Surgeon-performed bedside ultrasound to assess volume status: a feasibility study

A systematic review of point-of-care abdominal ultrasound scans performed by general surgeons in paediatric patients

BACKGROUND/PURPOSE

Bedside point-of-care ultrasound scans are a cheap, quick and safe diagnostic tool. There is increasing evidence for the use of point-of-care surgeon-performed ultrasound scans in adults, however there are fewer studies of its use in children. This systematic review aims to provide an up-to-date summary of the evidence behind surgeon-performed ultrasound scans in paediatric surgery.

METHODS

The PubMed database was used to conduct this systematic review between the dates 1 Jan 1980 to 1 June 2020 (last search: 1 June 2020). Seven primary research studies were included in this review.

RESULTS

There is good evidence for the use of ultrasound scans in appendicitis and hypertrophic pyloric stenosis. Training times are easily achievable and transferable within a surgical department.

CONCLUSIONS

Although the use of surgeon-performed bedside ultrasound scans has been described in appendicitis and hypertrophic pyloric stenosis, more research is required to embed this into clinical practice, particularly in low volume centres such as district general hospitals. A robust training programme is also recommended to incorporate ultrasound scans into clinical practice.

Non-radiologist-performed abdominal point-of-care ultrasonography in paediatrics - a scoping review

BACKGROUND

Historically, US in the paediatric setting has mostly been the domain of radiologists. However, in the last decade, there has been an uptake of non-radiologist point-of-care US.

OBJECTIVE

To gain an overview of abdominal non-radiologist point-of-care US in paediatrics.

MATERIALS AND METHODS

We conducted a scoping review regarding the uses of abdominal non-radiologist point-of-care US, quality of examinations and training, patient perspective, financial costs and legal consequences following the use of non-radiologist point-of-care US. We conducted an advanced search of the following databases: Medline, Embase and Web of Science Conference Proceedings. We included published original research studies describing abdominal non-radiologist point-of-care US in children. We limited studies to English-language articles from Western countries.

RESULTS

We found a total of 5,092 publications and selected 106 publications for inclusion: 39 studies and 51 case reports or case series on the state-of-art of abdominal non-radiologist point-of-care US, 14 on training of non-radiologists, and 1 each on possible harms following non-radiologist point-of-care US and patient satisfaction. According to included studies, non-radiologist point-of-care US is increasingly used, but no standardised training guidelines exist. We found no studies regarding the financial consequences of non-radiologist point-of-care US.

CONCLUSION

This scoping review supports the further development of non-radiologist point-of-care US and underlines the need for consensus on who can do which examination after which level of training among US performers. More research is needed on training non-radiologists and on the costs-to-benefits of non-radiologist point-of-care US.

[Index from Diameter of Inferior Vena Cava and Abdominal Aorta of Newborns - A Relevant Method for Evaluation of Hypovolemia]

Hypovolemia is one of the important problems in sick neonates. Ultrasound is a safe, noninvasive diagnostic tool for the assessment of volume status. For that reason, the aim of the study was to determine normal values of the diameter of inferior vena cava (IVC), abdominal aorta (Ao) and the index IVC/Ao.

PATIENTS AND METHODS

97 healthy, term neonates were included in the study and investigated at first and third day of life. The diameter of IVC, Ao was measured and the index from IVC/Ao was estimated. Using statistics mean and median values of the parameters and correlations to birth weight were determined.

RESULTS

Diameter of Ao at first day was 6.1 (+/-0.6) mm and at third day 6.2 (+/-0.6) mm, of IVC at first day was 2.5 (+/-0.5) and at third day 2.61 (+/-0.5). The Index from diameters of IVC/Ao was evaluated at day 1 as 0.4 (+/-0.1) and day 3 as 0.4 (+/-0.1). We found a positive correlation to the birth weight. We identified a significant difference of the index in SGA and LGA - neonates (0.36 vs 0.47). Despite a significant reduced weight from first to third day in the neonates, we determined no influence on the diameter of IVC, Ao and the index IVC/Ao.

CONCLUSION

We determined normal values of diameter of IVC and Ao and the Index of IVC/Ao. It is our opinion, that it is possible to assess the intravascular volume using the index. The importance of the index can be underlined by the results in SGA-neonates. More research is needed to understand some points of the pathophysiology in SGA.

