Local tissue injury from external compressive force — fractures, lacerations, tissue necrosis
Crush syndrome
Systemic consequences of muscle breakdown (rhabdomyolysis) following prolonged compression — AKI, hyperkalaemia, metabolic acidosis, DIC, compartment syndrome
Crush syndrome occurs when significant muscle mass (usually ≥1 hour of compression on large muscle groups) releases intracellular contents — myoglobin, potassium, phosphate, and lactate — into the circulation upon extrication.
High risk of AKI — intensive monitoring; nephrology involvement
Peak 24–48h
CK peaks 24–48 hours after injury; continue monitoring until declining
"Smiling Death" — The Extrication Paradox
A patient trapped for hours may appear well — smiling, talking, haemodynamically stable. Upon extrication, massive release of potassium and myoglobin from ischaemic muscle causes SUDDEN death from cardiac arrhythmia within minutes. This is called "smiling death" or "extrication death."
PREVENTION: Start aggressive IV fluid resuscitation BEFORE extrication if safe to do so. Target: 1–1.5 L/hour Ringer's lactate or normal saline.
ECG Changes — Hyperkalaemia
Immediately after extrication, monitor ECG continuously:
Serum K⁺
ECG Changes
5.5–6.0 mmol/L
Tall, peaked T-waves (earliest sign)
6.0–7.0 mmol/L
PR prolongation, QRS widening, P-wave flattening
>7.0 mmol/L
Sine wave pattern, VF, asystole
Peaked T-waves = EMERGENCY. Act before K⁺ result returns from lab. Treat empirically if ECG changes present.
Urine Assessment
Dark brown/tea-coloured urine = myoglobinuria — pathognomonic of rhabdomyolysis
Note: dipstick tests positive for "blood" (myoglobin cross-reacts) but no RBCs on microscopy
Urine alkalinisation: add sodium bicarbonate to IV fluids; maintain urinary pH >6.5
Bloods: FBC, U&E, calcium, phosphate, CK, lactate, LFTs, coagulation, ABG, type and screen
Catheter: urinary catheter for accurate hourly measurement; assess urine colour
Hyperkalaemia Treatment Summary
Drug
Dose
Action
Onset
Calcium gluconate 10%
10mL IV over 2–5 min
Cardiac membrane stabilisation
Immediate (1–3 min)
Insulin + Dextrose
10U + 50g glucose IV
Shifts K⁺ into cells
15–30 min
Sodium bicarbonate
50–100 mmol IV
Alkalinisation shifts K⁺ intracellularly
15–30 min
Salbutamol nebuliser
10–20 mg nebulised
β₂ stimulation shifts K⁺ into cells
15–30 min
Resonium / patiromer
Oral/rectal
K⁺ removal from body
Hours
Haemodialysis
Emergency RRT
Definitive removal
Immediate on dialysis
Compartment Syndrome Management
5 Ps of compartment syndrome: Pain (on passive stretch), Pallor, Paraesthesia, Paralysis, Pulselessness
Measure compartment pressure: >30 mmHg (or within 30 mmHg of diastolic BP) → fasciotomy
Do NOT elevate the limb above heart level — this reduces perfusion pressure and worsens ischaemia
Remove all circumferential bandages, plaster casts
Fasciotomy = emergency surgical decompression of compartment fascia
Post-fasciotomy wound care: open wounds until swelling resolves; secondary closure or skin graft
Pain on passive stretch is the EARLIEST and most sensitive sign of compartment syndrome. Do not wait for pulse loss — irreversible muscle death occurs before pulses are lost.
Acute Kidney Injury (AKI)
AKI affects up to 50% of patients with significant rhabdomyolysis
Mechanisms: myoglobin tubular obstruction, direct tubular toxicity (ferrihemate), renal vasoconstriction
Prevention: aggressive early fluid resuscitation is the most effective intervention
If AKI develops despite fluids: nephrology consultation for haemodialysis
Simultaneous clotting + fibrinolysis → organ microthrombi + haemorrhage
Signs: bleeding from IV sites, haematuria, petechiae, prolonged PT/APTT
Treatment: FFP (for coagulopathy), platelets (<50 with active bleeding), cryoprecipitate (fibrinogen <1.5 g/L)
Treat underlying cause — control of haemorrhage and tissue injury
Metabolic Acidosis
Lactic acid + intracellular acidosis from ischaemic muscle
Worsens hyperkalaemia (acidosis shifts K⁺ out of cells)
Monitor ABG for pH, bicarbonate, and base deficit
IV sodium bicarbonate: corrects acidosis AND alkalinises urine (protective for renal tubules)
Severe metabolic acidosis (pH <7.2) despite fluids = escalate for RRT consideration
Crush Injury in GCC Industrial Context
The GCC has one of the world's largest construction and industrial workforces. Migrant workers (primarily from South Asia and Southeast Asia) constitute the majority and are most at risk of industrial crush injuries.
