Prevalence of Bradycardia After Induction of General Anesthesia and Associated Factors Among Surgical Pediatric Patients. A Prospective Observational Study

Figures & data

Figure 1 Flow chart summarizing the study design and procedures of the study conducted on the prevalence of bradycardia and its associated factors after induction of general anesthesia among pediatric patients operated at Hawassa University Comprehensive Specialized Hospital.

Table 1 Socio-demographic Characteristics of Pediatric Patients Operated at Hawassa University Comprehensive Specialized Hospital, Ethiopia (n=205)

Variables	Categories	Frequency (%)	Bradycardia After General Anesthesia, Frequency (%)
			Yes (n=40)	No (n=165)
			40 (19.5)	165 (80.5)
Sex	Male	117 (57.1)	26 (22.2)	91 (77.8)
	Female	88 (42.9)	14 (15.9)	74 (84.1)
Age		1.20±4.72	1.91±1.78	2.92±5.29
Weight (kg)		15.30±7.47	11.12±7.26	16.3±7.18

Figure 2 Prevalence of bradycardia after induction of general anesthesia among pediatric patients operated at Hawassa University Comprehensive Specialized Hospital.

Table 2 A Cross-Tabulation of the Preoperative Factors Among Pediatric Patients Operated at Hawassa University Comprehensive Specialized Hospital, Ethiopia (n=205)

Variables		Categories		Frequency (%)	Bradycardia After General Anesthesia, Frequency (%)
					Yes (n=40)	No (n=165)
					40 (19.5)	165 (80.5)
ASA class		ASA-1		134 (65.4)	16 (11.9)	118 (88.1)
		ASA-2		71 (34.6)	24 (33.8)	47 (66.2)
Premedication		Anticholinergics	Yes	60 (29.3)	16 (26.7)	44 (73.3)
			No	145 (70.7)	24 (16.6)	121 (83.4)
		Opioids	Yes	39 (19)	27 (69.2)	12 (30.8)
			No	166 (81)	23 (13.9)	143 (86.1)
		Others (steroids, diazepam)	Yes	27 (13.2)	8 (29.6)	19 (70.4)
			No	178 (86.8)	32 (18)	146 (82)
Preoperative hemoglobin levels (g/dL)				12.24±5.23	7.05±1.40	12.64±1.74
Preoperative risk of hypoxia (decreased levels of arterial oxygen saturation)			Yes	79 (38.5)	28 (35.4)	51 (64.6)
			No	126 (61.5)	12 (9.5)	114 (90.5)
Nature surgery		Emergency		63 (30.7)	20 (31.7)	43 (68.5)
		Elective		142 (69.3)	20 (14.1)	122 (85.9)

Table 3 A Cross-Tabulation of the Intraoperative Factors Among Pediatric Patients Operated at Hawassa University Comprehensive Specialized Hospital, Ethiopia (n=205)

Variables	Categories		Frequency (%)	Bradycardia After General Anesthesia, Frequency (%)
				Yes (n=40)	No (n=165)
				40 (19.5)	165 (80.5)
Vital signs	Blood pressure (mmHg)		84.12±22.88 / 45.13±12.72	65±33 / 29.50±17.11	91±23 / 51.02±9.91
	Heart rate (beats per minute)		113±43	113±43	109±41
	Oxygen saturation (%)		96.1±3.90	89.23±9.08	97.03±2.51
	Temperature (°C)		36.22±1.31	35.43±1.01	36.05±0.09
Induction of general anesthesia	IV induction	Yes	157 (76.6)	14 (8.9)	143 (91.1)
		No	48 (23.4)	26 (54.2)	22 (45.8)
	Inhalational induction	Yes	35 (17.1)	14 (40)	21 (60)
		No	170 (82.9)	26 (15.3)	144 (84.7)
Induction agent	Ketamine	Yes	62 (30.2)	12 (19.4)	50 (80.6)
		No	143 (69.8)	28 (19.6)	115 (80.4)
	Propofol	Yes	73 (35.6)	16 (21.9)	57 (78.1)
		No	132 (64.4)	24 (18.2)	108 (81.8)
	Ketofol	Yes	54 (26.3)	6 (11.1)	48 (88.9)
		No	151 (73.7)	34 (22.5)	117 (77.5)
	Halothane	Yes	10 (4.9)	6 (60)	4 (40)
		No	195 (95.1)	34 (17.4)	161 (82.6)
Airway management	Face mask	Yes	46 (22.4)	6 (13)	40 (87)
		No	159 (77.6)	34 (21.4)	125 (78.6)
	LMA	Yes	22 (10.7)	4 (18.2)	18 (81.8)
		No	183 (89.3)	36 (19.7)	147 (80.3)
	ETT	Yes	129 (62.9)	11 (8.5)	118 (91.5)
		No	76 (37.1)	29 (38.2)	47 (61.8)
Difficult intubation		Yes	34 (16.6)	27 (79.4)	7 (20.6)
		No	171 (83.4)	13 (7.6)	158 (92.4)
Maintenance of anesthesia		Isoflurane	65 (31.7)	11 (16.9)	54 (83.1)
		Halothane	88 (42.9)	19 (21.6)	69 (78.4)
		Propofol	831 (15.1)	8 (38.1)	13 (61.9)
		Others (ketofol, ketamine)	21 (10)	2 (6.5)	29 (93.5)
Types of surgery		Ophthalmological	73 (35.6)	9 (12.3)	64 (87.7)
		General surgery	59 (28.8)	13 (22)	46 (78)
		Neurosurgery	31 (15.1)	7 (22.6)	24 (77.4)
		Urology	24 (11.7)	5 (20.8)	19 (79.2)
		ENT	11 (5.4)	4 (36.4)	7 (63.6)
		Others (ortho, plastic, OMFS)	7 (3.4)	2 (28.6)	5 (71.4)
Muscle relaxant used during maintenance		Succinylcholine	21 (20)	14 (66.7)	7 (33.3)
		Vecuronium	84 (80)	28 (33.3)	56 (66.7)
Intraoperative complications		Yes	57 (27.8)	16 (28.1)	4 1 (71.9)
		No	148 (72.2)	24 (16.2)	124 (83.8)
Complications		No	148 (72.2)	24 (16.2)	124 (83.8)
		Hypoxia	21 (10.2)	5 (23.8)	16 (76.2)
		Significant blood loss	9 (4.4)	2 (22.2)	7 (77.8)
		Hypothermia	11 (5.4)	2 (18.2)	9 (81.8)
		Hypoglycemia	8 (3.9)	3 (37.5)	5 (62.5)
		Others (fluid load)	8 (3.9)	4 (50)	4 (50)

Figure 3 The frequency of types of surgery conducted and its respective prevalence of bradycardia after induction of general anesthesia among pediatric patients operated at Hawassa University Comprehensive Specialized Hospital.

Table 4 Results of Bivariable Logistic Regression of Factors Associated with Bradycardia After Induction of General Anesthesia Among Pediatric Patients Operated at Hawassa University Comprehensive Specialized Hospital, Ethiopia (n=205)

Variables	Categories			Bradycardia After General Anesthesia, Frequency (%)		COR (95% CI)	P-value
				Yes (n=40)	No (n=165)
				40 (19.5)	165 (80.5)
ASA class	ASA-I			16 (11.9)	118 (88.1)	1
	ASA-II			24 (33.8)	47 (66.2)	0.27 (0.13–0.54)	0.14
Preoperative risk of hypoxia (desaturation)			No	12 (9.5)	114 (90.5)	1
			Yes	28 (35.4)	51 (64.6)	5.22 (2.45–11.0)	0.12
Premedications	Anticholinergics		Yes	16 (26.7)	44 (73.3)	1
			No	24 (16.6)	121 (83.4)	1.83 (0.89–3.77)	0.21
	Opioids		No	13 (13.9)	143 (86.1)	1
			Yes	27 (69.2)	12 (30.8)	26.5 (10.9–64.2)	0.24
	Others (steroids, diazepam)		No	32 (18)	146 (82)	1
			Yes	8 (29.6)	19 (70.4)	1.92 (0.21–1.29)	0.26
Nature of surgery	Elective			20 (14.1)	122 (85.9)	1
	Emergency			20 (31.7)	43 (68.5)	0.35 (0.17–0.72)	0.28
Induction of general anesthesia	IV induction		Yes	14 (8.9)	143 (91.1)	1
			No	26 (54.2)	22 (45.8)	0.08 (0.04–0.18)	0.22
	Inhalational induction		No	26 (15.3)	144 (84.7)	1
			Yes	14 (40)	21 (60)	3.69 (1.67–8.17)	0.10
Induction agent	Ketamine		Yes	12 (19.4)	50 (80.6)	1
			No	28 (19.6)	115 (80.4)	0.98 (0.46–2.10)	0.36
	Propofol		No	24 (18.2)	108 (81.8)	1
			Yes	16 (21.9)	57 (78.1)	1.26 (0.39–1.61)	0.52
	Ketofol		Yes	6 (11.1)	48 (88.9)	1
			No	34 (22.5)	117 (77.5)	0.43 (0.17–1.09)	0.30
	Halothane		No	34 (17.4)	161 (82.6)	1
			Yes	6 (60)	4 (40)	7.10 (1.90–26.5)	0.08
Airway management	Face mask		No	34 (21.4)	125 (78.6)	1
			Yes	6 (13)	40 (87)	0.55 (0.22–1.41)	0.21
	LMA		Yes	4 (18.2)	18 (81.8)	1
			No	36 (19.7)	147 (80.3)	0.91 (0.29–2.85)	0.86
	ETT		No	29 (38.2)	47 (61.8)	1
			Yes	11 (8.5)	118 (91.5)	0.15 (0.07–0.34)	0.18
Difficult intubation			No	13 (7.6)	158 (92.4)	1
			Yes	27 (79.4)	7 (20.6)	46.8 (17.2–51.4)	0.02
Maintenance of anesthesia	Isoflurane			11 (16.9)	54 (83.1)	1
	Halothane			19 (21.6)	69 (78.4)	1.35 (0.59–3.08)	0.06
	Propofol			8 (38.1)	13 (61.9)	3.02 (0.87–18.3)	0.07
	Others (ketofol, ketamine)			2 (6.5)	29 (93.5)	0.34 (0.16–1.24)	0.12
Muscle relaxants used	Succinylcholine			14 (66.7)	7 (33.3)	0.25 (0.36–1.15)	0.28
