2015 麻醉專科醫師甄審 <口試題目>

一. 身高 145 cm，體重 90 kg 的 60 歲女性，患有睡眠呼吸中止症候群(obstructive

sleep apnea)，欲施行開腹式子宮切除手術。麻醉時應考慮哪些事情? (含術

前、術中、術後)

二. 有關靜脈麻醉 target controlled infusion (TCI)系統試簡述:

1. 藥物動力學原理

2. Plasma Concentration (Cp) vs Effect site concentration (Ce)

3. 麻醉深度監測

4. Pharmacodynamic interaction and multiple TCI pump combination

5. 麻醉臨床相關應用

三. 全身麻醉與區域麻醉如何影響體溫調節(thermoregulation)的三個過程

(afferent input, central control, efferent responses)?

1. 試從血管收縮、體溫變化與 shivering 等自律調節機制來加以闡述之

2. 請進一步說明此種影響會在臨床上，造成何種干擾與危害?

3. 針對老人、婦女、嬰兒等特殊族群，你會採取何種預防與處置策略

四. 一位懷孕婦女，預定進行闌尾切除術，試描述懷孕期間有何可能的生理變化

與麻醉處置與考量

五. 你的房區將有一位有 9 x 6 x 6 cm 大小的 mediastinal mass 的病人, 請問你要

如何進行術前的評估以及麻醉的處理?

六. 神經手術(neurologic surgery)中，外科醫師抱怨病人腦腫，請問您將如何處

置 ? (IICP 之評估以及快速降低顱內壓力與腦容量的方法)

七. 一位 20 歲男性，中午餐後從高處落下，導致頸椎受損，左側下頷骨骨折，

左側肱骨、左側股骨以及多處肋骨骨折，無明顯腹內出血以及顱內出血證據；

下午兩點，病患意識混亂，生命徵象為:heart rate 122 bpm, sinus tachycardia,

RR 28 breaths/min, BP:86/44mmHg, BT:36.8℃，你（妳）是麻醉醫師接到急診

照會插管，請問:

1. 外傷病人氣管插管適應症為何?

2. 在急診之緊急氣道處置流程為何？

3. 該病患頸椎受損且禁食時間不足，須做何處置?

4. 進行氣管插管時之藥物選擇?

5. 若預期使用 direct laryngoscopy 方式無法成功進行氣管插管，有何替代

工具?

八. 一位 26 歲孕婦(GA 35 wks, G1P0)因抱怨頭痛、右上腹痛與宮縮痛前來婦產科

求診，病患的 vital sign 為 BP: 150/100mmHg, HR: 84/min, SpO2: 100% room air，

理學檢查發現病人臉部與雙下肢水腫，子宮頸開 2 公分，張口做 Mallampati

class III，Lab data 發現血小板為 90,000/mm3, 尿蛋白 5g/d, 肝功能在正常範

圍。請問：

1. 哪些 symptom/sign 可以佐證該產婦有子癲前症?嚴重度為何?如何分級?

2. 若該產婦因胎兒窘迫要進行剖腹產，該如何麻醉?考量為何?

九. 67 歲男性病因為肝腫瘤來院做肝葉切除手術,病人有高血壓,糖尿病,CAD 病

史,手術二小時後心跳突然從 100/min 下降到 50/min

1. 請問此時該如何處置?

2. 若血壓為 60/40mmHg 進一步處置為何?

3. 假如還來不及用藥，心率即持續下降至 10-20/min，外科醫師回報手術

視野血液顏色變黑，此時該如何處置?

4. 經過十分鐘心肺復甦，心率恢復到 140/min, 血壓 60/30 mmHg，此時

該如何處置?

