Vol. 37 No.2. May-August 2019 • ISSNe: 2216-0280
Original article
Metabolic fatigue 
in resuscitators using 
personal protection 
equipment against 
biological hazard
Francisco Martín-Rodríguez1,2
1  M.Sc, Ph.D. Professor, Centro de Simulación Clínica 
Avanzada. Facultad de Medicina. Universidad de 
Valladolid. 
2  Unidad Móvil de Emergencias Valladolid I, Gerencia 
de Emergencias Sanitarias de Castilla y León 
(SACYL). España.
 
Email: fmartin@saludcastillayleon.es
Conflicts of interest: none.
Received: October 8th, 2018.
Approvedptado: June 4th, 2019.
How to cite this article: Martín-Rodríguez F. Metabolic 
fatigue in resuscitators using personal protection equip-
ment against biological hazard. Invest. Educ. Enferm. 
2019; 37(2):e04.
DOI: 10.17533/udea.iee.v37n2e04
Metabolic fatigue in resuscitators using 
personal protection equipment against 
biological hazard
Abstract
Objective. To describe the effects of wearing individual 
protection equipment against biological hazard when 
performing 
a 
simulated 
resuscitation. 
Methods. 
Uncontrolled quasi-experimental study involving 47 
volunteers chosen by random sampling stratified by sex 
and professional category. We determined vital signs, 
anthropometric parameters and baseline lactate levels; 
subsequently, the volunteers put on level D individual 
protection equipment against biological hazard and 
performed a simulated resuscitation for 20 minutes. After 
undressing and 10 minutes of rest, blood was extracted 
again to determine lactate levels. Metabolic fatigue was 
defined as a level of lactic acid above 4 mmol/L at the 
end of the intervention. Results. 25.5% of the participants 
finished the simulation with an unfavorable metabolic 
tolerance pattern. The variables that predict metabolic 
Metabolic fatigue in resuscitators using personal protection equipment against biological hazard
Invest Educ Enferm. 2019; 37(2): e04
fatigue were the level of physical activity and bone mass -in a protective form- 
and muscle mass. People with a low level of physical activity had ten times the 
probability of metabolic fatigue compared to those with higher levels of activity 
(44% versus 4.5%, respectively). Conclusion. Professionals who present a medium 
or high level of physical activity tolerate resuscitation tasks better with a level D 
individual biological protection suit in a simulated resuscitation.
Descriptors: cardiopulmonary resuscitation; personal protective equipment; 
anaerobic threshold; containment of biohazards; stress, physiological.
Fatiga metabólica en reanimadores usando equipos de 
protección personal frente a riesgos biológicos
Resumen
Objetivo. Describir cómo afecta llevar puesto un equipo de protección individual 
frente a riesgos biológicos durante la realización de una reanimación simulada. 
Métodos. Estudio cuasi-experimental no controlado en el que participaron 47 
voluntarios elegidos mediante un muestreo aleatorio estratificado por sexo y categoría 
profesional. Se realizó una toma de contantes vitales y parámetros antropométricos, 
así como una determinación basal de lactato; posteriormente, los voluntarios se 
pusieron un equipo de protección individual nivel D frente a riesgos biológicos y 
realizaron una reanimación simulada durante 20 minutos; después del desvestido 
y de 10 minutos de reposo se realizó otra extracción de sangre para conocer los 
niveles de lactato. Se definió fatiga metabólica si el nivel de ácido láctico al final 
de la intervención estaba por encima de 4 mmol/L. Resultados El 25.5% de los 
participantes terminó la simulación con un mal patrón de tolerancia metabólica. Las 
variables que predicen la fatiga metabólica son el nivel de actividad física y la masa 
ósea –en forma protectora- y la masa muscular. Las personas con un nivel bajo de 
actividad física tuvieron diez veces la probabilidad de fatiga metabólica comparadas 
con las de niveles más altos de actividad (44% versus 4.5%, respectivamente). 
