Nicardipine versus nitroprusside for deliberate hypotension during idiopathic scoliosis repair

Hemodynamic protective effects of epinephrine containing saline irrigation in biportal endoscopic lumbar surgery

During endoscopic orthopedic surgery, epinephrine mixed with irrigation saline is frequently used to improve visualization. By monitoring hemodynamic parameters throughout the procedure, we intended to discover the hemodynamic effect of epinephrine between the normal saline irrigation fluid without epinephrine group (NS) and normal saline irrigation fluid with epinephrine group (EPI). Patients who underwent 1-level lumbar decompression or discectomy surgery without fusion between August 2019 and July 2020 were reviewed retrospectively. The hemodynamic parameters were compared between the NS group and EPI group. As a second endpoint, the incidence of hypotension and hypertension events, expected blood loss, postoperative nausea and vomiting and postoperative epidural hematoma were compared between the 2 groups. The 2 groups were homogeneous in terms of age, sex, weight, height, body mass index (BMI), ASA physical status (ASA PS), and diagnosis. The incidence of hypotension events (67.2 % in the NS group, 45.7 % in the EPI group, P =.015) and severe hypotension events (51.7 % in the NS group, 28.6 % in the EPI group, P = .015) were less frequent in the EPI group. Only epinephrine had a significant protective effect through a multivariable analysis (P = .027, OR = 2.361) and in severe hypotension events, only epinephrine had a significant protective effect through a multivariable analysis (P = .011, OR = 2.818), and EBL was the risk factor through a multivariable analysis (P = .016, OR = 1.002) We believe that the addition of epinephrine to irrigation saline has hemodynamic protective effects in patients who underwent endoscopic lumbar surgery.

Application of Controlled Hypotension During Surgery for Spinal Metastasis

With advances in tumor treatment, metastasis to bone is increasing, and surgery has become the only choice for most terminal patients. However, spinal surgery has a high risk and is prone to heavy bleeding. Controlled hypotension during surgery has outstanding advantages in reducing intraoperative bleeding and ensuring a clear field of vision, thus avoiding damage to important nerves and vessels. Antihypertensive drugs should be carefully selected after considering the patient's age, different diseases, etc, and a single or combined regimen can be used. Hypotension also inevitably leads to a decrease in perfusion of important organs, so the threshold of hypotension and the maintenance time of hypotension should be strictly limited, and the monitoring of important organs during the operation is particularly important. Information such as blood perfusion, blood oxygen saturation, cardiac output, and neurophysiological conduction potential changes should be obtained in a timely fashion, which will help to reduce the risk of hypotension. In short, when applying controlled hypotension, it is necessary to choose an appropriate threshold and duration, and appropriate monitoring should be conducted during the operation to ensure the safety of the patient.

Sodium nitroprusside versus nicardipine for hypertension management after surgery: A systematic review and meta-analysis

BACKGROUND

Vasoactive medications are commonly administered for afterload reduction and arterial hypertension treatment in patients after cardiac surgery. A systematic review and meta-analysis were conducted to determine the effects of sodium nitroprusside and nicardipine on hemodynamics and cardiac performance in this population.

METHODS

A systematic review of published manuscripts was performed to identify studies of patients who received sodium nitroprusside and nicardipine as part of the treatment for arterial hypertension or afterload reduction after cardiac surgery. A meta-analysis was then conducted to determine the effects of sodium nitroprusside and nicardipine on hemodynamics and cardiac performance. The following parameters were captured: blood pressure, heart rate, right atrial pressure, systemic vascular resistance, and stroke volume.

RESULTS

In total, five studies with 571 patients were pooled for these analyses. Systolic blood pressure, diastolic blood pressure, and mean arterial blood pressure were similar in both groups. The cardiac index was greater with nicardipine while mean pulmonary artery pressure was lower with sodium nitroprusside.

CONCLUSION

Nicardipine and sodium nitroprusside have similar abilities in reducing afterload in the postoperative cardiac population. Statistically significant differences were found in pulmonary artery pressure and cardiac index. It may be beneficial to consider nicardipine for afterload reduction in patients with a low cardiac index.

Comparison of clinical efficacy among remifentanil, nicardipine, and remifentanil plus nicardipine continuous infusion for hypotensive anesthesia during arthroscopic shoulder surgery

PURPOSE

Hypotensive anesthesia is crucial during arthroscopic shoulder surgery to reduce bleeding and allow for clear visibility. The aim of this study was to compare the clinical efficacy of continuous infusion of remifentanil, nicardipine, and remifentanil plus nicardipine to control hypotensive anesthesia in arthroscopic shoulder surgery.

