Surgical Procedures/Special Populations Flashcards
Tonsillectomy is associated with.
severe pain,
Adenoidectomy is associated with
minimal pain
Up to 65% of patients undergoing tonsillectomy experience
postoperative vomiting.
LMA’s were first described for use in
tonsillectomy in 1990 and are especially useful for preventing exposure of the lower airway to blood.
What type of patient injury could occur if intravenous lines are allowed to lie in a coil in the MRI suite?
Burn
It is important to keep devices such as intravenous lines or ECG monitor wires straight during an MRI. Any coiled objects can induce
a current and cause a burn.
A patient presenting for carotid endarterectomy has amaurosis fugax. You know that this is
monocular blindness
You are performing anesthesia for a patient undergoing a total hip replacement. The surgeon is using polymethylmethacrylate to cement the prosthetic in place. You know that polymethylmethacrylate will result in
intramedullary hypertension
Intramedullary HTN cause
This can produce hypoxia, hypotension, dysrhythmias, and pulmonary hypertension. The circulating cement can also produce a decrease in systemic vascular resistance and a subsequent decrease in blood press
The onset of all muscle relaxants is significantly longer in elderly patients why?
Because of decreased cardiac output, longer circulatory time, and decrease in skeletal muscle blood flow,
Which of the following laboratory values tends to be decreased in full-term parturients?
ALBUMIN
Upon which of the following actions should you place the highest priority prior to commencing intravenous sedation for a patient undergoing an MRI?
Establishing a means for communicating with the MRI technician during the procedure
Oxygen consumption increases by about The plasma base (HCO3-) decreases from about 26 to 22 mEq/L, thus, the pH is essentially unchanged.
33 percent in the full-term parturient, but minute ventilation increases by 50 percent at term.
The increased alveolar ventilation in full term parturients results in an
increase in the PaO2 to about 106 mmHg and a decrease in the PaCO2 to about 30-32 mmHg.
Geriatric patients and fat?
increased adipose stores, which prolongs the action of lipid-soluble drugs.
Geriatric hepatic and renal blood flow
They also have decreased hepatic and renal blood flow which can prolong the action of drugs dependent on the liver and kidneys for elimination.
Protein normally are not affected by aging.
Alpha-1 acid glycoprotein levels
Although elderly they have a_____ vascular volume, this correlates with a
decreased ; higher initial plasma concentration of a drug, not a prolonged elimination half-life.
Extravasation of the cement in vertebroplasty vs kyphoplasty?
Vertebroplasty is more likely to result in extravasation of the cement because the cement used in vertebroplasty is less viscous than that used for kyphoplasty.
Potential neurologic complications of vertebroplasty.
Radiculopathy, spinal claudication, and paraplegia
After Vertebroplasty The patient should be .
The patient is positioned prone for the actual procedure and should remain supine for 3-5 hours after the procedure for evaluation of neurologic status and careful observation for bleeding
Vertebroplasty, kyphoplasty and anesthetics
General anesthesia and IV sedation are both acceptable techniques for these procedures.
A patient undergoing carotid endarterectomy exhibits profound bradycardia (23 bpm) which is successfully treated with atropine. To prevent a recurrence of this event, you should
ask the surgeon to infiltrate the carotid sinus area with lidocaine
CEA: Bradycardia may be caused by manipulation of
baroreceptors in the carotid sinus.
Following carotid endarterectomy, it is important to maintain the systolic blood pressure below what value to prevent an increased incidence of stroke, TIA, and myocardial infarction?
180 mmHg
You are preparing to perform a penile block for a patient undergoing surgical repair of hypospadius. You know that the principal nerve supply to the penis is provided by the
. pudendal nerve
How does obesity affect the pharmacokinetics of midazolam?
It increases the volume of distribution
Obesity : How do you dose midazolam for single IV dose vs continuous infusion dose?
A single intravenous dose should be based on total body weight, but a continuous infusion should be based on lean body weight.
Why is pancuronium clearance increase in the elderly?