Construction site collapses — scaffolding falls, building collapses, trench cave-ins
Oil and gas industry — valve/machinery entrapment; pipeline accidents
Mina tunnel crush (Hajj 1990) — historically significant GCC mass crush event
Confined space accidents in petrochemical facilities
Road traffic accidents — vehicle entrapment common cause
Migrant Worker Vulnerability
Language barriers delay reporting of injuries and symptoms
Fear of job loss may delay hospital presentation
Inadequate personal protective equipment (PPE) in some worksites
Calcium gluconate = first-line for cardiac protection in hyperkalaemia (membrane stabiliser)
Compartment syndrome: pressure >30 mmHg → fasciotomy; do NOT elevate limb
Dark urine = myoglobinuria; dipstick positive for blood but no RBCs on microscopy
Common Exam Traps
Do NOT elevate limb with compartment syndrome — reduces perfusion, worsens ischaemia
Calcium gluconate stabilises cardiac membrane but does NOT reduce serum K⁺ levels — need insulin/dextrose to shift K⁺
Start IV fluids BEFORE extrication if possible — not after
Pain on passive stretch = earliest sign of compartment syndrome — do not wait for absent pulse
GCC Clinical Practice Insights
Construction Site Protocols in UAE and Qatar +
UAE (OSHAD) and Qatar (MOL) have occupational safety frameworks requiring risk assessment, PPE provision, confined space procedures, and emergency response plans at all construction sites. Despite frameworks, implementation is variable. Nurses assessing crush injury patients should document occupational exposure history to support incident reporting and potential workers' compensation claims.
Haemodialysis Capacity for Crush Syndrome in GCC +
Major GCC hospitals maintain nephrology departments with both intermittent haemodialysis (IHD) and continuous renal replacement therapy (CRRT) capability. CRRT is preferred for haemodynamically unstable crush syndrome patients with AKI. Emergency haemodialysis should be available 24/7 at Level 1 trauma centres in the GCC. Nurses must be familiar with vascular access (CRRT catheter) care, circuit alarms, and citrate anticoagulation protocols.
Fasciotomy Post-Op Nursing Care +
Following fasciotomy, wounds are left open to allow decompression. Nursing care includes: moist wound management, wound VAC (negative pressure wound therapy) in some centres, daily wound assessment, pain management (significant post-fasciotomy pain is expected), monitoring neurovascular status of the limb (sensation, movement, capillary refill, pulse oximetry), and infection prevention. Secondary closure or skin grafting is performed when swelling resolves (typically 5–10 days).
Mina Tunnel Crush — Learning for GCC Disaster Medicine +
The 1990 Mina tunnel disaster (1,426 deaths) provided critical learning for GCC mass casualty and crush injury management. Key lessons: need for pre-positioned IV fluid capability at high-risk sites, medical triage teams trained in crush syndrome, rapid access to dialysis capacity, and clear communication protocols between field teams and hospitals. Saudi Arabia's Hajj medical mission has incorporated these lessons into annual planning.
Practice MCQs
Q1. A construction worker has been trapped under rubble for 3 hours. He is conscious and talking. Rescue teams are ready to extricate him. What is the MOST important nursing/paramedic action BEFORE extrication?
Correct answer: B — "Smiling death" is the paradox of crush injury — a patient appears well while compressed, but extrication suddenly releases potassium and myoglobin from ischaemic muscle causing fatal hyperkalaemia and cardiac arrest within minutes. Pre-extrication IV fluids dilute the potassium load, protect the kidneys, and are the single most important intervention before removal of the compressive force.
Q2. A patient with crush syndrome has serum potassium of 7.2 mmol/L. ECG shows widened QRS complexes and peaked T-waves. Which drug should be given FIRST?
Correct answer: C — When ECG changes from hyperkalaemia are present (widened QRS, peaked T-waves), the immediate priority is cardiac membrane stabilisation with calcium gluconate. This does NOT reduce serum K⁺ but protects the heart from arrhythmia while other measures (insulin/dextrose, bicarbonate) take effect to shift K⁺ intracellularly. Calcium takes effect in 1–3 minutes.
Q3. A patient recovering from crush injury develops severe forearm pain, especially on passive finger extension, with tense swelling and paraesthesia in the hand. Compartment pressure is 35 mmHg. What is the correct management?
Correct answer: C — Compartment syndrome with pressure >30 mmHg (or within 30 mmHg of diastolic BP) AND clinical signs (pain on passive stretch, paraesthesia) = emergency fasciotomy. Do NOT elevate the limb — this reduces arterial perfusion pressure and worsens ischaemia. Ice is harmful (vasoconstriction). Diuretics do not relieve compartment pressure. Immediate surgical referral is required.
Q4. A patient with rhabdomyolysis has dark brown urine. Urinary dipstick tests strongly positive for blood but urine microscopy shows no red blood cells. What is the explanation?
Correct answer: C — Dark brown urine with dipstick positive for blood but no RBCs on microscopy = myoglobinuria. Myoglobin cross-reacts with the peroxidase-based dipstick haemoglobin reaction. This is a classic examination scenario. The presence of myoglobinuria confirms significant rhabdomyolysis and should trigger aggressive fluid resuscitation to target UO 200–300 mL/hour and prevent AKI.