METHODS

For this study, we enrolled 45 consecutive patients who were scheduled to have arthroscopic rotator cuff repair surgery and randomly allocated them into remifentanil (group R, n = 15), nicardipine (group N, n = 15), and remifentanil plus nicardipine (group RN, n = 15) groups. During the surgeries, these drugs were administered with continuous infusion. We analyzed the mean arterial pressure (MAP) and heart rate during surgery, stay time in the recovery room, visual analogue scale (VAS) scores, use of antiemetics in the recovery room, and postoperative blood urea nitrogen and creatinine changes.

RESULTS

The VAS score in the recovery room was higher for group R (mean 5.6, SD 1.4) than for groups N (mean 3.9, SD 0.9) and RN (mean 4.0, SD 1.1; p = 0.000). There were no statistical differences regarding other clinical variables among the three groups (all p > 0.05) except for MAP at 120 min of surgery between groups N and RN (N: 84.67 (SD 10.7) mmHg, RN: 65.4 (SD 9.2) mmHg, p = 0.027).

CONCLUSION

The continuous infusion of remifentanil plus nicardipine appeared to be advantageous for maintaining hypotensive anesthesia until 120 min of arthroscopic shoulder surgery without rebound pain in a postanesthesia care unit.

Effects of vasodilator and esmolol-induced hemodynamic stability on early post-operative cognitive dysfunction in elderly patients: a randomized trial

OBJECTIVE

To investigate the effect of continuous intravenous injection of nicardipine and/or nitroglycerin with or without esmolol on the occurrence of early post-operative cognitive dysfunction (POCD) in elderly patients.

METHODS

Elderly patients (n=340) who underwent radiofrequency ablation for atrial fibrillation were randomized into five groups: A, nicardipine; B nicardipine+esmolol; C, (nitroglycerin) group; D nitroglycerin+esmolol; E (control) groups. The hemodynamic parameters were recorded, and Mini Mental State Examination was used to assess cognitive function.

RESULTS

At 30 min and 60 minutes after anesthesia and at the conclusion of surgery, the rate pressure product value was significantly lower in Groups B (10621.1±321.7, 10544.2±321.8, and 10701.3±325.5, respectively) and D (10807.4±351.1, 10784.3±360.3, and 10771.7±345.7, respectively) than in Group E (13217.1±377.6, 13203.5±357.3, and 13119.2±379.5, respectively). The heart rate was significantly higher in Groups A (104.1±10.3, 104.9±11.1, and 103.9±11.8, respectively) and C (103.7±11.3, 105.5±10.5, and 107.7±11.7, respectively) than in Group E (89.3±12.0, 88.5±11.5, and 85.5±11.6, respectively). The incidence of POCD was significantly lower in Groups A and B than in Groups C, D, and E. Univariate regression analysis showed that regimens in Groups A, B, and E and doses of propofol and fentanyl were risk factors for POCD. Multivariate logistic regression analysis revealed significant associations between the incidence of POCD and interventions in Groups A and B.

CONCLUSION

Maintenance of stable intraoperative hemodynamics using nicardipine and nitroglycerin or their combinations with esmolol, especially nicardipine with esmolol, reduced the incidence of POCD in the elderly with potential cardiovascular diseases.

A prospective, open-label trial of clevidipine for controlled hypotension during posterior spinal fusion

OBJECTIVES

Controlled hypotension is one means to limit or avoid the need for allogeneic blood products. Clevidipine is a short-acting, intravenous calcium channel antagonist with a half-life of 1 to 3 minutes due to rapid metabolism by non-specific blood and tissue esterases. To date, there are no prospective evaluations with clevidipine in the pediatric population. We prospectively evaluated the dosing requirements, efficacy, and safety of clevidipine for ontrolled hypotension during spinal surgery for neuromuscular scoliosis in the pediatric population.

METHODS

Patients undergoing posterior spinal fusion for neuromuscular scoliosis were eligible for inclusion. The study was an open label, observational study. Maintenance anesthesia included desflurane titrated to maintain a bispectral index at 40 to 60 and a remifentanil infusion. Motor and somatosensory evoked potentials were monitored intraoperatively. When the mean arterial pressure (MAP) was ≥ 65 mmHg despite remifentanil at 0.3 mcg/kg/min, clevidipine was added to maintain the MAP at 55 to 65 mmHg. Clevidipine was initiated at 0.25 to 1 mcg/kg/min and titrated up in increments of 0.25 to 1 mcg/kg/min every 3 to 5 minutes to achieve the desired MAP.

