Minimum Mean Arterial Pressure Research Articles

Worse arterial pressure reservoir capacity is associated with exacerbated hemodynamic response to capnogram changes and more labile intraoperative cardiopulmonary-metabolic coupling

Abstract Background The apparent promise of capnography as a cardiac monitor based on the coupled cardiopulmonary response to metabolic changes remains hampered by inconsistent results in studies investigating previous correlations between hemodynamics (e.g.cardiac output) and end-tidal CO2 (EtCO2).(1,2,3) Excess pressure (Pexcess), a dynamic sub-component of pressure waveform representing pressure beyond buffering capacity (reservoir pressure) of elastic large arteries, strongly correlates with aortic flow in humans, suggesting the Pexcess as a promising tool for non-invasive hemodynamic monitoring.(4,5) Purpose We aimed to clarify potential cofounders and pathophysiological mechanisms modifying the EtCO2-arterial hemodynamic coupling, by analysing the intra-operative temporal relations of paired reservoir-excess and capnogram parameters Methods In 190 patients with normal pre-operative pulmonary function tests who underwent non-cardiac surgery, simultaneous capnogram and intra-arterial pressure signals were analysed off-line. Signal windows (>2 minutes) of maximum and minimum mean arterial pressure were autoidentified, the capnogram and pressure signals were averaged into a single representative cycle, to extract reservoir-excess pressure and capnogram parameters (EtCO2, expiratory slope, alpha slope, and plateau slope) accordingly.(6,7) Arterial reservoir capacity (ARC) was defined as Preservoir/Pexcess, which was used to stratify patients into quartiles. Relationships between maximum changes in capnogram and pressure parameters were analysed (Figure 1). Results The ΔEtCO2 and ΔPa mean were correlated significantly in all groups. In patients with the highest ARC (Q4), Pexcess remained unaltered in response to ΔEtCO2 (r:0.095 p:0.545), unlike other subgroups with significant positive correlations. In Q4 (the highest ARC group), the increment in Preservoir was the main cause of ΔPa in relation to ΔEtCO2. In contrast, the ΔEtCO2 - ∆Pexcess relationship was most pronounced in the group with the poorest ARC (r:0.634 p:0.005), underlying the significance of the pressure reservoir behaviour as a determinant of metabolic oscillations in arterial hemodynamics, even though the changes in ΔEtCO2 were equivalent.(Figure 2) Conclusion(s) Worse arterial pressure reserve capacity is associated with an exacerbated hemodynamic response to capnogram changes and a more labile cardiopulmonary-metabolic coupling, characterised by a pronounced increase in excess pressure in response to increased EtCO2 in patients with low ARC. Substantial Pa alterations accompanying EtCO2 changes had opposite drivers in low and high ARC groups (predominant augmentation of Preservoir vs Pexcess). Utilisation of the capnogram for cardiac hemodynamic monitoring is substantially affected by ARC, hence it should be considered while developing capnogram-based monitoring indices.Figure 1.Methodology and example casesFigure 2.Main results

Evaluation of the Predictive Character of the Expiratory Inferior Vena Cava/Abdominal Aorta (eIVC/Ao) Index for Minimum Blood Pressure Following Spinal Anesthesia With 0.5% Hyperbaric Bupivacaine.

Spinal anesthesia has many side effects, one of them being a drop in blood pressure (BP). Identifying predictive factors for this drop is a clear matter of concern. In this regard, the expiratory inferior vena cava/abdominal aorta (eIVC/Ao) index has already been spotted as such for doses of 0.5% hyperbaric bupivacaine greater than 12mg. Departing from the demonstrated correlation between this index and hypotension post-spinal anesthesia, our study aimed to (1) evaluate whether an eIVC/Ao index greater than 0.7, thus defining non-hypovolemic patients, can also predict minimal BP for doses inferior to 12mgand (2) identify other predictive factors for minimal BP post-spinal anesthesia. Lastly, we verified whether preoperative fasting induces hypovolemia. This single-center prospective observational pilot study included 20 patients. The baseline measurements of BP, eIVC/Ao index, and fasting time were recorded at time T0'. Then spinal anesthesia was administered with 0.5% hyperbaric bupivacaine in doses inferior to 12 mg. The patients' systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and metameric levels were each recorded at times T5', T10', T15', and T20'. The results indicated that baseline DBP was predictive of low DBP and minimum MAP, which reflect myocardial perfusion and systemic pressures, respectively. Therefore, it should trigger prophylaxis (spinal-lateralized, continuous, or lower dose) in patients with a low DBP baseline. Additionally, baseline SBP was predictive of minimumSBP, an independent risk factor for post-anesthetic hypotension if its baseline is lessthan 120 mmHg. Although female gender was linked to minimum SBP, other confounding factors (size, dose administered, and type of surgery related to gender) must also be considered. Moreover, a correlation was established between height and MAP in parturients. Hypotension was not recorded at local anesthetic (LA) doses between 8 and 12 mg and the doses administered were sufficient to achieve the metameric levels required for surgery (ether tests). Since 8 mg of 0.5% hyperbaric bupivacaine achieved the same level as 12 mg, lower doses of LA might prevent a significant drop in BP and its deleterious effects. Therefore, in the current cohort, the eIVC/Ao index was not predictive of minimum BP during spinal anesthesia with doses less than 12 mg of 0.5% hyperbaric bupivacaine. However, predictive factors for minimum BP included gender and baseline SBP (for minimum SBP), height and baseline DBP (for minimum MAP), and baseline DBP (for minimum DBP). Lastly, preoperative fasting did not cause hypovolemia.

