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Home / Equine Research Bank / Vet Ophthalmol / Evaluation of the Effect of Intravenous Mannitol and Hyperto...
Veterinary ophthalmology2025; doi: 10.1111/vop.70000

Evaluation of the Effect of Intravenous Mannitol and Hypertonic Saline on Intraocular Pressure and Biometry Parameters in Anesthetized Horses With Experimentally Increased Intracranial Pressure.

Abstract: To evaluate the effect of intravenous mannitol and hypertonic saline (HS) on intraocular pressure (IOP) and biometry parameters of horses with elevated intracranial pressure (ICP). Methods: Seven horses with normal ophthalmic exams were anesthetized and placed in lateral recumbency. A subarachnoid transducer was placed, and the head was lowered until ICP measured 40 mmHg +/- 2 mmHg. Five intravenous boluses of mannitol 20% (0.4 g/kg) or HS 7.2% (1 mL/kg) were administered, each 15 min apart. A 2-day washout period ensued, and the procedure was repeated with the other hyperosmotic agent. IOP via a TonoVet, axial length and vitreous chamber depth via biometry, and ICP via the subarachnoid transducer were monitored. Results: No significant correlation between ICP and IOP was identified. Estimated marginal mean (EMM) reduction in IOP (comparing values 5 min post bolus to values at bolus administration) following mannitol and HS was 2.4 mmHg and 0.4 mmHg, respectively. Mean axial length EMM decreased by and increased by 0.1 mm following mannitol and HS, respectively. Mean vitreous chamber depth EMM was unchanged and increased by 0.1 mm following mannitol and HS, respectively. The EMM of the second HS bolus demonstrated an increase of 0.8 mm (95% confidence interval 0.01-1.5 mm) in axial length (p < 0.048), though the remaining individual bolus assessments were not statistically significant. Conclusions: Intravenous mannitol and HS did not cause a significant change in IOP, axial length, or vitreous chamber depth in healthy, anesthetized, laterally recumbent horses in this experimental model of increased ICP.
© 2025 American College of Veterinary Ophthalmologists.
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Publication Date: 2025-02-11 PubMed ID: 39932045DOI: 10.1111/vop.70000Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article discusses an experiment conducted on anesthetized horses to find out the impact of intravenous mannitol and hypertonic saline on intraocular pressure and biometry parameters when there is increased intracranial pressure.

Objective and Methods of the Study

  • The primary objective of the study was to assess the effect of intravenous mannitol and hypertonic saline on intraocular pressure (IOP) and the biometric attributes of horses with high intracranial pressure (ICP).
  • Seven horses with normal ophthalmic exams were taken into consideration for this research. Each one was anesthetized and made to lie on their sides (lateral recumbency).
  • The researchers inserted a subarachnoid transducer and lowered the animal’s head until the ICP showed a reading of 40 mmHg +/- 2 mmHg.
  • This was followed by administering five intravenous boluses, each 15 minutes apart, of mannitol 20% (0.4 g/kg) or HS 7.2% (1 mL/kg). Each horse underwent a 2-day washout period and then the process was repeated using the other hyperosmotic agent.
  • The researchers monitored the intraocular pressure using a TonoVet, the axial length and vitreous chamber depth via biometry, and ICP via the subarachnoid transducer, throughout this study.

Results of the Study

  • No significant correlation was found between ICP and IOP during the study.
  • The estimated marginal mean (EMM) reduction in IOP was 2.4 mmHg and 0.4 mmHg, respectively, post administering mannitol and HS.
  • The mean axial length EMM showed a decrease of 0.1 mm when mannitol was administered and increased by 0.1 mm with HS administration.
  • There was no change in the mean vitreous chamber depth EMM post mannitol, while it increased by 0.1 mm with HS.
  • The second HS bolus had shown an increase in axial length by 0.8 mm, however, the other individual bolus assessments were not statistically significant.

Conclusions Drawn from the Study

  • The researchers did not observe any considerable change in intraocular pressure, axial length or vitreous chamber depth in anesthetized horses that were placed laterally.
  • This conclusion is based on the outcomes observed in this experimental model with increased ICP, when the horses were treated with intravenous mannitol and hypertonic saline.

Cite This Article

APA
Bercovitz GR, Sullivan SN, Reed RA, Ryan CA, Diehl KA. (2025). Evaluation of the Effect of Intravenous Mannitol and Hypertonic Saline on Intraocular Pressure and Biometry Parameters in Anesthetized Horses With Experimentally Increased Intracranial Pressure. Vet Ophthalmol. https://doi.org/10.1111/vop.70000

Publication

Veterinary ophthalmology
ISSN: 1463-5224
NlmUniqueID: 100887377
Country: England
Language: English

Researcher Affiliations

Bercovitz, Genia R
  • Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA.
Sullivan, Stasia N
  • Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA.
Reed, Rachel A
  • Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA.
Ryan, Clare A
  • Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA.
Diehl, Kathryn A
  • Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA.

