Postoperative delirium after coronary artery bypass graft surgery: Dexmedetomidine infusion alone or with the addition of oral melatonin

Abstract

Introduction: Postoperative delirium is a common complication of cardiac surgery. This study aimed to assess the effect of supplementing dexmedetomidine infusion with oral melatonin in prevention of postoperative delirium after coronary artery bypass graft surgery. Methods: 110 patients of both sexes above 60 years of age were included. Anesthetic management was standardized. Patients were randomly allocated into one of the two study groups, dexmedetomidine/melatonin (DM) group or dexmedetomidine (D) group. Patients in the DM group received oral Melatonin tablet 5 mg the night before surgery and same dose was repeated every 24 hours for 3 postoperative days. After completion of surgery and upon ICU arrival, patients in both groups received a bolus of 0.4 µg/kg dexmedetomidine followed by 0.2-0.7 µg/kg/h infusion, for 24 maximum hours. Delirium was assessed for 5 days postoperatively at 12 hr intervals using confusion assessment method (CAM) for ICU and after discharge from ICU to surgical ward using CAM. Delirious patients were treated with IV haloperidol. Results: No significant differences between studied groups regarding baseline, preoperative, intraoperative and postoperative characteristics. Incidence of delirium was significantly lower, onset significantly more delayed, and duration was significantly shorter in group-DM as compared to group-D. No significant differences between all cases, cases who had delirium, and cases who did not have delirium in the two groups as regards extubation time, ICU stay, and hospital stay. Conclusion: supplementing dexmedetomidine with melatonin decreases incidence, delays onset, and shortens duration of postoperative delirium in patients above 60 years of age undergoing CABG surgery.

Melatonin and Its Analogs for Prevention of Post-cardiac Surgery Delirium: A Systematic Review and Meta-Analysis

“…The interventions used included ramelteon 8 mg in two studies ( 31 , 34 ) and melatonin 3 mg or 5 mg in eight studies ( 19 – 22 , 29 , 30 , 32 , 33 ). Nine studies ( 19 – 21 , 29 – 34 ) included 1,417 patients who underwent cardiothoracic surgery, such as coronary artery bypass graft surgery, aortic valve replacement, mitral valve replacement, and elective pulmonary thromboendarterectomy. A total of 297 patients underwent percutaneous transluminal coronary intervention ( 22 ).…”

“…Of the eight RCTs ( 19 – 22 , 29 – 32 ), six were classified as low-risk ( 19 , 20 , 22 , 30 – 32 ), and one was classified as being associated with “some concern” because the randomization process could not be blinded ( 21 ). The other study was also classified as being associated with “some concern” owing to deviations from intended interventions and outcome measurements ( 29 ) ( Supplementary Table 2 ).…”

“…Figure 4 shows the secondary outcomes of this study. Six studies ( 19 , 21 , 29 , 31 , 33 , 34 ) (1,017 participants) reported the duration of postoperative mechanical ventilation, and the meta-analysis showed that mechanical ventilation time was not significantly shortened following melatonin or ramelteon administration (SMD, −0.03; 95% CI, −0.15 to 0.10; P = 0.60; Figure 4A ). A meta-analysis of seven studies ( 19 , 21 , 29 , 31 , 33 , 34 ) (1,017 patients) reported that melatonin or ramelteon administration did not significantly shorten the length of ICU stay (SMD, −0.12; 95% CI, −0.33 to 0.09; P = 0.06; Figure 4B ).…”

“…Six studies ( 19 , 21 , 29 , 31 , 33 , 34 ) (1,017 participants) reported the duration of postoperative mechanical ventilation, and the meta-analysis showed that mechanical ventilation time was not significantly shortened following melatonin or ramelteon administration (SMD, −0.03; 95% CI, −0.15 to 0.10; P = 0.60; Figure 4A ). A meta-analysis of seven studies ( 19 , 21 , 29 , 31 , 33 , 34 ) (1,017 patients) reported that melatonin or ramelteon administration did not significantly shorten the length of ICU stay (SMD, −0.12; 95% CI, −0.33 to 0.09; P = 0.06; Figure 4B ). A pooled analysis of six studies ( 21 , 22 , 30 , 31 , 33 , 34 ) (1,319 participants) showed no significant shortening of the length of hospitalization following melatonin or ramelteon administration (SMD, 0.03; 95% CI, −0.25 to 0.32; P < 0.001, Figure 4C ).…”

“…A meta-analysis of seven studies ( 19 , 21 , 29 , 31 , 33 , 34 ) (1,017 patients) reported that melatonin or ramelteon administration did not significantly shorten the length of ICU stay (SMD, −0.12; 95% CI, −0.33 to 0.09; P = 0.06; Figure 4B ). A pooled analysis of six studies ( 21 , 22 , 30 , 31 , 33 , 34 ) (1,319 participants) showed no significant shortening of the length of hospitalization following melatonin or ramelteon administration (SMD, 0.03; 95% CI, −0.25 to 0.32; P < 0.001, Figure 4C ). A subgroup analysis following melatonin and ramelteon administration revealed no significant intergroup differences in any of the secondary outcomes.…”