Conclusión. Los profesionales que presentan un nivel de actividad física media o 
alta toleran mejor las labores de reanimación con un traje de protección biológica 
individual nivel D, en el caso de reanimación simulada.
Francisco Martín-Rodríguez
Invest Educ Enferm. 2019; 37(2): e04
Descriptores: reanimación cardiopulmonar; equipo de protección personal; umbral 
anaerobio; contención de riesgos biológicos; estrés fisiológico.
Fatiga metabólica em reanimadores usando 
equipamentos de proteção pessoal frente a riscos 
biológicos
Resumo
Objetivo. Descrever como afeta vestir um equipamento de proteção individual frente 
a riscos biológicos durante a realização de uma reanimação simulada. Métodos. 
Estudo quase-experimental não controlado no qual participaram 47 voluntários 
elegidos mediante uma amostragem aleatória estratificado por sexo e categoria 
profissional. Se realizou uma toma de concreta e de parâmetros antropométricos, 
assim como uma determinação basal de lactato; posteriormente, os voluntários 
vestiram um equipamento de proteção individual nível D frente a riscos biológicos 
e realizaram uma reanimação simulada durante 20 minutos; depois do desvestido 
e de 10 minutos de repouso se realizou outra extração de sangue para conhecer os 
níveis de lactato. Se definiu fatiga metabólica se o nível de ácido láctico ao final da 
intervenção estava por encima de 4 mmol/L. Resultados 25.5% dos participantes 
terminou a simulação com um mal padrão de tolerância metabólica. As variáveis 
que predizem a fatiga metabólica são o nível de atividade física e a massa óssea –em 
forma protetora- e a massa muscular. As pessoas com um nível baixo de atividade 
física tiveram dez vezes a probabilidade de fatiga metabólica comparadas com as 
de níveis mais altos de atividade (44% versus 4.5%, respectivamente). Conclusão. 
Os profissionais que apresentam um nível de atividade física média ou alta toleram 
melhor os trabalhos de reanimação com um equipamento de proteção biológica 
individual nível D, no caso de reanimação simulada.
Descritores: reanimação cardiopulmonar; equipamento de proteção individual; 
limiar anaeróbio; contenção de riscos biológicos; estresse fisiológico.
Invest Educ Enferm. 2019; 37(2): e04
Metabolic fatigue in resuscitators using personal protection equipment against biological hazard
Introduction 
I
n “conventional” resuscitation, health personnel must perform 
cardiopulmonary resuscitation techniques according to protocol.(1) 
However, the consequences of a cardiorespiratory arrest occurring in 
highly complex situations, such as an incident with biological hazard, are 
not known. The risk to health personnel necessarily implies the use of personal 
protective equipment (PPE). The recent Ebola virus epidemic in West Africa(2) 
has confronted health systems around the world with an alarming reality of 
biological hazard situations. It is increasingly common to attend numerous 
incidents - either provoked or unanticipated - that generate situations of 
collective emergency in which certain substances with biological hazard are 
implicated. These are situations that require a highly specialized response; 
in short: situations that must be handled comprehensively by the Emergency 
Services. The usual work of emergency teams is per se difficult, changing and 
often unfolding before a complex background. Professionals placed in such 
scenarios with diverse requirements must have received special attitudes and 
skills from education and training and in providing materials and resources.
The risk of a situation with biological hazard occurring is percentually low 
compared with other types of disasters,(3) but, due to its multiple and varied 
repercussions, the system must be specially prepared and trained. The various 
PPEs must represent the backbone of protective systems, the prevention of 
contagion and, by definition, the control of the situation. This type of incidents, 
despite currently being isolated cases, occur with certain frequency,(4) so we 
must be prepared to intervene in these scenarios. Most are caused either by 
accidental situations, or because appropriate safety measures for the handling 
or transport of certain substances have not been taken.(4) To these accidents 
we must add the possibility of terrorist acts; a situation that, unfortunately, 
is happening more frequently, as has been demonstrated in several attempts 
frustrated by the police worldwide in recent years.(5)
The use of PPE has improved both the assistance to victims and the survival 
of those involved in chemical or biological incidents, but this type of protection 
could otherwise reduce a person’s operational capacity. When selecting 
protective equipment for biological and chemical preparation, a balance must 
be struck between the degree of protection necessary for the potential hazard in 
question and the resulting difficulty in carrying out user functions.(6)  Performing 
their work in situations of biological hazard with the necessary level of protection 
directly affects the physiology of health workers, since it generates significant 
metabolic fatigue. This metabolic fatigue can increase the risk of accidents 
with PPE, increase cross-contamination, and lead to hasty termination of the 
procedures due to physiological stress, among others. Emergency services 
should contemplate these situations when planning interventions.(7) 
Therefore, the question arises: Are all workers in the emergency services 
able to tolerate physiologically performing a resuscitation with PPE in the 
face of biological hazard? To answer this question, we selected a level of 
Invest Educ Enferm. 2019; 37(2): e04
Francisco Martín-Rodríguez
lactic acid above 4 mmol/L at the end of the 
intervention as the parameter for the appearance 
of metabolic fatigue.(8)  The objective of this study 
was to describe the effects of wearing individual 
protection equipment against biohazard when 
performing a simulated resuscitation.
Methods
Type of study and sample. An uncontrolled quasi-
experimental study was performed in 2016 
including 47 volunteers chosen through random 
sampling stratified by sex and professional 
category (doctors and nurses of the Hospital 
Emergency Services and Prehospital Emergencies) 
of an opportunity sample of 104 volunteers. 
We included professionals from the hospital 
emergency services of the University Clinic and 
Río Hortega University Hospital in Valladolid 
and professionals of the prehospital emergencies 
system of Castilla y León (mobile emergency 
units of: Palencia, Salamanca and Valladolid, 
both urban and rural) in Spain. We included 
voluntary participants between 22 and 65 years. 
Any volunteer who presented at least one of the 
following exclusion criteria was rejected: severe 
motor, visual or hearing impairment, acute phase 
skin disease, body mass index greater than 40 kg/
m2, systolic blood pressure below 80 mmHg and 
baseline heart rate above 150 bpm.
Environmental conditions and personal protective 
equipment used. All participants performed 
the same simulated clinical case, in the same 
diaphanous laboratory room of 20 m2, with an 
average controlled temperature of 33.6±4.3ºC 
and an average controlled humidity of 51.1 ± 
1.5%. All PPE elements used in the performance 
of the practice case conformed with European 
Community standards and had an instruction 
manual. Elements are listed in the order of 
placement: boot covers, protective overall, inner 
nitrile gloves, hood, FFP3 mask, panoramic and 
self-ventilated protective goggles and outer nitrile 
gloves.
Photo 1. Enactment of the emergency services with biological 
protection suits (Photo by Francisco Martín-Rodríguez)
Invest Educ Enferm. 2019; 37(2): e04
Metabolic fatigue in resuscitators using personal protection equipment against biological hazard
Variables studied and measurement equipment. 
An anthropometric study was conducted to 
assess the following parameters: height, weight, 
body fat, muscle mass, bone mass, body mass 
index and total water content. For measuring 
the volunteers, we used a SECA® model 206 
mechanical metric tape and for measuring weight 
and bio-impedance, we used a Tanita® precision 
scale model BC-601. The volunteers were asked 
to sit in a chair, roll up their sleeves and wait 5 
minutes calmly, to have their vital signs taken: 
heart rate, systolic and diastolic blood pressure, 
respiratory rate, tympanic temperature, total 
hemoglobin, perfusion index, oxygen saturation 
and basal glycaemia. For determining systolic 
blood pressure, diastolic blood pressure and heart 
rate, we used a SCHILLER brand BP-200 plus 
meter. The temperature was measured with a 
tympanic brand BRAUN model ThermoScan PRO 
6000 thermometer with ExacTemp technology. 
