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PubMed2006

Acid gastroesophageal reflux reports in infants: a comparison of esophageal pH monitoring and multichannel intraluminal impedance measurements.

Twenty-four-hour tracings generated from combined esophageal pH and multichannel intraluminal impedance measurements of 14 infants (nine males, median age 3.5 months) were examined retrospectively. For each tracing, two acid reflux assessment reports were generated using either pH monitoring alone or pH monitoring combined with impedance. Significantly fewer acid reflux episodes were detected using pH monitoring combined with impedance when compared to pH monitoring alone (25.1+/-4.0 versus 99.9+/-18.3 episodes/patient, p=.001). Estimates of esophageal acid exposure using pH monitoring alone were two-fold higher (137.4+/-23.7 versus 66.6+/-15.9 min/patient, p=.002) than estimates derived using both techniques. Of the total acid reflux episodes detected by pH monitoring alone, 71.8% could not be confirmed by combined pH and impedance. Detection of significant numbers of "pH-only" episodes raises concerns regarding possible over-estimations of acid exposure that may occur when estimates are based solely on esophageal pH monitoring.

Electric Impedance↗
PubMed2005

Cerebral monitoring in the operating room and the intensive care unit - an introductory for the clinician and a guide for the novice wanting to open a window to the brain. Part II: Sensory-evoked potentials (SSEP, AEP, VEP).

An evoked potential differs from the EEG mainly in two ways: 1. The EEG is a random, continuous signal, which arises from the ongoing activity of the outer layers of the cortex. An evoked potential is the brain's response to a repetitive stimulus along a specific nerve pathway. 2.EEG signals range from 10-200 milliVolt (mV). Evoked potentials are smaller in amplitude (1-5-20 microVolt requiring precise electrode positioning and special techniques (signal averaging) to extract the specific response from the underlying EEG "noise". The technique of signal averaging, as originally described by Dawson in 1954 [69J, has been further developed in computer processing. The technique is now used by applying a stimulus repeatedly--preferably at randomized intervals--and to record the evoked response over the corresponding area of the brain, averaging out mathematically the change over the number of stimuli. Rationale for the use of EPs in the OR and the ICU. Evoked potentials (EPs) serve the following major purposes: 1. Monitoring of the functional integrity of neural structures that may be at risk during, for instance, ECC (extracorporeal circulation) or endarterectomy indicating cerebral hypoxia. 2. Monitoring of the effects of anesthetic agents and other centrally active drugs, which, besides the cortex, affect deeper neuronal structures. 3. Orthopedic cases where the spinal cord is at risk such as Harrington rod insertion and removal. 4. Clamping of the abdominal aortic artery during aneurysmectomy resulting in a potential damage of the lower parts of the spinal cord. 5. Clipping of an intracerebral aneurysm, which may be impeding blood flow to vital cerebral textures. 6. An indicator of cerebral hypoxia when the blood pressure is deliberately lowered. 7. Operation on peripheral nerves and nerve roots to identify early trauma. 8. Monitoring the cerebral function during controlled hypothermia when the EEG becomes flat. 9. Monitoring of the pathophysiological conditions after severe head trauma and the effects of therapy. 10. An intraoperative warning device of unsuspected awareness during light anesthesia when movement is abolished by muscle relaxants and cardiovascular responses are modified by vasoactive drugs. In case of the latter the stimulus is a small electrical potential applied to the skin of the hand. Thereafter, the stimulus travels along the specific nervous pathways inducing (= generating) potential activation at various sites. The generation of potential changes at various sites along the pathway is an index for the integrity of the nerve. Thus, the evoked potential can be considered a neurophysiological response (usually of the cortex) to impulses originating from some externally stimulated sensory nerve. They provide a physiological measure of the functional integrity of the sensory nerve pathway, which can be used as a clinical diagnostic tool as well as for intraoperative monitoring. The evoked potential usually is recorded from the specific cortical area corresponding to the stimulus input. The classification of evoked potentials. Stimulating a sensory nervous pathway induces evoked potentials. If the auditory nerve is stimulated by "clicks" from headphones, it is called the auditory evoked potential (AEP). The early part of the AEP waveform (less than 10 msec) is called the Brainstem Auditory Evoked Potential (BAEP) since it reflects the passing of the impulse through the brainstem. If a nerve on the arm or the leg is stimulated by a small electrical current applied to the overlying skin, it is called the Somatosensory Evoked Potential (SSEP). If, however, the retina is stimulated by means of flicker light or a sudden change in a checkerboard pattern, the evoked potential thus recorded over the corresponding cortical area is called the Visual Evoked Potential (VEP). Evoked potentials are used both as a diagnostic tool and as a monitoring technique. As diagnostic tests, evoked potentials are useful to evaluate neurologic disorders such as: a) multiple sclerosis, b) acoustic nerve tumors, and c) optic neuritis. As a monitoring modality, evoked potentials are used during all surgical procedures, which might compromise part of the brain or the spinal cord.

