The increase of intra-abdominal pressure can affect intraocular pressure

The Effect of Esophagogastroduodenoscopy on Intraocular Pressure

BACKGROUND

Esophagogastroduodenoscopy (EGD) is an endoscopic examination of the upper gastrointestinal tract that requires insufflation with gas, leading to intra-abdominal hypertension (IAH). There is evidence suggesting that IAH positively correlates with intracranial pressure (ICP) and possibly with intraocular pressure (IOP). The aim of this study was to examine the effect of a routine screening EGD on the IOP.

METHODS

In this observational study, 25 patients were recruited; 15 males with a mean age of 50 ± 18 years and 10 females with a mean age of 45 ± 14 years. EGD was conducted under sedation in 21 subjects. Both eyes' IOP measurements were performed using Tonopen Avia in the sitting and left lateral decubitus positions before sedation and the start of EGD, and subsequently in the left lateral decubitus position when the endoscope reached the duodenum (D2) and at the end of the procedure. The final measurement was performed in the sitting position 10 min after the end of the procedure.

RESULTS

The mean IOP in the sitting position was 15.16 ± 2.27 mmHg, and in the left lateral decubitus position, 15.68 ± 2.82 mmHg. When the gastroscope entered the D2, it was 21.84 ± 6.55 mmHg, at the end of the procedure, 15.80 ± 3.25 mmHg, and 10 min later, 13.12 ± 3.63 mmHg. There was a statistically significant IOP increase when the gastroscope entered the duodenum (p < 0.01). At the end of the gastroscopy, the IOP significantly decreased compared to the one registered when the gastroscope entered the D2 (p < 0.001) and it became similar to the values measured before the EGD, in the same left lateral decubitus position (p > 0.05).

CONCLUSION

Significant changes in IOP were observed during the EGD. IOP fluctuations during EGD should be taken into account, especially in patients that need repeated EGDs during their life or in patients with glaucoma. Further studies are needed to better understand the short-effect and long-effect influence of an IOP increase in these patients.

3D finite-element modeling of vascular adaptation after endovascular aneurysm repair

Aneurysm shrinkage is clinically observed after successful endovascular aortic aneurysm repair (EVAR). However, global understanding of post-operative aneurysm evolutions remains weak. In this work, we propose to study these effects using numerical simulation. We set up a 3D finite-element model of post-EVAR vascular adaptation within an open-source finite-element code, which was initially developed for growth and remodeling (G&R). We modeled the endograft with a set of uniaxial prestrained springs that apply radial forces on the inner surface of the artery. Constitutive equations, momentum balance equations, and equations related to the mechanobiology of the artery were formulated based on the homogenized constrained mixture theory. We performed a sensitivity analysis by varying different selected parameters, namely oversizing and compliance of the stent-graft, gain parameters related to collagen G&R, and the residual pressure in the aneurysm sac. This permitted us to evaluate how each factor influences post-EVAR vascular adaptation. It was found that oversizing, compliance or gain parameters have a limited influence compared to that of the residual pressure in the aneurysm sac, which was found to play a critical role in the stability of aneurysm after stent-graft implantation. An excessive residual pressure larger than 50 mmHg can induce a continuous expansion of the aneurysm while a moderate residual pressure below this critical threshold yields continuous shrinkage of the aneurysm. Moreover, it was found that elderly patients, with relatively lower amounts of remnant elastin in the arterial wall, are more sensitive to the effect of residual pressure. Therefore, these results show that elderly patients may present a higher potential risk of aortic sac expansion due to intra-aneurysm sac pressure after EVAR than younger patients.

