The day was all about the management of bariatric patients which is becoming an increasing issue with the rise of obesity rates in Australia. We were appropriately supplemented with doughnuts at morning tea and hot dogs at the lunch time BBQ.

 Case Review – Dr Geoff Healey, Staff Specialist, Sydney HEMS

Geoff kicked off with an educational case highlighting some of the difficulties in bariatric transfers.

A patient weighing over 180 kg who was initially admitted to a regional centre with an MI. The patient underwent unsuccessful cardiac stenting, was intubated and started on inotropes. The patient was transferred to a tertiary centre for consideration of CABG but found not to be suitable. The mission the group was presented with for discussion was to transfer the patient back to the referring hospital as a non urgent transfer. At time of transfer the patient was ventilating easily and still requiring inotropes.

The patient suffered a VT arrest on being lifted out of the aircraft at the destination site requiring CPR. ROSC was achieved but a further cardiac arrest occurred in the ED and resuscitation was unsuccessful.

Discussion:

• There was significant discussion around the risks of bariatric patient transfers.
• Transfers from tertiary hospitals to peripheral hospitals represent a different risk benefit compared to transfers from peripheral hospitals to tertiary care for the purposes of facilitating a meaningful intervention.
• Non acute bariatric transfers should occur in daylight and be well planned. They should be assigned to the most senior doctor available.

Learnings:

Identify the red flags present and have a predetermined “deal breaker” that would preclude transfer.

Be aware of the human factors issues that are invariably present with bariatric cases due to increased length and complexity.

Identify the risks and try to mitigate e.g. iv line failure, inadvertent extubation

Guest speaker – Dr David Barbic, University of British Columbia, Vancouver

David Barbic, a Sydney HEMS alum, was the guest speaker and presented an enlightening talk on the challenges of managing bariatric patients., via skype from Canada.

Classification and prevalence of Obesity

 Obese: BMI 30-39.9

Morbidly obese: >40

Super obese: >50

In Australia 28% of the population currently meet the criteria for obesity which represents 142,600 people in the greater Sydney area.

 Physiological challenges:

Respiratory

• Reduced compliance
• Reduced FRC
• Increased airway resistance
• Increased prevalence of OSA
• Rapid desaturation after apnoea
• Increased V:Q mismatch
• Plateau pressures typically higher
• Higher PEEP needed
• Difficult BMV

Cardiovascular

•  Increased myocardial oxygen demand
• Obesity cardiomyopathy – both diastolic and systolic failure
• Poor tolerance of fluid boluses
• Increased risk of DVT

Gastrointestinal

• Reduced lower oseophageal sphincter tone
• Increased risk of aspiration

Other challenges:

Imaging

• Bedside US challenging
• CT machines weight limited
• CXR often underexposed

Drugs

•  Increased GFR leads to more rapid drug excretion
• Volume of distribution altered for lipophilic drugs

Challenges with specific clinical scenarios

Trauma

•  Less likely to be wearing a seatbelt
• 37% increased mortality in trauma
• Higher mortality from TBI
• Higher rate of complications (e.g VAP)
• Increased length of stay and increased rate of ICU admissions

Burns

•  Higher rate of complications
• Difficult fluid resus (fluid requirement often underestimated)
• Rule of 9’s inaccurate (can use modified Lund-Bowder chart)

Recommendations

• Anticipate and plan for difficult airway (often difficult BMV rather than difficult intubation)
• Preoxygenate with CPAP/BIPAP
• Place patient in reverse trendelenburg
• Ramp the patient with 30 degrees head elevation
• Apnoeic oxygenation essential
• Roc provides a longer safe apnea time than sux due lower o2 consumption
• Give small fluid boluses
• Ventilate to ideal body weight

To hear more on this topic from David, have a listen to this excellent podcast:  https://emergencymedicinecases.com/obesity-emergency-management/

Installation and removal of the SPS (special purpose stretcher) – James Koens (Aircrewman)

James then talked us through how to install the SPS. While this is performed by the aircrewman, all staff should be familiar with the process.

Learnings:

There is a checklist available to assist with bariatric transfers -you can find it here AOC CLIN 10 – Bariatric Tfr – vrs 1-02

 Hover Mat demonstration – Stu Gourlay (Paramedic)

 Stu took us through how to transfer a patient on the hover mat.

Learnings:

Doctor will take the airway/head and the paramedic will always “catch” the patient due to the risk of overshoot

Log roll the patient onto the hover mat and then inflate using the blowing device

Leave the patient harnesses as loose as possible during inflation so that they don’t constrict the patient once the mat is inflated.

Move feet over first and then push rather than pull the patient over onto the stretcher

Simulated exercise – Dr Chris Partyka (Staff specialist, Sydney HEMS)

Chris facilitated a sim involving a 140kg male who had come off his mountainbike sustaining a fractured femur and a mild head injury. The medical crew were winched in and then had to determine the most appropriate method of retrieving the patient.

Learnings:

Weight limit for winch is 240kg. This includes the patient, the doctor, the stretcher (10kg) and any equipment.

Unaccompanied stretcher winches are not permitted

Medical team may need to wait for a road crew – be prepared for a prolonged stay on scene.

Journal Club – Dr James Moran (Retrieval Registrar, Sydney HEMS)

 Jamie presented this month journal club article which reviewed the challenges of managing a bariatric patient in ED. There is very little literature on the management of these patients in the prehospital environment and the ED experience probably provides the best surrogate. The full paper can be found here Journal Club 20:9:17.pdf