The elimination of pancuronium is prolonged in the elderly, but since it is eliminated primarily via the renal route, it is the decrease in renal clearance, not hepatic clearance that prolongs pancuronium.
The O’Brien and Nadbath blocks are used to prevent movement of the eyelids during ocular surgery. A side effect of both of these blocks is
Unilateral facial paralysis
Select two physiologic changes associated with obesity.
Increased renal tubular reabsorption
Increased glomerular filtration rate
Obesity is characterized by an
increased glomerular filtration rate, increased renal tubular resorption, and impaired sodium excretion which further worsens hypertension.
Congenital diaphragmatic hernia occurs in about_____live births.
1:2000
Congenital diaphragmatic hernia In about 90 percent of cases, the herniation occurs on the and can result in
left side through the foramen of Bochdalek
Congenital diaphragmatic hernia results in
D-CRACS diminished breath sounds on the affected side Cyanosis Respiratory distress apparent dextrocardia, cardio-respiratory failure, scaphoid abdomen
Congenital diaphragmatic hernia what should be placed?
A nasogastric tube should be placed to prevent further gastric distention.
What should be avoided in congenital diaphragmatic hernia and why?
Positive pressure ventilation by mask should be avoided as it can result in stomach inflation and worsen mediastinal displacement.
The degree of fatty liver infiltration seen in obese patients is primarily related to
. the length of time the patient has been obese
It should be noted that fatty infiltration is not affected by the degree of obesity in liver . Rather, it is a
reflection of the length of time one has been obese.
Severely obese patients often have elevated liver enzymes.
Alanine aminotransferase
Which enzyme is elevated due to the blockage of bile canaliculi by triglyceride depositions?
Clearance of drugs is usually not reduced, however.
Abnormal liver function tests are present in about
1/3 of morbidly obese individuals.
Is the most common abnormality
Increased alanine aminotransferase
What is the only local anesthetic that is metabolized rapidly enough to avoid substantial accumulation in the fetus?
Chloroprocaine
How is a patient positioned for splenectomy?
Lateral decubitus
Hepatic function and neonate?
Hepatic function is immature in the newborn and some hepatic pathways do not mature until after a year of age.
Albumin and neonates
Levels of albumin and other serum proteins are low in the full-term infant and result in a higher free fraction of many protein-bound drugs.
Which of the following characteristics are consistent in a neonate with congenital diaphragmatic hernia? (select two)
Lung hypoplasia and tachypnea
The initial presentation of Congential Diaphragmatic Hernia is.
respiratory distress due to lung hypoplasia with tachycardia and tachypnea being present at birth
In congenital diaphragmatic hernia, the compression of the
Compression of the vena cava by the intestines can also produce reduced preload and a corresponding decrease in cardiac ouput. The abdomen may appear scaphoid due to its contents being extruded into the thorax.
The most commonly used strategy for fluid resuscitation is to take the
percent of body surface area burned, multiply it by 2-4 times the weight in kilograms, and administer that volume during the first 24 hours following the burn.
You are caring for a patient about to undergo anesthesia for a cesarean section. You assist her into the supine position on the surgical table. She soon experiences hypotension, tachycardia, dizziness, and nausea. What first action should you take?
Place in left lateral tilt position
When placing monitors on a patient presenting for mediastinoscopy, which of the following is the most appropriate arrangement?
Radial arterial line and O2 saturation monitor on the right arm and the blood pressure cuff on the left arm
During mediastinoscopy, there is a significant risk of compression of the i
Innominate artery by a mediastinal mass or by the mediastinoscope itself resulting in a drop in right arm blood pressure. If only the right arm blood pressure is monitored, the patient may be treated inappropriately for hypotension. If only the left arm is monitored, the obstruction may go unnoticed. If the pressure in the right arm is less than that of the left arm, you should suspect innominate vessel compression. Placing the arterial line and O2 saturation monitor on the right arm will detect compression of the artery sooner.
