Fentanyl vs Dexmedetomidine for Arthriscopic Shoulder Intervention in Elderly.

Arthroscopic shoulder surgeries are commonly used as a minimally invasive surgery for shoulder diseases. however, it causes moderate-to-severe pain and needs stabilization of hemodynamics, without compromising the patient, to the degree that lessens the intraarticular bleeding to provide adequate visualization by the surgeon owing to inability to use a tourniquet in this situation.

Controlling the pain in shoulder surgery facilitates early mobilization, fast functional recovery and allows pain-free muscle contraction.

Opioids have known side effects, like respiratory depression, postoperative nausea and vomiting, pruritus, difficulty in voiding, and ileus. These complications may lead to a prolonged hospital stay.

The elderly patients are predisposed to a greater hemodynamic changes due to the higher resting sympathetic tone ,altered beta receptor sensitivity , depleted intravascular volume because of frequent use of diuretics, increased myocardial stiffness ,increased arterial stiffness, reduced sinus node function and baroreceptor responsiveness and other patients comorbidities. So they are at increased risk complications as myocardial infarction, stroke and delirium.

Opioid free anesthesia is a technique with no opioids administered intraoperatively through either systemic, neuraxial, or tissue infiltration routes. The number of case reports and small prospective studies from all over the world supports its benefits.

Initially, OFA depends on combinations of non-opioid agents and adjuncts, including lidocaine, magnesium, dexmedetomidine, ketamine,and dexamethasone to produce anesthesia, and analgesia.

Magnesium is a non-competitive antagonist of N-methyl-D-aspartate (NMDA) and has anti-inflammatory effects because it decreases interleukin 6 (IL-6) and tumour necrosis factor (TNF-alpha) levels postoperatively.

Dexamethasone is a mineraloglucocorticoid that has been shown to be effective as an antiemetic in a number of surgical operations. Dexamethasone was integrated into the multimodal opioid-free approach based on De Oliveira's and others' findings that dosages of> 0.1 mg/kg exhibit clinically significant analgesic characteristics in lean adults.

Ketamine is another non-competitive antagonist of the n-methyl-D-aspartate receptor and is commonly used either as a small bolus of 0.25-0.5 mg/kg IBW or in a low-dose continuous infusion at 2-2.5 μg/kg/min. Schug and others have summarised its benefits in APMSE4 in both the general acute pain population and bariatric patients.

Dexmedetomidine is an a2 agonist that possesses anxiolytic, anesthetic, hypnotic, and analgesic properties. In addition, it reduces the pressor responses mediated by the sympathetic nervous system.

Lignocaine is a short-acting amide local anaesthetic agent. It is potent as a sodium channel blocker and has been shown to provide excellent analgesia when administered intravenously . The evidence base supports lignocaine as an analgesic agent, an opioid-sparing agent, an anti-inflammatory and a co-anaesthetic.

n ,Complex regional pain syndrome ,opioid-tolerant patient and early recovery after surgery , however, few studies focused on its ability to improve the surgical field condition which depends on the hemodynamics especially in elderly patients.

Aim of the work is to Compare OFA with Opioid anesthesia (OA) as regards improvement of the surgical field condition in elderly patients undergoing arthroscopic shoulder surgery under general anesthesia.

Hypothesis :

The hemodynamics of the opioid free regimen will provide a better surgical field condition.

Inclusion criteria

• ASA I or II
• aged > 65 years
• undergoing arthroscopic shoulder surgery under general anesthesia.

Exclusion criteria

• uncontrolled systemic diseases
• significant organ dysfunctions
• morbid obesity (BMI >35)
• history of allergy to the study drugs
• use of beta blockers
• chronic use of opioids