	Vecuronium			28 (33.3)	56 (66.7)	1
Types of surgery	Others (ortho, plastic, OMFS)			2 (28.6)	5 (71.4)	1
	ENT			4 (36.4)	7 (63.6)	1.43 (0.25–8.16)	0.19
	Urology			5 (20.8)	19 (79.2)	0.66 (0.48–16.9)	0.25
	Neurosurgery			7 (22.6)	24 (77.4)	0.73 (0.22–10.3)	0.17
	General surgery			13 (22)	46 (78)	0.71 (0.09–5.43)	0.23
	Ophthalmological			9 (12.3)	64 (87.7)	0.35 (0.22–8.66)	0.34
Intraoperative complications	No			24 (16.2)	124 (83.8)	1
	Yes			16 (28.1)	41 (71.9)	2.02 (0.24–1.02)	0.16
Complications	No			24 (16.2)	124 (83.8)	1
	Hypoxia			5 (23.8)	16 (76.2)	1.61 (0.17–7.06)	0.15
	Blood loss			2 (22.2)	7 (77.8)	1.47 (0.23–8.78)	0.16
	Hypothermia			2 (18.2)	9 (81.8)	1.15 (1.9–2.90)	0.46
	Hypoglycemia			3 (37.5)	5 (62.5)	3.10 (0.60–1.73)	0.22
	Others (fluid load)			4 (50)	4 (50)	5.17 (1.54–4.83)	0.39

Notes: Bold p-value = Significant association on bivariable logistic regression at p-value <0.25. 1- Reference group.

Table 5 Results of Multivariable Logistic Regression of Factors Independently Associated with Bradycardia After Induction of General Anesthesia Among Pediatric Patients Operated at Hawassa University Comprehensive Specialized Hospital, Ethiopia (n=205)

Variables	Categories		AOR (95% CI)	P-value
ASA class	ASA-I		1
	ASA-II		1.95 (8.20–24.74)	0.08
Risk of hypoxia (desaturation)		No	1
		Yes	1.33 (0.12–1.46)	0.04
Premedications	Anticholinergics	Yes	1
		No	0.59 (0.04–8.44)	0.20
	Opioids	No	1
		Yes	2.40 (0.03–0.22)	0.01
Induction of general anesthesia	IV induction	Yes	1
		No	1.03 (3.15–13.9)	0.21
	Inhalational induction	No	1
		Yes	10.5 (2.80–39.7)	0.02
Induction agent	Halothane	No	1
		Yes	1.50 (1.22–14.5)	0.04
Airway management	Face mask	No	1
		Yes	19.5 (0.49–7.75)	0.11
	ETT	No	1
		Yes	1.38 (3.56–5.41)	0.12
Difficult intubation		No	1
		Yes	2.35 (0.46–0.88)	0.001
Maintenance of anesthesia	Isoflurane		1
	Halothane		0.13 (0.04–8.44)	0.43
	Propofol		0.71 (0.08–24.83)	0.89
	Others (ketofol, ketamine)		0.70 (0.00–2.0)	0.38
Types of surgery	Others (ortho, plastic, OMFS)		1	0.53
	ENT		0.23 (0.01–0.27)	0.43
	Urology		0.61 (1.11–80)	0.37
	Neurosurgery		0.30 (10.0–22.2)	0.26
	General surgery		0.40 (1.02–5.22)	0.25
Intraoperative complications	No		1
	Yes		1.65 (0.04–0.77)	0.02
Complications	No		1	0.09
	Hypoxia		6.5 (5.22–45.12)	0.03
	Significant blood loss		14.6 (1.75–5.76)	0.04
	Hypoglycemia		0.24 (4.14–11.9)	0.73

Notes: Bold: Significant association on multivariable logistic regression.