Pain that follows the distribution of a nerve or group of nerves is referred to as
Neuralgia
A patient exhibits persistent postoperative hoarseness following an anterior cervical disk fusion. A possible cause is damage to the _____ nerve from the retractors.
RLN
The symptoms of an amniotic fluid embolism include:
sudden shortness of breath, hypoxia, cyanosis, and severe hypotension.
Following an open colon resection, a patient exhibits liver enzymes that are twice the normal value. You know that this
is common and typically resolves in 48 hours
Patients who suffer a myocardial infarction following noncardiac surgery have an elevated in-hospital mortality rate of
15-25%
In fact, is an independent predictor of death in the 6 months after the surgery.
a perioperative myocardial infarction
Which change is principally responsible for the reduction in alveolar surface volume in the elderly?
Decreased pulmonary elastic tissue
All of the following ventilatory parameters remain unchanged in pregnancy
Lung compliance
Deadspace volume
Total lung capacity
CDH is associated what type of abdomen
SCAPHOID
In which Rexed lamina are second-order wide dynamic range neurons found?
Lamina V
Which of the following statements regarding the hematology studies of a full-term parturient is correct?
The red blood cell mass increases
What is the maximum recommended aspirant amount in an office based liposuction procedure?
5000 ml
Which of the following is greater in a healthy two year-old patient than it is in an adult? (select two)
Protein binding is decreased in preterm and term infants but is similar between children and adults. The bioavailability of ketamine is high in adults (93%) but is even higher in children.
Vd of propofol children vs adults
The volume of distribution of propofol is larger in children than adults.
By 6-12 months of age, the clearance of morphine is
equal to that of adults.
You are performing a preoperative assessment on a full-term parturient being admitted for scheduled cesarean section. She states that her physician told her she had hydronephrosis, but that he told her not to worry about it.
You should reassure her that hydronephrosis is common in pregnancy
The incidence of hydronephrosis in pregnant women?
80% in pregnant patients.
Hydronephrosis in pregnancy and why? what are increase
The increased blood and interstitial volume produce a compensatory increase in renal volume. The urinary collecting system (collecting ducts, calcyes, renal pelvis, and ureters) dilate substantially, producing hydronephrosis in 80% of pregnant women by
What would be considered an advantage of combined spinal-epidural analgesia?
It is highly effective when initiated during fast progressing labor
Which electrolyte disorder would be most likely to worsen cerebral edema following a craniotomy?
Hyponatremia causes the extracellular fluid to become hypotonic. As this occurs, water begins moving into the brain cells causing cerebral edema and intracranial hypertension.
You are preparing to perform a general anesthetic for a patient undergoing a CT scan. Which of the following statements is true?
PEEP should be applied in pediatric patients to improve scan visibility
Studies have demonstrated that CT scans performed on children using general anesthesia resulted in what ? What can prevent is from happening? Pregnancy is a
atelectasis severe enough to obscure evidence of metastasis on the scan. Adding 5 cm H2O of PEEP was sufficient enough to prevent this from occurring.
Contraindication to the administration of intravenous contrast media.
Pregnancy
CT scan with contrast: LMA what is the exception?
General anesthesia can be performed with an LMA if the patient has no contraindications.If the patient has received oral contrast, however, an endotracheal tube must be used to prevent aspiration.
Which of the following is true of CO2 lasers?
They can melt steel
A CO2 laser is.
infrared and emits primarily as heat
It can melt almost any structure upon which it is focused, including steel.
CO2 laser
Because the CO2 laser is greatly absorbed by water, Vaporization of tissues usually occur when?
the vaporization of tissues usually occurs within the first 200 micrometers of tissue depth.
CO2 laser and water absorption
is greatly absorbed by water,
Because it has very limited thermal effect on surrounding tissues, the_______ laser is better suited for LASIK surgery, the ____laser is not.
excimer; CO2
Not suited for LASIK surgery
CO2 laser.
Effects of mannitol when administered during vascular surgery
- Mannitol increases urine output during aortic cross-clamp, but this effect has not been shown to alter renal outcomes after surgery involving aortic cross-clamping. – serve as a free radical scavenger which may be of benefit after the release of the aortic cross-clamp.
