Intensive intraoperative insulin therapy versus conventional glucose management during cardiac surgery: a randomized trial.
BACKGROUND
It is not known whether rigorous intraoperative glycemic control reduces death and morbidity in cardiac surgery patients.


OBJECTIVE
To compare outcomes of intensive insulin therapy during cardiac surgery with those of conventional intraoperative glucose management.


METHODS
A randomized, open-label, controlled trial with blinded end point assessment.


METHODS
Tertiary care center.


METHODS
Adults with and without diabetes who were undergoing on-pump cardiac surgery.


METHODS
The primary outcome was a composite of death, sternal infections, prolonged ventilation, cardiac arrhythmias, stroke, and renal failure within 30 days after surgery. Secondary outcome measures were length of stay in the intensive care unit and hospital.


METHODS
Patients were randomly assigned to receive continuous insulin infusion to maintain intraoperative glucose levels between 4.4 (80 mg/dL) and 5.6 mmol/L (100 mg/dL) (n = 199) or conventional treatment (n = 201). Patients in the conventional treatment group were not given insulin during surgery unless glucose levels were greater than 11.1 mmol/L (>200 mg/dL). Both groups were treated with insulin infusion to maintain normoglycemia after surgery.


RESULTS
Mean glucose concentrations were statistically significantly lower in the intensive treatment group at the end of surgery (6.3 mmol/L [SD, 1.6] [114 mg/dL {SD, 29}] in the intensive treatment group vs. 8.7 mmol/L [SD, 2.3] [157 mg/dL {SD, 42}] in the conventional treatment group; difference, -2.4 mmol/L [95% CI, -2.8 to -1.9 mmol/L] [-43 mg/dL {CI, -50 to -35 mg/dL}]). Eighty two of 185 patients (44%) in the intensive treatment group and 86 of 186 patients (46%) in the conventional treatment group had an event (risk ratio, 1.0 [CI, 0.8 to 1.2]). More deaths (4 deaths vs. 0 deaths; P = 0.061) and strokes (8 strokes vs. 1 strokes; P = 0.020) occurred in the intensive treatment group. Length of stay in the intensive care unit (mean, 2 days [SD, 2] vs. 2 days [SD, 3]; difference, 0 days [CI, -1 to 1 days]) and in the hospital (mean, 8 days [SD, 4] vs. 8 days [SD, 5]; difference, 0 days [CI, -1 to 0 days]) was similar for both groups.


CONCLUSIONS
This single-center study used a composite end point and could not examine whether outcomes differed by diabetes status.


CONCLUSIONS
Intensive insulin therapy during cardiac surgery does not reduce perioperative death or morbidity. The increased incidence of death and stroke in the intensive treatment group raises concern about routine implementation of this intervention.
Gandhi
Gunjan Y
GY
Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA. gandhi.gunjan@mayo.edu
Nuttall
Gregory A
GA
Abel
Martin D
MD
Mullany
Charles J
CJ
Schaff
Hartzell V
HV
O'Brien
Peter C
PC
Johnson
Matthew G
MG
Williams
Arthur R
AR
Cutshall
Susanne M
SM
Mundy
Lisa M
LM
Rizza
Robert A
RA
McMahon
M Molly
MM
D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D006348:Cardiac Surgical Procedures; D048909:Diabetes Complications / Q000517:prevention & control*; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000627:therapeutic use*; D007332:Insulin Infusion Systems; D007430:Intraoperative Care; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000517:prevention & control*; D016896:Treatment Outcome
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin