What Is Procaine?

Procaine is a local anesthetic. Its hydrochloride is commonly used clinically, also known as "nufocaine". White crystal or crystalline powder, easily soluble in water. It is less toxic than cocaine. Adding a small amount of epinephrine to the injection can prolong the action time. Used for infiltration anesthesia, spinal anesthesia, "closed therapy", etc. In addition to the overdose caused by the central nervous system and cardiovascular system reactions, occasional allergic reactions, skin allergy tests should be performed before medication. Its metabolite paraben (PABA) can reduce the antibacterial efficacy of sulfa drugs ^[1] .

Drug Name: Procaine
Alias: "Nufocaine"
Foreign name: Procaine
Main indications: Infiltration anesthesia, spinal anesthesia, "closed therapy"
Adverse reactions: Can cause anxiety, floating, and paresthesia
Dosage form: injection
Athletes use with caution: Use with caution

Whether to include health insurance: Incorporate
Drug type: chemical
Basic meaning: Local anesthetic
Main traits: White crystal or crystalline powder
Precautions: Skin allergy test should be performed before medication
Pharmacology: Less toxic and is one of the commonly used local anesthetics
Mainly involved: Western medicine, injection, medicine, anesthetic

Introduction to Procaine Compounds

Chinese name: Procaine

Chinese alias: procaine hydrochloride; norfocaine; 2-diethylaminoethyl 4-aminobenzoate; 2- (diethylamino) ethyl-4-aminobenzoate; norfcaine Procaine base

English name: procaine

English alias: Benzoic acid, 4-amino-, 2- (diethylamino) ethyl ester; 4-aminobenzoic acid 2-diethylaminoethyl ester; PROCAINE; novocaine

CAS number: 59-46-1

Molecular formula: C ₁₃ H ₂₀ N ₂ O ₂

Molecular weight: 236.31000

Exact mass: 236.15200

PSA: 55.56000

LogP: 2.34860

Regulatory Information

China

Controlled Goods: Narcotic Drugs

Physical and chemical properties

Density: 1.077g / cm ³

Melting point: 61ºC

Boiling point: 373.6ºC at 760 mmHg

Flash point: 179.8ºC

Refractive index: 1.542

Security Information

Packing level: III

Hazard category: 6.1 (b)

Customs Code: 2922499100

Dangerous Goods Transport Code: UN 3249 ^[2]

Properties: The hydrochloride is colorless, odorless, small needle-like or leaflet-like crystals, with a slightly bitter taste, and the tongue tastes dull. Soluble in water, slightly soluble in ethanol, slightly soluble in chloroform. Its aqueous solution is unstable, especially when it encounters light, acid-base substances are easy to deteriorate.

Procaine Drug Description

Pharmacological effects of procaine

Less toxic, it is one of the commonly used local anesthetics. This medicine is a short-acting ester local anesthetic, which has low lipophilicity and weak penetration into mucous membranes. Generally not used for surface anesthesia, local injection is often used for infiltration anesthesia, conduction anesthesia, subarachnoid anesthesia and epidural anesthesia. The effect is 1-3min after injection and can be maintained for 30-45min, and the maintenance time can be extended by 20% after adding adrenaline. Procaine can be hydrolyzed by esterase in plasma and converted into p-aminobenzoic acid (PABA) and diethylaminoethanol. The former can counteract the antibacterial effect of sulfa drugs. Therefore, simultaneous application with sulfa drugs should be avoided. Procaine can also be used for local closure of injury sites. Overuse can cause central nervous system and cardiovascular reactions. It can sometimes cause allergic reactions, so a skin allergy test should be done before medication, but allergic reactions can still occur in people with negative skin tests. Those who are allergic to this medicine can use chloroprocaine and lidocaine instead ^[1] .

Procaine pharmacodynamics

Acting on peripheral nerves, it can stop and block the generation and transmission of nerve impulses, stabilize the membrane surface of neural tissue, reduce the permeation of Na +, block normal polarization and depolarization alternately, and impel the transmission of nerve impulses. , Clinically called conduction block.

Act on the central nervous system, generally excite first and then suppress normal activities. The effect is related to blood concentration, which is a precursor of poisoning reaction.

It acts on the cardiovascular system. A single intravenous injection followed by a intravenous drip can restore the normal heartbeat to a normal speed and is often used for rescue.

