Patient-Reported Quality of Recovery after Sedation for Endoscopy in the Elderly.

INTRODUCTION: Although sedation is critical in minimizing discomforts in patients, conflicting data regarding the safety of sedation among the elderly population exist. This prospective study aimed to compare the quality of recovery (QoR) from gastrointestinal endoscopy performed under sedation between elderly and younger patients. METHODS: We included 177 patients aged 40-64 (group 1, n = 66), 65-79 (group 2, n = 76), and ≥80 (group 3, n = 35) years. QoR was assessed 1 day after the procedure using the quality of recovery 15 (QoR-15) questionnaire, which is a 15-item questionnaire with scores ranging from 0 to 150. Patient demographic, procedural, and sedation data were collected, and neurocognitive function was assessed before and a day after sedation. RESULTS: Groups 1 and 3 differed according to the Mini-Cog test and 3-word memory test performed before the procedure (p < 0.001). QoR-15 scores between groups were not different (139 ± 19 group 1, 141 ± 17 group 2, and 147 ± 26 group 3; p > 0.05). Patients in groups 3 and 2 were administered lower doses of propofol and midazolam than those in group 1. The incidence of oxygen desaturation (SaO2 <90% for >30 s) was lower in groups 1 and 2 than in group 3 (p = 0.01). CONCLUSIONS: As indicated by the QoR-15 questionnaire, the QoR from sedation was not significantly different between the study groups.

Simulation training results in performance retention for the management of airway fires: A prospective observational study.

Given the severity of the consequences of operating room fires, it is recommended that every anaesthesiologist master fire safety protocols and periodically participate in operating room fire drills. The aim of the present study was to evaluate skill retention one year after an airway fire training programme. Anaesthesiology residents were evaluated using an airway fire simulation-based scenario one year after an educational programme that included a one-h long problem-based learning session, a simulation-based airway fire drill with debriefing, and a formal group discussion. The same simulation scenario was used for both the initial training and the one-year assessment. Thirty-eight anaesthesiology residents participated as pairs in the initial training programme. Of these, 36 participated in the evaluation a year later. Performance after one year was better than performance during the initial simulation. Time to removal of tracheal tube was 7.0 (4.0-12.8) s (median (interquartile range)) at the one-year assessment compared with 22.0 (18.5-52.5) s at the time of initial training (P < 0.001). Performance improvement was also demonstrated by a higher incidence of performance of crucial action items (cessation of airway gases, removal of sponges and pouring of saline), as well as shorter duration of time necessary to perform these tasks. After controlling the fire, the time to re-establish ventilation by bag-mask ventilation or intubation was shorter at one year: 18.0 (11.0-29.0 ) s, compared with initial training 54.0 s (36.2-69.8) s (P = 0.001). We conclude that skills are effectively retained for a year after an airway fire management training session.

Respiratory complications during recovery from gastrointestinal endoscopies performed by gastroenterologists under moderate sedation.

BACKGROUND/AIMS: Data on the incidence of adverse respiratory events during recovery from gastrointestinal endoscopy are limited. The aim of this study was to investigate the incidence of these complications. METHODS: In this retrospective cohort study, data were obtained from the electronic records of 657 consecutive patients, who underwent gastroenterological procedures under sedation. RESULTS: Pulse oximetry oxygen saturation (SpO2) <90% for <60 seconds occurred in 82 patients (12.5%) and in 11 patients (1.7%), SpO2 of <90% for >60 seconds occurred in 79 patients (12.0%) and in 11 patients (1.7%), and SpO2 <75% occurred in four patients (0.6%) and in no patients during the procedure and recovery period, respectively. No major complications were noted. The occurrence of desaturation during recovery was correlated with desaturation during the procedure (p<0.001). American Society of Anesthesiologists score (odds ratio [OR], 1.867; 95% confidence interval [CI], 1.008-3.458), ischemic heart disease (OR, 1.815; 95% CI, 0.649-5.080), hypertension (OR, 1.289; 95% CI, 0.472-3.516), and diabetes mellitus (OR, 2.406; 95% CI, 0.950-6.095) increased the occurrence of desaturation during recovery. CONCLUSION: We found no major complications during recovery after balanced propofol-based sedation administered by a gastroenterologist-nurse team. Patients with the identified risk predictors must be monitored carefully.

Towards interpretable, medically grounded, EMR-based risk prediction models.

