By W. Thorus. Wilmington College, Wilmington Ohio.
Several studies seem to indicate that patients treated with pentobarbital have fewer treatment failures and breakthrough seizures order disulfiram, but more frequent episodes of hypotension buy discount disulfiram 500 mg line. If the bursts contain electrographic seizure activity order disulfiram canada, the coma should be deepened, at times to virtual electrocerebral silence. Phenobarbital may be used as a bridge if initial weaning off pentobarbital results in recurrence of seizures. The patient should also be started on antiepileptic medication appropriate for long-term management, given as a loading dose if appropriate. The high-fat and low-protein/carbohydrate diet is administered via nasogastric tube which subsequently induces a metabolic shift toward acidosis, resulting in ketonuria, which can be present within a few days of initiation of the diet. Silbergleit R, Durkalski V, Lowenstein D, et al: Intramuscular versus intravenous therapy for prehospital status epilepticus. Knake S, Gruener J, Hattemer K, et al: Intravenous levetiracetam in the treatment of benzodiazepine refractory status epilepticus. Hofler J, Unterberger I, Dobesberger J, et al: Intravenous lacosamide in status epilepticus and seizure clusters. Rossetti A, Reichhart M, Schaller M, et al: Propofol treatment of refractory status epilepticus: a study of 31 episodes. Kalviainen R, Eriksson K, Parviainen I: Refractory generalised convulsive status epilepticus: a guide to treatment. It is the most common cause of rapidly progressive weakness due to peripheral nerve involvement, with an annual incidence of 0. Other antecedent events include immunization; general surgery and renal transplantation; Hodgkin’s disease; and systemic lupus erythematosus [2,3]. The major feature is weakness that evolves rapidly (usually over days) and classically has been described as ascending from legs to arms and, in severe cases, to respiratory and bulbar muscles. Weakness may, however, start in the cranial nerves or arms and descend to the legs or start simultaneously in the arms and legs . Approximately 50% of patients reach the nadir of their clinical course by 2 weeks into the illness, 80% by 3 weeks, and 90% by 1 month . Several years often pass between episodes, differentiating them from patients with treatment-related fluctuation, where worsening occurs within the first 8 weeks of disease onset after initial improvement/stabilization . Within a few days, a patient may become quadriparetic and become respirator dependent, or the illness may take a benign course and after progression for 3 weeks produce only mild weakness of the face and limbs. Physical Findings In a typical case of moderate severity, the physical examination discloses symmetric weakness in proximal and distal muscle groups with attenuation or loss of deep tendon reflexes (Table 152. If the attack is particularly severe and axons are interrupted, muscles undergo atrophy and scattered fasciculations may be seen after a number of months. Respiratory muscles are often involved, and 10% to 25% of patients require ventilator assistance  within 18 days (mean of 10 days) after onset . In the Miller Fisher variant , however, ophthalmoplegia occurs in combination with ataxia and areflexia, with little limb weakness. Autonomic dysfunction takes the form of excessive or inadequate activity of the sympathetic or parasympathetic nervous system, or both . Other changes include transient bladder paralysis; increased or decreased sweating; and paralytic ileus. The pathophysiology of these changes is not completely understood but may be caused by inflammation of the thinly myelinated and unmyelinated axons of the peripheral autonomic nervous system. The cell count may be slightly increased but rarely exceeds 10 cells per µL; the cells are mononuclear in nature. The amplitude of the evoked motor responses may be reduced because of axon loss or distal nerve conduction block, and the responses are frequently dispersed because of differential slowing along still-conducting axons [8,24]. Because the pathologic process may be restricted to spinal nerve roots and proximal nerve segments, routine nerve conduction studies early in the course of the neuropathy may be normal initially. In such cases H-reflexes are often absent and F- responses are abnormal (absent or prolonged in latency). The electrodiagnostic findings in the Miller Fisher syndrome are indicative of a sensory neuronopathy with reduced or absent sensory responses throughout despite normal motor studies. There may be evidence of previous viral or mycoplasma infection, such as lymphopenia