Electrocardiographic Abnormalities in Patients with Hyperkalemia: A Retrospective Study in an Emergency Department in Colombia

Figures & data

Table 1 Demographic and Clinical Characteristics of the Study Population

Variables	Available Data	Overall, n: 494	Classification of Hyperkalemia
			Mild (n: 102)	Moderate (n: 122)	Severe (n: 270)
Age*	494	63 (48–73)	64.5 (53–74)	65 (52–75)	61 (45–72)
Age ≥60 years	494	318 (64.4%)	93 (91.2%)	78 (63.9%)	147 (54.4%)
Gender
Female	494	212 (42.9%)	48 (47.1%)	58 (47.5%)	106 (39.3%)
Male	494	282 (57.1%)	54 (52.9%)	64 (52.5%)	164 (60.7%)
Background
Hypertension	494	354 (71.7%)	70 (68.6%)	85 (69.7%)	199 (73.7%)
Chronic kidney disease	494	311 (63.0%)	47 (46.1%)	58 (47.5%)	206 (76.3%)
Diabetes	494	173 (35.0%)	37 (36.3%)	51 (41.8%)	85 (31.5%)
Cancer	494	76 (15.4%)	19 (18.6%)	21 (17.2%)	36 (13.3%)
Heart failure	494	62 (12.6%)	10 (9.8%)	13 (10.7%)	39 (14.4%)
Immunosuppression	494	61 (12.4%)	7 (6.9%)	19 (15.6%)	35 (13.0%)
Autoimmune disease	494	36 (7.3%)	3 (2.9%)	10 (8.2%)	23 (8.5%)
Chronic obstructive pulmonary disease	494	27 (5.5%)	6 (5.9%)	9 (7.4%)	12 (4.4%)
Arrhythmias	494	10 (2.0%)	1 (1.0%)	0	9 (3.3%)
Asthma	494	4 (0.8%)	2 (2.0%)	0	2 (0.7%)
Physiological variables
Systolic blood pressure *	494	130 (111–152)	130 (114–147)	132.5 (108–152)	130 (112–154)
Diastolic blood pressure*	494	73 (61–86)	72 (64–85)	72 (58–84)	74.5 (60–88)
Heart rate*	494	83.5 (70–98)	84 (70–98)	85 (70–99)	82 (71–98)
Respiratory rate*	494	18 (17–20)	18 (17–20)	18 (17–20)	18 (17–20)
Arterial saturation*	494	97 (95–98)	97 (95–98)	96 (94–98)	97 (95–99)
Temperature, (C°)*	494	36.2 (36–36.5)	36.2 (36–36.5)	36.1 (36–36.5)	36.2 (36–36.5)
Paraclinical
Creatinine *	443	3.56 (1.9–8.2)	2.6 (1.7–6.6)	2.77 (1.6–5.3)	4.38 (2.5–9.7)
BUN*	470	57.3 (40–78.5)	53 (36.4–68.5)	50.7 (35.3–77.6)	63.1 (42.7–81.6)
Na*	466	136 (133–139)	137 (134–141)	136.9 (132.8–139.9)	135.7 (133–138)
K*	494	6.6 (6.1–7.0)	5.7 (5.6–5.9)	6.2 (6.1–6.3)	6.9 (6.6–7.3)
Mg*	192	2.03 (1.8–2.4)	2.01 (1.6–2.4)	1.92 (1.7–2.2)	2.12 (1.82–2.5)
Ca*	204	8.8 (8.1–9.6)	8.7 (7.6–9.2)	9.2 (8.5–9.8)	8.71 (7.81–9.5)
Cl*	384	101.5 (96.2–107)	102.7 (98–107.2)	101.4 (95.2–106.6)	100.7 (96.2–107)
Glucose*	333	119 (94–158)	129 (90–157)	120.5 (94–170.5)	117 (95–157)
Symptoms related to Hyperkalemia	494	175 (35.4%)	26 (25.5%)	41 (33.6%)	108 (40%)
Weakness	494	105 (21.3%)	18 (17.6%)	20 (16.4%)	67 (24.8%)
Nausea/vomiting	494	51 (10.3%)	6 (5.9%)	11 (9.0%)	34 (12.6%)
Abdominal pain	494	42 (8.5%)	7 (6.9%)	6 (4.9%)	29 (10.7%)
Respiratory distress	494	48 (9.7%)	8 (7.8%)	14 (11.5%)	26 (9.6%)
