Vital Signs (Nursing)

• Consciousness, breathing and circulation.

• We refer to the repeated or permanent monitoring of the patient's physiological functions and the operation of the devices used to support these functions as monitoring for the purpose of:

• Early detection of abnormalities of physiological functions.
• Facilitating consideration of possible medical intervention.
• Evaluation of treatment effectiveness.

• The human factor is irreplaceable.
• The best and safest monitoring is a nurse.

!!! If a patient looks clinically unwell, they are most likely unwell, regardless of the presence of good values.

Side effects

• Inaccurate measurements or tracking errors of evaluated indicators.
• Device errors in the evaluation of the sensed signals or data.
• Artifacts during measurement.
• Possible complications and pain associated with the use of the monitoring technique.
• Increase in costs (technology, personnel, repairs, recording and data storage).
• Focusing more on the monitors than the patient.

Monitoring

• Blood circulation: ECG, blood pressure, hemodynamic profile.
• Breathing: ventilation parameters (EtCO₂, respiratory rate, respiratory volume, minute ventilation), tissue oxygenation parameters (SpO₂, paO₂, pvO₂, mucosal pH and paCO₂, microdialysis).
• CNS status: GCS, ICP, microdialysis, jugular oximetry.
• Organ perfusion: CPP, IAP.
• State of sedation and muscle relaxation.

Monitoring during anesthesia

• The operation and the anesthesia itself affect the overall condition of the patient, his internal environment, cardiovascular and respiratory systems.
• Careful monitoring makes it possible to prevent or timely treat disorders of the operated patient's physiological state and thus prevent subsequent postoperative complications or even the death of the patient.

• The anesthesiologist should be present during the entire course of anesthesia.
• Patient monitoring must be started before the induction of anesthesia and must be completed only after the patient is safely removed from anesthesia.
• Standard monitoring should always be performed regardless of whether it is general anesthesia or regional anesthesia.
• The course of anesthesia and vital signs should be recorded at regular intervals.
• All monitoring devices must be checked before surgery and the anesthesiologist should be adequately trained in the use of these systems.

• Monitoring in anesthesiology is a basic prerequisite for the safe administration of anesthesia.
• Monitoring can be done with your senses or using devices.

• Do not underestimate clinical monitoring.
• Do not panic at "suspicious" values - often a malfunction of the device.

!!But not all "suspicious" values mean a malfunction of the device, often the patient is really sick.

• !!!We treat the patient, not the monitor !!

Consciousness

• Consciousness monitoring is ALWAYS subjective.
• Scale bars are used.
• None of the scales are ideal.

• The Glasgow Coma Scale (also pediatric) and scoring according to Beneš are most often used.

QUALITATIVE disorders

• Delirium.
• Agitation.
• Apathy.
• Obnubilation.

QUANTITATIVE DISORDERS

• Somnolence

• Symptoms of sleepiness are characteristic, when the person in question can be woken up - he does not speak spontaneously, has a slow response to questions and only responds to an algic (painful) stimulus.

• Sopor'

• Mumbling unintelligible words, does not respond to questions, can only be awakened by a strong algic stimulus.

• Coma

• The most severe disorder of consciousness. In this state, the eyes may be slightly open and give the impression of observing the surroundings, there is no reaction to sounds, there are no spontaneous movements, they do not speak.

During anesthesia

• Indirect marks are tracked.
• Moves.
• Ciliary reflex and pupil.
• Pressure and pulse.
• Sweating.
• Respiratory rate.
• Directly measured grades - BIS.

• Bispectral index – EEG analysis.
• Developed as an objective method for determining the depth of anesthesia.
• The index has very good validity proven by studies in adult patients during inhalation anesthesia. The limit of the method is the large variability of values for adequate analgosedation.
• Especially anesthesia for taking higher doses of opiates.
• Often also forensic use (USA) - lawsuits for perioperative vigilance.
• Keep 60-80 during anesthesia.

100 points = full consciousness.

80-65 points = sedation.

65–40 = moderate to deep anesthesia.

under 40 = coma.

ISP Monitoring

• Intracranial pressure is determined by three components: brain tissue, blood in the cerebral vascular bed and cerebrospinal fluid.
• Normal values are in the range of 7-15 mmHg for adults, 15-20 mmHg for children.
• Always introduced on the damage side.
• Preference for intraparenchymal approach.

Tissue oxygenation – Licox

• White matter sensor.
• Often combined with ICP, temperature and cerebral blood flow measurements.
• It is introduced into the ischemic penumbra.
• Standard 35-50 torr.
• Critical value 5-20 torr.

Blood flow through the brain

• Monitoring, e.g. by the Hemedex system.
• Common sensors.
• Standard: 50-60 ml/100 g/min.
• Ischemic threshold: 20 ml/100 g/min.

Microdialysis

• Lactate/pyruvate – manifestation of anaerobic metabolism – norm up to 30.
• Glycerol – manifestation of the breakdown of bb. – standard 80–100.
• Glutamate-excitotoxicity.
• Experimental method.

Saturation in jugular bulb

• Monitors oxygen consumption by the brain.
• Norm 55-70%.
• Increase - loss of self-regulation.
• Reduction - reduced supply, increased consumption.
• Lactate can also be monitored.

Neuromuscular transmission monitoring

• Most often the Train of four method – a group of 4 impulses.
• The device sends short electrical pulses to the ulnaris nerve and measures the response accelerometrically.
• The last/first ratio (size) or the number of twitches is important.
• Attention affected by temperature!

Breathing monitoring

• Ventilation parameters (Et CO2, respiratory rate, respiratory volume, minute ventilation).
• Tissue oxygenation parameters (SpO2, pa O2, pvO2, mucosal pH and pCO2, microdialysis).
• Monitoring of the mechanics of ventilation (retraction, lag of one half of the chest, airway obstruction,...).
• Breathing frequency.
• Depth of breathing (tidal volumes).
• Ability to maintain a clear airway.

Instrument monitoring

• Comprehensive measurement of ventilation when connected to a ventilator (tidal volumes, frequencies, spirometric curves, pressures, pauses, etc.).
• Tidal volume, respiratory rate, airway pressure, PEEP size, O2 percentage.

Measured parameters

• Tidal volume – approx. 6–10 ml/kg.
• Respiratory rate – 10–16/min.
• Airway pressure – LM up to 15-18 cm H₂O, OTI up to 30 cm H₂O.
• Inspiratory time 1.2 to 1.5 sec.
• Ratio I:E 1:2 or Ti 33%.
• Pause 10% or 0.2-0.4sec.
• PEEP base 5cm H20.
• Trigger −0.5 to −1 cm H₂O or 3-5 l/min.
• FiO2 0.4; depending on the situation.

Capnometry

• It is a basic element of safe anesthesia with airway management.
• Enables monitoring of unwanted esophageal intubation, tracheal tube/LM dislocation, inadequate ventilation.
• Can also be used with a sealing face mask.
• The principle is absorption spectrometry.
• Standard 4.3-6.3 kPa (34-48 mmHg).
• CO₂ production increases by hypoventilation, temperature, laparoscopy, rebreathing, pressure rise!
• CO₂ production is 'reduced by hyperventilation, BP drop, embolization, OTI kink, technical problem (circuit leak).

Pulse oximetry

• A non-invasive method for measuring the amount of oxygen bound to hemoglobin.

• Oxygenated and non-oxygenated hemoglobin have different absorption properties for light of different wavelengths. A pulse oximeter therefore illuminates the tissue with red and infrared light. The signal passing through the tissue is affected by the absorption properties of hemoglobin and the heart rate. We measure these signals and their ratio will allow us to determine the oxygen saturation of the blood.

• Normal saturation values are between 90-100%.

!!!Beware of painted nails, CO poisoning - the oximeter shows falsely high values, in patients with peripheral blood flow disorders or with arrhythmias we get falsely low values. !!!Watch out for cold fingers and pressure measurement/numbness of the limb.

Astrup

• Used less under anesthesia.
• For long operations, it shows the state of the internal environment.
• For long-term sitting, where it is not possible to monitor capnometry, check the adequacy of ventilation.
• The main focus of the method is in intensive care.

• pH (7.36–7.44).
• CO₂ (4.8–5.9 kPa).
• O₂ (10.4–13.3 kpa).
• HCO₃⁻ (21.7–27.3 mmol/l).
• BE (− 2.5–2.5 mmol/l).
• SatO₂ 02 90–97.5%.

Circulation

• Each contraction of the heart muscle is accompanied by the creation of a weak electrical voltage, which spreads to the surface of the body, where it can be sensed EKG.
• When monitoring during anesthesia V1 and II leads - the possibility of detecting up to 90% ischemia (5 leads on the chest).
• The simpler one can only do basic, it has no chest.
• The basis is to load and understand the ECG well.

Central venous pressure

• CVP can be measured using a central venous catheter usually inserted into the area of the superior vena cava.
• CVP is the pressure exerted on the wall of the superior vena cava in the region of its mouth into the right atrium.
• Corresponds to the pressure value in the right atrium and, if there is no stenosis or regurgitation of the tricuspid valve, it reflects the end-diastolic pressure in the right ventricle (RVEDP) or right ventricular preload.
• Normal CVP is between 2-8 mmHg (3-10 cm H₂O).
• The value of CVP is understandably influenced by the value of intrathoracic pressure and it is correlated with the used ventilation mode and modulation of controlled breathing.

Measurement of hemodynamics

• By direct measurement of hemodynamic parameters and values derived from them.
• More accurate determination of the cause of circulatory instability.
• Checking the effectiveness of therapy.
• Invasive monitoring:

• Swan-Ganz catheter.
• PICCO.
• Vigilio.

• Non-invasive monitoring:

• Transthoracic bioimpedance.
• Esophageal ECHO.

