RU2312680C1 - Method for controlling respiratory disorders in administering sedation to patients when giving epidural anesthesia - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves applying sedation and setting laryngeal mask after having done epidural anesthesia. Next, controlled mechanical lung ventilation is carried out without total myorelaxation being applied in CMV mode selecting respiration volume being equal to 6-8 ml/kg of body weight, peak flow value of 50-65 l/min in applying rectangular gas mixture injection mode or 65-85 l/min in applying descending gas mixture injection mode. Inspiration-to-expiration ratio is selected 1:1.3-1:1.7, oxygen fraction FiO₂ in inhaling being equal to 0.25-0.3, forced breathes frequency equal to 10-16 per 1 min, basic positive pressure value at the expiration end being equal to 3-4 cm of water column. The operation being over, the laryngeal mask is removed and auxiliary non-invasive lung ventilation with air and oxygen mixture is applied via facial mask in breathing support mode with PSV pressure. The support pressure is equal to 10-15 cm of water column on inhaling, oxygen fraction FiO₂ in inhaling being equal to 0.25-0.3, positive pressure value at the expiration end being equal to 2-3 cm of water column, trigger sensitivity being 2-3 l/min. Respiration support is continued until respiration volume is not less than 6-7 ml/kg of body weight.

EFFECT: reduced risk of negative consequences; accelerated respiratory rehabilitation.

Description

The invention relates to medicine, to the field of epidural anesthesia and sedation, ensuring the lack of consciousness of patients during surgery.

A known method for the correction of respiratory disorders during deep sedation in patients with epidural anesthesia (EA) is mechanical ventilation (mechanical ventilation) with total muscle relaxation and tracheal intubation [3, 8]. However, the use of mechanical ventilation is associated with a risk of complications and side effects associated with total muscle relaxation, tracheal intubation and respiratory rehabilitation of patients after mechanical ventilation [5, 7].

The proposed method for the correction of respiratory disorders during sedation in patients with EA includes respiratory support.

The proposed method for the correction of respiratory disorders is characterized in that during EA and patient sedation, respiratory support is performed through a laryngeal mask (LM) without total muscle relaxation in the controlled mechanical ventilation mode CMV (Controlled Mechanical Ventilation in English) [2]; after surgery, cessation of sedation and removal of LM for the purpose of respiratory rehabilitation of patients, additional non-invasive ventilation of the lungs (VNVL) [1] is additionally used with an air-oxygen mixture through a face mask in the PSV (Pressure Support Ventilation in English) [2] .

The method is as follows.

After performing according to the generally accepted method [3], the patient’s EA is transferred to the supine position. After making sure that the sensorimotor block reaches the required level, they perform sedation of the patient with propofol, turning off consciousness at a dose of 1.5 to 2.5 mg / kg [6] and proceed with the installation of LM according to generally accepted rules [4]. The LM connector is connected to a breathing apparatus that allows for CMV and PSV modes: Puritan-Bennett 760, Puritan-Bennett 740 (USA), Servoventilator-C900 (Siemens, Sweden), Erica and Elvira "(" Gambro "Sweden) and others. Sedation of patients during surgery is maintained by continuous infusion of propofol at a rate of 2-3 mg / kg / hour [6].

The proposed method for the correction of respiratory distress after installing LM in CMV mode with volume control is carried out with the oxygen fraction in the inhaled gas mixture (FiO ₂ in the English language) [2] 0.3-0.4 Puritan Bennett 700 series respirator (740 or 760) with the following parameters:

1) tidal volume (DO) - 6-8 ml / kg body weight;

2) peak flow (Flow pic. In the English language abbreviation) [2] - 50-65 l / min with a rectangular form of injection of a gas mixture;

3) Flow pic. 65-85 l / min in a descending form of blowing a gas mixture;

4) the ratio of inspiration to exhalation (Ti: Te) [2] is selected by changing the values of DO and peak flow. The optimal ratio is 1: 1.3-1: 1.7.

5) the frequency of forced breaths is set in the range from 10 to 16 per minute, taking into account the size of minute ventilation (l / min), which is set by the formula: patient weight (kg) / 10;

6) sets the value of the base positive pressure at the end of expiration (PDKV) [2] - 3-4 cm of water. Art.

After the operation is completed and the patient is awakened, the LM is removed, after which, for the purpose of respiratory rehabilitation, VNVL is performed in PSV mode through the face mask.

To do this, set the following parameters on the respirator:

1) the initial level of pressure support (PS - Pressure Support in the English language abbreviation) [2] 10-15 cm of water. st .;

2) the level of PEEP 2 -3 cm of water. st .;

3) trigger sensitivity (with flow control) 2-3 l / min;

4) the temporary growth factor and exhalation sensitivity are selected on the Puritan Bennett model 760 individually, taking into account the comfort of the applied support for the patient;

5) apnea parameters - 15 seconds (time after which there is an automatic switch to CMV mode).

