Normative Transesophageal Echocardiographic Values of Cardiac Structures in the Indian Population-Indian Normative TEE Measurements (INTEEM) Study.

OBJECTIVES: Information on normative reference values for cardiac structures is critical for the accurate application of echocardiography for guiding clinical decision-making. Many studies using transthoracic echocardiography (TTE) have shown that Indians have smaller diameters of various cardiac structures. There are no normative studies for transesophageal echocardiography (TEE). The authors observed dimensions of various cardiac structures in healthy Indian patients under general anesthesia using TEE and compared them with existing guidelines from non-Indian data. DESIGN: The Indian Normative TEE Measurements study was a multicenter, prospective observational study conducted in India. SETTING: Operating rooms for noncardiac surgeries in tertiary care-level hospitals. PARTICIPANTS: Adult patients undergoing noncardiac surgery who were free from any cardiac, respiratory, and renal diseases and had no contraindications for TEE. INTERVENTIONS: After inducing general anesthesia and achieving stable hemodynamic conditions, a comprehensive TEE examination was performed and various measurements were made. MEASUREMENTS AND MAIN RESULTS: For each of the 83 patients undergoing noncardiac surgery, 39 various measurements for left ventricle, right ventricle, both atria, and all valves were made. This included diameters and functional parameters. They were analyzed in a vendor-neutral software off-line. The absolute values of many of the measurements were higher in men, but when indexed to body surface area (BSA) they were similar in both sexes. The values were lower than most of the Western data but matched previous Indian studies using TTE. CONCLUSIONS: The authors present normative values of various echocardiographic parameters using TEE. Because of its variations, it is recommended to use India-specific data to make decisions in Indian patients. It may be prudent to use BSA-indexed values during decision-making.

Perioperative temperature management: a survey of 6 Asia-Pacific countries.

BACKGROUND: Anesthesia leads to impairments in central and peripheral thermoregulatory responses. Inadvertent perioperative hypothermia is hence a common perioperative complication, and is associated with coagulopathy, increased surgical site infection, delayed drug metabolism, prolonged recovery, and shivering. However, surveys across the world have shown poor compliance to perioperative temperature management guidelines. Therefore, we evaluated the prevalent practices and attitudes to perioperative temperature management in the Asia-Pacific region, and determined the individual and institutional factors that lead to noncompliance. METHODS: A 40-question anonymous online questionnaire was distributed to anesthesiologists and anesthesia trainees in six countries in the Asia-Pacific (Singapore, Malaysia, Philippines, Thailand, India and South Korea). Participants were polled about their current practices in patient warming and temperature measurement across the preoperative, intraoperative and postoperative periods. Questions were also asked regarding various individual and environmental barriers to compliance. RESULTS: In total, 1154 valid survey responses were obtained and analyzed. 279 (24.2%) of respondents prewarm, 508 (44.0%) perform intraoperative active warming, and 486 (42.1%) perform postoperative active warming in the majority of patients. Additionally, 531 (46.0%) measure temperature preoperatively, 767 (67.5%) measure temperature intraoperatively during general anesthesia, and 953 (82.6%) measure temperature postoperatively in the majority of patients. The availability of active warming devices in the operating room (p < 0.001, OR 10.040), absence of financial restriction (p < 0.001, OR 2.817), presence of hospital training courses (p = 0.011, OR 1.428), and presence of a hospital SOP (p < 0.001, OR 1.926) were significantly associated with compliance to intraoperative active warming. CONCLUSIONS: Compliance to international perioperative temperature management guidelines in Asia-Pacific remains poor, especially in small hospitals. Barriers to compliance were limited temperature management equipment, lack of locally-relevant standard operating procedures and training. This may inform international guideline committees on the needs of developing countries, or spur local anesthesiology societies to publish their own national guidelines.

Sympatho-vagal balance, as quantified by ANSindex, predicts post spinal hypotension and vasopressor requirement in parturients undergoing lower segmental cesarean section: a single blinded prospective observational study.

