. 2015 Mar 26;10(3):e0119469. doi: 10.1371/journal.pone.0119469

Table 1. Study characteristics. Values are numbers, mean ± SD, or median (range) or absolute number.

First author, year, reference	Group	N	Age	Weight	OLP^* measurement method	Type of surgery	Use of NMBD^†
Gasteiger, 2010 [13]	i-gel	76	40 ± 13	65 ± 11	manometric	elective gynaecological or orthopaedic surgery in supine position	No
Gasteiger, 2010 [13]	PLMA^‡	76	41 ± 12	65 ± 11	manometric		No
Van Zundert, 2012 [15]	i-gel	50	41 ± 14	71 ± 14	manometric	elective peripheral or superficial surgery in supine position (≥30 min)	No
	PLMA	50	43 ± 15	73 ± 13
	SLMA	50	41 ± 15	74 ± 14
Sharma, 2010 [10]	i-gel	30	42.10 ± 11.40	57.1 ± 8.48	audible	elective laparoscopic cholecystectomy	Yes
Sharma, 2010 [10]	PLMA	30	35.43 ± 11.10	58.15 ± 11.25	audible	elective laparoscopic cholecystectomy	Yes
Chauhan, 2013 [12]	i-gel	40	32.13 ± 11.69	57.1±8.48	audible	elective surgery in the supine position	Yes
Chauhan, 2013 [12]	PLMA	40	32.43 ± 7.27	58.15 ± 11.25	audible	elective surgery in the supine position	Yes
Singh, 2009 [4]	i-gel	30	38.31 ± 12.24	60.24 ± 10.89	audible	elective hernioplasty, laparoscopic cholecystectomy, tibial plating, humerus plating, skin grafting	Yes
Singh, 2009 [4]	PLMA	30	39.86 ± 13.08	61.27 ± 11.85	audible		Yes
Jeon, 2012 [14]	i-gel	15	43 (36.5–44.0)	59.2 ± 4.4	manometric	laparoscopic gynecological operation	Yes
Jeon, 2012 [14]	PLMA	15	45 (39.7–47.8)	62.4 ± 6.6	manometric	laparoscopic gynecological operation	Yes
Shin, 2010 [11]	i-gel	64	42 ± 16	64 ± 17	manometric	lower-extremity orthopaedic surgery	Yes
	PLMA	53	44 ± 15	66 ± 12
	CLMA^§	50	48±13	64 ± 12
Hayashi, 2013 [21]	i-gel	50	55.4 ± 18.6	61.2 ± 11.9	manometric	elective surgery in supine position	No
Hayashi, 2013 [21]	PLMA	50	60.0 ± 16.8	58.4 ± 10.3	manometric	elective surgery in supine position	No
Trivedi, 2011 [2]	i-gel	30	28.13 ± 10.01	47.9 ± 7.67	not reported	surgery under general anesthesia (≤2hours)	Yes
Trivedi, 2011 [2]	PLMA	30	31.16 ± 11.16	51.4 ± 6.07	not reported	surgery under general anesthesia (≤2hours)	Yes
Shi, 2013 [20]	i-gel	30	45 ± 11	62 ± 10	not reported	laparoscopic gynecological surgery	Yes
Shi, 2013 [20]	PLMA	30	40 ± 10	61 ± 8	not reported	laparoscopic gynecological surgery	Yes
Kini, 2014 [22]	i-gel	24	36.58±10.12	23.07±3.11 (BMI)	audible	elective short procedures requiring general anesthesia	No
Kini, 2014 [22]	PLMA	24	33.63±10.60	22.35±3.33 (BMI)	audible	elective short procedures requiring general anesthesia	No
Das, 2014 [23]	i-gel	30	23.6±3	50.33±3.09	not reported	elective sugeries for < 1 hour duration in supine position	Yes
Das, 2014 [23]	PLMA	30	22.57±2.64	50.37±2.74	not reported	elective sugeries for < 1 hour duration in supine position	Yes

* OLP: oropharyngeal leak pressure;

†NMBD: neuromuscular blocking drug;

‡PLMA: proseal LMA;

§CLMA: classic LMA.