SCOB - TriHealth · 2019. 11. 19. · Critical Care Obstetrics Background / Rationale Maternal mortality rate in the U.S. is rising Sonography can augment the clinical response to

Critical Care Obstetrics

SCOBSonography in Critical Care

OBstetrics


Learning Objectives

Background / Rationale

Cardiac Output Assessment

Pulmonary Assessment

Volume Assessment

FAST Scan

Systemic Vascular Resistance

Assessment


Background / Rationale

Maternal mortality rate in the U.S. is rising

Sonography can augment the clinical response to

nearly ALL of the leading causes

27.1

14

10.7

7.9

3.2

0 5 10 15 20 25 30

HEMORRHAGE

HYPERTENSIVE DISORDERS

SEPSIS

ABORTION

EMBOLISM

Percentage


Point-of-Care Ultrasound

FAST Scan

RUSH Protocol

Standard OB imaging

Fetal echocardiography

Novel sonographic techniques


Purpose

Application of Point-of-Care Sonographic

techniques to gain a deeper understanding of

physiologic changes among pregnant women

experiencing critical illness

Assess the utility of these adjunctive sonographic

techniques to augment clinical decision-making in

critical care scenarios


Cardiac Output

Assessment


Calculating End-Point Septal Separation (EPSS) of

the medial mitral leaflet using M-mode sonography

Parasternal Long Axis View

Place M-mode gate vertically to capture full medial mitral leaflet

and ventricular septum during a full cardiac cycle

LVEF = 75.5 -2.5(EPSS in mm)

LV

RV

LA

Ao

Mitral

ValveD Ao

Aortic

Valve

Ventricular

Septum


Calculating End-Point Septal Separation (EPSS) of the medial

mitral leaflet using M-mode sonography

Parasternal Long Axis View

Place M-mode gate vertically to capture full medial mitral leaflet and

ventricular septum during a full cardiac cycle


Biphasic M-Mode Wave

• E-wave (Early Diastolic

Excursion

• A-wave (Atrial Kick)


Calculating End-Point Septal Separation (EPSS) of the medial mitral leaflet using M-mode sonography Parasternal Long Axis View

Place M-mode gate vertically to capture full medial mitral leaflet and ventricular septum during a full cardiac cycle



Cardiac output: (heart rate x stroke volume)

In parasternal long axis view for LVOT measurement, measure

just above the aortic valve during systole

To measure VTI, use pulsed-wave Doppler in the apical 4-

chamber (just beneath left nipple / breast) view with the gate just

below the aortic valve

LVOT (mm)



In parasternal long axis view for LVOT measurement, measure

just above the aortic valve during systole

To measure VTI, use pulsed-wave Doppler in the apical 4-

chamber (just beneath left nipple / breast) view with the gate just

below the aortic valve

LV

RV

LVOT



Stroke volume = LVOT area x LVOT VTI

SV = π x [(LVOT diameter)/2]2 x VTI

VTI = velocity time integral manually traced using pulsed-wave

Doppler sampling of the LVOT

CO = SV x HR


SV = 3.14 x [2.2 cm / 2]2 x 17.9 cm

SV = 67.4 cm

HR = 80 bpm

CO = 5,386 cm/min or 5.4 L/min





VTI = velocity time integral manually traced using pulsed-wave

Doppler sampling of the LVOT





VTI = velocity time integral manually traced using pulsed-wave Doppler sampling of the LVOT


Pulmonary

Assessment


Patient Positioning

Sonographer

scans from

patient right

Patient is

supine with

slight leftward

decubitus

position


Pneumothorax

Bedside sonography is more reliable than AP plain chest X-ray for pneumothorax detection

95-100% sensitivity & 91% specificity for detecting pneumothorax

Lyon M, Walton P, Bhalia V, et al. Ultrasound detection of the sliding

lung sign by prehospital critical care providers. Am J Emerg Med.

2012;30(3):485-88.

Lichtenstein DA, Meziere G, Lascois N, et al. Ultrasound diagnosis of

occult pneumothorax. Crit Care Med 2005;33(6)1231-38.


Pneumothorax

Place transducer on

anterior chest at the 2nd

or 3rd intercostal space

Air will rise to most

superior / anterior

portion of the chest


Pneumothorax

Pneumothorax is ruled-out

by any of the following

Sliding-lung sign

B-lines or lung rockets

Lung pulse

It’s ruled-in by identifying

gas / air within the pleural

space

Lichtenstein DA, Meziere G, Lascois N, et al. Ultrasound diagnosis of

occult pneumothorax. Crit Care Med 2005;33(6)1231-38.