Slow, weak, or irregular pulse	494	17 (3.4%)	0	5 (4.1%)	12 (4.4%)
Anxiety	494	16 (3.3%)	0	6 (4.9%)	10 (3.7%)
Irritability and restlessness	494	15 (3.0%)	0	3 (2.5%)	12 (4.4%)
Numbness and tingling of the fingertips	494	12 (2.4%)	1 (1%)	1 (0.8%)	10 (3.7%)
Flaccid quadriplegia	494	2 (0.4%)	0	1 (0.8%)	1 (0.3%)
Initial Rhythm
Sinus rhythm	494	416 (84.2%)	74 (72.6%)	106 (86.9%)	236 (87.4%)
Sinus tachycardia	494	34 (6.9%)	13 (12.8%)	6 (4.9%)	15 (5.6%)
Atrial fibrillation	494	16 (3.2%)	6 (5.9%)	3 (2.5%)	7 (2.6%)
Sinus bradycardia	494	12 (2.4%)	3 (2.9%)	3 (2.5%)	6 (2.2%)
Indeterminate rhythm	494	7 (1.4%)	3 (2.9%)	3 (2.5%)	1 (0.4%)
AESP	494	3 (0.6%)	1 (1%)	0	2 (0.7%)
Atrial flutter	494	2 (0.4%)	1 (1%)	1 (0.8%)	0
Idioventricular rhythm	494	1 (0.2%)	0	0	1 (0.4%)
Ventricular tachycardia	494	1 (0.2%)	1 (1%)	0	0
Asystole	494	1 (0.2%)	0	0	1 (0.4%)
Pulseless ventricular tachycardia	494	1 (0.2%)	0	0	1 (0.4%)
Treatment
Insulin / Glucose	494	281 (56.9%)	44 (43.1%)	69 (56.6%)	168 (62.2%)
Loop Diuretics	494	263 (53.2%)	53 (52%)	69 (56.6%)	141 (52.2%)
Beta agonist	494	231 (46.8%)	36 (35.3%)	58 (47.5%)	137 (50.7%)
Calcium salts	494	209 (42.3%)	22 (21.6%)	50 (41%)	137 (50.7%)
Hemodialysis	494	199 (40.3%)	32 (31.4%)	40 (32.8%)	127 (47%)
Ion exchange resins	494	191 (38.7%)	28 (27.4%)	47 (38.5%)	116 (43%)
Sodium bicarbonate	494	144 (29.25)	33 (32.4%)	26 (21.3%)	85 (31.5%)
No treatment	494	9 (1.8%)	3 (2.9%)	3 (2.5%)	3 (1.1%)
Principal diagnostic
Renal diseases	494	172 (34.8%	22 (21.6%)	35 (28.7%)	115 (42.59%)
Infectious diseases	494	86 (17.4%)	21 (20.6%)	18 (14.8%)	47 (17.4%)
Cardiovascular diseases	494	57 (11.5%)	16 (15.7%)	21 (17.2%)	20 (7.4%)
Postoperative	494	47 (9.5%)	14 (13.7%)	14 (11.5%)	19 (7%)
Metabolic diseases	494	37 (7.5%)	4 (3.9%)	10 (8.2%)	23 (8.5%)
Neoplasia	494	32 (6.5%)	7 (6.9%)	9 (7.4%)	16 (5.9%)
Digestive diseases	494	22 (4.4%)	4 (3.9%)	7 (5.7%)	11 (4.1%)
Respiratory diseases	494	12 (2.4%)	3 (2.9%)	3 (2.5%)	56 (2.2%)
Neurological diseases	494	11 (2.2%)	7 (6.9%)	3 (2.5%)	1 (0.4%)
Trauma	494	6 (1.2%)	1 (1%)	1 (0.8%)	4 (1.5%)
Immuno-Rheumatology diseases	494	5 (1.0%)	1 (1%)	1 (0.8%)	3 (1.1%)
Hematological diseases	494	2 (0.4%)	1 (1%)	0	1 (0.4%)
Neuromuscular diseases	494	2 (0.4%)	0	0	2 (0.7%)
Toxicity	494	1 (0.4%)	1 (1%)	0	1 (0.4%)
Urological diseases	494	1 (0.4%)	0	0	1 (0.4%)
Vascular diseases	494	1 (0.4%)	0	0	1 (0.4%)
Abnormal ECG findings	494	304 (61.5%)	57 (55.9%)	78 (63.9%)	169 (62.6%)
Hospitalization days**	494	15.33 (± 20.61)	17.5 (± 26.19)	14.2 (± 18.1)	14.9 (±19.26)
Intra-hospital death	494	59 (11.9%)	16 (15.7%)	14 (11.5%)	29 (10.7%)

