Outcomes by system
| Non-ETS (n) | ETS (n) | RR (95% CI) | |||
| Yes | No | Yes | No | ||
| Outcomes of respiratory system | |||||
| Meconium aspiration syndrome | |||||
| Chettri et al, 201531 | 19 | 42 | 20 | 41 | 0.95 (0.57 to 1.59) |
| Nangia et al, 201632 | 23 | 65 | 28 | 59 | 0.81 (0.51 to 1.29) |
| Kumar et al, 201933 | 15 | 51 | 21 | 45 | 0.71 (0.40 to 1.26) |
| Singh et al, 201934 | 44 | 33 | 31 | 44 | 1.38 (0.99 to 1.93) |
| Subtotal (I2=48.5%, p=0.12) | 0.98 (0.71 to 1.35) | ||||
| Total events/total infants (%) | 101/292 (35) | 100/289 (35) | 201/581 (35) | ||
| Pneumothorax | |||||
| Chettri et al 201531 | 1 | 60 | 1 | 60 | 1.00 (0.06 to 15.63) |
| Nangia et al 201632 | 2 | 86 | 2 | 85 | 0.99 (0.14 to 6.86) |
| Singh et al 201934 | 2 | 75 | 3 | 72 | 0.65 (0.11 to 3.78) |
| Subtotal (I2=0.0%, p=0.94) | 0.82 (0.25 to 2.66) | ||||
| Total events/total infants (%) | 5/226 (2) | 6/223 (3) | 11/449 (2) | ||
| Persistent pulmonary hypertension of the newborn | |||||
| Chettri et al 201531 | 2 | 59 | 4 | 57 | 0.50 (0.10 to 2.63) |
| Kumar et al 201933 | 2 | 64 | 4 | 62 | 0.50 (0.09 to 2.64) |
| Singh et al 201934 | 7 | 70 | 6 | 69 | 1.14 (0.40 to 3.22) |
| Subtotal (I2=0.0%, p=0.59) | 0.79 (0.36 to 1.73) | ||||
| Total events/total infants (%) | 11/204 (5) | 14/202 (7) | 25/406 (6) | ||
| Secondary pneumonia | |||||
| Chettri et al 201531 | 8 | 53 | 6 | 55 | 1.33 (0.49 to 3.61) |
| Singh et al 201934 | 19 | 58 | 17 | 58 | 1.09 (0.61 to 1.93) |
| Subtotal (I2=0.0%, p=0.73) | 1.14 (0.70 to 1.88) | ||||
| Total events/total infants (%) | 27/138 (20) | 23/136 (17) | 50/274 (18) | ||
| Need for respiratory support, including mechanical ventilation | |||||
| Nangia et al, 201632 | 15 | 73 | 17 | 70 | 0.87 (0.47 to 1.63) |
| Kumar et al, 201933 | 47 | 19 | 48 | 18 | 0.98 (0.79 to 1.21) |
| Singh et al, 201934 | 69 | 8 | 65 | 10 | 1.03 (0.92 to 1.16) |
| Subtotal (I2=0.0%, p=0.73) | 1.02 (0.92 to 1.13) | ||||
| Total events/total infants (%) | 131/231 (57) | 130/228 (57) | 261/459 (57) | ||
| Need for mechanical ventilation | |||||
| Chettri et al, 201531 | 15 | 46 | 14 | 47 | 1.07 (0.57 to 2.02) |
| Nangia et al, 201632 | 8 | 80 | 11 | 76 | 0.72 (0.30 to 1.70) |
| Kumar et al, 201933 | 8 | 58 | 9 | 57 | 0.89 (0.37 to 2.16) |
| Singh et al, 201934 | 13 | 64 | 11 | 64 | 1.15 (0.55 to 2.41) |
| Subtotal (I2=0.0%, p=0.85) | 0.98 (0.67 to 1.43) | ||||
| Total events/total infants (%) | 44/292 (15) | 45/289 (16) | 89/581 (15) | ||
