After the general anaesthetic tracheostosis, severe bronchospasm "silent lung" was successfully treated for 1 case.

. 1. Case Information
1.1 Medical History Review
female, 44 years old, 172 cm tall and weighing 60 kg. Because of the "uterine fibroid" consultation, it is proposed in the general anesthesia down "abdominal mirror uterine fibroid removal surgery and ring surgery." The patient is healthy, has no chronic underlying disease, denies the history of drugs, food allergies. Patients who complain of coughing and coughing more when they have a cold on weekdays have been diagnosed with "bronchodilating" in local hospitals, as no previous imaging data and laboratory test results have been found, the specific condition is unknown.
patients had a caesarean section in 2002, the admission six months ago in the local hospital under general anesthesia under the implementation of "breast fibroid stoicectomy", anesthesia and surgery process is smooth, the patient recovered well after surgery. Preoperative visit to assess the patient's clinical heart function Level I, Airway assessment Mallampati grade I, opening mouth is greater than 3 fingers, cervical back elevation, amyle distance and chest distance did not see abnormal signs. The patient had a mild upper respiratory tract infection before complaining to 7d, occasionally coughing, coughing sputum, and having a normal body temperature (about 36.7 degrees C). Preoperative chest X-ray and ECG test results did not show significant abnormalities. Laboratory test results: white blood cells 9.17 x 109g /L (normal value 4.00 x 109 to 10.00 x 109g/L), neutrophils percentage 50.1% (normal value 50.0% to 70.0%), eophilic cell percentage 6.2% (normal value 0.5% to 5.0%), blood function test results were not abnormal.
1.2 anaesthetic after
patients enter the operating room after the routine open vein pathway, connected monitoring, monitoring blood pressure 100mmHg/65mmHg (1mmHg -0.133kPa), heart rate 72 times / min, in the absence of oxygen SpO2 97%. After the mask pure oxygen pre-absorption 5min, by the intravenous pot into the midazolam (production batch number: 20180509, Jiangsu Enhua Pharmaceutical Co., Ltd.) 1mg, Ondan Shijun (production lot number: 8J01610 16, Qilu Pharmaceutical Co., Ltd.) 4mg, Dexamethason (production lot number: 1805031, Tianjin Jinyao Pharmaceutical Co., Ltd.) 5mg and Fentanyl (production lot number: 8D06031, Yichang Renfu Pharmaceutical Co., Ltd.) 100?g, intravenous push Lidocain (production lot number: 201808011, so chengpharmaceutical co., Ltd.) 20mg, propofol (production lot number: X18007B, CordenPharmaS.P .A, Italy) 150mg, Roco brominated ammonium (production lot number: 12006938, Hameln PharmaceuticalsGmbH, Germany) 50mg, implementation of rapid anaesthetic induction, mask ventilation smooth, chest fluctuations and good.
intravenous injection of rocum brominated ammonium 3min, the use of 7.0 ordinary trachea catheter (Model: 16L0182JZX, Covidien, Mexico) to implement the trachea intubation, intubation process is smooth, fixed catheter in depth from the door teeth 22 cm Subsequently, in hand-controlled ventilation, feel great resistance, "iron lung" feel, hearing double lung no breathing sound, because of suspected of the occurrence of airway intubation, so quickly remove the trachea catheter;
then use visual laryngos (Model: PV112042, VerathonMedicalULC, Canada) to complete the trachea intubation operation under the direct sound door, after confirming that the trachea catheter is located in the airways, the two hands squeeze breathing bladder resistance is still very large, still "iron lung" feel, hearing double lung breathless sound, connecting breathing machine (model: S/5Advance, Datex-Oh Meda Inc., U.S.) line mechanical control capacity ventilation, no end-of-the-end carbon dioxide (end-tidal carbon dioxide, EtCO2) waveform, after the rapid elimination of circuit blockage, slip, intubation too deep, pulmonary edema, pulmonary embolism, gas chest, severe allergic reactions and accidental inhalation, highly suspected that the patient at this time after a clinically rare anaesthetic severe bronchospasm, that is, "silent pulmonary. "
1.3 Anesthetic Treatment
in response to this clinical judgment, a series of treatments were quickly given, including increasing the concentration of heptalone (production batch number: S04C829, Baxter Healthcare, Spain) to 8%, fresh oxygen flow to 8L/min, spraying salbutamol aerosols into the patient's trachea catheter (production batch number: K63J, GlaxoEnS.A. No breathing sound, in the intravenous injection of epinephrine (production batch number: 1709301, Tianjin Jinyao Pharmaceutical Co., Ltd.) after 10 sg, gradually appear irregular EtCO2 waveform, hearing double lung snarling, and then each interval of 2 min vein sizzling 10 sg, a total of 30 sg of epinephrine, while intermittent injection of salinalcopine gasol steam ingenual spray in the trachea duct, 2 times, a total of 4 times.
