Effects of adding trinitroglycerin (TNG) to the patient controlled intravenous analgesia pump in patients with lower limb orthopedic surgery

The aim of current study is to survey effects of adding trinitroglycerin (TNG) to the patient controlled intravenous analgesia pump in patients with lower limb orthopedic surgery

Clinical trial study, with parallel groups, double blinded, randomized

75 patients who undergo surgery due to fracture of the lower limbs in Rasul Akram hospital were selected and were randomly per muted blocks and based on online randomization software, divided into three equal groups and received one of following analgesia methods via intravenous pain pump after the end of surgery in recovery: Control group: Without using Trinitriglycerin (TNG).  First intervention group: Using 500 microgram (mcg) Trinitriglycerin (TNG) in the pain pump. Second intervention group: Using 1000 mcg, TNG in the pain pump.  Pain in patients is measured 4, 8, 12 and 24 hours after surgery by Visual analogue scale.

Inclusion criteria: Lower extremities orthopedic patients, Spinal anesthesia with 15 milligram (mg) bupivacain 0.5%, Patients with American Society of Anesthesiologists (ASA) I,II. Exclusion criteria: Addiction to alcohol, benzodiazepines and opium, Heart failure, Patients dissatisfaction, Allergies to any of used drugs, Seizure, Valvular heart disease, Arrhythmia.

First intervention group: Using 500 microgram (mcg) Trinitriglycerin (TNG) in the pain pump. (Nitral, Caspian Tamin Pharmaceutical Co.) Second intervention group: Using 1000 mcg, TNG in the pain pump. Control group: Pain pump without using TNG in the pain pump

Patient's pain 4, 8, 12 and 24 hours after surgery.

First, individuals who have the characteristics necessary to enter the study are usually taken from a non-random sample using a simple sampling method. Then, randomization is done between study groups. In this study, a block randomization method (including 4 blocks) is used. One of the study partners who has not been blindfolded, named pain pump with and without TNG with the letters A and B. Then, the researcher will distribute A and B packages among patients in a randomized block method (ABAB, BABA, AABB, BBAA, ABBA, BAAB; A, first person; B, Second person; A, third person; B,fourth person B etc.). Then, selecting the blocks are continued until reaching the sample size. Random sequence generation was done using simple randomization. To construct a random sequence to the possible blocks (6 blocks), we give numbers to them from one to six numbers. According to the sample size, each number of 4 blocks required will be used. the number of blocks was chosen from the random numbers table and based on these numbers we identified the sequence of blocks in each group.

In this study blinding will be as follows: Researcher and data collector are the same and are blinded and unaware of the contents of the pain pumps. Patients: Are blinded because they are unaware of the contents of the pain pump. Blinding: Based on the sequence of random numbers, group A or B will be placed inside sealed envelopes. A researcher who does not know the contents and sequence of envelopes will open the envelopes accordingly, and based on the fact that A or B has arrived, they will use a pre-filled pump A or B, respectively. One of the members of the research team has put the A label or label B on the pumps (only the same person is aware of the contents inside the pump)

We have not yet set a conclusion

We have not yet set a conclusion

We have not yet set a conclusion

We have not yet set a conclusion

We have not yet set a conclusion

We have not yet set a conclusion