 1.02 | 0.98–1.05 | 0.247 | |||
Microbiological results of peritoneal surgical samples | ||||||
Enterobacteriaceaeb | 2.52 | (1.23–5.20) | 0.010 | |||
Escherichia colib | 2.13 | (1.22–3.71) | 0.008 | 2.10 | (1.19–3.73) | 0.011 |
Anti-infective therapy
Anti-infective regimens | Bacteraemic patients (n = 64) | Patients without bacteraemia (n = 279) | p value |
---|---|---|---|
Empirical therapy | |||
Combination of EAT, n (%) | 49 (77) | 226 (81) | 0.42 |
Imipenem/cilastatin, n (%) | 22 (34) | 69 (25) | 0.12 |
Piperacillin tazobactam, n (%) | 36 (56) | 173 (62) | 0.39 |
Vancomycin, n (%) | 30 (47) | 122 (44) | 0.65 |
Aminoglycosides, n (%) | 31 (48) | 140 (50) | 0.80 |
Antifungals, n (%) | 21 (33) | 101 (36) | 0.61 |
Fluconazole, n (%) | 17 (27) | 89 (32) | 0.45 |
Caspofungin, n (%) | 3 (5) | 8 (3) | 0.43 |
Adequacy of EAT, n (%) | 43 (67) | 190 (68) | 0.89 |
Documented therapy | |||
Antibiotic treatment de-escalation, n (%) | 37 (58) | 163 (58) | 0.93 |
Antibiotic treatment escalation, n (%) | 15 (23) | 72 (26) | 0.69 |
Combination of EAT, n (%) | 38 (59) | 190 (68) | 0.19 |
Imipenem/cilastatin, n (%) | 23 (36) | 56 (20) | 0.007 |
Piperacillin tazobactam, n (%) | 20 (31) | 98 (35) | 0.55 |
Vancomycin, n (%) | 16 (25) | 90 (32) | 0.25 |
Aminoglycosides, n (%) | 12 (19) | 36 (13) | 0.22 |
Antifungals, n (%) | 20 (31) | 117 (42) | 0.11 |
Fluconazole, n (%) | 16 (25) | 104 (37) | 0.06 |
Caspofungin, n (%) | 2 (3) | 7 (3) | 0.78 |
Duration of antibiotic therapy in daysa, median (IQR) | 10 (8–14) | 10 (8–14) | 0.89 |
Patient outcome and risk factors of death
Clinical outcomes | Bacteraemic patients (n = 64) | Patients without bacteraemia (n = 279) | Odds ratio | 95% CI | p value |
---|---|---|---|---|---|
On day 3 after surgery for PIAI | |||||
Temperature ≥ 36 °C and ≤ 38 °C, n (%) | 25/55 (45.4) | 165/243 (67.9) | 0.39 | (0.21–0.71) | < 0.01 |
WBC count ≥ 5000 and ≤ 15,000/mm3, n (%) | 20/55 (57.1) | 108/243 (44.4) | 0.71 | (0.39–1.31) | 0.27 |
SOFA score ≤ 3 points, n (%) | 22/55 (40) | 104/243 (42.8) | 0.89 | (0.49–1.62) | 0.70 |
All three criteria, n (%) | 7/55 (12.7) | 42/243 (17.3) | 0.69 | (0.29–1.64) | 0.54 |
Delta SOFA between day 3 and day 0, median (IQR) | 1 (0–4) | 2 (0–4) | 1.00a | (0.91–1.11) | 0.82 |
On day 7 after surgery for PIAI | |||||
Temperature ≥ 36 °C and ≤ 38 °C, n (%) | 29/44 (65.9) | 140/200 (70) | 0.82 | (0.41–1.65) | 0.59 |
WBC count ≥ 5000 and ≤ 15,000/mm3, n (%) | 23/44 (52.3) | 84/200 (42) | 1.51 | (0.78–2.91) | 0.21 |
SOFA score ≤ 3 points, n (%) | 22/44 (50) | 112/200 (56) | 0.78 | (0.41–1.51) | 0.46 |
All three criteria, n (%) | 12/44 (27.3) | 44/200 (22) | 1.33 | (0.63–2.79) | 0.45 |
Delta SOFA between day 7 and day 0, median (IQR) | 3.5 (1.2–6) | 4 (1–6) | 0.98a | (0.89–1.11) | 0.93 |
Suspected persistent sepsis, n (%) | 36 (58) | 144 (53) | 1.21 | (0.69–2.11) | 0.50 |
Reoperation, n (%) | 29 (45) | 122 (44) | 1.02 | (0.59–1.76) | 0.81 |
