Pulmonary hypertension is a well-established independent risk factor for perioperative complications after elective non-cardiac surgery. Patients undergoing cardiac surgery are routinely evaluated for the presence of pulmonary hypertension in the preoperative period. Better monitoring in the postoperative critical care setting leads to more efficient management of potential complications. Data among patients with pulmonary hypertension undergoing elective non-cardiac surgery are scant. Moreover, the condition may be unidentified at the time of surgery. Also, monitoring after non-cardiac surgery can be very limited in the PACU setting, as opposed to the critical care setting. All these factors can result in a higher postoperative complication rate and poor outcomes.

Arterial blood pressure is one of the vital signs monitored mandatory in anaesthetised patients. Even short episodes of intraoperative hypotension are associated with increased risk for postoperative organ dysfunction such as acute kidney injury and myocardial injury. Since there is little evidence whether higher alarm thresholds in patient monitors can help prevent intraoperative hypotension, we analysed the blood pressure data before (group 1) and after (group 2) the implementation of altered hypotension alarm settings. The study was conducted as a retrospective observational cohort study in a large surgical centre with 32 operating theatres. Alarm thresholds for hypotension alarm for mean arterial pressure (MAP) were altered from 60 (before) to 65 mmHg for invasive measurement and 70 mmHg for noninvasive measurement. Blood pressure data from electronic anaesthesia records of 4222 patients (1982 and 2240 in group 1 and 2, respectively) with 406,623 blood pressure values undergoing noncardiac surgery were included. We analysed (A) the proportion of blood pressure measurements below the threshold among all measurements by quasi-binomial regression and (B) whether at least one blood pressure measurement below the threshold occurred by logistic regression. Hypotension was defined as MAP < 65 mmHg. There was no significant difference in overall proportions of hypotensive episodes for mean arterial pressure before and after the adjustment of alarm settings (mean proportion of values below 65 mmHg were 6.05% in group 1 and 5.99% in group 2). The risk of ever experiencing a hypotensive episode during anaesthesia was significantly lower in group 2 with an odds ratio of 0.84 (p = 0.029). In conclusion, higher alarm thresholds do not generally lead to less hypotensive episodes perioperatively. There was a slight but significant reduction of the occurrence of intraoperative hypotension in the presence of higher thresholds for blood pressure alarms. However, this reduction only seems to be present in patients with very few hypotensive episodes.

Children born with esophageal atresia experience long-term neurodevelopmental deficits, with unknown origin.
To find associations between perioperative variables during primary esophageal atresia repair and motor function at age 5 years.
This ambidirectional cohort study included children born with esophageal atresia who consecutively had been operated on in the Erasmus MC-Sophia Children\'s Hospital, University Medical Center, Rotterdam, from January 2007 through June 2013. The perioperative data of this cohort were collected retrospectively; the motor function data prospectively.
After exclusion of patients with syndromal congenital diseases (n = 8) and lost to follow-up (n = 10), the data of 53 children were included. The mean (SD) total motor function impairment z-score at 5 years of age was -0.66 (0.99), significantly below normal (p < .001). In multivariable linear regression analysis, number of postoperative days endotracheal intubation (B = -0.211, 95% CI: -0.389 to -0.033, p = .021) was negatively associated with motor outcome, whereas high blood pressure (B = 0.022, 95% CI 0.001 to 0.042, p = .038) was positively associated. Preoperative nasal oxygen supplementation versus room air (B = 0.706, 95% CI: 0.132 to 1.280, p = .016) was positively associated with motor outcome, which we cannot explain.
Motor function in 5-year-old esophageal atresia patients was impaired and negatively associated with the number of postoperative days of endotracheal intubation and positively associated with high blood pressure. Prospective studies with critical perioperative monitoring and monitoring during stay at the intensive care unit are recommended.