Machine-learning based risk prediction models have the potential to improve patient outcomes by assessing risk more accurately than clinicians. Significant additional value lies in these models providing feedback about the factors that amplify an individual patient's risk. Identification of risk factors enables more informed decisions on interventions to mitigate or ameliorate modifiable factors. For these reasons, risk prediction models must be explainable and grounded on medical knowledge. Current machine learning-based risk prediction models are frequently 'black-box' models whose inner workings cannot be understood easily, making it difficult to define risk drivers. Since machine learning models follow patterns in the data rather than looking for medically relevant relationships, possible risk factors identified by these models do not necessarily translate into actionable insights for clinicians. Here, we use the example of risk assessment for postoperative complications to demonstrate how explainable and medically grounded risk prediction models can be developed. Pre- and postoperative risk prediction models are trained based on clinically relevant inputs extracted from electronic medical record data. We show that these models have similar predictive performance as models that incorporate a wider range of inputs and explain the models' decision-making process by visualizing how different model inputs and their values affect the models' predictions.

The safety and efficacy of a nurse-led sedation service using Chloral Hydrate for auditory brainstem response testing.

BACKGROUND: There is a growing number of pediatric procedures requiring sedation outside the operating room. Among these are auditory brainstem response (ABR) tests, the gold standard for objective hearing evaluation in infants and toddlers. Recently, a nurse-led pediatric sedation service based on a structured protocol has been developed for ABR testing. OBJECTIVES: To retrospectively analyze the safety and efficacy of the pediatric nurse-led sedation protocol (PNLSP) in a tertiary medical center using Chloral Hydrate (CH) in children undergoing ABR testing. METHODS: Data from medical charts of children who underwent sedation for ABR testing between January 2014 and December 2017, were retrieved. Analysis of sedation success/failure rates, sleep induction time (SIT), sleep duration time (SDT), and adverse events (AE), was performed. FINDINGS: 1348 children with a mean age of 13.4 months (range 3-42 months), classified by the American Society of Anesthesiologists Physical Status Classification System (ASA score) 1-3, were included in the analysis. All children received a fixed dose of 75 mg / kg CH orally or rectally. Sedation success rate was 98.7% and enabled completion of ABR testing. Failure to sedate was evident in 17 children (1.3%), all classified as ASA score 1-2. Median SIT and SDT were 25 and 100 min, respectively. Mild AE occurred in 9 children (0.67%), none of which required further intervention. CONCLUSIONS: Findings support the use of a structured PNLSP using CH as safe and efficient. The suggested protocol is an effective alternative for general anesthesia (GA) for ABR testing in healthy young children.

Influence of anesthesia on hemodynamic assessment of mitral stenosis severity.

BACKGROUND: The treatment of choice for severe rheumatic mitral stenosis (MS) is balloon mitral valvuloplasty (BMV). Assessment of MS severity is usually performed by echocardiography. Before performing BMV, invasive hemodynamic assessment is also performed. The effect of anesthesia on the invasive assessment of MS severity has not been studied. The purpose of the present study was to assess changes in invasive hemodynamic measurement of MS severity before and after induction of general anesthesia. METHODS: The medical files of 22 patients who underwent BMV between 2014 and 2020 were reviewed. Medical history, laboratory, echocardiographic and invasive measurements were collected. Anesthesia induction was performed with etomidate or propofol. Pre-procedural echocardiographic measurements of valve area using pressure half time, and continuity correlated well with invasive measurements using the Gorlin formula. RESULTS: After induction of anesthesia the mean mitral valve gradient dropped by 2.4 mmHg (p = 0.153) and calculated mitral valve area (MVA) increased by 0.2 cm2 (p = 0.011). A wide variability in individual response was observed. While a drop in gradient was noted in 14 patients, it increased in 7. Gorlin derived MVA rose in most patients but dropped in 4. Assuming a calculated MVA of 1.5 cm2 and below to define clinically significant MS, 4 patients with pre-induction MVA of 1.5 cm2 or below had calculated MVA above 1.5 cm2 after induction. CONCLUSIONS: The impact of general anesthesia on the hemodynamic assessment of MS is heterogeneous and may lead to misclassification of MS severity.

Peripartum anesthetic management of women with SARS-CoV-2 infection in eight medical centers across three European countries: prospective cohort observation study.