Local anesthetic

Appropriate epinephrine is usually added to the solution, usually 5 g / ml. The nerve block can be doubled. The subarachnoid block is limited to 100 g / ml. The purpose is to shrink local blood vessels, reduce blood flow, slow down the absorption of local anesthetic drugs, prolong the duration of action, and infiltrate the surgical area accordingly. Reduced blood. In addition, clinically, a combination of a drug with a rapid onset of action and a short duration and a slow onset and a long duration are formulated into a local anesthetic mixture (such as 1.6% lidocaine ten 0.2% tetracaine or 1% lidocaine ten 0.2 The mixed solution of% tetracaine is used for epidural block), which complement each other and is widely used, but special attention should be paid to the addition of the two toxicity ^[1] .

Procaine pharmacokinetics

Absorption: Except for topical local anesthesia, no matter which way to administer, the absorption is complete, the blood-rich area is faster, and it enters the heart immediately after intravenous injection, and the drug can be discharged from the venous plexus during epidural block Odd veins should enter the heart with caution.

Metabolism: Local anesthetics are divided into two groups: esters and amides according to their chemical structure. Most of the esters are hydrolyzed and converted by plasma cholinesterase, and most of the amides are metabolized by liver.

The onset time is generally 5 to 15 minutes, which varies with each drug. Usually, the local anesthetic pKa determines the onset of the drug. The closer the pKa is to physiological pH (7.4), the faster the onset. Intravenous injection and tracheobronchial spray are 1-3 minutes.

The peak value and duration of action of blood drugs vary according to the inconsistency of absorption, metabolism, and distribution in the body; how much the combination of local anesthetic and protein significantly affects the local anesthetic aging, but does not affect the onset speed and strength of the drug.

Excretion: The general metabolites are excreted by the kidney, but the original drug can be excreted in the urine, 2% procaine, 6% bupivacaine, 10% lidocaine, 1% etidocaine Mepivacaine is as high as 16%, and only a small amount appears in feces due to incomplete intestinal absorption after entering bile ^[1] .

Procaine indications

1. Mainly used for infiltration anesthesia.

2. For lower abdomen surgery that does not take long. Can also be used for local intravenous anesthesia of the limbs.

Procaine

3. Used in "closed therapy" to treat certain injuries and inflammation, which can alleviate the symptoms of injury and inflammation.

4. Used to correct vasomotor dysfunction of the limbs.

5. Treatment of neurosis.

Procaine dosage usage

Local injection: The injection concentration is mostly 0.25% -0.5%, the dosage depends on the needs of the disease, but it cannot exceed 1.5g per hour. Its short anesthesia time can add a small amount of epinephrine (1; 1) to extend the duration of the effect. Dental anesthesia is sometimes used at 2% to 4% solution concentrations.

Procaine precautions

1. Misinjection into blood vessels at high concentrations can cause anxiety, floating, dizziness, unconsciousness, paresthesia, tinnitus, and facial and distal limb tremors; subsequently, tense clonic seizures may occur. When plasma levels are high, breathing can be suppressed

coma. 2. Excessive dosage may cause nausea, sweating, pulse rate, dyspnea, facial flushing, delirium, excitement, and convulsions. For convulsions, intravenous injection of isoprenebital can be used to rescue.

3. During spinal anesthesia, blood pressure often drops, and 15 to 20 mg of ephedrine can be injected intramuscularly before anesthesia to prevent it.

4. Sometimes anaphylactic shock occurs, so the patient's allergic history should be asked before medication, and patients with allergic constitution should be tested intradermally (intradermal injection of 0.25% solution 0.1ml).

5. Should not be compatible with glucose solution, because it can reduce its local anesthetic effect.

Clinical application of procaine

Procaine is not only a local anesthetic drug, but also widely used in the treatment of many diseases in clinical departments.

Clinical application in pediatrics

Treating whooping cough

Procaine vein closure therapy has the ability to block or reduce the afferent impulse of bronchial mucosal stimulation, block the strong stimulus from transmitting to the medullary to the cerebral cortex, reduce spasm, and at the same time have a spasmolytic effect on the bronchial smooth muscles, which is good for secretion To reduce the cough and prevent suffocation. Chen Wenqing reported that 50 cases of infantile pertussis were randomly divided into two groups, 30 cases in the treatment group and 20 cases in the control group. The children in both groups were treated symptomatically with anti-inflammatory, oxygen inhalation, and ultrasonic nebulization. The treatment group was given procaine 5 8mg / kg added 5% glucose solution intravenously; the control group used aminophylline 2 4mg / kg added 5% glucose solution intravenously. The treatment group showed significant effect.

