By Professor of Anaesthesia and Surgical Intensive Care Faculty of - - PowerPoint PPT Presentation

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Professor of Anaesthesia and Surgical Intensive Care Faculty of Medicine Alexandria University Lecturer in Anaethesia and Surgical Intensive Care Faculty of Medicine Alexandria University

• Pain is an unpleasant sensory and emotional experience associated with

actual or potential tissue damage; Pain in the knee joint is the most common complication after tibial nailing. Its occurrence has been reported from 10 to 86% of the cases, particularly in young and active patients.

• It is therefore important to choose an effective analgesic regimen with

minimal side‐effects to allow timely mobility, optimal functional recovery and to decrease postoperative morbidity and mortality.

• Spinal anesthesia is a well-established technique for lower limb surgeries.

It is easy to perform and provides fast onset and effective sensory and motor block.

• The combination of local anaesthetics and opioids for postoperative pain

relief allows reduction in doses of both classes of drugs, as a consequence lessening the likelihood of side effects attributable to each.

• Opioids combine to specific opioid receptors in the nervous system and
• ther tissues. There are three principal types of opioid receptors, μ, κ, and δ.

In addition, there are also three subtypes of μ-receptor: μ1 and μ2, and μ3.

• The pharmacodynamic reaction to an opioid depends on the receptor to

which it binds, its affinity for this receptor, and rather the opioid is an agonist or an antagonist.

• Opioids injected in the subarachnoid space seem to act mainly on

µ receptors in the substantia gelatinosa of the dorsal horn by inhibiting excitatory neuropeptide release from C fibers. The extent of uptake from the cerebrospinal fluid by the dorsal horn is determined mainly by the physicochemical properties of the drug, and in specific, lipid solubility. Lipid-soluble compounds enjoy larger direct diffusion into neural tissue besides greater delivery to the dorsal horn by spinal segmental arteries.

• Nalbuphine is a highly lipid soluble opioid with activity that suggests an

agonist action at the κ opioid receptor and activity as an antagonist at the µ-

• pioid receptor.
• The most frequent side effect in patients treated in clinical studies with

Nalbuphine was sedation (36%), (nausea, vomiting 6%), (dizziness, vertigo 5%), (dry oral mucosa 4%), and (headache 3%). Anaphylactic/anaphylactoid and other serious allergic reactions.

• Fentanyl is a lipophilic μ-receptor agonist exerts its effect by combining

with opioid receptors in the dorsal horn of spinal cord.

• Naloxone, is a pure opioid antagonist. Naloxone is a medication used to

counter the actions of opioid especially in overdose. It will mainly reverse the depression of the CNS, respiratory system, and hypotension.

• the aim of this work was to compare the effect of intrathecal

nalbuphine versus intrathecal fentanyl as adjuvants to bupivacaine, as regards:

• 1ry outcome: the post-operative analgesia.
• 2ry outcomes: the hemodynamic stability, the onset and duration of

sensory/motor block and side effects.

• After approval from the local ethical committee and written informed

consent was obtained.

• This study was carried out in Elhadra University Hospital on fifty patients

aged 20 – 50 years; belonging to American Society of Anaesthesiologists (ASA) physical status I or II, scheduled for internal fixation of tibia of expected duration less than 3 h, under spinal anaesthesia.

• Patients with significant co-existing conditions such as hepatorenal and

cardiovascular diseases.

• Patients with contraindications to regional anesthesia like local infection or

bleeding disorders.

• Patients with allergy to opioids, long-term opioids use, and a history of

chronic pain.

• Patients with extremes in weight or in length.

• Patients received intrathecal injection of 2 ml of 0.5% hyperbaric

bupivacaine plus 1 ml fentanyl (50μg).

• Patients received intrathecal injection of 2 ml of 0.5% hyperbaric

bupivacaine plus 1ml nalbuphine hydrochloride (1.6 mg).

• Medical history and Clinical examination
• Routine laboratory investigations

• Patients were monitored using standard monitoring (pulse oximetry,

electrocardiogram, noninvasive arterial blood pressure monitoring) using a multi channel monitor.

• Before the administration of neuroaxial anaesthesia, 18-gauge intravenous

cannula was inserted and intravenous preload of 10 mL/kg lactated Ringer’s solution was given.

• Patient was placed in the sitting position; At the puncture site, 2 ml of 2%

lidocaine were injected subcutaneously. The puncture was performed at L3- 4 interspace using a 25 gauge spinal needle (Quincke) by midline approach.

• After a successful dural puncture, the anaesthetic solution was injected

according to the group. The patient was then turned supine immediately elevation of the head by a pillow. Oxygen administered through a simple face mask (5 L/ min).

• Patients received intrathecal injection of 2 ml of 0.5% hyperbaric

bupivacaine plus 1 ml fentanyl (50μg).

• Patients received intrathecal injection of 2 ml of 0.5% hyperbaric

bupivacaine plus 1ml nalbuphine hydrochloride (1.6 mg); (20 mg Nalbuphine in 12 ml normal saline 0.9%).

