AMBULATORY SURGERY 门诊手术麻醉
Laurence M. Hausman, MD
James N. Koppel, MD
A 38-year-old woman is scheduled for an ambulatory diagnostic pelvic laparoscopy at 3 o’clock in the afternoon. She arrives 1 hour before scheduled surgery with her 11-year-old son and appears to be extremely apprehensive. Prior medical history is significant for asymptomatic esophageal reflux, long-standing stable asthma that has been successfully treated with inhaled sympathomimetics and steroids, and juvenile-onset diabetes mellitus, currently controlled with 25 U neutral protamine Hagedorn (NPH) and 6 U regular insulin every morning and 10 U NPH and 3 U regular insulin every night.
一个38岁妇女安排下午3点做盆腔镜诊断性检查术。术前1小时和11岁的儿子一起到了，但是看起来非常不安。先前的病史显示她有明显的无症状性食管返流，哮喘经过吸入拟交感神经药物和甾体类激素治疗处于长期稳定状态，青少年型糖尿病用25U低精蛋白锌胰岛素（NPH）和每天早上6U常规胰岛素，夜里10UNPH和3U常规胰岛素控制。
QUESTIONS
1.Are there advantages to performing surgery on an ambulatory basis?
2.Which patients are considered acceptable candidates for ambulatory surgery?
3.Are there any patients who should never have surgery on an ambulatory basis?
4.Are diabetic patients suitable candidates for ambulatory surgery?
5.What types of surgical procedures are appropriate for ambulatory surgery?
6.What is the appropriate fasting time before ambulatory surgery that necessitates an anesthetic?
7.Should drugs be administered to empty the stomach or change gastric acidity or volume before the administration of an anesthetic?
8.How can patients be appropriately screened for anesthesia when ambulatory surgery is planned?
9.What preoperative laboratory studies should be obtained before surgery?
10.Should an internist evaluate each patient before ambulatory surgery?
11.Is anxiolytic premedication advisable before ambulatory surgery, and what agents are appropriate?
12.What are the reasons for last-minute cancellation or postponement of surgery?
13.What is the ideal anesthetic for ambulatory surgery?
14.Are there relative or absolute contraindications to the administration of a general anesthetic in the ambulatory setting?
15.What are the advantages and disadvantages to performing a conduction anesthetic in the ambulatory patient?
16.What are the advantages and disadvantages of selecting a nerve block technique for the ambulatory patient?
17.Describe the intravenous regional anesthetic technique (Bier block) for surgery on the extremities.
18.What sedatives can be administered to supplement a regional anesthetic?
19.What complications of nerve block anesthesia are of special concern to the ambulatory patient?
20.Should patients having ambulatory surgery be tracheally intubated?
21.What is the role of propofol in ambulatory surgery?
22.What is total intravenous anesthesia (TIVA), and what are its advantages and disadvantages?
23.What is moderate sedation, when is it employed, and what advantages does it offer?
24.When tracheal intubation is required for a short procedure, can one avoid the myalgias associated with succinylcholine?
25.Can a relative overdose of benzodiazepines be safely antagonized?
26.Do the newer volatile agents offer advantages over enflurane and isoflurane?
27.What are the etiologies of nausea and vomiting, and what measures can be taken to decrease their incidence and severity?
28.How is pain best controlled in the ambulatory patient in the postanesthesia care unit (PACU)?
29.What discharge criteria must be met before a patient may leave the ambulatory surgery center?
30. What are the causes of unexpected hospitalization following ambulatory surgery?
31.When may patients operate a motor vehicle after receiving a general anesthetic?
32.What is the role of aftercare centers for the ambulatory surgery patient?
33.Are quality assurance and continuous quality improvement possible for ambulatory
1. 在门诊手术的优点在哪里？
2. 哪些病人可以接受门诊手术？
3. 哪些病人一定不能在门诊进行手术？
4. 糖尿病人适合门诊手术吗？
5. 门诊手术包括的种类有哪些？
6. 门诊手术麻醉合适的禁食时间是多少？
7. 麻醉前是否使用药物促进胃排空，改变胃液酸度和胃液量？
8. 怎么适当拒绝对已经安排门诊手术的病人进行麻醉？
9. 术前需要知道那些实验室检查结果？
10. 每个门诊手术病人都要进行内科评估吗？
11. 门诊手术前建议给抗焦虑药吗？哪些药物合适呢？
12. 最后一次取消或推迟手术的原因？
13. 什么是门诊手术的理想麻醉？
14. 有没有门诊手术全麻的相对或绝对禁忌证？
15. 对门诊手术施行部位麻醉的优缺点？
16. 对门诊手术选择神经阻滞的优缺点？
17. 描述四肢手术的静脉区域麻醉技术。
18. 哪些镇静药可以强化区域麻醉？
19. 门诊手术进行神经阻滞麻醉需要特别关注的并发症是什么？
20. 门诊麻醉需要气管插管吗？
21. 异丙酚在门诊麻醉的地位？
22. 什么是全静脉麻醉（TIVA），优缺点是什么？
23. 什么是适度镇静，给药时机和镇静的优点是什么？
24. 短小手术何时需要气管插管，能避免司可林相关的术后肌痛吗？
25. 相对大剂量的地西泮能被安全拮抗吗？
26. 新型挥发性麻醉药相对于安氟醚和异氟醚优越吗？
27. 恶心、呕吐的病因学是什么？哪些措施可以减少发生率和降低发作程度？
28. 怎么使门诊手术病人在麻醉后恢复室（PACU）得到最好的镇痛？
29. 病人离开门诊手术中心必需达到的标准是什么？
30. 门诊手术后意外住院的病人怎么处理？
31. 全麻后的病人何时能进行机动车驾驶？
32. 门诊手术病人术后服务中心的地位是什么？
33. 门诊手术安全吗？质量能持续提高吗？
1.Are there advantages to performing surgery on an ambulatory basis?
There are multiple advantages to performing surgery on an ambulatory basis. Most obviously, the patient returns much more quickly to the familiar home environment. This is especially important for both pediatric and geriatric surgical patients. Formerly, patients might have remained hospitalized for days, rather than a few hours. A reduction in the acquisition of nosocomial infections has also been noted. This is an extremely important consideration when dealing with immunocompromised patients such as organ transplant recipients or patients who are receiving chemotherapeutic agents. Furthermore, in the ambulatory model, the incidence of medication errors related to either faulty prescribing or dispensing of drugs has decreased. In addition, overall costs are usually significantly reduced. This cost saving is due in part to a decrease in the number of laboratory tests requested and medical consultations obtained, as well as pharmaceuticals dispensed. Of course, the significant expense of both the inpatient hospitalization as well as the hospital facility fee is avoided. Other less tangible advantages include ease of scheduling procedures, without having to consider variables such as operating room block time, and an improved sense of patient privacy. This occurs because most offices are staffed by a small consistent group of personnel.
As a group, ambulatory patients tend to be more aware of the effects of the anesthetic they receive than the inpatient population. Because ambulatory patients usually undergo less intrusive surgical procedures and are less ill postoperatively, an attempt is made to resume usual preoperative activities at an earlier time. Therefore, nausea, vomiting, myalgias, headache, as well as disordered sensorium and vertigo may appear to be more significant to this group of patients. Unpleasant symptoms are spontaneously reported with greater frequency than in the inpatient group, and patients may tend to focus their attention on them. These discomforting symptoms, if present postoperatively, may be recalled in a vivid fashion if an additional surgical procedure is required. The negative recall may predispose the patient to extreme anxiety.
Only a small subgroup of patients may actually prefer hospitalization to ambulatory surgery.
1. 在门诊手术的优点在哪里？
门诊手术有很多优点。首先，病人可以尽快地回到熟悉的家庭环境。这对小儿和老年病人特别重要。以前病人需要在医院呆几天而不是几个小时。减少院内感染也得到了关注。这对免疫耐受的病人如器官移植和接受化疗的病人尤其重要。而其在门诊模式下，因开错药和发错药造成错误给药的机率也降低。另外，花费也显著降低。部分原因是降低了要求的实验室检查的数量，医疗咨询费用和给药费用。住院病人治疗费和医院相关设施费用支出也得到避免。其他的包括简化手续，不必考虑手术等待时间，保护病人隐私。因为门诊手术只是一个小的团队。
作为一个群体，门诊手术病人比住院病人更加关注麻醉效果，因为门诊病人大多进行的是创伤较小，术后并发症较少的操作，他们试图尽早恢复到术前的活动状态。因此，恶心、呕吐、肌痛、头痛及意识错乱、眩晕的发生率更加显著，他们发生不愉快症状自发报告的机率也较住院病人显著频繁，这些不适症状如果在术后发生，当在需要进行另外手术时会被回忆的栩栩如生，这些回忆可能造成病人额外的焦虑。
只有很小一部分病人选择住院来接受门诊手术，
2.Which patients are considered acceptable candidates for ambulatory surgery?
