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Pediatric bladder volume assessments

July 21, 2021
  • 00:02In this video tutorial,
  • 00:04we will review the necessary
  • 00:07steps to obtain accurate bladder
  • 00:09volume measurements for patients in
  • 00:12the pediatric Ed, and we will review
  • 00:15some cases where this pokus
  • 00:18application can be used to help
  • 00:20streamline your patient care.
  • 00:25Indications to perform a diagnostic
  • 00:28bladder scan include the following one.
  • 00:31Prior to urine catheterization
  • 00:33to minimize risk of a dry Cath 2.
  • 00:37Patients with suspected ovarian torsion
  • 00:41before radiology performed ultrasound.
  • 00:43Tadim adequacy of bladder filling.
  • 00:47Three patients with urine retention.
  • 00:50Four patients were reported
  • 00:53oliguria or anuria,
  • 00:555 patients with incomplete bladder emptying.
  • 00:596 patients who require suprapubic
  • 01:02bladder aspiration procedure.
  • 01:08Diagnostic bladder scans are
  • 01:10to be performed with a low
  • 01:13frequency curvilinear transducer.
  • 01:18To maximize patient comfort and
  • 01:20improve the quality of your study,
  • 01:23hold the transducer like a
  • 01:24pen with an incorrect grip.
  • 01:26Unnecessary pressure is often applied to
  • 01:29the patient skin with a correct grip.
  • 01:31The ulnar side of your hand will be
  • 01:34directly touching the patient's body.
  • 01:36This will allow you to maneuver the
  • 01:39probe as necessary and allow for a more
  • 01:42comfortable experience for your patient.
  • 01:47Please feel free to wear gloves
  • 01:50during your ultrasound scan.
  • 01:51Many patients will feel more relaxed
  • 01:53and the routine use of gloves
  • 01:55will also decrease the risk of
  • 01:57infectious disease transmission.
  • 02:02Before we dive into the image
  • 02:04acquisition steps for your bladder scan,
  • 02:06let's review a couple of
  • 02:08important housekeeping items.
  • 02:09Firstly, the epic order to choose from
  • 02:12the quick list menu is Ed diagnostic
  • 02:15flatter volume eval using this correct
  • 02:17order will ensure that your image is
  • 02:20captured will be transferred to EPIC,
  • 02:22and a report of your interpretation
  • 02:24will be generated.
  • 02:26Secondly, it is important to fill out Q
  • 02:29path immediately after your bladder scan.
  • 02:31Is completed and attending signature
  • 02:33will be required to push both the images
  • 02:37and report over to the medical record.
  • 02:42First you will scan through the bladder
  • 02:45and transverse orientation with the
  • 02:46indicator towards the patient right?
  • 02:48Make sure you're all the way down
  • 02:50to the pubic synthesis in order to
  • 02:53visualize the bladder and slowly
  • 02:54fan the probe all the way through.
  • 02:59Next you will turn the probe
  • 03:01clockwise 90 degrees so that the
  • 03:03indicator is pointing towards the
  • 03:05patients head and this view you
  • 03:07will see the bladder in long axis.
  • 03:09Again, you want to slowly fan
  • 03:11the probe all the way through and
  • 03:13keep an eye out for any abnormal
  • 03:15lesions or masses that may
  • 03:17be present behind the bladder.
  • 03:21In the next step,
  • 03:23we will review how to actually obtain
  • 03:25your bladder volume measurements.
  • 03:27As long as you're using a
  • 03:29curvilinear probe utilizing the
  • 03:31abdominal or pelvic exam mode,
  • 03:32you'll be able to pull up
  • 03:35the right calculator.
  • 03:36Let's look at the buttons that
  • 03:38are squared off in pink boxes.
  • 03:40You will once again return to
  • 03:43transverse orientation and find
  • 03:44the bladder where you see it at
  • 03:47its biggest size and hit freeze.
  • 03:49Here you will enter.
  • 03:50The calc button all the way on the left.
  • 03:53This will allow you to enter
  • 03:55your first measurement,
  • 03:56which will be the height when
  • 03:58you push the measure button,
  • 04:00a caliper will appear on your screen monitor.
  • 04:03You can use the trackpad
  • 04:05to move the caliper from
  • 04:06the top of the bladder to the bottom
  • 04:09of the platter. You can then repeat these
  • 04:11steps still in transverse orientation to
  • 04:14obtain a width measurement and you
  • 04:16can now save a still image of your
  • 04:19transverse measurements by hitting the.