十. 請說明上腹部手術後採用硬脊膜外腔術後止痛的藥物(opioid or local

anesthetics)可能造成的副作用及處理方式。

口試題目 1

1. 身高 145 cm，體重 90 kg 的 60歲女性，患

有睡眠呼吸中止症候群(obstructive sleep

apnea)，欲施行開腹式子宮切除手術。麻醉

時應考慮哪些事情? (含術前、術中、術後)

參考答案

[Preoperative evaluation]

1. General review:

a. History of prior surgical procedures, their anesthetic challenges (e.g.

airway, IV access), need for admision to an ICU, surgical outcomes, and the

weight of the patient at that time.

b. Laboratory evaluations: fasting blood glucose, lipid profile, serum

chemistries (renal & hepatic function), complete blood count, ferritin, vitamin

B12, thyrotropin, and 25-hydroxyvitamin D.

c. Contraindications for surgery: include unstable CAD, uncontrolled severe

OSA, uncontrolled psychiatric disorder, mental retardation (IQ < 60), inability

to understand the surgery, perceived inability to adhere to postoperative

restrictions, continued drug abuse, and malignant disease with a poor 5-year

survival prognosis.

2. OSA

a. 可能伴隨的風險: systemic and pulmonary hypertension, left ventricular

hypertrophy, cardiac arrhythmias, cognitive impairment, persistent daytime

somnolence, and other factors.

b. 嚴重度分類: (藉 polysomnography 檢查之 apnea/hypopnea index (AHI))

i. Mild disease: AHI of 5 to 15 events per hour

ii. Moderate disease: AHI of 15 to 30 events per hour

iii. Severe disease: AHI of greater than 30 events per hour

c. 目前接受的治療:

i. 若是 moderate or severe disease 應接受夜間 CPAP 使用(要請病人帶到

PACU)

ii. 接受藥物減重治療，可能有的副作用與交互作用

1. phentermine: side effects includes tachycardia and hypertensmion

2. orlistat: side effects includes interferes with the absorption of fat-soluble

vitamins (need vitamins A, D, E, and K supplement), significant GI side effects

(diarrhea, steatorrhea, flatulence, fecal incontinence, and oily rectal discharge)

3. silbutramine: 美國 FDA 已下架, increased risks of stroke and acute

coronary syndrome

iii. 接受草藥減重，因常含 ephedrine 可能造成 hypertension, stroke, seizue,

& death

3. Identify other possible diseases associated with obesity:

p.s. Patients with metabolic syndrome have an increased risk for

cardiovascular disease events and are at increased risk for all causes of

mortality. Metabolic syndrome increases the risk of type 2 diabetes, which

itself is an important risk factor for atherosclerotic disease and may be

considered a coronary heart disease equivalent.1

[Induction]

1. Risk of aspiration

2. Deficulties in regional anesthesia: patient size, smaller epidural space

(drug dose), respiratory compromise if high regional block

[Intraoperative care]

1. airway maintenance 可能發生 airway obstruction

a. 原因: Increased amounts of adipose tissue deposited into oral and

pharyngeal tissues including the uvula, tonsils, tonsillar pillars, tongue,

aryepiglottic folds, and lateral pharyngeal walls. An inverse relationship exists

between the degree of obesity and pharyngeal area. Deposition of fat in the

lateral walls decreases the size of the airway and changes the shape of the

oropharynx into an ellipse with a short transverse and long anteroposterior

axis

2. difficult intubation

a. 原因同上 and short, thick neck, large tongue

b. 處理方法：

i. ramped position- ing or elevating the upper body and head of morbidly

obese patients to align the ear with the sternum horizon- tally, improves

laryngoscopic view.

ii. Fiberoptic intubation in an awake and sedated patient

c. 預備: equipment for emergency airway management (e.g. SGA, fiberoptic

bronchoscope)

