Effect of Infusion of Lidocaine, Magnesium and Remifentanil Perioperatively in Patients Undergoing Mastectomy
Condition: Postoperative Pain
MeSH terms: Pain, Postoperative
Study type: Interventional
Phase: Phase 4

Summary: 
      This study aims to compare the quality of perioperative analgesia of lidocaine, magnesium
      sulphate and remifentanil in patients undergoing mastectomy
    

Detailed description: 
      The opioid analgesics are commonly used in clinical practice for pain management in the
      perioperative period. However, many side effects are associated with its use, such as
      respiratory depression, nausea, vomiting, drowsiness, itching, urinary retention,
      constipation, hyperalgesia and impaired immune function. Therefore, alternative techniques
      and drugs have been used to replace their use. One is the intravenous infusion of lidocaine,
      a local anesthetic widely used in anesthetic practice. Another is intravenous infusion of
      magnesium sulphate, a bivalent salt used as a central nervous system depressor, reducing
      intracranial hypertension, in the treatment of epilepsy; eclampsia; in chronic alcoholism; in
      hyaline membranes, such as hyperosmotic diuretic; in malnutrition; hypomagnesaemia; in
      thrombotic microangiopathy; in sickle cell anemia, uterine tetany and atypical ventricular
      tachycardia. Studies show that the use alone or combined of lidocaine and magnesium sulphate
      during surgery significantly decreased postoperative pain. The mechanisms of analgesia this
      local anesthetic in surgical trauma may be blocking neuronal transmission in the lesion site
      alleviating neurogenic response, and anti-inflammatory systemic intrinsic activity.
      Intraoperative lidocaine promotes, besides analgesia, decreased consumption of both
      inhalational anesthetic and opioids; faster return of bowel movements; decreasing the
      production of interleukins and reduction of airway reactivity. This anesthetic also has
      significant anti-inflammatory properties, reduces cytokine release both in vitro and in vivo
      by inhibiting neutrophil activation. N-methyl-D-aspartate (NMDA) receptors are critically
      involved in the induction and maintenance of neuronal hyperexcitability after traumatic
      events, therefore, the use of NMDA antagonists before the incision reduces the excitability
      of the central nervous system and its result is the reduction of clinical hyperalgesia.
      Magnesium sulphate is an antagonist of glutamate NMDA receptor, which gives analgesic,
      anticonvulsant and sedative. It acts as a natural physiological calcium antagonist regulating
      access to the intracellular space. Shows the effect of muscle relaxation by inhibiting the
      release of acetylcholine at the neuromuscular junction, thereby hypermagnesaemia decreases
      sensitivity to acetylcholine of the endplate and the potential amplitude endplate. Besides
      there are few studies with use of these adjuvants during the perioperative period, the
      intravenous injection of local anesthetic still arouses oddity among professionals;
      therefore, the investigators interest in the subject.

      The patients underwent a prospective, randomized, double blind study, in which the examiners
      responsible for intra and post-operative will not know which group they were randomly
      allocated: Lidocaine group (n = 30); Lidocaine and Magnesium group (n = 30); Magnesium group
      (n = 30) or Remifentanil group (n = 30). Rapid infusion of 0.9% saline 500 ml, in the M and
      LM group, is added to this solution the loading dose of magnesium sulfate with 50 mg/kg and
      in group L will only be infused saline 0.9% . Two infusion pumps containing the result of
      randomization: Lidocaine 3 mg/kg/h and 0.9% saline (L group); magnesium sulphate 15 mg/kg/h
      and 0.9% saline (M group); lidocaine 3 mg/kg/h and magnesium sulphate 15 mg/kg/hr (LM group);
      and Remifentanil group (R group).

      In the clinical record, the following information will be emphasized: Blood pressure and
      heart rate intraoperative, perioperative side effects, quantify pain by Visual Analogue Scale
      (VAS) (ranging from 0 to 10 cm, zero being found when the patient is no pain and ten, with
      maximum or unbearable pain), Verbal Rating Scale (VRS), consisting of a list of phrases (no
      pain, mild pain, moderate pain, intense pain, maximum pain) and qualification of pain
      assessed by the amount of analgesics required postoperatively and the time to request them.

      The results were analyzed statistically with the Statistical Package for Social Sciences
      (SPSS) version 22 (SPSS Inc., Chicago, IL, EUA) using parametric and nonparametric tests,
      depending on the nature of the variables studied. Data were tested for normality using the
      Shapiro-Wilk test. Measures of central tendency (means) and dispersion (standard deviation)
      were used. The level of significance was set at < 0.05. The following tests were used:
      Mann-Whitney test for age, duration of anesthesia and surgery, time to first analgesic
      supplementation, total amount of analgesics, pain intensity; Student t-test for weight and
      height.
    

Intervention name(s): Remifentanil infusion; Lidocaine infusion; Magnesium sulphate infusion; Magnesium sulphate and Lidocaine infusion
Intervention type(s): Drug; Drug; Drug; Drug
Intervention description(s): Patients in Remifentanil group received an intravenous bolus injection of 2 mg/kg lidocaine followed by a continuous remifentanil infusion of 0,1 mcg/kg/min.; Patients in Lidocaine group received an intravenous bolus injection of 2 mg/kg lidocaine followed by a continuous lidocaine infusion of 3 mg/kg/hr.; Patients in Magnesium group received an intravenous bolus injection of 50 mg/kg magnesium sulphate plus an intravenous bolus injection of 2 mg/kg lidocaine followed by a continuous magnesium sulphate infusion of 15 mg/kg/hr.; Patients in Magnesium and Lidocaine group received an intravenous bolus injection of 2 mg/kg lidocaine plus 50 mg/kg magnesium sulphate followed by a continuous lidocaine infusion of 3 mg/kg/hr plus 15 mg/kg/hr magnesium sulphate
Other intervention name(s): Remifentanil hydrochloride; Lidocaine hydrochloride; Magnesium sulphate; Magnesium sulphate, Lidocaine hydrochloride
Intervention MeSH terms: Lidocaine; Magnesium Sulfate; Remifentanil
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: Intravenous lidocaine; Magnesium sulphate; Mastectomy; Pain