Incorporating personal-device-based point-of-care ultrasound into obstetric care: a validation study

The Potential of Tele-Ultrasound, Handheld and Self-Operated Ultrasound in Pregnancy Care: A Systematic Review

OBJECTIVE

To explore the use of tele-ultrasound and handheld or self-operated ultrasound in pregnancy.

METHODS

A systematic search provided 31 studies. The risk of bias for each study was assessed. Results were analyzed and presented in a narrative overview in four domains: tele-ultrasound, patient-operated ultrasound, handheld devices and low- and middle-income countries (LMIC).

RESULTS

The quality of studies was generally low or fair based on the NIH Quality Assessment Tools. Fetal tele-ultrasound services (11 studies) are feasible and especially helpful in rural areas or with increased centralization of specialist care. Three studies with patient-operated ultrasound concluded its feasibility with good-to-high experiences. The use of handheld devices in pregnancy (eight studies) showed similar ultrasound results when compared to standard devices. In LMICs, innovative use of ultrasound (nine studies) can facilitate access to obstetric care performed by trained as well as unskilled caregivers combined with remote evaluation by an expert.

CONCLUSIONS

Innovations in ultrasound in pregnancy care have shown promising results for application. Although most studies demonstrated benefits for pregnant women or care providers, high-level evidence is scarce. High-quality studies on innovations are needed to assess medical outcomes, patient and provider experiences and costs.

Evaluating the accuracy and reliability of non-piezo portable ultrasound devices in postpartum care

INTRODUCTION

The early diagnosis of hemorrhage via postpartum ultrasound is crucial to initiate therapy and, thus, prevent maternal death. In these critical situations rapid availability and simple transport of ultrasound devices is vital, paving the way for a  new generation of portable handheld ultrasound devices (PUD) consisting of transducers and tablets or smart phones. However, evidence to confirm the diagnostic accuracy of these new devices is still scarce.

METHODS

The accuracy and reliability of these new devices in relation to established standard ultrasound devices is analyses in this pilot study by comparing diagnoses and by applying statistical analysis via Bland-Altman plots, intraclass correlation coefficients (ICC), and Pearson correlation coefficients (PCC). One hundred patients of a university hospital were included in this study.

RESULTS

In all cases, the same diagnosis was made regardless of the applied ultrasound device, confirming high accuracy. There was a high correlation (PCC 0.951) and excellent agreement (ICC 0.974) in the assessment of the cavum, while the assessment of the diameters of the uterus showed only a good correlation and a good agreement. Subgroup analysis for maternal weight, mode of delivery and day after delivery was performed  CONCLUSION: The same diagnosis independent of the used devices and excellent results of the cavum assessment promote the use of PUDs in a clinical setting. The slightly lower accuracy in the measurement of the uterus may be caused by the PUD's small acoustic window, reflecting one of its weaknesses. Therefore, the patient may benefit from the short time to diagnosis and the unbound location of examination, either in the delivery room, on the ward, or at home.

Next-generation monitoring in obstetrics: Assessing the accuracy of non-piezo portable ultrasound technology

INTRODUCTION

The emergence of handheld ultrasound devices capable of connecting to cell phones or tablets heralds a significant advancement in medical technology, particularly within the field of obstetrics. These devices offer the promise of immediate bedside ultrasound examinations, potentially revolutionizing patient care by enabling fetal assessments in diverse settings.

MATERIAL AND METHODS

This prospective study aimed to validate the reliability of non-piezo, chip-based handheld ultrasound devices in clinical obstetric practice. Conducted in a university hospital obstetric ward, the study included 100 pregnant women between 17 and 41 weeks of gestation. Participants underwent ultrasound examinations using both conventional and portable point-of-care ultrasound (POCUS) devices to compare the accuracy in estimating fetal weight and other parameters, such as cardiac activity, fetal presentation, placental location, and amniotic fluid volume. The reliability and agreement between the devices were assessed using intraclass correlation coefficients, Bland-Altman plots, and Pearson correlation coefficients.

RESULTS

The results show a near-perfect agreement (0.98) and correlation (r = 0.98, p < 0.001) for estimated fetal weight and most biometry measurements between the two types of ultrasound devices, with slight deviations in head circumference and amniotic fluid index measurements. Subgroup analysis revealed variations in agreement and correlation rates with higher BMI and advanced gestational age, indicating areas for further refinement.

CONCLUSIONS

These findings affirm the high reliability of handheld ultrasound devices for basic obstetric ultrasound evaluations, supporting their integration into daily clinical practice. This technology improves the flexibility and immediacy of prenatal care, although further research is needed to optimize its application across patient populations and treatment settings.

Performance of a handheld point of care ultrasonography to assess IUD position compared to conventional transvaginal ultrasonography

OBJECTIVE

To compare the performance of the abdominal handheld point-of-care ultrasonography (POCUS) Butterfly-iQ to gold standard transvaginal ultrasonography (US) in identifying the position of intrauterine devices (IUDs) in the hands of a medical doctor specialised in ultrasonography.