or atypical lymphocytes. In some cases, evidence of recent viral infection may be sought by measuring antibody (immunoglobulin [Ig] M) titers against specific infectious agents, especially cytomegalovirus, Epstein–Barr virus, and C. Critical illness polyneuropathy is an axonal sensory and motor polyneuropathy characterized by difficulty weaning from the ventilator, distal greater than proximal muscle weakness, and reduced or absent reflexes that develop in patients with sepsis and multiorgan failure . Patients have variable degrees of generalized weakness, including respiratory muscles, and this is often recognized when a patient has difficulty weaning from the ventilator. Disorders of the Neuromuscular Junction In patients with myasthenia gravis, limb weakness is predominant proximally and almost always associated with ocular and sometimes pharyngeal muscle weakness (see Table 152. Botulism may also cause acute weakness 6 to 36 hours after ingestion of the toxin formed by Clostridium botulinum. The condition is characterized by weakness of cranial nerve–innervated muscles, autonomic abnormalities (unreactive pupils and ileus), and occasional respiratory muscle weakness necessitating ventilator assistance. Electrodiagnostic findings of low compound motor action potential amplitudes with post-excercise facilitation are key in diagnosing this condition. Disorders of Peripheral Nerve Tick paralysis is produced by a toxin contained in the head of the tick Dermacentor andersoni or D. Weakness associated with sensory impairment develops rapidly after the tick has embedded itself into the victim, usually over 1 to 2 days. Patients complain of face, finger, and toe numbness and then note the development of rapidly progressive descending paralysis, which may involve respiratory muscles. Organophosphorus insecticide toxicity causes a short-lived acute cholinergic phase marked by miosis, salivation, sweating, and fasciculation followed in 2 to 3 weeks by an acute axon-loss polyneuropathy . An intermediate syndrome occurring 24 to 96 hours after the cholinergic phase and characterized by multiple cranial nerve palsies and respiratory failure has also been described . Attacks of paralysis are precipitated by ingestion of a variety of drugs, including alcohol, barbiturates, estrogens, phenytoin, and sulfonamides. The diagnosis may be established by demonstrating increased levels of porphobilinogen and δ-aminolevulinic acid in the urine. During the height of the infection, there is numbness of the lips and paralysis of pharyngeal and laryngeal muscles.
Oxygen should be used in all asthmatic patients who present to the hospital with an exacerbation; the goal oxygen saturation is 95% or higher because hypoxemia may worsen initially with bronchodilator therapy purchase genuine disulfiram online, as a result of worsening ventilation–perfusion mismatch cheap disulfiram online master card. Other therapies are directed at the rapid reversal of bronchoconstriction and airways inflammation (see Chapter 172) trusted 500mg disulfiram. Bronchoconstriction is managed with inhalation of selective rapid- onset β2-agonist and anticholinergic agents, given at 20-minute intervals or continuously. Typically, nebulized medication is given prior to intubation and then switched to metered dose inhaler after intubation. The doses of albuterol and ipratropium are the same for both obstetric and nonobstetric patients presenting with status asthmaticus . The effects of inhaled agents are predominantly local, which should decrease the amount of fetal exposure, and selective β2-agonists do not adversely affect uterine blood flow. There has been no evidence of fetal injury from the use of either systemic or inhaled β-adrenergic agonists , although neonates exposed to systemic β-agonists just prior to delivery have demonstrated tachycardia, hypoglycemia, and tremor. Systemic glucocorticoids should be initiated promptly in all pregnant patients presenting with an acute asthma exacerbation who are not responding to one or two inhalational treatments with a β2-agonist . Institution of glucocorticoids helps to reverse airflow obstruction and, thereby, decrease the amount of high-dose β-adrenergic agonist therapy needed. However, the same dose ranges are used in both obstetric and nonobstetric adults, prednisone or methylprednisolone 120 to 180 mg per day in three or four divided doses for the first 48 hours and then 40 to 60 mg a day until clinical improvement is significant and the peak expiratory flow has increased to 70% of predicted or personal best . In rodents that were given glucocorticoids during gestation, an increased prevalence of