Brain↗
PubMed1981

Repeated 1 hour electrocardiographic monitoring of survivors of myocardial infarction at 6 month intervals: arrhythmia detection and relation to prognosis.

In a study of the relation between ventricular premature beats and sudden death among 1,739 male of myocardial infarction enrolled in the Health Insurance Plan of Greater New York (HIP), patients underwent 1 hour of electrocardiographic monitoring at a baseline examination. During follow-up periods of up to 5 1/2 years, survivors underwent repeated monitoring at 6 month intervals for a maximum of four monitorings. At each monitoring a constant proportion of the men--25 percent--showed complex ventricular premature beats (runs of two or more, R on T phenomenon, bigeminal or multiform beats) during the hour. In comparison with men free of such arrhythmia, those demonstrating these complex forms in a given hour were three times as likely to show such beats in a subsequent monitoring hour. The mortality risk over 3 1/2 years after each of the four monitoring observations was in all cases elevated among men with complex ventricular premature beats. The risk of sudden death over this period was 6 percent for men without and 13 to 17 percent for men with such complexes. A study of the 1,445 men who underwent monitoring both at baseline examination and 6 months later identified the presence of runs of ventricular premature betas in either observation as a particularly important harbinger of sudden death.

Acute Disease↗
PubMed1985

Value of Holter monitoring in identifying risk for sustained ventricular arrhythmia recurrence on amiodarone.

Seventy-four patients with sustained ventricular tachyarrhythmias had 22 +/- 3 hours of Holter monitoring before and after 11 +/- 6 days of amiodarone treatment. On control Holter recordings, 55 patients (group I) had frequent (more than 10 extrasystoles per hour) and/or complex (at least couplets) ventricular ectopic activity (VEA), and 19 patients (group II) had infrequent and simple VEA. A positive Holter monitor response to amiodarone was defined as a decrease in VEA by more than 85% and abolition of all complex VEA. In group I, 34 patients (62%) had a positive Holter monitor response. In group II, 16 patients (84%) had persistent, infrequent and simple VEA and 3 had frequent and/or complex VEA. During a mean follow-up of 13 +/- 12 months, 22 patients (30%) had ventricular tachycardia (VT) or sudden death. In group I, VT or sudden death occurred in 6 of 34 (18%) patients with a positive Holter monitor response and 11 of 21 (52%) with a negative Holter monitor response (p less than 0.01), and in group II, VT or sudden death occurred in 5 of 16 patients (31%) with persistent, infrequent and simple VEA. All episodes of VT or sudden death occurred after at least 2 weeks of amiodarone therapy (mean 5 +/- 6 months). The predictive accuracy of a positive Holter monitor response as an indicator for subsequent prevention of sustained ventricular tachyarrhythmias and sudden cardiac death was 82% and for a negative Holter monitor response as an indicator of tachyarrhythmia or sudden death recurrence on therapy it was 52%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Ambulatory esophageal monitoring in noncardiac chest pain.