For patients to be considered acceptable candidates for ambulatory surgery, generally they should have a relatively stable medical condition. However, many centers now routinely accept American Society of Anesthesiologists (ASA) physical status III and IV patients for selected, relatively noninvasive surgical procedures or diagnostic studies. Generally, less invasive surgery is performed on patients who are less healthy, while more invasive surgery is performed only on ASA physical status I or II patients. Patients with cardiovascular disease have an increased risk of perioperative complications. Those with severe physical or mental handicaps are often excluded from consideration as candidates for ambulatory surgery. The ability to comprehend and comply with postoperative instructions is mandatory to the success of ambulatory surgery.
Ambulatory surgery is well suited for the pediatric patient population. Generally, ambulatory surgical procedures commonly performed on children are shorter in duration, less extensive, and less invasive than the majority of procedures performed on adults. Additional benefits to the pediatric group include less disruption of the child’s normal feeding schedule and decreased separation time from parents. Exposure to the unfamiliar and frightening hospital milieu can be reduced to the bare minimum. Additionally, because recovery times are short for procedures such as myringotomy and tubes, circumcision, and inguinal herniorrhaphy, early discharge from the facility is feasible.
Preoperative communication and collaboration between anesthesiologists and their surgical colleagues are essential in the case of the questionable or problem patient. The surgeon who is to perform the procedure, the patient, and the family must be agreeable to the concept of ambulatory surgery. However, reimbursement schedules created by insurance carriers will often convince the occasional skeptic, because costs associated with hospitalization for procedures that can be readily performed on an ambulatory basis will usually not be covered. Overwhelming and incontrovertible evidence of medical necessity for inpatient care must be presented to obtain authorization for postoperative hospitalization.
2. 哪些病人被认为可以接受门诊手术？
对认为可以接受门诊手术的病人，一般认为需要有相对稳定的医疗状况。事实上，很多中心常规接受ASA III-IV级的病人接受相对无创或诊断性检查。一般健康条件差的病人进行创伤小的操作，而只对ASA I – II级病人施行较大创伤的手术。伴有心血管疾病的可以增加围术期并发症。那些有身体或精神残疾的病人通常被排除在考虑之外。判断预后的综合能力是门诊手术成功的关键。
门诊手术很适合儿科病人，一般，门诊手术适于相对于成人大手术时间短，范围小，创伤少的小手术。其他的包括尽量减少对儿童的进食时间的干扰，缩短和父母分开的时间，使暴露在不熟悉的和令人惊怕的医院环境中的时间减少到最小。恢复时间短的手术如鼓膜切开与置管术，包皮环切术和腹股沟疝修补术早期离开医院都是可行的。
对一些有疑问的或有问题的病人术前麻醉医生和外科同事的交流是必要的。手术医生、病人和病人家属都必须同意进行门诊手术。事实上保险公司制定的赔偿计划要说明可能发生的意外，因为住院消费将会得到更好门诊手术的还没有消除。需要术后住院治疗的证据必须明白无误地提出来并得到批准进行术后住院治疗。作者: 华西小卒 时间: 2010-8-15 13:23
3.Are there any patients who should never have surgery on an ambulatory basis?
An exception to the list of acceptable candidates is ex-preterm infants who are less than 55–60 weeks postconceptual age. These patients may have life-threatening episodes of postoperative apnea and bradycardia as many as 12 hours and up to 48 hours after receiving a general anesthetic. Therefore, in-hospital monitoring of these patients is recommended. For similar reasons, term infants less than 44 weeks postconceptual age should also have surgery performed only on an inpatient basis. Postoperative respiratory monitoring is mandatory for at least 12–18 hours. If at all possible, any required surgery or diagnostic procedures requiring the administration of either a sedative or a general anesthetic should be postponed until the child passes this period.
3.哪些病人一定不能在门诊进行手术？
在以上可以接受门诊手术列表病人中，年龄低于55-60周的新生早产儿除外。这些病人存在全麻后12-48小时出现致命性呼吸暂停和心动过缓的危险。因此对这些对病推荐进行院内监护。相同的原因，低于44周的足月新生儿只在住院后进行手术，并且术后必须进行12-18小时的呼吸监护。如果可能任何需要给镇今年给药物或全麻的手术或诊断性检查均应推迟过这个时期。
4.Are diabetic patients suitable candidates for ambulatory surgery?
Diabetic patients may present a major challenge for the anesthesiologist when scheduled for ambulatory surgery. Because of the critical nature of glucose homeostasis, it may be advisable to handle exceptionally brittle diabetics on an inpatient basis. Preoperatively, diabetic patients must be carefully assessed for the presence of end-organ damage. Cardiovascular disease, autonomic and renal insufficiency, and gastroparesis may lead to potential problems in the perioperative period.
It is preferable to schedule surgery on the insulin-dependent diabetic as the first or second case of the day. The major concerns, of course, are to avoid the extremes of plasma glucose, both hypoglycemia and hyperglycemia, as well as acidosis. Delays in insulin administration may lead to ketoacidosis despite the fasting state. For this reason, it is recommended that patients receive insulin along with a continuous infusion of dextrose on arrival at the ambulatory surgery facility. Insulin may be administered by either the subcutaneous or intravenous route. The relative advantage, if any, of administering a continuous infusion of regular insulin versus one third to one half of the usual long-acting insulin dose subcutaneously has not been demonstrated. Another option for early-morning surgical procedures is to administer the usual long-acting insulin dose subcutaneously immediately following surgery and shift the time of all meals and future insulin injections by the same offset.
Non-insulin-dependent diabetics who are controlled by one of the available oral hypoglycemic agents must also be carefully monitored in the perioperative period by periodic fingerstick or blood glucose determinations. The half-life of some of the oral agents may be as long as 60 hours (chlorpropamide). Fortunately, patients with adult-onset, non-insulin-dependent diabetes mellitus (NIDDM) rarely develop ketoacidosis. However, this group may develop hyperosmolar, nonketotic coma when significant hyperglycemia and dehydration occur.
Before discharge, it is critical that diabetic patients be capable of eating and be relatively free of significant nausea that might lead to emesis and inability to maintain adequate caloric intake.
4.糖尿病人适合门诊手术吗？
糖尿病人安排做门诊手术对麻醉医生来说是一个重大的挑战。因为糖稳态的特性，掌握住院病人突然出现的糖尿病处理是需要的，糖尿病人终末器官的损害要被仔细评估。心血管疾病，自律性差和肾功能不全，轻度胃瘫都导致围术期潜在的问题发生。
优先安排胰岛素依赖的糖尿病人在当天的第一或第二台进行手术，主要的原因是避免高血糖，低血糖和酸中毒的发生。没有及时给胰岛素即使是在禁食状态下也会导致酮症酸中毒的发生。因为这个原因，推荐病人到达门诊手术中心后，葡萄糖和胰岛素一起给予。胰岛素皮下或静脉途径均可。持续输注普通胰岛素代替1/3-1/2长效皮下胰岛素的优点还没有得到证实。清早手术的另外一个选择是术后立即皮下给长效胰岛素，并且改变随后的所有进食和胰岛素注射的时间。
仅依靠口服一种降糖药控制血糖的非胰岛素依赖患者术前定期采用简易或实验室法监测血糖是必须的。有些口服降糖药的半衰期可达到60小时（氯磺丙脲）。幸运的是，非胰岛素依赖的糖尿病人很少发生酮症酸中毒，但血糖高时，这些病人可以有高渗性腹泻，非酮症昏迷和脱水。
离院前，糖尿病人能够进食，没有导致呕吐和不能摄入足够热量的恶心发生是非常重要的。
5.What types of surgical procedures are appropriate for ambulatory surgery?
Initially, it was believed that procedures should be limited to those that could be easily accomplished within 1–11/2 hours. This was based on the premise that recovery time would be significantly prolonged after the administration of a lengthy general anesthetic and would perhaps prevent discharge. However, it has been well demonstrated that patients may be discharged safely and on a timely basis even after long operations performed with general anesthesia.