Increases prostaglandin synthesis which causes renal vasodilation.
You are performing general anesthesia for a morbidly obese patient undergoing laparoscopic surgery. Which of the following is more likely to occur in this patient than in a patient of normal weight?
The endotracheal tube will become displaced
Which location would be least appropriate for placement of an arterial line in a patient undergoing surgery on the distal aortic arch?
LEFT WRIST. Because the left subclavian artery may be manipulated during the operation, which would disrupt monitoring in the left radial artery, monitoring pressures via another site would be preferred. The right radial is often used.
Rubbing the skin of a painful area decreases the sensation of pain according to what pain control theory?
Gate CONTROL THEORY
According to the gate control theory of pain,. Rubbing the skin activates A-beta fibers, which are faster than the A-delta and C fibers carrying the pain transmission.
pain can be transmitted to the supraspinal regions of the brain if the gate is open. If the pain pathway is competing with other types of stimulation, the gate may be closed to the painful stimuli, and it wouldn’t be felt
An example is rubbing the skin over a painful area.
Gate control theory
The A-beta fibers override
some of the pain messages and close the gate, decreasing the sensation of pain.
The primary function of von Willebrand factor is
o promote platelet aggregation and adhesion to collagen
The composition of the inspired gas mixture delivered to the patient is dependent upon all of the following except
CO of the patient
Filtration fraction is the a.
ratio of the glomerular filtration rate to renal plasma flow, and it is normally about 20%.
The glomerular filtration rate is dependent on the relative
tone of the afferent and efferent arterioles in the nephron.
What increase filtration fraction?
an increase in the diameter of the afferent arteriole
a decrease in the diameter of the efferent arteriole
An increase in the diameter of the afferent arteriole (vasodilation) or a decrease in the diameter of the efferent arteriole (vasoconstriction) will increase the filtration fraction and vice vers
The changes in the tone of these arterioles can maintain a steady glomerular filtration rate between mean arterial
pressures of 80 and 180 mmHg.
Which of the following clinical signs are consistent with a diagnosis of hypothyroidism? (select four)
pressure-controlled ventilation
With laparoscopic surgeries hospitalizations are______ recovery _____ pain_______, and pulmonary function are
shorter ; faster; less pain: pulmonary function better preserved
Preferred anesthetic for Laparoscopic surgery is
General anesthesia with cuffed ET. due to discomfort of a pneumoperitoneum, positioning, length of surgical time and hypercarbia.
Early ambulation and return to normal activities associated with open vs lap surgeries
Laparoscopic surgeries
How is a pneumoperitoneum created?
When CO2 is insufflated into the peritoneal cavity.
Vascular injury during trocar insertion can be diagnosed directly and immediately by
Bleeding through the laparoscope.
What suggest intravascular injury after trocar insertion>
Refractory hypotension and tachycardia
Venous return and High IAPs
Decreased venous return.
How does the pneumoperitoneum affect pulmonary compliance?
Pulmonary compliance is reduced by 30-50%
The reduction of pulmonary compliance on minute ventilation
The minute ventilation needed to avoid hypoxemia and hypercarbia is increased
With pneumoperitoneum , the increase in PAW and plateau pressure is due to
Diaphragmatic elevation and increased IAPs.
What are the 4 common complications that can happen abruptly during insufflation of the peritoneal cavity
Subcutaneous emphysema
Pneumothorax
Endobronchial intubation
Gas embolization
What causes subcutaneous emphysema during laparoscopic surgery?
When the insufflation needle is poorly stabilize and not completely in the peritoneal cavity. Gas accumulates between fascia and peritoneum
Signs of subcutaneous emphysema during laparoscopic surgery
Rise in PEtCO2 and crepitus along fascia planes in head, neck and abdomen
What can cause pneumothorax with laparoscopic surgery?
Pressurized gas goes into the pleural cavity .