The following parameters were measured for each patient:

• Age (yrs), sex, weight (kg) and Height (cm).
• Non-invasive mean arterial blood pressure (mmHg).
• Heart rate (beats/minute).

These parameters were measured and recorded:

• At 5 minutes before the intrathecal injection.
• At 2, 4, 6, 8, 10, minutes after intrathecal injection and then every 15

minutes till the end of the procedure.

Sensory blockade: was determined by ice cold test to estimate the following:

• Time (in minutes) of the onset of sensory block at T10 dermatome.
• Time (in minutes) for 2 segment regression which was defined as the time it

took for the sensory level to decrease by 2 dermatomal levels measured from the highest obtained sensory level every 15 min.

Motor blockade: was evaluated by the (modified Bromage score):

• Time (in minutes) of onset of motor blockade from the end of intrathecal injection

till the patient reached complete motor blockade (modified Bromage score 3).

• Duration of motor block (in minutes) was recorded from the time at which the

patient reached complete motor blockade (modified Bromage score 3) to the time the patient was able to rise his/her legs in bed against gravity (modified Bromage score 0) every 30 min in the post-operative care unit.

Able to raise straightened legs against resistance, no detectable motor block. Unable to raise straightened legs, but able to flex knees. Unable to flex knees, but able to flex ankle. Unable to move hip, knee or ankle.

• Patients was assessed using Visual analogue scale (VAS), It ranges from 0

indicating no pain till 10 indicating severe intolerable pain with variable degrees of ascending pain in between.

• The duration of analgesia was defined as the period from spinal injection to the

first time when the patient complained of pain in the postoperative period (VAS ≥ 1).

• VAS assessed in the immediate postoperative period, then every 2hours for the

first 8hours, then every 6hours for the rest of the first 24hours.

• The time of the first request analgesia was recorded (VAS ≥ 4) and treated

by intramuscular diclofenac sodium (75mg)

• Total dose of analgesic requirements was calculated and elaborated

statistically.

• Such as, hypotension, bradycardia, respiratory depression, pruritus,

nausea, vomiting and shivering were recorded.

10 20 30 40 50 60 70 Male Female Percentage F N

5 10 15 20 25 30 35 F N Mean of age (years)

20 40 60 80 100 120 140 160 180 F N Mean of height

10 20 30 40 50 60 70 80 F N Mean of weight

10 20 30 40 50 60 F N

Mean of duration of operation (min)

5 min before After 2 min After 4 min After 6 min After 8 min After 10 min After 25 min After 40 min After 55 min 0.0 75 80 85 90 95 100

Heart rate (beats/min) F N

5 min before After 2 min After 4 min After 6 min After 8 min After 10 min After 25 min After 40 min After 55 min 65 70 75 80 85 90

Mean arterial blood pressure (mmHg) F N

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 F N

Mean of time of the onset of sensory block (minutes)

20 40 60 80 100 120 140 F N

Mean of time for two-segment regression (minutes)

1 2 3 4 5 6 F N

Mean of onset of the motor blockade (minutes)

10 20 30 40 50 60 70 80 90 100 F N

Mean of duration of the motor blockade (minutes)

10 20 30 40 50 60 70 80 90 100 F N

Mean of duration of analgesia (minutes)

20 40 60 80 100 120 140 160 180 200 F N

Mean of time for 1st rescue analgesia (minutes)

10 20 30 40 50 60 70 80 90 100 F N

Mean of time for 1st rescue analgesia (minutes)

5 10 15 20 25 30

Hypotension Nausea and vomiting Pruritis Shivering Bradycardia Respiratory depression

Percentage Complications F N

• 1. Spinal analgesia plays an important role providing satisfying opioid free

postoperative analgesia.

• 2. The addition of intrathecal Nalbuphine 1.6 mg to spinal bupivacaine (0.5%

hyperbaric solution) prolonged the onset time of motor blockade and prolonged the duration of analgesia compared with the fentanyl group.

• 3. Intrathecal fentanyl in a dose of 50 μg and Nalbuphine in a dose of 1.6 mg

are safe adjunct to Bupivacaine and have no added side effects to those of

• ther opioids.

From the present study, the following can be concluded:

• 4. Intrathecal fentanyl in a dose of 50 μg and Nalbuphine in a dose of 1.6 mg

have no serious effect on heamodynamics as bradycardia and not cause serious complication as respiratory depression.

• 5. Intrathecal fentanyl and Nalbuphine don't prolong the duration of spinal

motor block and hence don't interfere with postoperative mobilization.

From the present study, the following can be concluded:

• 1. Nalbuphine and fentanyl are good option to be added to intrathecal

Bupivacaine to improve the postoperative analgesia.

• 2. Further studies are recommended to be done for comparing the efficacy of

fentanyl and Nalbuphine when used intrathecally for postoperative analgesia and long term chronic pain syndromes.

From the current study, we recommend that: