Surgical Critical Care and Emergency Surgery. Группа авторов

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Название Surgical Critical Care and Emergency Surgery
Автор произведения Группа авторов
Жанр Медицина
Серия
Издательство Медицина
Год выпуска 0
isbn 9781119756774



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epidural analgesia.Neuraxial analgesia (NA) has no effect on the surgical stress response. NA does not affect oxygen consumption, vasopressin, catecholamine, cortisol, or glucose levels.Thoracic epidural catheters above T4 level are safe and unlikely to cause cardiovascular effects.All of the choices are false regarding thoracic epidural catheters except choice A. Pulmonary function is unaffected by thoracic epidural analgesia in patients with normal function. However, severe pulmonary disease is a relative contraindication for brachial plexus blocks. Brachial plexus blocks such as an interscalene block affect ipsilateral hemi‐diaphragmatic excursion and reduce functional residual capacity and pulmonary function as much as 40%. Interestingly, the recurrent laryngeal nerve may also be blocked and can cause complete airway obstruction in a patient with existing vocal cord palsy. A blockade at the T5‐L1 level will increase gastric secretions, peristalsis, and enhanced gastric motility due to increased parasympathetic activity and sympathetic splanchnic blockade making choice B incorrect answer. Renal blood flow is auto‐regulated and unaffected by epidural analgesia. When thoracic epidural catheters are used, indwelling urinary catheters are not always required. Lumbar epidural analgesia however, can cause urinary retention, especially when blocking S2 to S4 spinal segments. Therefore, lumbar epidural catheters are more likely to affect bladder function than thoracic epidurals (choice C). One of the major benefits when choosing neuraxial analgesia (NA) is to blunt the sympathetic stress response. NA reduces oxygen consumption and decreases levels of vasopressin, catecholamines, cortisol, and glucose (choice D). Choice E is incorrect, because blocks at the T1‐4 level result in sympathetic blockade and profound cardiovascular effects. Blocks at T1‐T4 result in hypotension from both bradycardia and decreased cardiac contractility.Answer: AMian A, Chaudhry I, Huang R, Rizk E, Tubbs RS, Loukas M. Brachial plexus anesthesia: A review of the relevant anatomy, complications, and anatomical variations. Clin Anat. 2014; 27(2):210–21.Basse L, Werner M, Kehlet H. Is urinary drainage necessary during continuous epidural analgesia after colonic resection? Reg Anesth Pain Med. 2000; 25(5):498–501.

      2 A 45‐year‐old man is admitted to the ICU with pneumonia, fever, agitation, and confusion. He acutely becomes increasingly agitated and is treated with haloperidol. His vital signs are respiratory rate of 18/min, oxygen saturation 94%, heart rate 92/min, blood pressure 154/78 mmHg, and temperature 38.9 °C. He is sweating, drooling with painful contractions of the neck, and is salivating. Which of the following medications is the treatment of choice? Benztropine (Cogentin)Lorazepam (Ativan)Metoclopramide (Reglan)Dantrolene (Ryanodex)Quetiapine (Seroquel)The patient is exhibiting signs of a dystonic reaction and his symptoms are best treated with benztropine. Dystonic reactions are an unwanted effect after administration of neuroleptic medications. Dystonic reactions can occur immediately, or be delayed hours to days. Classic features of dystonic reaction to medications such as haloperidol are cholinergic symptoms such as increased salivation and spasmodic or sustained involuntary contractions of muscles in the face, neck, trunk, pelvis, extremities, or larynx. Dystonic reactions, while not usually life threatening, are distressing for patients and families. Benztropine, an anticholinergic agent, is used for symptomatic improvement (choice A). While some symptoms can be improved with benzodiazepines, this class of medication may worsen his confusion, blunt his respiratory drive, and contribute to ICU delirium, so choice B is not the best answer. Metoclopramide (Reglan) exerts an antiemetic effect by antagonist activity at central D2 receptors in the chemoreceptor trigger zone and may potentiate the dyskinesia symptoms, so choice C is incorrect. Dantrolene (Ryanodex) is used in reversal of malignant hyperthermia and has no primary role in treatment of dystonic reactions (choice D). While haloperidol (Haldol) is associated with neuroleptic malignant syndrome, the side effects manifested is mental status change in the form of agitated delirium with confusion or catatonic signs and mutism. Other symptoms include muscular rigidity which can be demonstrated by moving the extremities and is characterized by “lead pipe rigidity” or stable resistance through all ranges of movement. Hypothermia is common and extremely high temperatures greater than 40 °C is common. Autonomic dysfunction in the form of tachycardia with hypertension and tachypnea along with dysrhythmias may occur. In the scenarios of induced neuroleptic malignant syndrome, dantrolene can be an antidote. Quetiapine (Seroquel) is a second‐generation antipsychotic and known to be rare in causing extrapyramidal side effects and has no role in treatment of dystonic side effects (choice E).Answer: ADigby G, Jalini S, Taylor S. Medication‐induced acute dystonic reaction: the challenge of diagnosing movement disorders in the intensive care unit. BMJ Case Resp. 2015; 2015:bcr2014207215Goff DC, Arana GW, Greenblatt DJ, Dupont R, Ornsteen M, Harmatz JS, Shader RI. The effect of benztropine on haloperidol‐induced dystonia, clinical efficacy and pharmacokinetics: a prospective, double‐blind trial. J Clin Psychopharmacol 1991; 11(2):106–12.