The esophageal origin of angina-like noncardiac chest pain can be identified with certainty only when spontaneous chest pain episodes are associated with gastroesophageal reflux, abnormal esophageal motility, or both. Since noncardiac chest pain typically occurs infrequently, prolonged monitoring is required to establish such an association. Ambulatory esophageal monitoring offers the additional advantages of studying the patient in everyday life and avoiding hospital admission. Although the amplification and storage of 24-hour signals in a portable recorder no longer poses technical problems, the complexity of the analysis of the recorded signals should not be underestimated. For noncardiac chest pain, the most relevant part of the analysis is the association between chest pain episodes and the recorded esophageal signals. To determine whether contraction amplitude or duration during chest pain episodes is abnormal, their measurements are compared with baseline values from the same patient. Fully automated analysis by computer is feasible and, since it avoids observer bias, preferable. The yield of 24-hour monitoring in noncardiac chest pain reported by different groups of investigators varies considerably. Motor abnormalities have been identified as the cause of chest pain in 4.5-18% of patients studied, and reflux in 4.5-25%. In addition, some patients had both dysmotility- and reflux-related pain episodes. As expected, the yield of the technique is higher in patients with frequent pain episodes. In patients who do not experience pain during 24-hour monitoring, the technique cannot provide a firm diagnosis of pain of esophageal origin. Recently, a much higher yield of 24-hour monitoring was reported in patients with noncardiac chest pain admitted to a coronary-care unit. A total of 76% of these patients were found to have either reflux- or dysmotility-related chest pain. Despite its relatively low yield, the addition of esophageal pressure monitoring to ambulatory pH monitoring is worthwhile and probably also cost-effective in patients with frequent episodes of unexplained chest pain.

Ambulatory Care↗
PubMed1981

Continuous transcutaneous oxygen monitoring in fetal surveillance during labor.

Continuous transcutaneous oxygen (PtcO2) monitoring is a noninvasive technique for recording changes in central oxygenation. PtcO2 monitoring has been for some years a routine method in neonatal and adult intensive care. The technique is a potential tool in fetal surveillance during labor. Some recently published studies which have been critical of the use of PtcO2 monitoring in the delivery room reveal a lack of thorough understanding of the limitations of the technique. From the author's experience with the technique, it is obvious that, when the PtcO2 electrode is attached according to recommendations and when the monitoring situation fulfills certain criteria, PtcO2 reliably reflects changes in the fetal oxygenation during labor and may be used for the diagnosis of true hypoxemia. PtcO2 monitoring does not replace any other available routine monitoring for fetal surveillance, but when the technique is refined, it may become an additional means of diagnosing fetal jeopardy. As a research parameter, PtcO2 monitoring has already contributed to a more diversified understanding of the process of fetal asphyxia.

Adult↗
PubMed1979

Combined (stressed and non-stressed) antenatal fetal heart rate monitoring.

Acceleration patterns of the fetal heart rate, or a normal heart rate during spontaneous contractions, were used as a short weekly screening test to evaluate fetal well-being in 1102 high-risk pregnancies. When accelerations or contractions were absent during the initial screening, oxytocin was administered to stimulate uterine contractions. The mean duration of the antenatal monitoring was 18.5 min when the initial antenatal monitoring was normal, but 38.8 min when the initial results were uncertain. Oxytocin was administered to 38% of patients. This reduced the number of occasions where the diagnosis was uncertain from 46.6% to 12%. Patients with uncertain antenatal fetal monitoring had significantly more late decelerations during labor as well as newborns with low Apgar scores when compared to those with normal antenatal monitoring. Patients with abnormal antenatal monitoring (positive stress test) had significantly more low 5-min Apgar scores, late decelerations during labor and growth-retarded infants than the patients with normal antenatal fetal monitoring. Only 1 intrauterine death occurred within 7 days of a normal antenatal heart rate recording. No preventable fetal deaths occurred when antenatal monitoring demonstrated an acceleration pattern of the fetal heart rate.

Female↗
PubMed2006

Effects of time pressure on verbal self-monitoring: an ERP study.

The Error-Related Negativity (ERN) is a component of the event-related brain potential (ERP) that is associated with action monitoring and error detection. The present study addressed the question whether or not an ERN occurs after verbal error detection, e.g., during phoneme monitoring. We obtained an ERN following verbal errors which showed a typical decrease in amplitude under severe time pressure. This result demonstrates that the functioning of the verbal self-monitoring system is comparable to other performance monitoring, such as action monitoring. Furthermore, we found that participants made more errors in phoneme monitoring under time pressure than in a control condition. This may suggest that time pressure decreases the amount of resources available to a capacity-limited self-monitor thereby leading to more errors.

Adolescent↗
PubMed2004

Extended/advanced monitoring techniques in gastrointestinal endoscopy.