METHODS

In this diagnostic accuracy study, a single operator conducted abdominal POCUS followed by conventional transvaginal US. Seventy patients utilising copper or hormonal IUDs were assessed between June 2021 and October 2022. IUDs were categorised as entirely within the uterine cavity or malpositioned. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for detecting malpositioned IUDs, with conventional US results serving as the reference standard. Concordance rate and Kappa coefficient were computed to assess the agreement between the two ultrasound modalities.

RESULTS

Among the 70 patients, 46 (65.7%) used copper IUDs, and 24 (34.3%) used hormonal IUDs. Conventional transvaginal US showed IUDs entirely within the uterine cavity in 56 (80%) patients and 14 (20%) IUDs were malpositioned. Of the 14 malpositioned IUDs seen by conventional US, POCUS identified 13 demonstrating a sensitivity of 92.9% (66.1-99.8). Of the 56 IUDs entirely within the uterine cavity shown by conventional US, only two cases were considered malpositioned by POCUS demonstrating a specificity of 96.4% (87.7-99.6). The concordance rate was 95.7%, and the Kappa value was 0.87 in differentiating between IUDs entirely within the uterine cavity and those that were malpositioned.

CONCLUSION

Abdominal POCUS using Butterfly-iQ, when administered by an imaging specialist, exhibited excellent performance in confirming IUDs entirely within the uterine cavity.

The Performance Characteristics of Handheld, Non-Piezoelectric Point-of-Care Ultrasound (POCUS) in the Emergency Department

The use of handheld point-of-care ultrasound (HH-POCUS) platforms is rapidly increasing, but the diagnostic performance of HH-POCUS in the emergency department (ED) has not been well-studied. For a period of one year, only a HH-POCUS system that uses a non-piezoelectric array (Butterfly iQ+™) was available for clinical POCUS examinations in our ED. We performed a retrospective observational study of patients who underwent cardiac, thoracic, renal, biliary, or lower extremity venous (DVT) examinations from November 2021-November 2022 and calculated performance characteristics of HH-POCUS relative to radiology imaging. A total of 381 HH-POCUS studies were evaluated. Cardiac image quality was significantly lower than lung (p = 0.002). Over half of the studies (213/381) had imaging available for comparison, and HH-POCUS identified 86.5% (32/37, (95%CI) 70.4-94.9) of prespecified emergent diagnoses, including acute cholecystitis, severely reduced left ventricular ejection fraction, pericardial effusion or tamponade, moderate or larger pleural effusion, pneumothorax, moderate or larger hydronephrosis, and DVT. For less emergent diagnoses, 84.3% (43/51, (95%CI) 70.9-92.5) were identified. Overall, HH-POCUS using a non-piezoelectric array showed modest real-world performance in the ED for cardiac, thoracic, renal, biliary, and DVT examinations. HH-POCUS may be inadequate to rule out some common ED diagnoses, but had good specificity for certain conditions such as pericardial effusion.

Impact of point-of-care ultrasound and routine third trimester ultrasound on undiagnosed breech presentation and perinatal outcomes: An observational multicentre cohort study

BACKGROUND

Accurate knowledge of fetal presentation at term is vital for optimal antenatal and intrapartum care. The primary objective was to compare the impact of routine third trimester ultrasound or point-of-care ultrasound (POCUS) with standard antenatal care, on the incidence of overall and proportion of all term breech presentations that were undiagnosed at term, and on the related adverse perinatal outcomes.