Effect of intra-abdominal hypertension on the intraocular pressure of the conscious dogs

This study was performed to evaluate the effect of intra-abdominal pressure (IAP) on intraocular pressure (IOP) in conscious dog models using a balloon technique to generate intra-abdominal hypertension. Six healthy dogs without ocular abnormalities were evaluated in this study. A balloon device was placed in the intra-abdominal cavity. The abdomen was insufflated to IAP levels of 15 and 25 mmHg using the balloon device. Intraocular pressure was measured at baseline, at IAP levels of 15 and 25 mmHg, and after decompression. In comparison with the mean baseline IOP (15.1 ± 2.0 mmHg), there was a significant increase in IOP at IAP levels of 15 mmHg (20.0 ± 2.1 mmHg) and 25 mmHg (19.9 ± 2.2 mmHg), corresponding to a 32.4% and 31.7% increase from baseline IOP, respectively. The mean IOP after decompression (14.8 ± 1.7 mmHg) was significantly lower compared to those at IAP levels of 15 and 25 mmHg. The present findings demonstrate that increased IAP has a clinically significant effect on IOP in dogs under conscious conditions. Although more research is needed to determine of increased IAP on IOP, these findings suggest that increased IAP leads to mild and reversible increase in IOP.

Clinical Anatomy of the Extradural Neural Axis Compartment: A Literature Review

OBJECTIVE

The extradural neural axis compartment (EDNAC) is an adipovenous zone located between the meningeal and endosteal layers of the dura and has been minimally investigated. It runs along the neuraxis from the orbits down to the coccyx and contains fat, valveless veins, arteries, and nerves. In the present review, we have outlined the current knowledge regarding the structural and functional significance of the EDNAC.

METHODS

We performed a narrative review of the reported EDNAC data.

RESULTS

The EDNAC can be organized into 4 regional enlargements along its length: the orbital, lateral sellar, clival, and spinal segments, with a lateral sellar orbital junction linking the orbital and lateral sellar segments. The orbital EDNAC facilitates the movement of the eyeball and elsewhere allows limited motility for the meningeal dura. The major nerves and vessels are cushioned and supported by the EDNAC. Increased intra-abdominal pressure will also be conveyed along the spinal EDNAC, causing increased venous pressure in the spine and cranium. From a pathological perspective, the EDNAC functions as a low-resistance, extradural passageway that might facilitate tumor encroachment and expansion.

CONCLUSIONS

Clinicians should be aware of the extent and significance of the EDNAC, which could affect skull base and spine surgery, and have an understanding of the tumor spread pathways and growth patterns. Comparatively little research has focused on the EDNAC since its initial description. Therefore, future investigations are required to provide more information on this underappreciated component of neuraxial anatomy.

Does Bariatric Surgery Affect Intraocular Pressure?

PURPOSE

The effect of body mass index (BMI) reduction following bariatric surgery on intraocular pressure (IOP) is not well established. We evaluated association between BMI reduction and IOP measurements and other ocular and metabolic parameters 1 year after bariatric surgery.

MATERIALS AND METHODS

A retrospective study with over 1-year follow-up on patients who underwent weight reduction bariatric surgery between January 2016 and December 2016 at Wolfson Medical Center, Israel. Patient data was extracted from outpatient's bariatric and ocular clinic records. Metabolic, ocular, and clinical parameters were assessed including BMI changes, IOP, central corneal and retinal nerve fiber layer thickness, optical coherence tomography, and biometry results.

RESULTS

Of 22 bariatric surgery patients, 15 underwent laparoscopic sleeve gastrectomy (LSG) and 7 laparoscopic mini gastric bypass (MGB). All were followed up for over 1 year after surgery. Average BMI decreased from 41.9 ± 7.3 to 25.5 ± 5.7 kg/m² at 1-year follow-up (p < 0.001). Mean IOP decreased significantly by 21% after 1 year (p < 0.001). Decrease in IOP 1 year after surgery was correlated with decrease in IOP at 3-month follow-up (r = 0.677, p = 0.001), preoperative IOP (r = 0.837, p < 0.001), and corneal thickness (r = 0.589, p = 0.006), with no correlation between reduction in IOP and baseline weight, BMI, or the reduction in either (p > 0.05). Central corneal thickness and retinal nerve fiber layer thickness were also significantly decreased (p = 0.038) and (p = 0.018), respectively.

CONCLUSION

BMI reduction achieved by bariatric surgery was associated with significant and continued decline in IOP beyond 1 year after surgery. Clinical implications highlight the importance of considering bariatric surgery in patients with ocular hypertension.

Prospective evaluation of visual function in patients with ocular diseases after robot-assisted laparoscopic prostatectomy

OBJECTIVES

To investigate intraocular pressure and visual function in patients with ocular diseases undergoing robot-assisted laparoscopic prostatectomy.