spontaneous abortions, placental insufficiency, and cleft palate were found; it remains controversial whether a slight increase in risk of cleft palate pertains in humans . Chronic maternal ingestion of systemic glucocorticoids has been associated with lower birth weight and increased incidence of premature deliveries . In general, intravenous theophylline is not used during treatment of acute asthma exacerbations because of the lack of evidence of benefit . However, for patients who normally take theophylline, the medication is normally continued during the hospitalization. If the patient is unable to take oral medication, intravenous theophylline is usually substituted, but without a loading dose. Because toxicity can develop in the fetus when theophylline is administered at the time of delivery , serum levels should be closely followed and kept below 15 mg per mL. In patients with severe bronchoconstriction, who are refractory to inhaled nebulized albuterol sulfate, parenteral agents such as terbutaline sulfate, 0. A major concern is that epinephrine may cause uterine artery vasoconstriction through its α-adrenergic effects; this potential risk would have to be balanced against the need to reverse refractory bronchoconstriction . Early intervention with noninvasive ventilation and/or intubation with ventilatory support should be seriously considered . For patients who are extremely difficult to manage even with therapeutic levels of bronchodilators, high-dose glucocorticoids, and mechanical ventilation, a few less-studied therapeutic interventions such as intravenous magnesium sulfate and inhaled isoflurane  can be considered. None of these interventions have been studied in pregnancy, so their use should be limited to situations in which the woman’s life is in danger and all other forms of therapy have failed (see Chapter 172, for a full discussion). There have been anecdotal reports of significant maternal improvement after delivery of the fetus . The decision for urgent delivery is complicated and depends in part on the gestational age of the fetus and the clinical status of the mother . Pneumomediastinum and Pneumothorax the natural history of pneumomediastinum is spontaneous resolution within 3 to 14 days without permanent sequelae. Pneumomediastinum does not usually require drainage in adults because the air usually dissects out of the mediastinum into the subcutaneous tissues of the neck. Thus, treatment should be directed at improving any underlying predisposing cause, such as asthma, if present. A spontaneous pneumothorax occupying less than 20% of the hemithorax in an asymptomatic patient not on mechanical ventilation can be monitored closely without immediate insertion of a chest tube. In patients who are symptomatic, on mechanical ventilation, or have an enlarging pneumothorax, chest tube placement is mandatory. Patients whose pneumothorax develops as a complication of barotrauma during mechanical ventilation may also require adjustments in the ventilator settings to reduce airway pressures and further barotrauma. Patients with an existing pneumothorax or history of one in the past are at increased risk of worsening or recurrence of pneumothorax during labor and delivery, particularly during the Valsalva maneuvers at parturition. Although formal evidence is lacking, use of epidural analgesia and assisted vaginal delivery is suggested to avoid prolonged Valsalva maneuvers . For patients requiring cesarean section, analgesia with epidural anesthetic is preferred to general anesthesia with positive pressure ventilation. The recurrence rate of ipsilateral spontaneous pneumothorax is 30% to 50% within 5 years without pleurodesis . Pleurodesis with any tetracycline derivative through a chest tube is contraindicated in pregnancy because of possible fetal exposure. Patients who are receiving ongoing warfarin therapy for prior thromboembolic disease should be changed to subcutaneous heparin therapy before conception or at least before the sixth week of pregnancy. Pregnant women with a history of thromboembolic disease and/or hypercoagulable state should receive thromboembolic prophylaxis throughout pregnancy and for 4 to 6 weeks postpartum . Once adequate hemostasis has been accomplished postpartum, subcutaneous anticoagulation therapy can be resumed and continued until 6 weeks postpartum. Alternatively, warfarin can be added to subcutaneous heparin, and the heparin stopped when therapeutic prolongation of the International Normalized Ratio is achieved. Aspiration of Gastric Contents Based on national surveys of obstetric practice, antacid administration, H blockade, or proton pump inhibitors