| Outcomes of cardiovascular system, neurological system, neonatal mortality and infection | |||||
| Outcomes of cardiovascular system | |||||
| Shock | |||||
| Chettri et al, 201531 | 15 | 46 | 12 | 49 | 1.25 (0.64 to 2.45) |
| Kumar et al, 201933 | 4 | 62 | 9 | 57 | 0.44 (0.14 to 1.37) |
| Subtotal (I2=58.7%, p=0.12) | 0.83 (0.30 to 2.24) | ||||
| Total events/total infants (%) | 19/127 (15) | 21/127 (17) | 40/254 (16) | ||
| Outcomes of nervous system | |||||
| Perinatal asphyxia/hypoxic-ischaemic encephalopathy | |||||
| Chettri et al, 201531 | 17 | 44 | 19 | 42 | 0.89 (0.52 to 1.55) |
| Nangia et al, 201632 | 27 | 61 | 28 | 59 | 0.95 (0.62 to 1.48) |
| Kumar et al, 201933 | 10 | 56 | 8 | 58 | 1.25 (0.53 to 2.97) |
| Singh et al, 201934 | 30 | 47 | 20 | 55 | 1.46 (0.91 to 2.33) |
| Subtotal (I2=0.0%, p=0.48) | 1.10 (0.85 to 1.43) | ||||
| Total events/total infants (%) | 84/292 (29) | 75/289 (26) | 159/581 (27) | ||
| Convulsions | |||||
| Chettri et al, 201531 | 23 | 38 | 23 | 38 | 1.00 (0.63 to 1.58) |
| Kumar et al, 201933 | 5 | 61 | 6 | 60 | 0.83 (0.27 to 2.60) |
| Subtotal (I2=0.0%, p=0.77) | 0.98 (0.64 to 1.49) | ||||
| Total events/total infants (%) | 28/127 (22) | 29/127 (23) | 57/254 (22) | ||
| Neonatal mortality | |||||
| Chettri et al, 201531 (in 7 days) | 8 | 53 | 7 | 54 | 1.14 (0.44 to 2.96) |
| Nangia et al, 201632 | 4 | 84 | 9 | 78 | 0.44 (0.14 to 1.37) |
| Kumar et al, 201933 | 5 | 61 | 9 | 57 | 0.56 (0.20 to 1.57) |
| Singh et al, 201934 | 7 | 70 | 4 | 71 | 1.70 (0.52 to 5.58) |
| Subtotal (I2=17.1%, p=0.31) | 0.83 (0.46,1.49) | ||||
| Total events/total infants (%) | 24/292 (8) | 29/289 (10) | 53/581(9) | ||
| Outcomes of infection | |||||
| Blood culture-positive sepsis | |||||
| Chettri et al, 201531 | 5 | 56 | 3 | 58 | 1.67 (0.42 to 6.67) |
| Kumar et al, 201933 | 0 | 66 | 2 | 64 | 0.20 (0.01 to 4.09) |
| Singh et al, 201934 | 1 | 76 | 3 | 72 | 0.32 (0.03 to 3.05) |
| Subtotal (I2=21.2%, p=0.28) | 0.74 (0.20 to 2.76) | ||||
| Total events/total infants (%) | 6/204 (3) | 8/202 (4) | 14/406 (3) | ||
| Outcomes regarding the need for initial resuscitation | |||||
| Positive pressure ventilation | |||||
| Chettri et al, 201531 | 55 | 6 | 53 | 8 | 1.04 (0.91 to 1.18) |
| Nangia et al, 201632 | 79 | 9 | 68 | 19 | 1.15 (1.01 to 1.31) |
| Kumar et al, 201933 | 37 | 29 | 41 | 25 | 0.90 (0.68 to 1.20) |
| Singh et al, 201934 | 56 | 21 | 53 | 22 | 1.03 (0.84 to 1.26) |
| Subtotal (I2=1.1%, p=0.39) | 1.06 (0.98 to 1.15) | ||||