The types of surgical procedures that may be performed on an ambulatory basis will depend on whether an ambulatory surgery facility is truly a freestanding unit (geographically detached from a hospital) or is located within a hospital, or directly contiguous to an inpatient facility. Hospital-based units often accept patients with a greater severity of baseline illness and may perform more complex surgical procedures for a number of reasons. In the event of an unexpected massive surgical hemorrhage, availability of immediate blood bank support is crucial. However, when the need for blood may be anticipated preoperatively, even freestanding ambulatory surgery centers can arrange for blood products to be available, and transfusions may be administered if the need arises. Patients may also be asked to donate one or more units of autologous blood, which may be kept available for either intraoperative or postoperative use. Procedures in which blood might be administered include extensive liposuction or reduction mammoplasty. Radiology services, as well as subspecialty consultative services and the relative ease of hospital transfer for overnight admission, allow performance of more involved and invasive procedures in hospital-based ambulatory surgical facilities.
Ideal procedures for ambulatory surgery result in relatively minor postoperative physiologic changes including fluid shifts and blood loss. Commonly performed surgeries include procedures from all surgical disciplines and subspecialties. A few examples include cataract extraction, minor breast surgery, plastic surgery, dilatation and curettage, hysteroscopy, termination of pregnancy, laparoscopy, arthroscopy, inguinal and umbilical herniorrhaphies. The common denominator of all the procedures is that they are associated with only mild-to-moderate degrees of postoperative pain, which may be readily controlled by oral analgesic agents.
In the early days of ambulatory surgery, tonsillectomy was an example of a procedure that was considered to require overnight in-hospital observation. Today, it is being performed on an ambulatory basis in many centers, although the period of postoperative observation is increased compared with that for other ambulatory surgeries. After tonsillectomy, nausea and vomiting are the most common complications causing morbidity. Early bleeding, if it occurs, usually becomes evident within the first 6 hours. Therefore, it is now considered safe to discharge individuals to home who are otherwise in good health and reside within a reasonable distance from the facility with responsible adults. It is especially important that adequate fluid repletion be accomplished before discharge because early attempts at fluid intake after tonsillectomy may be relatively unsuccessful as a result of marked pharyngeal pain.
5.门诊手术包括的种类有哪些？
可以进行的手术种类包括门诊手术设施是否是真正独立的（地理位置远离医院）或在院内，或直接和住院病人设施相连，有很多原因使院内门诊手术似可以接受比较严重疾病并能开展较复杂的手术。在意外发生大出血时，有可以立即应用的血库支持是非常重要的。实际上，何时需要用血术前应该可以预见，即使是独立的门诊手术也可以与被一些血制品可以使用，当需要时可以立即输血。也可以要求病人进行一个或多个单位的自体血储备，以备术中或术后使用。输血在大量吸脂术或乳房复位成形术也有可能用到。便捷的放射、咨询和转运到住院部过夜治疗，使得院内的门诊手术可以开展更大范围和侵入性操作。
理想的门诊手术是相对小的术后生理学变化，包括体液转移和失血。通常可以施行的手术包括各个学科和亚学科。如卡它性液体抽吸术，较小的乳腺手术，整形外科手术，刮宫术，宫腔镜检查术，终止妊娠，腹腔镜和关节镜检查术，腹股沟疝和脐疝修补术等。所有手术的通常标准是术后仅有轻到重度的疼痛，并且口服镇痛药可以很好控制的手术。
刚开展门诊手术的早期，扁桃体切除术被认为是需要住院过夜观察的例子之一。尽管术后观察的时间较其他门诊手术长，现在有很多中心开展了这种手术。扁桃体切除术后恶心、呕吐是致死的主要原因，早期有出血，通常术后6小时内较明显。因此现在认为让体格较好的病人，距离不远的和家里有负责人的父母的病人离院回家是安全的。离院前充分补液是重要的，因为咽痛早期经口流质摄入相对不安全。
6.What is the appropriate fasting time before ambulatory surgery that necessitates an anesthetic?
The prescribed preoperative fasting period for both fluids and solids for patients scheduled for ambulatory surgical procedures should be identical to that required for an inpatient who is scheduled to receive an anesthetic. The ASA have released guidelines that recommend 8 hours for solids, 6 hours for a light meal (toast and tea), 4 hours for breast milk, and 2 hours for clear liquids. Eight ounces of orange juice without pulp or coffee without milk has not been demonstrated to increase gastric volume. In fact, both resting gastric volume and acidity may be reduced, which may further decrease the incidence and potentially devastating sequelae of an intraoperative aspiration.
Other benefits result from decreasing the fasting time in preoperative patients. Patients allowed to drink clear fluids are more content while they impatiently wait for a surgical procedure that was either delayed or was scheduled for the latter hours of the day. Thirst is relieved, and hunger may be diminished. Furthermore, the ingestion of glucose-containing solutions may also prevent relative degrees of hypoglycemia noted in both healthy patients and those with limited reserves. It is important to emphasize that medications required for the maintenance of homeostasis such as blood pressure and cardiac drugs can be taken orally up to 1 hour before surgery with an ounce of water.
Fasting guidelines should not be made on a case-by-case basis but rather should be reflected in facility- or institution- wide guidelines.
6.门诊手术麻醉合适的禁食时间是多少？
术前禁食时间要靠接受麻醉的时间决定。ASA出版的指南是，推荐8小时禁固体食物，6小时禁易消化食物（土司和茶），4小时禁母乳，2小时禁清水。8盎司不带果肉的橙汁和不加牛奶的咖啡认为不增加胃容量。实际上，他们能使能增加潜在术中误吸的胃容量增加和胃酸都减少。
减少术前禁食时间的其他益处。当手术被推迟或当天晚些时候进行时，病人喝一些含有其他物质的清凉液体有助于减轻等待手术造成的不耐烦。口渴减轻，饥饿感消失。另外，含糖液体的摄入也可以阻止包括健康的和糖储备有限的病人发生低血糖的程度。需要强调的一点就是维持血压和心脏功能的药物可以在术前1小时用1盎司水口服。
接台手术不用给禁食指导，但是在设备简易的地方还是要重视或给予一个范围较宽的指南。
7.Should drugs be administered to empty the stomach or change gastric acidity or volume before the administration of an anesthetic?
Studies regarding differences in the resting gastric volume between the inpatient and ambulatory population have yielded conflicting results. Whereas some anesthesiologists administer liquid antacids before the induction of anesthesia, no evidence supports the notion that every patient must receive a soluble agent (0.3 molar sodium citrate, 30 ml). A soluble antacid is substituted for the conventional nonabsorbable antacid containing aluminum, magnesium, or calcium hydroxide to avoid the severe chemical pneumonitis that may result from aspiration of these particulate substances. Other pharmacologic agents include the H2-receptor blockers (ranitidine or famotidine), which inhibit gastric acid production and decrease gastric volume. Mental confusion has been reported after intravenous administration of cimetidine in geriatric patients. Ranitidine is more potent and specific and has a longer duration of action than cimetidine. Metoclopramide increases the tone of the lower esophageal sphincter as well as facilitating gastric emptying. However, it does not guarantee a stomach free of gastric contents. It also possesses anti-emetic properties. Metoclopramide, in conjunction with an H2-receptor blocker, may be more efficacious. However, the routine use of any of these drugs in patients without specific risk factors is not currently recommended.
Diabetes mellitus with evidence of autonomic dysfunction or gastric atony, documented hiatal hernia, a history of symptomatic gastroesophageal reflux, pregnancy, significant obesity, acute abdomen, or current opioid use or abuse are examples of diseases or conditions that appear to increase the incidence of aspiration during induction or emergence from general anesthesia or during heavy sedation. Therefore, prophylaxis in these situations is recommended. There is no advantage to administration of triple prophylaxis with H2-receptor antagonists, soluble antacids, and metoclopramide. If prophylaxis with an H2-blocker is employed, it should be given 1–2 hours preoperatively. Another effective regimen combines metoclopramide on the morning of surgery and a nonparticulate antacid immediately prior to surgery.
Despite the administration of pharmacologic agents and imposition of fasting, significant amounts of acidic gastric contents may still be present. Fortunately, aspiration of gastric material remains a relatively rare occurrence. If a patient is observed to aspirate and if symptoms of cough, wheeze, or hypoxemia while breathing room air do not develop within 2 hours, the development of significant respiratory sequelae is unlikely. Therefore, reliable and otherwise healthy ambulatory patients can probably be discharged after several hours of observation in the postanesthesia care area with the proviso that they immediately contact their physician at the onset of any symptoms.