      3 A 75‐year‐old woman underwent a cholecystectomy for a gangrenous gallbladder. Postoperatively, the patient appears calm and you would like to extubate the patient in the next 24 hours. Which of the following represents the best stepwise approach to pain and sedation?Short‐acting narcotic infusion with fentanyl and propofol.Standing IV acetaminophen (Ofirmev), low‐dose ketamine (Ketalar) infusion, and PRN hydromorphone (Dilaudid) IV push.Short‐acting narcotic infusion with fentanyl, plus dexmedetomidine (Precedex) drip plus gabapentin (Neurontin) PO.Short‐acting remifentanil and propofol infusions.Propofol infusion and dexmedetomidine (Precedex).Narcotic first regimens are common but undesirable because their adverse effects include ileus, delayed extubation, tolerance, and opioid‐induced hyperalgesia. Narcotics also place patients at risk for withdrawal. For most patients, especially those you plan to extubate soon or those at risk for complications, narcotic infusions are not the first choice. A stepwise approach including multimodal analgesia with acetaminophen, intermittently dosed narcotics and ketamine (0.5 mg/kg IVP × 1 followed by 1–2 mcg/kg/min infusion) is recommended. The goal is to minimize opioid therapy when managing postsurgical adult patients in the ICU (conditional recommendation, very low quality of evidence) and ketamine can be used as an IV adjunct. Gabapentin is also available as part of stepwise approach. Acetaminophen and pain‐dose ketamine infusions are excellent analgesics and can be added to an intermittently dosed narcotic plan as needed, making choice B the best answer. Choices A, C, and D are also incorrect because they rely on opioid infusions and do not represent the best stepwise approach. It is especially important to avoid continuous narcotic infusions in patients at high risk for opioid toxicity, such as those with sleep apnea or at patients at risk for ileus. Although dexmedetomidine (Precedex) has some pain effects as an alpha 2 agonist, its primary effect is sedation and would not be the best choice for pain in combination with propofol. The patient is calm and does not need two sedative agents, so choice (E) is also incorrect.Answer: BDevlin JW, Skrobik Y, Gélinas C, Needham DM, Slooter AJC, Pandharipande PP, Watson PL, Weinhouse GL, Nunnally ME, Rochwerg B, Balas MC, van den Boogaard M, Bosma KJ, Brummel NE, Chanques G, Denehy L, Drouot X, Fraser GL, Harris JE, Joffe AM, Kho ME, Kress JP, Lanphere JA, McKinley S, Neufeld KJ, Pisani MA, Payen JF, Pun BT, Puntillo KA, Riker RR, Robinson BRH, Shehabi Y, Szumita PM, Winkelman C, Centofanti JE, Price C, Nikayin S, Misak CJ, Flood PD, Kiedrowski K, Alhazzani W. Clinical practice guidelines for the prevention and management of pain, agitation/sedation, delirium, immobility, and sleep disruption in adult patients in the ICU. Crit Care Med. 2018; 46(9):e825–73.

      4 A 67‐year‐old woman is in the ICU on postoperative day 2 after laparotomy. Current medications include clonidine, quetiapine, hydromorphone, melatonin, and metoprolol. Her sleep pattern is altered and she shows signs of agitated delirium. Which of her medications increases her risk for aspiration?ClonidineDexmedetomidine (Precedex)Quetiapine (Seroquel)Hydromorphone (Dilaudid)Melatonin (N‐acetyl‐5‐hydroxytryptamine)Antipsychotic medications such as haloperidol and quetiapine are used to manage delirium. These medications can increase the QTC interval but also antagonize dopamine signaling, which affects the swallow mechanism and increases the risk of aspiration. Therefore, choice C is correct.Both clonidine (choice A) and dexmedetomidine (choice B) are useful adjuncts in pain management because of their effects at central α2 receptors. Clonidine blocks sympathetic outflow, reduces arterial blood pressure, and ameliorates symptoms of alcohol and opiate withdrawal but does not increase aspiration risk. When used in epidural pain catheters, clonidine produces analgesia at the presynaptic and post junctional alpha 2 receptors. Dexmedetomidine (Precedex) produces centrally mediated sympatholytic sedation, anxiolysis, and analgesia. A transient increase in blood pressure during the loading dose of dexmedetomidine may occur, followed by hypotension which may be