27 cases, 2 cases were effective, with a total effective rate of 96.67%; 5 cases were significantly effective in the control group, 5 cases were effective, and the total effective rate was 50%. Efficient and safe medicine. Treating infantile asthmatic pneumonia

Procaine has the effect of relaxing smooth muscles, which can dilate the bronchi, reduce mucosal edema, reduce secretions and make the secretions dilute and discharge easily, thereby improving the ventilation function. Chen Fujian et al reported that 85 infants with asthmatic pneumonia were divided into two groups, 45 in the treatment group and 40 in the control group. The treatment group was given procaine + danshen injection at the same time as the comprehensive treatment, and the control group was treated with asthma such as hormone + aminophylline. Results: There were 16 cases in the treatment group, 26 cases were effective, and the total effective rate was 93.4%; 6 cases were in the control group, 23 cases were effective, and the total effective rate was 72.5%. Compared with the total effective rate, the difference between the two groups was significant (P <0.05, P <0.01). Conclusion: Procaine + Danshen injection has a significant effect on infantile asthmatic pneumonia, and the drug source is sufficient. Convenient source and low price.

Clinical application in dermatology

Treating shingles

Shingles virus lurks in the neurons of the sensory ganglia. When the body's immune function is low, the virus is activated and herpes develops along the peripheral nerve fibers to the skin in this area. Procaine can block the centripetal conduction of malignant stimuli at the lesion and promote metabolism at the lesion. Hu Haibin reports: 76 patients with shingles were given 2% procaine, vitamin B1, and polymyocytes in a ratio of 2: 1: 1, and were locally closed. Results: On the third day, the affected area had no sensation of burning and pain There were 41 cases of herpes in the herpes department, and there was no obvious improvement in the affected area, and the closure was repeated once more. On the fifth day, the affected area had no burning or pain, and 35 cases in herpes department. All work.

Treatment of allergic purpura

Henoch-Schonlein purpura is a kind of capillary allergic disease that is based on a wide range of small vessel inflammation. Procaine is diluted to about 0.05% and slowly intravenously at a low concentration. Effect, alleviate the symptoms of vascular inflammation injury site. Wu Jiaming reported: 68 cases of allergic purpura patients, all patients were given intravenous procaine 8-12mg / (kg · d), and slowly dripped in 500ml glucose solution, the total course of treatment was 13-15 days. Results: All cases Purpura gradually subsided, abdominal pain and arthralgia disappeared, 64 patients had normal urine tests, and the cure rate was 94%. No adverse reactions occurred.

Treatment of pruritus

Procaine can block nerve conduction and reduce or eliminate itching in patients; inhibit platelet aggregation and improve local blood circulation; regulate cell metabolism to prevent abnormal skin proliferation. Dong Fangping reported: 84 patients with proliferative pruritic skin disease were given procaine 68mg / kg, vitamin C 3.0g, and 500ml glucose solution slowly and intravenously for 14 days as a course of treatment, with 1 to 2 courses of medication. Results: 13 cases were cured, 34 cases were markedly effective, 29 cases were effective, and 8 cases were ineffective. The total effective rate was 90.47%. Jia Limei and other reports: 56 elderly patients with refractory pruritus were given 2% procaine 10-30ml and 5% glucose 500ml slowly intravenously, once per day, 10 days as a course of treatment, after 3 to 5 courses Treatment results: 29 cases were cured, 14 cases were markedly effective, 8 cases were effective, and 5 cases were ineffective. The total effective rate was 91.07%.

Neurodermatitis

Neurodermatitis is a neurological dysfunction skin disease, characterized by severe itching and localized lichenification of the skin. Procaine blocking therapy can block malignant stimuli, protect the nervous system, and restore normal function. Zhou Jie and other reports: 106 patients with primary neurodermatitis were treated with 520-600 mg of procaine hydrochloride and 300 mg of vitamin C by intravenous drip in 5% glucose solution once a day for 15-20 days as a course of treatment. . Results: Except for one patient who switched to other treatments due to adverse reactions to the first medication, the remaining 23 patients were cured after 1 course of treatment, 64 patients received 2 courses, and 18 patients were discharged after 3 courses.