The practice of sedation and analgesia is under increasing scrutiny by numerous regulatory agencies, with the aim of making these procedures safer and reducing the incidence of cardiopulmonary complications during GI endoscopy. As we move toward more evidence-based medicine, new technologies will have to be assessed in a manner that demonstrates their efficacy and utility in clinical practice. Although there have been no controlled studies examining whether more intensive monitoring during endoscopy improves outcomes, extended monitoring with capnography seems to offer an advantage over conventional monitoring in that, by providing a real-time indication of any change in adequate ventilation before oxygen desaturation occurs, it can detect early phases of respiratory depression, which can allow a more precise and safer titration of medications. There is a close agreement among experts that capnography may reduce the risk of adverse outcomes during deep sedation; therefore, its use should be required for patients undergoing advanced endoscopic procedures with the potential for deep sedation. Extended monitoring with capnography should also be endorsed whenever propofol is considered as an alternative to standard sedation with a benzodiazepine or narcotic. Our understanding of the clinical application of techniques for monitoring of depth of sedation is in its infancy, and its full contribution to the practice of endoscopy has yet to be determined. Their potential role in improving sedation practice during endoscopy needs to be confirmed by controlled trials. If we consider the lack of proven efficacy of these emerging monitoring techniques in reducing the adverse outcomes associated with sedation and analgesia, the importance of appropriate monitoring cannot be overemphasized. However, it is vital for the endoscopist to be thoroughly familiar with the type of sedation chosen, to be able to recognize the various levels of sedation, and, above all, to rescue patients should they unintentionally progress to a deeper level of sedation than intended.

Procedural Sedation↗
PubMed2006

Adapting electronic adherence monitors to standard packages of topical medications.

Adherence to topical medications is poorly characterized. Electronic monitors can provide objective adherence data, but these monitors are not designed to work with tubes of medications. We sought to adapt standard electronic monitors to commonly used medication tubes. An adapter was created to fit over standard medication tubes. Screw threads on the adapter were designed to fit standard electronic monitors. Adapters and monitors were tested with tubes of gel, ointment, and cream over an 8-week test period during which the adapters were opened and closed twice daily. The adapters were easily mated to both plastic and aluminum topical medication tubes. The bond between the adapter and the tube was maintained throughout the study. Electronic monitors were 100% accurate at identifying medication events over the study period. We conclude that adapting existing electronic monitors to medication tubes should facilitate a much better understanding of adherence to topical treatment.

Administration, Topical↗
PubMed2005

Recurrent laryngeal nerve electrophysiologic monitoring in thyroid surgery: the standard of care?

Reports in the literature suggest that the rate of transient and permanent vocal fold immobility (VFI) after thyroid surgery is 4% to 7% and 1% to 4%. The intraoperative use of nerve integrity monitors has been advocated to reduce the incidence of VFI during thyroid surgery. The purpose of this study was to compare postoperative VFI after unmonitored and monitored thyroid surgical procedures. The charts of 136 consecutive patients who underwent thyroid surgery from 1998 to 2003 were retrospectively surveyed. Fifty-four patients had total thyroidectomies, bringing the total recurrent laryngeal nerves (RLNs) dissected to 190. Three of 190 (1.6%) and 7 of 190 (3.7%) RLNs dissected had permanent and transient vocal fold dysfunction. Overall, 107 RLNs were unmonitored compared with 83 RLNs that were monitored. Unmonitored and monitored RLNs had a 4 of 83 (4.8%) versus 3 of 107 (2.8%) rate of transient VFI (P > 0.05). Unmonitored and monitored RLNs had a 1 of 107 (0.9%) versus 2 of 83 (2.4%) rate of permanent VFD (P > 0.05). Electrophysiologic RLN monitoring was not demonstrated in this study to reduce the incidence of transient or permanent VFI after thyroid surgery. Electrophysiologic RLN integrity does not always translate into clinical postoperative vocal fold mobility. Electrophysiologic RLN monitoring may support that the RLN was not severed in the patient with postoperative VFI.

Electrophysiology↗
PubMed2006

Continuous EEG-SEP monitoring of severely brain injured patients in NICU: methods and feasibility.

