Occurrence Of Intraoperative Hypotension Research Articles

Intraoperative Hypotension Prediction-A Proactive Perioperative Hemodynamic Management-A Literature Review.

Intraoperative hypotension (IH) is a frequent phenomenon affecting a substantial number of patients undergoing general anesthesia. The occurrence of IH is related to significant perioperative complications, including kidney failure, myocardial injury, and even increased mortality. Despite advanced hemodynamic monitoring and protocols utilizing goal directed therapy, our management is still reactive; we intervene when the episode of hypotension has already occurred. This literature review evaluated the Hypotension Prediction Index (HPI), which is designed to predict and reduce the incidence of IH. The HPI algorithm is based on a machine learning algorithm that analyzes the arterial pressure waveform as an input and the occurrence of hypotension with MAP <65 mmHg for at least 1 min as an output. There are several studies, both retrospective and prospective, showing a significant reduction in IH episodes with the use of the HPI algorithm. However, the level of evidence on the use of HPI remains very low, and further studies are needed to show the benefits of this algorithm on perioperative outcomes.

Prediction of risk factors for intraoperative hypotension during general anesthesia undergoing carotid endarterectomy.

ObjectiveCarotid endarterectomy (CEA) has been considered as “gold standard” treatment for patients with significant carotid stenosis Intra-operative hypotension was a risk factor for post-operative complications in patients undergoing CEA. This study aimed to investigate the predictors for intra-operative hypotension during CEA.MethodsThis retrospective study included consecutive patients underwent CEA from June 1, 2020 to May 31, 2021 in the neurosurgery department of Xuanwu Hospital, Capital Medical University. The intraoperative hypotension was defined as blood pressure (BP) of 20% below standard value for longer than 5 min. Univariable and multivariable analyses were performed to identify the prediction of risk factors for intraoperative hypotension.ResultsOverall, 367 patients were included, and 143 (39.0%) patients had hypotension during CEA procedure. Univariate analysis indicated Grade 3 hypertension (P = 0.002), peripheral artery disease (P = 0.006) and shunting (P = 0.049) were associated with occurrence of intraoperative hypotension during CEA procedure. On multivariable analysis, Grade 3 hypertension (P = 0.005), peripheral artery disease (P = 0.009), and shunting (P = 0.034) were all found to be independent predicting factors of hypotension during the CEA process.ConclusionIntraoperative hypotension is a dynamic phenomenon may be affected by patients with grade 3 hypertension, peripheral artery disease and intra-operative shunting. It is necessary to pay special attention to these patients, both intraoperatively and postoperatively, to improve the final clinical outcome.

Effect of remifentanil on post-operative analgesic consumption in patients undergoing shoulder arthroplasty after interscalene brachial plexus block: a randomized controlled trial

Remifentanil is useful in balanced anesthesia; however, there is concern regarding opioid-induced hyperalgesia. The effect of remifentanil on rebound pain, characterized by hyperalgesia after peripheral nerve block has rarely been studied. This study evaluated whether intraoperative remifentanil infusion may increase postoperative analgesic requirement in patients receiving preoperative interscalene brachial plexus block (IBP). Sixty-eight patients undergoing arthroscopic shoulder surgery under general anesthesia were randomly allocated to remifentanil (R) or control (C) group. Preoperative IBP with 0.5% ropivacaine 15mL was performed in all patients. Intraoperative remifentanil was administered only in the R group. Postoperative pain was controlled using intravenous patient-controlled analgesia (IV-PCA) and rescue analgesics. The primary outcome was the dosage of fentanyl-nefopam IV-PCA infused over 24h postoperatively. The secondary outcomes included the numeric rating scale (NRS) score recorded at 4-h intervals over 24h, amount of rescue analgesics and total postoperative analgesics used over 24h, occurrence of intraoperative hypotension, postoperative nausea and vomiting (PONV) and delirium. The dosage of fentanyl-nefopam IV-PCA was significantly less in C group than R group for postoperative 24h. Fentanyl 101 [63-158] (median [interquartile range]) µg was used in the C group, while fentanyl 161 [103-285] µg was used in the R group (median difference 64µg, 95% CI 10-121µg, P = 0.02). Nefopam 8.1 [5.0-12.6] mg was used in the C group, while nefopam 12.9 [8.2-22.8] mg was used in the R group (median difference 5.1mg, 95% CI 0.8-9.7mg, P = 0.02). The total analgesic consumption: the sum of PCA consumption and administered rescue analgesic dose, converted to morphine milligram equivalents, was higher in the R group than C group (median difference 10.9mg, 95% CI 3.0-19.0mg, P = 0.01). The average NRS score, the incidence of PONV and delirium, were similar in both groups. The incidence of intraoperative hypotension was higher in R group than C group (47.1% vs. 20.6%, P = 0.005). Remifentanil administration during arthroscopic shoulder surgery in patients undergoing preoperative IBP increased postoperative analgesic consumption.