A nomogram to predict the risk of surgery-related pressure ulcers in patients undergoing cardiovascular surgery.

In this study, we aimed to establish a new nomogram score to predict the occurrence of surgery-related pressure ulcers (SRPU) in patients undergoing cardiovascular surgery. We conducted a retrospective study among patients who underwent cardiovascular surgery between February 2016 and November 2020. We established a prediction model based on a logistic regression model and tested the calibration and discrimination. We included 1163 patients who had undergone cardiovascular surgery. We formulated the logistic regression model, with Logit(P) = -11.745 + 0.024 preoperative hemoglobin value + 0.118 serum sodium value - 0.014 prealbumin value - 0.213 intraoperative mean temperature - 0.058 minimum mean arterial pressure + 0.646 preoperative blood potassium value + 0.264 smoking frequency + 0.760 hypertension history + 0.536 age ≥70 years. In this model ,"+" indicates that the factor is positively related to the occurrence risk of SRPU and "-" indicates that the factor is negatively associated with SRPU risk. The predictive model and nomogram had good accuracy in estimating the risk of SRPU, with a C-index of 0.755 (95% confidence interval: 0.719-0.792). The present model can be used to effectively screen patients with a high risk of SRPU to devise targeted nursing intervention strategies and ultimately reduce the incidence rate of SRPU.

Efficacy and safety of remimazolam compared with propofol in hypertensive patients undergoing breast cancer surgery: a single-center, randomized, controlled study

BackgroundRemimazolam, as a novel anesthetic, has recently been shown to improve hemodynamic stability during anesthesia induction and maintenance; however, it has not been reported in the hypertensive population. This study aimed to compare the effects of remimazolam and propofol on hemodynamic stability in hypertensive patients undergoing breast cancer surgery.MethodsWe enrolled 120 hypertensive patients undergoing breast cancer surgery in this prospective study and randomly allocated them to remimazolam (n = 60) or propofol (n = 60) groups. Anesthesia regimens were consistent between groups, except for the administration of remimazolam and propofol. Our primary outcome was the incidence of post-induction hypotension, which was either an absolute mean arterial pressure (MAP) < 60 mmHg or a > 30% relative drop in MAP compared to baseline within 20 min of induction or from induction to the start of surgery. Secondary outcomes included minimum MAP and MAP at different time points during anesthesia, the application of vasoactive drugs, adverse events, and the patient’s self-reported Quality of Recovery-40 scale for the day after surgery.ResultsThe incidence of post-induction hypotension was lower and the minimum MAP during induction was higher in the remimazolam group than those in the propofol group. There were no significant differences between the two groups in the remaining outcomes.ConclusionRemimazolam is safe and effective in hypertensive patients undergoing breast cancer surgery. Induction with remimazolam in hypertensive patients may result in more stable hemodynamics than propofol.Trial registrationThis study was registered at the Chinese Clinical Trials Registry (http://www.chictr.org.cn) on 03/12/2020, with registration number ChiCTR2000040579.

Tight perioperative blood pressure management to reduce complications: a randomised feasibility trial

ObjectiveEvaluate the feasibility of a trial of perioperative hypotension and serious complications.DesignA patient and assessor-blinded randomised feasibility trial.SettingWe included patients in a tertiary university hospital.ParticipantsWe enrolled 80 adults scheduled for...

Influence of perioperative blood pressure regulation on postoperative delirium in patients undergoing head and neck free flap reconstruction