Clinical application in obstetrics and gynecology

Treatment of cervical dystocia

Procaine has a significant effect on cervical dystocia by cervical injection. The method is simple, easy, effective, and worthy of promotion. It increases the vaginal delivery rate and reduces the cesarean delivery rate. Yue Jinhua and other reports: 64 cases of cervical dystocia, including 55 cases of cervical edema, 9 cases of hard cervical cervix, slow injection of 1% procaine 3ml at three points of cervical edema, results: 43 of 49 cases of cervical edema (87.8%) Cervical edema disappeared within 40 minutes after injection. Six cases of cervical edema disappeared after injection, but the delivery was terminated by cesarean section due to abnormal fetal position and other reasons.

Treatment of cervical edema

Procaine is absorbed through the mucous membranes to numb nerve endings, relieve muscle tension, relax cervical tissue, and promote the development of the labor process. Yu Chunxia et al. Reported that 30 cases of cervical edema patients were treated with 1% procaine-dipped gauze during the delivery process. Results: Cervical edema basically disappeared after 30 minutes of wet application. At the same time, maternal pain was significantly reduced and tension was relieved. The good effect can promote the progress of the labor process, without any impact on the mother and the fetus.

Oxytocin

Procaine anesthesia combined with atropine relaxes the cervical ring muscles. It is used as a cervical injection during labor, which can achieve the effects of oxytocin, significantly shorten the labor and analgesia. Ju Yanmei reported that 128 cases of active women during labor were treated with atropine. 0.5mg, 2% procaine 5ml plus normal saline 10ml was injected at 3, 9 or just 12 o'clock in the cervix. Results: The average delivery time, the rate of dilation of the uterine cavity, and the time from delivery to delivery were better than those of the control group (P <0.01). The difference was very significant, and the clinical effect was indeed satisfactory.

Clinical Application in Gastroenterology (Treatment of Pancreatitis)

Procaine is a calcium non-selective inhibitor that can inhibit the hyperpolarization of microcirculation endothelial cells, protect the stability of cell membranes, and increase the release of prostacyclin and intracellular adhesion molecule-1 to protect the microcirculation. At the same time, it can increase the return of lymphatic fluid in the abdominal cavity and reduce the edema caused by inflammation, so as to improve the microcirculation of internal organs. Reported by Xiao Chunming, etc .; 40 patients with severe acute pancreatitis were divided into 23 cases in the procaine treatment group and 17 cases in the non-procaine treatment group. The two groups routinely maintained the patient's internal environment as the main measure: including In addition to the same treatments, a large number of fluid supplements, correction of water, electrolyte and acid-base imbalances, appropriate application of fresh plasma and albumin to increase plasma colloid osmotic pressure, application of anti-pancreatic enzymes and drugs to reduce pancreatic secretion, anti-infective treatment, etc. 100% intravenous infusion of 1% procaine for 24 h to improve pancreatic microcirculation. Results: 20 cases were cured in the procaine treatment group, 3 died, and the mortality was 13.0%; 9 cases were cured in the non-procaine treatment group, 8 died, and the mortality was 47.1%, and the procaine treatment group died. The rate was significantly lower than that in the non-procaine treatment group (P <0.05). Conclusion: The effect of the procaine treatment group in severe acute pancreatitis is better than that of the non-procaine treatment group, and it is worth promoting. Zhang Guifang reports: 100 patients with pancreatitis were randomly divided into two groups of 50 patients. The treatment method was based on the application of antibiotics. The treatment group was given 1.0 g of procaine and 500 ml of 5% glucose, intravenously, once a day. The control group was given 654-2 10 mg intramuscularly, 3 times a day. 3 5 days is a course of treatment. Results For acute pancreatitis, 85% of the treatment group had significant relief of abdominal pain in 2 to 3 days. At this time, the symptoms did not repeat after stopping the drug, while 60% of the control group relieved of abdominal pain in about 2 to 3 days. Immediately after taking the medicine for 3 days, 654-2 10mg is reduced daily. When it is reduced to 10mg / d, it needs to be maintained for 3 to 5 days according to the condition, and the course of treatment needs more than 1 week. Otherwise, abdominal pain will easily recur. For chronic pancreatitis, the abdominal pain disappeared in the treatment group after 1 week of medication, and the abdominal pain disappeared in the control group after 10 days of continuous medication. Conclusion: Procaine has a good effect on acute edema pancreatitis, acute recurrent pancreatitis, chronic recurrent pancreatitis, and acute pancreatitis.