The values  of total hemoglobin, oxygen saturation 
and perfusion index were obtained with a MASIMO 
model Pronto 7 multiparameter monitor, with 
software version b99e80000004ef796 (2.2.15), 
and revision version of sensor a83f90f0000c53f2, 
and glucose levels in blood with an Accu-Chek 
Mobile meter from Roche®. For determining lactic 
acid levels, we used an Accutrend® Plus meter 
from Roche® with a measuring range of 0.8-
21.7 mmol/L, with three measurements: baseline 
determination, just after the volunteer perform 
the cardiac massage and once the case was 
concluded after 10 minutes of rest. In addition, 
each volunteer completed the IPAQ physical 
activity questionnaire.(9)  The test has seven items 
with high reliability (α = 0.80), suitable for 
people aged 15 and above. The full version of the 
questionnaire can be found on the website: www.
ipaq.ki.se. The unit of measurement is called METs 
(unit of measurement of the metabolic index), and 
corresponds to the sum of the following activities: 
walking, moderate physical activity and vigorous 
physical activity. Once the physical activity 
questionnaire is completed, the volunteers are 
classified into three levels based on the exercise 
performed in the last seven days, as follows:(10)  
high level: vigorous physical activity at least 3 
days per week achieving a total of at least 1500 
METs, or 7 days of any combination of walking, 
with moderate physical activity and/or vigorous 
physical activity, achieving a total of at least 3000 
METs; moderate level: 3 or more days of vigorous 
physical activity for at least 20 minutes per day, 
or 5 or more days of moderate physical activity 
and/or walking at least 30 minutes per day, or 
5 or more days of any combination of walking, 
moderate or vigorous physical activity achieving a 
total of at least 600 METs; low or inactive level: 
not meeting any of the above criteria.
Development of the clinical simulation scenario. 
All participants in the study had the same 
information and the same materials and medical 
devices to solve the same case. The volunteers, 
guided by a biohazard specialist, had ten minutes 
to equip themselves completely, following by 
checking their suits. Once equipped with the PPE, 
they entered a room with controlled temperature 
and humidity and had to attend to a convulsing 
patient with possible biological hazard. After 
10 minutes of simulation, the patient suffered a 
cardiac arrest and the volunteers had to perform 
a regulated resuscitation during 20 minutes. The 
total duration of the case inside the laboratory 
was 30 minutes. Once the practical case 
was completed, the PPE was taken off under 
supervision, and 10 minutes after the removal of 
the PPE, vital signs were taken again.
Statistical analysis. The qualitative variables are 
summarized with their frequency distribution, 
and the quantitative variables in their mean 
and standard deviation (SD). In all cases, 
the distribution of the variable was checked 
against the theoretical models; and, in the case 
of asymmetry, we calculated the median and 
its interquartile range (IQR). The association 
between qualitative variables was evaluated 
with the c2 test or Fisher’s exact test if more 
than 25% of the expected were less than 5. 
The behavior of the quantitative variables was 
analyzed for each of the independent variables 
categorized by the Student t test. We calculated 
mean absolute effects and their 95% confidence 
Invest Educ Enferm. 2019; 37(2): e04
Francisco Martín-Rodríguez
intervals (95% CI). A logistic regression model 
was adjusted, in order to evaluate the association 
of those variables that predicted poor tolerance. 
This model allowed to identify the relationship 
between a set of explanatory variables and the 
probability of control of the variables studied. The 
calibration capacity of the model was evaluated 
with the Hosmer and Lemeshow test (p near 
1 denoting high calibration). In all hypothesis 
contrasts, the null hypothesis was rejected with a 
type I error or alpha error of less than 0.05. The 
software package used for the analysis was SPSS 
version 20.0.
Ethical aspects. The study was approved on 
April 6, 2016 by the Clinical Research Ethics 
Committee of the Río Hortega University Hospital 
of Valladolid (Spain) with registration code 
#412016. All volunteers had to read and sign 
the informed consent document.
Results
Of 47 participants, 22 were men (46.8%) and 25 
women (53.1%), with an average age of 40.2±8.7 
years. By profession, 25 were nurses (53.1%) 
and 22 medical doctors (46.8%); 26 worked 
in hospital emergency services (55.3%) and 
21 in prehospital emergency services (44.6%). 