RESULTS

The study cohort included 45 patients. Fifteen patients (33.3%) did not require a clevidipine infusion to maintain the desired MAP range, leaving 30 patients including 13 males and 17 females for analysis. These patients ranged in age from 7.9 to 17.4 years (mean ± SD: 13.7 ± 2.2 years) and in weight from 18.9 to 78.1 kg (mean ± SD: 43.4 ± 14.2 kg). Intraoperatively, the clevidipine infusion was stopped in 6 patients as the surgeon expressed concerns regarding spinal cord perfusion and requested a higher MAP than the study protocol allowed. The data until that point were included for analysis. The target MAP was initially achieved at a mean time of 8.9 minutes. Sixteen of the 30 patients (53.3%) achieved the target MAP within 5 minutes. Heart rate (HR) increased from a baseline of 83 ± 16 to 86 ± 15 beats per minute (mean ± SD) (p=0.04) with the administration of clevidipine. No patient had a HR increase ≥ 20 beats per minute or required the administration of a β-adrenergic antagonist. The duration of the clevidipine administration varied from 8 to 527 minutes (mean ± SD: 160 ± 123 minutes). The maintenance infusion rate of clevidipine varied from 0.25 to 5.0 mcg/kg/min (mean ± SD: 1.4 ± 1.1 mcg/kg/min). Clevidipine was paused a total of 43 times in the 30 cases. In 18 of the 30 patients (60%), the clevidipine infusion was temporarily paused more than once due to a MAP < 55 mmHg. A fluid bolus was administered to only 1 patient to treat the low MAP. No patient required the administration of a vasoactive agent for hypotension. When the clevidipine infusion was discontinued as controlled hypotension was no longer required, the MAP returned to baseline or ≥ 65 mmHg within 10 minutes in 12 of the 30 patients (40%).

CONCLUSIONS

Clevidipine can be used to provide controlled hypotension during posterior spinal fusion. The response of the MAP, both the onset and duration of action, were rapid. Although titration of the infusion with occasional pauses of administration may be needed, excessive hypotension was not noted.

Predictors of arterial blood pressure control during deliberate hypotension with sodium nitroprusside in children

BACKGROUND

Sodium nitroprusside (SNP) is used to decrease arterial blood pressure (BP) during certain surgical procedures. There are limited data regarding efficacy of BP control with SNP. There are no data on patient and clinician factors that affect BP control. We evaluated the dose-response relationship of SNP in infants and children undergoing major surgery and performed a quantitative assessment of BP control.

METHODS

One hundred fifty-three subjects at 7 sites received a blinded infusion followed by open-label SNP during operative procedures requiring controlled hypotension. SNP was administered by continuous infusion and titrated to maintain BP control (mean arterial BP [MAP] within ±10% of clinician-defined target). BP was recorded using an arterial catheter. Statistical process control methodology was used to quantify BP control. A multivariable model assessed the effects of patient and procedural factors.

RESULTS

BP was controlled an average 45.4% (SD 23.9%; 95% CI, 41.5%-49.18%) of the time. Larger changes in infusion rate were associated with worse BP control (7.99% less control for 1 μg·kg·min increase in average titration size, P = 0.0009). A larger difference between a patient's baseline and target MAP predicted worse BP control (0.93% worse control per 1-mm Hg increase in MAP difference, P = 0.0013). Both effects persisted in multivariable models.

CONCLUSIONS

SNP was effective in reducing BP. However, BP was within the target range less than half of the time. No clinician or patient factors were predictive of BP control, although 2 inverse relationships were identified. These relationships require additional study and may be best coupled with exposure-response modeling to propose improved dosing strategies when using SNP for controlled hypotension in the pediatric population.

Sodium nitroprusside is not associated with metabolic acidosis during intraoperative infusion in children

BACKGROUND

Sodium nitroprusside (SNP) is a potent vasodilator that has been used to induce deliberate hypotension in children during surgery involving significant blood loss, including craniofacial and spinal fusion procedures. SNP metabolism liberates cyanide, which may cause interference with cellular energy metabolism, leading to metabolic acidosis and central nervous system injury. We performed a retrospective, case-control study to determine whether the short-term intra-operative use of SNP for deliberate hypotension is associated with metabolic acidosis in children undergoing surgical procedures for craniofacial or spinal anomalies. Cyanide and thiocyanate concentrations were also recorded in patients who received SNP.