Analysis of Risk Factors for Intraoperative Hypotension in Cesarean Section and Poor Prognosis of Neonates.

Objective To analyze the risk factors of intraoperative hypotension in cesarean section women and poor prognosis of neonates. Methods The clinical data of 1071 cesarean section women admitted to The Affiliated Jiangning Hospital of Nanjing Medical University from January 2021 to December 2021 were retrospectively analyzed. They were divided into hypotension group (n = 472) and normal control group (n = 599) according to whether there was hypotension during operation. The correlations between the clinical data of cesarean section and the occurrence of intraoperative hypotension and poor prognosis of neonates were analyzed by logistic regression analysis. Receiver operating curve (ROC) was drawn and the area under the curve (AUC) was calculated. Results Logistic regression analysis results showed that BMI ≥30 kg/m2, infant weight ≥3500 g, spinal anesthesia, puncture site L2-3, bupivacaine dose>10 mg, ropivacaine dose>50 mg, and perfusion index≥4 were the risk factor for intraoperative hypotension in cesarean section (p < 0.01) and BMI ≥30 kg/m2, umbilical cord around neck, spinal anesthesia, and perfusion index≥4 were risk factors for poor prognosis of neonates (p < 0.01). The AUC of ROC for BMI to diagnose intraoperative hypotension in cesarean section women was 0.6240 (95% CI: 0.59-0.66, p < 0.01), the sensitivity was only 30.20% (95% CI: 26.73%-35.02%), and the specificity was 87.65% (84.77%-90.04%), and the AUC of BMI for the diagnosis of poor prognosis of neonates was 0.5647 (95% CI: 0.5013-0.6280, p = 0.049), and the sensitivity was 51.19% (95% CI: 40.69%-61.59%), and the specificity was 64.34% (61.30%-67.26%). The AUC of perfusion index for the diagnosis of intraoperative hypotension in cesarean section women was 0.8333 (95% CI: 0.8081-0.8584, p < 0.01), the sensitivity was 94.49% (95% CI: 92.05%-96.21%), and the specificity was 73.12% (69.43%-76.52%); the AUC of perfusion index for the diagnosis of ROC with poor prognosis of neonates was 0.6164 (95% CI: 0.5538-0.6791, p < 0.01), the sensitivity was 70.24% (95% CI: 59.75%-78.96%), and the specificity was 50.86% (47.75%-53.97%). Conclusion The prediction model established by BMI, infant weight, anesthesia method, puncture site, anesthetic drug dose, and perfusion index has guiding value for clinical prediction of cesarean section maternal hypotension. The prediction model established by BMI, umbilical cord around neck, anesthesia method, and perfusion index has guiding value for clinical prediction of poor prognosis of neonates.

Analysis of the Risk Factors for Hypotension in Laparoscopic Hiatal Hernia Repair.

ObjectiveThis study aimed to investigate the risk factors for hypotension in patients undergoing laparoscopic hiatal hernia repair.MethodsThe clinical data of patients who underwent laparoscopic repair of a hiatal hernia in the Beijing Chao-Yang Hospital of Capital Medical University between February 2018 and January 2021 were retrospectively collected, and their perioperative data were obtained by querying the electronic medical record system. The patients were divided into two groups—a hypotension group and a normal group—based on the occurrence of intraoperative hypotension, which was defined as a mean arterial pressure <65 mmHg and lasting ≥1 minute during the operation. The variables with a P value ≤0.1 in univariate regression analysis and clinically considered relevant variables were included in multivariate regression analysis in order to screen the risk factors for hypotension in these patients.ResultsA total of 114 patients were included in the analysis. The incidence of hypotension was 54.4%. Old age was identified as the only risk factor for hypotension during hiatal hernia surgery.ConclusionOld age is the only risk factor for intraoperative hypotension in patients undergoing laparoscopic hiatal hernia repair.

The dynamics of blood pressure within 12 months after carotid artery stenting in patients with stenotic carotid lesions

Aim. To assess the dynamics of blood pressure (BP) and determine the predictors of the hypotensive effect after carotid artery stenting (CAS).Material and methods. The analysis included 99 patients who underwent CAS in a period of March 2014 and May 2016. Inclusion criteria: (1) the presence of 50% symptomatic or 70% asymptomatic stenosis of the carotid artery (according to NASCET criteria), (2) follow-up for at least 1 year, (3) measurement and recording of BP at four points: 24 hours before surgery, 1 hour, 24 hours and 12 months after surgery. Results. According to office measurement of BP, the average systolic/diastolic pressure was 117,11/60,75, 119,73/60,75, 134,75/70,48 mm Hg after 1 hour, one day and 12 months after the intervention, respectively. In comparison with the average numbers of BP before the intervention, 148,13/89,52 mm Hg there was a significantly significant decrease in BP levels after CAS (p&lt;0,01). According to the results of daily monitoring of blood pressure, a statistically important decrease in blood pressure was observed after 1 year of observation (p&lt;0,01) (136,52/76,84 compared with 145,91/87,63 before the intervention). Dissociated circle of Willis (odds ratio=10,37, 95% confidence interval, from 3,64 to 29,52; p&lt;0,001) and the occurrence of intraoperative hypotension (odds ratio =3,62, 95% confidence interval, from 1,16 to 11,28; p&lt;0,027) were predictors of a persistent decrease in BP after CAS. Conclusion. The obtained results indicated the need for more thorough conservative postoperative management, especially for patients with a dissociated circle of Willis. It is also necessary to achieve the target blood pressure values by individualized correction of antihypertensive therapy.

Influence of non-invasive blood pressure measurement intervals on the occurrence of intra-operative hypotension.

The American Society of Anesthesiologists Standards for Basic Monitoring recommends blood pressure (BP) measurement every 5min. Research has shown distractions or technical factors can cause prolonged measurement intervals exceeding 5min. We investigated the relationship between prolonged non-invasive BP (NIBP) measurement interval and the incidence of hypotension, detected post-interval. Our secondary outcome was to determine independent predictors of these prolonged NIBP measurement intervals. Retrospective data were analyzed from 139,509 general anesthesia cases from our institution's Anesthesia Information Management System (AIMS). Absolute hypotension (AH) was defined a priori as a systolic BP < 80mmHg and relative hypotension (RH) was defined as a 40% decrease in systolic BP from the preoperative baseline. Odds ratios (OR) with 95% confidence intervals and Pearson's Chi square Test reported the association of prolonged NIBP measurement intervals on hypotension detected post-NIBP measurement interval. Logistic regression models were developed to determine independent predictors of NIBP measurement intervals. The analysis revealed that NIBP measurement intervals greater than 6 and 10min are associated with an approximately four times higher incidence of a patient transitioning into hypotension (AH/RH > 6min OR 4.0 / 3.6; AH/RH > 10min OR 4.3 / 3.9; p < 0.001). A key finding was that the "> 10-minute AH model" indicated that age 41-80, increased co-morbidity profile, obesity and turning (repositioning) of the operative room table were significant predictors of prolonged NIBP measurement intervals (p < 0.001). While we do not suggest NIBP measurement intervals cause hypotension, intervals greater than 6 and 10min are associated with a fourfold increase in the propensity of an undetected transition into both RH or AH. These data support current monitoring guidelines.

Prone position is associated with mild cerebral oxygen desaturation in elderly surgical patients.