Cardiac output

• Basic determinant of tissue perfusion.
• CO = SV x HR
• Factors influencing SV (stroke volume).

• preload,
• myocardial contractility,
• afterload.

Systemic Vascular Resistance

• SVR = (MAP – CVP) x 80 / CO.
• Good blood pressure does not necessarily mean good cardiac output (vascular resistance may increase while cardiac output decreases).

Delivery of oxygen to the tissues

• DO₂ [ml/l] = CO x [(Hb x SaO₂ x 1.39) + (PaO₂ x 0.003) ] → a complex formula, but a simple principle.

• By increasing the saturation, I will increase the supply of oxygen to the organism by a unit of %.
• By increasing Hb, I increase the supply of oxygen to the organism by tens of %.
• By increasing the CO, I will increase the oxygen supply by hundreds of %.

Microcirculation

• Difficult to evaluate.
• One of the markers of a well-functioning perfusion is diuresis.
• Dysfunction of microcirculation-marbling.
• Capillary return - cold acre!

Swan-Ganz Catheter

• Indications:

• Necessity of high-volume replacements in hypovolemic, burn or hyperdynamic-septic shock.
• Complications of acute myocardial infarction - heart failure resistant to conventional therapy.
• Rupture of the interventricular septum and papillary muscle of the mitral valve with acute mitral insufficiency.
• Right ventricular infarction.
• Acute respiratory distress syndrome - ARDS.
• Multiorgan failure etc.

• Measurement of pressures in the right atrium or CVP.
• Pulmonary artery pressure.
• Wedge pressure (PAOP) filling pressure of the left heart.
• Intermittent measurement of cardiac output by the thermodilution method.
• Above standard continuous measurement of cardiac output.
• Saturation of venous blood with oxygen.
• Right ventricular ejection fraction and end-diastolic volume (REF, RVEDV).

PICCO'

• The principle of the method is thermodilution measurement and pulse contour analysis.
• Allows you to measure and especially calibrate values.
• That is as with the Swan-Ganz catheter, the values are absolute (not just a trend).

Vigileo'

• Works on the principle of Pulse contour analysis.
• Curve records in memory and calculation and modeling of basic hemodynamic functions using an algorithm.

CI, SVRI, SVV.

• Rather than absolute values, it is good to follow the trend!

LiDCO'

• LiDCo works on the principle of pulse contour analysis.
• However, it is LiCl calibrable.
• Then the trend monitor becomes an absolute number monitor.
• LiDCO rapid is a perioperative monitor of trend values - not calibratable.
• Same values as Vigileo.
• Its great advantage is transportability.
• It is small and usable during anesthesia.
• The downside is only the trend values.
• Relatively few values for intensive care.

Body temperature

• Man is a warm-blooded animal.
• His body temperature is controlled by metabolic processes in the range of 36-37 °C.
• Body temperature below 36 °C is subnormal, 37-38 °C is considered subfebrile and temperature above 38 °C is considered fever - febrile, hyperpyrexia - 40-41 °C.
• The main thermostat is located in the hypothalamus.
• IL-1 and prostaglandins are temperature regulators.
• Morning minimum between 4.-6. an hour.
• Afternoon maximum between 16.-18. an hour.

• In the mouth (oral temperature), 0.30 °C higher.
• In the anus (rectal temperature) by 0.50 °C higher - when using a heated sensor, introduce a deep-stool insulator!
• In the vagina (vaginal temperature), which is affected by the hormonal changes of the ovarian cycle, it increases by 0.50 °C during ovulation.
• The temperature in the esophagus - better corresponds to the temperature of the body's core, need to introduce deep enough-injury!
• The temperature of the eardrum – corresponds to the temperature in the head (brain) – be careful of external cooling (water).
• Bladder temperature - urine insulator.
• Arterial blood temperature.

• Temperature measurement is one of the basic monitoring parameters during anesthesia or in intensive care units.
• The temperature should be measured in most patients during anesthesia for more than 30 min.
• Classic thermometer (no more mercury!) - roughly the temperature in the armpit.
• Infrared digital thermometers - depends on blood flow, good for orientation, most accurate tympanic thermometers.
• Temperature sensors - they are placed under the patient, in the rectum, in the esophagus (disposable x sterilizable).
• Temperature sensors in the urinary catheter - expensive.
• Sensors in PiCCO devices and Swan-Ganz catheter.

Diuresis

• The normal range of diuresis is approx. 0.5-1 ml/kg/hour.
• During anesthesia due to altered blood supply to the splanchnic and often UPV decrease.
• Diuresis monitoring is important for long procedures (NCH, cardio) and for procedures with large blood losses.
• urine color is important.

Links

Source

• MUDr. VOJTÍŠEK, Petr. Vitální funkce [přednáška k předmětu Modul Anestezie, obor Sestra pro intenzivní péči – specializační studium, Vyšší odborná škola zdravotnická a Střední škola zdravotnická]. Ústí nad Labem. 2012-05-11.