Hypotension subsequent to spinal anesthesia occurs in a significant number of parturients undergoing lower segment caesarian section. Currently available methods to predict the incidence of hypotension, its severity and the outcome are sub-optimal. Many workers have used basal heart rate as one of the predictors. But using this method it is not possible to objectively analyze and predict the extent and severity of hypotension. We used an equipment measuring the level of sympatho-vagal balance, ANSiscope™, which derives these values from computed value of RR interval variability. We made a single measure of the value which was blinded to the patient and the anesthesiologist. We studied one hundred eight patients who underwent lower segment caesarian section under spinal anesthesia and found the variability of preoperative ANSindex (% activity displayed by the equipment) from 9 to 65 %. Higher ANSindex value was significantly associated with post spinal hypotension (p 0.017). A value of 24 % indicated the critical level above which hypotension appeared commonly. The ANSindex value might help anesthesiologist to anticipate and prepare for hypotension that is likely to ensue.

Simultaneous surgical management of malignancy and coronary heart disease.

Coronary heart disease and cancer are the most common causes of mortality across the globe. It has been a dilemma for the surgical team to decide which surgical procedure should be done first when a patient needs surgery for both. This is a single-center retrospective observational study. Six patients who underwent simultaneous coronary artery bypass graft (CABG) and oncological surgeries between January 2018 and July 2021 were included in the study. One patient underwent lung bilobectomy via the same sternotomy incision; one underwent surgery for breast cancer, stomach cancer, and colon cancer; and one patient each of buccal mucosa carcinoma and tongue carcinoma. The median age was 65 years (59-70). Median blood loss was 550 ml (400-800). The median intensive care unit (ICU) stay was 60 h (46-130) and hospital stay was 7.5 days (6-14). The median follow-up of the present study was 31.5 months (6-38). One patient with lung carcinoma developed recurrence after 6 months and the patient is in remission after a follow-up of 32 months. Simultaneous CABG and oncological resection can be performed effectively and safely by an experienced team of cardiothoracic surgeons, surgical oncologists, and anesthetists after good patient selection.

Epidemiology and preventability of hospital-onset bacteremia and fungemia in 2 hospitals in India.

OBJECTIVE: Studies evaluating the incidence, source, and preventability of hospital-onset bacteremia and fungemia (HOB), defined as any positive blood culture obtained after 3 calendar days of hospital admission, are lacking in low- and middle-income countries (LMICs). DESIGN, SETTING, AND PARTICIPANTS: All consecutive blood cultures performed for 6 months during 2020-2021 in 2 hospitals in India were reviewed to assess HOB and National Healthcare Safety Network (NHSN) reportable central-line-associated bloodstream infection (CLABSI) events. Medical records of a convenience sample of 300 consecutive HOB events were retrospectively reviewed to determine source and preventability. Univariate and multivariable logistic regression analyses were performed to identify factors associated with HOB preventability. RESULTS: Among 6,733 blood cultures obtained from 3,558 hospitalized patients, there were 409 and 59 unique HOB and NHSN-reportable CLABSI events, respectively. CLABSIs accounted for 59 (14%) of 409 HOB events. There was a moderate but non-significant correlation (r = 0.51; P = .070) between HOB and CLABSI rates. Among 300 reviewed HOB cases, CLABSIs were identified as source in only 38 (13%). Although 157 (52%) of all 300 HOB cases were potentially preventable, CLABSIs accounted for only 22 (14%) of these 157 preventable HOB events. In multivariable analysis, neutropenia, and sepsis as an indication for blood culture were associated with decreased odds of HOB preventability, whereas hospital stay ≥7 days and presence of a urinary catheter were associated with increased likelihood of preventability. CONCLUSIONS: HOB may have utility as a healthcare-associated infection metric in LMIC settings because it captures preventable bloodstream infections beyond NHSN-reportable CLABSIs.

Outcomes of in-hospital, out of intensive care and operation theatre cardiac arrests in a tertiary referral hospital.

