Antifibrinolytics Are Not Associated With Reduced Blood Loss in Minimally-Invasive Endoscopic-Assisted Craniectomy for Repair of Single-Suture Craniosynostosis.

ABSTRACT: Minimally-invasive endoscopic-assisted craniectomy (EAC) achieves similar functional and cosmetic outcomes, whereas reducing morbidity risk that is often associated with complex cranial vault reconstruction. Antifibrinolytics (AF) usage to limit blood loss and transfusion requirements during complex cranial vault reconstruction has been studied extensively; however, studies are limited for AF therapy in EAC. The aim of this single-center retrospective observational cohort pilot study was to evaluate whether the use of AF was associated with reduced blood loss in infants undergoing EAC. The authors hypothesized that there would be no difference in blood loss between patients who received AF and those that did not receive AF during EAC. Non-syndromic patients who underwent single-suture EAC were retrospectively evaluated. Primary outcome measure was intraoperative calculated blood loss (mL/kg). Secondary outcome measures included perioperative red blood cells transfusion volumes, number of blood donor exposures, and pediatric intensive care unit and total hospital length of stay. Study cohort demographic and outcome data were analyzed; Fisher exact test was used for categorical data, Student t test was used for continuous data. A P value of <0.05 was considered statistically significant. Forty-nine EAC patients were included in the study with 34 patients in the AF cohort and 15 patients in the non-AF cohort. There were no significant differences in demographics between the 2 groups. Additionally, there was no significant difference in intraoperative calculated blood loss or any secondary outcome measure. In our single-suture EAC study cohorts, AF administration was not associated with a decrease in blood loss when compared to those that did not receive AF therapy.

ε-Aminocaproic acid versus tranexamic acid in children undergoing complex cranial vault reconstruction for repair of craniosynostosis.

Complex cranial vault reconstruction (CCVR) for pediatric craniosynostosis is a high blood loss surgery, for which antifibrinolytic agents have been shown to reduce bleeding and transfusion requirements. The relative efficacy of ε-aminocaproic acid (EACA) versus tranexamic acid (TXA) has not yet been evaluated in this population. The aim of this retrospective study was to compare perioperative blood loss and transfusion in CCVR patients receiving EACA versus TXA. In a CCVR cohort of 95 children, 47 received EACA and 48 received TXA. We found no differences in demographics, adverse outcomes, calculated blood loss (CBL), or transfusion requirements between the two antifibrinolytic groups.

Hemodynamic Parameters in the Assessment of Fluid Status in a Porcine Hemorrhage and Resuscitation Model.

BACKGROUND: Measuring fluid status during intraoperative hemorrhage is challenging, but detection and quantification of fluid overload is far more difficult. Using a porcine model of hemorrhage and over-resuscitation, it is hypothesized that centrally obtained hemodynamic parameters will predict volume status more accurately than peripherally obtained vital signs. METHODS: Eight anesthetized female pigs were hemorrhaged at 30 ml/min to a blood loss of 400 ml. After each 100 ml of hemorrhage, vital signs (heart rate, systolic blood pressure, mean arterial pressure, diastolic blood pressure, pulse pressure, pulse pressure variation) and centrally obtained hemodynamic parameters (mean pulmonary artery pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac output) were obtained. Blood volume was restored, and the pigs were over-resuscitated with 2,500 ml of crystalloid, collecting parameters after each 500-ml bolus. Hemorrhage and resuscitation phases were analyzed separately to determine differences among parameters over the range of volume. Conformity of parameters during hemorrhage or over-resuscitation was assessed. RESULTS: During the course of hemorrhage, changes from baseline euvolemia were observed in vital signs (systolic blood pressure, diastolic blood pressure, and mean arterial pressure) after 100 ml of blood loss. Central hemodynamic parameters (mean pulmonary artery pressure and pulmonary capillary wedge pressure) were changed after 200 ml of blood loss, and central venous pressure after 300 ml of blood loss. During the course of resuscitative volume overload, changes were observed from baseline euvolemia in mean pulmonary artery pressure and central venous pressure after 500-ml resuscitation, in pulmonary capillary wedge pressure after 1,000-ml resuscitation, and cardiac output after 2,500-ml resuscitation. In contrast to hemorrhage, vital sign parameters did not change during over-resuscitation. The strongest linear correlation was observed with pulmonary capillary wedge pressure in both hemorrhage (r2 = 0.99) and volume overload (r2 = 0.98). CONCLUSIONS: Pulmonary capillary wedge pressure is the most accurate parameter to track both hemorrhage and over-resuscitation, demonstrating the unmet clinical need for a less invasive pulmonary capillary wedge pressure equivalent.

Financial and Clinical Ramifications of Introducing a Novel Pediatric Enhanced Recovery After Surgery Pathway for Pediatric Complex Hip Reconstructive Surgery.

