Cardiorespiratory Events Research Articles

Temporal Association of Polysomnographic Cardiorespiratory Events With GER Detected by MII‐pH Probe in the Premature Infant at Term

Temporal Association of Polysomnographic Cardiorespiratory Events With GER Detected by MII‐pH Probe in the Premature Infant at Term

Temporal Association of Polysomnographic Cardiorespiratory Events With GER Detected by MII‐pH Probe in the Premature Infant at Term

The aim of the study was to examine temporal association (TA) between polysomnographic cardiorespiratory (CR) events and gastroesophageal reflux (GER) in premature infants with persistent CR events at >39 weeks postmenstrual age and determine whether the use of multichannel intraluminal impedance (MII)-pH probe improves sensitivity of the TA compared with pH probe alone. Seven infants born between 24 and 29 weeks' gestational age with persistent CR events at 39 to 48 weeks' postmenstrual age underwent a polysomnography with MII-pH probe. Symptom index (SI) and symptom-associated probability were calculated for diverse types of reflux and CR events. SI and a Fisher exact test with variable association windows were calculated for obstructive apnea (OA). Odds ratios for an OA given a reflux event and for a reflux event given an OA were determined. With a Fisher exact test, a subject-specific association between MII events and OA was found in the 3 patients who required a fundoplication or had the worse clinical GER. Some level of TA was found with SI and symptom-associated probability in 6 of 7 infants. Association was found for pH > 4 and pH ≤ 4 reflux events. pH-only events with no change of MII had only a limited role in generating CR events. TA between CR events and GER was found in a single-subject-level analysis in some infants with persistent CR events at term. This TA suggests a causal relation between CR and reflux events that was further strengthened by the clinical outcomes of each infant.

Hepatic Resection for the Carcinoid Syndrome in Patients with Severe Carcinoid Heart Disease: Does Valve Replacement Permit Safe Hepatic Resection?

Hepatic resection of metastatic carcinoid cancer can prolong survival and control symptomatic endocrinopathy. Decompensated carcinoid heart disease (CHD) can develop in some patients with metastatic carcinoid cancers, which can preclude operation for resectable hepatic metastases. We hypothesized that outcomes after hepatic resection for patients with the carcinoid syndrome after valve replacement for CHD would be similar to carcinoid patients without CHD. We compared the survival and symptom control after hepatic resection for patients undergoing valve replacement for CHD to carcinoid patients without CHD matched for age, sex, and extent of hepatectomy. Fourteen patients with earlier valve replacement for CHD were compared with 28 carcinoid patients without CHD. All patients had hepatic resection for metastatic carcinoid disease and carcinoid syndrome. Mean age, sex distribution, and extent of hepatectomy (major hepatectomy, 78%) was similar between groups. Mean interval from valve replacement to hepatectomy was 101 days. There was no operative mortality. Major operative morbidity, inclusive of operative blood loss and cardiorespiratory events, occurred in 28.5% and 14.2% for CHD and non-CHD groups, respectively (p = 0.16). Symptom-free survival for CHD and non-CHD groups was 69% and 81% at 1 year (p = 0.22) and 61% and 44% (p = 0.17) at 5 years, respectively. Octreotide-free survival after hepatectomy 69% and 84% (p = 0.15) at 1 year and 62% and 52% (p = 0.29) 5 years, respectively. Overall survival CHD and non-CHD groups 100% at 1 year and 100% and 70% (p = 0.002) 5 years. Valve replacement for severe CHD is safe and hepatic resection is associated with similar outcomes as patients without CHD undergoing hepatic resection for carcinoid syndrome. Identifying resectable hepatic metastases from carcinoids in patients with severe CHD should prompt valve replacement and interval hepatic resection.

Can computer-aided personalized sedation bridge troubled waters?

The issue of propofol administration by nonanesthesiologists for upper endoscopy and colonoscopy remains controversial. A recent study investigated the efficacy and safety of a novel computer-assisted personalized sedation device. Patients sedated using the device experienced fewer serious cardiorespiratory events than patients undergoing standard sedation by bolus administration using a hand-held syringe.