OBJECTIVE: Several reports of obstetric anesthesia management have been published since the onset of the COVID-19 pandemic. We aimed to collect high-quality broad and detailed data from different university medical centers in several European Society of Anesthesiologist countries. METHODS: This prospective observational survey was performed in eight medical centers in Spain, Israel and Portugal from 1st April to 31st July 2020. Institutional review board approval was received at each participating center. Inclusion criteria: all women with a positive test for COVID-19. Retrieved data included maternal, delivery, anesthetic, postpartum details, and neonatal outcomes. Descriptive data are presented, and outcomes were compared for women with versus without respiratory signs and symptoms. RESULTS: Women with respiratory symptoms (20/12.1%) had significantly higher mean (standard deviation) temperature (37.2 °C (0.8) versus 36.8 °C (0.6)), were older (34.1 (6.7) years versus 30.5 (6.6)) and had higher body mass index kg m-2 - (29.5 (7.5) versus 28.2 (5.1)). Women with respiratory symptoms delivered at a significantly earlier gestational age (50% < 37 weeks) with a 65% cesarean delivery rate (versus 22.1% in the group without respiratory symptoms) and 5-fold increased rate of emergency cesarean delivery, 30% performed under general anesthesia. A higher rate of intrauterine fetal death (3%) was observed than expected from the literature (0.2-0.3%) in developed countries. There was no evidence of viral vertical transmission. CONCLUSION: Well-functioning neuraxial analgesia should be available to manage laboring women with respiratory symptoms, as there is a higher frequency of emergency cesarean delivery. We report a higher rate of undiagnosed parturient and intrauterine fetal death.

[ETHICAL CHALLENGES IN TREATING CRITICAL CORONAVIRUS PATIENTS: EXPERIENCE FROM THE SHEBA MEDICAL CENTER ON THE FIRST COVID-19 PANDEMIC OUTBREAK].

INTRODUCTION: As the coronavirus pandemic emerged in late 2019, a task force was founded in the Sheba Medical Center and began preparing for the arrival of the pandemic to Israel. Several wards were put in charge of isolated COVID-19 patients. A new intensive care unit was formed for the most critical COVID-19 patients, requiring mechanical ventilation and multi-organ treatment. The Corona ICU began operating in March 2020, with a multi-disciplinary team, gathered from ICU units, an internal medicine ward, an anesthesiology department, social workers and psychologists. Simultaneously, the routine medical center functions in non-corona sections were maintained, as much as possible. The coronavirus pandemic entails challenges of many aspects: an unfamiliar pathogen causing an unknown illness, a necessity for social distancing, ambiguity regarding the risk factors for contamination and illness severity, and medical crews put at risk. Consequently, the pandemic involves ethical, social, economic and moral aspects, affecting the medical crew members and system, the patients and their families, and our society as a whole. In this article we review our joint experience in the Sheba Medical Center Corona ICU, of the medical, ethical and moral dilemmas that emerged from the first COVID-19 wave.

Can Quetiapine Prolong the Antidepressant Effect of Ketamine?: A 5-Year Follow-up Study.

PURPOSE: Ketamine, a noncompetitive, high-affinity antagonist of the N-methyl-d-aspartate-type glutamate receptor, has a rapid effect in patients with treatment-resistant disorder, but many patients who respond to intravenous ketamine relapse within several days. The objective of this study was to examine the long-term outcome of patients' mood 5 years after ketamine treatment. METHODS: Sixteen electroconvulsive therapy referrals received at least 1 intravenous ketamine treatment in addition to their stable antidepressant medications. Depression was evaluated using the Inventory of Depressive Symptomatology-Clinician-Rated, Hamilton Rating Scales for Depression, and Montgomery-Åsberg Depression Rating Scale. Anxiety was measured using the Hamilton Rating Scale. RESULTS: Of 16 patients treated, 6 achieved complete remission, 3 partially responded, and 7 did not respond. At baseline, all patients were treated with antidepressants, 14 patients were also treated with neuroleptics, of whom 5 patients were treated with quetiapine. The time to relapse in the 5 patients taking quetiapine was significantly longer than in patients who were taking other neuroleptics (965.83 ± 824.68 vs 80.5 ± 114.3, Z = 7.001, P = 0.0001). At the 5-year follow-up, 3 of the patients taking quetiapine maintained their remission. Overall levels of depression and anxiety at all times were improved in comparison to baseline. CONCLUSIONS: Our follow-up results suggest that the combination of quetiapine and ketamine can prolong time to relapse after ketamine treatment in patients with treatment-resistant disorder.