BackgroundPostoperative delirium (POD) is a serious complication in patients undergoing microvascular head and neck reconstruction. Whether intraoperative and postoperative blood pressure regulation are risk factors for POD remains unclear. This study aimed to highlight the relationships between intraoperative and postoperative blood pressure regulation and POD in microvascular head and neck reconstruction.MethodsData from 433 patients who underwent microvascular head and neck reconstruction at our department of oral and maxillofacial surgery between 2011 and 2019 were retrospectively analyzed. The 55 patients with POD were matched with 55 patients without POD in terms of tracheotomy, flap type, and flap location, and the intraoperative and postoperative systolic and mean blood pressure values were compared between the two groups.ResultsPatients with POD showed lower intraoperative and postoperative minimum mean arterial pressure (MAP) values than patients without POD (60.0 mmHg vs. 65.0 mmHg, p < 0.001; and 56.0 mmHg vs. 62.0 mmHg, p < 0.001; respectively). A lower intraoperative minimum MAP value was identified as predictor for POD (odds ratio [OR] 1.246, 95% confidence interval [CI] 1.057–1.472, p = 0.009). The cut-off value for intraoperative MAP for predicting POD was ≤ 62.5 mmHg (area under the curve [AUC] 0.822, 95% CI 0.744–0.900, p < 0.001).ConclusionsMaintaining a stable intraoperative minimum MAP of > 62.5 mmHg could help to reduce the incidence of POD in microvascular head and neck reconstruction.

Association of Blood Pressure Variability With Death and Discharge Destination Among Critically Ill Patients With and Without Stroke.

It is unclear whether blood pressure variability's (BPV) association with worse outcomes is unique to patients with stroke or a risk factor among all critically ill patients. We (1) determined whether BPV differed between patients with stroke and nonstroke patients, (2) examined BPV's associations with in-hospital death and favorable discharge destination in patients with stroke and nonstroke patients, and (3) assessed how minimum mean arterial pressure (MAP)-a correlate of illness severity and cerebral perfusion-affects these associations. This is a retrospective analysis of adult intensive care unit patients hospitalized between 2001 and 2012 from the Medical Information Mart for Intensive Care III database. Confounder-adjusted logistic regressions determined associations between BPV, measured as SD and average real variability (ARV), and (1) in-hospital death and (2) favorable discharge, with testing of minimum MAP for effect modification. BPV was higher in patients with stroke (N = 2,248) compared with nonstroke patients (N = 9,085) (SD mean difference 2.3, 95% CI 2.1-2.6, p < 0.01). After adjusting for minimum tertile of MAP and other confounders, higher SD remained significantly associated (p < 0.05) with higher odds of in-hospital death for patients with acute ischemic strokes (AISs, odds ratio [OR] 2.7, 95% CI 1.5-4.8), intracerebral hemorrhage (ICH, OR 2.6, 95% CI 1.6-4.3), subarachnoid hemorrhage (SAH, OR 3.4, 95% CI 1.2-9.3), and pneumonia (OR 1.9, 95% CI 1.1-3.3) and lower odds of favorable discharge destination in patients with ischemic stroke (OR 0.3, 95% CI 0.2-0.6) and ICH (OR 0.4, 95% CI 0.3-0.6). No interaction was found between minimum MAP tertile with SD (p > 0.05). Higher ARV was not significantly associated with increased risk of death in any condition when adjusting for illness severity but portended worse discharge destination in those with AIS (OR favorable discharge 0.4, 95% CI 0.3-0.7), ICH (OR favorable discharge 0.5, 95% CI 0.3-0.7), sepsis (OR favorable discharge 0.8, 95% CI 0.6-1.0), and pneumonia (OR favorable discharge 0.5, 95% CI 0.4-0.8). BPV is higher and generally associated with worse outcomes among patients with stroke compared with nonstroke patients. BPV in patients with AIS and patients with ICH may be a marker of central autonomic network injury, although clinician-driven blood pressure goals likely contribute to the association between BPV and outcomes.

Analysis of factors associated with postoperative acute kidney injury in patients with colorectal cancer and the development of a risk prediction model: a retrospective study.

To investigate the factors associated with acute kidney injury (AKI) in postoperative colorectal cancer (CRC) patients and develop a risk prediction model. The clinical data of 389 CRC patients were retrospectively analyzed. The patients were divided into AKI (n = 30) and non-AKI groups (n = 359) according to KDIGO diagnostic criteria. Demographic data, the presence of underlying diseases, perioperative conditions and related examination results were compared between the two groups. Binary logistic regression was used to analyze the independent risk factors for postoperative AKI, and a risk prediction model was established. And a verification group (94 patients) was used to verify the model. 30 patients (7.71%) with CRC had postoperative AKI. Binary logistic regression analysis showed that preoperative combined hypertension, preoperative anemia, inadequate intraoperative crystalloid infusion, low intraoperative minimum mean arterial pressure (MAP) and moderate to severe postoperative decline in hemoglobin (Hb) levels were independent risk factors. The risk prediction model developed was expressed as Logit P = -0.853 + 1.228 * preoperative combined hypertension + 1.275 *preoperative anemia -0.002 * intraoperative crystalloid infusion (ml) -0.091 * intraoperative minimum MAP (mmHg) + 1.482 * moderate to severe postoperative decline in Hb levels. In Hosmer-Lemeshow test, χ2 = 8.157, P = 0.718 showed that the fitting effect was good. The area under ROC curve was 0.776 (95% CI 0.682-0.871, P < 0.001), with a prediction threshold of 1.570, a sensitivity of 63.3% and a specificity of 88.9%. The sensitivity and specificity of the verification group were 65.8% and 86.1%. Preoperative combined hypertension, preoperative anemia, inadequate intraoperative crystalloid infusion, low intraoperative minimum MAP, and moderate to severe postoperative decline in Hb levels were independent risk factors for AKI development in CRC patients. The prediction model can effectively predict the occurrence of postoperative AKI in patients with CRC.