The technical result of the proposed method for the correction of respiratory disorders is as follows. Since EA provides adequate sensory and motor blockade in the area of surgical intervention, patients sedation is reduced to the introduction of hypnotic, which ensures the absence of consciousness and reaction to the presence of LM in the upper respiratory tract. The method for correcting respiratory disorders through LM in CMV mode under these conditions allows for adequate breathing during surgery without the complications and side effects characteristic of total muscle relaxation and intubation of the trachea, followed by quick postoperative respiratory rehabilitation of patients in PSV mode through the facial mask.

Example.

Patient M., 64 years old, with a diagnosis of uterine fibroids, the estimated scope of the operation - amputation of the uterus, the selected method of anesthesia - EA. At the request of the patient, sedation with a lack of consciousness during the operation was planned. In the position on the left side under local anesthesia, the epidural space was punctured at the level of Th ₁₂ -L ₁ and catheterized by an epidural catheter in the cranial direction by 5 cm. Bupivacaine 0.5% 15.0 was inserted into the epidural catheter. After 25 minutes, the upper limit of the sensor block was established at the level of Th ₇ . The patient was completely sedated with propofol infusion at a dose of 2.5 mg / kg, and then LM No. 4 was established by a standard technique. The LM connector was connected to a Puritan-Bennett 760 breathing apparatus. Correction of respiratory distress after installing LM in CMV mode with volume control was carried out with an oxygen-air mixture (FiO ₂ = 0.3) with the following parameters of forced inspiration: DO - 6 ml / kg body weight; Flow pic. - 60 l / min with a rectangular shape of the injection of the gas mixture; Ti: Te -1: 1.5; frequency of forced breaths 12; the value of PDKV - 3 cm of water. Art. Maintenance of patient sedation during surgery was carried out by continuous infusion of propofol at a rate of 3 mg / kg / hour.

After the operation was completed and the patient woke up, the patient was removed with LM, after which, for respiratory rehabilitation, VNVL was performed in PSV mode through the face mask, selecting individual NVVL parameters, focusing on achieving the patient's respiratory comfort. VNVL parameters: FiO ₂ 0.3, inspiratory support pressure 10 cm of water. Art., PDKV - 2 cm of water. Art., trigger sensitivity 3 l / min, DO - 620 ml.

After surgery, the patient was transferred to the intensive care unit for observation and treatment in the early postoperative period.

Information sources

1. Valley O.A. Anesthesiology and resuscitation. Textbook for high schools. M .: Publishing house GEOTAR-MED, 2002. - P.66.

2. Kassil V.L., Leskin G.S., Vyzhigina M.A. Respiratory support. -M .: Medicine, 1997.-S.63, 124, 295-298.

3. Koryachkin V.A., Strashnov V.I. Spinal and epidural anesthesia. - St. Petersburg: Medical Publishing House, 2000. - P. 49.

4. Marchenko A.V., Epstein S.L., Berdikyan A.S. Laryngeal mask. Benefits of use and methodological difficulties. // Bulletin of intensive care. - 2002. - No. 3. - S. 38-44.

5. Guide to anesthesiology. Ed. A.A. Bunyatyan. M .: Medicine, 1994.-S.186-195.

6. Smith I., White P.F. Total intravenous anesthesia. Clinical management: Trans. from English - M. - St. Petersburg: Binom-Nevsky dialect, 2002 .-- 176C.

7. Difficulties in tracheal intubation. Per. from English Ed. I.P. Latto, M. Rosen. M .: Medicine, 1989, C 68-88.

8. The Nutcrackers B.C. Epidural anesthesia. - L .: Medicine, 1976. - P.140

Claims (1)

A method for the correction of respiratory disorders during sedation in patients under epidural anesthesia, including respiratory support, characterized in that the respiratory support is carried out through a laryngeal mask without total muscle relaxation in the controlled mechanical ventilation mode of the CMV with the following parameters: respiratory volume of 6-8 ml / kg of body weight, peak flow of 50-65 l / min with a rectangular form of blowing the gas mixture or 65-85 l / min with the descending form of blowing the gas mixture, inspiratory to expiratory ratio 1: 1.3 ÷ 1: 1.7, oxygen fractions on inspiration FiO ₂ 0.25-0.3, frequency of forced inspirations from 10 to 16 per min, the value of the base positive pressure at the end of exhalation is 3-4 cm of water. Art., after the operation is completed and the laryngeal mask is removed, additional non-invasive ventilation of the lungs with the air-oxygen mixture is additionally applied through the face mask in the breathing support mode with PSV pressure at the inspiration support pressure of 10-15 cm of water. Art., oxygen fractions on inspiration FiO ₂ 0.25-0.3, positive pressure at the end of exhalation 2-3 cm of water. Art., trigger sensitivity of 2-3 l / min, until a tidal volume of at least 6-7 ml / kg of body weight is reached.