OBJECTIVE: Cardiac arrest in the hospital wards may not receive as much attention as it does in the operation theatre and intensive care unit (ICU). The experience and the qualifications of personnel in the ward may not be comparable to those in the other vital areas of the hospital. The outcome of cardiac arrest from the ward areas is a reasonable surrogate of training of the ward nurses and technicians in cardiopulmonary resuscitation. We conducted an audit to assess the issues surrounding the resuscitation of cardiac arrest in areas other than operation theatre and ICU in a tertiary referral hospital. AIMS OF THE AUDIT: To assess the outcomes of cardiac arrest in a tertiary referral hospital. Areas such as wards, dialysis room and emergency room were considered for the audit. METHODS: This is a retrospective observational audit of the case records of all the adult patients who were resuscitated from 'code blue'. Data for 2 years from 2007 was analysed by a research fellow unconnected with the resuscitations. RESULTS: Twenty-two thousand three hundred and forty-four patients were admitted as in-patients to the hospital during the 2 years, starting May 2007 through May 2009. One hundred code blue calls were received during this time. Twenty-two of the total calls received were false. Among the 78 confirmed cardiac arrests 69 occurred in the wards, 2 in emergency room, 1 in cardiac catheterisation laboratory and 3 in dialysis room. Twenty-eight patients were declared dead after unsuccessful cardiopulmonary resuscitation. Among the 50 who were resuscitated with a return of spontaneous rhythm 26 died. Twenty-four patients were discharged (survival rate of 30%). The survival decreased significantly as the age progressed beyond 60. The resuscitation rates were better in day shifts in contrast to the night. Higher survival was noted in patients who received resuscitation in less than a minute. CONCLUSION: A overall survival to discharge rate of 30% was noted in this audit. Higher survival rates might be attributable to high rate and degree of training at the time of their employment, which was repeated at yearly interval.

Hemoadsorption in Complex Cardiac Surgery-A Single Center Experience.

(1) Background: Cardiac surgery may evoke a generalized inflammatory response, typically magnified in complex, combined, redo, and emergency procedures with long aortic cross-clamp times. Various treatment options have been introduced to help regain control over post-cardiac surgery hyper-inflammation, including hemoadsorptive immunomodulation with CytoSorb®. (2) Methods: We conducted a single-center retrospective observational study of patients undergoing complex cardiac surgery. Patients intra-operatively treated with CytoSorb® were compared to a control group. The primary outcome was the change in the vasoactive-inotropic score (VIS) from pre-operatively to post-operatively. (3) Results: A total of 52 patients were included in the analysis, where 23 were treated with CytoSorb® (CS) and 29 without (controls). The mean VIS increase from pre-operative to post-operative values was significantly lower in the CS group compared to the control group (3.5 vs. 5.5, respectively, p = 0.05). In-hospital mortality in the control group was 20.7% (6 patients) and 9.1% (2 patients) in the CS group (p = 0.26). Lactate level changes were comparable, and the median intensive care unit and hospital lengths of stay were similar between groups. (4) Conclusions: Despite notable imbalances between the groups, the signals revealed point toward better hemodynamic stability with CytoSorb® hemoadsorption in complex cardiac surgery and a trend of lower mortality.

Decrease in pulmonary artery pressure after administration of thoracic epidural anesthesia in a patient with Marfan syndrome awaiting aortic valve replacement procedure.