Variation in Diagnosis of Apnea in Moderately Preterm Infants Predicts Length of Stay

Apnea of prematurity is one of the most common diagnoses in the NICU. Because resolution of apnea is a usual precondition for discharge from the hospital, different monitoring practices might affect length of stay for premature infants. Our objective was to compare the proportion of 33 to 34 weeks' gestational age infants diagnosed with apnea in different NICUs and to assess whether variability in length of stay would be affected by the rate of documented apnea. This was a prospective cohort study of moderately preterm infants who survived to discharge in 10 NICUs in Massachusetts and California. The study population comprised 536 infants born between 33 and 34/7 weeks of which 264 (49%) were diagnosed with apnea. The mean postmenstrual age at discharge was higher in infants diagnosed with apnea compared with those without apnea (36.4 ± 1.3 vs 35.7 ± 0.8; P < .001, analysis of variance). Significant inter-NICU variation existed in the proportion of infants diagnosed with apnea (range: 24%-76%; P < .001). Postmenstrual age at discharge also varied between NICUs (range: 35.5 ± 0.6 to 36.7 ± 1.5 weeks; P < .001). As much as 28% of the variability in postmenstrual age at discharge between NICUs could be explained by the variability in the proportion of infants diagnosed with apnea. NICUs vary in the proportion of moderately preterm infants diagnosed with apnea, which significantly affects length of stay. Standardization of monitoring practices and definition of clinically significant cardiorespiratory events could have a significant impact on reducing the length of stay in moderately preterm infants.

Apparent life-threatening events: Assessment, Risks, Reality

Apparent life-threatening events (ALTEs), because of their prevalence as well as their potential to hide serious diseases and consume significant medical resources, remain a challenge for physicians caring for infants. In this review, we focused on the assessment of the well-appearing infant for the most serious diagnoses, namely serious bacterial infections, seizure disorders, child abuse, metabolic disorders and severe apnoea with hypoxemia. Our extensive review of the literature has highlighted the difficulties physicians are facing in this evaluation, especially for the youngest infants (aged less than 2 months). Large-scale prospective studies are needed to identify risk factors and to guide physicians as to who should be investigated and the minimal investigation needed to avoid missing such conditions as serious bacterial infection, abusive head injury or repeated severe cardiorespiratory events. While infants with severe forms of metabolic disorders typically present with evident signs and symptoms, less severe forms of metabolic disorders, seizure disorders, and some forms of child abuse will often be diagnosed only when recurrent events are investigated.

162 Long-Term Cardio-Respiratory Regulation in Children with Rett Syndrome

Background: The cardiac and respiratory function requires an intricate coordination of afferent/efferent signals at several levels to secure homeostasis. Rett syndrome is characterised by a functional disintegration of physiological functions. Autonomic function in Rett syndrome has been studied mainly during short time spans (minutes-1 hour). In order to capture the full complexity of the autonomic function – a long-term study of the cardio-respiratory regulation was performed. Methods: Patients with Rett syndrome in the Stockholm area were studied during one week in their home environment (n=15). Heart rate and breathing were recorded via standard three-lead ECG electrodes. The depth and frequency of respiratory movements were measured via changes in impedance. Oxygenation was measured by pulse oxymetry. Care takers were asked to fill out a form during the monitoring enabling us to analyze the correlation between behaviour and cardio-respiratory reactions. Results: All subjects revealed respiratory dysfunction and a majority had bradycardia and/or tachycardia. In accordance with our previous findings, disturbances in cardio-respiratory function were present both when awake and asleep. Interestingly, there were pronounced variations in cardio-respiratory regulation from day to day and even from hour to hour in an individual patient. Furthermore, we also observed variations in cardio-respiratory events between individuals and situations. Conclusions: Cardio-respiratory function in children with Rett syndrome is characterised by dramatic instability during wakefulness and sleep and differ among individuals. Cardio-respiratory regulation varies from hour to hour and between different situations in the individual Rett girl. Therefore, a long-term monitoring is decisive for adequate diagnostics and treatment.