have been used for aspiration2 prophylaxis in pregnant women who require general anesthesia or analgesic therapy other than local or epidural anesthetics . This should probably be individualized, in view of the low risk of aspiration during spontaneous vaginal delivery in nonsedated patients and the small proportion of patients who require emergent general anesthesia. The Advisory Committee on Immunization Practices currently recommends the administration of the inactivated influenza vaccine for all pregnant women and also the intranasal flu vaccine should not be given to pregnant women because it contains a live-attenuated virus . The parenteral influenza vaccine contains inactivated virus and is not associated with adverse pregnancy outcomes. Maternal vaccination will also protect newborn infants from influenza, which is important as infants <6 months are at increased risk of influenza- associated complications and are not eligible to receive influenza vaccination. In addition, influenza vaccination is recommended for all women who will be pregnant during the influenza season and should be administered between October and mid-November regardless of the trimester of pregnancy . If a β-adrenergic tocolytic agent must be used, limiting the intravenous phase of β-adrenergic therapy to less than 24 to 48 hours and adjusting the dose to keep the maternal heart rate under 120 beats per minute may reduce complications. The β-adrenergic agent should be discontinued immediately at the earliest sign of respiratory distress, such as chest pain, tachypnea, dyspnea, or reduced oxygen saturation. Careful fluid balance records should be maintained, and fluid restriction and, possibly, diuresis should be considered when intake exceeds output by greater than 500 mL.
It is also unknown if medical air buy genuine disulfiram, used as placebo in these studies buy cheap disulfiram 500mg on line, could have exerted a therapeutic effect by cooling the nasal mucosa discount 250 mg disulfiram with amex, for example. Until new evidence is available, we suggest considering the use of oxygen in patients with respiratory distress because it is a low-risk intervention with potential benefits. Furthermore, nausea and vomiting may hinder reaching nutritional goals by delaying initiation of enteral feeding and complicate medication delivery and absorption. Constipation Constipation is defined as infrequent or absent bowel movements that occur with difficulty of passing stool. Vasoactive drugs such as dopamine can cause constipation, and hemodynamic instability in the setting of hypoperfusion, shock, and endotoxin overproduction can decrease bowel motility. Opioids are regularly used for management of pain and sedation among critically ill patients and frequently cause constipation. Assessment It is important to elicit a careful history, including the past medical history, the past abdominal surgical history, and prior bowel habits to establish whether chronic constipation was present or the patient has risk factors for constipation. Inpatient medications and medical interventions performed during the hospitalization must also be reviewed. The timing, quality, quantity, and frequency of stools since admission will characterize the degree of constipation. The abdominal examination may show firmness, distension, and the presence of hyperactive or hypoactive bowel sounds. In some cases, fecal impaction may present as diarrhea with incontinence when fecal material higher in the colon is broken down into liquid form and flows past the mass. Patients with traumatic spinal cord injury often have neurogenic bowel, but clinicians may overlook it in nontraumatic etiologies such as multiple sclerosis, stroke, or cancer. In these patients, digital rectal and abdominal exams can help distinguish between upper motor neuron (a tight anal sphincter with peristalsis intact) and lower motor neuron lesions (a flaccid sphincter with no volitional contraction). In upper motor neuron injury, evacuation depends on stimulating the bowel wall digitally or with a suppository; by comparison, patients with lower motor neuron injury may need stool-bulking agents like fiber to control stool flow . A plain abdominal radiograph can estimate the stool burden and differentiate between obstruction and constipation. In patients with continued symptoms and concern of alternative etiologies, computed tomography may aid in evaluation of small bowel obstruction, ileus, intra-abdominal abscess, bowel perforation or undiagnosed intraluminal or extraluminal abdominal masses. Treatments It can be effective to time medication use with a patient’s normal toileting schedule