7.麻醉前是否使用药物促进胃排空，改变胃液酸度和胃液量？
在住院病人和门诊病人不同研究得到的是相互矛盾的结果。然而，一些麻醉医生诱导前给予抗酸液体，没有证据支持每个病人必须给予易溶药物（0.3mmol柠檬酸钠,30ml）。可溶性抗酸药替代了传统的含铝、镁、氢氧化钙抗酸药，避免了这些颗粒的吸入产生严重化学性肺炎可能。其他一些药物包括H-2受体阻断剂（雷尼替丁或法莫替丁），可以抑制胃酸的分泌减少胃内容物。但是已经有报道老年病人静脉给予西咪替丁后有精神错乱的发生。雷尼替丁较西咪替丁有更强的效能，更高的特异性和更长的作用时间。胃复安促进胃排空的同时可以增加食道下端括约肌张力。但是它也不能保证胃内容物万无一失。也应给予抗呕吐药物。胃复安联合H-2受体阻断剂或许更有效。但是，当前不推荐对不存在特殊风险的每个病人常规使用。
有明确证据的胃自律性差或胃无力，明确资料显示的食道裂孔疝，胃食管返流史，怀孕，肥胖症，急腹症或当前正在使用和滥用阿片类都能增加诱导时，全麻时和深度镇静时无锡的发生率。因此推荐在这些情况下要预防发生。假如给H-2受体阻止剂，就要在术前的1-2小时给。另一个有效的措施是术晨使用胃复安联合术前立即使用非粒子类抗酸药。
尽管给予制酸药和禁食处理，一定数量的胃内酸性内容物是仍然存在的。幸运的是，误吸只是一个相对的发生率。如果病人被观察到有误吸，并且在呼吸室内空气时咳嗽、哮鸣音和低氧血症症状2小时内无进一步加重，发展为严重呼吸疾病的几率较小。因此，健康病人在麻醉后恢复室观察几个小时，并且在保证一旦发生任何症状将和他的医生立即联系后可以考虑让其出院。
8.How can patients be appropriately screened for anesthesia when ambulatory surgery is planned?
In the ideal situation, on the day before surgery a patient having an ambulatory procedure would have the opportunity to participate in a private conference with the anesthesiologist who will be caring for him or her. Rapport and trust could be established, and history and physical assessment could be conducted. Furthermore, appropriate laboratory tests could be ordered and additional consultations, if deemed necessary, could be requested. Finally, information from old medical records could be obtained.
To avoid an additional trip for the patient and family, some facilities may substitute a screening telephone interview for a personal interview, conducted by either a nurse or an anesthesiologist several days before surgery. Pertinent medical history can be elicited, general and specific instructions can be given, and reassurance offered to the patient. In this scenario, laboratory studies and additional components of the data base including an electrocardiogram (ECG) and radiographs, if necessary, are performed immediately before surgery. Previously established criteria will determine the tests that must be obtained. Of course, on the day of surgery the anesthesiologist must still review all information with the patient, conduct the appropriate examination, and obtain informed consent.
The surgeon who schedules surgery must assume a large degree of responsibility for the medical evaluation of the patient. The surgeon is often the only physician to see the patient until the day of surgery. Besides conducting a thorough history and physical examination, the surgeon may also request medical consultation when appropriate.
To aid in the screening process, surgeons may also selectively order laboratory and other examinations according to written guidelines established by the medical facility. However, a mechanism should be in place for free communication between the surgeon’s office and the facility so that appropriate action may be taken when abnormal laboratory values or other reports are received.
The anesthesiologist’s preoperative interview should be conducted in a relaxed, unhurried, and comprehensive manner both chronologically and geographically apart from the operating room. It is highly improper to conduct the preanesthesia interview and examination with the patient stripped of clothing and strapped to the operative room table. At this moment, the patient’s anxiety level may be extraordinarily high. Therefore, the patient may neglect to communicate essential information that may have an impact on either general medical care or intraoperative anesthetic management. Under these circumstances, it is truly impossible to obtain informed consent for anesthesia, which is a moral as well as a legal necessity. Additionally, with the surgeon and nurses waiting and instrumentation prepared, the pressure on the anesthesiologist to proceed with anesthesia may be intense.
The anesthesiologist should not fail to question patients firmly regarding the use of illicit drugs. In one patient population, one quarter of the subjects were found to have positive urine findings for commonly abused substances. Depending on the drug involved, modifications in patient management including cancellation of surgery might be well advised. Additionally, users of illicit drugs may have diminished capability or interest in complying with postoperative instructions.
8.怎么适当拒绝对已经安排门诊手术的病人进行麻醉？
理想的情况下，病人术前某天会有一个和他的麻醉医生会面的机会。进行沟通和建立信任，并进行病史和身体条件评估。另外还要开出一些实验室检查项目，如果认为有必要还可以对一些疑问进行咨询。最后从以往的医疗文件得到一些信息。
为了避免病人和家属的来回奔波，也可以用可视电话会面，可以由护士或麻醉医生在术前几天进行。这可以得到以前的医疗病史，也可以给出总的和特殊的指导以及一些安全承诺。这种方案下，如果觉得必要术前要可立即进行实验室检查和附加的资料库包括心电图（ECG），X光。之前的实验标准要得到。当然，手术当天麻醉医生要回顾所有的病人信息，作适当的检查，并得到病人的同意。
安排手术的医生必须对病人的医疗评估负起责任。通常直到术前一天手术医生是仅仅见过病人的唯一医生。除外完整的病史和体格检查，手术医生也担负起咨询的任务。
为了过程的完整，外科医生会按照医疗文书的指导进行一些实验室和其他的检查。实际上应该有建立一种机制，在当实验室和其他检查出现异常时，让病人和医生在医生办公室和手术室进行充分的交流。
麻醉医生术前访视应该在一个宽松的，放松的，关怀的环境中进行。病人脱光衣服在手术检查床进行麻醉访视和检查认为是非常不合适的。因此病人会忽视必要的交流，这将影响总体药物疗效和术中麻醉的管理。在这种环境中，真的不可能得到进行麻醉的同意，这在法律上也是正常的。另外，外科医生和护士的等待以及器械的准备对麻醉医生实施麻醉造成的压力也很大。
这种情况下，麻醉医生会漏问使用违禁药物的问题。病人中，有1/4会因为滥用普通药物而尿检呈阳性。依据使用的药物对病人作出适当的处理，包括建议取消手术。另外使用违禁药物的病人对术后指导的遵从度和执行的兴趣都减低。
9.What preoperative laboratory studies should be obtained before surgery?
For an ambulatory surgery unit that is affiliated with or attached to a hospital, clinical laboratory testing guidelines should be identical to those required by the related institution. It has been well established that shotgun, nonselective screening batteries of both laboratory, radiographic, and other studies yield an extraordinarily low rate of abnormal findings, few of which may have a significant impact on patient management. Patients scheduled for surgery should have preoperative testing ordered with selectivity and based only on a screening including a careful history and physical examination. In fact, indiscriminate ordering of tests can have potentially serious and deleterious consequences. To explain abnormal results, additional series of tests may be obtained. Some invasive studies have inherent dangers. Often, abnormalities are simply ignored, creating a potential medicolegal liability. Indiscriminate screening often reveals abnormalities that fail to have any relevance to either the surgery or the choice of anesthetic agent or technique. Some centers use handheld computers to obtain the patient history. Branching lines of questioning dependent on previous answers allow extensive information to be gathered. At the conclusion of the interactive interview, the computer can provide a detailed printout of significant findings in the history and recommend the preoperative testing to be obtained. Many facilities do not require any preoperative testing for superficial surgical procedures on otherwise healthy men and women below the age of 40–50 years.
9.术前需要知道那些实验室检查结果？
对于附属的或靠近医院的门诊手术室，要达到临床检查指导标准。他们建立了shotgun、一系列的实验室、放射学和其他检查异常情况漏诊的几率非常小，几乎不会影响到对病人的管理。被安排手术的病人按照择期手术的要求进行术前检查，依照规定包括一个详细的病史和体格检查。实际上，繁杂的检查会带来潜在的严重和有害后果。为了解释异常的检查结果，就需要另外一系列的检查。一些侵入性检查有潜在的危险。一般异常结果如果被简单的忽视，会有潜在的医学法理责任。繁杂的检查往往会发现不正常的结果，导致不能进行任何手术选择，麻醉药物选择和麻醉操作。一些中心用手提电脑采集病史。依赖病人回答得到的各种问题分类列表可以得到广泛的信息。交互式访问的结果，电脑会提供一份详细的有关病史和推荐术前要做检查的详细报告。一些机构对健康男性和40-50岁以下女性的表浅手术部要求进行任何检查。
10.Should an internist evaluate each patient before ambulatory surgery?