Risk Factors and Prediction of Postoperative Delirium in Aortic Arch Replacement: A Retrospective Cohort Study

ABSTRACT Objective: This study aimed to explore the risk factors and prediction of postoperative delirium (POD) in aortic arch replacement. Methods: The preoperative, intraoperative, and postoperative clinical data of patients undergoing aortic arch replacement in our hospital from January 1, 2018, to March 31, 2019, were retrospectively analyzed. According to whether POD occurred, cases were divided into delirium group and control group. The clinical data of the patients were firstly screened by univariate analysis, and then the meaningful variables were analyzed by multivariate logistic regression analysis. The receiver operating characteristic curve was used to analyze the meaningful factors in predicting the occurrence of POD after aortic arch replacement. Results: A total of 162 patients were included in the study. The prevalence of POD was 46.9% (n = 76). The results of univariate and multivariate analyses showed that the intraoperative minimum mean arterial pressure (MAP) (odds ratio [OR] = 0.635, 95% confidence interval [CI] = 0.5510.731, P &lt; 0.001), postoperative C-reactive protein (OR = 1.010, 95% CI = 1.0031.018, P = 0.005), and postoperative infection (OR = 3.148, 95% CI = 1.1188.867, P = 0.030) were the independent risk factors for POD in aortic arch replacement. Among them, the intraoperative minimum MAP has the best prediction effect. When its cutoff value reaches ≤ 49 mmHg, the specificity for predicting POD is 84.88% and the sensitivity is 81.58%. Conclusions: A lower intraoperative minimum MAP is an independent risk factor and has the predictive value for POD in aortic arch replacement.

Would surgical Apgar score be useful to predict postoperative complications after proximal femoral fracture surgery? - A retrospective cohort study.

The surgical Apgar score (SAS) is a perioperative risk evaluation score, which considers intraoperative minimum heart rate, minimum mean arterial pressure and estimated blood loss. Although validated in multiple surgical fields, SAS remains quite controversial in the orthopedic one. The main purpose of this study was to investigate if SAS relates with the occurrence of complications during the first 30-days after proximal femoral fracture surgery. Retrospective study including all consecutive patients submitted to proximal femoral fracture surgery between January and July 2019. Patients with no information about SAS were excluded. Patients were divided in two groups, based on the occurrence of complications during the first 30 post-operative days and their SAS calculated. Receiver operating characteristic (ROC) curves were used to assess SAS power as a predictive model of complications. Forty-two percent (n=76) of the 181 patients included in the study developed complications during the first 30 postoperative days. Eight patients (4,4%) died during that period. The patient's mean age was 79 years and 30,9% (n=56) were men. Heart failure, pacemaker use, chronic kidney disease, chronic obstructive pulmonary disease and dementia were significantly associated with post-operative morbidity. There was no significant correlation between SAS and the occurrence of complications during the first 30 postoperative days. The AUC of SAS as a predictive model for postoperative complications after proximal femoral fracture surgery was 0,522, being insufficient to be considered an accepted model of prediction. Based on this study, we conclude that SAS is not predictive of the development of complications in the first 30 post-operative days in patients submitted to proximal femoral fracture surgery. However, other clinical factors have been identified as associated with postoperative morbidity. In the future, prospective-based studies with higher samples may better clarify the role of SAS in this context.

Safety and efficacy of target controlled infusion administration of propofol and remifentanil for moderate sedation in non-hospital dental practice.

Fearful and anxious patients who find dental treatment intolerable without sedative and analgesic support may benefit from moderate sedation. Target controlled infusion (TCI) pumps are superior to bolus injection in maintaining low plasma and effect-site concentration variability, resulting in stable, steady-state drug concentrations. We evaluated the safety and efficacy of moderate sedation with remifentanil and propofol using TCI pumps in non-hospital dental settings. A prospective chart review was conducted on 101 patients sedated with propofol and remifentanil using TCI pumps. The charts were completed at two oral surgeons and one general dentist's office over 6 months. Hypoxia, hypotension, bradycardia, and over-sedation were considered adverse events and were collected using Tracking and Reporting Outcomes of Procedural Sedation (TROOPS). Furthermore, patient recovery time, sedation length, drug dose, and patient satisfaction questionnaires were used to measure sedation effectiveness. Of the 101 reviewed sedation charts, 54 were of men, and 47 were of women. The mean age of the patients was 40.5 ±18.7 years, and their mean BMI was 25.6 ± 4.4. The patients did not experience hypoxia, bradycardia, and hypotension during the 4694 min of sedation. The average minimum Mean Arterial Pressure (MAP) and heartbeats were 75.1 mmHg and 60.4 bpm, respectively. 98% of patients agreed that the sedation technique met their needs in reducing their anxiety, and 99% agreed that they were satisfied with the sedation 24 hours later. The average sedation time was 46.9 ± 55.6 min, and the average recovery time was 12.4 ± 4.4 min. Remifentanil and propofol had mean initial effect-site concentration doses of 0.96 µ/ml and 1.0 ng/ml respectively. The overall total amount of drug administered was significantly higher in longer sedation procedures compared to shorter ones, while the infusion rate decreased as the procedural stimulus decreased. According to the results of this study, no patients experienced adverse events during sedation, and all patients were kept at a moderate sedation level for a wide range of sedation times and differing procedures. The results showed that TCI pumps are safe and effective for administering propofol and remifentanil for moderate sedation in dentistry.