Anesthesia in Parturients Presenting with Marfan Syndrome.

BACKGROUND: Pregnant women with Marfan syndrome (MS) have a high risk of aortic dissection around delivery and their optimal management requires a multi-disciplinary approach, including proper cardio-obstetric care and adequate pain management during labor, which may be difficult due to the high prevalence of dural ectasia (DE) in these patients. OBJECTIVES: To evaluate the multidisciplinary management of MS patients during labor. METHODS: Nineteen pregnant women (31 pregnancies) with MS were followed by a multi-disciplinary team (cardiologist, obstetrician, anesthesiologist) prior to delivery. RESULTS: Two patients had kyphoscoliosis; none had previous spine surgery nor complaints compatible with DE. In eight pregnancies (7 patients), aortic root diameter (ARd) before pregnancy was 40 to 46 mm. In this high-risk group, one patient underwent elective termination, two underwent an urgent cesarean section (CS) under general anesthesia, and five had elective CS; two under general anesthesia (GA), and three under spinal anesthesia. In 23 pregnancies (12 patients), ARd was < 40 mm. In this non-high-risk group three pregnancies (1 patient) were electively terminated. Of the remaining 20 deliveries (11 patients), 14 were vaginal deliveries, 9 with epidural analgesia and 5 without. Six patients had a CS; four under GA and two2 under spinal anesthesia. There were no epidural placement failures and no failed responses. There were 2 cases of aortic dissection, unrelated to the anesthetic management. CONCLUSIONS: The optimal anesthetic strategy during labor in MS patients should be decided by a multi-disciplinary team. Anesthetic complications due to DE were not encountered during neuraxial block.

Passive Leg Raising After Left Ventricular Assist Device Implantation.

Left ventricular assist device (LVAD) implantation is a common procedure in patients with end-stage heart failure. Although optimal fluid management is essential for acceptable postoperative treatment, it is critical to identify which patients will benefit from fluid administration. Passive leg raising (PLR) is a validated dynamic method that predicts fluid responsiveness in patients with heart failure by inducing a transient increase in cardiac preload. We performed a prospective study on 20 consecutive patients who underwent PLR maneuvers after LVAD implantation. Left ventricular assist device flow, end-tidal carbon dioxide, central venous pressure (CVP), and mean arterial pressure (MAP) were measured before and after PLR. Passive leg raising responsiveness was defined as at least a 15% increase in LVAD flow: (11 were responders and 9 nonresponders). Of the responders, 7 had right ventricular dysfunction (≥3). Passive leg raising responsiveness was associated with an increase of 19% in the LVAD flow, the mean CVP was raised from 11.3 to 14.4 mm Hg and the MAP from 82.6 to 86.7 mm Hg. After PLR, end-tidal carbon dioxide was increased by 4.6 mm Hg in the responders and 1.1 mm Hg in the nonresponders. The PLR maneuver is a noninvasive and easy to perform method that uses LVAD flow to assess fluid responsiveness in patients with heart failure after LVAD implantation.

Evaluation of Miniature Dynamic Light Scattering Technology for the Assessment of Hemodynamic Status During Graded Hemorrhage and Retransfusion in Pigs.

BACKGROUND: Hemorrhagic shock with occult hypoperfusion is a key challenge to prehospital staff during triage and transfer of patients, especially during mass casualty incidents. Recent advances in Dynamic Light Scattering (DLS), and miniaturization of this technology, has resulted in noninvasive sensors capable of continuously monitoring tissue perfusion. This study evaluated the ability of miniature DLS (mDLS) sensors to assess hemodynamic status in a porcine model of hemorrhage. METHODS: Following ethics committee approval, anesthetized and ventilated pigs underwent graded hemorrhage and then retransfusion. Standard vital signs were monitored in conjunction with a thermodilution cardiac output (CO), central venous pressure (CVP), and arterial blood gases. The mDLS sensor was attached to each animal's leg and all monitoring measurements were taken 5 minutes after completion of each period of hemorrhage and retransfusion to allow equilibration. RESULTS: All measured parameters changed during bleeding and retransfusion. During bleeding; p value were 0.011 for heart rate, 0.07 for CVP, <0.001 for both mean arterial pressure, and mDLS. During retransfusion; p values were 0.023 for heart rate, 0.008 for CVP, and <0.001 for both mean arterial pressure and mDLS. Pearson correlation between changes in mDLS and CO demonstrated r value of 0.917 during hemorrhage and 0.965 during retransfusion. Changes in hemoglobin were not statistically significant during bleeding (p = 0.331) but were during retransfusion (p = 0.0001). Changes of bicarbonate, base excess, and lactate were found to be statistically significant during both phases of the experiment (p = 0.001). CONCLUSIONS: In an animal model of hemorrhagic shock, the mDLS sensor strongly correlates with traditional measures of CO. This initial assessment supports further investigation of this technology in human studies.