On the IPAQ physical activity questionnaire, 25 
participants presented a low level of physical 
activity (53.2%), 14 scored a moderate level of 
physical activity (29.8%) and 8 presented a level 
of high physical activity (17%).
Table 1 shows the mean values and standard 
deviation of the parameters at baseline and 
according to the final lactic acid values.
Table 2 shows that one in four participants 
concluded the simulation with an unfavourable 
metabolic tolerance pattern. No statistically 
significant differences were found in terms of 
poor metabolic tolerance due to sex or profession 
variables.
In contrast, statistically significant differences 
could be observed in the variables of life support 
training level in environments with biological 
hazard, where the proportion of subjects with 
fatigue was greater in the category with basic 
training (37.5%). By physical activity category 
performed in the last 7 days, participants with 
a low level had ten times the probability of 
metabolic fatigue compared to those with higher 
levels of activity (44% versus 4.5%, respectively).
We adjusted a multivariate logistic regression 
model in which the variables of professional group, 
workplace (hospital emergencies or prehospital 
emergencies), age, physical activity level, body 
mass index, muscle mass and bone mass were 
included. The prediction capacity of the model 
was very good, with an AUC of 0.901 (95% CI 
0.81-0.99) and p<0.001.
The variables that predicted metabolic fatigue 
were the level of physical activity, muscle mass 
and bone mass. With decreasing physical activity 
and increasing muscle mass, tolerance worsened, 
whereas higher bone mass correlated with better 
tolerance (Table 3).
Invest Educ Enferm. 2019; 37(2): e04
Metabolic fatigue in resuscitators using personal protection equipment against biological hazard
Table 1. Distribution of vital signs and anthropometric parameters 
at baseline and according to final lactic acid values 
Variables
Baseline parameters 
Final lactate 
<4 mmol/L
≥4 mmol/L
p-value
Mean
SD*
Mean
SD
Mean
SD
Age (years)
40.2
8.7
39.3
9.3
42.9
5.8
0.210
Height (cm)
168.9
8.4
168.0
8.4
171.4
8.2
0.225
Weight (kg)
73.5
16.4
70.3
14.0
82.4
19.8
0.026
Body fat (%)
24.0
8.0
22.6
7.2
28.2
9.0
0.034
Muscle mass (%)
52.7
11.5
51.6
10.8
55.9
13.4
0.270
Bone mass (kg)
2.8
0.6
2.7
0.5
2.9
0.7
0.320
Body mass index (kg/m2)
25.5
4.2
24.7
3.6
27.9
5.2
0.024
Total water (%)
55.7
5.5
56.8
4.9
52.5
6.3
0.018
Pulse (bpm)
79.4
12.6
78.8
13.0
81.3
11.4
0.553
Systolic arterial pressure (mmHg)
129.7
13.4
127.4
13.5
136.7
10.5
0.036
Diastolic arterial pressure (mmHg)
83.5
9.4
82.5
9.7
86.3
8.0
0.225
Respiratory rate (rpm)
16.2
1.7
16.1
1.8
16.6
1.5
0.365
Temperature (ºC)
36.5
0.5
36.5
0.6
36.4
0.5
0.945
Saturation (%)
98
1.5
97.9
1.6
98.4
1.2
0.280
Hemoglobin (mg/dl)
13.7
1.4
13.7
1.4
13.7
1.4
0.992
Perfusion (%)
3.6
2.9
3.5
2.7
3.8
3.6
0.755
Glycemia (mg/dl)
114.3
21.8
112.5