The same rules and standards regarding a complete preoperative evaluation of patients apply to surgery scheduled on either an inpatient or an ambulatory basis. Accordingly, an internist or medical subspecialist should be consulted regarding the advisability of surgery at a particular moment in time whenever the stability of a patient’s medical condition is questionable. Although it may be true that the resultant physiologic perturbations associated with some ambulatory surgery procedures may be characterized as minor, there is nothing minor about the administration of an anesthetic. A complete written history and physical examination are required as part of the medical record before the administration of anesthesia and commencement of surgery. For patients with no or stable co-existing medical conditions, the complete history and physical can be done by the surgeon. However, for patients with significant co-existing medical diseases and/or whose medical status may be questionable, there should be an evaluation completed by the internist or medical subspecialist.
10.每个门诊手术病人都要进行内科医师评估吗？
不论是住院或门诊准备手术病人都执行术前相同的规则和标准进行评估。一般无论任何时候病人的医疗状况有问题时，都要进行内科和专科医生会诊。有小手术，但是没有小麻醉。对于没有或有稳定疾病状态的，由外科医生写出完整的病史和体格检查。对明显伴有其他疾病和医疗状况不稳定时，需要由内科医生和专科医生作出完整的评估。
11.Is anxiolytic premedication advisable before ambulatory surgery, and what agents are appropriate?
Because the goal of anesthesia for ambulatory surgery is to permit early discharge to home, there was concern that the administration of short-acting anxiolytic or analgesic premedication might delay recovery from anesthesia and thereby prolong time in the postanesthesia care unit (PACU) with a resultant delay in patient discharge. However, no significant differences in recovery times can be demonstrated after short-acting premedicants have been administered. The effects of more potent and longer-acting anesthetics and the surgical procedure itself contribute in a more significant fashion to the recovery time before a patient may be discharged. However, although time to discharge, a gross measurement, may remain unaffected, tasks that require fine coordination and speedy reaction times may still be deleteriously affected.
Many patients experience anxiety in the immediate preoperative period, and pharmacologic management is quite acceptable. The administration of either diazepam, 5–10 mg orally, 1–2 hours before surgery or midazolam, 1–2 mg intravenously, after an intravenous catheter is placed before surgery can ameliorate distress if deemed desirable. The amnestic effect of intravenous midazolam is powerful, and patients may not remember having seen their surgeon. Midazolam can also be given orally, although much larger doses are required because of first-pass hepatic degradation (0.5–1 mg/kg orally). Opioid premedication may contribute to the incidence of postoperative nausea and vomiting.
Preoperative oral doses of clonidine, a centrally acting a2-adrenergic agonist have been used to provide sedation, reduce anesthetic requirements, and decrease episodes of hypertension and tachycardia during intubation and maintenance of anesthesia. Side-effects of this class of drugs may include dryness of the oral cavity, hypotension, as well as undesirable sedation extending into the postoperative period. Relaxation techniques have been taught preoperatively to patients and may aid in the reduction of anxiety level. Instruction of these techniques, however, is time-consuming and requires patient motivation, and is therefore usually reserved for selected patients with extreme phobias.
11.门诊手术前建议给抗焦虑药吗？哪些药物合适呢？
因为门诊手术麻醉的目标是早期让病人离院回家，所以关注所给的短效抗焦虑和镇痛药可能会延长麻醉恢复时间和在麻醉后恢复室（PACU）观察的时间，耽搁病人离院。而实际，没有资料证明术前给短效药物对恢复时间的影响有显著差异。长效强效麻醉药物和手术本身更能影响到病人达到离院的恢复时间。而实际，虽然对病人离院前的粗略评估可能没有影响，但是对指令性运动和快速反应时间还是有影响的。
大多病人在术前刻都存在焦虑状态，因此术前给药是被广泛接受的。如果需要术前1-2小时口服5-10mg地西泮或建立静脉通道后静脉1-2mg咪唑安定可以减轻不适。咪唑安定顺行性遗忘作用很有用，病人可以不能回忆已经见到的手术医生。咪唑安定可以口服，但是因为首过效应需要的量较大（05-1mg/kg）。预给阿片类药物可以减轻术后发生的恶心呕吐。
术前口服剂量的可乐定，一种证明有镇静作用的中枢α2受体激动剂，可以减少麻醉药量和预防插管和维持过程中高血压和心动过速的发生。这类药的副作用还有口腔干，低血压和不希望发生的术后长时间镇静。术前放松技术的指导有助于帮助病人减轻焦虑水平。实际上，这些技术的指导，需要消耗时间和需要病人的配合，因此通常只对那些有特别恐怖的病人进行。
12.What are the reasons for last-minute cancellation or postponement of surgery?
The incidence of last-minute postponement or cancellation of ambulatory procedures exceeds the cancellation rate for the inpatient population. A multiplicity of factors can be operative. Repeat physical examination by the surgeon may reveal the disappearance of pathology. Patients may forget and ingest either solid food or liquids before arrival at the medical facility. Abnormal results on tests that were not available or not previously reviewed may be discovered. Communication between the surgeon and anesthesiologist regarding laboratory abnormalities will help to reduce the incidence of last-minute cancellation of surgery, the consequences of which distress both patient and surgeon and make for inefficient use of available operating room time. Additional questioning may reveal either new symptoms or significant history that was not previously elicited. Physical findings apparent on a last-minute assessment by the anesthesiologist may preclude the safe administration of an anesthetic. Examples include an acute upper respiratory tract infection or an exacerbation of bronchospastic pulmonary disease. Finally, patients may arrive late to the facility or without a responsible escort to accompany them home.
Because the escort’s function in the postoperative period goes beyond merely ensuring a safe means of transportation home, in the absence of a designated appropriate escort, surgery should not proceed unless alternative care arrangements are made. If the patient speaks only a foreign language, the escort may serve as an interpreter throughout the perioperative period. After surgery, the escort will receive the postoperative instructions and serve as a companion to the patient during the first 24 hours following the completion of surgery. Assistance in the performance of activities of daily living will be rendered as required. Additionally, the escort will be available to summon medical assistance in the event of a medical, surgical, or anesthetic complication.
12.最后一刻取消或推迟手术的原因？
门诊病人最后一刻取消或推迟手术的机率高于住院病人。有很多原因，如外科医生再次检查发现病理学变化的消失，病人因为忘记在来到医院前有固体或流质饮食，用处不大的或之前没有发现的异常检查结果。外科医生和麻醉医生对异常检查结果的交流有助于减少最后一刻取消手术的发生，最后一刻取消手术会使外科医生及病人感觉到郁闷，并且不能充分利用手术时间。另外的问题还有新出现的症状或之前没有引出的病史，最后一刻麻醉医生作出的评估体检认为麻醉不安全，如急性上呼吸道感染或支气管肺部疾病的恶化。也可能因为迟到或没有可以负责任的护送人员陪伴而取消。
因为护送人员不仅仅是简单的在术后把病人安全的转运回家，在没有制定的护送人员时，手术不能进行，除非已经做好护理安排。如果病人只会讲外语，护送人员从术前期就可以充当翻译，术后护送人员将接受术后指导并且在术后的第一个24小时专职陪伴，护送人员还可以进行普通的医疗辅助如医疗，手术或麻醉并发症等。
13.What is the ideal anesthetic for ambulatory surgery?
No single anesthetic is ideal for every procedure performed. However, the goal of the anesthetic is to allow for patient discharge shortly after the procedure’s completion. An ideal general anesthetic agent would have a rapid onset, permit a rapid return to baseline levels of lucidity and equilibrium, and be free of deleterious cardiovascular and respiratory effects. It would provide intraoperative amnesia, analgesia, and muscle relaxation and would possess anti-nausea and anti-emetic properties. Unfortunately, such a marvelous single agent is not in existence at the present time. In an attempt to avoid some of the unpleasant side-effects associated with general anesthesia, regional anesthetic techniques including field blocks, intravenous regional block (Bier block), various approaches to the brachial plexus, ankle block, and spinal and epidural anesthesia have been offered to patients as an alternative to general anesthesia.
13.什么是门诊手术的理想麻醉？
没有一种麻醉药对所有手术都理想。这种麻醉的特点就是允许病人术后早期离开。一种理想的麻醉药将是快速起效，快速恢复到术前的清醒和平静水平，并且无有害的心血管和呼吸功能影响。它能提供术中的遗忘、镇痛、肌松，并且拥有显著的抗恶心呕吐特性。不幸的是，到现在仍然没有一种这么神奇的药物存在。为了避免全麻带来的不愉快的副作用，区域阻滞技术包括部位阻滞，静脉区域阻滞，各种入路的臂丛阻滞，踝部阻滞和硬膜外阻滞都用来替代全麻。
14.Are there relative or absolute contraindications to the administration of a general anesthetic in the ambulatory setting?
