10. Targeted Temperature Management (TTM)

Question 1

Overview:

-TTM is a treatment that

Answer 1

lowers the pt’s core body temperature in order to prevent the neurological effects of an ischemic injury in the brain of survivors of sudden cardiac death.

Question 2

-Assess pts after cardiac arrest for

Answer 2

inclusion criteria and exclusion criteria (table 5-11)

Question 3

Inclusion Criteria for TTM use

Answer 3

-Cardiac arrest with a return of spontaneous circulation

-Unresponsive or not following commands after cardiac arrest

-Witnessed arrest with downtime of less than 60 minutes

Question 4

Exclusion Criteria for TTM Use

Answer 4

-Pregnancy

-Core Temperature of less than 35C

-Age < 18 or > 85

-Existing DNR status or terminal disease

-Chronic renal failure

-Sustained refractory ventricular arrhythmias

-Active bleeding

-Shock

-Hemodynamic Instability

-Drug intoxication

Question 5

TTM involves 3 phases:

Answer 5

1. Induction phase
2. Maintenance phase
3. Rewarming phase

Question 6

Induction phase

Answer 6

lowers the pt’s temperature to 32 - 36C (as ordered by the provider); start this cooling ASAP

-The RN should initiate this cooling within 90 min of pt going into arrest; the cooling may last for as long as 6 hrs after the arrest

Question 7

Maintenance phase

Answer 7

Keep the pt at the target temperature (32-36C) for 24 hrs.

Question 8

Rewarming phase

Answer 8

slowly increase the pt’s temp to 36.5-37C (as ordered by the provider)

Question 9

During the Induction Phase (RN implications):

Answer 9

-Set the goal time to the target temperature

-Monitor the core temperature (via pulmonary artery catheter, esophageal, bladder, rectal).

-Apply the device (external pads or internal central venous catheter)

-The goal systolic BP is generally > 90 mmHg, and the goal MAP is > 70 mmHg.

-Obtain baseline labs and generally complete a metabolic panel, a complete blood count, a coagulation panel, a check of the pt’s serum magnesium and phosphorus levels, and an arterial blood gas.

-Get a baseline bedside blood glucose measurement.

-Obtain a 12-lead ECG

-Initiate deep sedation

-Manage shivering by covering the head, hands, and feet or by using meperidine (Demerol); use a neuromuscular agent if shivering is not controlled with meperidine (Demerol)

-Monitor/manage the systemic effects of hypothermia.

Question 10

Systemic Effects of Hypothermia

Answer 10

-Insulin resistance —-> hyperglycemia
-Electrolyte and fluid shifts
-Shivering
-Skin breakdown
-Pupil and corneal reflexes may be absent due to hypothermia
-Decreased cardiac output
-Up to 25%
-Alteration in coagulation
-Platelet dysfunction
-Increased risk for infection
- Neutrophil and macrophage functions decrease at temperatures less than 35C.

Question 11

Maintenance Phase (Duration 24 hours) (RN implicat.)

Answer 11

-Continuously monitor the core temp (bladder, rectal); the core temp should not be lower than the specified goal (32-36C)

-Monitor VS (at least hourly)

-Obtain routine bedside blood glucose measurements and initiate an insulin drip as needed.

-Monitor train-of-four (TOF) every hour if a paralytic is used and ensure a goal of 1-2 twitches to prevent prolonged paralysis.

-Repeat labs (same as baseline labs) every 8 hours until the pt is rewarmed.

Question 12

Rewarming phase (RN implications)

Answer 12

-Perform passive rewarming to 36.5-37C.

-Program the cooling unit to increase the target temperature by 1 degree per hour.

-Stop all potassium administration 8 hours prior to rewarming.
-Rewarming causes rebound hyperkalemia.

-Discontinue paralytics (if they were being used) after the pt is warmed to 36.5 C

-Repeat labs (same as baseline) when the pt is rewarmed

-Perform a close neurological assessment, pupil and corneal reflexes may continue to be absent for a time.