Trauma in pregnancy Flashcards
Trauma in Pregnancy
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1 Trauma is a leading cause of maternal mortality and presents unique challenges that require urgent multidisciplinary input to optimise outcomes.
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2 Initial management must be focused on maternal assessment, resuscitation and stabilisation, and requires significant modification of contemporary trauma care principles.
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3 Establishing maternal stability may not be possible without obstetric intervention and emptying of the uterus.
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4 Concerns regarding fetal irradiation should not delay standard trauma imaging.
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5 Fixed-ratio blood product replacement strategies during massive transfusion may not be appropriate in advanced pregnancy.
Trauma in Pregnancy
*
1 Trauma is a leading cause of maternal mortality and presents unique challenges that require urgent multidisciplinary input to optimise outcomes.
*
2 Initial management must be focused on maternal assessment, resuscitation and stabilisation, and requires significant modification of contemporary trauma care principles.
*
3 Establishing maternal stability may not be possible without obstetric intervention and emptying of the uterus.
*
4 Concerns regarding fetal irradiation should not delay standard trauma imaging.
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5 Fixed-ratio blood product replacement strategies during massive transfusion may not be appropriate in advanced pregnancy.
Clinical decision-making in such scenarios is complicated by many factors:
Trauma and pregnancy
(i)
The needs of both mother and fetus must be considered.
(ii)
Multiple and dynamic anatomical and physiological changes of pregnancy mandate modification of trauma management principles.
(iii)
Life-threatening obstetric complications can occur even after seemingly minor trauma and may require urgent delivery of the fetus.3
(iv)
Fetal injury can predominate over that of the mother.4
(v)
Obstetric teams may be unfamiliar with the emergency department (ED) environment and contemporary management of major trauma.
(vi)
Emergency department and trauma teams may be unfamiliar with aspects of emergency obstetric care, as this usually takes place in dedicated areas distant to the ED
Prep for maternal trauma
Tuma call (T–15 min)
Team assembly and briefing
Urgently request obstetric and neonatology attendance.
Discuss standard care modification.
Team leader assigns roles∗
Manual uterine displacement and
fetal heart rate assessment (nurse/midwife)
Resuscitative hysterotomy team (obstetrics)
Neonatal resuscitation team (neonatology)
Preparation of equipment and drugs
Resuscitative hysterotomy pack preparation
Neonatal resuscitation equipment preparation
Contact haematology and transfusion laboratories to ensure awareness of pregnancy and gestation.
Patient’s arrival (T+0 min)
Rapid assessment:
ensure airway patent,
central pulse, and absence of catastrophic bleeding before handover.
Ensure immediate and continuous uterine displacement
if gestation >20 weeks.
Structured handover from pre-hospital team to include details of gestation if available.
Immediate management and ongoing review (T+0–15 min)
Primary survey: concomitant assessment and intervention
(<C> ABCD)</C>
Team raises index of suspicion for cardiorespiratory decompensation
and pelvic fracture, and acts accordingly.
Team ensures thoracic decompression performed at appropriate level.
Assessment to include fetal heart rate and examination for obstetric complications.
Urgent request for coagulation thromboelasticity assay results and input from haematologist.
KBT and Clauss fibrinogen to be added to usual blood test requests.
Team to determine whether permissive hypotension and fixed-ratio blood product replacement are appropriate strategies relative to gestation and likely source of bleeding.
ardiopulmonary resuscitation If gestation >20 weeks, ensure manual uterine displacement and prepare for resuscitative hysterotomy within 4 min of cardiorespiratory arrest.
Situational update (T+15 min)
CT vs DCS
Appreciation that single trauma CT carries minimal risk to fetus and is entirely appropriate where indicated.
DCS may require delivery of the fetus and mandates obstetric presence.