Venous Physiology Predicts Dehydration in the Pediatric Population

BACKGROUND

No standard dehydration monitor exists for children. This study attempts to determine the utility of Fast Fourier Transform (FFT) of a peripheral venous pressure (PVP) waveform to predict dehydration.

MATERIALS AND METHODS

PVP waveforms were collected from 18 patients. Groups were defined as resuscitated (serum chloride ≥ 100 mmol/L) and hypovolemic (serum chloride < 100 mmol/L). Data were collected on emergency department admission and after a 20 cc/kg fluid bolus. The MATLAB (MathWorks) software analyzed nonoverlapping 10-s window signals; 2.4 Hz (144 bps) was the most demonstrative frequency to compare the PVP signal power (mmHg).

RESULTS

Admission FFTs were compared between 10 (56%) resuscitated and 8 (44%) hypovolemic patients. The PVP signal power was higher in resuscitated patients (median 0.174 mmHg, IQR: 0.079-0.374 mmHg) than in hypovolemic patients (median 0.026 mmHg, IQR: 0.001-0.057 mmHg), (P < 0.001). Fourteen patients received a bolus regardless of laboratory values: 6 (43%) resuscitated and 8 (57%) hypovolemic. In resuscitated patients, the signal power did not change significantly after the fluid bolus (median 0.142 mmHg, IQR: 0.032-0.383 mmHg) (P = 0.019), whereas significantly increased signal power (median 0.0474 mmHg, IQR: 0.019-0.110 mmHg) was observed in the hypovolemic patients after a fluid bolus at 2.4 Hz (P < 0.001). The algorithm predicted dehydration for window-level analysis (sensitivity 97.95%, specificity 93.07%). The algorithm predicted dehydration for patient-level analysis (sensitivity 100%, specificity 100%).

CONCLUSIONS

FFT of PVP waveforms can predict dehydration in hypertrophic pyloric stenosis. Further work is needed to determine the utility of PVP analysis to guide fluid resuscitation status in other pediatric populations.

Review of bedside surgeon-performed ultrasound in pediatric patients

PURPOSE

Pediatric surgeon performed bedside ultrasound (PSPBUS) is a targeted examination that is diagnostic or therapeutic. The aim of this paper is to review literature involving PSPBUS.

METHODS

PSPBUS practices reviewed in this paper include central venous catheter placement, physiologic assessment (volume status and echocardiography), hypertrophic pyloric stenosis diagnosis, appendicitis diagnosis, the Focused Assessment with Sonography for Trauma (FAST), thoracic evaluation, and soft tissue infection evaluation.

RESULTS

There are no standards for the practice of PSPBUS.

CONCLUSIONS

As the role of the pediatric surgeon continues to evolve, PSPBUS will influence practice patterns, disease diagnosis, and patient management.

TYPE OF STUDY

Review Article.

LEVEL OF EVIDENCE

Level III.

Use of bedside abdominal ultrasound to confirm intestinal motility in neonates with gastroschisis: A feasibility study

BACKGROUND

Optimal timing to begin feeds in neonates with gastroschisis remains unclear. We examined if bedside abdominal ultrasound for intestinal motility is a feasible tool to detect return of bowel function in neonates with gastroschisis.

METHODS

Neonates born with uncomplicated gastroschisis who underwent closure received daily ultrasound exams. Full motility was defined as peristalsis seen in all quadrants. Average length of time between abdominal wall closure and start of enteral feeds, full ultrasound motility, and clinical characteristics was compared using Student's t-tests.

RESULTS

Seventeen patients were enrolled. No differences were found between motility on ultrasound and bowel movements, gastric residuals, or nonbilious residuals. Mean time to enteral feeds (11.82days) was significantly delayed compared to documentation of full motility on ultrasound (8.94days; p=0.012), consistent bowel movements (8.41days; p=0.006), low gastric residuals (9.47days; p<0.001), and nonbilious residuals (9.18days; p<0.001). In the single subject in which feeds were started before full motility was seen on ultrasound, feeds were subsequently discontinued because of emesis.

CONCLUSION

Bedside abdominal ultrasound provides real-time evidence regarding intestinal motility and is a feasible tool to detect return of bowel function in neonates with gastroschisis. Future studies are needed to determine if abdominal ultrasound can shorten time to start of enteral feeds.

LEVEL OF EVIDENCE

III (diagnosis: nonconsecutive study).