3. rapid oxygen desaturation

a. 原因:

i. decreased vital capacity, inspiratory capacity, expiratory reserve volume,

and functional residual capacity

ii. closing capacity in obese individuals is close to or may fall within tidal

breathing

iii. lung compliance and respiratory system compliance are low

iv. derecruit gas exchange units

b. 處理方法：

i. preoxygenation with 100% O2 before induction

ii. consider CPAP 10 cmH2O during preoxygenation

iii. PEEP 10 cm H2O

iv. 25 degree head-up during preoxygenation

v. increasing tidal volume incrementally from 13-22 ml/kg

vi. recruitment maneuver (55 cmH2O for 10 sec)

vii. neuromuscular blockade must be fully reversed before the trachea is

extubated (e.g. TOF, 5-sec head lift, awake and following commands)

4. Patient positioning: (包括合適大小的手術台)

a. Pressure points, cause tissue necrosis and infections

b. rhabdomyolysis, resulted in renal failure, and death

5. 藥物劑量: titrated to desired clinical effect

a. IV drugs

i. LBW: (IBW*120%) hydrophilic medications

ii. IBW: propofol, vecuronium, rocuronium, remifentanil

iii. TBW: midazolam, succinylcholine, cisatracurium, fentanyl, sufentanil

iv. Maintenance dose: propofol based on TWB, sufentanil on IBW

b. Volatile anesthetics: Desflurane

[Postoperation]

1. 可能遇到的問題

a. post extubation airway obstruction: 上述原因加上 opiate and sedative

drugs needed for post-operative pain management (which decrease

pharyngeal dilator tone and increase the likelihood of upper airway collapse).

2. Post operative pain management

a. 未證實 IV analgesia, PCA or thoracic epidural analgesia 何者較佳

b. injection of local anesthetic

c. adjunct analgesia with nonnarcotic medications, unless contraindicated,

decreases opioid requirements.

口試題目 2:

有關靜脈麻醉 target controlled

infusion (TCI)系統試簡述:

1. 藥物動力學原理

2. Plasma Concentration (Cp) vs Effect

site concentration (Ce)

3. 麻醉深度監測

4. Pharmacodynamic interaction and

multiple TCI pump combination

5. 麻醉臨床相關應用

參考答案

1. Pharmacokinetic model

2. Plasma Concentration (Cp) and Effect site concentration (Ce)

3. Monitor system : BIS…..

4. Pharmacodynamic interaction and multiple TCI combination

5. TIVA，Conscious sedation, Deep Sedation

6. Close loop drug delivery system

口試題目 3

1. 全身麻醉與區域麻醉如何影響體

溫調節(termoregulation)的三個

過程(afferent input, central

control, efferent responses)?

可從血管收縮、體溫變化與

shivering等自律調節機制來加

以闡述之。

2. 請進一步說明此種影響會在臨床

上，造成何種干擾與危害?

3. 針對老、弱、婦、孺等特殊族群，

你會採取何種預防與處置策略?

參考答案:

1.1.1 Afferent input:

-Cold signals travel primarily via Aδ nerve fibers

-Warm information by unmyelinated C fibers

-Spinothalamic tracts in the anterior spinal cord

-Hypothalamus

1.1.2 Central control:

-Hypothalamus: mainly, for integration

-Spinal cord and other parts of the central nervous system: some

-Temperature threshold determination: unknown, may be mediated

by norepinephrine, dopamine, 5-hydroxytryptamine,

acetylcholine, prostaglandin E1, and neuropeptides.

1.1.3 Efferent responses:

-Vasoconstriction

-Shivering

-Behavioral regulation/compensations: dressing appropriately,

modifying environmental temperature, assuming positions that

appose skin surfaces, and moving voluntarily.

-Cutaneous vasoconstriction is the most consistently used

autonomic effector mechanism.

-Arteriovenous shunt components

-Nonshivering thermogenesis

-Sustained shivering: augments metabolic heat production by

50% to 100% in adults.

-Sweating is mediated by postganglionic, cholinergic nerves.

1.2 GA 下的影響:

-muscle relaxants: may inhibit shivering

-Anticholinergic drugs: inhibit sweating

-All general anesthetics may impair autonomic

thermoregulatory control.

