Effects of Dexmedetomidine Alone and Combined with Tramadol on Intraocular Pressure, Pupil Size, and Tear Production in Cats: A Randomized Controlled Study

Yıl 2026, Cilt: 37 Sayı: 1, 87 - 91, 29.03.2026

Ayşe Gölgeli Bedir , Büşra Baykal , Ömer Tarık Orhun , Ferda Turgut , Yakup Kocaman

https://doi.org/10.36483/vanvetj.1843931

https://izlik.org/JA34LB45XW

Öz

This present study was designed to evaluate the impact of intramuscular dexmedetomidine, alone or combined with subcutaneous tramadol, on intraocular pressure (IOP), pupil size (PS), and tear secretion (TS) in healthy cats. Thirty healthy cats (n=30) were randomly assigned to two groups (n=15/group). Cats received either dexmedetomidine alone (Dex; 25 µg/kg IM) or dexmedetomidine plus tramadol (Dex-Tra; tramadol 2 mg/kg SC + dexmedetomidine 25 µg/kg IM). IOP, PS, and TS were recorded at baseline (T0) and 5, 15, and 30 minutes post-administration (T5, T15, T30). Within the Dex group, IOP decreased significantly from T0 to T30, and PS increased from T5 to T15, returning to baseline by T30 (p<0.05). Between groups, IOP at T5 was lower in Dex than Dex-Tra (p<0.05), with no between-group differences at T15 or T30 (p>0.05). No statistically significant differences were observed between groups for PS or TS at any measured time point (p>0.05). Both protocols reduced TS over time. Dexmedetomidine alone produced ocular hypotension and a transient increase in PS; co-administration with tramadol attenuated these effects. As both regimens decreased tear secretion, clinicians should consider potential impacts on tonometry, ocular surface integrity, and perioperative ophthalmic management when selecting sedation protocols.

Anahtar Kelimeler

Cat , Dexmedetomidine , Intraocular pressure , Pupil size , Tramadol

Etik Beyan

This study was approved by the Atatürk University Local Ethics Committee for Animal Experiments (HADYEK) with the decision dated 24 September 2025, Decision No: 231, Session No: 2025/11 (Official correspondence number: E-75296309-050.01.04-2500316654, dated 25.09.2025). The research title submitted to the ethics committee was: “Effects of Dexmedetomidine Alone and in Combination with Tramadol on Intraocular Pressure, Pupil Size and Tear Production in Cats: A Randomized Controlled Trial.”

Dexmedetomidinin Tek Başına ve Tramadol ile Kombine Kullanımının Kedilerde İntraoküler Basınç, Pupilla Çapı ve Gözyaşı Üretimi Üzerine Etkileri: Randomize Kontrollü Bir Çalışma

https://izlik.org/JA34LB45XW

Öz

Bu çalışmanın amacı, intramusküler deksmedetomidinin tek başına veya subkutan tramadol ile kombinasyon halinde uygulanmasının sağlıklı kedilerde intraoküler basınç (İOP), pupilla çapı (PS) ve gözyaşı sekresyonu (TS) üzerindeki etkilerini değerlendirmektir. Otuz sağlıklı kedi (n=30), rastgele iki gruba ayrıldı (n=15/grup). Kedilere ya yalnızca deksmedetomidin (Dex; 25 µg/kg IM) ya da deksmedetomidin + tramadol (Dex-Tra; tramadol 2 mg/kg SC + deksmedetomidin 25 µg/kg IM) uygulandı. İOP, PS ve TS ölçümleri başlangıçta (T0) ve uygulamadan 5, 15 ve 30 dakika sonra (T5, T15, T30) gerçekleştirildi. Dex grubunda, T5-T30 zaman noktalarında İOP, T0’a kıyasla anlamlı olarak azaldı ve PS T5-T15’te artarak T30’da başlangıç değerlerine döndü (p<0.05). Gruplar arası karşılaştırmada, T5’te İOP Dex grubunda Dex-Tra grubuna göre daha düşüktü (p<0.05); T15 ve T30’da gruplar arasında fark gözlenmedi (p>0.05). PS ve TS açısından hiçbir zaman noktasında gruplar arasında anlamlı fark olmadığı görüldü (p>0.05). Her iki protokol de zamanla TS’yi azalttı. Deksmedetomidinin tek başına uygulanması oküler hipotansiyona ve pupilla çapında geçici bir artışa neden olurken, tramadol ile birlikte uygulanması bu etkileri zayıflattı. Her iki rejimin de gözyaşı sekresyonunu azaltması nedeniyle, sedasyon protokolleri seçilirken tonometri, oküler yüzey bütünlüğü ve perioperatif oftalmik yönetim üzerindeki olası etkiler klinisyenler tarafından dikkate alınmalıdır.

Anahtar Kelimeler

Deksmedetomidin , İntraoküler basınç , Kedi , Pupilla çapı , Tramadol

Etik Beyan

Bu çalışma, Atatürk Üniversitesi Hayvan Deneyleri Yerel Etik Kurulu (HADYEK) tarafından 24 Eylül 2025 tarihli, 231 sayılı karar ve 2025/11 oturum numarası ile onaylanmıştır (Resmî yazı no: E-75296309-050.01.04-2500316654, 25.09.2025). Etik kurula sunulan araştırmanın başlığı: “Kedilerde Deksmedetomidinin Tek Başına ve Tramadol ile Kombinasyon Halinde Kullanımının İntraoküler Basınç, Pupilla Çapı ve Gözyaşı Üretimi Üzerine Etkileri: Randomize Kontrollü Bir Çalışma.”

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