Pneumothorax

Sliding-Lung Sign

Identify two ribs and the

bright pleural line beneath

To-and-fro sliding of the

pleural line

Synchronized with

respirations

No pneumothorax under

the US transducer

Rib RibPleural Line


Pneumothorax

Sliding-Lung Sign

Identify two ribs and the

bright pleural line beneath

To-and-fro sliding of the

pleural line

Synchronized with

respirations

No pneumothorax under

the US transducer


Pneumothorax

Lack of Sliding-Lung

Sign

Pneumothorax

Emphysema

Esophageal or contralateral

main-stem bronchus

intubation


Pulmonary Edema

Bedside sonography is

a reliable method for

accurate detection of

pulmonary edema

Easily repeated and

can monitor resolution

from diuretics

Noble VE et al. Ultrasound assessment for extravascular lung water

in patients undergoing hemodialysis. Time course for resolution.

Chest 2009; 135:1433-39.


Pulmonary Edema

Place transducer between

ribs (rib inter-space) at

most dependent portion of

lungs (posterior axillary

line just above diaphragm

bilaterally)

Fluid will fall to most

inferior / posterior portion

of the chest


Pulmonary Edema

Pulmonary Edema is

identified by B-Lines or

Lung Rockets

B-lines – hyperechoic

vertical laser-like beam

reaching far field of screen &

move in concert with lung

motion

Lung rockets – 3 or more B-

lines noted in inter-rib

spaces


Pulmonary Edema

Pulmonary Edema is

identified by B-Lines or

Lung Rockets

B-lines – hyperechoic

vertical laser-like beam

reaching far field of screen &

move in concert with lung

motion

Lung rockets – 3 or more B-

lines noted in inter-rib

spaces


Pleural Effusions

Place transducer between

ribs (rib inter-space) at

most dependent portion of

lungs (mid or posterior

axillary line just above

diaphragm bilaterally)

Fluid will fall to most

inferior / posterior portion

of the chest


Pleural Effusions

Plain Chest X ray

65% Sensitivity

81% Specificity

Lung Ultrasonography

97-100% Sensitivity

94-100% Specificity

Brogi E, Gargani L, Bignami E, et al. Thoracic ultrasound for pleural

effusion in the intensive care unit: a narrative review from diagnosis to

treatment. Crit Care. 2017;21:325.


Pleural Effusions

RUQ Mid-Axillary

Identify Liver,

diaphragm, and chest

wall

Dark fluid identified

above diaphragm

Lung seen moving

with respiration

Air identified within

the bronchioles as

bright


Volume Assessment


Stroke volume variation: (maximum SV – minimum SV)/mean SV

Using pulsed-wave Doppler at the left ventricular outflow tract (LVOT) over 10 seconds

Measure the peak systolic velocity of the highest wave and the smallest wave.

Measure the average of all the waves (can use the auto trace function to calculate) in the cardiac settings

LV

RV

LVOT


Stroke volume variation: (maximum SV – minimum SV)/mean SV

Using pulsed-wave Doppler at the left ventricular outflow tract (LVOT) over 10 seconds

Measure the peak systolic velocity of the highest wave and the smallest wave.

Measure the average of all the waves (can use the auto trace function to calculate) in the cardiac settings

>13% = Fluid Responsive

Zhang Z, Lu B, Sheng Z, et al. Accuracy of stroke volume

variation in predicting fluid responsiveness. J Anesth.

2011 Dec:25(6):904-16.


In sagittal plane just right of midline beneath the costal margin in the RUQ of the abdomen, identify the inferior vena cava (IVC)

Measure diameter of the IVC using M-mode or calipers at maximum diameter during inspiration and expiration at least 3 cm from diaphragm



In sagittal plane just right of midline beneath the costal margin in the RUQ of the abdomen, identify the inferior vena cava (IVC)

Measure diameter of the IVC using M-mode or calipers at maximum diameter during inspiration and expiration