Melatonin premedication improves quality of recovery following bariatric surgery - a double blind placebo controlled prospective study.

BACKGROUND: Melatonin has hypnotic, sedative, analgesic, anti-inflammatory, and antioxidant properties, and is a widely used sleep agent. OBJECTIVES: Our aim was to evaluate the effect of melatonin premedication on postoperative recovery in patients undergoing bariatric surgery. SETTING: University Hospital, Israel. METHODS: Patients undergoing bariatric surgery were randomized to receive either 5 mg melatonin (M group) or placebo (P group) once on the night before surgery and again 2 hours before surgery. Quality of recovery was assessed using the QoR-15, a 15 item questionnaire on quality of recovery after surgery and anesthesia, regarding emotional state, physical comfort, psychological support, pain, and physical independence. A maximal score of 140 suggested good recovery (1 question was omitted due to irrelevance). The patients answered the questionnaire in the preanesthesia clinic, on admission to the operating room, and on the first postoperative day. RESULTS: A total of 44 patients completed the study. There was no statistical difference between M and P groups in the mean QoR-15 scores obtained before the surgery. Mean postoperative QoR-15 score was higher in the M group compared with the P group (118.3±12.9 versus 107.8±18.7, respectively; P<.01). Scores were also higher in the M group regarding pain (P<.05) and quality of sleep (P< .05). CONCLUSIONS: Use of melatonin premedication improved the quality of recovery 1 day after bariatric surgery as measured by the QoR-15, specifically the quality of sleep and pain levels. Melatonin may serve as a premedication, especially when other options, like benzodiazepines are not recommended.

Thromboelastography during coronary artery bypass grafting surgery of severe hemophilia A patient - the effect of heparin and protamine on factor VIII activity.

: Coronary artery bypass grafting surgery (CABG) in hemophilia patients is challenging. Thromboelastography (TEG) is useful to assess hemostasis perioperatively. A patient with severe hemophilia A underwent CABG with TEG studies. After factor VIII (FVIII) bolus dose, TEG was normalized. Following 'on-pump' heparinization, protamine administration revealed prolonged TEG-R and TEG-R with heparinase confirming it, whereas the activated clotting time was normal, suggesting low FVIII activity rather than excess of heparin. Another FVIII bolus yielded complete normalization of all TEG parameters. Data are compatible with in-vitro assays performed in our laboratory, showing that both heparin and protamine may impair measurable FVIII activity. The rational use of TEG measurements enabled more accurate hemostatic therapy application with regard to FVIII, heparin and protamine administration. Adopting this approach may lead to a better therapy tailoring for hemophilia patients undergoing CABG surgery.

"See One, Sim One, Do One"- A National Pre-Internship Boot-Camp to Ensure a Safer "Student to Doctor" Transition.

INTRODUCTION: The transition for being a medical student to a full functioning intern is accompanied by considerable stress and sense of unpreparedness. Simulation based workshops were previously reported to be effective in improving the readiness of interns and residents to their daily needed skills but only few programs were implemented on a large scale. METHODS: A nationally endorsed and mandated pre-internship simulation based workshop is reported. We hypothesized that this intervention will have a meaningful and sustained impact on trainees' perception of their readiness to internship with regard to patient safety and quality of care skills. Main outcome measure was the workshop's contribution to professional training in general and to critical skills and error prevention in particular, as perceived by participants. RESULTS: Between 2004 and 2011, 85 workshops were conducted for a total of 4,172 trainees. Eight-hundred and six of the 2,700 participants approached by e-mail, returned feedback evaluation forms, which were analyzed. Eighty five percent of trainees perceived the workshop as an essential component of their professional training, and 87% agreed it should be mandatory. These ratings peaked during internship and were generally sustained 3 years following the workshop. Contribution to emergency care skills was especially highly ranked (83%). CONCLUSION: Implementation of a mandatory, simulation-based, pre-internship workshop on a national scale made a significant perceived impact on interns and residents. The sustained impact should encourage adopting this approach to facilitate the student to doctor transition.

