Different Modalities of Analgesia in Open Heart Surgeries in Mansoura University

Different Modalities of Analgesia in Open Heart Surgeries in Mansoura University: Randomized Prospective Comparative Study

Cardiac surgery is associated with post-operative pain which is one of the major problems and remains one of the most controversial issues. Inadequate pain control after cardiac surgery increases the incidence of development of many complications. Intravenous opioids are commonly used for postoperative analgesia either on demand "physician or nurse-controlled" or patient -controlled. Multimodal opioid sparing analgesia has become frequently used, These techniques can be achieved with Dexmedetomidine, low-dose ketamine and magnesium. The study hypotheses that control of perioperative quality of pain with opioid sparing medications may improve analgesia and patient outcome.

Pain after cardiac surgery is triggered by numerous factors including skin incision, sternotomy, sternal and rib retraction, internal mammary artery and saphenous vein harvesting, surgical manipulation of pleura, placement of chest tubes and tissue trauma during surgery.Median sternotomy significantly reduces postoperative pulmonary function; however, it is the most commonly used approach because it facilitates exposure of the surgical field. Pain prevents early mobilization, reduction in pulmonary function and accumulation of bronchial secretions resulting in atelectasis, pulmonary infections, hypoxia and increase duration of ICU stay.Prolonged ICU stay is associated with greater risk of respiratory and renal dysfunction, and increases morbidity and mortality. Optimal post-operative pain management allows early weaning from mechanical ventilation and extubation, early mobilization, facilitate beginning of chest physiotherapy, shortens the length of ICU stay and hospitalization, medical costs and decreases incidence of post-operative complications. Opioid infusions and patient-controlled analgesia (PCA) remain the principal and most commonly used for immediate postoperative analgesia after cardiac surgery in Intensive Care Units. Multimodal opioid sparing analgesia has become frequently used. They are used for the opioids sparing effect and for achievement of a more efficient pain management via both central and peripheral anti-nociceptive mechanisms. Dexmedetomidine is an intravenous α-2 agonist widely used for sedation, anxiolysis and for augmenting anesthesia and analgesia with reduction in opioid requirements. Ketamine have a great analgesic effect and can be added to multimodal regimen. Magnesium can be added to multimodal regimen as it acts as a non-competitive antagonist of N-methyl-D-aspartate (NMDA) receptors and has anti-inflammatory effects and can be used in acute pain management. The aim of this study is to compare between traditional high opioid, low opioid and non-opioid technique on the patient outcome. This prospective randomized comparative study will be conducted on 75 patients undergoing cardiac procedures that will require cardiopulmonary bypass and median sternotomy at Cardiothoracic Surgical Department, Mansoura University Hospitals over 24 months. Eligible 90 patients will be randomly allocated to one of three equal groups each contains 25 patients, they will be randomized according to computer-generated randomization sequence: Either high opioid group (group I), Low opioid group (group II) and non-opioid group (group III).

The study subjects will be blinded to the allocated groups. The outcome assessor (the investigator who will assess the primary and secondary outcomes) will be blinded to the allocated groups.

-The patients will receive fentanyl infusion at a rate of 1 µg/kg/h and fentanyl bolus 20-40 µg according to patient hemodynamics. (tachycardia: increase of heart rate >20% of baseline or hypertension: increase of mean blood pressure >20% of baseline).

The patients will receive fentanyl bolus 20 µg/hr and propofol 20 mg at the time of surgical stimulation and according to patient hemodynamics (repeated as required).

The patients will receive infusions of dexmedetomidine 0.2 µg/kg/h, ketamine 2 µg/kg/min, and magnesium sulfate 5 mg/kg/h.

Induction of anesthesia : Midazolam 2 mg, Fentanyl 3 µg/kg, propofol 50-100 mg and Atracurium 0.5 mg/kg. Maintenance of anesthesia (intraoperative until tracheal extubation): Maintenance will be achieved by isoflurane with concentration 0.5-1.5 % with 40% oxygen. During cardiopulmonary bypass by continuous infusion of Propofol at a rate of 2 mg/kg/hr. and Atracurium at a rate of 10 g/kg/min. The patients will receive fentanyl infusion at a rate of 1 µg/kg/h and fentanyl bolus 20-40 µg according to patient hemodynamics. (tachycardia: increase of heart rate >20% of baseline or hypertension: increase of blood pressure >20% of baseline). After tracheal extubation: all the patients will receive standard analgesia (i.v. paracetamol 1 gm every 12 hours and i.v. ketorolac 30 mg every 12 hours) and morphine patient controlled analgesia with bolus dose = 2 mg, lockout interval = 10 minutes, 4-hour dose limit = 10 mg, with no background infusion.

