Trial Outcomes & Findings for IV Acetaminophen as an Adjunct Analgesic in Cardiac Surgery (NCT NCT01544062)

NCT ID: NCT01544062

Last Updated: 2016-06-21

Results Overview

The 24 hour postoperative opioid consumption will be obtained from the electronic medication administration record and expressed in morphine equivalents.

• Recruitment status: COMPLETED
• Study phase: PHASE4
• Target enrollment: 68 participants
• Primary outcome timeframe: 24 hours after arriving in ICU
• Results posted on: 2016-06-21

Participant Flow

Participant milestones

Measure	IV Acetaminophen Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	Normal Saline Study subjects receiving placebo
Overall Study STARTED	33	35
Overall Study COMPLETED	33	35
Overall Study NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

IV Acetaminophen as an Adjunct Analgesic in Cardiac Surgery

Baseline characteristics by cohort

Measure	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	Normal Saline n=35 Participants Study subjects receiving placebo	Total n=68 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	25 Participants n=5 Participants	22 Participants n=7 Participants	47 Participants n=5 Participants
Age, Categorical >=65 years	8 Participants n=5 Participants	13 Participants n=7 Participants	21 Participants n=5 Participants
Sex: Female, Male Female	4 Participants n=5 Participants	12 Participants n=7 Participants	16 Participants n=5 Participants
Sex: Female, Male Male	29 Participants n=5 Participants	23 Participants n=7 Participants	52 Participants n=5 Participants
Region of Enrollment United States	33 participants n=5 Participants	35 participants n=7 Participants	68 participants n=5 Participants

PRIMARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data for 1 study subject in normal saline group.

The 24 hour postoperative opioid consumption will be obtained from the electronic medication administration record and expressed in morphine equivalents.

Outcome measures

Measure	Normal Saline n=34 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Postoperative Opioid Consumption	62.3 mg Standard Deviation 29.5	45.6 mg Standard Deviation 29.5

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data for 1 study subject in normal saline group.

48 hour postoperative opioid consumption will be obtained from the electronic medication administration record and expressed in morphine equivalents.

Outcome measures

Measure	Normal Saline n=34 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Postoperative Opioid Consumption	105.1 mg Standard Deviation 42.1	85.1 mg Standard Deviation 42.3

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data for 3 study subjects in normal saline group.

Pain scores at rest will be recorded on Numeric Rating Scale by nursing staff. The Numeric Rating Scale ranges from 0 to 10 (0 - no pain, 1-2-3 - mild pain, 4-5-6 - moderate pain, 7-8-9 - severe pain, 10 - worst pain imaginable).

Outcome measures

Measure	Normal Saline n=32 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Postoperative Pain Scores at Rest	3.9 units on a scale Standard Deviation 2.3	3.7 units on a scale Standard Deviation 2.3

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data on 2 study subjects in normal saline group.

Pain scores at rest will be recorded on Numeric Rating Scale by nursing staff. The Numeric Rating Scale ranges from 0 to 10 (0 - no pain, 1-2-3 - mild pain, 4-5-6 - moderate pain, 7-8-9 - severe pain, 10 - worst pain imaginable).

Outcome measures

Measure	Normal Saline n=33 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Postoperative Pain Scores at Rest	2.4 units on a scale Standard Deviation 2.2	2.0 units on a scale Standard Deviation 1.8

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data on 3 study subjects in normal saline group.

Pain scores at rest will be recorded on Numeric Rating Scale by nursing staff. The Numeric Rating Scale ranges from 0 to 10 (0 - no pain, 1-2-3 - mild pain, 4-5-6 - moderate pain, 7-8-9 - severe pain, 10 - worst pain imaginable).

Outcome measures

Measure	Normal Saline n=32 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Postoperative Pain Scores With Movement	6.3 units on a scale Standard Deviation 2.5	6.0 units on a scale Standard Deviation 2.5

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data on 2 study subjects in normal saline group.

Pain scores at rest will be recorded on Numeric Rating Scale by nursing staff. The Numeric Rating Scale ranges from 0 to 10 (0 - no pain, 1-2-3 - mild pain, 4-5-6 - moderate pain, 7-8-9 - severe pain, 10 - worst pain imaginable).

Outcome measures

Measure	Normal Saline n=33 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Postoperative Pain Scores With Movement	5.1 units on a scale Standard Deviation 2.9	4.6 units on a scale Standard Deviation 2.0

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data on 3 study subjects in normal saline group.