Maternal changes
Airway
Airway
↑ Tissue vascularity and oedema
↑ Breast size and neck adiposity
↑ Intra-gastric pressure
↓ Oesophageal sphincter tone
Difficult laryngoscopy and intubation
High risk of regurgitation
Airway bleeding more likely
Difficult FONA
Difficult Airway Society guidelines.16 Early rapid sequence induction. 30° head up. Remove neck collar and provide manual in-line stabilisation.
Avoidance of nasal or blind airway interventions.
Longitudinal incision during FONA may help identify an impalpable cricothyroid membrane.
Maternal changes
Breathing
Breathing ↓ FRC (30%)
↑ Oxygen consumption (60%)
↑ Minute ventilation (50%)
↓ Arterial CO2 tensions (4kPa)
Diaphragm raised 4cm
Precipitous hypoxaemia may develop as a result of respiratory compromise or apnoea. High normal PaCO2 represents hypoventilation.
Iatrogenic diaphragmatic / visceral injury.
Thoracic trauma risks abdominal organ injury.
Liberal O2 supplementation. 30° head up improves FRC.
Pre/apnoeic oxygenation techniques before intubation.
Aim PaCO2 of 4.0kPa if mechanically ventilated.
Place thoracostomy tubes 1-2 spaces higher. High index of suspicion. CT imaging.
Circulation, catastrophic haemorrhage, and cardiac arrest
Aortocaval compression: ↓Preload, ↑afterload
↓Supine cardiac output (30%)
↓Supine uteroplacental perfusion
High cardiac reserve:
↓ Systemic vascular resistance
↑ Cardiac output
↑ Blood volume (40%)
Loss of uterine autoregulation
Haematological changes:
Hypercoagulability
Physiological anaemia
Physiological thrombocytopaenia
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Once fundal height reaches umbilicus aortocaval compression becomes significant and reduces cardiac output when supine.
Blood loss of 1.5L or more (at term) may occur before signs of hypovolaemia develop at which point there is an increased risk of cardiac arrest. Dilatation of uterine and pelvic vessels – potentially catastrophic bleeding after injury.
Uteroplacental perfusion relies upon maternal mean arterial pressure.
Altered interpretation of laboratory blood tests and consumption of clotting factors depending on source of haemorrhage and gestation.
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Continuous uterine displacement: manual preferred over tilt as it maintains spinal alignment and allows for effective cardiopulmonary resuscitation. Resuscitative hysterotomy within 4 minutes of cardiac arrest.
High index of suspicion; early arterial line; fetal assessment to provide information regarding maternal volume status and obstetric haemorrhage; improvised pelvic binder may be necessary; damage control may not be possible without emptying uterus.
Consider appropriateness of restrictive fluid replacement strategy. Avoid vasopressor use.
Early haematology input; frequent point-of-care and coagulation tests; individualised clotting factor and fibrinogen replacement strategy; aim fibrinogen >2gL-1; activated partial thromboplastin time and prothrombin time ratios <1.5; platelets >100 x 109L-1.
Changes
Disability
Exposure + Environment
Disability (neurological)
↑ Neck adiposity
Impossible placement of cervical collar.
Continuous manual in-line stabilisation.
Exposure and environment
Uteroplacental haemorrhage
Concealed haemorrhage may be revealed by vaginal blood loss.
Ensure assessment for per vaginal blood loss during primary survey.
Changes
Disability
Exposure + Environment
Disability (neurological)
↑ Neck adiposity
Impossible placement of cervical collar.
Continuous manual in-line stabilisation.
Exposure and environment
Uteroplacental haemorrhage
Concealed haemorrhage may be revealed by vaginal blood loss.
Ensure assessment for per vaginal blood loss during primary survey.
Imaging
A single trauma series CT scan is not thought to increase the risk of fetal developmental problems (miscarriage, prematurity, teratogenesis, growth retardation and neurological conditions).7,22 However, radiation effects are cumulative, and efforts must be made to minimise unnecessary or repeated exposure. Early input from radiology colleagues is therefore recommended. I.V. iodinated and gadolinium-based contrast agents appear to be safe in pregnancy and are essential to identify areas of internal haemorrhage.23
Kids eye surgery key pts
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Ophthalmic conditions requiring surgery in children are common.
