| Outcomes | Results |
| Primary Outcomes | |
| Ventilator‐associated pneumonia | Adams 1997
VAP (NS): 0/10 CTSS, 0/10 OTSS.
Combes 2000
1. VAP (NS):
CTSS: 7.4% (4/54) representing 7.32 VAP per 1000 patient days.
OTSS: 18% (9/50) representing 15.98 VAP per 1000 patient days.
OTSS was accompanied by a 3.5 fold higher risk of VAP; prophylactic use of gastric acid secretion inhibitors increased this risk 4.3 times (P 0.04).
2. Time to the VAP occurrence (NS): 5 (3‐10) days CTSS, 5 (2‐23) days OTSS.
Conrad 1989
Nosocomial pneumonia (NS): 38% (6/16) CTSS, 35.3% (6/17) OTSS.
Time to infection (NS): 5.8 ± 2.6 days CTSS, 4.1 ± 0.9 days OTSS.
Infection rate (NS): 0.04 per day CTSS, 0.054 per day OTSS.
Deppe 1990
Nosocomial pneumonia incidence (NS): 26% (12/46) CTSS, 29% (11/38) OTSS.
When evaluating 1) hospitalization <72h prior to entering the study (N: 52) and 2) hospitalization >72h prior to entering the study (N: 32) there was no statistical difference between CTSS and OTSS.
Johnson 1994
Nosocomial pneumonia (NS): 50% (8/16) CTSS vs. 52.6% (10/19) OTSS.
Lorente 2005
1. VAP (NS): 20.47% (43/210) CTSS, 18.02% (42/233) OTSS.
2. Cases of VAP per 1000 days of mechanical ventilation (NS): 17.59% (46/2615) CTSS, 15.84% (47/2966) OTSS.
Lorente 2006
1. VAP
CTSS= 13.9% (33/236)
OTSS = 14.1% (31/221) (P=0.99)
2. Cases of ventilator associated pneumonia per 1000 days of mechanical ventilation
CTSS = 14.1% (33/2336)
OTSS = 14.6% (31/2113) (P=0.8)
Rabitsch 2004
VAP: 0% (0/12) CTSS, 41.67% (5/12) OTSS (P=0.037)
Topeli 2004
1. VAP (NS): 31.7% (13/41) CTSS, 24.3% (9/37) OTSS.
2. Time from intubation to the development of VAP (NS): 8.1±1 days CTSS, 7.7±2.3 days OTSS.
Welte 1997
VAP (signification not stated): 33.3% (9/27) CTSS, 64% (16/25) OTSS.
Zeitoun 2003
VAP (NS): 30.4% (7/23) CTSS, 45.8% (11/24) OTSS. |
| Mortality | Combes 2000
Mortality (NS): 26% (14/54) CTSS, 28% (14/50) OTSS.
Deppe 1990
Mortality (NS): 26% (12/46) CTSS, 29% (11/38) OTSS.
Lorente 2005
Mortality (NS): 24.7% (52/210) CTSS, 21.4% (50/233) OTSS.
Lorente 2006
Mortality
CTSS = 13.1% (31/236)
OTSS = 13.5% (30/221) (P=0.78)
Topeli 2004
3. Mortality in ICU (NS): 65.9% (27/41) CTSS, 67.6% (25/37) OTSS.
Surrogate outcome: Time on ventilation
Conrad 1989
Time on ventilator (NS): 12.4 (15.2) days CTSS, 7.6 (5.2) days OTSS.
Lorente 2005
Days on mechanical ventilation (NS): 12.45±14.07 CTSS, 12.72±14.14 OTSS.
Lorente 2006
Days on mechanical ventilation
CTSS =9.9±12.1
OTSS =9.5±12.1 (P=0.76)
Topeli 2004
Duration of MV (NS): 8.2±0.7 days CTSS, 7.5±1.0 days OTSS. |
| Secondary Outcomes | |
| Bacterial Colonization | Adams 1997
Microbiological analysis of endotracheal aspirate (NS):
Patients with microorganism isolated for CTSS at 24 hours: 3/10; at day 2‐3: 3/6; at day 4‐5: 0/0; at day 6‐7: 0/0.
Patients with microorganism isolated for OTSS at 24 hours: 3/10; at day 2‐3: 2/3; at day 4‐5: 1/2; at day 6‐7: 1/1.