Sometimes the administration of a general anesthetic clearly should be avoided, if possible. Examples of such cases are a patient with severe, poorly controlled asthma or documented bullous emphysema. In these cases, lesser concern should be given to the possibility of a postdural puncture headache (PDPH) if more serious sequelae are likely to result during or after administration of a general anesthetic. This, however, is the exception rather than the rule, and in most instances the final choice of anesthesia should remain with the patient, guided, of course, by the anesthesiologist. Additionally, when a patient arrives for extremely minor surgery without an escort, a local anesthetic injection alone might suffice for anesthesia. This might allow the patient to return home unaccompanied. Unfortunately, it sometimes becomes necessary to supplement a local anesthetic with intravenous sedation, and under these circumstances an escort would then be mandatory.
14.有没有门诊手术给全麻药的相对或绝对禁忌证？
可能情况下，应尽量避免给予全麻药。例如有一个严重的控制较差的消除病人或一个有明确资料证明大泡型肺气肿病人，这种情况下主要不是考虑硬膜外穿刺后头疼（PDPH）的问题更需要考虑的全麻中或全麻后的管理问题。而这是个规则的例外，大部分情况下最终的选择权应该留给病人，当然要在麻醉医生的指导下。另外，当一个病人只需要做一个非常小的手术并且没有陪护人员时，局麻药注射就足够了。可以不要人陪护直接回到家里。不幸的是，有必要静脉给予镇静药来补充。这种情况下陪护人员是必须的。
15.What are the advantages and disadvantages to performing a conduction anesthetic in the ambulatory patient?
Employing regional anesthesia in the ambulatory surgery patient has a number of potential advantages. If little or no intraoperative sedation is required, little or none of the “hangover” effect will be present throughout the postoperative period. Patients who express fear about losing consciousness or the loss of control associated with a general anesthetic may prefer a regional technique. Some patients have a strong desire to remain awake to view arthroscopic surgery as it is being performed.
Spinal or epidural anesthesia, however, has potential disadvantages. There had been concern regarding the apparent increased incidence of PDPH in patients who ambulate postoperatively. However, experience has shown that the incidence of PDPH is equal among patients who are nonambulatory and ambulatory, but that the onset may be delayed in patients who remain recumbent for a longer period of time. If spinal anesthesia is chosen, the use of conventional smaller gauge needles as well as newer designs (Greene, Sprotte, Whitacre) that include modifications at the tip to be less traumatic appear to markedly reduce the incidence of PDPH. The theory behind the pencil-point Greene, the conical Sprotte, or side port Whitacre needles is that splitting rather than cutting of the dural fibers occurs, which may reduce the amount of cerebrospinal fluid (CSF) leak.
Reduction of the incidence of PDPH to approximately 1–2% or less would be an ideal goal. Technical failure rates of the various needles must also be figured into the overall equation.
Patients must always be informed regarding the potential for development of a PDPH because ambulatory patients usually expect to resume their normal activities shortly after surgery. Additional recommendations to reduce the incidence of headache include keeping the bevel edge of the conventional needle parallel to the longitudinal axis of the body and the dural fibers and avoiding multiple attempts at subarachnoid needle placement. Maintenance of adequate hydration intraoperatively and postoperatively and avoiding straining and lifting postoperatively are recommended.
Patients presenting with a persistent PDPH may require an epidural blood patch for relief. Therefore, it is especially important to follow up patients with a telephone call at 24–48 hours after surgery to inquire about the presence of any problems. Conservative treatment of a PDPH in the ambulatory patient includes traditional analgesics, fluids, and bed rest. Performance of an epidural blood patch should be considered early if the headache is perceived by the patient to be extraordinarily severe or incapacitating, or if the patient must return to work immediately, or care for children.
In an attempt to avoid the possibility of a PDPH in younger patients, an epidural anesthetic may be offered to patients if a regional technique is requested or medically indicated. Though an epidural requires greater technical expertise and may be slightly more time-consuming to perform when compared with a spinal, the insertion of a catheter allows additional incremental doses of anesthetic to be added if surgical time is unexpectedly lengthened. Additionally, the use of shorter-acting local anesthetics allows for timing the block to wear off shortly after the procedure is completed. However, the incidence of headache after unintended dural puncture with larger gauge epidural needles is significantly higher. It is interesting that the reported incidence of headache following a general anesthetic in ambulatory patients exceeds the incidence of headache after regional anesthesia, although it is usually much less incapacitating and is self-limiting. It is postulated that the cause of the headache is intraoperative and postoperative starvation and an element of dehydration.
Spinal anesthesia provided by tetracaine and bupivacaine has been associated with recovery room stays as long as 6–8 hours. This must be considered before performing a regional anesthetic, especially if the procedure is to be done later in the day. Another potential disadvantage of administering a spinal anesthetic in an ambulatory patient is the potential for persistence of autonomic blockade for 1–2 hours following restoration of motor function. This can result in the inability to urinate and the need for bladder catheterization. It appears that increasing duration of sympathetic blockade correlates with an increased incidence of urinary retention.
28.How is pain best controlled in the ambulatory patient in the PACU?
Management of postoperative pain in the PACU as well as after discharge is of major concern to the anesthesiologist. Adequate pain relief must be achieved before a patient may be discharged and patient comfort in the postoperative period is important. The prevention of postoperative pain appears much easier to accomplish than the treatment of pain that has been allowed to reach significant intensity. Unfortunately, the occasional inability to manage postoperative pain remains a cause of unexpected overnight hospitalization.
In procedures for which patients can be anticipated to experience significant postoperative discomfort, the addition of an opioid as part of the anesthetic is helpful. A propofol anesthetic will not provide postoperative analgesia. The intraoperative administration of long-acting local anesthetics such as bupivacaine, 0.25–0.5%, at the surgical site may provide hours of postoperative pain relief. This technique has proven to be most efficacious following inguinal and umbilical hernia repairs and minor breast surgery. The efficacy of intra-articular local anesthetics and opioids following arthroscopy of the knee joint has been shown to be of value. Other techniques such as performance of a penile block or the topical application of lidocaine jelly on the penis following circumcision have proven effective in reducing discomfort. The use of ilioinguinal and iliohypogastric nerve blocks is efficacious in adults and children following herniorrhaphy. Repeating maxillary or mandibular nerve blocks at the conclusion of oral surgery is efficacious.
In the PACU, careful titration of small intravenous doses of opioids can safely provide satisfactory analgesia. The blood levels of opioids that are required to provide analgesia are less than those that usually result in significant respiratory depression or marked oversedation. Fentanyl is the narcotic of choice in the postoperative period for treating pain. Its duration of action is modest, and intravenous doses of 25–50 mg may be repeated every 5 minutes until satisfactory pain relief has been achieved. Medicating patients with oral opioid preparations before discharge will provide a patient with a more comfortable trip home because the intravenous drugs administered in the PACU have relatively short durations of action.
The home use of patient-controlled analgesia systems permits the discharge of patients who are expected to experience pain that may not be sufficiently controlled with oral agents. Experiments with patient-controlled analgesia in the home have found this modality of pain relief to be both safe and effective. Oxycodone and codeine are suitable for amelioration of mild-to-moderate pain but are not strong enough to prevent hospitalization in a patient who experiences severe pain.
Ketorolac, a nonsteroidal anti-inflammatory agent, has been administered orally, intramuscularly, and intravenously in an attempt to prevent and relieve pain and reduce opioid requirements. The drug itself is free of opioid-related side-effects including sedation and vomiting. Some are hesitant to employ this class of drugs because of their potential for causing bleeding. Further, when administered orally, gastric irritation may be encountered. COX-2 inhibitors minimize the potential for postoperative bleeding and the risk of gastrointestinal complications and thus are becoming popular as a non-opioid adjuvant for treating postoperative pain.