Intraoperative hypotension during surgical treatment for Marfan syndrome scoliosis in children.

Purpose:To explore the occurrence and risk factors of intraoperative hypotension during children’s Marfan syndrome scoliosis surgery and summarize the associated hemodynamic features and handle measures.Methods:Twenty-two Marfan syndrome scoliosis patients who underwent spinal surgery at Beijing Children’s Hospital were retrospectively reviewed between January 2001 and January 2020. Intraoperative hypotension is defined as the minimum mean arterial pressure ≤ 60 mm Hg. The patients were divided into the hypotension group and the control group. Clinical, radiographic, and operative data were compared between the two groups. The risk factors, hemodynamic features, and handle measures for intraoperative hypotension in Marfan syndrome scoliosis surgery were analyzed and summarized.Results:Twenty-two patients were included in the study, with a mean age of 11.4 years at initial surgery. The follow-up period ranged from 24 to 152 months. Intraoperative hypotension occurred in 14 cases, with an incidence of 63.6%. The proportion of pulmonary dysfunction in the hypotension group was higher than in the control group (100.0% vs 50.0%, p < 0.05). The spinal flexibility was significantly lower in the hypotension group (28.3% ± 14.2% vs 46.5% ± 11.5%, p < 0.05). Fourteen patients with intraoperative hypotension had decreased intraoperative systolic blood pressure 21.0%–50.0% compared with baseline. One patient had a transient decrease in the muscle strength of the lower limbs. No complications were observed during the follow-up.Conclusion:The incidence of intraoperative hypotension in Marfan syndrome scoliosis children who underwent surgery was 63.6%. The risk factors included preoperative pulmonary dysfunction and poor spinal flexibility. Comprehensive preoperative evaluation and effective hemodynamic handling measures should be undertaken to prevent further complications in children with Marfan syndrome scoliosis.

COVID-19 Time of Intubation Mortality Evaluation (C-TIME): A system for predicting mortality of patients with COVID-19 pneumonia at the time they require mechanical ventilation.

An accurate system to predict mortality in patients requiring intubation for COVID-19 could help to inform consent, frame family expectations and assist end-of-life decisions. To develop and validate a mortality prediction system called C-TIME (COVID-19 Time of Intubation Mortality Evaluation) using variables available before intubation, determine its discriminant accuracy, and compare it to acute physiology and chronic health evaluation (APACHE IVa) and sequential organ failure assessment (SOFA). A retrospective cohort was set in 18 medical-surgical ICUs, enrolling consecutive adults, positive by SARS-CoV 2 RNA by reverse transcriptase polymerase chain reaction or positive rapid antigen test, and undergoing endotracheal intubation. All were followed until hospital discharge or death. The combined outcome was hospital mortality or terminal extubation with hospice discharge. Twenty-five clinical and laboratory variables available 48 hours prior to intubation were entered into multiple logistic regression (MLR) and the resulting model was used to predict mortality of validation cohort patients. Area under the receiver operating curve (AUROC) was calculated for C-TIME, APACHE IVa and SOFA. The median age of the 2,440 study patients was 66 years; 61.6 percent were men, and 50.5 percent were Hispanic, Native American or African American. Age, gender, COPD, minimum mean arterial pressure, Glasgow Coma scale score, and PaO2/FiO2 ratio, maximum creatinine and bilirubin, receiving factor Xa inhibitors, days receiving non-invasive respiratory support and days receiving corticosteroids prior to intubation were significantly associated with the outcome variable. The validation cohort comprised 1,179 patients. C-TIME had the highest AUROC of 0.75 (95%CI 0.72-0.79), vs 0.67 (0.64-0.71) and 0.59 (0.55-0.62) for APACHE and SOFA, respectively (Chi2 P<0.0001). C-TIME is the only mortality prediction score specifically developed and validated for COVID-19 patients who require mechanical ventilation. It has acceptable discriminant accuracy and goodness-of-fit to assist decision-making just prior to intubation. The C-TIME mortality prediction calculator can be freely accessed on-line at https://phoenixmed.arizona.edu/ctime.