Induction of anesthesia : Midazolam 2 mg, Fentanyl 3 µg/kg, propofol 50-100 mg and Atracurium 0.5 mg/kg. Maintenance of anesthesia (intraoperative until tracheal extubation): Maintenance of anesthesia will be achieved by isoflurane with concentration 0.5-1.5 % with 40% oxugen. During cardiopulmonary bypass by continuous infusion of Propofol at a rate of 2 mg/kg/hr. and Atracurium at a rate of 10 g/kg/min. The patients will receive fentanyl bolus 20 µg/hr and propofol 20 mg at the time of surgical stimulation and according to patient hemodynamics (repeated as required). After tracheal extubation: all the patients will receive standard analgesia (i.v. paracetamol 1 gm every 12 hours and i.v. ketorolac 30 mg every 12 hours) and morphine patient controlled analgesia with bolus dose = 2 mg, lockout interval = 10 minutes, 4-hour dose limit = 10 mg, with no background infusion.

Induction of anesthesia : Midazolam 2 mg, Fentanyl 3 µg/kg, propofol 50-100 mg and Atracurium 0.5 mg/kg. Maintenance of anesthesia (intraoperative until tracheal extubation): Maintenance of anesthesia will be achieved by isoflurane with concentration 0.5-1.5 % with 40% oxygen. During cardiopulmonary bypass by continuous infusion of Propofol at a rate of 2 mg/kg/hr. and Atracurium at a rate of 10 g/kg/min. The patients will receive infusions of dexmedetomidine 0.2 µg/kg/h, ketamine 2 µg/kg/min, and magnesium sulfate 5 mg/kg/h. After tracheal extubation: all the patients will receive standard analgesia (i.v. paracetamol 1 gm every 12 hours and i.v. ketorolac 30 mg every 12 hours) and morphine patient controlled analgesia with bolus dose = 2 mg, lockout interval = 10 minutes, 4-hour dose limit = 10 mg, with no background infusion.

visual analogue scale is a straight horizontal line of fixed length, usually 100 mm. orientated from the left (worst) to the right (best) (where 0 is no pain and 100 is the worst pain) lower score means better outcome

visual analogue scale is a straight horizontal line of fixed length, usually 100 mm. orientated from the left (worst) to the right (best) (where 0 is no pain and 100 is the worst pain) lower score means better outcome

Ramsay sedation score used to assess level of sedation range from 1 to 6 where (1: awake, anxious, agitated, restless, 2: awake, cooperative, orientated, and tranquil, 3: responsive to commands only, 4: asleep, brisk response to light glabellar tap or loud auditory stimulus, 5: asleep, sluggish response to light glabellar tap or loud auditory stimulus and, 6: no response to light glabellar tap or loud auditory stimulus). lower score means better outcome

every 15 minutes in the first hour then every 30 minutes intraoperative and then 1 hour post-operative

every 15 minutes in the first hour then every 30 minutes intraoperative and then 1 hour post-operative

every 15 minutes in the first hour then every 30 minutes intraoperative and then 1 hour post-operative

every 15 minutes in the first hour then every 30 minutes intraoperative and then 1 hour post-operative

Inclusion Criteria: Adult patients of both gender, Aged above 18 years American Society of Anesthesiologists (ASA) physical status II & III, Body mass index less than 40 kg/m2 Scheduled for any cardiac procedure with median sternotomy that require cardiopulmonary bypass at Cardiothoracic Surgical Department, Mansoura University Hospitals. Exclusion Criteria: Patients with pulmonary dysfunction or chronic obstructive pulmonary diseases Acute or unstable angina Previous cardio-thoracic surgery Emergency surgery Left ventricular ejection fraction less than 40% Dysrhythmia or pacemaker Major hepatic or renal dysfunction Need for re-exploration, uncontrolled diabetes (HbA1c > 8.5) Neurological deficit Hyper-magnesemia