Large pressurized gas to the pleural cavity can lead to a tension affect causing: what happens to
BP, HR, PAW, capnograph, EtCO2.
hypoxia Hypotension Tachycardia High PAW Obstructive pattern on capnograph Decreased PEtCO2 as Cardiac Output is compromised
With a patient with a small pneumothorax what can be done
conservative management if stable and pneumothorax is small because time and manual positive pressure will re-expand the lung.
What is a capnothorax?
CO2 Pneumothorax that occur during laparoscopy
Signs and symptoms of capnothorax
worsening obstructive pattern on capnography
Progressive increase in PAW
increasing PEtCO2
Action to take with capnothorax?
Alert surgeon to release pneumoperitoneum
Chest xray
Endobronchial intubation occuring with laparoscopic surgery is due to
Cephalad movement of the diaphragm due to pneumoperitoneum and head-down positioning.
Prolonged endobronchial intubation lead to
desaturation and increased PAW
A gas embolism can occur after
Trocar or veress needle is inadvertently inserted into a vein or into an abdominal organ and CO2 insufflated
Large gas embolism will result in
Large physiologic dead space
decrease EtCO2
Hypoxia
hypotension and eventually cardiac arrest
Gas embolism first action
CO2 insufflation stopped FiO2 100% stop nitrous increase MV, PEEP place patient in LEFT LATERAL and TRENDELENBURG POSITION
Intraabdominal pressure should never exceed
15 mmHg
Exceeding 15mmhg of insufflation can lead to
increase intrathoracic pressure
Increase Co2 tension,
Physiologic dead space.
During insufflation, stretching of the peritoneum can cause
A rapid vagal-mediated bradycardia and even asystole.
Treatment of insufflation mediated vagal bradycardia is
immediate release of pneumoperitoneum even asystole.
Administration of an anti-muscarinic can be helpful
MAP , CI with pneumoperitoneum
Increased by 35%
CI is decreased by as much as 50%
Pneumoperitoneum and immune
Pneumoperitoneum lead to a release of humoral factors such as catecholamines, prostaglandins, the RAAS and vasopressin
Vasopressin and IAP
fivefold increase in vasopressin levels at an IAP of 10 mmHg
What are the major implications of pneumoperitoneum>? CO, MAP, PVR,
Decreased CO MAP unchanged or increased increased PVR Increased SVR Increase neuroendocrine response Possible bradycardia/asystole from vagal stimulation
Very high IAP > 15 mmHg on intrathoracic pressure
Limiting venous return
Why is arrhythmia associated with pneumoperitoneum?
Bradycardia / asystole from peritoneal stretching.
During insufflation of the peritoneum, the PaCo2 will
Increase and reach a plateau after 15-30 minutes
What is the primary mechanism of increased PaCo2 with insufflation?
Absorption of Co2 from the peritoneal cavity.
Correction of increased PaCo2 with insufflation can be achieved by
an increase in alveolar ventilation
With patients with impaired CO2 excretion capacity such as COPD or cyanotic heart disease there is not a ____. What shoud be obtained.
reliable correlation between PaCo2 and ETCO2.
Obtain arterial blood sampling
Top differential diagnosis of hypercarbia during laparoscopy?
Prolonged laparoscopy (surgical times)
IAP > 15mmhg due to enlargment of resp dead space
Inadequate minute ventilation
Lap cholecystectomy position is
RT or head up position
Lap Hysterectomy position is
Trendelenburg or head down position
What is the goal of positioning with laparoscopic procedures?
For gravity to displace the abdominal viscera away from the surgical location .
Pneumoperitoneum and CO
Decreases CO.
Pneumoperitneum and lung
Decreased lung compliance and volume
CV changes with a trendelenburg position
effect on healthy patients?
Increased central blood volume to the right heart
Increased CO
(insignificant in healthy)
CV changes effect of trendelenburg position with patient with cardiac issues
Increase myocardial oxygen demand
acute heart failure.
Pulmonic changes of the head down position are
decreased vital capacity
FRC
compliance
Tendency of post-op atelectasis.