The role of combined multichannel intraluminal impedance and pH-monitoring in newborn with gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a relevant problem in first months of life and its early diagnosis and its appropriate therapy represent a real challenge for neonatologists.Multichannel Intraluminal Impedance associated with esophageal pH-monitoring (MII/pH) has been recently introduced to study GERD in infants. This technique, which is safe and with a good compliance, presents an elevated accuracy in identifying refluxes independently from their pH. The main aim of this review is to analyse data in literature on the use of MII/pH in neonates.We have considered recent studies published in PubMed in which MII is used in neonates and infants with GER: 26 studies focus on GER physiopathology and on the advantages of using MII in addition to pH-monitoring, 13 on symptoms associated with refluxes (in particular cardio-respiratory events and apnoeas) and 13 on therapy (5 on body position, 3 on thickened formulas, 1 on fortified milk and 4 on drugs).We underline the role of MII/pH in studying GERD in neonates, in which non acid-refluxes result prevalent, because of the buffering effects of milk, and in which the majority of symptoms arerelated to non-acid or weakly-acid GER. MII/pH can be considered a good technique even in the evaluation of the temporal relation between refluxes and symptoms and in the analysis of the benefits obtained by pharmacological and non-pharmacological therapy.The increasing application of MII/pH can help neonatologists to comprehend GER physiopathology, to diagnose GER and GERD and to treat better its symptoms in first months of life.

The Global Burden of Air Pollution on Mortality: The Need to Include Exposure to Household Biomass Fuel–Derived Particulates

Anenberg et al. (2010) demonstrated that global mortality associated with outdoor ozone and particulate matter (PM) exposure has been underestimated and that anthropogenic atmospheric PM rather than ozone is the main contributor to death. Although we acknowledge that their investigation was concerned with outdoor air pollution alone, we feel that attention should be drawn to the burden of disease from household air pollution. Half the world’s population is exposed to fine PM [< 2.5 μm in aerodynamic diameter (PM2.5)] in their own homes as a consequence of using biomass fuels such as wood, charcoal, and animal/crop residues for cooking, lighting, and heating. Such exposure is prolonged, extensive, and overlooked by examination of atmospheric models alone (Torres-Duque et al. 2008). Combustion of biomass fuels has been repeatedly demonstrated to produce high concentrations of domestic air pollution, with PM2.5 exposures extending in to the milligram per cubic meter range, orders of magnitude above concentrations from exposure to anthropogenic particulate pollution outdoors (Regalado et al. 2006). Rural populations, and women in particular, are likely to have particularly high indoor exposures because of the extended time spent on cooking and household activity (Mestl et al. 2007). Anenberg et al. (2010) used exposure– response functions derived from epidemiological studies of outdoor air, which emphasize cardiopulmonary mortality in older cohorts. Household air pollution from biomass fuel combustion contributes to chronic respiratory disease and cardiorespiratory events. However, it is particularly implicated in pneumonia in young children (Dherani et al. 2008) and has been ranked the 11th most important risk factor in global mortality, predominantly because of the association with infection (Ezzati et al. 2004). These early deaths would contribute considerably to the estimate of years of life lost due to PM. We agree with Anenberg et al. (2010) that anthropogenic PM is an important global cause of premature death. However, outdoor levels report only part of the picture and may significantly underestimate the total PM-related mortality burden. Recent work (Pope et al. 2009) has brought together data on exposure–response functions for outdoor air pollution and cigarette smoking, and there is a need for additional similar work to integrate studies on indoor biomass combustion (Ezzati et al. 2000). These studies would help clarify the exposure–response function of household air pollution as well as assist in the important process of identifying the most cost-efficient means of reducing exposure among the 3 billion people who bear the health burden from high particulate concentrations at home.

Upper airway reflexes in response to gastric reflux

Gastric reflux, and especially laryngopharyngeal reflux, occur several times a day in every infant. Most often, this does not pose any problem. However, in certain conditions, the contact between the refluxate and the upper airway mucosa can trigger several reflexes leading to cardiorespiratory inhibition. This is especially true for the laryngeal chemoreflexes, which are triggered by laryngeal penetration of gastric refluxate. The laryngeal chemoreflexes are held responsible for a subset of apnoeas of prematurity, many apparent life-threatening events, and probably some cases of sudden infant death syndrome. Although a number of experiments in newborn animals, as well as a few clinical studies in human infants, have been performed in the last 40 years to evaluate laryngeal chemoreflexes, their true role in neonatal cardiorespiratory events is still highly debated. In addition, many uncertainties persist with regard to treatment and prevention of their potentially dramatic consequences.