METHODS

We carried out a prospective clinical study of patients undergoing robot-assisted laparoscopic prostatectomy for localized prostate cancer at The University of Tokyo Hospital from December 2015 to March 2017. An ophthalmologist measured intraocular pressure, and carried out visual field testing at 0-2 months before and 7 days after robot-assisted laparoscopic prostatectomy. During the surgery, an anesthesiologist measured intraocular pressure at specified time points.

RESULTS

A total of 110 patients were enrolled and 98 eligible patients were analyzed; 37 were diagnosed with ocular diseases before robotic-assisted laparoscopic prostatectomy (17 with glaucoma, 20 with other ocular diseases). Intraocular pressure significantly increased during robot-assisted laparoscopic prostatectomy. Transient postoperative visual field defect was detected in 24 eyes of 17 patients, including six patients with ocular diseases at 7 days after surgery. At 3 months after surgery, one of 34 glaucomatous eyes and one of 40 eyes with non-glaucomatous ocular diseases continued to show visual field defect, although visual field defect in the remaining patients recovered to preoperative conditions within 3 months.

CONCLUSIONS

Our findings suggest that robot-assisted laparoscopic prostatectomy can be safely carried out in patients with ocular diseases, even those with glaucoma, after precautionary consultation with an ophthalmologist.

The effect of colonoscopy on intraocular pressure: an observational prospective study

PURPOSE

Colonoscopy is an endoscopic examination of the bowel. It requires insufflation of the large bowel lumen with gas which leads to intraabdominal hypertension (IAH). There is evidence suggesting that IAH positively correlates with intracranial pressure (ICP) and possibly with intraocular pressure (IOP). The aim of this study was to examine the effect of routine screening colonoscopy performed under sedation on the IOP in healthy individuals.

PATIENTS AND METHODS

This was a prospective, single site, observational study. Healthy adults undergoing routine colonoscopy performed under sedation including propofol, fentanyl, and midazolam were recruited. Right eye IOP measurements were performed using Tonopen XL® in a left decubitus position at 5 time points during the procedure. Statistical analysis was performed using Student's t-test for paired samples.

RESULTS

Twenty-three Caucasians were recruited. There are 14 males (60%) with a mean age of 60.4 ± 10.4 years (range 36-74). Colonoscopy was conducted under sedation and completed in 22 subjects. Mean baseline IOP was 19.9 ± 4.7 mmHg, 15.8 ± 4.8 mmHg immediately after sedation, 13.5 ± 2.3 mmHg when the colonoscope had reached the cecum, 15.4 ± 5.0 mmHg 5 min after colonoscopy beginning, and 16.5 ± 5.5 mmHg when located in the rectum. The IOP reduction during the procedure was statistically significant (P < 0.01).

CONCLUSION

Routine colonoscopy performed under sedation using propofol, fentanyl, and midazolam does not increase the IOP in healthy adults.

Effects of a multifaceted individualized pneumoperitoneum strategy in elderly patients undergoing laparoscopic colorectal surgery: A retrospective study

BACKGROUND

Laparoscopic colorectal surgery may adversely affect respiration, circulation, and acid-base balance in elderly patients, owing to the relatively long duration of CO2 absorption. We conducted this retrospective study to determine the safety and efficacy of warmed, humidified CO2 pneumoperitoneum in elderly patients undergoing laparoscopic colorectal surgery.

METHODS

We enrolled 245 patients between January 2016 and August 2018.The experimental group (warming and humidification group [WH]) received warmed (37°C), humidified (98%) insufflation of CO2, and the control group (cold, dry CO2/control group [CD]) received standard CO2 (19°C, 0%). All other aspects of patient care were standardized. Intraoperative hemodynamic data, arterial blood pH, and lactic acid levels were recorded. We also recorded intra-abdominal pressure, incidence of shivering 1 hour after surgery, satisfaction scores of patients and surgeons 24 hours after surgery, times to first flatus/defecation, first bowel movement, and tolerance of semiliquid food, discharge time, and incidence of vomiting, diarrhea, and surgical site infections.