18.9
119.8
29.0
0.424
Baseline lactate (mmol/L)
2.3
1.4
2.2
1.2
2.5
2.1
0.587
Lactate during CPR (mmol/L)
9.4
5.2
8.2
5.1
12.7
4.1
0.006
Final lactate (mmol/L)
3.2
1.8
2.3
0.9
5.6
1.7
<0.001
Variation between final and baseline lactate (mmol/L)
1.0
0.40
0.17
1.35
3.03
2.11
<0.001
* Standard deviation
Invest Educ Enferm. 2019; 37(2): e04
Francisco Martín-Rodríguez
Table 2. Metabolic fatigue according to study variable categories
Variable
n (%)
p-value
Total (n=47)
12 (25.5)
-
Sex
Male (n=22)
6 (27.3)
0.797
Female (n=25)
6 (24.0)
Profession
Nurse (n=25)
4 (16.0)
0.110
Doctor (n=22)
8 (36.4)
Workplace
Hospital emergency dept. (n=26)
8 (30.8)
0.360
Emergency services (n=21)
4 (19.0)
Training level in life support in biological 
hazard conditions 
Without training (n=6)
1 (16.6)
0.001
Basic training (n=8)
3 (37.5)
Advanced training (n=33)
8 (24.2)
Level of physical activity
Low (n=25)
11 (44.0)
0.008
Moderate (n=14)
1 (7.1)
High (n=8)
0 (0.0)
Level of physical activity
low (n=25)
11 (44.0)
0.002
Moderate to high (n=22)
1 (4.5)
Table 3. Variables for the logistic regression model to predict metabolic fatigue 
Variables
Odds ratio
95% CI OR
p-value
Minimum
Maximum
Physical activity (intense or moderate compared to low)
0.02
0.00
0.45
0.013
Muscle mass (units)
6.59
1.29
33.75
0.024
Bone mass (units)
0.00
0.00
0.02
0.027
Invest Educ Enferm. 2019; 37(2): e04
Metabolic fatigue in resuscitators using personal protection equipment against biological hazard
Discussion
With the generated predictive model, we know a 
priori with excellent reliability which professionals 
are going to conclude a cardiopulmonary 
resuscitation with more than 4 mmol/L of lactic 
acid in blood, an analytical value that characterizes 
the presence of metabolic fatigue, and value that 
insinuates the appearance of accidental errors of 
the workers and decrease in the quality or intensity 
of the maneuvers necessary for such a critical 
situation. The results of this study are especially 
relevant, since they allow establishing the profile 
of people who would inadequately tolerate the 
performance of a job with PPE against biological 
hazard. Knowing the possible behavior of workers 
at the physiological level, a more efficient selection 
can be made, and avoiding as much as possible 
situations of unnecessary risk in the interventions.
The anthropometric parameters behaved in the 
expected way in the face of physiological stress 
that requires increased physical activity to generate 
more bioavailable energy, with increases in muscle 
mass and water and decrease in body fat.(11)  
During any moderately intense or highly intense 
physical exercise (such as a resuscitation with a 
PPE against biological hazard), the blood pressure 
is increased to compensate the higher demand for 
energy. At the end of the exercise, a generalized 
vasodilatation results, and, as a consequence, a 
redistribution of blood, lowering blood pressure. 