A Simple Diagnostic Test to Confirm Correct Placement of Dysfunctional Central Venous Catheters Before Chemotherapy in Children.

BACKGROUND: In children undergoing intravenous chemotherapy, partial dysfunction of the central venous catheter (CVC) is common. Fluids can be infused into the catheter; however, blood cannot be aspirated. In those situations, chemotherapy is withheld and a catheter investigation is performed. Usually, a radiographic study with contrast media or therapy with thrombolytic drugs followed by rechecking for blood return is undertaken. AIM: To evaluate if a previously described method using dilute sodium bicarbonate injection and the resultant rise in measured end-tidal carbon dioxide tracing can confirm correct intravascular placement of a dysfunctional CVC in children at the bedside. PATIENTS: Cohort group of 22 children scheduled for chemotherapy with partial dysfunction of a CVC in a tertiary hematology-oncology care facility. RESULTS: All children with a partial dysfunctional CVC that was proven to be intravascular after venogram or thrombolytic therapy had a distinct and predictable increase in end-tidal carbon dioxide response to injected bicarbonate. CONCLUSION: Injection of 1 mL/kg (maximum 20 mL) of 4.2% dilute sodium bicarbonate is a quick, simple, bedside test allowing confirmation of intravascular location of dysfunctional CVC.

A simple diagnostic test to confirm correct intravascular placement of peripheral catheters in order to avoid extravasation.

BACKGROUND: Intravenous catheters are ubiquitous among modern medical management of patients, yet misplaced or tissued cannulas can result in serious iatrogenic injury due to infiltration or extravasation of injectate. Prevention is difficult, and currently few reliable tests exist to confirm intravascular placement of catheters in awake spontaneously breathing patients. METHODS: Twenty conscious spontaneously breathing healthy volunteers were injected with 50 mL normal saline and 50 mL 4.2%, or 50 mL 2.1%, or 20 mL 4.2% sodium bicarbonate in a random order. A blinded anesthetist observed continuous sampling of exhaled carbon dioxide and was asked to differentiate between the sodium bicarbonate and saline injections. Peak increase in measured exhaled carbon dioxide was also calculated. RESULTS: Exhaled carbon dioxide increased significantly in participants injected with intravenous sodium bicarbonate. Mean peak increase was 7.4 mm Hg (±2.1 mm Hg) for 50 mL 4.2% sodium bicarbonate, 4.7 mm Hg (±2.5 mm Hg) for 20 mL 4.2% sodium bicarbonate, and 3.5 mm Hg (±1. 8 mm Hg) for 50 mL 2.1% sodium bicarbonate. The blinded observer correctly identified the injection as sodium bicarbonate or normal saline in every instance. DISCUSSION: Intravenous injection of dilute sodium bicarbonate with exhaled carbon dioxide monitoring reliably confirms correct intravascular placement of a catheter. A transient increase of exhaled carbon dioxide by 10% or more is an objective and reliable confirmation of intravascular location of the catheter. We recommend using 20 mL of 4.2% sodium bicarbonate to minimize the mEq dose of sodium bicarbonate required.

A simple diagnostic test to confirm correct placement of intravenous catheters before chemotherapy.

PURPOSE: To determine the feasibility and effectiveness of using a single injection of diluted sodium bicarbonate, while monitoring exhaled carbon dioxide changes, to reliably confirm correct placement of intravenous (IV) catheters. METHODS: The study was conducted in the oncology day care clinic at a tertiary care center and included a selected group of patients with various oncological conditions who required IV chemotherapy. In each patient a newly inserted peripheral IV catheter or newly accessed central line was deemed positively intravascular if they had good blood return or most probably intravascular if there was no blood return but they flushed easily. This clinical diagnosis of correct positioning, was correlated with the results of a single injection of dilute sodium on the exhaled carbon dioxide, and with the ability of a blinded observer to report whether sodium bicarbonate or saline was injected. RESULTS: A total of 67 patients were enrolled in the study; 56 had positively intravascular IV catheter while 11 had most probably intravascular IV catheter. A single injection of 20 mL 4.2% sodium bicarbonate had a positive and clinically detectable response that was diagnosed with high sensitivity and specificity. CONCLUSIONS: IV injection of 20 mL of 4.2% sodium bicarbonate with exhaled carbon dioxide monitoring can be used to reliably confirm correct intravascular placement of a catheter intended to be used for chemotherapy.