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Vital Signs and Physiological Parameters

Part of the DOH (UAE) study roadmap. Medical Knowledge topic medica-002 of Medical Knowledge.

Vital Signs and Physiological Parameters

Vital signs are the cornerstone of patient assessment and the most frequently performed nursing activity in any UAE healthcare facility. They provide objective, measurable data about a patient’s physiological status and serve as the primary indicators of clinical deterioration or improvement. The DOH (UAE) examination tests your ability to accurately measure, interpret, and respond to vital sign abnormalities, with particular emphasis on recognising the significance of trends and deviations from normal. In the UAE’s high-acuity hospital environment, early recognition of vital sign abnormalities is critical for timely medical intervention.


🟢 Lite — Quick Review (1h–1d)

Rapid summary for last-minute revision before your exam.

Normal Vital Sign Ranges (Adult):

ParameterNormal Range
Temperature36.5–37.5°C (97.7–99.5°F)
Pulse (HR)60–100 bpm
Respiratory Rate12–20 breaths/min
Blood Pressure< 130/80 mmHg (systolic/diastolic)
SpO₂95–100% (on room air)
MAP70–100 mmHg

Mean Arterial Pressure (MAP): MAP = (Systolic + 2×Diastolic) ÷ 3 Example: BP 120/80 → MAP = (120 + 160) ÷ 3 = 93 mmHg (normal) Minimum MAP for adequate organ perfusion: 65 mmHg

Key Thresholds Requiring Immediate Action:

  • HR < 50 or > 130 bpm
  • RR < 8 or > 30 breaths/min
  • BP < 90/60 or > 180/110 mmHg
  • SpO₂ < 90%
  • Temperature > 39.5°C or < 35°C

⚡ Exam Tip: When vital signs are abnormal, always assess the patient clinically — not just the numbers. A “normal” set of vitals in a visibly distressed patient is still a concerning finding.


🟡 Standard — Regular Study (2d–2mo)

Standard content for students with a few days to months.

1. Temperature — Assessment and Interpretation

Sites and Normal Ranges:

  • Oral/Sublingual: 36.5–37.5°C
  • Tympanic (ear): 36.5–37.8°C (reflects core temperature; used widely in UAE)
  • Rectal: 37.0–37.8°C (closest to core; reserved for specific indications)
  • Axillary: 36.5–37.2°C (least accurate; adds ~0.5°C)
  • Temporal artery: 35.8–37.8°C (non-invasive, used in paediatrics)

Fever Patterns — Clinical Significance:

PatternDescriptionAssociated Conditions
ContinuousFever stays above normal; minimal fluctuationTyphoid fever, pneumonia, UTIs
RemittentFever fluctuates >2°C but never reaches normalMost infections
IntermittentFever peaks and returns to normalMalaria (tertian/quotidian patterns)
RelapsingFever-free periods between febrile episodesBrucellosis, Borrelia infections
Pel-EbsteinCyclical fevers every 3–7 daysHodgkin’s lymphoma

Hypothermia: Core temperature <35°C. Causes: Cold exposure, sepsis (particularly in elderly), hypothyroidism, hypoglycaemia, drug intoxication. Signs: Shivering (early), confusion, bradycardia, loss of coordination.

Hyperthermia: Core temperature >40°C — medical emergency. Causes: Heat stroke, neuroleptic malignant syndrome, malignant hyperthermia.

2. Pulse — Assessment Beyond the Rate

Sites and Their Clinical Use:

  • Radial (wrist): Most common; used for routine monitoring
  • Carotid (neck): Used in cardiac arrest assessment; do not massage in elderly (carotid sinus hypersensitivity → bradycardia, syncope)
  • Apical (5th intercostal space, midclavicular line): Used when radial pulse is irregular (to detect pulse deficit)
  • Brachial (antecubital fossa): Used for BP measurement; blood transfusion
  • Dorsalis pedis/Posterior tibial (foot): Peripheral vascular disease assessment
  • Femoral: Paediatric assessment; cardiac arrest in infants

Pulse Rhythm:

  • Regular: Evenly spaced beats
  • Regularly irregular: Pattern repeats (e.g., Wenckebach/second-degree AV block — progressively shorter PR interval until dropped beat)
  • Irregularly irregular: No pattern (e.g., atrial fibrillation — highly prevalent in elderly Emirati patients)

Pulse Character:

  • Full/bounding: Hypertension, anxiety, hypervolaemia
  • Weak/thready: Hypovolaemia, shock, poor cardiac output
  • Pulsus bisferiens (double peak): Hypertrophic obstructive cardiomyopathy
  • Pulsus paradoxus (>10 mmHg fall in BP on inspiration): Cardiac tamponade, severe asthma, COPD

3. Respiratory Assessment

What to Assess:

  • Rate (count for 60 seconds — the most accurate method)
  • Depth: Shallow, normal, deep (Kussmaul breathing = deep, rapid, sighing — DKA, renal failure)
  • Rhythm: Regular, Cheyne-Stokes, Biot’s, ataxic
  • Effort: Use of accessory muscles, nasal flaring, retractions, stridor, wheezing
  • Sound: Stridor (upper airway obstruction — medical emergency), wheezing (lower airway), crackles (fluid/secretions in alveoli)

Cheyne-Stokes vs Biot’s Breathing:

PatternDescriptionCauses
Cheyne-StokesGradually increasing then decreasing depth with periods of apnoeaBrainstem compression, severe heart failure, drug overdose
Biot’s (ataxic)Irregular, unpredictable pattern with unpredictable apnoeic periodsBrainstem injury (cerebellar tonsillar herniation)

4. Blood Pressure — More Than Systolic/Diastolic

Hypertension Classification (UAE follows WHO/ISH):

  • Normal: < 130/80
  • Elevated: 130–139 / 80–89
  • Stage 1 HTN: 140–159 / 90–99
  • Stage 2 HTN: ≥ 160 / ≥ 100
  • Hypertensive Crisis: > 180/120 → requires immediate medical review

Hypertension is endemic in the UAE — estimated 30–40% of adults have hypertension. Major contributing factors include high salt intake in traditional cuisine, obesity, diabetes, and sedentary lifestyle.

Orthostatic Hypotension:

  • Drop of ≥ 20 mmHg systolic or ≥ 10 mmHg diastolic on standing from supine
  • Check in patients on antihypertensives, diuretics, elderly patients, and those with dizziness/syncope
  • Method: Measure BP supine; wait 5 minutes; measure standing at 1 and 3 minutes

Pseudohypertension: Falsely elevated BP due to rigid, calcified arteries (elderly) — difficult to compress with cuff.


🔴 Extended — Deep Study (3m+)

Comprehensive coverage for students on a longer study timeline.

5. Early Warning Scores (EWS) — UAE Practice

UAE hospitals use Early Warning Score (EWS) or Modified Early Warning Score (MEWS) systems to identify deteriorating patients and trigger escalation of care.

Parameters in MEWS:

Score3210123
HR<4040–5051–100101–110111–130>130
SBP<7070–8081–100101–199>200
RR<66–910–1415–2021–30>30
Temp<3535–38.4>38.5
AVPUAlertVoicePainUnresponsive

Score ≥ 5 = Urgent review; Score ≥ 7 = Emergency/ICU review

National Early Warning Score 2 (NEWS2) — used in many UAE facilities:

  • Includes: Resp rate, SpO₂, Air or O₂, SBP, Consciousness, Temperature, Heart Rate
  • Higher scores trigger: Urgent nursing review, physician review, or critical care outreach team

6. Advanced Monitoring — UAE ICU Context

Arterial Line Monitoring:

  • Continuous BP monitoring; used in critically ill patients
  • Site: Radial artery (preferred), femoral, brachial, dorsalis pedis
  • Waveform assessment: Damping (loss of waveform detail) indicates arterial line problem
  • Mean arterial pressure (MAP) is the most reliable measurement from an arterial line

Central Venous Pressure (CVP):

  • Measured via central line (subclavian, internal jugular, femoral)
  • Reflects right atrial pressure/venous return
  • Normal: 2–8 mmHg (or 4–12 cmH₂O)
  • Limitations: Poor correlation with left-sided filling pressures in cardiac patients; trending is more useful than single values

Cardiac Output Monitoring:

  • Thermodilution (Swan-Ganz/PA catheter), lithium dilution, pulse contour analysis
  • Less commonly used today due to less invasive alternatives
  • Used for: Septic shock, cardiogenic shock, complex cardiac surgery patients

7. Special Considerations in UAE Population

Diabetes and Blood Pressure:

  • UAE has one of the highest rates of diabetes globally (~17% adults)
  • Diabetic autonomic neuropathy can cause abnormal BP regulation (postural hypotension, labile hypertension, impaired baroreceptor reflex)
  • BP targets for diabetics may be more stringent (<130/80) to reduce cardiovascular risk

The Gulf Climate and Vital Signs:

  • Extreme heat in UAE (summer temperatures 40–50°C) increases risk of heat exhaustion and heat stroke
  • Patients taking diuretics, antihypertensives are at increased risk of dehydration and electrolyte imbalance
  • Environmental assessment is critical in the summer months

Exam Watch: A question where a patient’s BP is 90/60 mmHg with tachycardia, cool extremities, and altered mental status should immediately trigger recognition of hypovolemic shock. The priority action is to ensure adequate airway, administer oxygen, establish IV access, and notify the physician immediately. Never ignore hypotension in a symptomatic patient.


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