-Warm-response thresholds are elevated slightly

-Cold-response thresholds are markedly reduced.

-Propofol, alfentanil, and dexmedetomidine: increase sweating

threshold and decrease asoconstriction and shivering thresholds.

-Isoflurane and desflurane: increase the sweating threshold; yet

decrease the cold-response thresholds

-Volatile anesthetics: inhibit vasoconstriction and shivering

-Clonidine: synchronously decreases cold-response thresholds,

while slightly increasing the sweating threshold.

-Nitrous oxide: decreases vasoconstriction and shivering

thresholds

-Midazolam: slightly impairs thermoregulatory control

-Sweating: is the best preserved major thermoregulatory defense .

1.3 Neuraxial Anestheia 下的影響:

-Sweating: mediated by postganglionic, cholinergic nerves

-Active vasodilation: inhibited by nerve block.

-Autonomic thermoregulation: impaired

-Intraoperative core hypothermia

-Shivering.

-Vasoconstriction thresholds: decreased

-Cold information iput: decreased

-Core temperature: decreases 0.5°C to 1.0°C

2. Hypothermia 的危害:

-Triples the incidence of morbid cardiac outcomes,

-Triples the incidence of surgical wound infections,

-Increases surgical blood loss and the need for allogeneic

transfusions by approximately 20%

-Prolongs postanesthesia recovery and hospitalization.

-Coagulation is impaired by mild hypothermia.

-Drug metabolism is markedly decreased (ex. the duration of

action of vecuronium is increased, MAC decreased) or increased

(ex. Propofol)

-Thermal comfort is markedly impaired by hypothermia.

-Increase oxygen consumption roughly 100%

-Increase intraoperative heat loss

-Uninhibited spinal reflexes, pain, decreased sympathetic activity,

pyrogen release, adrenal suppression, respiratory alkalosis, and,

most commonly, simple thermoregulatory shivering in response to

intraoperative hypothermia.

3.1 Elderly: the vasoconstriction threshold is approximately 1°C less in

patients 60 to 80 years old than in those between 30 and 50 years old

3.2 Female/pregnancy: Both sweating and vasoconstriction thresholds

are 0.3°C to 0.5°C higher in women than in men, even during the

follicular phase of the monthly cycle (first 10 days). Differences are

even greater during the luteal phase. Although central

thermoregulatory control is apparently intact even in premature

infants, thermoregulatory control may be impaired in older adults.

3.3 Infant:

-Nonshivering thermogenesis: increased

-Whole-body oxygen consumption: increased

-Heat production: doubled

-Shivering: does not occur in newborn infants and probably is not

fully effective until children are several years old.

-Thermoregulatory vasoconstriction: impaired

-Nonshivering thermogenesis: the most important

thermoregulatory response in infants

3.1.5 Prevention and management:

-Shivering during neuraxial anesthesia is markedly diminished by

maintaining strict normothermia.

-Shivering during neuraxial anesthesia can sometimes be treated

by warming sentient skin.

-Shivering can be teated by meperidine (25 mg intravenously [IV]

or epidurally), clonidine (75 μg IV), dexmedetomine, ketanserin (10

mg IV), and magnesium sulfate (30 mg/kg IV).

-Hypothermia can be managed by airway heating and

dehumidification, heated IV fluids and cutaneous warming

口試題目 4

一位懷孕婦女，預定進行闌尾切除術，

試描述懷孕期間有何可能的生理變化

與麻醉處置與考量

參考答案

Goal: Safety of 2 patients: mother and fetus

I. Maternal safety

懷孕生理變化(40%) 臨床麻醉注意事項

(20%)

Respiratory (10%)↑minute ventilation, O2

consumption;

↓FRC, residual volume

Edema of larynx and trachea

(5%)