OBJECTIVE: This study was performed to depict the patterns of change in the perioperative hemoglobin (Hb) concentration and hematocrit (Hct) and to identify the optimal timing of Hb and Hct measurement in patients undergoing total knee arthroplasty (TKA).
METHODS: This prospective observational study involved 302 consecutive patients who underwent TKA. The patients were kept in hospital for 1 full week postoperatively. Hb and Hct measurements were performed preoperatively and on days 1 to 7 postoperatively and then during clinic visits at 1, 3, and 6 months postoperatively.
RESULTS: The Hb concentration and Hct decreased during the first few days postoperatively and reached a nadir on postoperative day 4 and 3, respectively; they then recovered in the following days. Significant differences in the Hb concentration and Hct were detected between the preoperative period and day 1, between days 1 and 2, between days 2 and 3, between day 7 and 1 month, and between 1 and 3 months. A significant difference in the Hct was also detected between 3 and 6 months.
CONCLUSIONS: The optimal timing of Hb and Hct measurement is on postoperative day 3 or 4. This timing accurately reflects ongoing hidden blood loss to better guide blood transfusions.

BACKGROUND: The prevalence of nuisance (technical) alarms is the leading cause of alarm fatigue resulting in decreased awareness and a reduction in effective care. The Joint Commission identified in their National Patient Safety goals alarm fatigue as a major safety issue. The introduction of noninvasive respiratory volume monitoring (RVM) has implications for effective perioperative respiratory status management. We evaluated this within the Kaiser Permanente health system.
METHODS: This observational study was conducted at 4 hospitals in the Kaiser Permanente system. Standard data from RVM, pulse oximetry, and capnography were collected postoperatively in the post-anesthesia care unit (PACU) and/or on the general hospital floor. Device-specific alarm types, rates, and respective actions were recorded and analyzed by non-study staff.
RESULTS: RVM was applied to 247 subjects (143 females, body mass index 32.3 ± 8.7 kg/m2, age 60.9 ± 13.9 y) providing 2,321 h. RVM alarms occurred 605 times (0.25 alarms/h); 64% were actionable and addressed, 17% were not addressed, 13% were self-resolved, and only 6% were nuisance. In a subgroup, RVM completed all 127 h of monitoring, whereas oximetry with capnography only completed 51 h with 12.9 alarms/h (73% nuisance). The overall RVM alarm rate was significantly lower than with either pulse oximeters or capnography monitors. We saw a nearly 1,000-fold reduction in nuisance alarms compared to capnography and a 20-50-fold reduction in nuisance alarms compared to pulse oximetry.
CONCLUSIONS: Our study indicates that alarm fatigue due to nuisance alarms continues to be a clinical challenge in perioperative settings. Among the 3 common technologies for respiratory function monitoring, RVM had the lowest rate of overall technical alarms and the highest rate of compliance. Furthermore, with early interventions, none of the subjects monitored with RVM suffered any negative outcomes.

General anesthesia impairs thermoregulation and contributes to perioperative hypothermia; core body temperature monitoring is recommended during surgical procedures lasting > 30 min. Zero-heat-flux core body temperature measurement systems enable continuous non-invasive perioperative monitoring. During a previous trial evaluating the benefits of preoperative forced-air warming, intraoperative temperatures were measured with both a zero-heat-flux sensor and a standard naso-/oropharyngeal temperature probe. The aim of this secondary analysis is to evaluate their agreement. ASA I-III patients, scheduled for elective, non-cardiac surgery under general anesthesia, were enrolled. A zero-heat-flux sensor was placed on the participant\'s forehead preoperatively. Following induction of anesthesia, a \"clinical\" temperature probe was placed in the nasopharynx or oropharynx at the anesthesiologist\'s discretion. Temperature measurements from both sensors were recorded every 10 s. Agreement was analyzed using the Bland-Altman method, corrected for repeated measurements, and Lin\'s concordance correlation coefficient, and compared with existing studies. Data were collected in 194 patients with a median (interquartile range) age of 60 (49-69) years, during surgical procedures lasting 120 (89-185) min. The zero-heat-flux measurements had a mean bias of - 0.05 °C (zero-heat-flux lower) with 95% limits of agreement within - 0.68 to + 0.58 °C. Lin\'s concordance correlation coefficient was 0.823. The zero-heat-flux sensor demonstrated moderate agreement with the naso-/oropharyngeal temperature probe, which was not fully within the generally accepted ± 0.5 °C limit. This is consistent with previous studies. The zero-heat-flux system offers clinical utility for non-invasive and continuous core body temperature monitoring throughout the perioperative period using a single sensor.

