Dr Alyani

HSNZ

case illustration introduction definition incidence clinical features aetiology and pathophysiology risk factors risk reduction and management

51 years old malay male involved with motor vehicle accident. He complaint of pain over right hip and unable to ambulate after that.

He is a chronic smoker and did not have any medical illness before.

Right hip radiograph showed comminuted fracture neck of right femur extending to lesser tubercle.

He was planned for bipolar hemiarthroplasty and posted for operation on day 3 of admission

Spinal anaesthesia was performed at spinal level of L3,L4

One and half hour of surgery,during reaming of medulary cavity, the surgeon noted hairline fracture extending to midshaft of the femur hence planned to attach the implant with bone cement

One minute after cement implantation, there was severe bradycardia, hypotension and desaturation until 78% and he went into cardiac arrest.

The surgery was stop, he was repositioned and CPR was commenced. He was intubated with ETT size 8.0mm.

After 2cycles of chest compression his conscious level improving and bradycardia and hypotension also improved.

The surgery then proceed uneventfuly

A 59-year-old Indian lady had allegedly slipped and fallen in a sitting position in the bathroom of her house.

She was admitted to hospital and was subsequently diagnosed to have a closed fracture of the neck of her left femur.

She underwent total hip replacement surgery under combined spinal epidural anaesthesia.

During the operation, upon completion of bone cementing, her heart rate suddenly dropped from 100 to 55 per minute, oxygen saturation fell to 76% and she became unresponsive.

Intravenous adrenaline and atropine were immediately given, however, her blood pressure and heart rate continued to fall

The patient was immediately sedated and intubated.

After completion of the surgery, she was transferred to the intensive care unit (ICU).

However despite full inotropic support, she did not respond and passed away approximately twelve hours post procedure

An autopsy examination was subsequently performed

Bone cement was introduced in 1970 Bone cement is a surgical material used in joint art

hroplasty surgery, filling of a bone defect, use in orthopeadic tumour surgery etc

contain 'pearls' that has pre polymerized PMMA (polymethyl metacrylate) in a powder form + liquid monomer of methyl metacrylate (MMA) = mixed with addition of catalyst that initiate polymerization of monomer --> paste.

BCIS is firstly reported after 10years of introduction of bone cement

Under reported Usually described with hip arthroplasty, however it can occur in any procedure that use cement May occur at any stage of bone surgery:femoral reamingacetabular or femoral cement implantationinsertion of prosthesisjoint reductionlimb tourniquet deflation

No agreed definition

Confluent of clinical features that includes:

HypoxiaHypotensioncardiac arrythmiasincreased pulmonary vascular resistence (PVR)cardiac arrest

Grade Characteristic

1Moderate hypoxia (spo2 <94%)

Or hypotension (SBP fall >20%)

2

Severe hypoxia (spO2 < 88%)

Or hypotension (SBP fall > 40%)

Or unexpected loss of consciousness

3 Cardiovascular collapse requiring CPR

Study Incidence of hypotension Incidence of mortality

Lafont et al 1997

n=48 (cemented THR)

2% SBP>30%

17% desaturation >5%

Coventry et al 1974

n=1684 (cemented THR) 0.06%

Ereth et al. (1992)

n=15 211(cemented THR)

n=6684 (uncemented THR)

0.12%

0%

Parvizi et al. (1999)

n=11655 (cemented THR)

n=11011(uncemented

THR)

0.09%

0%

Spectrum of severity

Increased PVRincreased pulmonary arterial pressureRV EF reduced (further distended RV pushing septum to LV, further reducing filling)reduce SVreduce COreduced MAP

transient but may persists up to 48hours

significant transient reduced in O2 saturation and

SBP

profound CVS changes

(arythmia/shock/arrest)

Features suggestive of cerebral vessel embolisation such as delirium or focal neurological deficit

emboli from the canal that escape pulm circulation or thru a potent foramen ovale

evidence by demonstrated cerebral emboli by doppler USG in 40-60% of patient undergoing joint arthroplasty

The pathophysiology and pathogenesis of BCIS is not fully understood

Suggested model: monomer mediated model embolic model histamine release and hypersensitivity multimodal model

