Intraoperative Lidocaine Infusion as a Sole Analgesic Versus Morphine in Laparoscopic Gastric Bypass Surgery

Intraoperative Lidocaine Infusion as a Sole Analgesic Versus Morphine in Laparoscopic Gastric Bypass Surgery

Intraoperative Lidocaine Infusion as a Sole Analgesic Versus Morphine in Laparoscopic Gastric Bypass Surgery

Postoperative opioid-centric pain management strategies in obese patients are accompanied by the possible development of; opioid-induced ventilatory impairment (OIVI) and hypoxemia. This presents as sedation and respiratory depression, combined with upper airway obstruction and hypercapnia. If it remains undetected and untreated, it can result in increased perioperative morbidity and mortality.Thus, an increased interest in the use of non-opioid analgesic adjuncts has been prompted. Intra-operative intravenous lidocaine infusion has analgesic, anti-inflammatory, anti-hyperalgesic, opioid-sparing effects with an enhanced recovery after surgery (ERAS) profile. Its postoperative analgesia may last after reduction of its plasma concentration. So, lidocaine could be a good alternative in bariatric surgery. Lidocaine has been studied as part of an opioid-free multimodal analgesia in morbidly obese patients. Also, its use in bariatric surgery showed a decrease in postoperative opioid use and improvement in the quality of recovery.

compare the postoperative analgesic effect of intraoperative lidocaine infusion (Study group) used as a sole analgesic agent, to the intraoperative intravenous morphine (Control group) in laparoscopic gastric bypass surgery.

At induction of anesthesia, patients will receive a loading dose of intravenous (IV) 1.5mg/kg lidocaine hydrochloride 2% slowly over 3 min followed by IV infusion of 2mg/kg/hr lidocaine hydrochloride 2% via infusion pump. The infusion will be continued till the end of surgery.

At induction of anesthesia, patients will receive a loading dose of IV 0.1mg/kg morphine sulphate slowly over 3 minutes followed by IV infusion of normal saline via infusion pump. The infusion will be continued till the end of surgery

At induction of anesthesia, patients will receive a loading dose of 1.5mg/kg lidocaine hydrochloride 2% slowly over 3 min followed by IV infusion of 2mg/kg/hr lidocaine hydrochloride 2% till the end of surgery

At induction of anesthesia, patients will receive a loading dose of IV 0.1mg/kg morphine sulphate slowly over 3 minutes followed by IV infusion of normal saline via infusion pump. The infusion will be continued till the end of surgery

Intensity of pain will be monitored ; on arrival to the PACU, at 20, 40 and 60 minutes after arrival to the PACU by the Numeric Pain Rating Scale. The Numeric Pain Rating Scale (NPRS) is a segmented numeric version of the visual analog scale (VAS) in which the patient selects a whole number (0-10 integers) that best reflects the intensity of pain felt.Where 0 is no pain felt and 10 is the worst pain.

mean values of MBP will be recorded as base line value, before induction of anesthesia, 5 minutes after endotracheal intubation, before pneumoperitoneum, after release of pneumoperitoneum and 10 min after extubation in the PACU

score from 0 to 10. Higher score means patient is fit to transfer to the ward. In the PACU, patients with score ≥ 9 will be transferred to the surgical unit

mean values of HR will be recorded as base line value, before induction of anesthesia, 5 minutes after endotracheal intubation, before pneumoperitoneum, after release of pneumoperitoneum and 10 min after extubation in the PACU

Inclusion Criteria: ASA physical status I- II body mass index (BMI) ˃ 35 scheduled to undergo laparoscopic gastric bypass Exclusion Criteria: Patients' refusal hypersensitivity to the study medications patients with known history of; hepatic disease, renal dysfunction severe renal impairment (eGFR <30ml/min/1.73m2) heart failure; left ventricular ejection fraction than 35% any cardiac dysrhythmias; Adam-Stokes syndrome; Wolff- Parkinson-White syndrome, atrio-ventricular block with heart rate below 50 bpm chronic pain concomitantly taking beta blocking drugs •substance abuse disorder chronic opioid use.