Thoracic epidural anesthesia is an adjunct to general anesthesia in cardiac surgery. Decrease in heart rate and blood pressure are frequently seen beneficial effects. There are several other hemodynamic effects of thoracic epidural anesthesia such as decrease in systemic vascular resistance, cardiac index, left ventricular stroke work index among others. However, the effect of thoracic epidural anesthesia on pulmonary artery pressure (PAP) has not been studied extensively in humans. Thoracic epidural anes-thesia decreased pulmonary artery pressure in experimen-tally induced pulmonary hypertension in animals. The mechanisms involved in such reduction are ill understood. We describe in this report, a significant reduction in PAP in a patient with Marfan's syndrome scheduled to under-go aortic valve replacement. The possible mechanisms of decrease in pulmonary artery pressure in the described case are, decrease in the venous return to the heart, decrease in the systemic vascular resistance, decrease in the right ventric-ular function and finally, improvement in myocardial contraction secondary to all the above. The possibility of Marfan's syndrome contributing to the decrease in PAP appears remote. The authors present this case to generate discussion about the possible mechanisms involved in thoracic epidural anesthesia producing beneficial effects in patients with secondary pulmonary hypertension. Thoracic epidural anesthesia appears to decrease pulmonary artery pressure by a combination of several mechanisms, some unknown to us. This occurrence, if studied and understood well could be put to clinical use in pulmonary hypertensives.

Hospital acquired infection is inversely related to utilization of isopropyl alcohol and tissue paper pulls--a prospective observational study.

INTRODUCTION: Healthcare associated infections not only cause morbidity and mortality, but also drain the resources in the hospitals across the globe. It has been shown repeatedly that practicing hand hygiene is a deterrent to hospital acquired infection. It is essential for the infection control committee and the hospital administrators to have a fair idea of the prevailing hand hygiene practice in the healthcare facility. This is commonly obtained direct observation, self-reporting by healthcare workers and indirect calculation based on hand hygiene disinfectant product usage. AIMS: This study was planned to assess the indirect surrogates of hand hygiene among healthcare workers in an Indian hospital. METHODS: We presumed that the tools used to perform hand hygiene, the alcoholic hand rub and the tissue paper towel may throw light on the prevailing hand hygiene practice. An analysis of the quantity of alcohol hand rub and the number of tissue paper towel usage against the incidence of hospital acquired infection was made. OBSERVATION: The mean incidence of HAI during the period of study was 8.5 +/- 6.7 (range 2 to 27) per month. There was a decrease in the HAI rates with increasing of alcoholic hand rub and tissue paper towels. It was predicted using the regression graphs that if the quantity of alcoholic hand rub usage increased to 2620 Ltrs/ month, the HAI would be '0'. Similarly if 427,0000 tissue paper towel pulls were used, the HAI would be '0'. CONCLUSION: Studying the incidence consumption of the quantity of tissue paper rolls and isopropyl alcohol may be used as a surrogate of hand hygiene practice among healthcare workers.

A career in cardiac anaesthesia in India: The heart of the matter.

Cardiac anaesthesia is a demanding, but fulfilling speciality which challenges the skills, knowledge, professional and personal competence of cardiac anaesthesiologists on a daily basis. This article outlines the brief history of the subspecialty of cardiac anaesthesia in India, its growth and progress over the decades, reasons for choosing it as a career option, variations in practice standards and how the speciality has been affected by the coronavirus 2019 pan?demic.

Weaning mechanical ventilation after off-pump coronary artery bypass graft procedures directed by noninvasive gas measurements.

OBJECTIVE(S): Partial pressure of carbon dioxide and oxygen were transcutaneously measured in adults after off-pump coronary artery bypass (OPCAB) surgery. The clinical use of such measurements and interchangeability with arterial blood gas measurements for weaning patients from postoperative mechanical ventilation were assessed. DESIGN: This was a prospective observational study. SETTING: Tertiary referral heart hospital. PARTICIPANTS: Postoperative OPCAB surgical patients. INTERVENTIONS: Transcutaneous oxygen and carbon dioxide measurements. MEASUREMENTS AND MAIN RESULTS: In this prospective observational study, 32 consecutive adult patients in a tertiary care medical center underwent OPCAB surgery. Noninvasive measurement of respiratory gases was performed during the postoperative period and compared with arterial blood gases. The investigator was blinded to the reports of arterial blood gas studies and weaned patients using a "weaning protocol" based on transcutaneous gas measurement. The number of patients successfully weaned based on transcutaneous measurements and the number of times the weaning process was held up were noted. A total of 212 samples (pairs of arterial and transcutaneous values of oxygen and carbon dioxide) were obtained from 32 patients. Bland-Altman plots and mountain plots were used to analyze the interchangeability of the data. Twenty-five (79%) of the patients were weaned from the ventilator based on transcutaneous gas measurements alone. Transcutaneous carbon dioxide measurements were found to be interchangeable with arterial carbon dioxide during 96% of measurements, versus 79% for oxygen measurements. CONCLUSION: More than three fourths of the patients were weaned from mechanical ventilation and extubated based on transcutaneous gas values alone after OPCAB surgery. The noninvasive transcutaneous carbon dioxide measurement can be used as a surrogate for arterial carbon dioxide measurement to manage postoperative OPCAB patients.