PurposeA variety of hemodynamic and respiratory alterations accompany patients in the prone position; however the effect of the prone position on intraoperative cerebral saturation has not been studied. We sought to examine whether the incidence of cerebral oxygen desaturation in elderly patients (≥68 years of age) undergoing spine surgery in the prone position was more common than patients undergoing major surgery in the supine position.MethodsWe performed a retrospective cohort study of 205 patients; 63 patients underwent surgery in the prone position and 142 in the supine position. Patients were evaluated for cerebral desaturation with bilateral cerebral oximetry. The primary predictor was position, secondary were: length of the surgery, incidence and duration of cerebral desaturation episodes at several thresholds, average time of Bispectral index below threshold of 45 in minutes, average electroencephalogram suppression ratio >0, amount of blood transfused, and the incidence of hypotension and hypertension.ResultsElderly spine surgery patients in the prone position were more than twice as likely to experience mild cerebral desaturation as patients in the supine position. Patients in the prone position had longer surgeries; however cerebral desaturation in the prone position was significantly more common even when adjusted for surgery time and the occurrence of intraoperative hypotension.ConclusionCerebral desaturation is related to the prone position in elderly surgery patients. Future studies are necessary to determine whether this translates to a higher incidence of postoperative cognitive dysfunction and delirium.

Effect of gradient decompression on the occurrence of intraoperative hypotension and prognosis in traumatic brain injury.

To investigate the effect of gradient decompression on the occurrence of intraoperative hypotension and prognosis in traumatic brain injury. A retrospective analysis was performed in 186 hospitalized patients from January, 2008 to January, 2012 in the Affiliated Hospital of Jiangsu University. Demographic data, the abnormality of pupils, and Glasgow Coma Scale (GCS) before operation, and gradient decompression measures, and intraoperative hypotension during operation, and mortality after operation were recorded. Gradient decompression measures were mannitol, hyperventilation, graded craniotomy, and Chi-square test was conducted to evaluate the association of gradient decompression with intraoperative hypotension and prognosis. All the gradient decompression measures were shown non-significantly associated with the occurrence of intraoperative hypotension and prognosis, including mannitol (p=0.852, p=0.328), hyperventilation (p=0.484, p=0.619) and graded craniotomy (p=0.326, p=0.605). Mannitol with hyperventilation (p=0.733, p=0.758), mannitol with graded craniotomy (p=0.319, p=1.000), hyperventilation with graded craniotomy (p=0.269, p=0.685) and all the three measures (p=0.135, p=0.589) were also non-significantly associated with the occurrence of intraoperative hypotension and prognosis. The abnormality of pupils (p=0.006), GCS (p<0.001) and hypotension (p=0.006) were closely associated with the prognosis. Gradient decompression is not effective in avoiding the occurrence of intraoperative hypotension and improving the prognosis. It provides a new insight into clinical measures for curing patients with severe traumatic brain injury (sTBI).

Accusation of Salami publication: the new bane of large database investigations? Young investigators beware!

Accusation of Salami publication: the new bane of large database investigations? Young investigators beware!

Psoas Compartment Block for Acute Postoperative Pain Management After Hip Surgery in Pediatrics

Lower-limb peripheral nerve blocks in pediatrics have gained much more popularity in the last few decades. Our purpose of this study was to compare the postoperative analgesic effects between psoas compartment block (PCB) and caudal block in small children undergoing open hip reduction/osteotomies. Forty American Society of Anesthesiologists physical status I-II children aged 1 to 6 years planned to undergo open hip reduction/osteotomies were administered general anesthesia and then randomly assigned to receive 1 of 2 regional anesthetics: caudal block (group C, n=20) or PCB (group P, n=20). Ropivacaine 0.25% with epinephrine (5 μg/mL) was used in both blocks. The primary outcome of the study was the total consumption of morphine in the first 24 postoperative hrs. Secondary outcomes included dose of intraoperative fentanyl, occurrence of intraoperative hypotension or bradycardia, postoperative pain scores, time to first morphine analgesia, and occurrence of postoperative vomiting or urine retention. The cumulative dose of morphine administered in the ward in the first postoperative 24 hrs and the time to first rescue morphine dose were higher in group C than in group P (P<0.001). There were no differences between the 2 groups regarding intraoperative and postoperative complications except for the incidence of urine retention, which was higher in group C than in group P (P=0.037). Use of single-shot PCB is superior to single-shot caudal block regarding length of postoperative analgesia and cumulative dose of morphine in small children undergoing open hip reduction/osteotomies.