active treatment, the more regular EtCO2 waveform gradually appeared, at which point the hearing double lung is full of wheming sound. Subsequently, the hydrogenated pine (production batch number: 021703066, Tianjin Biochemical Pharmaceutical Co., Ltd.) 100mg dissolved in 100 ml of physiological saline intravenous drip. Throughout the process, SpO2 was reduced to a minimum of 88% and gradually reverted to 100%. For patients to cycle stability, MAP70 to 80mmHg, airway pressure 18 cm H2O (1 cmH2O s 0.098kPa), EtCO2 waveform gradual rule, PETCO2 stable to 35 to 40mmHg, hearing double lung sound significantly reduced, gradually reduce the concentration of heptal-fluoroeh ether inhalation and oxygen flow.
during the operation, heptafluoretherine inhalation concentration of 3.5%, oxygen flow 2L/min, and intermittently give fentanyl a total of 300 sg, patients' life signs are stable, MAP70 to 80mmHg, airway pressure 15 to 25 cmH2O, PETCO2 maintained at 35 to 42mmHg. The operation lasted about 1.5h, sucking sputum in a deep anaesthetic state after surgery, and the hearing patient's double lung snarling sound was significantly less than before. After the patient's sober state successfully pulls the tube, pure oxygen mask ventilation, SpO2 can be maintained 100%, the hearing of the double lung small airway snarling slightly. Infusion sodium lactate fluid 1700 ml, urine volume of 50 ml. After surgery into pacu monitoring observation, in the absence of oxygen, SpO2 can still maintain more than 95%, the patient is clear,cycloloopation, the main complaint no discomfort, return to the ward.
2. Discussion
2.1 Analysis of the Causes of "Silent Lung"
"Silent Lung" usually refers to a critical sign of a howling, breathing tone decreased or disappeared in a bronchoscosis asthma sufferer due to strong broncho spasms or extensive mucus blockage. This case patient has previously been diagnosed as "bronchodliature", because no high resolution CT examination, so it is not clear whether there is an airway structure change. Patients complain that there is no obvious asthma attack, but cough, cough sputum more when cold, before admission to the hospital has a slight upper respiratory tract infection, occasional cough, cough sputum, indicating that the patient's airways are still in a high reaction state, and preoperative laboratory examination has indicated an increase in the percentage of eosic cells;
after surgery by respiratory medicine consultation, this patient is more likely to be diagnosed as "cough-variant asthma" (i.e., no typical asthma attack, coughing, coughing sputum as the only atypical sign of the special type of asthma). For patients with similar asthma atypical, anesthesiologists must carefully evaluate, fully prevent and give active and effective treatment.
2.2 "Silent Lung" clinical manifestations and diagnosis
perioperative period severe bronchospasm, that is, "silent lung", is a critical disease of the airways, with the characteristics of acute onset, rapid progress of the disease, its clinical performance for its diagnosis is of great significance, including hearing double lung no breathing sound, artificial ventilation resistance is greatly "iron lung" hand, airway pressure sharply increased, gas tube intubation and other hypothelie. The "silent lung" during the perioperative period has a similar pathogenesis with asthma. Therefore, for patients with high airway reactions such as upper respiratory tract infections, asthma and allergic physiques, anesthesiologists should be vigilant during the process of anesthesia induction and tube extraction.
in general anaesthetic, due to cough reflexes are inhibited, airway mucosa function is impaired, pharynx muscle tone is reduced, muscle function is inhibited and airway secretions increase, such as a series of physiological changes, with the occurrence of "silent lung" has a clear correlation. In particular, asthma patients with underfull symptoms and patients with a long history of smoking and with a recent upper respiratory tract infection were significantly more likely to have a "silent lung" during perioperative surgery.
it should be noted that some narcotic drugs can induce the occurrence of "silent lung" during perioperative surgery, for example, aquukamon, ammonium mevidau and other muscle relaxive drugs have histamine release effect, so it should not be used in asthma patients. For patients with specific allergies (e.g. patients with allergic rhinitis), drugs with histamine release are more likely to induce bronchospasm, or even "silent lung".
the patient did not use the above-mentioned drugs that can induce "silent lung", but the ammonium of the bromine has a slight group ammonium release effect, so it is not excluded as one of the predisposing factors. Although there have been recent reports of ammonium aquorin in the body that causes histamine release, it may be safer to use ammonium aquor ammonium in the body of psifoama.