AIMS: To evaluate the feasibility of a continuous neurophysiologic monitoring (electroencephalography (EEG)-somatosensory evoked potentials (SEPs)) in the neuro-intensive care unit (NICU), taking into account both the technical and medical aspects that are specific of this environment. METHODS: We used an extension of the recording software that is routinely used in our unit of clinical neurophysiology. It performs cycles of alternate EEG and SEP recordings. Raw traces and trends are simultaneously displayed. Patient head and stimulator box are placed behind the bed and linked to the ICU monitoring terminal through optic fibers. The NICU staff has been trained to note directly clinical events, main artefacts and therapeutic changes. The hospital local area network (LAN) enables remote monitoring survey. RESULTS: Continuous EEG (CEEG)-SEP monitoring was performed in 44 patients. Problems of needle detachment were seldomly encountered, thanks to the use of a sterile plastic dressing, which covers needles. We never had infection or skin lesions due to needles or the electrical stimulator. The frequent administration of sedative at high doses prevented us from having a clinically valuable EEG in several cases but SEPs were always monitorable, independently of the level of EEG suppression. The diagnosis of seizures and non-epileptic status was based on raw EEG, while quantitative EEG (QEEG) was used to quantify ictal activity as a guide to treatment. CONCLUSIONS: EEG and EP waveforms collected in NICU were of comparable quality to routine clinical measurements and contained the same clinical information. A continuous SEP monitoring in a comatose and sedated patient in NICU is not technically more difficult and potentially less useful than in operating room. This monitoring appears to be feasible provided the observance of some requirement regarding setting, electrodes, montages, personnel integration, consulting and software.

Brain Injuries↗
PubMed2004

Therapeutic drug monitoring of cyclosporine.

Therapeutic drug monitoring of cyclosporine has been established as part of the routine clinical treatment for patients after organ transplantation. The inability to define optimal dose (maximize efficacy/minimize toxicity) has been a problem related to drug monitoring of cyclosporine. The original cyclosporine formula showed high intra-patient and inter-patient variability and low bioavailability. The microemulsion formulation of cyclosporine (Neoral) was introduced to address the absorption problems related to the original cyclosporine formulation. With the introduction of Neoral, renewed interest in methods of therapeutic drug monitoring brought us from trough monitoring (C0) to levels measured 2 hours after dosing (C2). The pharmacokinetic rationale for using C2 to monitor patients receiving Neoral has demonstrated a reduced incidence of rejection in de novo patients and improvements in safety profile in both renal and hepatic transplant recipients. Monitoring C2 levels is a more precise method for optimizing cyclosporine dosing and a better way to individualize therapy. Further data are required from prospective trials to evaluate the clinical benefits of adopting C2 monitoring in cardiac and lung transplant recipients as well as in long-term maintenance patients.

Area Under Curve↗
PubMed2005

Evaluation of river water quality monitoring stations by principal component analysis.

The development of a surface water monitoring network is a critical element in the assessment, restoration, and protection of stream water quality. This study applied principal component analysis (PCA) and principal factor analysis (PFA) techniques to evaluate the effectiveness of the surface water quality-monitoring network in a river where the evaluated variables are monitoring stations. The objective was to identify monitoring stations that are important in assessing annual variations of river water quality. Twenty-two stations used for monitoring physical, chemical, and biological parameters, located at the main stem of the lower St. Johns River in Florida, USA, were selected for the purpose of this study. Results show that 3 monitoring stations were identified as less important in explaining the annual variance of the data set, and therefore could be the non-principal stations. In addition, the PFA technique was also employed to identify important water quality parameters. Results reveal that total organic carbon, dissolved organic carbon, total nitrogen, dissolved nitrate and nitrite, orthophosphate, alkalinity, salinity, Mg, and Ca were the parameters that are most important in assessing variations of water quality in the river. This study suggests that PCA and PFA techniques are useful tools for identification of important surface water quality monitoring stations and parameters.

Calcium↗
PubMedDate not supplied

[Usefulness of facial nerve monitoring during parotidectomy].

OBJECTIVE: To analyse the usefulness of facial nerve monitoring by continuous electromyography during parotidectomy. PATIENTS AND METHODS: Fifty-two consecutive patients who underwent parotidectomy (27 unmonitored and 25 monitored) between 1987 and 1998. Both groups had a similar distribution of superficial and total parotidectomy. RESULTS: Facial nerve monitoring reduced the incidence and severity of facial nerve paralysis independently of the kind of surgery performed. The incidence of temporary facial paralysis was significantly lower in the monitored group (36%) than in the unmonitored group (70%) (p = 0.013). The rates of permanent deficit were 4% for the monitored group and 30% for the unmonitored group (p = 0.025). CONCLUSIONS: The results suggest that intraoperative facial nerve monitoring reduces the incidence of postoperative facial deficit. The routine use of facial nerve monitoring is controversial. However, it is considered useful in surgery where there is a higher risk of injury to the facial nerve such as total parotidectomy, re-interventions or chronic inflammatory conditions.