Total number of reoperations, median (IQR) | 1 (1–2) | 2 (1–2) | 0.88 | (0.71–1.10) | 0.21 |
Interval between surgery for PIAI and reoperation, median (IQR) | 5 (2.5–7) | 5 (2–8) | 0.97 | (0.87–1.08) | 0.42 |
Main reasons for reoperation | |||||
Septic shock/multiple organ failure, n (%) | 11/29 (38) | 47/122 (39) | 0.97 | (0.42–2.24) | 0.95 |
Sepsis, n (%) | 18/29 (62) | 75/122 (62) | 1.02 | (0.44–2.36) | 0.95 |
Haemorrhage, n (%) | 2/29 (7) | 9/122 (7) | 0.93 | (0.18–4.55) | 1 |
Suspicion of bowel ischaemia, n (%) | 2/29 (7) | 26/122 (21) | 0.27 | (0.06–1.22) | 0.11 |
Main intraoperative diagnoses at reoperation | |||||
Anastomotic leak, n (%) | 8/29 (28) | 29/122 (24) | 1.22 | (0.48–3.04) | 0.64 |
Bowel perforation, n (%) | 4/29 (14) | 25/122 (20) | 0.62 | (0.19–1.94) | 0.60 |
Ischaemia, n (%) | 2/29 (7) | 23/122 (19) | 0.31 | (0.07–1.43) | 0.17 |
Abscess or collections, n (%) | 5/29 (17) | 14/122 (11) | 1.60 | (0.53–4.89) | 0.37 |
No identified cause, n (%) | 5/29 (17) | 10/122 (8) | 2.33 | (0.73–7.44) | 0.16 |
Medical complications, n (%) | 5 (8) | 37 (14) | 0.55 | (0.20–1.47) | 0.29 |
Duration of mechanical ventilation, median (IQR), daysb | 8 (4–15) | 7 (3–15) | 1.45 | (0.71–2.95) | 0.75 |
ICU stay, median (IQR), daysb | 12 (8–23) | 15 (8–25) | 0.96 | (0.48–1.94) | 0.39 |
Death in ICU, n (%) | 26 (41) | 82 (29) | 1.64 | (0.94–2.88) | 0.08 |
Death in hospital, n (%) | 26 (41) | 88 (32) | 1.48 | (0.85–2.59) | 0.16 |
Univariate analysis | Multivariate analysis | |||||
---|---|---|---|---|---|---|
Parameters | Odds ratio | 95% CI | p value | Odds ratio | 95% CI | p value |
Demographic characteristics and underlying diseases | ||||||
Age > 62 years | 2.45 | (1.55–3.90) | < 0.001 | |||
McCabe Fatal | 1.55 | (0.96–2.49) | 0.08 | |||
Immunosuppression or cancer | 1.83 | (1.15–2.92) | 0.01 | |||
Urgent initial surgery | 2.04 | (1.29–3.23) | 0.002 | 2.71 | (1.53–4.81) | 0.0006 |
Severity criteria at the time of reoperation | ||||||
Small bowel perforation | 1.57 | (0.95–2.59) | 0.07 | |||
SAPS II > 47 at reoperation | 4.26 | (2.61–6.94) | < 0.001 | 4.78 | (2.71–8.45) | < 0.0001 |
Blood and peritoneal microbiological results | ||||||
Bacteraemia | 1.48 | (0.84–2.59) | 0.16 | 1.62 | (0.81–3.24) | 0.169 |
Peritoneal samples involving | ||||||
Enterococci | 1.71 | (1.08–2.69) | 0.019 | |||
Non-fermenting Gram-negative Bacteria | 2.01 | (1.13–3.65) | 0.019 | |||
Streptococci | 0.54 | (0.30–0.96) | 0.037 | |||
Empirical and documented therapies | ||||||
Empirical imipenem therapy | 1.66 | (1.01–2.72) | 0.044 | |||
Empirical vancomycin therapy | 1.56 | (0.99–2.46) | 0.050 | |||
Empirical antifungal therapy | 1.72 | (1.08–2.74) | 0.019 | 2.91 | (1.62–5.22) | 0.0003 |
De-escalation documented therapy | 0.54 | (0.34–0.85) | 0.007 | 0.50 | (0.28–0.89) | 0.018 |
Documented therapy using piperacillin/tazobactam | 1.74 | (1.09–2.78) | 0.018 | |||
Documented antifungal therapy | 1.67 | (1.05–2.63) | 0.026 |