  • 04:20Acquire button to obtain your
  • 04:23bladder length measurement.
  • 04:24You'll have to unfreeze the screen
  • 04:26by hitting the 2D mode button.
  • 04:29That is an orange
  • 04:31color above the trackpad. You once
  • 04:33again hit the CAP button and the
  • 04:36machine will remember your prior
  • 04:39two measurements and allow you to
  • 04:41now obtain a third measurement.
  • 04:43Placed the caliper on the Trigone area of
  • 04:47the bladder and obtain the
  • 04:49longest distance seen.
  • 04:51Towards the bottom part of the
  • 04:53bladder. Once you obtain this
  • 04:56final measurement, the. Ultrasound
  • 04:58machine will automatically
  • 05:00generate the bladder volume using
  • 05:02a pre designated formula that has
  • 05:04been programmed into the system.
  • 05:09Your final step will be to interpret
  • 05:11your appointed Carol to sound
  • 05:13findings related to the platter.
  • 05:14Depending on why you're doing
  • 05:16this study in the 1st place,
  • 05:18you will make an assessment of
  • 05:20whether there is sufficient or
  • 05:21insufficient amount of urine for
  • 05:23a catheterization procedure and
  • 05:24likewise sufficient or insufficient
  • 05:25amount of urine for radiology.
  • 05:27Performed
  • 05:27ultrasound to assess for
  • 05:29ovarian pathology, and you
  • 05:30will also be asked to provide a general
  • 05:32assessment of the amount of urine in
  • 05:35the bladder which you will correlate
  • 05:36clinically and apply those volume
  • 05:38measurements to expected bladder capacity.
  • 05:40And established norms for postvoid residuals.
  • 05:46The good news is that you will not
  • 05:48be expected to memorize anything.
  • 05:51All of the necessary formulas that
  • 05:53you may need will be embedded into
  • 05:55the queue path worksheet created for
  • 05:57bladder volume evaluations in RED.
  • 06:00This will help you with your
  • 06:02interpretations as you fill out the
  • 06:04worksheet findings in real time.
  • 06:09So let's look at some practice cases.
  • 06:16Case one, a 2 year old girl with
  • 06:20Linux gesto seizure disorder.
  • 06:21G2 dependance neurogenic bladder and
  • 06:24global developmental delay presents
  • 06:26with unexplained tachycardia and
  • 06:28increase in seizure frequency.
  • 06:30As part of her work up,
  • 06:32urine testing is ordered.
  • 06:33Mom opts to do a urine catheterization
  • 06:36herself as she is routinely dusis at home,
  • 06:39but she was unsuccessful and reports
  • 06:41was unable to obtain any urine.
  • 06:44She is very concerned that her daughter
  • 06:46is dehydrated and the nursing staff
  • 06:48does not feel comfortable performing a
  • 06:51repeat catheterization at this time.
  • 06:55You first recorded the bladder
  • 06:57in transverse orientation,
  • 06:58and although it appears less
  • 06:59round than you usually expect,
  • 07:01there seems to be a fair
  • 07:04amount of urine present.
  • 07:06You then rotate the probe 90
  • 07:08degrees and assess the letter in
  • 07:10longitudinal orientation where
  • 07:11once again the bladder is seen to
  • 07:14be filled with plenty of urine.
  • 07:19You go back to transverse
  • 07:21orientation and freeze the screen.
  • 07:23Obtain a height measurement
  • 07:25from top to bottom. Obtain
  • 07:27a width measurement from left to right.
  • 07:31Save that image. He then get the length
  • 07:35of the bladder in longitudinal orientation,
  • 07:39placing the calipers across
  • 07:41the longest possible distance.
  • 07:43The ultrasound machine automatically
  • 07:46calculates the volume estimate
  • 07:48of 82 CCS.
  • 07:53You review these findings with mum
  • 07:56and the nursing staff and feel that a
  • 07:59repeat attempt at urine catheterization
  • 08:02would be reasonable to perform.
  • 08:07Repeat catheterization is successful
  • 08:09and ultimately diagnostic for a
  • 08:12urinary tract infection with greater
  • 08:14than 100,000 colony forming units
  • 08:17of Enterococcus arena over sound
  • 08:19performed by diagnostic radiology.