RESULTS

Compared with the WH group, heart rate and mean arterial pressure were significantly higher from T3 to T8 (P < .05), lactic acid levels were significantly higher from T4 to T9 (P < .05), and recovery time in the post-anesthesia care unit (PACU) was significantly longer in the CD group (P < .05). Patient and surgeon satisfaction scores were significantly higher in the WH group than the CD group (P < .05). In addition, the times to first flatus/defecation and bowel movement were significantly longer in the CD group (P < .05). No significant differences were noted between the groups in the time to tolerance of semiliquid food and time of discharge (P > .05). The incidence of vomiting, diarrhea, and shivering was significantly lower in the WH group (P < .05). The number of patients with a shivering grade of 0 was significantly higher in the WH group, whereas the number with a shivering grade of 3 was significantly higher in the CD group (P < .05).

CONCLUSION

Warmed, humidified insufflation of CO2 in elderly patients undergoing laparoscopic colorectal surgery could stabilize hemodynamics, and reduce lactic acid levels, recovery time in the PACU, and the incidence of acute gastrointestinal injury-related symptoms.

Systemic Disease and Long-term Intraocular Pressure Mean, Peak, and Variability in Nonglaucomatous Eyes

PURPOSE

Elevated intraocular pressure (IOP) is a well-known risk factor in glaucoma development and progression. As most glaucoma risk factors are not modifiable, IOP remains the sole focus of medical and surgical therapy. Identifying modifiable factors and their effects on IOP, such as systemic diseases, is therefore of interest. The objective is to assess the long-term, longitudinal relationship between systemic diseases and IOP mean, peak, and variability, including diabetes, hypertension, body mass index (BMI), and smoking status.

DESIGN

Secondary analysis of randomized clinical trial data.

METHODS

Longitudinal IOP and systemic disease data from the Age-Related Eye Disease Study (AREDS), a randomized clinical trial of high-dose antioxidants, was analyzed.

STUDY POPULATION

A total of 3909 older participants without a reported diagnosis of glaucoma or glaucoma treatment during AREDS with up to 12 years of annual IOP and systemic disease data.

MAIN OUTCOME MEASURES

Independent systemic disease risk factors associated with IOP.

RESULTS

Univariate analysis identified numerous systemic disease factors associated with IOP mean, peak, and variability. Longitudinal adjusted models identified diabetes, obesity, and systolic hypertension as significantly associated with increased IOP, while systemic beta-blocker use was inversely associated.

CONCLUSIONS

Results demonstrate a relationship between multiple systemic diseases and IOP; moreover, they demonstrate that systemic diseases influence additional parameters beyond mean IOP, such as IOP peak and variability. Although only to be taken within the context of IOP, these population-level trends reveal potentially modifiable factors in IOP control, and are particularly important in the context of increasing obesity and diabetes prevalence rates in American adults.

Reduction of intraocular pressure after bariatric surgery

PURPOSE

To investigate the effects of bariatric surgery on intraocular pressure (IOP).

METHODS

We prospectively enroled consecutive obese patients who underwent a laparoscopic sleeve gastrectomy procedure. We measured IOP prior to and 3-6 months following surgery and recorded medical and demographical parameters.

RESULTS

Thirty-two patients completed all evaluations. Mean age was 40.5 ± 12 and 24 (75%) were men. Following surgery, mean body-mass index (BMI) decreased from 42 ± 6 to 31 ± 8 (p < 0.001). The mean IOP decreased from 16.9 ± 4 mmHg to 14.1 ± 3 mmHg (p < 0.001). The extent of IOP reduction was correlated with the baseline IOP (Pearson r = 0.737, p < 0.001) and central corneal thickness (Pearson r = 0.453, p = 0.010).

CONCLUSION

In a cohort of obese individuals undergoing sleeve gastrectomy, there was a significant decrease in IOP measured 3-6 months after the procedure. Our results suggest that significant weight loss could have beneficial effects on IOP in obese individuals with ocular hypertension which might enable avoidance of antiglaucoma medications. The high likelihood of a reduction in IOP should be taken into account when considering bariatric surgery in such patients.