and take advantage of the gastrocolonic response with meals to improve outcomes. Hydration and high dietary fiber content are advantageous for healthy, active patients; however, additional dietary fiber such as psyllium may worsen constipation and should generally be avoided for critically ill patients who are not well hydrated. If constipation due to secondary causes is suspected, interventions aimed at treating and reversing underlying etiologies should be attempted. Pharmacologic therapies that utilize different mechanisms and combine oral and rectal interventions may yield effective results. The early use of supportive therapeutic agents is important and can be initiated independent of underlying pathology and bowel habits (see Table 35. Magnesium salts must be used cautiously in renal insufficiency as this may lead to magnesium toxicity. Lactulose passes unabsorbed into the colon where bacteria break it down, thus possibly causing bloating and abdominal cramping. Sodium phosphate enemas should be used with caution among elderly patients as they may cause hypotension, volume depletion, and electrolyte loss . Metoclopramide is a prokinetic agent that antagonizes dopamine receptors, and it can be used in constipation that has not responded to other pharmacologic interventions. Methylnaltrexone is a peripheral opioid antagonist with limited ability to cross the blood–brain barrier and thus does not reverse centrally mediated analgesia. It is approved for treatment of opioid-induced constipation among patients with advanced illness and is effective for inducing laxation of palliative care patients with opioid-induced constipation where conventional laxatives have failed . Nausea is a subjective sensation that precedes the need to vomit and may be associated with other symptoms including tachycardia, lightheadedness, diaphoresis, abdominal pain, and diarrhea. Retching is contraction of the abdominal musculature in the presence of a closed glottis and no expulsion of gastric contents. Any of these symptoms in the most severe form may result in electrolytes imbalances, dehydration, and feeding intolerance with subsequent malnutrition. The vomiting center additionally activates efferent pathways to the cranial nerves, diaphragm, and abdominal muscles [26,27]. Secondary causes of symptoms are adverse effects from medications, shock, abnormal lab values, renal failure, intracranial lesions, increased intracranial pressure, heart failure, and nonabdominal surgery . Assessment Evaluation of nausea and vomiting in the critical care setting must involve patient assessment and corroboration of information from nursing staff. A thorough evaluation of the history, physical examination, laboratory, and radiographic data can frequently identify an etiology. Key components to assess are as follows: Symptoms of nausea, vomiting, retching, reflux, diarrhea, distension, abdominal pain, regurgitation, and constipation Timing, frequency, nature of the event (i. Bilious or fecal emesis associated with abdominal discomfort and constipation or absence of bowel movements can suggest bowel obstruction. Ileus occurs after abdominal surgery, and general anesthesia also contributes to nausea among postoperative patients. Treatment A successful approach to managing the symptomatic patient incorporates thorough patient assessment, knowledge of the emetic pathophysiologic pathways, and a comprehensive treatment plan including pharmacologic and emotional support . Published guidelines currently focus on chemotherapy-related and postoperative nausea management [27,28]. The occurrence of encephalopathy during critical illness may result in clinicians treating signs of emesis rather than symptoms. Although targeted antiemetic treatment blocks the neurotransmitters implicated in the underlying cause, empiric therapy may be necessary without a clear etiology, usually with a dopamine or serotonin antagonist . Phenothiazines are D antagonists but have broader activity than do2 metoclopramide, as they additionally block cholinergic and histamine receptors. These drugs have potent antiemetic activity, but are frequently associated with adverse effects including hypotension, sedation, dry mouth, and extrapyramidal effects. Prochlorperazine, promethazine, chlorpromazine, and levomepromazine are several phenothiazines that are available. Among terminal cancer patients, it is commonly used for the management of nausea and vomiting, and it has also been used for postoperative nausea and vomiting . More recently, there has been interest in the atypical antipsychotic olanzapine for chronic nausea and chemotherapy-induced nausea and vomiting.