  • 08:21Revealed debris within the right
  • 08:24erator which was causing obstruction
  • 08:27and hydroureter oh nephro sis,
  • 08:29which was managed by the
  • 08:31inpatient urology service.
  • 08:35So as it turns out, it does not
  • 08:38take much urine at all to predict
  • 08:41successful catheterization and patient
  • 08:43under two years of age without pocus.
  • 08:46To visualize splatter contents,
  • 08:48the rate of successful urine catheterization
  • 08:51in this age group was published
  • 08:53to be 72% during the observation.
  • 08:55ULL phase of a study published
  • 08:58by Chen at all in 2005.
  • 09:00However, when the investigators applied Pocus
  • 09:02to determine whether there was at least.
  • 09:05Two CC's of urine present in the bladder.
  • 09:09The rate of successful catheterization
  • 09:11when done by nursing staff was
  • 09:15reported to be as high as 96%.
  • 09:17Case 2 highlights the point of care
  • 09:20ultrasound role in ovarian torsion.
  • 09:22To expedite confirmatory testing,
  • 09:24here we have an 18 year old female who
  • 09:28presents with sudden onset of intense
  • 09:30right lower quadrant pain and nausha.
  • 09:33She reports no fever or he materia
  • 09:36denies the possibility of pregnancy
  • 09:39and has never had a pelvic exam.
  • 09:42For you,
  • 09:42she's very tearful and uncomfortable
  • 09:45and is tender to touch to the
  • 09:47right lower quadrant area,
  • 09:49you need to prioritize getting a
  • 09:52urine sample with a transabdominal
  • 09:54ultrasound to assess.
  • 09:55For ovarian torsion,
  • 09:56you record her bladder and transfers
  • 09:59orientation and notes nicely.
  • 10:00Fluid filled structure with
  • 10:02posterior acoustic enhancement.
  • 10:05Upon interrogation and longitudinal access,
  • 10:08you again see a nicely filled bladder
  • 10:10with a normal appearing uterus behind it.
  • 10:16He obtain your measurements and transverse.
  • 10:19The bladder height is about 7.3 centimeters.
  • 10:22The bladder width is about 9.7 centimeters.
  • 10:26And in longitudinal, your bladder
  • 10:28length is about 8.5 centimeters,
  • 10:31which gives you a total bladder
  • 10:33volume of about 314 CCS.
  • 10:35This is incredibly useful information,
  • 10:38as you would expect bladder capacity
  • 10:40and an adult to be about 500 CC's.
  • 10:46You determined she should be ready for
  • 10:49radiology ultrasound without delay,
  • 10:50but you also have a bonus finding on
  • 10:53your bedside scan when you gently angle
  • 10:56her probe towards her right side using
  • 10:59her bladder as an acoustic window.
  • 11:02You actually can't see her ovary on the
  • 11:05right, it appears morphologically normal,
  • 11:07and its size, shape,
  • 11:09and appearance as small follicular
  • 11:11structures within these findings make it
  • 11:13incredibly unlikely that your patient.
  • 11:15Has acute right sided ovarian torsion.
  • 11:21On the flip side, you may have come
  • 11:23across a case where something just
  • 11:26doesn't look quite right deep in the
  • 11:29pelvis in this patient who there were
  • 11:32also some concerns for ovarian torsion,
  • 11:34you can see a large ovoid lesion with
  • 11:37some follicular architecture which
  • 11:39is present behind the uterus and
  • 11:41pushing up on the uterine fundus.
  • 11:43The bladder here is decompressed,
  • 11:45but even though diagnostics for
  • 11:48ovarian torsion by ultrasound are
  • 11:50best left for our radiology experts.
  • 11:52To confirm any abnormal screening findings
  • 11:55such as this one should heighten the
  • 11:57level of urgency and should also help
  • 12:00expedite the time it takes to get your
  • 12:03patient to her definitive imaging study.
  • 12:05Now back to the case of the patient
  • 12:08with acute right lower quadrant pain.
  • 12:11Your pocus helped determine the
  • 12:13suitability of getting her over
  • 12:15to radiology to have their formal
  • 12:17diagnostic testing done at radiology.
  • 12:19A normal right sided ovary was
  • 12:22again it visualized.
  • 12:24However, she had findings
  • 12:26compatible with acute appendicitis.
  • 12:27Luckily,
  • 12:28you had already made the right call
  • 12:31to obtain lab intravenous access,
  • 12:33made her NPO,
  • 12:35and started normal saline bolus.