Wound hyperalgesia will be determined by testing the right side of the chest along five horizontal lines vertically separated by 2 cm at right angles to the incision using 180 gram von Frey filament (# 6.45).

Outcome measures

Measure	Normal Saline n=32 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Wound Hyperalgesia	4.8 cm Standard Deviation 4.3	4.5 cm Standard Deviation 3.8

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data on 2 study subjects in normal saline group.

Wound hyperalgesia will be determined by testing the right side of the chest along five horizontal lines vertically separated by 2 cm at right angles to the incision using 180 gram von Frey filament (# 6.45).

Outcome measures

Measure	Normal Saline n=33 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Wound Hyperalgesia	4.6 cm Standard Deviation 3.9	5.0 cm Standard Deviation 3.5

SECONDARY outcome

Timeframe: From the time of arrival in ICU until extubation

The length of mechanical ventilation will be determined based on the "Extubation Criteria" checklist that will be completed by nursing staff every 2 hours until extubation.

Outcome measures

Measure	Normal Saline n=35 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
Length of Mechanical Ventilation	407 minutes Standard Deviation 683	360 minutes Standard Deviation 276

SECONDARY outcome

Timeframe: From the time of arrival in ICU until ICU discharge

The length of ICU stay will be determined based on the "ICU Discharge Criteria" checklist that will be completed by nursing staff every 4 hours until ICU discharge.

Outcome measures

Measure	Normal Saline n=35 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
Length of ICU Stay	67 hours Standard Deviation 35	61 hours Standard Deviation 27

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Questionnaire not completed by 12 study subjects in normal saline group and 10 study subjects in IV acetaminophen group.

"The extent to which subjects overall pain experience met their expectations" question responses were converted to the Likert scale with the following values: not at all (1), a little (2), a fair amount (3), very much (4) and extremely well (5).

Outcome measures

Measure	Normal Saline n=23 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=23 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Patient Satisfaction	2.3 units on a scale Standard Deviation 1.2	2.8 units on a scale Standard Deviation 0.9

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of nausea was defined as numeric scale response 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=35 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Nausea	25 participants	26 participants

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of nausea was defined as numeric scale response 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=35 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Nausea	12 participants	14 participants

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data on 3 study subjects in normal saline group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of pruritus was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=32 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Pruritus	4 participants	7 participants

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data on 8 study subjects in normal saline group and 6 study subjects in IV acetaminophen group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of pruritus was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=27 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=27 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Pruritus	4 participants	7 participants

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data on 3 study subjects in normal saline group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of sedation was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=32 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Sedation	8 participants	8 participants

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data on 6 study subjects in normal saline group and 3 study subjects in IV acetaminophen group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of sedation was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=29 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=30 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Sedation	6 participants	3 participants

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data on 3 study subjects in normal saline group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of respiratory depression was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=32 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Respiratory Depression	2 participants	2 participants

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data on 6 study subjects in normal saline group and 3 study subjects in IV acetaminophen group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of respiratory depression was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=29 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=30 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Respiratory Depression	1 participants	0 participants

SECONDARY outcome

Timeframe: 24 hours after arriving in ICU

Population: Missing data on 3 study subjects in normal saline group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of dizziness was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=32 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=33 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
24 Hour Dizziness	20 participants	17 participants

SECONDARY outcome

Timeframe: 48 hours after arriving in ICU

Population: Missing data on 7 study subjects in normal saline group and 4 study subjects in IV acetaminophen group.

Opioid related adverse effects were recorded using a numeric scale (0 = no adverse effects, 1 = mild adverse effects not requiring treatment, 2 = moderate adverse effects requiring treatment and 3 = severe adverse effects refractory to treatment). Presence of dizziness was defined as numeric scale response 1 (mild adverse effects not requiring treatment), 2 (moderate adverse effects requiring treatment) or 3 (severe adverse effects refractory to treatment).

Outcome measures

Measure	Normal Saline n=28 Participants Study subjects receiving placebo Placebo: Total of 6 doses of 100 mL of normal saline at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.	IV Acetaminophen n=29 Participants Study subjects receiving IV acetaminophen IV acetaminophen: Total of 6 doses of 1,000 mg IV acetaminophen at the following time points: (1) immediately after anesthesia induction, but prior to the incision, (2) at the end of surgery with (3) four additional doses administered postoperatively in the ICU every 6 hours for the first 24 hours.
48 Hour Dizziness	9 participants	10 participants

Adverse Events

Normal Saline

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

IV Acetaminophen

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Srdjan Jelacic, MD

University of Washington

Phone: (206) 598-3777

Email: sjelacic@uw.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place