Concomitant Ceftriaxone and High-Concentration Intravenous Calcium Therapy in Adult Critical Care Patients: A Matched Cohort Study

Based on case reports in infants, the safety of concomitant use of ceftriaxone and intravenous calcium in all ages has recently come under challenge. Systematic population-based data to guide clinicians with respect to this risk are, however, lacking. To determine whether concomitant administration of ceftriaxone and intravenous calcium was associated with the occurrence of severe cardiorespiratory events or death in critically ill adults. We performed a matched-cohort study from retrospective data of adults admitted to intensive care units (ICUs) in Calgary, Canada, who were provided continuous high-dose intravenous calcium. Those who received ceftriaxone while on continuous renal replacement therapy were considered exposed. Up to 3 unexposed patients were selected by matching on a number of prognostic factors from the remaining subjects not concurrently exposed to ceftriaxone and calcium. Univariate methods and multivariate conditional logistic regression were used for statistical analysis. We identified 142 patients exposed to the implicated combination who could be matched to at least one unexposed patient. Hospital mortality was 66% in the exposed versus 63% in unexposed patients (p = 0.442). ICU length of stay, ICU mortality, hospital length of stay, and the frequency of acute oxygenation events were all similar by univariate analysis. Multivariate conditional logistic regression modeling failed to find a significant association between exposure and hospital mortality (adjusted OR 1.15, 95% CI 0.65 to 2.04) or other relevant outcomes. In this high-risk group, administration of high concentrations of calcium and concurrent ceftriaxone was not significantly associated with greater mortality or adverse outcomes compared to matched unexposed patients. Although this was an underpowered study and rare adverse effects from the interaction of these 2 compounds cannot be completely excluded, these data provide overall reassurance of the safety of this combination in the majority of critically ill adults.

Characterization of cardiorespiratory events following gastroesophageal reflux in preterm infants

ObjectiveTo characterize cardiorespiratory events in preterm infants following both acid and non-acid GER as detected by pH and multiple intraluminal impedance (MII).Study DesignTwelve hour overnight studies were performed in 71 preterm infants (gestational age 29.4±3.0 wks, birth weight 1319±496 gm). Apnea ≥10 seconds in duration, bradycardia ≤80 bpm and oxygen desaturation ≤85% that occurred within 30 seconds after the initiation of GER were classified as associated with GER.Result12,957 cardiorespiratory events and 4164 GER episodes were documented. Less than 3% of all cardiorespiratory events were preceded by GER constituting 3.4% of apnea, 2.8% of oxygen desaturation and 2.9% of bradycardia events. GER did not prolong cardiorespiratory event duration or increase severity. In contrast, GER was associated with a shorter duration of oxygen desaturation events (7.8±4.6 vs 6.3±5.6 sec, p<.05).ConclusionGER is rarely associated with cardiorespiratory events, and has no detrimental effect on cardiorespiratory event duration or severity.

Postnatal autonomic activity in the preterm lamb

Background Early postnatal abnormalities of autonomic nervous system (ANS) activity, including at baseline and following cardiorespiratory challenge, are involved in apneas–bradycardias of prematurity, apparent life-threatening events of infancy and sudden infant death syndrome. Literature data suggest that baseline ANS activity does not mature normally after premature birth. Objectives This study performed in preterm lambs was aimed at assessing ANS maturation at baseline and following laryngeal chemoreflexes (LCR), a group of reflexes triggered by the contact of liquids with the laryngeal mucosa. Methods Heart rate variability (HRV) and baroreflex sensitivity (BRs) were measured at baseline and after LCR during polysomnographic recordings performed in five non-sedated lambs born 15 days prematurely. Laryngeal chemoreflexes were induced by distilled water or acid (pH 2) during sleep and wakefulness on postnatal days 7 (D7) and 14 (D14, full-term equivalence). Results While the life-threatening cardiorespiratory events of the LCR observed at D7 were no longer present at D14, baseline and post-LCR HRV and BRs indices were significantly lower at D14 compared to D7 (up to p < 0.001). These results suggest that an initial autonomic overactivity was present at D7 and normalized at D14. Conclusion The autonomic cardiac and baroreflex control appears to follow a specific evolution in the preterm compared to the full-term newborn lamb, with an important initial autonomic stress, which normalizes at an age equivalent to full-term. Potential relevance of these findings in relation to anomalies of cardiac control in the early postnatal period, such as apneas–bradycardias of prematurity, apparent life-threatening events of infancy and sudden infant death syndrome, awaits further studies.