Dysautonomia following breast surgery: Disproportionate response to postoperative hematoma

BackgroundUp to 10% of patients undergoing breast surgery suffer from bleeding complications. Some experience severe hypotension and bradycardia of unclear etiology. Similar to the vasovagal hyperstimulation provoked by abdominal insufflation during laparoscopic surgery, we hypothesize that chest wall stretch from postoperative breast hematoma may mechanically stretch the vagus nerve, triggering dysautonomia disproportionate to the degree of blood loss. MethodsA single-institution retrospective review of patients requiring reoperation for hematoma evacuation following breast surgery between 2011 and 2021 was performed. The relationship between hematoma volume and hemodynamic instability, as well as hematoma volume and vasovagal symptoms, was measured. ResultsSixteen patients were identified. Average hematoma volume was 353 mL, and average minimum mean arterial pressure was 64 mm Hg (range: 34–102 mm Hg). Fifty-six percent of patients reported symptoms including dizziness, somnolence, and/or syncope. Accounting for body surface area, patients with larger hematomas had similar minimum mean arterial pressures compared to those with smaller hematomas, 55 and 73 mm Hg, respectively (P = .0943). However, patients in the large hematoma group experienced over 3 times as many vasovagal symptoms, 88% and 25%, respectively (P = .0095). ConclusionPatients with large hematomas reported significantly more vagal symptoms compared to those with small hematomas despite similar mean arterial pressures. In addition, the trend of lower mean arterial pressures and heart rates more closely resembles vagal hyperstimulation than hypovolemic shock. Early hematoma evacuation to relieve vagal nerve stretch and parasympatholytics to reverse dysautonomia are targeted interventions to consider in this patient population rather than fluids, vasopressors, and blood products that are used in cases of hemodynamic instability due to hypovolemia alone.

A Novel Hemodynamic Index of Post-operative Right Heart Dysfunction Predicts Mortality in Cardiac Surgical Patients.

This study aimed to investigate whether mortality following cardiac surgery was associated with the pulmonary artery pulsatility index (PAPi): pulmonary artery pulse pressure divided by central venous pressure (CVP), and a novel index: mean pulmonary artery pressure (mPAP) minus CVP. This retrospective analysis investigated all cardiac surgery patients in the Society of Thoracic Surgeons registry at a single academic medical center from January 2017 through March 2020 (n = 1510). The primary and secondary outcomes were mortality at 1 year and serum creatinine increase during index surgical admission, respectively. CVP, mPAP, PAPi, mPAP-CVP gradient, mean arterial pressure (MAP), and cardiac index (CI) were sampled continually from invasive hemodynamic monitors post-operatively. Associations with mortality were tested with univariate and multivariate analyses. The relationship with serum creatinine was investigated with Pearson's correlation at alpha = .05. One-year mortality was observed in 44/1200 patients (3.7%). On univariate analysis, mortality was associated with minimums for mPAP, MAP, and CI and maximums for CVP, mPAP, PAPi, mPAP-CVP gradient, and CI (all P < .10). Model selection revealed that the only independently predictive parameters were minimum MAP (AOR = .880 [.819-.944]), maximum mPAP-CVP gradient (AOR = 1.082 [1.031-1.133]), and maximum CI (AOR = 1.421 [.928-2.068]), with model c-statistic = .770. A maximum mPAP-CVP gradient >20.5 predicted mortality with 54.5% sensitivity and 79.30% specificity, maintaining significance on survival analysis (P < .001). Peak increase in serum creatinine from baseline demonstrated a weak association with all parameters (max |r| = .33). Mortality was not predicted by the post-operative PAPi; rather, it was independently predicted by the mPAP-CVP gradient, MAP, and CI.

Comparison of the Hemodynamic Changes in Normotensive and Severe Preeclamptic Pregnant Woman Posted For Cesarean Section under Spinal Anaesthesia