Grant Funding

  • 327 RAQRT000140950A / American Quarter Horse Foundation

References

This article includes 29 references
  1. Westermeyer HD, Wilkie DA, Gemensky‐Metzler AJ. Glaucoma. vol. 1, 4th ed., 543–563, 2022.
  2. de Linde Henriksen M, La Croix N, Wilkie DA. Glaucoma With Descemet's Membrane Detachment in Five Horses. Veterinary Ophthalmology 20, no. 3 (2017): 273–279.
    doi: 10.1111/vop.12388google scholar: lookup
  3. Stonex TM, Watanabe N, Robertson JB, Westermeyer HD. Equine Pectinate Ligament Descemetization Is Associated With Age. Veterinary Ophthalmology 26, no. 3 (2023): 225–230.
    doi: 10.1111/vop.13071google scholar: lookup
  4. Komáromy AM, Garg CD, Ying GS, Liu C. Effect of Head Position on Intraocular Pressure in Horses. American Journal of Veterinary Research 67, no. 7 (2006): 1232–1235.
    doi: 10.2460/ajvr.67.7.1232google scholar: lookup
  5. Monk CS, Brooks D, Granone TD, Garcia‐Pereira F, Melesko A, Plummer CE. Measurement of Intraocular Pressure in Healthy Anesthetized Horses During Hoisting. Veterinary Anesthesia and Analgesia 44, no. 3 (2017): 502–508.
    doi: 10.1016/j.vaa.2016.10.001google scholar: lookup
  6. Meekins JM, McMurphy RM, Roush JK. The Effect of Body Position on Intraocular Pressure in Anesthetized Horses. Veterinary Ophthalmology 23, no. 4 (2020): 668–673.
    doi: 10.1111/vop.12769google scholar: lookup
  7. Alling CR, Cremer J, Liu C, Lewin AC, Camacho‐Luna P, Carter RT. Effect of Multiple Head Positions on Intraocular Pressure in Healthy, Anesthetized Horses During Hoisting. Veterinary Ophthalmology 24, no. 1 (2020): 71–79.
    doi: 10.1111/vop.12849google scholar: lookup
  8. Joyner RL, Liu CC, Cremer J, Carter R, Lewin AC. Intraocular Pressure Following Four Different Intravenous Sedation Protocols in Normal Horses. Equine Veterinary Journal 53, no. 3 (2020): 612–617.
    doi: 10.1111/evj.13336google scholar: lookup
  9. Lashutka MK, Chandra A, Murray H, Phillips G, Hiestand B. The Relationship of Intraocular Pressure to Intracranial Pressure. Annals of Emergency Medicine 43, no. 5 (2004): 585–591.
    doi: 10.1016/j.annemergmed.2003.12.006google scholar: lookup
  10. Ghate D, Kedar S, Havens S. The Effects of Acute Intracranial Pressure Changes on the Episcleral Venous Pressure, Retinal Vein Diameter, and Intraocular Pressure in a Pig Model. Current Eye Research 46, no. 4 (2020): 524–531.
    doi: 10.1080/02713683.2020.1805769google scholar: lookup
  11. Plummer C. Clinical Pharmacological and Therapeutics Part 5 Medical Therapy for Glaucoma. 451–478, 2021.
  12. Krupin T, Podos SM, Becker B. Alteration of Intraocular Pressure After Third Ventricle Injections of Osmotic Agents. American Journal of Ophthalmology 76, no. 6 (1973): 948–952.
    doi: 10.1016/0002‐9394(73)90087‐1google scholar: lookup
  13. Lorimer DW, Hakanson NE, Pion PD, Merideth RE. The Effect of Intravenous Mannitol or Oral Glycerol on Intraocular Pressure in Dogs. Cornell Veterinarian 79, no. 3 (1989): 249–258.
  14. Volopich S, Mosing M, Auer U, Nell B. Comparison of the Effect of Hypertonic Hydroxyethyl Starch and Mannitol on the Intraocular Pressure in Healthy Normotensive Dogs and the Effect of Hypertonic Hydroxyethyl Starch on the Intraocular Pressure in Dogs With Primary Glaucoma. Veterinary Ophthalmology 9, no. 4 (2006): 239–244.
    doi: 10.1111/j.1463‐5224.2006.00467.xgoogle scholar: lookup
  15. Sawada T, Nakamura J, Nishida Y, Kani K, Morikawa S, Inubushi T. Magnetic Resonance Imaging Studies of the Volume of the Rabbit Eye With Intravenous Mannitol. Current Eye Research 25, no. 3 (2002): 173–177.
    doi: 10.1076/ceyr.25.3.173.13474google scholar: lookup
  16. Davson H, Thomassen TL. The Effect of Intravenous Infusion of Hypertonic Saline on the Intra‐Ocular Pressure. British Journal of Ophthalmology 34, no. 6 (1950): 355–359.