28. 怎么使门诊手术病人在麻醉后恢复室（PACU）得到最好的镇痛？
PACU病人术后疼痛管理是继出院之后对麻醉医生最重要的事情。离院前必须充分减轻疼痛和病人术后期的舒适是重要的。预防术后疼痛发生较治疗疼痛达到一定的程度要容易的多。不幸的是，偶尔发生难以处理的疼痛，会导致我们不期望发生的病人不得不住院过夜留置观察。对于预测可能发生术后不适病人麻醉时，加入阿片类作为麻醉的一部分是有用的。异丙酚麻醉不能提供术后镇痛。术中手术部位给予0.25-0.5%的长效局麻药可以产生术后几个小时的疼痛减轻。在腹股沟疝和脐疝修补术，小范围乳腺手术效果都非常明显。关节镜检查后，膝关节腔内给局麻药和阿片类药物也是很有效的。其他如对包皮环切病人阴茎神经阻滞，或表面涂抹利多卡因膏剂都有助于减轻不适。髂腹股沟和髂腹下神经阻滞在成人和小儿疝修补病人都是有效的。多次上下颌神经阻滞对口腔手术病人也是有效的。
在PACU病人精确静脉给阿片类药物可以安全的达到满意的镇痛。产生镇痛的血药水平要低于引起显著呼吸抑制或过度镇静的水平。芬太尼是疼痛治疗可以选择的麻醉药。它作用时间中等，静脉25-50mg，每分钟可重复给药直道达到我们期望的减轻程度。给准备离院的病人口服阿片类镇痛药，可以使病人回家途中更舒适，因为在PACU静脉给药作用时间较短。
对认为口服镇痛药不足以有效镇痛的病人来说，家庭用自控镇痛（PCA）装置的使用也可以让病人离开医院。对病人家庭自控镇痛的研究表明它是安全、有效的。羟考酮和可待因适合改善轻中度疼痛，但对因疼痛住院的病人是不够的。
痛力克是一种非甾体类抗炎药，曾被口服，肌注和静脉给药试图预防和减轻疼痛，减少对阿片类药物的需求。它本身没有阿片类相关的恶心、呕吐等副作用。但是医生对使用这类药物很犹豫，因为它有潜在出血的危险。另外，口服时对胃有刺激。COX-2抑制剂可潜在的减少出血，和胃肠并发症的风险，因此常作为非阿片类药物治疗术后疼痛。
29.What discharge criteria must be met before a patient may leave the ambulatory surgery center?
Most institutions divide postanesthesia care into two phases. The first phase begins when the patient first enters the recovery area. The second phase, or step-down phase, begins after stability of vital signs has been achieved and the major effects of anesthesia have dissipated. At this point, the patient can be comfortably transferred into a recliner chair, either in the same area or in another unit (Table 77.5).
Patients who have received a spinal or epidural anesthetic can only be discharged when full motor, sensory, and sympathetic function has returned. An inpatient who will remain at bed rest might be discharged from the PACU to the nursing unit while minimal residual neural blockade persists; in the case of the ambulatory patient, however, it is essential that the block has completely dissipated.
Following administration of an epidural or spinal anesthetic, the patient should demonstrate the ability to void. This provides evidence that residual sympathetic blockade has dissipated. Of course, before attempting to ambulate a patient, it is essential to ensure that all motor block has resolved.
Patients who have received an ankle block, brachial plexus block, or peripheral nerve block may be discharged despite the persistence of residual anesthesia or paresthesias. The arm or foot should be protected from harm with either a sling in the case of the arm or a bulky dressing in the case of the foot. The patient needs to be reminded that in time the block will dissipate and discomfort will appear. For this reason, instructions should be given to take the prescribed oral analgesic medication at the first sign of discomfort, because pain is most readily treated before it becomes excruciating.
Patients who have received general anesthesia may awaken either in the operating room or shortly after transfer to the PACU. Although the patient may appear to be lucid and oriented, numerous criteria must be satisfied before a patient may be considered to be ready for discharge from the facility. A restoration of vital signs within 15–20% of the preoperative baseline is ordinarily required. Patients should demonstrate an intact gag reflex and the ability to cough effectively and swallow liquids without difficulty. It is not necessary for patients to eat before discharge. Forcing patients to ingest unwanted food in the absence of hunger may simply serve to increase the incidence of postoperative nausea and vomiting. Ordinarily, the patient is asked to demonstrate the ability to tolerate a small amount of liquid. If a patient experiences mild nausea and has not been able to ingest more than a few sips without precipitating vomiting or increased nausea, it is foolish to persist. Discharge can still be considered, but written instructions must be provided regarding steps to be taken (contact facility or surgeon) if there is continued inability to tolerate fluids. It is important to ensure that a normal state of hydration has been achieved before discharge. This is especially important following surgery in the oral cavity, where postoperative pain may preclude early oral intake.
Unless the patient was previously unable to walk or the procedure performed precludes ambulation, patients should be able to walk with assistance and without experiencing dizziness. If crutches are required, it should not be assumed that the patient received preoperative instruction. Additional instruction should be offered. Hemostasis should be present at the surgical site, and control of pain should be satisfactory. The preoperative level of orientation should be achieved, although a mild degree of residual sedation is acceptable.
It is not essential for a patient to demonstrate the ability to urinate unless genitourinary, gynecologic, or other surgery has been performed in the inguinal or perineal region. The patient and the escort should be instructed of the need to contact either the ambulatory facility or the surgeon if the patient has not voided within 6 hours following discharge from the recovery area.
Postanesthesia discharge scoring systems have been proposed and developed for the purpose of assessing when home readiness is achieved in the postoperative period. Criteria such as mental status, pain intensity, ability to ambulate, and stability of vital signs are given numeric values. A total score above a particular number may indicate a high likelihood of readiness for discharge. To be practical, a scoring system must be readily understood, simple to employ, and objective. Sophisticated pen-and-paper and neuropsychological tests to assess recovery from anesthesia are reserved solely for research purposes. Actually, after stability in vital signs is achieved, the ability of a patient to walk and urinate may be the best measure of a patient’s gross recovery from an anesthetic and signal readiness for discharge. These activities indicate return of motor strength, central nervous system functioning, and restoration of sympathetic tone.
Each patient and escort should receive a set of detailed, written discharge instructions regarding activity, medications, care of dressings, and bathing restrictions. Instructions must be reviewed verbally with the patient and escort, and they must be signed by the patient or escort, if the patient is incapable. Both must be aware of the need to contact the facility in the event of untoward reactions or any difficulties that may arise such as bleeding, headache, severe pain, or unrelenting nausea or vomiting. The majority of postoperative complications occur after the patient has been discharged. Therefore, it is important to ensure comprehension of all information by the patient or designated escort (Table 77.6).
Most states have a mandatory requirement that patients who have received other than a local anesthetic be discharged in the company of a responsible adult. Current definitions of “responsible adult” vary and may be broadened to include emancipated minors or responsible older children. Theoretically, the companion should be willing and able to remain with the patient for at least the first 24 hours after surgery. This is especially important when dealing with the geriatric or debilitated patient. Problems may arise when an octogenarian patient is discharged in the company of an octogenarian spouse. Ideally, two adults should accompany pediatric patients from recovery room to home. After discharge, a child may suddenly experience nausea or vomiting, pain, fright, or disorientation. A parent who is driving a car cannot possibly attend to both responsibilities simultaneously.
A clear distinction is made between “home readiness” and “street fitness.” Home readiness signals that the time has arrived to discharge the patient from the recovery area. On the other hand, “street fitness” is attained after approximately 24 hours have elapsed, when most of the more subtle and persistent central nervous system effects of general anesthesia have dissipated. Patients must be advised not to resume normal activities immediately upon returning home.
Formal discharge criteria must be in place, and final evaluations should be conducted immediately before a patient’s discharge from the unit. All perturbations from normal, including vital signs and unusual symptoms, must be addressed.
Every attempt must be made to avoid premature discharge of the patient from the PACU. The consequences of such faulty judgments may include the necessity for emergency care elsewhere and possible readmission to another health care facility. When any element of doubt exists as to the stability or suitability of a patient for discharge, the better part of valor is to arrange for hospital admission for overnight observation.