Background: Spinal anesthesia is widely considered a technique of choice for cesarean delivery. But due to fear of sudden and extensive sympathetic blockade, spinal anesthesia may not be considered safe in severe preeclampsia. Objectives: The aim of the present study was to compare the heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), incidence of hypotension, phenyl ephrine requirement and neonatal outcome between normotensive and severe pre-eclamptic women undergoing cesarean section under spinal anesthesia. Material and Methods: A total of 35 severe pre-eclamptic (BP &gt; 160/110 mmHg) 3(Group A) and 35 healthy parturients (group B), meeting the inclusion criteria were included in the study. After preloading with 10 ml/kg of ringer lactate (RL) solution spinal anesthesia was administered with 12.5 mg of hyper baric bupivacaine. Heart rate and blood pressure were recorded before spinal anesthesia and thereafter at 3 minute intervals upto 60 minutes. Hypotension was defined as MAP LESS,THAN 30% of the baseline or a decrease in SBP to LESS THAN 100 mm Hg over the same time interval and was treated with 50 mcg phenylephrine intravenously (i.v). Apgar score was noted 1 and 5 min after birth. Results: The incidence rate of hypotension among the preeclamptic patients was lower than that of the healthy parturients (55.6% vs. 34.1%). The minimum SBP, DBP, and MAP recorded were lower in normotensive, and the difference between two groups was statistically significant. The mean phenylephrine requirement in the normotensive group (151.1 ± 70) was significantly greater (P LESS THAN 0.0001) than that of pre-eclamptic group (48.3 ± 35). The total doses of IV Phenylephrine for treating hypotension were significantly lower among the preeclamptic patients (72 mcg in preeclamptic patients versus 188 mcg in normotensive patients) (P LESS THAN 0.05). There was no statistical difference in the neonatal outcome and Apgar score in the study groups. Conclusion: Pre-eclamptics experienced less hypotension following subarachnoid block (SAB) than normotensives and required less phenylephrine with comparable fetal Apgar scores.

Comparison of the Hemodynamic Changes in Normotensive and Severe Preeclamptic Pregnant Woman Posted For Cesarean Section under Spinal Anaesthesia

Background: Spinal anesthesia is widely considered a technique of choice for cesarean delivery. But due to fear of sudden and extensive sympathetic blockade, spinal anesthesia may not be considered safe in severe preeclampsia. Objectives: The aim of the present study was to compare the heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), incidence of hypotension, phenyl ephrine requirement and neonatal outcome between normotensive and severe pre-eclamptic women undergoing cesarean section under spinal anesthesia. Material and Methods: A total of 35 severe pre-eclamptic (BP &gt; 160/110 mmHg) 3(Group A) and 35 healthy parturients (group B), meeting the inclusion criteria were included in the study. After preloading with 10 ml/kg of ringer lactate (RL) solution spinal anesthesia was administered with 12.5 mg of hyper baric bupivacaine. Heart rate and blood pressure were recorded before spinal anesthesia and thereafter at 3 minute intervals upto 60 minutes. Hypotension was defined as MAP LESS,THAN 30% of the baseline or a decrease in SBP to LESS THAN 100 mm Hg over the same time interval and was treated with 50 mcg phenylephrine intravenously (i.v). Apgar score was noted 1 and 5 min after birth. Results: The incidence rate of hypotension among the preeclamptic patients was lower than that of the healthy parturients (55.6% vs. 34.1%). The minimum SBP, DBP, and MAP recorded were lower in normotensive, and the difference between two groups was statistically significant. The mean phenylephrine requirement in the normotensive group (151.1 ± 70) was significantly greater (P LESS THAN 0.0001) than that of pre-eclamptic group (48.3 ± 35). The total doses of IV Phenylephrine for treating hypotension were significantly lower among the preeclamptic patients (72 mcg in preeclamptic patients versus 188 mcg in normotensive patients) (P LESS THAN 0.05). There was no statistical difference in the neonatal outcome and Apgar score in the study groups. Conclusion: Pre-eclamptics experienced less hypotension following subarachnoid block (SAB) than normotensives and required less phenylephrine with comparable fetal Apgar scores.

Increased risk of hip fracture mortality associated with intraoperative hypotension in elderly hip fracture patients is related to under resuscitation

BackgroundAs the US and world population ages, hip fractures are increasingly more common. The mortality associated with these fractures remains high both in the immediate postoperative period and at one year. Perioperative resuscitation in this population is of key interest to prevent organ injury and mortality. Our objectives were to evaluate the effect of fluid resuscitation and hemodynamic status in the form of mean arterial pressure (MAP) on inpatient mortality of hip fracture patients. MethodsAn institutional database was queried to compare elderly hip fracture patients that sustained in-hospital mortality to a matched control cohort. Pre-, intra-, and post-operative intravenous fluid (IVF) administration and MAP were extracted from the electronic medical record. Time from hospital presentation to the OR was also recorded. Results1,114 total hip fractures were identified during the two-year study period, 16 of which suffered inpatient mortalities. The mortality cohort was then matched with a control of 394 hip fracture patients for the same period based on age, sex, and Charlson Comorbidity Index (CCI). Conditional logistical regression analysis found odds ratios (OR) indicating that longer time between presentation and surgery (OR per additional hour: 1.05; 95% CI: 1.01–1.08) and lower intraoperative minimum MAP (OR per 5 mmHg decrease: 0.77; 95% CI: 0.61–0.97) were associated with significantly increased odds of mortality. There was also a marginal relationship between greater intraoperative IVF administration and reduced odds of mortality (OR per 500 cc additional fluid: 0.61; 95% CI: 0.37–1.00). ConclusionExtended time from presentation to surgery and intraoperative hypotension were associated with increased likelihood of inpatient mortality in an elderly hip fracture cohort, with a possible additional effect of under-resuscitation. Further investigation into a safe intraoperative minimum MAP should be pursued. Level of evidenceLevel III.