Are you seeing this: the impact of steep Trendelenburg position during robot-assisted laparoscopic radical prostatectomy on intraocular pressure: a brief review of the literature

With the increasing popularity, frequency, and acceptance of the robotic-assisted laparoscopic radical prostatectomy procedure, an awareness of unique intra- and postoperative complications is heightened, including that of increases in intraocular pressure. The steep Trendelenburg positioning required for operative exposure has been shown to increase this value. While the literature is infrequent and undeveloped, certain anesthetic parameters including deep neuromuscular blockade, modified positioning, and the use of dexmedetomidine have been shown to have mild-to-modest decreases in intraocular pressure for baseline. In the four randomized control trials and four observational studies that were found via PubMed/Medline search, the aforementioned techniques demonstrate some preliminary evidence of operative considerations in this unique patient population. These modifications may prove to have even greater significance in patients with pre-existing ophthalmologic pathologies, such as glaucoma, which were excluded from the studies' analyses. This review summarizes the early literature obtained in this subject, with the intent of emphasizing the initial hypotheses and identifying areas for future study.

The effect of single incision laparoscopic cholecystectomy on systemic oxidative stress: a prospective clinical trial

Purpose

Single incision laparoscopic cholecystectomy (SILC) has become a more frequently performed method for benign gallbladder diseases all over the world. The effects of SILC technique on oxidative stress have not been well documented. The aim of this study was to evaluate the effect of laparoscopic cholecystectomy techniques on systemic oxidative stress by using ischemia modified albumin (IMA).

Methods

In total, 70 patients who had been diagnosed with benign gallbladder pathology were enrolled for this prospective study. Twenty-one patients underwent SILC and 49 patients underwent laparoscopic cholecystectomy (LC). All operations were performed under a standard anesthesia protocol. Serum IMA levels were analysed before operation, 45 minutes and 24 hours after operation.

Results

Demographics and preoperative characteristics of the patients were similiar in each group. The mean duration of operation was 37.5 ± 12.5 and 44.6 ± 14.3 minutes in LC and SILC group, respectively. In both groups, there was no statistically significant difference in hospital stay, operative time, or conversion to open surgery. Operative technique did not effect the 45th minute and 24th hour IMA levels. However, prolonged operative time (>30 minutes) caused an early increase in the level of IMA. Twenty-fourth hour IMA levels were not different.

Conclusion

SILC is an effective and safe surgical prosedure for benign gallbladder diseases. Independent of the surgical technique for cholecystectomy, the prolonged operative time could increase the tissue ischemia.

Intraocular Pressure Changes With Positioning During Laparoscopy

Background and Objectives:

Pneumoperitoneum during laparoscopy can produce changes in intraocular pressure (IOP) that may be influenced by several factors. In this study, we investigated changes in IOP during laparoscopy with different positioning.

Methods:

We recruited adult patients without eye disease scheduled to undergo laparoscopic operation requiring a reverse Trendelenburg tilt (rTr; group A; n = 20) or Trendelenburg tilt (Tr; Group B; n = 20). IOP was measured at 7 time points (T1–T7). All procedures were performed with standardized anaesthetic protocol. Mean arterial pressure (MAP), heart rate (HR), peak and plateau airway pressure, and end-tidal carbon dioxide (ETCO₂) measurements were taken at each time point.

Results:

Both groups were similar in age, sex, mean body mass index (BMI), duration of surgery, and preoperative IOP. A decrease in IOP was observed in both groups after induction of anaesthesia (T2), whereas induction of pneumoperitoneum produced a mild increase in IOP (T3) in both groups. The Trendelenburg tilt produced IOP elevations in 80% of patients compared to 45% after the reverse Trendelenburg tilt (P = .012). A significant IOP increase of 5 mm Hg or more was recorded in 3 (15%) patients in the Trendelenburg tilt group and in none in the reverse Trendelenburg group. At T7, IOP had returned to preoperative levels in all but 3 (15%) in the Trendelenburg and 1 (5%) in the reverse Trendelenburg group. Reversible changes were observed in the MAP, HR, ETCO₂, and airway pressures in both groups.

Conclusions:

IOP changes induced by laparoscopy are realigned after evacuation of pneumoperitoneum. A Trendelenburg tilt however produced significant changes that may require careful patient monitoring during laparoscopic procedures.