FAST SCAN


Focused Abdominal Scan in Trauma

Blunt or penetrating

trauma to the

abdomen

Abdominal pain or

hemodynamic

instability in

pregnancy

Unexplained

hypotension


RUQ View

Morrison’s pouch –

the most dependent

portion of the

abdomen

Look for interface

between right

kidney and liver

Look above liver

beneath diaphragm


RUQ View

Morrison’s pouch –

the most dependent

portion of the

abdomen

Look for interface

between right

kidney and liver

Look above liver

beneath diaphragm


RUQ View

Morrison’s pouch –the most dependent portion of the abdomen

Look for interface between right kidney and liver

Look above liver beneath diaphragm

FREE FLUID BETWEEN R KIDNEY

AND LIVER


LUQ View

Interface of spleen

and left kidney

Must appear to be

in contact with each

other

Caution for fluid in

stomach which can

be misleading


LUQ View

Interface of spleen

and left kidney

Must appear to be

in contact with each

other

Caution for fluid in

stomach which can

be misleading


LUQ View

Interface of spleen and left kidney

Must appear to be in contact with each other

Caution for fluid in stomach which can be misleading

FREE FLUID BETWEEN L KIDNEY

AND SPLEEN


LUQ View


Supra-Pubic View

Midline sagittal just

superior to the

pubic symphysis

Best if bladder is full

Fan side-to-side

looking for anechoic

“wedges”


Supra-Pubic View

Midline sagittal just superior to the pubic symphysis

Best if bladder is full

Fan side-to-side looking for anechoic “wedges”

FREE FLUID ADJACENT TO THE

BLADDER


Systemic Vascular

Resistance

Assessment


Systemic vascular resistance (Both methods of calculation)

Resistance index using pulsed-wave Doppler of the dorsal branch of the radial artery

Hold transducer in sagittal plane at the base of the thumb

Pulsed-wave Doppler assessment of Resistance Index [(velocity during systole – velocity during diastole) / velocity during systole]

Also can calculate systemic vascular resistance separately to correlate

SVR = Mean Arterial Pressure (MAP) x 80/Cardiac output
















Parameter

Finding Therapeutic Approach

Volume IVC Maximum Diameter

IVC Caval Index

Stroke Volume Variation

Low IVC diameter < 1.3 cm IVC caval index > 50%

SVV > 13%

IV Fluid Bolus (500 ml LR over 10 min) + Labetalol

• Low Volume

• High Cardiac Output

• Normal or Low SVR

• Predominantly Systolic BP w/normal PP

Normal IVC diameter 1.3 – 2 cm IVC caval index 25-50%

SVV 5-13%

IV Fluid Bolus (500 ml LR over 10 min) + Hydralazine

• Low Volume • Low or Normal Cardiac Output

• Normal or High SVR

• Predominantly Diastolic BP w/low or normal Pulse Pressure

High IVC diameter > 2 cm

IVC caval index < 25%

SVV < 5%

Labetalol Alone

• Normal Volume • High Cardiac Output

• Low or Normal SVR

• Predominantly Systolic BP w/normal or high

Pressure

Cardiac Output End-Point Septal Separation

for LVEF Calculation Cardiac Output = HR x SV

(SV = LVOT area x LVOT VTI)

Low LVEF < 50%

CO < 5 L/min

Nifedipine Alone

• Normal Volume

• Normal Cardiac Output • Normal SVR

• Either predominance & low or normal pulse

pressure

Normal LVEF 50-60%

CO 5-7 L/min

Hydralazine Alone

• Normal Volume • Low or Normal Cardiac Output

• High SVR

• Predominantly Diastolic w/low pulse pressure

High LVEF > 60%

CO > 7 L/min

Lasix 20 mg IV once + Labetalol

• High Volume • High Cardiac Output

• Low or Normal SVR

• Predominantly Systolic w/normal or high pulse

pressure

Systemic Vascular

Resistance Resistance Index @

Snuff Box PVR = MAP x 80/CO

Normal RI < 1

PVR < 1300

Lasix 20 mg IV once + Nifedipine • High Volume

• Normal Cardiac Output

• Normal SVR • Either predominance & low or normal pulse

pressure

High RI > 1

PVR > 1300

Lasix 20 mg IV once + Hydralazine

• High Volume

• Low Cardiac Output • High SVR

• Predominantly Diastolic w/low pulse pressure

Pulse Pressure (SBP – DBP)

Low (< 40 mmHg)

Normal (40-80 mmHg)

High (> 80 mmHg)

Predominant Type Systolic > 160 mmHg

Diastolic > 110 mmHg

Systolic

Diastolic

Documents

SCOB - TriHealth · 2019. 11. 19. · Critical Care Obstetrics Background / Rationale Maternal mortality rate in the U.S. is rising Sonography can augment the clinical response to