Impact of Enteral Albuterol on Bradycardic Events After Acute Cervical Spinal Cord Injury.

Acute cervical spinal cord injury (ACSCI) is commonly complicated by spinal shock, resulting in hemodynamic instability characterized by bradycardia and hypotension that can have fatal consequences. Current guidelines recommend the use of intravenous beta and dopamine agonists, such as norepinephrine and dopamine, respectively. We sought to determine whether enteral albuterol would be a safe and feasible treatment for bradycardia without an increase in the occurrence of known side effects of albuterol in patients with ACSCI. A retrospective review of patients with ACSCI admitted to an intensive care unit at a level I trauma center and treated with enteral albuterol was conducted. Patients were excluded for the following reasons: pure beta blocker use prior to injury, concurrent use of pacemaker, age of less than 18years, or agemore than 75years. As part of the standard of care, all patients underwent mean arterial pressure (MAP) augmentation to reach a goal of greater than 85mm Hg during the first 7days post injury. All eligible patient charts were reviewed for demographic characteristics, daily minimum and maximum heart rate and MAP, and concomitant vasoactive medication use. Bradycardia and tachycardia were defined as heart rate less than 60 beats per minute (bpm) and greater than 100bpm, respectively. Factors found to be associated with bradycardia on univariate analysis were entered into a multivariable generalized estimating equation analysis to determine factors independently associated with bradycardia during the study period. There were 58 patients with cervical ASCI (age 45 ± 18years, 76% men) admitted between January 1, 2016, and December 31, 2017, that met the study criteria. The mean time to initiation of albuterol was 1.5 ± 1.7days post injury, with a duration of 9.3 ± 4.5days and a mean daily dosage of 7.8 ± 4.5mg. Bradycardia was observed in 136 of 766 patient days (17%). There were a few episodes of hyperglycemia (1%) and tachycardia (3%), but no episodes of hypokalemia. In a multivariable analysis, female sex (P = 0.006) and American Spinal Cord Injury Association grade A, B, or C (P < 0.001) were associated with a higher risk of developing bradycardia, whereas dosage of albuterol (P = 0.009) and norepinephrine use (P = 0.008) were associated with a lower risk of developing bradycardia. Albuterol administration in ASCI is a safe and feasible treatment for bradycardia, given that no significant side effects, such as hyperglycemia, hypokalemia, or tachycardia, were observed. The administration of enteral albuterol was well tolerated and, in a dose-dependent manner, associated with a lower occurrence of bradycardia. Further prospective trials for the use of enteral albuterol after SCI are warranted.

Associations between intraoperative and post-anesthesia care unit hypotension and surgical ward hypotension

Study objectiveTo test whether patients who experience hypotension in the post-anesthesia care unit or during surgery are most likely to experience hypotension on surgical wards. DesignA prediction study using data from two randomized controlled trials. SettingOperating room, post-anesthesia care unit, and surgical ward. Patients550 adult patients having abdominal surgery with ASA physical status I-IV. InterventionsBlood pressure measurement per routine intraoperatively, and with continuous non-invasive monitoring postoperatively. MeasurementsThe primary predictors were minimum mean arterial pressure (<60, <65, <70 and < 80 mmHg) and minimum systolic blood pressure (<70, <75, <80, <85 mmHg) in the post-anesthesia care unit. The secondary predictors were intraoperative minimum blood pressures with the same thresholds as the primary ones. Our outcome was ward hypotension defined as mean pressure < 70 mmHg or systolic pressure < 85 mmHg. A threshold was considered clinically useful if both sensitivity and specificity exceeded 0.75. Main resultsMinimum mean and systolic pressures in the post-anesthesia care unit similarly predicted ward mean or systolic hypotension, with the areas under the curves near 0.74. The best performing threshold was mean pressure < 80 mmHg in the post-anesthesia care unit which had a sensitivity of 0.41 (95% confidence interval [CI], 0.35, 0.47) and specificity of 0.91 (95% CI, 0.87, 0.94) for ward mean pressure < 70 mmHg and a sensitivity of 0.44 (95% CI, 0.37, 0.51) and specificity of 0.88 (95% CI, 0.84, 0.91) for ward systolic pressure < 85 mmHg. The areas under the curves using intraoperative hypotension to predict ward hypotension were roughly similar at about 0.60, with correspondingly low sensitivity and specificity. ConclusionsIntraoperative hypotension poorly predicted ward hypotension. Pressures in the post-anesthesia care unit were more predictive, but the combination of sensitivity and specificity remained poor. Unless far better predictors are identified, all surgical inpatients should be considered at risk for postoperative hypotension.