Cardiovascular Safety of Clonidine and Dexmedetomidine in Critically Ill Patients after Cardiac Surgery

Table 2

Physiological, laboratory, and treatment variables at the start of clonidine or dexmedetomidine therapy.

Variable	All (n = 334)	Clonidine group (n = 193)	Dexmedetomidine group (n = 141)	value
Hemodynamic parameters
(i) Heart rate (1/min)	90 (80–100)	90 (75–100)	90 (80–105)	0.028
(ii) Mean arterial pressure (mmHg)	70 (65–75) n = 333	70 (65–80) n = 192	70 (65–75)	0.093
(iii) Central venous pressure (mmHg)	10 (7–12) n = 322	9 (6–12) n = 185	10 (8–13) n = 137	0.025
(iv) Cardiac index (l/m [2]/min)	2.7 (2.5–3.3) n = 51	2.6 (2.4–3.0) n = 19	2.8 (2.6–3.5) n = 32	0.101
(v) SvO2 (%)	69 (63–75) n = 239	69 (64–75) n = 173	65 (59–75) n = 66	0.060
Laboratory values
(i) Haemoglobin (g/l)	91 (83–103) n = 331	94 (85–107)	88 (80–97) n = 138	0.002
(ii) White blood cell count (G/l)	11.5 (8.8–15.1) n = 331	11.8 (8.8–15.1) n = 191	11.1 (8.6–15.1) n = 140	0.498
(iii) C-reactive protein (mg/l)	62 (14–131) n = 326	53 (6–133) n = 185	69 (34–129)	0.100
(iv) Procalcitonin (mcg/l)	1.91 (0.52–6.25) n = 46	1.43 (0.31–4.10) n = 28	3.46 (1.10–17.07) n = 18	0.075
(v) Creatinine (mcmol/l)	99 (78–141)	94 (76–133)	110 (83–150)	0.005
(vi) Aspartate transaminase (U/l)	62 (39–119) n = 322	55 (35–107) n = 184	71 (44–133) n = 138	0.026
(vii) Alanine transaminase (U/l)	27 (17–58) n = 325	27 (16–58) n = 188	28 (17–63) n = 137	0.606
(viii) Creatine kinase (U/l)	474 (242–847) n = 329	484 (228–889) n = 188	468 (255–807) n = 141	0.919
(ix) Myoglobin (mcg/l)	371 (218–767) n = 325	378 (229–670) n = 186	368 (214–898) n = 139	0.640
(x) Troponin (mcg/l)	0.81 (0.35–1.69) n = 320	0.78 (0.30–1.54) n = 184	0.84 (0.43–1.97) n = 136	0.135
(xi) Arterial lactate (mmol/l)	1.5 (1.0–2.3) n = 330	1.4 (1.05–2.2)	1.5 (1.0–2.6) n = 137	0.650
(xii) Arterial base excess (mmol/l)	−1.1 (−3.0–0.3) n = 330	−1.2 (−2.7–0.3)	−1.0 (−3.3–0.4) n = 137	0.574
Treatments
Propofol n (%)	127 (38%)	70 (36%)	57 (40%)	0.494
Mechanical ventilation
(i) Invasive n (%)	235 (70%)	124 (64%)	111 (79%)	0.017
(ii) Noninvasive n (%)	7 (2.1 %)	5 (2.6%)	2 (1.4%)
Renal replacement therapy-n (%)	34 (10.2 %)	23 (12%)	11 (7.8%)	0.235
Norepinephrine n (%)	248 (74 %)	133 (69 %)	115 (82%)	0.011
Inotropes
(i) Milrinone n (%)	80 (24%)	35 (18%)	45 (32%)	0.004
(ii) Epinephrine n (%)	73 (22%)	33 (17%)	40 (28%)	0.016

SvO₂: central venous oxygen saturation. Variables were collected at start of clonidine or dexmedetomidine treatment.