| Total events/total infants (%) | 227/292 (78) | 215/289 (74) | 442/581 (76) | ||
| Positive pressure ventilation via ET tube | |||||
| Chettri et al, 201531 | 27 | 34 | 31 | 30 | 0.87 (0.60 to 1.27) |
| Nangia et al, 201632 | 14 | 74 | 16 | 71 | 0.87 (0.45 to 1.66) |
| Kumar et al, 201933 | 25 | 41 | 31 | 35 | 0.81 (0.54 to 1.20) |
| Singh et al, 201934 | 23 | 54 | 20 | 55 | 1.12 (0.67 to 1.86) |
| Subtotal (I2=0.0%, p=0.79) | 0.89 (0.71 to 1.12) | ||||
| Total events/total infants (%) | 89/292 (30) | 98/289 (34) | 187/581 (32) | ||
| Chest compression | |||||
| Chettri et al, 201531 | 1 | 60 | 3 | 58 | 0.33 (0.04 to 3.12) |
| Nangia et al, 201632 | 2 | 86 | 1 | 86 | 1.98 (0.18 to 21.41) |
| Kumar et al, 201933 | 5 | 61 | 3 | 63 | 1.67 (0.42 to 6.69) |
| Singh et al, 201934 | 4 | 73 | 4 | 71 | 0.97 (0.25 to 3.75) |
| Subtotal (I2=0.0%, p=0.64) | 1.11 (0.48 to 2.55) | ||||
| Total events/total infants (%) | 12/292 (4) | 11/289 (4) | 23/581 (4) | ||
| Epinephrine | |||||
| Chettri et al, 201531 | 1 | 60 | 3 | 58 | 0.33 (0.04 to 3.12) |
| Nangia et al, 201632 | 1 | 87 | 1 | 86 | 0.99 (0.06 to 15.56) |
| Kumar et al, 201933 | 2 | 64 | 1 | 65 | 2.0 (0.19 to 21.53) |
| Singh et al, 201934 | 1 | 76 | 1 | 74 | 0.97 (0.06 to 15.29) |
| Subtotal (I2=0.0%, p=0.75) | 0.85 (0.24 to 2.97) | ||||
| Total events/total infants (%) | 5/292 (2) | 6/289 (2) | 11/581 (2) | ||
| Duration of mechanical ventilation and hospital stay* | |||||
| Duration of mechanical ventilation (h) | Mean difference (95% CI) | ||||
| Nangia et al, 201632 | 31.5±10.50 | 30±10.00 | 1.50 (–1.54 to 4.54) | ||
| Kumar et al, 201933 | 24±40.74 | 34±34.07 | –10.00 (–22.81 to 2.81) | ||
| Singh et al, 201934 | 83.04±15.84 | 78.48±26.40 | 4.56 (–2.38 to 11.50) | ||
| Subtotal (I2=47.9%, p=0.15) | 0.90 (–4.37 to 6.17) | ||||
| Duration of hospital stay (d) | Mean difference (95% CI) | ||||
| Nangia et al, 201632 | 2.95±0.86 | 2.99±1.26 | –0.04 (–0.36 to 0.28) | ||
| Kumar et al, 201933 | 1.83±2.35 | 2.25±3.40 | –0.42 (–1.42 to 0.58) | ||
| Singh et al, 201934 | 11.17±3.73 | 9.91±3.06 | 1.26 (0.18 to 2.34) | ||
| Subtotal (I2=66.2%, p=0.05) | 0.19 (–0.59 to 0.97) | ||||
RR >1 indicated that the risk of acquiring illness or disease was greater in the non-ETS group and RR <1 indicated that the risk of acquiring illness or disease was lower in the non-ETS group
*The data were converted from median and range or IQR to mean and SD.
CI, confidence interval; ETS, endotracheal suctioning; RR, relative risk.