29. 病人离开门诊手术中心必需达到的标准是什么？
大部分机构把麻醉后监护分为两期。一期从病人进入复苏区开始。二期从病人生命体征已经稳定，主要麻醉效应已经消失开始。这时，病人可以舒适的坐进躺椅，仍在这个房间或到另一个房间（表 77.5）。
椎管内麻醉的病人只有运动，感觉和交感神经功能功能完全恢复才能离开。在PACU卧床休息的住院病人，当仅剩骶部神经阻滞时可以回到护理病房。门诊手术病人最主要的是阻滞作用完全消失。
椎管内麻醉病人应证明有排泄能力，这是骶部交感神经消失的证据。当然，准备行走的病人，运动神经完全恢复是必须的。
接受踝部阻滞，臂丛和外周神经阻滞的病人，即使麻醉作用或感觉异常持续存在也可以离开。手臂和脚或使用吊带或用较厚的包扎，要进行保护以免受伤。病人需要提醒当阻滞作用消失时会有不适。因此要给予病人指导和开出口服镇痛药在开始出现不适时使用，因为疼痛在变严重之前最好治疗。
全麻病人可以在手术室或转运到PACU不久清醒。尽管病人看起来是清醒，有正确定向力的，但让病人离开之前还有很多标准要到达满意。生命体征在术前基线范围的15-20%是基本要求的。病人要有完整的gag 反射，有效地咳嗽，无困难进食液体。没有必要让病人在离开之前进食。强迫病人感到饥饿时进食不想吃的食物只会增加术后恶心呕吐的发生。如果病人只有轻度恶心，还没有达到进食几小口不引起呕吐和恶心增加的程度，坚持让病人进食是愚蠢的做法。如果一直不能进食液体，也可以考虑让病人离开，但必须提供书面的分步骤指导（如何联系机构和外科医生）。确保离院前体液足够是重要的。尤其是口腔手术病人，因为术后疼痛导致不能早期经口进食。
除非病人术前就不能行走或手术原因，病人应该在其他设备辅助下能够行走，并且不头晕。如果需要拐杖，不要认为病人术前已接受过指导，应该给予另外的指导。手术伤口应该已经止血，疼痛控制的满意。应该回到术前的定向力水平，即使有一点轻度的镇静残余也是可以接受的。
除非是在腹股沟或会阴区进行的泌尿生殖手术，妇科或其他相关的手术，没有必要让病人证明有排尿能力。病人和护送人员要被告知，如果离开恢复区后6h仍未排泄，要通知医院或外科医生。
已经开发了麻醉后允许离开评分系统，目的是评估术后何时达到准备离开的标准。如精神状态，疼痛程度，行走能力，数字评分的生命体征的稳定性等，总评分高于某个特定值说明进行离院准备的可能性高。从实用方面讲，评分系统因该易于理解，应用简单，并且客观。精确的书面神经生理学测试已经单独用来进行麻醉恢复程度的研究评估。事实上，生命体征恢复，能够独立行走和排尿或许是对麻醉后恢复程度及可以作离院准备粗略评估的最好指标。这些活动是运动强度，中枢神经系统，交感系统恢复的表现。
每个病人和护送人员应该给予一套详细的包括活动、用药、穿衣，限制沐浴的详细指导。病人和护送人员必须口述这些指导，并签字，病人不能时，护送人员代签。两个人都必须意识到当不良反应或任何其他困难如出血，头疼，严重疼痛，严重恶心，呕吐发生时，有联系医院的需要。术后并发症大多在病人离开后发生。因此，有必要确保病人或代为签字的护送能够人员充分理解上面所有的信息（表77.6）。
大部分机构强制规定，对接受过大于一种局麻药的病人要有负责人的成人陪伴才能离开。所谓“负责人成年人”定义现在已经放宽，包括空闲的未成年人或较大的儿童。理论上讲，陪伴人员应该健康并且能在术后第一个24小时和病人呆在一起。这对老年和虚弱病人尤其重要。如果一个八旬老人被他八旬的配偶陪伴下 被允许离开，就有出事的可能。儿童出院后可能突然出现恶心呕吐，疼痛，恐惧或定向力障碍，一个正在驾车的父母可能不能同时处理好孩子。
“适合在家”与“可以上街”有明显的区别。适于在家是达到可以从恢复区离开的标准。而“可以上街”是在24h后，当大部分细微的和持续存在的全麻对中枢神经系统的影响已纪完全消失后。必须建议病人在回家后不立即进行正常活动。
病人离开前必须达到标准，并在离开前刻作最后的评估。必须排除对对正常所有状态如生命体征和异常症状的所有干扰。
必须尽最大努力避免让病人过早离开PACU。错误判断的结果就是在它处的急救和在其他医疗机构的再入院。当对病人情况的稳定性或是否离开有疑问时，最好的办法就是过夜留置观察。
30.What are the causes of unexpected hospitalization following ambulatory surgery?
Although a patient may be scheduled to return home after surgery, admission may be required for a host of reasons. Approximately one quarter of the unexpected admissions following surgery are anesthesia-related. The remainder result from either medical or surgical complicating factors (Table 77.7)
Most ambulatory surgical facilities experience an unexpected hospital admission rate that ranges from less than 1% to approximately 4%. Unexpected hospitalization is greater with general anesthesia compared with local or regional anesthesia. As might be anticipated, the addition of intravenous sedation to a local anesthetic increases the complication rate. Nausea and vomiting, dizziness, bronchospasm, and delayed emergence from anesthesia are common causes of anesthesia-related hospital admission.
30. 门诊手术后意外住院的病人怎么处理？
尽管病人术后被允许回家，但还会因为很多原因入院。其中，与术后麻醉相关的约有1/4。其他的是医疗和手术因素（表 77.7）。
大多门诊手术机构意外再入院率在低于1%到大约4%不等。全麻较局麻或部位麻醉发生率高。可以想象，局麻附加静脉镇静增加发生率。恶心、呕吐、眩晕、支气管痉挛、延迟苏醒是常见麻醉相关再入院的原因。
31.When may patients operate a motor vehicle after receiving a general anesthetic?
Current recommendations are to advise patients to refrain from operating heavy machinery including driving a car for approximately 24–48 hours after the administration of either a general anesthetic or intravenous sedation. While a patient may appear to himself or herself and to others to be completely recovered, subtle psychomotor disturbances and cognitive deficiencies may persist in the postoperative period. Important decision-making, as well as activities requiring fine motor coordination, should be postponed until after the first postoperative day. Despite admonitions to the contrary, postoperative patient surveys have revealed that some patients drive their automobiles within 24 hours after surgery, and some may even drive home from the facility.
As a result of central nervous system derangements or the surgery itself, patients may experience minor slips or even major falls after discharge. Some of these events may be related to confusion or subtle alterations in mental state. Others may be due to dizziness or pain. It is hoped that anesthetic agents of the future will be free of the prolonged and potentially hazardous central nervous system dysfunction seen with currently available drugs.
31. 全麻后的病人何时能进行机动车驾驶？
当前建议全麻或接受静脉镇静的病人，术后以后的24-48h不操作重型机械，包括开车。在自己或他人看来已经完全恢复的病人，轻微精神运动性障碍或定向力障碍是持续存在的，这些行为应该推迟到术后第二天。但与警告相反，术后调查发现有一些病人在术后24h驾驶车辆，甚至直接开车回家。
病人也可能因为中枢神经系统紊乱或手术本身会有脚步较轻的感觉，甚至跌到。其中的一些和意识混乱或精神状态的变化有关。还有其他原因如眩晕或疼痛。也希望未来的麻醉药不再有后续的，潜在中枢神经系统功能不全的危险。
32.What is the role of aftercare centers for the ambulatory surgery patient?
Following some surgical procedures, patients may experience significant postoperative pain that cannot be readily controlled with oral opioids. Additionally, although they may require some skilled nursing observation or specialized care, these may be accomplished outside the setting of an acute care hospital both at lower cost and with greater comfort for the patient and family. With this in mind, the concept of a recovery care facility was born, thus creating a new category of inpatient postsurgical care. This healthcare model integrates ambulatory surgery with overnight or extended care outside of a hospital. Examples of procedures included in the present trial include hysterectomy, cholecystectomy via laparotomy, shoulder repairs, and mastectomies. If this type of facility is unavailable, appropriate use of home care services including newer modalities of pain control may still allow a patient to avoid inpatient postoperative care.
32.门诊手术病人术后恢复中心的地位是什么？
一些手术后，病人会有口服阿片类药物不能控制的术后疼痛。所以他们需要一些技术性的护理观察或特殊护理，这可以在急救医院外获得，并对病人和家人来说更便宜，舒适。带着这种理念，恢复护理医疗机构的概念诞生了，出现了一种新的住院病人术后监护单位。这种模式整合了需要过夜观察的门诊手术病人或延伸的出院后服务。例如子宫切除术，腹腔镜胆囊切除术，shoulder repairs, 乳房切除术。如果这种形式也不能得到，可使用合适的家庭服务包括控制疼痛的新模式也能让病人免去术后的过夜住院观察。
33.Are quality assurance and continuous quality improvement possible for ambulatory surgery?
To ensure quality as well as patient satisfaction, follow-up telephone calls by an anesthesiologist should be made to all patients on the first postoperative day. Some facilities make two additional calls, one on the evening of surgery and another 1 week following surgery. Postage-paid postcards may be sent to patients requesting information on the overall experience as well as specific areas of care. Space may be allocated for the patient to note side-effects or adverse occurrences. Depending on surgeons to provide accurate feedback regarding complications is unreliable. Therefore, a mechanism for follow-up must be in place to uncover and identify patterns that may require remedial action.
33.门诊手术质量能持续提高吗？
为了确保病人满意的服务质量，麻醉医生应该在术后一天对所有病人电话追踪服务。有些机构还有两项另外的服务，一个是手术当天夜里和术后一周。术后访问卡应该邮寄给病人，询问整个经历。要有空白地方让病人填写副作用或不良反应。依靠外科医生提供精确并发症反馈信息是不可靠的。因此，追踪服务机制必须进行，以发现和确认需要补救措施。