Positioning&Thermal Regulation - Dr. Reed's Final Review Flashcards
Arms should be less than _____ degrees or tucked in the supine position.
90 degrees
My arm is abducted while lying supine; what nerve is most commonly injured because of pressure in the OR?
Ulnar Nerve
If the Ulnar Nerve is injured, how will it manifest symptomatically?
Claw Hand
Inability to abduct or oppose the 4th and 5th digit. Diminished sensation of the medial side of fingers. Claw-like appearance over time.
A: Claw Hand - Bent 4th and 5th digits. Sensory deficit in 4th and 5th digit.
What can impede venous return?
High PEEP
Positive Pressure Ventilation
Increased Intrathoracic Pressure
Systemic Vasodilation - Blood pooling in dependent areas
Neuromuscular Blocking Agents - normal muscle tone impaired
What sort of things can alter patients’ normal compensatory mechanisms?
Anesthetic medications result in myocardial depression and vasodilation. NMBs decrease muscle tone, which can also cause blood pooling in dependent areas. GA blunts compensatory mechanisms to increase heart rate and SVR.
When we decrease venous return, what kind of problem is that?
Preload problem, which decreases stroke volume and decrease cardiac output
Most commonly injured nerve in the supine position
Ulnar Nerve and Brachial Plexus
Patients at high risk for postoperative vision loss are those in which positions
Lengthy procedures in the prone or steep Trendelenburg position (Per Dr. Reed - sitting position as well from hypotension optic ischemia)
Most commonly injured nerve in the prone position
Optic Nerve or Spinal Cord
Most commonly injured nerve in the lithotomy position
Common Peroneal Nerve (common fibular nerve)
Most commonly injured nerve in the lateral decubitus position
Brachial Plexus!, Suprascapular, Long Thoracic, Peroneal and Radial
What position has the highest risk for Venous Air Embolism?
Sitting position
You’re seeing a patient post-op with a chief complaint about their hand(s); , along with the common etiology if it was the Median Nerve what symptoms would be present
Etiology: Extension of elbow beyond the normal range. IV placement error/damage
Chief Complaint: Hand of Benediction, Inability to make a fist. Decreased sensation of the thumb, index, and middle finger plamer side
You’re seeing a patient post-op with a chief complaint about their hand(s); what nerve has been injured, along with the common etiology if it was the Ulnar Nerve
Ulnar nerve compressed against posterior aspect of medial epicondyle of humerus.
You’re seeing a patient post-op with a chief complaint about their hand(s); what nerve has been injured, along with the common etiology if it was the Radial Nerve
Etiology: Arm pressed against a vertical position or retractor post or pole. Intraop use of tourniquets. Frequent blood pressure cycling.
Complaint: Wrist drop (can’t dorsal flex), inability to extend metacarpal joints, weakness of abduction of the thumb, index, and middle finger.
A patient has a problem with making a fist. What nerve and etiology has occurred?
Median Nerve. Hand of Benediction(index and middle) or Ape Hand (thumb)
Can’t make a fist.
When does most of the patient’s heat loss occur in the OR?
Within the first hour
By what mechanism is most heat loss occurring during that first hour?
Radiation
Describe conduction heat loss
Heat loss by physical contact. A warmer object comes into contact with a cooler object.
Describe convection heat loss
Heat loss by cool air passing a warmer surface
Describe radiation heat loss
Heat, like body heat, escapes into the cooler environment
Describe heat loss via redistribution
Redistribution of cold blood to the central compartment
Shoulder Operation in the sitting position. What are some of the risks associated with that position?
- Optic Nerve ischemia. After load drops after induction. Going from supine to sitting forces blood away from the head/eyes, causing ischemia. (Dr. Reed: Likes SBP>105 and MAP= 70 or more)
- Air embolus due to an open venous sinus above the heart. As the ventricles open and the atria empty, we create negative pressure, which can entrain air.
The patient presents with foot drop; what nerve is injured?
The common peroneal nerve.
What are the risks associated with intraoperative hypothermia?
Increased oxygen consumption through shivering
Increased cardiovascular incidents and MI
Interference with coagulation (impairing platelet function, slowing clot formation, slowing coagulation enzyme activity, and enhancing fibrinolysis)
Wound infection and delayed healing
Increased rate of sickling in SCD
Prolonged PACU stays