Preoxygenation

Diffucult intubation

Smaller ET

CV (10%)↑CO, ↓SVR

Aortocaval compression

(5%) Supine

hypotension

syndrome

GI (10%)↓gastroesophageal

sphincter tone

↑gastric pressure

(5%) Aspiration

pneumonia

CNS (10%)↑sensitivity to regional

and general anesthesia

(5%) ↓MAC

II. Fetal safety

避免uteroplacental perfusion ↓、maternal hypoxia and

hyperventilation

1. 維持uteroplacental perfusion (20%)

避免hypotension: uterine displacement, fluid bolus,

trendelenberg position, vasopressor, leg elevation

避免術中uterine contraction

2. Teratogenicity

口試題目 5

你的房區將有一位有 9 x 6 x 6 cm

大小的mediastinal mass的病人, 請

問你要如何進行術前的評估以及麻醉

的處理?

參考答案

造成 mediastinal masses的原因有: thymoma, teratoma,

lymphoma, bronchogenic cyst....

Pre-operative evaluation

- 病患的 symptom/sign, 例如....平躺會不會喘...

- Dx: CT scan: the most important diagnostic tool

Heart echo: 若病患有 vascular compression

symptoms

3. Anesthetic management

1) Airway compression.....

保持 spontaneous breathing, awake intubation, local

anesthetis, inhalation with sevo (slow induction) or

propofol...

2) 壓到 great vessel......SVC syndrome...

下肢 IV line置放,會有的 S/S....

CPB standby?

若有回答出大人和小孩的不同, 可以加分!

- 若小孩在上發現 tracheobronchial compression 程度>50%,

即無法安全地完成 general anesthesia

- 小孩更危險, 因為無法確切描述 S/S, 其 airway 為 more

compressible cartilaginous structure

口試題目 6

神經手術(neurologic surgery)中，

外科醫師抱怨病人腦腫，請問您將如

何處置 ? (IICP之評估以及快速降低

顱內壓力與腦容量的方法) 1. 參考答案:

口試題目 7

1.一位 20歲男性，中午餐後從高處落下，

導致頸椎受損，左側下頷骨骨折，左側肱

骨、左側股骨以及多處肋骨骨折，無明顯

腹內出血以及顱內出血證據；下午兩點，

病患意識混亂，生命徵象為:heart rate

122 bpm, sinus tachycardia, RR 28

breaths/min, BP:86/44mmHg, BT:36.8

℃，你（妳）是麻醉醫師接到急診照會插

管，請問:

1)外傷病人氣管插管適應症為何?

2)在急診之緊急氣道處置流程為何？

3)該病患頸椎受損且禁食時間不足，須做

何處置?

4)進行氣管插管時之藥物選擇?

5)若預期使用 direct laryngoscopy 方

式無法成功進行氣管插管，有何替代工

具?

參考答案

1) 氣管插管適應症

•Cardiac or respiratory arrest

• Respiratory insufficiency

• Airway protection

• Need for deep sedation or analgesia, up to and including general anesthesia

• Transient hyperventilation of patients with space-occupying intracranial lesions and evidence of

increased intracranial pressure (ICP)

• Delivery of a 100% fraction of inspired oxygen (FiO2) to patients with carbon monoxide poisoning

2. • Facilitation of the diagnostic workup in uncooperative or intoxicated patients

2) 緊急氣道處置流程

3)頸椎受損且禁食時間不足

PROTECTION OF THE CERVICAL SPINE

Stabilization of the cervical spine will generally occur in the prehospital environment, with the patient

already having a rigid cervical collar in place.

In-line manual stabilization (not traction) throughout any attempt at intubation

Emergency awake fiberoptic intubation

PROPHYLAXIS AGAINST PULMONARY ASPIRATION OF GASTRIC CONTENTS

Application of cricoid pressure during attempts at positive-pressure ventilation should be considered

to reduce gastric inflation,

4)進行氣管插管時之藥物選擇與優劣?

Etomidate; Ketamine; Midazolam

Succinylcholine; Rocuronium

5)若預期使用 direct laryngoscopy 方式無法成功進行氣管插管，有何替代工具?