"Rigor mortis" in a live patient.

Rigor mortis is conventionally a postmortem change. Its occurrence suggests that death has occurred at least a few hours ago. The authors report a case of "Rigor Mortis" in a live patient after cardiac surgery. The likely factors that may have predisposed such premortem muscle stiffening in the reported patient are, intense low cardiac output status, use of unusually high dose of inotropic and vasopressor agents and likely sepsis. Such an event may be of importance while determining the time of death in individuals such as described in the report. It may also suggest requirement of careful examination of patients with muscle stiffening prior to declaration of death. This report is being published to point out the likely controversies that might arise out of muscle stiffening, which should not always be termed rigor mortis and/ or postmortem.

Index of consciousness and bispectral index values are interchangeable during normotension and hypotension but not during non pulsatile flow state during cardiac surgical procedures: a prospective study.

OBJECTIVES: Awareness under anesthesia is an avoidable complication during general anesthesia. Anesthetic depth monitors assist anesthesiologists in providing appropriate levels of anesthesia. Index of consciousness monitoring is a recently introduced monitor in the array of anesthesia depth monitors. The objective of this study was to assess the interchangeability of bispectral index, which is already in clinical use and the recently introduced index of consciousness techniques. The other objective was to assess this interchangeability during normotension, hypotension and during pulseless state in patients undergoing coronary artery bypass graft surgery. This study is a prospective observational study, conducted in a tertiary referral hospital. MEASUREMENTS AND MAIN RESULTS: Fifteen cardiac surgical patients undergoing off pump and conventional coronary artery bypass under cardiopulmonary bypass participated in the study. Bispectral index and index of consciousness monitoring were carried out simultaneously during various stages of consciousness, and assessed for interchangeability. Bland Altman plotting and 'mountain plot' were used to assess the interchangeability. Eleven in the cohort underwent off pump and the rest (n = 4) conventional coronary artery bypass surgery under cardiopulmonary bypass. A set of 887 data were obtained during the study period. The data were classified as those obtained during normotension, hypotension and pulseless state during cardiopulmonary bypass. RESULTS: 732 sets of data were obtained during normotension, 84 during hypotension and 71 during cardiopulmonary bypass. Overall interchangeability was good, suggested by low bias (0.96), high precision (0.54), r value of 0.7 and P value of <0.0001. It was found that the data obtained during normotension was also interchangeable, suggested by low bias (0.8), high precision (0.54) and r value of 0.7. The data obtained during hypotension was not as highly interchangeable as during normotension-bias 0.4, precision 1.66 and r value of 0.7. The analysis of value during cardiopulmonary bypass suggested non interchangeability (bias 3.87, precision 3.05, r value 0.3 and P value = 0.0067. CONCLUSIONS: The bispectral index and index of consciousness values may be interchangeable. The interchangeability is better appreciated during normotension and hypotension but not during non pulsatile state of cardiopulmonary bypass.

Routine preoperative doppler ultrasound examination of arterial system in patients undergoing cardiac surgery is beneficial: A retrospective study.

