Vagal reflex
Including.
1, oculocardiac reflex: compression can cause a decrease in heart rate, cardiac arrest; nausea, vomiting, etc.
2, carotid sinus reflex: stimulation can cause blood pressure changes, heart rate drop, reflex syncope, arrhythmia.
3, vagus-vagus reflex: the most common, the vagus nerve distribution area if stimulated compression, through the heart inhibitory nerve fibers inhibit the heart, can cause arrhythmias, and even arrest.
The following areas are most common: otorhinolaryngology, heart, lung, trachea, esophagus, liver, stomach, gallbladder, pancreas, spleen, small intestine, large intestine, rectum, bladder, and reproductive system. The following procedures are more common: otorhinolaryngology – biliary tract – heart – neck – esophagus. The rest are mostly incidental. Surgical compression or irritation in these areas can cause vagal-vagal reflexes, leading to unexpected cardiovascular changes.
Diagnosis.
It can occur at any age, and is more likely to occur in pediatric patients with reflex laryngospasm, tonsils, cleft palate repair, and direct laryngoscopy, and in adults with gallbladder surgery.
In addition to the mechanical stimulation of surgery, the following factors increase its incidence.
Sudden unexpected signs of death
Malignant hyperthermia is an acute, fatal genetic metabolic disease. It is characterized by general anesthesia inhalation, and succinylcholine in susceptible individuals, and is characterized by hyper-metabolism of skeletal muscle. Early mortality rate of 70%-90% 15 years of age accounted for 52, 1%, 56, 8% of males.
All volatile anesthetics can cause, and the incidence is high when combined with scopolamine.
Treatment.
1, comprehensive treatment: discontinuation of drugs, pure oxygen inhalation, hyperventilation, support.
2, injection of dantrolene: 2, 5mg/K,i intravenous, can be repeated until the symptoms are controlled.
3.Correction of expiratory acid: blood gas guidance, or direct administration of sodium bicarbonate 1-2mmol/Ki intravenous.
4.Lower body temperature: measure central body temperature, cold saline irrigation of stomach, bladder, rectum or other cooling measures.
5.Anti-arrhythmic: but not with calcium channel blockers.
6.Anti-hyperkalemia: Hyperventilation, NaHCO3, sedation of glucose and insulin, calcium chloride or calcium gluconate for fatal hyperkalemia.
7, diuretic: mannitol, tachyphylaxis, etc.
8, cardiac arrest: pay attention to treatment with anti-hyperkalemia. Prevention: prepare dantrolene.
Pulmonary artery embolism
1.Cause: Embolism including thrombus is the most common, and it is most common in calf deep vein and femoral vein thrombosis, such as indwelling catheter,, air embolism, fat embolism, amniotic fluid embolism, cancer embolism, etc. The incidence of fatal pulmonary embolism: 0,1-0,8% for general elective surgery, 0,3%-1,7% for elective hip surgery, and 4%-7% for emergency hip surgery.
2, pathophysiology: pulmonary artery embolism with damage to lung tissue, pulmonary circulation, right heart and left heart function, etc.
Medium to low body temperature.
Associated with the following factors.
(1) severe hypothermia in the peripheral environment;
(2) Short-term infusion of large amounts of cold fluids, including lavage fluid, thoracoabdominal irrigation fluid;
(3) Central hypothermic effect of some anesthetic drugs;
(4) Loss of water and heat from the respiratory tract in open or semi-confined inhalation anesthesia.
Manifestations: decreased heart rate, blood pressure, SPO2, confusion, no spontaneous breathing, unequal body temperature.
Treatment: rapid rewarming, close monitoring, respiratory control, CVP, until recovery.
Acute pulmonary edema.
Causes.
1, excessive cardiac load: excessive fluid input, application of vasoconstrictors, etc., especially in children and cardiac insufficiency;
2, cardiac insufficiency;
3, hypoproteinemia: the original or excessive input of crystalloid to make the blood dilution;
4.Airway obstruction: severe hypoxia and CO2 accumulation, misaspiration, allergy, etc.
Performance: R shortness, TV drop, coarse breath sounds in both lungs, blistering sound, SPO2 drop, etc;
Treatment: control the infusion of fluids, give cetiran, tachyphylaxis, aminophylline, dexamethasone, etc.
Acute cerebral edema.
Possible causes.
1, acute dilation of cerebral vascular paralysis, increased cerebral blood flow;
2, surgery on brain tissue extrusion or rough operation;
3, body position;
4, hypoxia, CO2 accumulation;
5, transfusion of fluids and blood in excess;
6.Anesthesia drug itself;
7, too shallow anesthesia.
Presentation: sudden increase in intracranial pressure, brain tissue expansion out of the bone window, blood pressure and heart rate rise first and then fall.
Treatment: Adequate oxygen supply, appropriate hyperventilation, mannitol diuresis, hormones, etc.
Prevention: for the cause, anesthetics should avoid inhalation drugs and use intravenous anesthetics such as fentanyl, SP, etomidate, and inotropic drugs are appropriate to use non-depolarizing inotropic drugs.