Gum elastic bougie Intubating stylet Indirect video laryngoscopy systems such as the GlideScope The laryngeal mask airway (LMA) Fiberoptic intubation Cricothyroidotomy.

口試題目 8

一位 26 歲孕婦(GA 35 wks, G1P0)因抱

怨頭痛、右上腹痛與宮縮痛前來婦產科

求 診，病 患的 vital sign 為 BP:

150/100mmHg, HR: 84/min, SpO2: 100%

room air，理學檢查發現病人臉部與雙

下肢水腫，子宮頸開 2 公分，張口做

Mallampati class III，Lab data 發現

血小板為 90,000/mm3, 尿蛋白 5g/d,

肝功能在正常範圍。

請問：

1. 哪些 symptom/sign 可以佐證該產婦

有子癲前症?嚴重度為何?如何分級?

2. 若該產婦因胎兒窘迫要進行剖腹產，

該如何麻醉?考量為何?

1. 參考答案

1. Severe preeclampsia(頭痛、右上腹痛、血小板為 90,000/mm3, 尿蛋

白 5g/d)

2. Gestational hypertension is defined as the onset of

hypertension (systolic blood pressure [SBP] > 140 mm Hg or diastolic

blood pressure [DBP] > 90 mm Hg) after 20 weeks gestation in a

previously normotensive parturient without proteinuria.

Preeclampsia is defined as hypertension (SBP > 140 mm Hg or DBP >

90 mm Hg) after 20 weeks gestation associated with proteinuria.

Preeclampsia is diagnosed when urine protein is greater than 300

mg/day or, alternatively, there is a protein/creatinine ratio of at

least 0.3. In 2013, massive proteinuria (> 5g in 24 hours) and fetal

growth restriction were eliminated as considerations of severe

preeclampsia. In addition, the term mild preeclampsia is no longer

used. Now only preeclampsia or preeclampsia with severe features are

defined. Severe features of preeclampsia include an SBP of 160 mm

Hg or greater or DBP of 110 mm Hg or greater on two separate occasions

at least 4 hours apart while on bed rest; thrombocytopenia; impaired

liver function with twice normal concentrations of liver enzymes;

right upper quadrant pain; progressive renal insufficiency with

serum creatinine greater than 1.1 mg/dL or a doubling of serum

creatinine without other known renal disease; pulmonary edema; and

new onset cerebral or visual abnormalities. In the absence of

proteinuria, preeclampsia can be diagnosed with new onset

hypertension as previously defined and presence of a severe feature.

Hemolysis, increased liver enzymes, and low platelet count syndrome

(HELLP) is defined as preeclampsia associated with hemolysis,

elevated liver enzymes, and low platelet count. Eclampsia is

preeclampsia complicated by seizure activity.

2. 如不急，可考慮 spinal anesthesia

如急產，需 general anesthesia

Difficult airway in obstetric patients Figure 77-4 page 2346-7

Suggested sequence for general anesthesia for cesarean section

Box 77-3

口試題目 9

67 歲男性病因為肝腫瘤來院做肝葉切除

手術,病人有高血壓,糖尿病,冠心動脈疾

病病史,手術二小時後心跳突然從

100/min下降到 50/min

一、 請問此時的處置是甚麼?若血壓為

60/40mmHg進一步處置為何?

二、假如還來不及用藥，心率即持續下降

至 10-20/Min，外科醫師回報手術視野血

液顏色變黑，此時的處置是?

三、經過十分鐘心肺復甦，心率 140/min,

血壓 60/30 mmHg， 此時的處置是甚麽?