After 5-6 minutes of concluding the exercise, the 
blood pressure decreases to the previous levels at 
rest, and the blood pressure decreases more to 
a level below baseline, maintaining this decrease 
for the following 5-6 hours.(12)  The physiological 
model explains these variations, as a response to 
intense exercise and the release of catecholamines, 
leading to peripheral vasoconstriction and to 
blood redistribution.(13) We found no significant 
differences by sex, group or study subgroup among 
subjects with metabolic fatigue.(14) Regarding the 
variation of lactic acid, during exercise of high 
intensity and short duration, the organism does 
not have enough oxygen immediately available, 
and must get energy through less efficient routes 
that generate more metabolic waste (glycolytic 
metabolism).(15) Consequently, high levels of lactic 
acid form that decrease muscle capacity and the 
ability to generate energy, causing early fatigue.(16)
In this study, the lactate threshold direct correlated 
with the physical form of each subject, and 
revealed substantial differences between people 
with a high level of physical activity and people 
with a sedentary lifestyle.(17) In healthy people, we 
can observe an increase in the levels of lactic acid 
during exercise of high intensity and short duration 
(more so in less trained persons). Lactic acid is 
generated as a metabolic byproduct, becoming 
recycled as it originates, to a point where the body 
is unable to recycle lactic acid and it accumulates 
above 4 mmol/L,(15)  exceeding the anaerobic 
threshold. Consequently, in high levels of lactic 
acid, the ability to generate energy decreases 
and muscle capacity decreases, appearing early 
fatigue.(18) In trained people, this threshold may 
be higher, and even more important, the capacity 
to recycle lactic acid is higher, so large quantities 
cannot accumulate.(19)
Many authors have evaluated the realization of 
techniques with protection equipment. Szarpak 
et al.(20) studied advanced airway management 
by paramedical personnel wearing protective 
suits; the same authors similarly compared the 
use of intraosseous puncture equipment with 
suit and without suit,(21) and the performance of 
conventional vascular access techniques with and 
without suit.(22) Another study by Szarpak et al.(23) 
evaluated the correct performance of external 
cardiac massage techniques on a mannequin by 
professionals in protective suits, evaluating the 
correct position, depth or quality, among other 
aspects, but none of these studies evaluated how 
this physical exertion affected the resuscitators. 
The study by Stein et al.,(24) which analyzes the 
reaction time of workers carrying PPE and their 
physiological response, should be highlighted. 
The authors describe and compare changes in 
heart rate, venous pH, pCO2, bicarbonate, lactate 
level, oxygen saturation and temperature. They 
analyze the variations of these parameters in 
19 healthy subjects, in two cases of 20 minutes 
Invest Educ Enferm. 2019; 37(2): e04
Francisco Martín-Rodríguez
of exercise without protective equipment, and 
then the variation during 20 minutes of exercise 
wearing protective suits. The heart rate and 
temperature of volunteers in protective equipment 
were substantially more elevated than in control 
condition; however, due to the size of the sample, 
the results were not statistically significant.
If we combine the physiological overload that is 
caused by the use of specific protection equipment, 
together with the effort involved in resuscitation 
tasks, working with biological hazard protection 
equipment generates discomfort and decreases 
in the level of attention and response capacity.
(24) These circumstances increase the probability 
of suffering occupational accidents and the risk 
of exacerbating pre-existing diseases, decreasing 
effective work time or generating work situations 
where it is impossible to perform the assigned 
tasks safely, for the patient, the healthcare worker 
themselves or the rest of the staff.(25)
Our research is limited to the study of the 
physiological and anthropometric parameters 
cited in the methodology, but the usefulness of 
other parameters such as cortisol, pH or insulin 
levels, among others, is not discussed. They were 
discarded from the study due to the complexity 
involved in measuring them; this limitation has 
to be taken into account in the study. Broader 
prospective studies are necessary in order to 
generalize the results and expand the parameters 
studied.
Hospital and pre-hospital emergency services 
must contemplate within their curricular design 
of competences the handling of incidents with 
biological hazard, be it as acts of chance or 
stemming from intentional terrorist acts.(26) 
Generally, we can affirm that the use of PPE 
against biological hazard is especially hard 
and arduous for workers, imposing a burden of 
additional physiological stress for the intervention.
(27) It is easy to demonstrate that work with 
protective equipment against biological hazard 
complicates technical procedures; however, so 
far, no extensive studies have shown that the use 
of PPE requires highly intense physical effort that 
prohibits working for large time intervals.(28)
We can conclude that the parameters studied 
reveal a metabolic pattern of poor physiological 
tolerance after the use of individual protection 
equipment level D in the observed sample. 
Consequently, future studies could derive a 
predictive rule that allows us to assess which 
professionals may tolerate and adapt better to 
work in a biological incident.
Invest Educ Enferm. 2019; 37(2): e04
Metabolic fatigue in resuscitators using personal protection equipment against biological hazard
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Metabolic fatigue in resuscitators using personal protection equipment against biological hazard

Metabolic fatigue in resuscitators using personal protection equipment against biological hazard.
Martín-Rodríguez, Francisco