METHODS

Data from 166 children undergoing craniofacial and spinal fusion surgery between 2005 and 2010 at Lucile Packard Children's Hospital (LPCH) at Stanford were analyzed. Records from 60 patients who received SNP (SNP group) as part of a multicenter, randomized, double-blind study were compared with records from 106 eligible patients who had blood pressure reduction using anesthetic agents and did not receive SNP (control group). Metabolic acidosis was defined as serum bicarbonate (HCO3) < 18.5 mEq/L. Whole blood CN, plasma thiocyanate and urinary thiocyanate concentrations were measured in patients in the SNP group. Differences in metabolic acidosis rates between the SNP and control groups were assessed through a test of noninferiority in the rate for the SNP group with a noninferiority threshold of 0.2. A z-test was used to test the null hypothesis. The alternative hypothesis was that the difference in these rates was less than 0.2. The same noninferiority threshold of 0.2 was also used to perform separate, secondary tests for noninferiority in the proportion of patients with HCO3 levels below 18.5 mEq/L and the proportion of patients who required HCO3 administration.

RESULTS

Fewer patients in the SNP group experienced metabolic acidosis compared to the control group (31.7% vs. 36.8%, respectively; p < .001). No whole blood CN levels above the lower limit of quantification were detected in any of the 51 patients with validated CN data. Plasma and urinary thiocyanate levels were also low.

CONCLUSIONS

Our findings suggest that SNP, when used for short-term deliberate hypotension, does not cause an increased incidence of metabolic acidosis compared with the use of anesthetic agents alone.

TRIAL REGISTRATION

TRIAL REGISTRATION NUMBER

NCT00135668.

Nitroglycerin and sodium nitroprusside: potential contributors to postoperative bleeding?

Postoperative bleeding is common in patients undergoing cardiac surgery with cardiopulmonary bypass. Most cases of severe postoperative bleeding not due to incomplete surgical hemostasis are related to acquired transient platelet dysfunction mediated by platelet activation during contact with the synthetic surfaces of the cardiopulmonary bypass equipment. Antihypertensive agents nitroglycerin and sodium nitroprusside have been shown to have platelet inhibitory properties, yet the clinical consequence in terms of postoperative bleeding has been little studied. Knowing that cardiopulmonary bypass causes platelet dysfunction, it is prudent for physicians to be aware of the additional platelet inhibition caused by these commonly used antihypertensive agents.

The hemodynamic changes during the infusion of remifentanil for patients under sevoflurane anesthesia during arthroscopic shoulder surgery

BACKGROUND

In spite of its minimal invasiveness, hemodynamic instability frequently happens during arthroscopic procedures. This study was performed to investigate the clinical efficacy of remifentanil for controlling the intra-operative hemodynamics during the performance of arthroscopic shoulder surgery.

METHODS

Sixty patients (ASA class 1 and 2) who were scheduled for arthroscopic shoulder surgery were recruited for this study. After the induction and maintenance of anesthesia with thiopental sodium, rocuronium bromide, sevoflurane and nitrous oxide, the patients were randomly allocated to receive either saline or three different doses of remifentanil (0.03, 0.05 or 0.07 microg/kg/min) to assess the hemodynamic changes such as the systolic blood pressure, the diastolic blood pressure and the heart rate.

RESULTS

The hemodynamics in the remifentanil groups were more stable than those in the saline group (P < 0.05), but there were some cardiovascular side effects such as hypertension (remifentanil 0.03 microg/kg/min), hypotension and bradycardia (remifentanil 0.07 microg/kg/min) with using remifentanil.

CONCLUSIONS

Remifentanil 0.05 microg/kg/min under anesthetic maintenance with sevoflurane showed better hemodynamic stability than the other two remifentanil groups during arthroscopic shoulder surgery.

Greater peripheral blood flow but less bleeding with propofol versus sevoflurane during spine surgery: a possible physiologic model?

STUDY DESIGN

Prospective, randomized, single blind.

OBJECTIVE

To compare the effects of sevoflurane and propofol on lumbar-paraspinal-muscles regional blood flow, as well as bleeding when controlled hypotension is used.