參考答案

一、請問此時的處置是甚麼

參考答案: fig 108-10 p 3194

1. Bradycardia algorithm 流程, identify and treat underling

cause.

a. Check O2 pulse meter , EtCO2

b. EKG monitor rhythm ,type, rate, stable, or declining

c. 量血壓，檢查脈搏

d. 問外科醫師有無外科問題

e. 發生前的醫療處置用藥等

血壓量出來是 60/40 mmHg, 請問你使用何種藥物,Atropine, ephedrine,

epinephrine 不同藥物的考量是甚麼

二、假如還來不及用藥,心率持續下降至 10-20/Min,外科醫師回報手術視

野血液顏色變黑,此時的處置是

參考答案

Cardiac arrest algorithm, fig 108-19 P3201

分可電擊或不可電擊流程

三、經過十分鐘心肺復甦,心率 140/min, 血壓 60/30 mmHg

此時的處置是甚麽

1. 動脈導管，中央靜脈導管，作用分別是

2. 鑑別診斷是 5Ts, 5Hs 分別是甚麼，如何來排除及確立診斷

Box 108-4 p3203

3. Transesophageal echocardiography 的角色及運用是甚麽

口試題目 10

請說明上腹部手術後採用硬脊膜外腔術後止痛的藥物

(opioid or local anesthetics)可能造成的副作用及處

理方式。

參考答案

副作用主要來自 opioid and local anesthetic, Miller 列舉六項:

1. Hypotension.

The local anesthetics used in an epidural analgesic regimen may block sympathetic fibers

and contribute to postoperative hypotension.

處理: Strategies to treat noncritical hypotension caused by epidural analgesia include

decreasing the overall dose of local anesthetic administered (by decreasing the rate or

concentration), infusing an opioid epidural alone because it is unlikely that neuraxial

opioid administration would contribute to postoperative hypotension, and treating the

underlying cause of the decrease in blood pressure

2. Motor Block.

Use of local anesthetics for postoperative epidural analgesia may also contribute to lower

extremity motor block in approximately 2% to 3% of patients, and this may lead to the

development of pressure sores in the heels.

處理: A lower concentration of local anesthetic and catheter-incision–congruent

placement (放在符合手術部位的 level) of epidural catheters for abdominal or thoracic

procedures may decrease the incidence of motor block

3. Nausea and Vomiting.

Nausea and vomiting associated with neuraxial administration of single-dose opioid occurs

in approximately 20% to 50% of patients, and the cumulative incidence in those receiving

continuous infusions of opioid may be as high as 45% to 80%.

處理: Use of fentanyl alone or in combination with a local anesthetic in an epidural

infusion is associated with a lower incidence of nausea and vomiting than infusions of

morphine are. A variety of agents have been used successfully to treat neuraxial opioid–

induced nausea and vomiting, including naloxone, droperidol, metoclopramide,

dexamethasone, ondansetron, and transdermal scopolamine.

4. Pruritus.

Pruritus is one of the most common side effects of epidural or intrathecal administration of

opioids.

處理: Use of an epidural infusion of fentanyl alone or as part of a local anesthetic–opioid

combination appears to generally be associated with a lower incidence of pruritus.

Intravenous naloxone, naltrexone, nalbuphine, and droperidol appear to be efficacious for

the pharmacologic control of opioid induced pruritus

5. Respiratory Depression.

Neuraxial opioids used in appropriate doses are not associated with a higher incidence of

respiratory depression than that seen with systemic administration of opioid. Neuraxial

lipophilic opioids are thought to cause less delayed respiratory depression than

hydrophilic opioids are, although administration of lipophilic opioids may be associated

with significant early respiratory depression.

處理: Treatment with naloxone (and airway management if necessary) is effective in 0.1- to

0.4-mg increments.

6. Urinary Retention.

Urinary retention associated with the neuraxial administration of opioids is the result of an

interaction with opioid receptors in the spinal cord that decreases the detrusor muscle’s

strength of contraction.

處理: Urinary retention does not appear to depend on the opioid dose and may be treated

with the use of low-dose naloxone, though at the risk of reversing the analgesic effect.

Epidural administration of local anesthetics is also associated with urinary retention, with

a reported rate of approximately 10% to 30%.