MMA monomer in circulation causing vasodilatation but not supported as plasma MMA level after cem

ented arthroplasty < required level to cause CVS effect

Hence, it is suggested that BCIS is due to increase intramedullary pressure during cementation causing the cement to become embol

Evidence: emboli detected in RA, RV, pulmonary artery by echo, pulmonary embolization in post mortem study

Emboli content : fat, marrow, cement particles, air, bone particles, aggregates of fibrin and platelets

Mechanism :Increase intramedullary pressure as a result of: cement packing in the medullary canal using finger packing or cement guncement undergoes exothermic reaction and expands in space between prosthesis and boneprosthesis insertion with the cement inside

trapped air, medullary content under pressure forced into circulation.

Presence of the emboli will cause:

Mechanical stimulation and damage of endothelium result in reflex vasoconctriction or release of endothe

lial mediators

Embolic material may release vasoactive or proinflammatory substance that directly increased PVR, eg: thrombin / tissue thromboplasti

n

Release of chemical media

tors systemically can cause reduction in SVR such as

PG 1alfa, tissue thromboplastin

EMBOLI

Case 2 : autopsy examination Lungs : showed bone marrow elements in the blood vessels, composed of fat admixed with haemopoietic precursor cells. Fat was also observed in the pulmonary sinusoids.

Heart : showed marrow elements adherent to the endocardium

Fat, marrow elements and amorphous material were also seen within the blood vessels of the liver and kidneys.

Kidney : showed features of acute tubular necrosis.

The cause of death was disseminated microembolization as a consequence of hybrid total hip replacement surgery

Pancreas : showed acute inflammatory cell

infiltrates, patchy areas of

haemorrhage and necrosis and

surrounding fat necrosis

Fat cells in blood vessels

significant increased in plasma histamine concentration in hypotensive patient undergoing cementation (type 1 hypersensitivity)

unclear increase in c3a and c5a level (complement a

ctivation) --> potent vasoconcstrictors and bronchoconcstriction

Combination of above process Depends on patient's physiological responds

PATIENT FACTOR SURGICAL FACTOR

Old age poor preexisting physical r

eserve preexisting pulmonary hyp

ertension Osteoporosis* bony metastasis* concomittant hip fracture**Abnormal or increased vas

cular channels in marrow

previously uninstrumented femoral canal (higher risk than a revision surgery)

use of long stem femoral component

anaesthetic volatile agent may be assoc with greater haemodynamic changes for the same embolic load

avoidance of nitrous oxide to avoid exacerbating air embolism

avoiding intravascular volume depletion high level intraoperative vital signs monitori

ng in high risk patient such as IABP,central venous catheter

Do a medullary lavage Good homeostasis before cement

insertion Minimizing the length of prosthesis Using non cemented prosthesis Venting the medullary canal Mixed the cement in partial vacuum

rather than at atmospheric pressure

Communication between surgeon and anaesthetist before the operation is performed especially in high risk patient

Fall in ET C02 is the first indicator of BCIS In awake patient, early sign may include

dyspnoea and altered sensorium Management mainly empirical and according

to the presentation If BCIS is suspected, inspired oxygen should

be increased to 100% To treat CVS collapse as RV failure –

aggressive recussitation with IV fluid is recommended

Inotropic support if needed Administration of sympathetic alfa 1 agonist

Bone cement implantation syndrome, A.J. Donaldson, HE Thomson, NL Harper, NW Kenny, Manchester UK, British Journal of Anaesthesia, 2009

BCIS – A Case Report, Anish KA, Suranjith Sorake, S.Padmanabha, Mangalore India, IOSR Journal of Dental and Medical Sciences, December 2013

Case report, Bone Cement Implantation Syndrome, Razuin R, Effat O, Shahidan MN, Shama DV, MFM Miswan, Faculty of medicine, UiTM, Hosp Sungai Buloh, Malaysian Journal of Pathology, 2013

Bone Cement and Implication for anaesthesia, Gautam Khanna, Jan Cemovsky, Oxford Journal , Feb 2012

Special thanks to Dr Rohani