Adolescent↗
PubMed1979

A controlled trial of the differential effects of intrapartum fetal monitoring.

A controlled prospective study of the differential effects of intrapartum fetal monitoring on mothers and infants has been conducted at Denver General Hospital, Denver, Colorado. A total of 690 high-risk obstetric patients in labor were randomly assigned to one of three monitoring groups--auscultation, electronic fetal monitoring alone, or electronic monitoring with the option to scalp sample. There were no differences in immediate infant outcomes in any measured category (Apgar scores, cord blood gases, neonatal death, neonatal morbidity, nursery course) among the three groups. There were no differences in rates of infant or maternal infections. The cesarean section rate was markedly increased in the electronically monitored groups, especially in the electronically monitored alone (18%) as compared with the auscultated (6%) (P less than 0.005). In this controlled trial electronic monitoring did not improve neonatal outcomes and the mothers were at increased risk of cesarean section.

Apgar Score↗
PubMed1996

Multicenter randomized clinical trial of home uterine activity monitoring: pregnancy outcomes for all women randomized.

OBJECTIVE: Our purpose was to evaluate the impact of home uterine activity monitoring on pregnancy outcomes among women at high risk for preterm labor and delivery. STUDY DESIGN: Women at high risk for preterm labor at three centers were randomly assigned to receive high-risk prenatal care alone (not monitored) or to receive the same care with twice-daily home uterine activity monitoring without increased nursing support (monitored). There were 339 women with singleton gestations randomized with caregivers blinded to group assignment. The two groups were medically and demographically similar at entry into the study. RESULTS: Women in the monitored group had prolonged pregnancy survival (p = 0.02) and were less likely to experience a preterm delivery (relative risk 0.59; p = 0.04). Infants born to monitored women with singleton gestations were less likely to be of low birth weight (< 2500 gm; relative risk 0.47, p = 0.003), and were less likely to be admitted to a neonatal intensive care unit (relative risk 0.5, p = 0.01). CONCLUSION: These data show, among women with singleton gestations at high risk for preterm delivery, that the use of home uterine activity monitoring alone, without additional intensive nursing care, results in improved pregnancy outcomes, including prolonged gestation, decreased risk for preterm delivery, larger-birth-weight infants, and a decreased need for neonatal intensive care.

Adult↗
PubMed1998

Ambulatory blood pressure monitoring in pregnancy: what is normal?

OBJECTIVE: Noninvasive 24-hour ambulatory blood pressure monitoring holds great promise as a useful tool in the management of hypertensive pregnancies and pregnancies considered "at risk" for development of preeclampsia. The purpose of this study was to define ambulatory blood pressure monitoring parameters throughout normal pregnancy, including women considered at risk for development of hypertension who continued to have a completely normal pregnancy. STUDY DESIGN: Two hundred seventy-six 24-hour ambulatory blood pressure monitoring studies were made cross-sectionally with use of a Spacelabs 90207 device (validated for use in pregnancy), at one or more of 9 to 17, 18 to 22, 26 to 30, and >30 weeks' gestation. Upper limits of normal were defined as the mean plus 2 SDs for awake and sleep ambulatory blood pressure monitoring results at each stage. RESULTS: Average awake upper limits of normal were 130/77, 132/79, 133/81, and 135/86 mm Hg at the four stages of pregnancy, respectively. Systolic blood pressure fell significantly by 12% to 14% (p < 0.0001) and diastolic blood pressure by 18% to 19% (p < 0.0001) during sleep at all stages of pregnancy. Awake ambulatory blood pressure monitoring systolic measurements were 11 to 12 mm Hg higher than "clinic" measurements (p < 0.001) and diastolic measurements were 5 to 11 mm Hg higher (p < 0.0001) throughout pregnancy. Maximum blood pressure variability ranged from 8 to 13 mm Hg. CONCLUSIONS: The upper limits of normal ambulatory blood pressure monitoring-derived measurements rise slightly as pregnancy progresses. Awake measurements are higher than "clinic" measurements recorded under relaxed conditions by a clinical researcher. The diurnal blood pressure fall and variabilities are similar during pregnancy to those seen in nonpregnant subjects. These data should provide valuable references for further studies of ambulatory blood pressure monitoring in high risk pregnancies.

Blood Pressure Monitoring, Ambulatory↗