Deppe 1990
Colonization rates (P<0.02): 67% (31/46) CTSS, 39% (15/38) OTSS.
Gallagher 1994
1. Colonization incidence with acinetobacter calcoaceticus (NS): 13/99 CTSS, 7/99 OTSS.
2. Time to colonization (NS): 53.5 (15.5‐313.0) CTSS, 132.0 (28.5‐368.5) OTSS.
Topeli 2004
Colonization rate (NS): 16/41 CTSS, 13/37 OTSS.
Welte 1997
Colonization (NS): 14.8% (4/27) CTSS, 8% (2/25) OTSS.
Surrogate outcome: Cross‐contamination
Rabitsch 2004
Cross‐contamination between the bronchial system and the gastric juices (P=0.037; as reported by the authors)
0% (0/12) CTSS, 41.67% (5/12) OTSS.
5. VAP (P=0.037; as reported by the authors)
0% (0/12) CTSS, 41.67% (5/12) OTSS. |
| Length of stay in the ICU | Combes 2000
Length of stay (NS): 15.6 ± 13.4 days CTSS, 19.9 ± 16.7 days OTSS.
Topeli 2004
Length of ICU stay (NS): 12.3±7.04 days CTSS, 11.5±8.54 days OTSS. |
| Respiratory outcomes | Cereda 2001
1. Drop in lung volume (P<0.05): ‐133.5 ± 129.9 CTSS, ‐1231.5 ± 858.3 OTSS.
2. SpO2 (P<0.05): 97.2 ± 2.9 CTSS, 94.6 ± 5.1 OTSS.
3. PaO2 (NS): before suctioning with CTSS (123.5±26.1) and after suctioning with CTSS (123.2±25.7). Before suctioning with OTSS (122.6±26.0) and after suctioning with OTSS (117.3±31.1).
4. PaCO2 (NS): before suctioning with CTSS (48.1±14.3) and after suctioning with CTSS (47.9±14). Before suctioning with OTSS (47.4±14.0) and after suctioning with OTSS (49.2±14.3).
5. PaO2 (NS): before suctioning with CTSS (123.5±26.1) and after suctioning with CTSS (123.2±25.7). Before suctioning with OTSS (122.6±26.0) and after suctioning with OTSS (117.3±31.1).
6. HbO2 (NS): before suctioning with CTSS (95.6±2.6) and after suctioning with CTSS (95.7±2.6). Before suctioning with OTSS (96.6±2.7) and after suctioning with OTSS (95.2±3.3).
7. Respiratory rate (P<0.05): before suctioning with CTSS (15.1±4.5), during suction (39.8±6.6) and after suctioning with CTSS (15.1±5.4). Before suctioning with OTSS (15.1±4.3) and after suctioning with OTSS (15.1±4.3).
8. Airway pressure (P<0.05): before suctioning with CTSS (15.9±5.1), during suction (18.0±5.5) and after suctioning with CTSS (15.9±5.1). Before suctioning with OTSS (16±5.1) and after suctioning with OTSS (15.9±5.1).
Johnson 1994
1. Mean arterial pressure
Change from B to AH (P=0.0019): +0.7% (89±1.3mmHg) CTSS vs. +4% (92±1.7 mmHg) OTSS.
Change from B to AS (P=0.0001): +8.6% (97±1.4 mmHg) CTSS vs. +17.3% (102±1.7 mmHg) OTSS.
Change from B to 30s (P=0.0001): +7.9% (101±1.6 mmHg) CTSS vs. +15.2% (96±1.2 mmHg) OTSS.
2. Oxygen saturation
Change from B to AH (P=0.0005): +0.3% (98±0.2%) CTSS vs. ‐0.4% (97±0.3%) OTSS.
Change from B to AS (P=0.0001): +1.6% (99±0.1%) CTSS vs. ‐1.1% (99±0.1%) OTSS.
Change from B to 30s (P=0.0001): +1.4% (99±0.1%) CTSS vs. ‐0.4% (97±0.1%) OTSS.
3. Systemic venous oxygen saturation
Change from B to AH (NS): +0.3% (73±0.9%) CTSS vs. ‐0.9% (72±0.9%) OTSS.
Change from B to AS (P=0.0001): +2.1% (74±0.9%) CTSS vs. ‐8.3% (67±1.5%) OTSS.
Change from B to 30s (P=0.0001): +3.4% (75±1.0%) CTSS vs. ‐7.7% (67±1.4%) OTSS.