The occurrence of intra‐operative hypotension varies between hospitals: observational analysis of more than 147,000 anaesthesia

Hypotension, a common intra-operative incident, bears an important potential for morbidity. It is most often manageable and sometimes preventable, which renders its study important. Therefore, we aimed at examining hospital variations in the occurrence of intra-operative hypotension and its predictors. As secondary endpoints, we determined to what extent hypotension relates to the risk of post-operative incidents and death. We used the Anaesthesia Databank Switzerland, built on routinely and prospectively collected data on all anaesthesias in 21 hospitals. The three outcomes were assessed using multi-level logistic regression models. Among 147,573 anaesthesias, hypotension ranged from 0.6% to 5.2% in participating hospitals, and from 0.3% up to 12% in different surgical specialties. Most (73.4%) were minor single events. Age, ASA status, combined general and regional anaesthesia techniques, duration of surgery and hospitalization were significantly associated with hypotension. Although significantly associated, the emergency status of the surgery had a weaker effect. Hospitals' odds ratios for hypotension varied between 0.12 and 2.50 (P < or = 0.001), even after adjusting for patient and anaesthesia factors, and for type of surgery. At least one post-operative incident occurred in 9.7% of the procedures, including 0.03% deaths. Intra-operative hypotension was associated with a higher risk of post-operative incidents and death. Wide variations remain in the occurrence of hypotension among hospitals after adjustment for risk factors. Although differential reporting from hospitals may exist, variations in anaesthesia techniques and blood pressure maintenance may also have contributed. Intra-operative hypotension is associated with morbidities and sometimes death, and constant vigilance must thus be advocated.

Severe systemic hypotension during repair of leaking large meningomyelocele

We report a case of a 4-month-old male infant with lumbar meningomyelocele. During surgical repair there was severe systemic hypotension. Though the occurrence of intraoperative hypotension during meningomyelocele repair has been suggested, the exact mechanism remains unknown. While fluid loss is believed to be the main cause of the systemic hypotension, it seems unlikely. We discuss the possible mechanism of the severe hypotension during the intraoperative period in our patient.

Risk factors for intraoperative hypotension in traumatic intracranial hematoma.

Patients suffering from traumatic intracranial hemorrhage (TICH) may experience an episode of catastrophic intraoperative hypotension (IHT), after decompression of the brain. The aim of this study was to investigate the risk factors for IHT during emergency craniotomy A total of 67 patients, who underwent emergency craniotomy due to TICH, were divided into two groups: IHT ( n=31 ) or without IHT ( n=36 ). Data concerning (1) age; (2) gender; (3) mechanism of injury; (4) Glasgow Coma Scale (GCS) on admission; (5) abnormality of the pupils (anisocoria or mydriasis); (6) mean arterial blood pressure; (7) heart rate; (8) time elapsed before craniotomy from injury; (9) initial brain CT scans; (10) duration of craniotomy; and (11) total infusion or urine volume until craniotomy were collected prospectively as IHT risk factors. Low GCS score (<5), tachycardia (heart rate >112min(-1)) and hypertension (mean blood pressure >131mmHg) before emergency craniotomy were strongly ( P<0.05 ) associated with IHT. Delayed surgery (>173min until craniotomy) also had a significant ( P<0.005 ) effect on IHT. The risk factors for IHT were considered as a low GCS score on admission, tachycardia, hypertension before emergency craniotomy and delayed surgery. These results suggested the patients with IHT had a high sympathetic tone before emergency craniotomy A sudden reduction in sympathetic tone after surgical decompression of the brain might cause IHT. We concluded that an important factor in the occurrence of IHT was not only the injury severity, but also the balance between sympathetic and parasympathetic activity before decompression surgery.