  • 12:39Case 3 is a post
  • 12:41void residual bladder volume measurement.
  • 12:43In this case a 10 year old circumcised
  • 12:45male presents with mild idiopathic
  • 12:47swelling to his penis and had an
  • 12:49otherwise normal genito urinary exam.
  • 12:51On review of symptoms, he
  • 12:52says that he wakes up to go to the
  • 12:55bathroom several times at night and
  • 12:57for over a year the teachers had
  • 13:00reported that he goes to the bathroom
  • 13:02several times a day while he's
  • 13:04at school. Your plan is to do a dose of
  • 13:07Benadryl for the. Mild swelling
  • 13:09and obtained a year analysis
  • 13:11to screen for potential causes
  • 13:12of these symptoms. However,
  • 13:14he is only able to avoid a
  • 13:16small amount with great difficulty.
  • 13:23He record his bladder and
  • 13:24transfers orientation and
  • 13:25slowly fan all the way through.
  • 13:33He then record his bladder
  • 13:35and longitudinal orientation.
  • 13:38When you obtain your
  • 13:40measurements, his bladder
  • 13:42volume is a 323CC's calculated,
  • 13:45which is an abnormal postvoid
  • 13:47residual which signifies
  • 13:49incomplete bladder emptying.
  • 13:54Based on your focus
  • 13:55results, you have the patient go to
  • 13:58radiology to have a renal ultrasound done
  • 14:01where hydronephrosis has
  • 14:02not found but incomplete.
  • 14:04Bladder emptying again is confirmed,
  • 14:06your urinalysis did not show any
  • 14:08signs of glucose urea or signs of
  • 14:11infection. Putting everything together,
  • 14:12you recommend a trial of miralax
  • 14:15with an outpatient referral
  • 14:16to urology. Should symptoms
  • 14:18persist, you also review the
  • 14:20potential for you and retention
  • 14:22secondary to anti histamine
  • 14:24medications like Benadryl.
  • 14:27A potential pitfall when
  • 14:28scanning for the bladder is at
  • 14:31your probe is actually not low enough.
  • 14:33Note these split screens of the
  • 14:35same patient during a scan done
  • 14:37around the same time on the top row,
  • 14:40the curvilinear probe is placed in
  • 14:42the suprapubic area with the probe
  • 14:44slightly angled towards the umbilicus.
  • 14:46This results in only about to be
  • 14:49present and seen on the monitor on
  • 14:51the 2nd row of images the curvilinear
  • 14:53probe has been placed over the pubic
  • 14:56synthesis and slightly angled.
  • 14:57In a caudad direction.
  • 14:59At this point,
  • 15:00the bladder can be seen to come
  • 15:02into view on the screen.
  • 15:06The other important pitfall to
  • 15:08be aware of is that large cystic
  • 15:10structures in the pelvis may
  • 15:12mimic the appearance of a bladder.
  • 15:14I would pay particular careful attention
  • 15:17and patients who present with urine
  • 15:19retention as a chief complaint.
  • 15:21Here we see a 10 year old girl who
  • 15:23complained of new onset Constipation
  • 15:25and a sensation of incomplete
  • 15:27bladder emptying ultrasound images
  • 15:29by point of care and radiology.
  • 15:31I thought the cystic structure being
  • 15:33measured was her bladder, however.
  • 15:35Her bladder was completely
  • 15:37decompressed and empty during
  • 15:39the time of the ultrasound scans.
  • 15:41What was thought to have been a
  • 15:44ureteral seal was actually part
  • 15:46of a mature cystic teratoma which
  • 15:49was diagnosed by pelvic MRI at
  • 15:52the time of the MRI study.
  • 15:54The bladder could be better visualized
  • 15:56and the Mass Effect causing bladder
  • 15:59compression was more clearly seen.
  • 16:04In summary, we have reviewed some
  • 16:06cases where POCUS was used as
  • 16:08a tool to expedite patient care
  • 16:11and help to guide procedures.
  • 16:13Bladder scan by pocus for the
  • 16:16assessment and interpretation of
  • 16:17body measurements is an important
  • 16:19skill for Penn physicians to learn.
  • 16:22As always, with focus.
  • 16:23If you see something unexpected
  • 16:25that doesn't fall into the typical
  • 16:27pattern recognition appearance,
  • 16:29please do not hesitate