Lee 2001
1. Oxygen saturation (NS at BL1, T2 and T5. Significant at S1, S2 and BL2)
Values at BL1 (NS): 96.36±3.27% CTSS vs 95.50±4.70% OTSS.
Values at T2 (NS): 95.79±3.87% CTSS vs 94.86±5.99% OTSS.
Values at T5 (NS): 95.5±3.74% CTSS vs 94.93±5.34% OTSS.
Values at S1 (P<0.05): 98.29±2.40% CTSS vs 97±4.66% OTSS (CTSS BL1 vs CTSS S1; OTSS BL1 vs OTSS S1).
Values at BL2 (P<0.05): 98.07±2.87% CTSS vs 95.36±5.9% OTSS (CTSS BL1 vs CTSS BL2; CTSS vs OTSS).
Values at S2 (P<0.05): 97±3.64% CTSS vs 95.79±5.67% OTSS (CTSS vs OTSS).
2. Mean arterial pressure (NS at BL1, T2 and T5. Significant at S1, S2 and BL2)
Values at BL1 (NS): 87.57±18.03 mmHg CTSS vs 89.43±19.54 mmHg OTSS.
Values at T2 (NS): 91.29±19.35 mmHg CTSS vs 89.43±18.59 mmHg OTSS.
Values at T5 (NS): 86.86±17.68 mmHg CTSS vs 85.36±16.75 mmHg OTSS.
Values at S1 (P<0.05): 91.21±18.58 mmHg CTSS vs 92.79±17.98 mmHg OTSS (CTSSBL1 vs. CTSSS1).
Values at BL2 (P<0.05): 84.64±19.68 mmHg CTSS vs 93.14±21.03 mmHg OTSS (OTSSBL1 vs OTSSBL2; CTSS vs OTSS).
Values at S2 (P<0.05): 92.36±21.44 mmHg CTSS vs 95.71±21.73 mmHg OTSS. (CTSSBL1 vs CTSSS2; OTSSBL1 vs OTSSS2)
3. Respiratory rate (NS at BL1, S1, BL2, S2, T2 and T5)
Values at BL1 (NS): 21.43±7.61 breaths/min CTSS vs 20.21±6.44 breaths/min OTSS.
Values at S1 (NS): 20.14±6.63 breaths/min CTSS vs 22±9.98 breaths/min OTSS.
Values at BL2 (NS): 20.43±7.45 breaths/min CTSS vs 23.21±10.23 breaths/min OTSS:
Values at S2 (NS): 22.43±7.39 breaths/min CTSS vs 23.29±10.62 breaths/min OTSS.
Values at T2 (NS): 23.14±8.5 breaths/min CTSS vs 22.14±8.58 breaths/min OTSS.
Values at T5 (NS): 23.43±7.95 breaths/min CTSS vs 21.07±7.49 breaths/min OTSS.
Rabitsch 2004
Oxygen saturation:
SaO2 at beginning of suctioning day1: 96.3±1.4% CTSS, 97.2±1.9% OTSS.
SaO2 at the end of suctioning day1: 96.8±1.0% CTSS, 89.6±2.5% CTSS.
(P<0.0001) OTSS at the beginning of suctioning vs. OTSS at the end of suctioning.
Sa O2 at beginning of suctioning day3: 97.0±1.4% CTSS, 96.8±1.0% OTSS.
Sa O2 at the end of suctioning day3: 96.4±0.8 CTSS, 89.6±1.9 CTSS.
(P<0.0001) OTSS at the beginning of suctioning vs. OTSS at the end of suctioning. |
| Cardiovascular outcomes | Cereda 2001
1. Heart rate (NS): before suctioning with CTSS (97.1±21.9), during suction (100.2±20.0) and after suctioning with CTSS (97.6±21.3). Before suctioning with OTSS (98.7±22.3) during suction (97.5±21.4) and after suctioning with OTSS (98.1±22.5).
2. Mean arterial pressure (P<0.05): before suctioning with CTSS (79.4±11.7), during suction (81.2±11.9) and after suctioning with CTSS (80.0±11.6). Before suctioning with OTSS (78.1±10.2) during suction (83.2±14.7) and after suctioning with OTSS (84.5±13.6).
Johnson 1994
1. Heart rate
Change from B to AH (NS): +1.2% (98±1.4 beats/min) CTSS vs +2.2% (108±1.8 beat/min) OTSS.