During surgery, one of the primary functions of the anesthesiologist is to monitor the patient and ensure safe and effective conduct of anesthesia to provide the optimum operating conditions. Standard guidelines for perioperative monitoring have been firmly established by the American Society of Anesthesiologists. However, in recent years, new advances in technology has led to the development of many new monitoring modalities, especially involving the neurologic and cardiovascular systems. This article presents a targeted review to discuss the functions and limitations of these new monitors and how they are applied in the modern operating room setting.

Since both, hypotension and hypertension, can potentially impair the function of vital organs such as heart, brain, or kidneys, monitoring of arterial blood pressure (BP) is a mainstay of hemodynamic monitoring in acutely or critically ill patients. Arterial BP can either be obtained invasively via an arterial catheter or non-invasively. Non-invasive BP measurement provides either intermittent or continuous readings. Most commonly, an occluding upper arm cuff is used for intermittent non-invasive monitoring. BP values are then obtained either manually (by auscultation of Korotkoff sounds or palpation) or automatically (e.g., by oscillometry). For continuous non-invasive BP monitoring, the volume clamp method or arterial applanation tonometry can be used. Both techniques enable the arterial waveform and BP values to be obtained continuously. This article describes the different techniques for non-invasive BP measurement, their advantages and limitations, and their clinical applicability.

SummaryAortic arch surgery requires complex patient management beyond the manual replacement of the diseased vessel. These procedures include (i) a thorough and pathologically adjusted preoperative evaluation, (ii) initiation and control of cardiopulmonary bypass, (iii) cerebral protection strategies and (iv) techniques to protect the abdominal end organs during prolonged operations. Due to the complexity of aortic arch procedures, multimodal real-time surveillance is required during all stages of the operation. Although having the patient survive the operation is the major goal, further observation is necessary because of the chronicity of the disease. This review summarizes specific aspects of patient management during and after operations requiring periods of circulatory arrest, without necessarily referring to all studies on this topic. The pros and cons of different strategies are weighed against each other, including the personal experience of the authors. A number of questions are raised without providing a \'right\' or \'wrong\' answer. We show that a number of different well-established strategies can result in comparable excellent long-lasting surgical results.

OBJECTIVE: To study the relationship between the values of SvcO2 and SrcO2 in lung resection with one lung ventilation (OLV) and changes in these variables and mean arterial pressure (MAP) and arterial oxygen saturation (SpO2) during the perioperative period.
METHODS: Prospective, observational study of 25 patients in whom pulmonary resection was performed with OLV. The values of MAP, SpO2, SvO2, and SrcO2 were recorded at 6 different times: 1)baseline; 2)double-lung ventilation before the OLV (VBP1); 3)during OLV; 4)after double-lung ventilation (VBP2); 5)30minutes after surgery, and 6)6hours after surgery.
RESULTS: The SrcO2 showed a significant increase from baseline to starting ventilation (65.72±9.05% vs 70.44±7.24%; P<.01). There were no significant changes in their values at the different intraoperative times. Post-operatively, as in the case of the SvcO2, a significant decrease (P<.001) of its value compared with the previous value was observed.
CONCLUSIONS: SrcO2 showed a significant increase after induction of anaesthesia and initiation of mechanical ventilation compared to baseline, and a significant decrease at the end of surgery after extubation in the immediate postoperative period. Being a tissue monitoring, non-invasive technique and with continuous values it can alert the clinician of changes in the ratio of oxygen consumption (VO2) to oxygen delivery (DO2) at times of greatest risk, such as OLV, extubation, and the early postoperative period.