Background: Presence of peripheral vascular disease enhances surgical risk in cardiac surgical patients. Prior knowledge of peripheral arterial disease may help the physician make changes in the monitoring and cardiopulmonary bypass cannulation plans. It is claimed that the incidence of peripheral vascular disease in cardiac surgical patients ranges from 11 to 30%. Aims: This study was conducted to understand the characteristics of peripheral vascular disease and their implication on cardiac surgery. Settings and Design: This was a prospective study undertaken in a tertiary referral hospital. Materials and Methods: All adult patients who underwent cardiac surgery during the period of six months were included. A Doppler examination of the neck, upper limb, abdomen and lower limb was carried out by our inhouse radiologist. The incidence of peripheral vascular disease, the implication on invasive pressure monitoring site and cannulation for cardiopulmonary bypass or intraaortic balloon pump or extracorporeal membrane oxygenation were made note of. Results: During the said period, six hundred twenty eight patients underwent cardiac surgery, of whom five hundred and sixty-one patients who underwent CABG surgery. All these were subjected to Doppler examination. We observed peripheral arterial disease in 105 patients (20%). In general men suffered from PAD more often than women. Monitoring site of invasive arterial pressure, the choice of beating heart surgery, insertion of intraaortic balloon pump, femoral arterial route for cardiopulmonary bypass were some of the decision that were altered. Conclusions: Performing Doppler examination in cardiac surgical patients may yield important data that might prevent complications and support patient safety.

Six-year multicenter study on short-term peripheral venous catheters-related bloodstream infection rates in 204 intensive care units of 57 hospitals in 19 cities of India: International Nosocomial Infection Control Consortium (INICC) findings.

BACKGROUND: Short-term peripheral venous catheters-related bloodstream infections (PVCR-BSIs) rates have not been systematically studied in developing countries, and data on their incidence by number of device-days are not available. METHODS: Prospective, surveillance study on PVCR-BSI conducted from September 1, 2013 to May 31, 2019 in 204 intensive care units (ICUs), members of the International Nosocomial Infection Control Consortium (INICC), from 57 hospitals in 19 cities of India. We applied US INICC definition criteria and reported methods using the INICC Surveillance Online System. RESULTS: We followed 7,513 ICU patients for 296,893 bed-days and 295,795 short term peripheral venous catheter (PVC)-days. We identified 863 PVCR-BSIs, amounting to a rate of 2.91/1,000 PVC-days. Mortality in patients with PVC but without PVCR-BSI was 4.14%, and 11.59% in patients with PVCR-BSI. The length of stay in patients with PVC but without PVCR-BSI was 4.13 days, and 5.9 days in patients with PVCR-BSI. The micro-organism profile showed 68% of gram negative bacteria: Escherichia coli (23%), Klebsiella spp (15%), Pseudomonas aeruginosa (5%), and others. The predominant gram-positive bacteria were Staphylococcus aureus (10%). CONCLUSIONS: PVCR-BSI rates found in our ICUs were much higher than rates published from industrialized countries. Infection prevention programs must be implemented to reduce the incidence of PVCR-BSIs.

Cardiac index value measurement by invasive, semi-invasive and non invasive techniques: a prospective study in postoperative off pump coronary artery bypass surgery patients.

The authors prospectively compared three techniques of continuous cardiac index measurements. They were, invasive Continuous Cardiac Index using thermodilution flow-directed Swan-Ganz pulmonary artery catheters, semi invasive Flotrac-arterial pressure derived cardiac index and the non invasive cardiac index measurement-body impedance plethsmography. The cardiac index measurements were made simultaneously in the postoperative period in 20 patients who underwent elective uncomplicated off pump coronary artery bypass graft. The values were collected once in 5 min over a period of 30-40 min. A set of 140 values were obtained from the cohorts in our study. Inter-changeability of the values of cardiac index was analysed using Bland-Altman and mountain plots. The cardiac index values ranged from 1.6 to 3.6 l/min/m(2). The values obtained were interchangeable. The bias and precision respectively were 0.02 and +/-0.06 for continuous cardiac index and Flotrac, 0.18 and +/-0.08 for Flotrac and body impedance plethysmography and 0.16 and +/-0.08 for continuous cardiac index and body impedance plethysmography. Flotrac appears to be more useful during off pump coronary artery bypass surgery.