METHODS AND FINDINGS

This was a retrospective multicentre cohort study where we included data from St. George's (SGH) and Norfolk and Norwich University Hospitals (NNUH). Pregnancies were grouped according to whether they received routine third trimester scan (SGH) or POCUS (NNUH). Women with multiple pregnancy, preterm birth prior to 37 weeks, congenital abnormality, and those undergoing planned cesarean section for breech presentation were excluded. Undiagnosed breech presentation was defined as follows: (a) women presenting in labour or with ruptured membranes at term subsequently discovered to have a breech presentation; and (b) women attending for induction of labour at term found to have a breech presentation before induction. The primary outcome was the proportion of all term breech presentations that were undiagnosed. The secondary outcomes included mode of birth, gestational age at birth, birth weight, incidence of emergency cesarean section, and the following neonatal adverse outcomes: Apgar score <7 at 5 minutes, unexpected neonatal unit (NNU) admission, hypoxic ischemic encephalopathy (HIE), and perinatal mortality (including stillbirths and early neonatal deaths). We employed a Bayesian approach using informative priors from a previous similar study; updating their estimates (prior) with our own data (likelihood). The association of undiagnosed breech presentation at birth with adverse perinatal outcomes was analyzed with Bayesian log-binomial regression models. All analyses were conducted using R for Statistical Software (v.4.2.0). Before and after the implementation of routine third trimester scan or POCUS, there were 16,777 and 7,351 births in SGH and 5,119 and 4,575 in NNUH, respectively. The rate of breech presentation in labour was consistent across all groups (3% to 4%). In the SGH cohort, the percentage of all term breech presentations that were undiagnosed was 14.2% (82/578) before (years 2016 to 2020) and 2.8% (7/251) after (year 2020 to 2021) the implementation of universal screening (p < 0.001). Similarly, in the NNUH cohort, the percentage of all term breech presentations that were undiagnosed was 16.2% (27/167) before (year 2015) and 3.5% (5/142) after (year 2020 to 2021) the implementation of universal POCUS screening (p < 0.001). Bayesian regression analysis with informative priors showed that the rate of undiagnosed breech was 71% lower after the implementation of universal ultrasound (RR, 0.29; 95% CrI 0.20, 0.38) with a posterior probability greater than 99.9%. Among the pregnancies with breech presentation, there was also a very high probability (>99.9%) of reduced rate of low Apgar score (<7) at 5 minutes by 77% (RR, 0.23; 95% CrI 0.14, 0.38). There was moderate to high probability (posterior probability: 89.5% and 85.1%, respectively) of a reduction of HIE (RR, 0.32; 95% CrI 0.0.05, 1.77) and extended perinatal mortality rates (RR, 0.21; 95% CrI 0.01, 3.00). Using informative priors, the proportion of all term breech presentations that were undiagnosed was 69% lower after the initiation of universal POCUS (RR, 0.31; 95% CrI 0.21, 0.45) with a posterior probability greater of 99.9%. There was also a very high probability (99.5%) of a reduced rate of low Apgar score (<7) at 5 minutes by 40% (RR, 0.60; 95% CrI 0.39, 0.88). We do not have reliable data on number of facility-based ultrasound scans via the standard antenatal referral pathway or external cephalic versions (ECVs) performed during the study period.

CONCLUSIONS

In our study, we observed that both a policy of routine facility-based third trimester ultrasound or POCUS are associated with a reduction in the proportion of term breech presentations that were undiagnosed, with an improvement in neonatal outcomes. The findings from our study support the policy of third trimester ultrasound scan for fetal presentation. Future studies should focus on exploring the cost-effectiveness of POCUS for fetal presentation.

Pain After Preoperative Ultrasound Guided Hip Injections for Total Hip Arthroplasty: A Pilot Randomized Controlled Trial

Introduction. Hip replacement is a frequently performed and highly successful treatment for patients with end stage osteoarthritis. Advances in technique and pain management have allowed for rapid mobilization and early discharge after surgery. We hypothesize that pre-incision intra-articular injection of local anesthetic with epinephrine under image guidance combined with post incision peri-articular injection (PAI) may be more effective than PAI alone. Methods. A prospective, randomized, controlled, comparative investigation at a single institution of 41 patients undergoing THA who received standard 30 mL post-arthrotomy, PAI of ropivacaine with epinephrine under direct visualization after prosthesis implantation before closure or an equivalent dose divided into a 10 mL pre-incision, ultrasound guided intra-articular injection and a 20 mL post-arthrotomy PAI. Results. 42 patients were included in this study before its early conclusion with 22 patients in the treatment group and 20 in the control group. There were no significant differences in age, BMI or ASA scores. Additionally, there were no significant differences noted when comparing groups by postoperative outcome measures including OMME, EBL, OR time, PACU minutes, and first and last PACU pain score. Furthermore, there were no significant differences in the PROMs evaluated. Discussion. The addition of ultrasound guided pre-incision intra-articular injection to the standard PAI had no benefit when compared with standard PAI during a THA. Portable mobile phone based ultrasound devices provide a cost effective way to perform musculoskeletal blocks, and further studies on their use and comparative accuracy is warranted. A novel technique for confirmation of injection location is described.

Ultrasensitive Aptasensors for the Detection of Viruses Based on Opto-Electrochemical Readout Systems

Viral infections are becoming the foremost driver of morbidity, mortality and economic loss all around the world. Treatment for diseases associated to some deadly viruses are challenging tasks, due to lack of infrastructure, finance and availability of rapid, accurate and easy-to-use detection methods or devices. The emergence of biosensors has proven to be a success in the field of diagnosis to overcome the challenges associated with traditional methods. Furthermore, the incorporation of aptamers as bio-recognition elements in the design of biosensors has paved a way towards rapid, cost-effective, and specific detection devices which are insensitive to changes in the environment. In the last decade, aptamers have emerged to be suitable and efficient biorecognition elements for the detection of different kinds of analytes, such as metal ions, small and macro molecules, and even cells. The signal generation in the detection process depends on different parameters; one such parameter is whether the labelled molecule is incorporated or not for monitoring the sensing process. Based on the labelling, biosensors are classified as label or label-free; both have their significant advantages and disadvantages. Here, we have primarily reviewed the advantages for using aptamers in the transduction system of sensing devices. Furthermore, the labelled and label-free opto-electrochemical aptasensors for the detection of various kinds of viruses have been discussed. Moreover, numerous globally developed aptasensors for the sensing of different types of viruses have been illustrated and explained in tabulated form.