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Anaesthetic techniques should minimise increases in intraocular pressure, particularly in glaucoma surgery and traumatic eye injuries.
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Ophthalmic surgery can elicit the oculocardiac reflex and is associated with a high incidence of postoperative nausea and vomiting.
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With improved neonatal care, there are increasing numbers of premature and ex-premature infants that require ophthalmic surgery.
Craniosynostosis
(Apert/Pfeiffer/Crouzon syndromes)
Cataracts/strabismus/glaucoma Difficult airway
facemask ventilation difficult because of midface hypoplasia
Craniofacial abnormalities
(Treacher Collins/Goldenhar syndromes)
Cataracts/strabismus/glaucoma
Difficult airway
Mucopolysaccharidoses
(Hunter’s/Hurler’s syndromes) Cataracts/retinitis pigmentosa Difficult airway
especially intubation
Cardiac lesions
cardiomyopathy
intubation difficult because of micrognathia and facial asymmetry
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Chromosomal
(Trisomy 21/Edward’s syndrome) Cataracts/strabismus/glaucoma Difficult airway
Difficult facemask ventilation, intubation, or both
Cardiac lesions
AVSD, tetralogy of Fallot
Cervical instability
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Neurocutaneous syndromes
(Sturge Weber/Neurofibromatosis/Von Hippel–Lindau syndromes) Retinal vascular disorders, glaucoma Seizures
Cardiac lesions
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Marfan’s syndrome Lens dislocation Cardiac lesions
aortic root dilation, aortic valve regurgitation, mitral valve prolapse
Homocystinuria
Lens dislocation
Glucose control
Thromboembolic events
Oculocardiac reflex
Oculocardiac reflex
Ophthalmic surgery can evoke a strong OCR
resulting in a profound bradycardia.
Very rarely this may result in sinus arrest.
This is caused by pressure on the globe or traction of the extraocular muscles and is mediated through
trigeminal afferent and vagal efferent pathways.
It is more common in children because of their higher vagal tone.
This reflex is well recognised as a complication of strabismus surgery but may also occur during enucleation, vitreoretinal surgery and orbital surgery.
The surgeon should be asked to release traction on the eye muscles or pressure on the globe in the first instance.
A pre-filled syringe of atropine 20 μg kg−1 or glycopyrrolate 10 μg kg−1 should be readily available and administered if the bradycardia does not promptly recover
Postoperative nausea and vomiting
Postoperative nausea and vomiting
Ophthalmic surgery is emetogenic,
and the risk of PONV increases above the age of 3.
Strabismus surgery is particularly high risk.
The Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI) updated its guidance on prevention of PONV in 2016.4
Recommendations include dual therapy in the operating theatre with ondansetron and dexamethasone;
and rescue therapy with a different agent, such as droperidol, in the postoperative recovery room.
Dexamethasone is effective at preventing late (>6 h) PONV,
but is contraindicated in patients with a haematological malignancy as it can cause tumour lysis syndrome.
Droperidol is contraindicated in patients known to have a long QT interval.
Cyclizine is no longer recommended.4
Analgesia and regional ophthalmic blocks
Analgesia and regional ophthalmic blocks
Most ophthalmic surgery is not overly painful,
and simple analgesia including paracetamol,
NSAIDs and topical anaesthesia is usually sufficient.
Vitreoretinal surgery,
evisceration of the orbital contents,
open dacryocystorhinostomy (DCR),
and cryotherapy can be very painful and generally require supplemental opioids.
Strabismus surgery can also be more painful than generally recognised.
Ophthalmic regional blocks offer several advantages in adults including akinesis of the globe providing a still operating field, and a beneficial reduction in the OCR.5
The improved perioperative analgesia minimises the need for an opioid with a reduction in PONV.
There are three main types of blocks:
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Intraconal (retrobulbar)
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Extraconal (peribulbar)
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Sub-Tenon’s block