Notes: *Median (IQR), **Mean (SD).

Figure 1 Flowchart.

Figure 2 ECG findings and degrees of hyperkalemia.

Table 2 Relationship Between Abnormal Electrocardiogram Findings/Demographic Variables and Severity of Hyperkalemia

Variables	Mild, n: 102	Moderate, n: 122	Severe, n: 270	P -value
Age ≥ 60
No	9 (8.8%)	44 (36.1%)	123 (45.6%)	<0.001
Yes	93 (91.2%)	78 (63.9%)	147 (54.4%)
Gender
Female	48 (47.1%)	58 (47.5%)	106 (39.3%)	0.197
Male	54 (52.9%)	64 (52.5%)	164 (60.7%)
Cardiac arrest rhythms
No	101 (99.0%)	122 (100%)	266 (98.5%)	0.253
Yes	1 (1.0%)	0	4 (1.5%)
Renal chronic disease
No	55 (53.9%)	64 (52.5%)	64 (23.7%)	< 0.001
Yes	47 (46.1%)	58 (47.5%)	206 (76.3%)
Diabetes
No	65 (63.7%)	71 (58.2%)	185 (68,5%)	0.134
Yes	37 (36.3%)	51 (41.8%)	85 (31,5%)
Abnormal electrocardiogram findings
No	45 (44,1%)	44 (36.1%)	101 (37.4%)	0.406
Yes	57 (55.9%)	78 (63.9%)	169 (62.6%)
Peaked t wave
No	80 (78.4%)	71 (58.2%)	164 (60.7%)	0.002
Yes	22 (21.6%)	51 (41.8%)	106 (39.3%)
Wide QRS with bizarre morphologies
No	88 (86.3%)	101 (82.8%)	222 (82.8%)	0.641
Yes	14 (13.7%)	21 (17.2%)	48 (17.2%)
Prolonged PR interval
No	91 (89.2%)	105 (86.1%)	231 (85.6%)	0.649
Yes	11 (10.8%)	17 (13.9%)	39 (14.4%)
Heart block
No	85 (83.3%)	105 (86.1%)	239 (88.5%)	0.401
Yes	17 (16.7%)	17 (13.9%)	31 (11.5%)
Widening and flattening of the P wave
No	92 (90.2%)	109 (89.3%)	241 (89.3%)	0.965
Yes	10 (9.8%)	13 (10.7%)	29 (10.7%)
Disappearance of the P wave
No	94 (92.2%)	116 (95.1%)	253 (93.7%)	0.667
Yes	8 (7.8%)	6 (4.9%)	17 (6.3%)
Sinusoidal wave
No	102 (100%)	122 (100%)	266 (98.5%)	0.188
Yes	0	0	4 (1.5%)

Table 3 Relationship Between Abnormal Electrocardiogram Findings and Severity of Hyperkalemia in Patients with CKD