2.3 "silent lung" prevention
in order to prevent the occurrence of perioperative period "silent lung", before surgery should learn more about the patient's medical history, upper respiratory tract infection and asthma patients, control the condition at a stable level, before surgery need to carry out breathing function determination, if necessary, please respiratory medicine consultation. The anaesthetic induces full pre-oxygenation before and ensures adequate anaesthetic induction depth. Takiguchi and other studies have shown that the use of Lidoka in front of the trachea intake to perform adequate airway surface anesthesia can reduce the risk of bronchospasm and "silent lung", but to control the speed and concentration of spraying, to avoid its stimulation of the airways caused by airway contractions. Giving Lidocain 1.5 mg/kg before anaesthetic induction can also reduce the airway reaction during trachea intubation.
in addition, in order to prevent the occurrence of perioperative period "silent lung", it is also necessary to maintain the appropriate anaesthetic depth during the perioperative period, and pay attention to the intra-airway operation, the action is gentle, as far as possible to reduce the irritation of the airway. In the shallow anaesthetic state, analgesic, muscle loose incomplete and trachea intubation, trachea tube extraction, sputum and other intra-airway operations and surgical pull and other stimulation are significantly related to the occurrence of "silent lung" during perioperative surgery. Moreover, when the trachea catheter is inserted into too deep to stimulate the protrusion, it can cause choline nerve euphoria and induce bronchospasm, and in severe cases it can also lead to the occurrence of "silent lung".
the patient in the anaesthetic induction process, do not exclude due to the infusion line bending, infusion speed is too slow, resulting in the drug did not fully enter the vein line, and in the case of muscle relaxation drugs are not fully effective, the implementation of the first trachea intubation operation, trachea catheter on the airway strain, intubation operation is not gentle enough, etc. may become the "silent lung" of the induced factors.
in particular, it should be noted that once the trachea intubation appears to be a hearing double lung without breathing sound, artificial ventilation resistance is greatly "iron lung" hand feeling, airway pressure increases sharply, invisible EtCO2 waveform, should not rush to remove the trachea catheter, first need to use the visual laryngosor or soft mirror and other airway management tools to confirm whether the trachea tube is in the airway, thus effectively avoid blind extraction, re-intubation and other mechanical stimulation of the airway. Because it may not only aggravate the air duct spasm state, or even may be due to the failure to complete the re-trachea intubation operation, can not establish a safe and effective airway, thus threatening the patient's life during the perioperative period.
inhaling the antitherdrug heptafluoroetheration has a strong bronchodilating effect, and is an ideal drug for the prevention and emergency treatment of bronchospasm patients. For patients who are generally in good condition and hemodynamically stable, intravenous anesthesia induction can be used with propofol, and for patients with unstable hemodynamics, ketamine or resphenyls may be considered. Although opioids can increase airway reactivity, fentanyl, riffentanus, and schofentanil remain the preferred drug in clinical practice for anaesthetic induction and anesthesiology in highly reactive patients of the airways due to their strong analgesic effects.
2.4 "silent lung" treatment
if the clinical performance of patients and "silent lung" is very similar, and quickly eliminate circuit obstruction, slip, intubation too deep, pulmonary edema, pulmonary embolism, gas chest, severe allergic reactions and accidental inhalation and other factors, should be quickly given positive and effective treatment. These include: (1) immediately increase the concentration of inhale pure oxygen, increase oxygen flow, perform manual ventilation to maintain oxygenation, and increase the concentration of inhalation of heptafluoroetherine to the maximum, and/or infusion propofol increases the depth of anesthesia. (2) The application of beta 2 receptor agonists, such as salbutamol aerosol sprayed into the trachea ducts 8 to 10 to the trachea to dilate the bronchial tube. (3) Epinephrine due to beta 2 receptor agitation, dilating bronchial action is strong, and its alpha receptor action can improve mucosal edema, is the first time to relieve the "silent lung" preferred drug, usually the first 10 to 30 sg intravenous drip, and according to the specific circumstances of the patient's "silent lung" relief gradually increase the dose, but due to the role of the alpha receptor of epinephrine, need to be closely monitored to prevent tachycardia and hypertension. (4) hydrogenated pine and Astrong dragon has anti-inflammatory, reduce airway edema, the use of hydrogenated pine 100mg or Aqiang dragon 80mg intravenous drip, are conducive to better airway management.
2.5 "silent lung" tube extraction process precautions
after surgery, in the deep anaesthetic state of the extraction of the tube, can effectively reduce the risk of bronchospasm and larynx spasms. Before pulling the tube, we should fully suck sputum and clean up the secretions of the pharynx cavity in the state of deep anesthesia. During the pull-out process, it is necessary to ensure good ventilation and be alert to the occurrence of accidental suction. Xinsming as a muscle relaxant antagonist can increase bronchial secretions, and improve airway reactivity, which can easily cause bronchospasm, so the use of neosisoms need to be cautious. In addition, the injection of salbutamol aerosols into the trachea duct scanol before the extraction of the tube and the intravenous Lidocain can also be effective in reducing airway reactivity.
2.6 "Silent Lung" postoperative airway management
for "silent lung" high-risk patients or perioperative surgery has occurred in the "silent lung" patients, need to strengthen postoperative airway management, as far as possible to avoid adverse stimulation of the airways. This includes adjusting the pillow height of patients to prevent gastroesophageal reflux, applying acid inhibitors to patients with gastroesophageal reflux disease, and severe postoperative pain and stress anxiety.