Clinical Application in Respiratory Medicine

Treatment of hemoptysis

Intravenous infusion of procaine can expand peripheral blood vessels and reduce the amount of blood returned to the heart. Pulmonary tuberculosis patients with hemoptysis, by dilating the capillaries of the lungs, reduce the resistance of the pulmonary circulation, thereby reducing the pulmonary arterial pressure, reducing the pulmonary blood flow and achieving hemostasis. Li Furong et al reported that 16 patients with massive hemoptysis of pulmonary tuberculosis were treated. Methods: Procaine was formulated into a 0.25% solution of 200ml, once a day, with a drip rate of 20 to 40 drops / min, until the hemoptysis stopped. Results: Of the 16 patients in this group, 12 were significantly effective, 3 were effective, and 1 was ineffective (6.2%). The total effective rate was 93.8%.

Procaine can produce a kind of continuous benign stimulation to acupoints by acupoint injection, maintain a certain "needle feeling" within 24 hours, and produce a moderate "vasoconstriction state" to achieve the purpose of hemostasis. Liping Liu reports: 52 patients with hemoptysis of lung disease, 2% procaine injection 4ml. Take bilateral Neiguan acupoints and inject 1.5 2m1 each time, once a day. Results: 29 cases were markedly effective, 15 cases were effective, the total effective rate was 84.6%, 8 cases were ineffective, accounting for 15.33%.

Procaine poisoning

Procaine has poor permeability to the skin and mucous membranes and is mainly used for infiltration anesthesia. Also used as spinal anesthesia, regional block and peripheral plexus block. The drug is low in fat solubility, the plasma protein binding rate is 5%, the half-life of adults is 30-50 minutes; children is 54-114 minutes. Quick onset and short duration of effect. Excessive dose of this drug first stimulates the nervous system and then suppresses it. The maximum dose per adult is 600 mg.

Clinical manifestation

1. Excessive amount or rapid injection of concentrated solution into the blood vessels can cause nausea, sweating, increased pulse, dyspnea, facial flushing, delirium, excitement, convulsions, until coma and respiratory paralysis. Spinal anesthesia often drops in blood pressure.

2. Allergic skin reactions: erythema, pruritus, rash, urticaria, edema, occasionally cardiovascular shock or collapse.

3. Cardiovascular inhibition: weakened myocardial contractility, slowed heart rate, decreased blood pressure, conduction block, arrhythmia, and cardiac arrest.

4. Methaemoglobinemia: It can cause this disease at normal therapeutic doses, and symptoms of hypoxia and cyanosis occur.

5. Malignant hyperthermia: It has been reported to cause this disease after application of this drug, manifested as muscle twitching, rigidity, excessive ventilation and tachycardia.

diagnosis

The main points of procaine poisoning diagnosis are:

With the history of procaine medication, the above manifestations appear.

treatment

The main points of treatment for procaine poisoning are:

1. Before applying this medicine, a skin allergy test should be done. When an allergic reaction occurs, discontinue the drug immediately, and symptomatic and supportive treatment.

2. Patients with convulsions can be rescued by intravenous injection of isoprene barbitur.

3. Before spinal anesthesia, intramuscular injection of 15-20 mg of ephedrine can prevent blood pressure drop that often occurs in spinal anesthesia.

4. When the blood methemoglobin concentration exceeds 30%, methylene blue 1 to 2 mg / kg can be injected intravenously and oxygen can be used for treatment.

5. Treatment of malignant hyperthermia: rapid intravenous injection of 1 to 2 mg of triptanil, which can be repeated every 5 to 10 minutes when necessary until the total amount reaches 10 mg / kg. Satisfactory results are often achieved at doses of 2 to 5 mg. Oral relapse prevention was performed at a dose of 1 to 2 mg / kg, with a maximum dose of 100 mg, 4 / d for 2 to 3 days ^[3] .