Variables	Mild, n: 47	Moderate, n: 58	Severe, n: 206	P-value
Age ≥ 60
No	3 (6,4%)	22 (37.9)	99 (48.1%)	<0.001
Yes	44 (93.6%)	36 (62.1)	107 (51.9%)
Gender
Female	20 (42.6%)	25 (43.1%)	78 (37.9%)	0.197
Male	27 (57.4%)	33 (56.1%)	128 (62.1%)
Abnormal Electrocardiogram Findings
No	18 (38.3%)	22 (37.9%)	76 (36.9%)	0.978
Yes	29 (61.7%)	36 (62.1%)	130 (63.1%)
Peaked t wave
No	34 (72.3%)	35 (60.3%)	124 (60.2%)	0.288
Yes	13 (27.7%)	23 (39.7%)	82 (39.8%)
Wide QRS with bizarre morphologies
No	39 (83%)	47 (81%)	167 (81.1%)	0.953
Yes	8 (17%)	11 (19%)	39 (18.9%)
Prolonged PR interval
No	41 (87.2%)	54 (93.1%)	176 (85.4%)	0.305
Yes	6 (12.8%)	4 (6.9%)	30 (14.6%)
Heart block
No	40 (85.1%)	51 (87.9%)	182 (88.3%)	0.828
Yes	7 (14.9%)	7 (12.1%)	24 (11.7%)
Widening and flattening of the P wave
No	41 (87.2%)	51 (87.9%)	182 (88.3%)	0.977
Yes	6 (12.8%)	7 (12.1%)	24 (11.7%)
Disappearance of the P wave
No	41 (87.2%)	54 (93.1%)	194 (94.2%)	0.246
Yes	6 (12.8%)	4 (6.9%)	12 (5.8%)
Cardiac arrest rhythms
No	47 (100%)	58 (100%)	203 (98.5%)	0.462
Yes	0	0	3 (1.5%)
Sinusoidal wave
No	47 (100%)	58 (100%)	202 (98.1%)	0.356
Yes	0	0	4 (1.9%)

Table 4 Multivariate Analysis

Variable	Odds Ratio	p value	CI (95%)
Age ≥60	0.123	>0.001	0.588–0.259
Sex	1.517	0.092	0.934–2.464
Diabetes	1.344	0.242	0.818–2.206
Chronic kidney disease	2.082	0.002	1.3–3.335
Peaked t wave	2.355	>0.001	1.36–4,078

Figure 3 Treatment.

Table 5 Description of Deceased Patients

	Mild (n: 16)	Moderate (n: 14)	Severe (n: 29)
Age by groups
< 60	1 (6.2%)	4 (28.6%)	6 (20.7%)
≥ 60	15 (93.8%)	10 (71.4%)	23 (79.3%)
Principal diagnostic
Cardiovascular diseases	3 (18.8%)	7 (50%)	4 (13.8%)
Digestive diseases	0	0	1 (3.4%)
Infectious diseases	9 (56.3%)	6 (42.9%)	10 (34.5%)
Metabolic diseases	0	0	1 (3.4%)
Neoplasia	1 (6.2%)	0	3 (10.3%)
Neurological diseases	0	0	1 (3.4%)
Trauma	0	0	1 (3.4%)
Renal diseases	2 (12.5%)	1 (7.1%)	7 (24.1%)
Respiratory diseases	1 (6.2%)	0	1 (3.4%)
Initial rhythm
AESP	1 (6.2%)	0	1 (3.4%)
Sinus bradycardia	1 (6.2%)	0	1 (3.4%)
Atrial fibrillation	4 (25%)	1 (7.1%)	0
Indeterminate rhythm	1 (6.2%)	0	0
Sinus rhythm	7 (43.8%)	12 (85.7%)	26 (89.7%)
Sinus tachycardia	2 (12.5%)	1 (7.1%)	1 (3.4%)
Abnormal ECG findings	12 (75%)	8 (57.1%)	21 (72.4%)