Change from B to AS (NS): +5.7% (102±1.5 beats/min) CTSS vs +8.1% (114±1.7 beat/min) OTSS.
Change from B to 30s (P=0.0209): +3.6% (100±1.4 beats/min) CTSS vs +6.4% (112±1.8 beats/min) OTSS.
2. Heart rhythm (P = 0.0001)
Dysrhythmias 2% (3/149 suctioning passes) CTSS vs 14% (8/127 suctioning passes) OTSS.
Lee 2001
1. Heart rate (NS at BL1, T2 and T5. Significant at S1, S2 and BL2)
Values at BL1 (NS): 100±19.6beats/min CTSS vs 100.29±22.05 beats/min OTSS.
Values at T2 (NS): 100.43±19.79 beats/min CTSS vs 106.86±29.87 beats/min OTSS.
Values at T5 (NS): 99.43±21.51 beats/min CTSS vs 105.07±29.65 beats/min OTSS.
Values at S1 (P<0.05): 96.43±20.4 beats/min CTSS vs 102.29±20.53 beats/min OTSS.
Values at BL2 (P<0.05): 96.14±20 beats/min CTSS vs 101±20.49 beats/min OTSS. (CTSSBL1 vs CTSSBL2)
Values at S2 (P<0.05): 97.43±19.79 beats/min CTSS vs. OTSS: 106.86±29.87 beats/min;
2. Heart rhythm (P<0.05)
Dysrhythmias 0% (0/13 suctioning manoeuvre) CTSS, 38.5% (5/13 suctioning manoeuvre) OTSS. |
| Technique related outcomes | Adams 1997
Suctions per day (NS): 16.6 (2‐33) CTSS, 10 (0‐43) OTSS
Conrad 1989
1. Suction frequency (NS): 10.6 per day CTSS, 8.8 per day OTSS.
2. Antibiotic usage (NS): 94% (15/16) CTSS, 88% (15/17) OTSS.
3. Nasogastric tube (NS): 50% (8/16) CTSS, 36% (6/17) OTSS.
Deppe 1990
Suctions per day (P<0.054): 16.6 CTSS, 12.4 OTSS. Analysis performed in 41 patients, 23 CTSS, 18 OTSS.
Lorente 2005
Aspirations per day (NS): 8.13±3.54 CTSS, 8.32±3.71 OTSS.
Lorente 2006
Aspirations per day
CTSS =8.1±2.7
OTSS =7.9±2.6 (P=0.64)
Rabitsch 2004
1. Number of suctioning per day (NS)
Day1, 7 (6‐9) and day3, 8 (6‐9) for CTSS. Day1, 8 (6‐9) and day3, 8 (6‐10) for OTSS.
2. Quantity of secretions (NS)
Day1, 2 little, 6 moderate, 4 profuse. Day3, 2 little, 6 moderate, 4 profuse for CTSS.
Day1, 2 little, 7 moderate, 3 profuse. Day3, 2 little, 6 moderate, 4 profuse for OTSS.
Witmer 1991
Quantity of secretions removed (NS): 1.7 g CTSS, 1.9 g OTSS
Zielmann 1992
Suctions performed. During the total study period a median of 15 suction manoeuvres were performed; group distribution not stated. |
| Nursing related outcomes | Johnson 1994
Nursing time (P = 0.0001): 93 seconds per procedure CTSS vs 153 seconds per procedure OTSS
Zielmann 1992
Nursing time (significance data not stated): 2.5 (2‐4) CTSS, 3.5 (2‐6) OTSS. |
| Comments | The outcomes showed significant differences, unless otherwise stated (NS)
ALI: acute lung injury; ARDS: acute respiratory distress syndrome; COPD: chronic obstructive pulmonary disease; CTSS: closed tracheal suction system; ET: endotracheal; ICU: intensive care unit; MV: mechanical ventilation; NS: non‐significant; OTSS: open tracheal suction system; PEEP: positive‐pressure respiration; RCT: randomized controlled trial; VAP: ventilator associated pneumonia
Johnson 1994: Data was collected before suctioning, baseline (B), after hyperoxygenation (AH), immediately after suctioning (AS) and 30 seconds after suctioning (30s).
Lee 2001: Data was collected before the two suction manoeuvres (BL1 and BL2), at the moment of the manoeuvres (S1 and S2), and then 2 and 5 minutes post‐suctioning (T2 and T5). |