SUMMARY OF BACKGROUND DATA

Controlled hypotension is the technique of choice to reduce blood loss during spine surgery, but changes in blood flow occurring to lumbar paraspinal muscles during controlled hypotension with propofol and sevoflurane, as well as the entity of bleeding, are unknown.

METHODS

Blood flow was assessed by means of a laser Doppler flowmeter during the prehypotensive and hypotensive (defined as a 15% reduction of baseline mean arterial pressure) period in 28 patients (aged 28-73 years, American Society of Anesthesiologists (ASA) I-II) undergoing lumbar spine surgery. Patients were randomized to receive either sevoflurane or propofol as main anesthetic agent to achieve hypotension. At the end of the surgery, blood loss was calculated and intraoperative bleeding (Visual Analogue Scale ranging from 0 to 100) was evaluated by the surgeon. RESULTS.: Peripheral Blood flow was significantly greater in the propofol group both before and during the hypotensive period (median values of 32.7 FU vs. 7.7 and 38.5 FU vs. 10.5, respectively). Despite this fact, blood loss and intraoperative bleeding were significantly reduced when propofol had been used (P < 0.05).

CONCLUSION

Despite the greater blood flow when it is used, propofol causes less bleeding than sevoflurane during spine surgery and could be more indicated to produce hypotension during anesthesia. Moreover, it is possible to explain our findings hypothesizing a selective vasodilation of propofol (postcapillary, venous vasodilation), different from that of sevoflurane (precapillary, arteriolar vasodilation).

Intravenous Nicardipine

Nicardipine is a water soluble calcium channel antagonist, with predominantly vasodilatory actions. Intravenous (IV) nicardipine (Cardene IV), which demonstrates a relatively rapid onset/offset of action, is used in situations requiring the rapid control of blood pressure (BP). IV nicardipine was as effective as IV nitroprusside in the short-term reduction of BP in patients with severe or postoperative hypertension. A potential role for IV nicardipine in the intraoperative acute control of BP in patients undergoing various surgical procedures (including cardiovascular, neurovascular and abdominal surgery), and in the deliberate induction of reduced BP in surgical procedures in which haemostasis may be difficult (e.g. surgery involving the hip or spine) was demonstrated in preliminary studies. Preliminary studies also indicated the ability of a bolus dose of IV nicardipine to attenuate the hypertensive response, but not the increase in tachycardia, after laryngoscopy and tracheal intubation in anaesthetised patients. In large, well designed studies, IV nicardipine prevented cerebral vasospasm in patients with recent aneurysmal subarachnoid haemorrhage; however, overall clinical outcomes at 3 months were similar to those in patients who received standard management. Small preliminary studies have investigated the use of IV nicardipine in a variety of other settings, including acute intracerebral haemorrhage, acute ischaemic stroke, pre-eclampsia, acute aortic dissection, premature labour and electroconvulsive therapy.In conclusion, the efficacy of IV nicardipine in the short-term treatment of hypertension in settings for which oral therapy is not feasible or not desirable is well established. The ability to titrate IV nicardipine to the tolerance levels of individual patients makes this agent an attractive option, especially in critically ill patients or those undergoing surgery. Potential exists for further investigation of the use of this agent in clinical settings where a vasodilatory agent with minimal inotropic effects is appropriate.

Old method, new drugs: comparison of the efficacy of sevoflurane, isoflurane, and desflurane in achieving controlled hypotension in spinal surgery

This study compared the efficacy of isoflurane, sevoflurane, and desflurane in achieving hemodynamic stability in spinal procedures using moderate levels of controlled hypotension. After obtaining ethics committee approval and written informed consent, 32 American Surgical Association I-II patients were randomly allocated to receive isoflurane (n=12), sevoflurane (n=10), or desflurane (n=10) in O2-N2O (1:1) for maintenance of anesthesia. The induction of anesthesia, fentanyl dosage, and initial and maintenance volume replacements were standardized. Blood pressure was invasively monitored and maintained within a target systolic blood pressure (SBP) range of 80 to 90 mm Hg during the study. SBP outside this range was recorded. Volatile anesthetic concentration was adjusted according to the same protocol for all 3 agents. SPB control was maintained better with sevoflurane and isoflurane than desflurane; median SBP was outside the target range during 32% (range, 15%-55%) of study time with isoflurane, 26% (12%-42%) with sevoflurane, and 44% (20%-80%) with desflurane. Total blood loss did not differ among the groups. Sevoflurane and isoflurane administered in 2 L/min fresh gas flow were more effective than desflurane in achieving controlled hypotension in spinal surgery.