Morphine Versus Ketamine as Adjuvants in Paravertebral Blocks
- Conditions
- Pain, NeuropathicMorphineKetaminePain, PostoperativeAnalgesiaPain, AcutePain, Chronic
- Interventions
- Drug: local anesthetic-morphineDrug: local anesthetic-ketamineDrug: local anesthetic
- Registration Number
- NCT04852484
- Lead Sponsor
- Aretaieion University Hospital
- Brief Summary
The aim of this study will be to compare the effects of morphine versus ketamine when they are used as adjuvants to the local anesthetic in paravertebral nerve blocks performed with the aid of ultrasound. Furthermore, a group of local anesthetic without an adjuvant, will also be compared to the two groups
- Detailed Description
Elective thoracotomies are usually performed for removal of pathological masses in the mediastinum, lung parenchyma and upper gastrointestinal system. They are considered to be painful operations, related to both acute and chronic pain (post- thoracotomy pain syndrome), the latter lasting for a minimum period of 2 months.
Post-operative thoracic pain is associated often with diaphragmatic dysfunction, which can also lead to atelectasis and pneumonia and post-operative pulmonary complications in general.
Several techniques have been tried in order to minimize such events. Thoracic epidural analgesia, intravenous analgesia, intercostal blocks, local infiltration of local anesthetics by the surgeon are some of them.
Paravertebral thoracic blocks have become increasingly popular in recent years since they are less likely to cause neurologic complications than thoracic epidural analgesia. Moreover, bleeding disorders, and use of anti-coagulant and anti- thrombotic medications, which are considered as contraindications to an epidural procedure, are not strict contraindications in the performance of paravertebral blocks, especially when they are performed under ultrasonographic guidance.
Ropivacaine and Levobupivacaine are the most popular local anesthetics that have been used. Moreover, several adjuvants have been added to them in order to enhance the effects of those blocks. Dexamethasone, Morphine, Dexmedetomidine, Clonidine, Ketamine, Magnesium Sulphate are some of them. Results are variable.
The rationale behind adjuvants used to enhance effects of local anesthetics is the fact that some seem to act directly in the spinal cord receptors and the central nervous system. The effect of morphine on the dorsal horns of the spinal cord has been extensively studied in the past. Due to its limited lipophilicity, it is assumed that administering the specific drug to the paravertebral space could lead to its transfer and action on the dorsal horns.
On the other hand, the action of ketamine seems to be by blocking N-Methyl-D-Aspartate (NMDA) receptors in the spinal cord. It is also considered to have an effect on voltage sensitive Ca2+ channels, opioid receptors, and monoaminergic receptors. Therefore, it is considered overall to affect nociception.
Overall, it is assumed that morphine might have an effect on the dorsal horns of the spinal cord, and ketamine on NMDA receptors at "higher pain centers". It is also assumed that there will be some degree of systemic absorption due to the rich vascular supply of the specific area. The investigators aim to compare the effects of those two when they are used as adjuvants to the local anesthetic in paravertebral nerve blocks performed with the aid of ultrasound. Furthermore, a group of local anesthetic without an adjuvant, will also be compared.
Recruitment & Eligibility
- Status
- ACTIVE_NOT_RECRUITING
- Sex
- All
- Target Recruitment
- 90
- patients undergoing elective thoracotomy for any cause
- American Society of Anesthesiologists class I-III (ASA I-III)
- known allergy to local anesthetic
- local inflammation
- paravertebral tumor
- severe respiratory distress ( breathing dependence on accessory muscles)
- severe spinal deformities
- severe ipsilateral diaphragmatic paresis
- morbid obesity (BMI>35 kg/m2)
- blood coagulation disorders
- known contraindication for administration of ketamine or morphine
- psychiatric disorders
- severe cardiovascular disease
- systematic use of opioids due to chronic pain
- renal or hepatic failure
- patients who refuse to participate
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description local anesthetic and morphine group local anesthetic-morphine paravertebral block with local anesthetic and morphine, followed by a continuous infusion of local anesthetic and morphine in the paravertebral space local anesthetic and ketamine group local anesthetic-ketamine paravertebral block with local anesthetic and ketamine, followed by a continuous infusion of local anesthetic and ketamine in the paravertebral space local anesthetic group local anesthetic paravertebral block with local anesthetic only, followed by a continuous infusion of local anesthetic only in the paravertebral space
- Primary Outcome Measures
Name Time Method morphine consumption in the first 48 hours 48 hours postoperatively patients will be followed for cumulative morphine consumption through patient-controlled analgesia device for 48 hours postoperatively
- Secondary Outcome Measures
Name Time Method incidence of chronic pain 3 months after surgery 3 months after surgery occurrence of chronic pain at the site of the operation 3 months after surgery, with the use of the Numeric Rating Scale (NRS), at rest and during movement
pain score 12 hours postoperatively 12 hours postoperatively pain score by the use of Numeric Rating Scale (NRS) 12 hours postoperatively, ranging from 0 to 10, where 0 means "no pain" and 10 means "worst pain imaginable"
pain score 48 hours postoperatively 48 hours postoperatively pain score by the use of Numeric Rating Scale (NRS) 48 hours postoperatively, ranging from 0 to 10, where 0 means "no pain" and 10 means "worst pain imaginable"
morphine consumption in the first 6 hours 6 hours postoperatively patients will be followed for cumulative morphine consumption through patient-controlled analgesia device for 6 hours postoperatively
morphine consumption in the first 12 hours 12 hours postoperatively patients will be followed for cumulative morphine consumption through patient-controlled analgesia device for 12 hours postoperatively
side effects postoperatively 96 hours postoperatively patients will be monitored for side-effects of the administered agents postoperatively
satisfaction from postoperative analgesia 48 hours postoperatively satisfaction from postoperative analgesia on a four-point Likert scale with 1 marked as minimal satisfaction and 4 as maximal satisfaction
pain score on arrival to Post-Anesthesia Care Unit (PACU) immediately postoperatively pain score by the use of Numeric Rating Scale (NRS) on arrival to PACU, ranging from 0 to 10, where 0 means "no pain" and 10 means "worst pain imaginable"
morphine requirement during surgery intraoperatively dose of required morphine administered intraoperatively
time to first request for analgesia during stay in Post-Anesthesia Care Unit, 24 hours postoperatively the time for the first patient request for analgesia will be noted
morphine consumption in Post-Anesthesia Care Unit (PACU) 24 hours postoperatively mg of morphine requested during patient PACU stay
pain score 6 hours postoperatively 6 hours postoperatively pain score by the use of Numeric Rating Scale (NRS) 6 hours postoperatively, ranging from 0 to 10, where 0 means "no pain" and 10 means "worst pain imaginable"
pain score 24 hours postoperatively 24 hours postoperatively pain score by the use of Numeric Rating Scale (NRS) 24 hours postoperatively, ranging from 0 to 10, where 0 means "no pain" and 10 means "worst pain imaginable"
morphine consumption in the first 24 hours 24 hours postoperatively patients will be followed for cumulative morphine consumption through patient-controlled analgesia device for 24 hours postoperatively
hospitalization time 7 days postoperatively duration of hospital stay after surgery in days
incidence of chronic pain 6 months after surgery 6 months after surgery occurrence of chronic pain at the site of the operation 6 months after surgery, with the use of the Numeric Rating Scale (NRS), at rest and during movement
Trial Locations
- Locations (2)
Aretaieion University Hospital
🇬🇷Athens, Greece
KAT General Hospital of Athens
🇬🇷Athens, Greece