Risk of fever and sepsis evaluations after routine immunizations in the neonatal intensive care unit

Premature infants can experience cardiorespiratory events such as apnea after immunization in the neonatal intensive care unit (NICU). These changes in clinical status may precipitate sepsis evaluations. This study evaluated whether sepsis evaluations are increased after immunizations in the NICU. We conducted a retrospective cohort study of infants older than 53 days who were vaccinated in the NICU at the KPMCP (Kaiser Permanente Medical Care Program). Chart reviews were carried out before and after all immunizations were administered and for all sepsis evaluations after age 53 days. The clinical characteristics of infants on the day before receiving a sepsis evaluation were compared between children undergoing post-immunization sepsis evaluations and children undergoing sepsis evaluation at other times. The incidence rate of sepsis evaluations in the post-immunization period was compared with the rate in a control time period not following immunization using Poisson regression. A total of 490 infants met the inclusion criteria. The rate of fever was increased in the 24 h period after vaccination (2.3%, P<0.05). The incidence rate of sepsis evaluations was 40% lower after immunization than during the control period, although this was not statistically significant (P=0.09). Infants undergoing a sepsis evaluation after immunization were more likely to have an apneic, bradycardic or moderate-to-severe cardiorespiratory event in the day before the evaluation than were infants undergoing sepsis evaluations at other times (P<0.05). Despite an increase in fever and cardiorespiratory events after immunization in the NICU, routine vaccination was not associated with increased risk of receiving sepsis evaluations. Providers may be deferring immunizations until infants are clinically stable, or may have a higher threshold for initiating sepsis evaluations after immunization than at other times.

Luxación cervical C6-C7

Ellis-van Creveld syndrome is a rare type of developmental chondroectodermal dysplasia. We report the case of a 32-year-old woman with this syndrome who was scheduled for cesarean section. She had no related heart defect. A spinal block was attempted but after confirming that no sensory blockade had been achieved, general anesthesia was administered. Both the operation and the anesthetic procedure were without complications. The clinical manifestations of Ellis-van Creveld syndrome are short-limbed dwarfism, postaxial polydactyly, fingernail dysplasia, cleft palate and lips, and heart defects. Diagnosis is based on clinical manifestations and radiography. Treatment involves correction of heart defects and orthopedic problems. Perioperative airway management problems may develop. A preoperative echocardiogram should be done to assess heart function and ascertain anatomical abnormalities. Thoracic deformities may make mechanical ventilation difficult and there is risk of barotrauma. Intraoperative management requires rapid control of the airway and prevention of bronchial aspiration. Vigilance in preventing hemodynamic instability and myocardial depression is essential. Postoperative analgesia must be managed carefully and adverse cardiorespiratory events avoided.

Air Pollution and Community Health: Quantifying Acute Cardio-Respiratory Events Attributable to SO2 and NO2 Exposure

Air Pollution and Community Health: Quantifying Acute Cardio-Respiratory Events Attributable to SO2 and NO2 Exposure

Measuring Communication in the Surgical ICU: Better Communication Equals Better Care

The Joint Commission on the Accreditation of Healthcare Organizations reports that communication breakdowns are responsible for 85% of sentinel events in hospitals. Patients in surgical ICUs are the most vulnerable to communication errors. Fellows and residents are an integral part of the surgical ICU team, but little is known about resident-fellow communication and its impact on surgical ICU patient outcomes. The objective of this study is to describe resident-fellow patient care communication patterns in the surgical ICU and correlate established communication patterns with short-term outcomes. A prospective observational trial was conducted for 136 consecutive surgical ICU days. We evaluated resident-fellow communication of four cardiorespiratory events: hypotension, new arrhythmias, tachypnea, and desaturation. We prospectively defined three short-term outcomes: improved, not improved, and worse. An intervention was attempted to improve communication. Three hundred twelve events were collected (166 observational and 146 interventional). PGY3 residents covered approximately 60% of days in both phases. PGY3 residents were responsible for 73% of communication errors in the observational phase and 59% of communication errors in the interventional phase. Communication errors were more likely in the late shift (p < 0.0001). The late shift was responsible for 77% of all communication errors. Communication errors resulted in worse short-term outcomes for cardiorespiratory events (p < 0.0002). Effective communication was a significant predictor of improved short-term outcomes (p < 0.0003). The intervention decreased communication errors in the late shift by 10% (p < 0.052). Communication errors occurred more frequently during the late shift. These communication errors were associated with worsened short-term outcomes. Improved communication in the surgical ICU is a fruitful target to improve clinical outcomes.