    doi: 10.1136/bjo.34.6.355google scholar: lookup
  17. Mauger TF, Nye CN, Boyle KA. Intraocular Pressure, Anterior Chamber Depth and Axial Length Following Intravenous Mannitol. Journal of Ocular Pharmacology and Therapeutics 16, no. 6 (2000): 591–594.
    doi: 10.1089/jop.2000.16.591google scholar: lookup
  18. Fielding CL, Magdesian KG. A Comparison of Hypertonic (7.2%) and Isotonic (0.9%) Saline for Fluid Resuscitation in Horses: A Randomized, Double‐Blinded, Clinical Trial. Journal of Veterinary Internal Medicine 25 (2011): 1138–1143.
    doi: 10.1111/j.1939‐1676.2011.00789google scholar: lookup
  19. Feary DJ, Magdesian KG, Aleman MA, Rhodes DM. Traumatic Brain Injury in Horses: 34 Cases (1994‐2004). Journal of the American Veterinary Medical Association 231, no. 2 (2007): 259–266.
    doi: 10.2460/javma.231.2.259google scholar: lookup
  20. Cornelisse CJ, Schott H, Lowrie CT, Rosenstein DS. Successful Treatment of Intracranial Abscesses in 2 Horses. Journal of Veterinary Internal Medicine 15, no. 5 (2001): 494–500.
    doi: 10.1892/0891‐6640(2001)015google scholar: lookup
  21. Bramski JH, Reed RA, Diehl KA, Epstein KL, Ryan CA. Evaluation of Transpalpebral Ultrasonographic Measurement of Optic Nerve Sheath Diameter for Indirect Assessment of Intracranial Pressure in Anesthetized and Standing Healthy Adult Horses. Journal of Veterinary Emergency and Critical Care 31, no. 3 (2021): 315–322.
    doi: 10.1111/vec.13061google scholar: lookup
  22. Gilroy BA. Intraocular and Cardiopulmonary Effects of Low‐Dose Mannitol in the Dog. Veterinary Surgery 15, no. 4 (1986): 342–344.
    doi: 10.1111/j.1532‐950x.1986.tb00240.xgoogle scholar: lookup
  23. Herbig L, Eule JC. Central Corneal Thickness Measurements and Ultrasonographic Study of the Growing Equine Eye. Veterinary Ophthalmology 18, no. 6 (2015): 462–471.
    doi: 10.1111/vop.12252google scholar: lookup
  24. McMullen RJ, Gilger BC. Keratometry, Biometry and Prediction of Intraocular Lens Power in the Equine Eye. Veterinary Ophthalmology 9, no. 5 (2006): 357–360.
    doi: 10.1111/j.1463‐5224.2006.00493.xgoogle scholar: lookup
  25. Mouney M, Townsend W, Moore G. Association of Height, Body Weight, Age, and Corneal Diameter With Calculated Intraocular Lens Strength of Adult Horses. American Journal of Veterinary Research 73, no. 12 (2012): 1977–1982.
    doi: 10.2460/ajvr.73.12.1977google scholar: lookup
  26. Ilie LA, Thomovsky EJ, Johnson PA. Relationship Between Intracranial Pressure as Measured by an Epidural Intracranial Pressure Monitoring System and Optic Nerve Sheath Diameter in Healthy Dogs. American Journal of Veterinary Research 76, no. 8 (2015): 724–731.
    doi: 10.2460/ajvr.76.8.724google scholar: lookup
  27. Evangelisti MA, Carta G, Burrai GP. Repeatability of Ultrasound Examination of the Optic Nerve Sheath Diameter in the Adult Cat: Comparison Between Healthy Cats and Cats Suffering From Presumed Intracranial Hypertension. Journal of Feline Medicine and Surgery 22, no. 10 (2020): 959–965.
    doi: 10.1177/1098612x19898006google scholar: lookup
  28. Brosnan RJ, LeCouteur RA, Steffey EP, Imai A, Kortz GD. Direct Measurement of Intracranial Pressure in Adult Horses. American Journal of Veterinary Research 63, no. 9 (2002): 1252–1256.
    doi: 10.2460/ajvr.2002.63.1252google scholar: lookup
  29. Ferreira TH, Brosnan RJ, Shilo‐Benjamini Y, Moore SB, Hollingsworth SR. Effects of Ketamine, Propofol, or Thiopental Administration on Intraocular Pressure and Qualities of Induction of and Recovery From Anesthesia in Horses. American Journal of Veterinary Research 74, no. 8 (2013): 1070–1077.
    doi: 10.2460/ajvr.74.8.1070google scholar: lookup

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