Early non invasive detection of hypercarbia in two cardiac surgical patients.

The availability of transcutaneous monitors has provided a means of non invasive assessment of CO(2) tension and a trend of the ventilation status commonly in infants and neonates. The authors describe two cases of hypercapnia diagnosed early in adults by the non invasive transcutaneous measurement of carbon dioxide (tcpCO(2)) using TINA TCM4 in postoperative cardiac surgical patients who were mechanically ventilated. Curiously, this increase in tcpCO(2) levels was associated with a false increase in the tcpO(2) values though no changes in the ventilatory parameters to increase oxygenation were made. The probable mechanism of the increase in tcpO(2) levels with hypercarbia is discussed.

Improvement in accuracy of transcutaneous measurement of oxygen with resumption of spontaneous ventilation in mechanically ventilated patients after off pump coronary artery bypass procedure: a prospective study.

INTRODUCTION: Transcutaneous measurement of gases depends on the degree of skin perfusion. Mechanical ventilation causes alteration in the peripheral perfusion. The aim of this prospective observational study was to assess change in the accuracy of interchangeability of arterial blood gases with those obtained transcutaneously at various phases of mechanical ventilation such as controlled mandatory, synchronized intermittent mandatory, continuous positive airway pressure ventilations, spontaneous breathing trail and spontaneous ventilation after extubation of endotracheal tube. METHODS: Thirty-two adult patients who underwent uncomplicated off pump coronary artery bypass surgery in a tertiary care medical center were subjected to transcutaneous measurements of gases from the sensor placed on the chest during postoperative ventilation. Arterial blood gas analysis was performed at predetermined time intervals and transcutaneous measurements were repeated each of those time. RESULTS: Fifty-four sets of data were obtained during controlled ventilation and fifty during spontaneous. Correlation coefficient for oxygen increased from 0.46 (P = 0.0004) during controlled ventilation to 0.75 (P < 0.0001) during spontaneous. Bland-Altman and mountain plots suggested better inter- changeability of values between arterial blood gas and transcutaneous gas monitoring. The bias for oxygen changed from 21 during controlled ventilation to 25 during spontaneous ventilation and the precision from 7.1 to 6.4. There was no change in the accuracy of transcutaneous carbon dioxide values during either phase of ventilation. CONCLUSION: The accuracy of transcutaneously measured values of oxygen improved significantly during spontaneous ventilation.

Evaluation of Percutaneous Electrical Nerve Stimulation of the Auricle for Relief of Postoperative Pain Following Cesarean Section.

Objective: Percutaneous electrical nerve stimulation is a nonpharmacologic modality of analgesia. This study was conducted to evaluate such a technology (ANSiStim™, DyAnsys Inc., San Mateo, CA) prospectively, in conjunction with standard analgesia per patient demand, for managing postoperative pain following lower-segment cesarean section. Materials and Methods: One hundred parturients were randomized into 2 equal groups (controls and study cases). The latter cohort consisted of parturients for whom nerve stimulation was exerted on the pinna. Pain scores were compared across subjects at corresponding time points with 17 intervals in 48 hours, and, in totality, using estimated area under the curves of numerical scores. Conditional inference analysis was also performed. Results: Ninety-six parturients were finally included. The device was well-tolerated by a majority of parturients. Pain scores were significantly lower in the study group, both at corresponding time intervals and in totality. (H - 15)*(0.74 - H)*(H2 - 17H + 110)/440, where H was the corresponding hour, fit the pain scores in the control group. Controls could be detected at the 11 hour with greater pain scores (≥ 4), whereas smaller scores (≤ 2) at the 42nd hour mostly revealed that electrical stimulation was performed (p < 0.001). Requirements for supplementary analgesics were lower for subjects who were given the electroanalgesia. Conclusions: Neurostimulation via the ANSiStim™ is a safe and reasonably effective ambulatory analgesic adjuvant following abdominal delivery. There are no serious adverse effects.