Heart rate variability during REM and non-REM sleep in preterm neonates with and without abnormal cardiorespiratory events

Aim Analyse heart rate variability (HRV) of preterm neonates undergoing a polysomnography in relation to the occurrence of abnormal cardiorespiratory events on one hand and the type of sleep states on the other hand. Methods To quantify nonlinear HRV, the numerical noise titration technique is used, adapted to neonatal heart rate data. HRV is calculated for 30 preterm neonates with mean post-conceptional age of 36.4 weeks, divided into three groups according to the occurrence of abnormal events during the polysomnographies and the eventual home monitoring. Results Periods of non-REM sleep have lower noise limit values and can be distinguished significantly from periods of REM sleep and from the total recording period. The presence of abnormal events does not influence this finding. Significant differences between groups are only found during non-REM segments by means of the noise limit value computed via numerical noise titration while the linear HRV parameters were not able to discriminate. Conclusion ECG measurement of a relatively short non-REM sleep period without specific abnormal events is sufficient to define a mature cardiorespiratory pattern in preterm infants.

Very low birth weight infants have only few adverse events after timely immunization

Premature infants should be vaccinated at the appropriate vaccinating age, without correcting for their gestational week and regardless of their weight. Uncertainty with regard to possible severe adverse events exists among physicians. In all, 473 patients with a birth weight under 1500 g were included in a prospective observational study for adverse events that included cardiorespiratory events, local reactions and fever. Three vaccination combinations were used at different time periods. The median birth weight was 910 (375 to 1495) g. Gestational week at birth was 27.6 (22.6 to 34.3). At the time of vaccination, the gestational week was 37.4 (31.5 to 48.3). The frequency of adverse events for local reactions/fever was 2.8% and for apnea/bradycardia it was 10.8%. Apnea appeared significantly more often in children who were younger at the time of immunization. This is in concordance with the fact that they were also younger at birth. If apnea appeared, the chance of the development of bradycardia had an odds ratio of 6.4 (3.2:13.0). Children with higher-grade hemorrhages and/or with periventricular leukomalacia did not experience more adverse events, except fever. Timely vaccination of premature infants with a birth weight under 1500 g is safe, but the occurrence of cardiorespiratory events is related to earlier gestational week.

Evaluation of Cerebral Oxygenation During Procedural Sedation in Children Using Near Infrared Spectroscopy

We evaluate the utility of near infrared spectroscopy monitoring and its correlation to conventional respiratory monitors during changes in cardiorespiratory characteristics during pediatric procedural sedation. In this prospective observational study of 100 children, cerebral oxygenation (rSO(2)), pulse oximetry (SpO(2)), and end-tidal carbon dioxide (etco(2)) were monitored continuously. Values were manually recorded at least every 3 minutes from baseline until 30 minutes after sedative administration, resulting in 1,515 triplicate (simultaneous near infrared spectroscopy/etco(2)/SpO(2)) measurements. Correlations between conventional monitoring characteristics (SpO(2) and etco(2)) and rSO(2) were determined, with focus during adverse cardiorespiratory events. Cerebral oxygenation remained normal in 1,483 of 1,515 measurements (97.9%). rSO(2) decreased significantly during 3 of 13 hypoxic events occurring in 13 patients and during 5 of 17 hypercarbic events occurring in 8 patients, with 15 measurements of greater than 20% decrease from baseline. Cerebral oxygenation increased transiently in 88% of children. During 31 cerebral desaturation recordings, 3 hypoxic recordings (9.3%, always in combination with hypercarbia) and 5 hypercarbic recordings (15.6%) were observed, whereas in 23 (74.2%), cardiorespiratory characteristics were unchanged. There was poor correlation between rSO(2) and both SpO(2) and etco(2), with correlation coefficients of 0.05 (95% confidence interval 0.04 to 0.07) and 0.01 (95% confidence interval -0.01 to 0.02), respectively. Cerebral oxygenation as measured by near infrared spectroscopy demonstrated few significant negative changes during pediatric procedural sedation. Transient cardiorespiratory events seldom altered rSO(2), with hypercarbia having a greater effect than hypoxemia. However, cerebral desaturations frequently occurred without associated cardiorespiratory changes.