Dangers of Yoga,
Keeping Your Head Upside Down for Long Periods of Time,
and
Prostatectomy with Steep Trendelenburg Surgical Positioning (Your Head is Tilted Down)
Generally in most healthy patients, there is minimal if any risk of keeping your head below your heart for a prolonged period of time.
As this article below points out however, if you engage in particular Yoga positions or plan to have a Prostatectomy with Steep Trendelenburg (Your Head is Tilted Down) Surgical Positioning, you need to know if you have a risk of glaucoma, a family history of glaucoma, or ocular hypertension (eye pressure higher than 21mmHg adjusted for corneal thickness [with a pachymetry].
There have been case reports of loss of vision in patients who have glaucoma and have had their head tilted down for a particular period of time. The approximate risk has been reported to be between 0.00008% to 0.2% for spinal or cardiac surgeries. Since some spinal and thoracic surgeons may not discuss this risk with patients, it is important for glaucoma patients to know of this risk.
If you have glaucoma or are a glaucoma-suspect (ie, your MD is following you to be sure your nerve does not begin to show damage of glaucoma), then you should avoid positions where your head is below your heart for a prolonged period of time.
IOP increases with steep Trendelenburg positioning during robotic-assisted laparoscopy
Urology patients with any pre-existing glaucoma or severe family history of glaucoma may be particularly at risk.
Patients with healthy eyes who underwent robotic-assisted laparoscopy with steep Trendelenburg surgical positioning experienced a significant elevation in IOP, according to a prospective cohort study.
Steep Trendelenburg positioning for such a procedure consists of a supine position, with feet above the head, at an angle of inclination between 30° and 45°.
“Given the increased use of steep Trendelenburg positioning in robotic prostatectomy surgeries over the past decade, along with many case reports of postoperative vision loss, our urology and ophthalmology teams together identified the need for a quality case-controlled study measuring the evolution of eye pressures during these surgeries,” principal investigatorTodd J. Mondzelewski, MD, said.
Study design and results
The study, which appeared in the Journal of Glaucoma, reported on 39 patients who were divided into three groups. Group 1 (18 patients) underwent robotic-assisted laparoscopy in the steep Trendelenburg position (30° angle), with all but one case being a radical prostatectomy. Group 2 (12 patients) was an open surgical control group in which all patients remained horizontal during the procedure. Group 3 (nine patients) was a laparoscopic control group that was also positioned horizontally.
Despite a similar baseline IOP for the three groups, the IOP plateau from 60 minutes to the conclusion of the case was 29.9 mm Hg, 19.9 mm Hg and 22.8 mm Hg, respectively.
“There are remarkable increases in IOP, especially after several hours of steep positioning,” Mondzelewski, assistant residency program director of ophthalmology at Naval Medical Center San Diego, told Ocular Surgery News. While the study enrolled patients without existing eye disease, “this is a serious problem for any patient with known glaucoma, vascular disease or possibly for ocular hypertensives, and anyone already on pressure-lowering therapy.”
Mondzelewski said that the negative IOP effect of steep positioning is probably due to increased episcleral venous pressure, which in turn increases IOP. As for better screening of candidates, “we feel these IOP changes would likely occur in any group or individual undergoing steep positioning procedures; however, those with pre-existing glaucomatous disease may experience higher IOP elevations,” he said.
Although there are slight variations in the degree of steep Trendelenburg positioning among centers performing robotic prostatectomies, “given current methods, there is no way to eliminate the need for such positioning, and therefore IOP increases would likely persist,” Mondzelewski said.
Robotic surgery rate increasing
Open prostatectomy procedures are rarely performed today due to the notable advantages of the robotic procedure, including smaller incisions, less pain and a reduced surgical site infection rate.
“We feel, however, that for a patient with severe glaucoma who requires a prostatectomy, there must be a conversation between the patient, ophthalmologist and urologist given the known significant IOP rise during surgery persisting to at least 1 day postop and the potential risk for progressive vision loss or blindness,” Mondzelewski said. “This reality must be discussed with patients preoperatively, and all urology patients undergoing these procedures should be queried as to whether they have any pre-existing or severe family history of glaucoma.”
Mondzelewski said further study is needed to ascertain the impact of these severe IOP rises on populations with pre-existing eye disease.
“The degree of visual field loss and quality of life impact could then be assessed,” he said.
Mondzelewski and colleagues are interested in a follow-up study to determine whether IOP-lowering therapy instilled before steep Trendelenburg positioning would blunt the significant increase in IOP.
The springboard for a second follow-up study is the substantial overlap between older men who are offered or need prostatectomy and older men with pre-existing or developing glaucoma. The study would consist of older men with known eye disease to determine the severity of IOP increase during procedures using steep Trendelenburg who received IOP-lowering therapy before the surgery. – by Bob Kronemyer
- Reference:
- Mondzelewski TJ, et al. J Glaucoma. 2015;doi:10.1097/IJG.0000000000000302.
- http://www.healio.com/ophthalmology/glaucoma/news/print/ocular-surgery-news/%7Be3c0d764-5a57-4c93-a67b-8c96a3a8560c%7D/iop-increases-with-steep-trendelenburg-positioning-during-robotic-assisted-laparoscopy