Can optic nerve sheath diameter assess increased intracranial pressure in pneumoperitoneum and trendelenburg position?

Figures & data

Figure 1. U/S image of ONSD measurement. It shows the U/S measurement of op in centimeters. The caliper “A” measures the depth at which the ONSD must be measured (3 mm). “B” measures the ONSD (7.2 mm) at this depth.

Table 1. Demographic characteristics of the study patients and intraoperative data.

	Mean	SD	Range
Age (years)	30.50	11.038	18–60
Height (cm)	161.85	5.081	154–174
Weight (kg)	73.45	8.709	59–93
BMI (kg\m^2)	27.99	2.67	23.44–32.41
Intraoperative fluid intake (ml)	1253.5	215.2	800–2100
Intraoperative Blood Loss (ml)	192.4	97.6	100–400
Trendelenburg time (min)	92.6	19.3	75–105
Operation time (min)	118.3	25.4	95–130

Values are presented as mean, SD and range

Table 2. Comparison between optic nerve sheath sagittal and transverse diameters in both right and left eyes at different time points.

		Sagittal ONSD	Transverse ONSD
	Time points	Mean ± SD	Mean ± SD	P-value^a
Right eye	Baseline	0.369 ± 0.044^d	0.365 ± 0.042^d	0.77 (NS)
	After induction	0.409 ± 0.069^d	0.41 ± 0.073^d	0.89 (NS)
	5 min. after insufflation	0.486 ± 0.095^b c d	0.490 ± 0.096^b c d	0.89 (NS)
	15 min. after insufflation	0.530 ± 0.099^b c	0.525 ± 0.106^b c	0.86 (NS)
	30 min. after insufflation	0.557 ± 0.102^b c	0.561 ± 0.105^b c	0.91 (NS)
	Just before extubation	0.490 ± 0.102^b c d	0.500 ± 0.108^b c d	0.88 (NS)
	Just after extubation	0.463 ± 0.088^b c d	0.463 ± 0.096^b c d	1
	30 min. after extubation	0.422 ± 0.056^d	0.416 ± 0.059	0.72 (NS)
Left eye	Baseline	0.370 ± 0.039^d	0.367 ± 0.038^d	0.77 (NS)
	After induction	0.414 ± 0.073^d	0.406 ± 0.071^d	0.74 (NS)
	5 min. after insufflations	0.489 ± 0.099^b c d	0.489 ± 0.097^b c d	1
	15 min. after insufflation	0.529 ± 0.109^b c	0.536 ± 0.112^b c	0.86 (NS)
	30 min. after insufflation	0.565 ± 0.108^b c	0.567 ± 0.104^b c	0.94 (NS)
	Just before extubation	0.499 ± 0.103^b c d	0.501 ± 0.107^b c d	0.95 (NS)
	Just after extubation	0.470 ± 0.090^b c d	0.465 ± 0.089^b c d	0.86 (NS)
	30 min. after extubation	0.415 ± 0.056^d	0.413 ± 0.058^d	0.91 (NS)

^aP value for F test (ANOVA) for comparing between ONS sagittal and transverse diameters

^bStatistically significant difference for P value for Post Hoc test (LSD) compared to baseline time point (P value < 0.05)

^cStatistically significant difference for P value for Post Hoc test (LSD) compared to after induction time point (P value < 0.05)

^dStatistically significant difference for P value for Post Hoc test (LSD) compared to 30 min after insufflation time point (P value < 0.05)

(NS) Statistically non-significant difference between both groups (P value >0.05)

Graph 1. Comparison of mean arterial blood pressure (MAP) at different time points.

^aP value for Post Hoc test (LSD) compared to baseline time point ^bP value for Post Hoc test (LSD) compared to after induction time point ^cP value for Post Hoc test (LSD) compared to 30 min after insufflation time point

Graph 2. Comparison of Heart rate at different time points.

^aP value for Post Hoc test (LSD) compared to baseline time point ^bP value for Post Hoc test (LSD) compared to after induction time point ^cP value for Post Hoc test (LSD) compared to 30 min after insufflation time point

Graph 3. Comparison of end-tidal partial pressure of CO₂ (EtCO₂) at different time points.

^aP value for Post Hoc test (LSD) compared to baseline time point ^bP value for Post Hoc test (LSD) compared to after induction time point ^cP value for Post Hoc test (LSD) compared to 30 min after insufflation time point