BACKGROUND: Enhanced recovery after surgery pathways confer significant perioperative benefits to patients and are currently well described for adult patients undergoing a variety of surgical procedures. Robust data to support enhanced recovery pathway use in children are relatively lacking in the medical literature, though clinical benefits are reported in targeted pediatric surgical populations. Surgery for complex hip pathology in the adolescent patient is painful, often requiring prolonged courses of opioid analgesia. Postoperative opioid-related side effects may lead to prolonged recovery periods and suboptimal postoperative physical function. Excessive opioid use in the perioperative period is also a major risk factor for the development of opioid misuse in adolescents. Perioperative opioid reduction strategies in this vulnerable population will help to mitigate this risk. METHODS: A total of 85 adolescents undergoing complex hip reconstructive surgery were enrolled into an enhanced recovery after surgery pathway (October 2015 to December 2018) and were compared with 110 patients undergoing similar procedures in previous years (March 2010 to September 2015). The primary outcome was total perioperative opioid consumption. Secondary outcomes included hospital length of stay, postoperative nausea, intraoperative blood loss, and other perioperative outcomes. Total cost of care and specific charge sectors were also assessed. Segmented regression was used to assess the effects of pathway implementation on outcomes, adjusting for potential confounders, including the preimplementation trend over time. RESULTS: Before pathway implementation, there was a significant downward trend over time in average perioperative opioid consumption (-0.10 mg total morphine equivalents/90 days; 95% confidence interval [CI], -0.20 to 0.00) and several secondary perioperative outcomes. However, there was no evidence that pathway implementation by itself significantly altered the prepathway trend in perioperative opioid consumption (ie, the preceding trend continued). For postanesthesia care unit time, the downward trend leveled off significantly (pre: -5.25 min/90 d; 95% CI, -6.13 to -4.36; post: 1.04 min/90 d; 95% CI, -0.47 to 2.56; Change: 6.29; 95% CI, 4.53-8.06). Clinical, laboratory, pharmacy, operating room, and total charges were significantly associated with pathway implementation. There was no evidence that pathway implementation significantly altered the prepathway trend in other secondary outcomes. CONCLUSIONS: The impacts of our pediatric enhanced recovery pathway for adolescents undergoing complex hip reconstruction are consistent with the ongoing improvement in perioperative metrics at our institution but are difficult to distinguish from the impacts of other initiatives and evolving practice patterns in a pragmatic setting. The ERAS pathway helped codify and organize this new pattern of care, promoting multidisciplinary evidence-based care patterns and sustaining positive preexisting trends in financial and clinical metrics.

Physiology and clinical utility of the peripheral venous waveform.

The peripheral venous system serves as a volume reservoir due to its high compliance and can yield information on intravascular volume status. Peripheral venous waveforms can be captured by direct transduction through a peripheral catheter, non-invasive piezoelectric transduction, or gleaned from other waveforms such as the plethysmograph. Older analysis techniques relied upon pressure waveforms such as peripheral venous pressure and central venous pressure as a means of evaluating fluid responsiveness. Newer peripheral venous waveform analysis techniques exist in both the time and frequency domains, and have been applied to various clinical scenarios including hypovolemia (i.e. hemorrhage, dehydration) and volume overload.

A brief report on the effects of vasoactive agents on peripheral venous waveforms in a porcine model.

OBJECTIVES: Non-invasive venous waveform analysis (NIVA) is a recently described, novel technique to assess intravascular volume status. Waveforms are captured with a piezoelectric sensor; analysis in the frequency domain allows for calculation of a "NIVA value" that represents volume status. The aim of this report was to determine the effects of vasoactive agents on the venous waveform and calculated NIVA values. DESIGN: Porcine experimental model. SETTING: Operating theatre. PARTICIPANTS: A piezoelectric sensor was secured over the surgically exposed saphenous vein in eight anesthetized pigs. MAIN OUTCOME MEASURES: NIVA value, pulmonary capillary wedge pressure (PCWP), and mean arterial pressure prior to and post intravenous administration of 150-180 µg of phenylephrine or 100 µg of sodium nitroprusside. RESULTS: Phenylephrine led to a decrease in NIVA value (mean 9.2 vs. 4.6, p < 0.05), while sodium nitroprusside led to an increase in NIVA value (mean 9.5 vs. 11.9, p < 0.05). Mean arterial pressure increased after phenylephrine (p < 0.05) and decreased after sodium nitroprusside (p < 0.05). PCWP did not change significantly after phenylephrine (p = 0.25) or sodium nitroprusside (p = 0.06). CONCLUSIONS: Vasoactive agents lead to changes in non-invasively obtained venous waveforms in euvolemic pigs, highlighting a potential limitation in the ability to NIVA to estimate static volume in this setting. Further studies are indicated to understand the effects of vasoactive agents in the setting of hypovolemia and hypervolemia.

Non-Invasive Venous waveform Analysis (NIVA) for volume assessment during complex cranial vault reconstruction: A proof-of-concept study in children.

BACKGROUND: Non-Invasive Venous waveform Analysis (NIVA) is novel technology that captures and analyzes changes in venous waveforms from a piezoelectric sensor on the wrist for hemodynamic volume assessment. Complex cranial vault reconstruction is performed in children with craniosynostosis and is associated with extensive blood loss, potential life-threatening risks, and significant morbidity. In this preliminary study, we hypothesized that NIVA will provide a reliable, non-invasive, quantitative assessment of intravascular volume changes in children undergoing complex cranial vault reconstruction. OBJECTIVE: To present proof-of-concept results of a novel technology in the pediatric population. METHODS: The NIVA prototype was placed on each subject's wrist, and venous waveforms were collected intraoperatively. Estimated blood loss and fluid/blood product administration were recorded in real time. Venous waveforms were analyzed into a NIVA value and then correlated, along with mean arterial pressure (MAP), to volume changes. Concordance was quantified to determine if the direction of change in volume was similar to the direction of change in MAP or change in NIVA. RESULTS: Of 18 patients enrolled, 14 had usable venous waveforms, and there was a significant correlation between change in NIVA value and change in volume. Change in MAP did not correlate with change in volume. The concordance between change in MAP and change in volume was less than the concordance between change in NIVA and change in volume. CONCLUSION: NIVA values correlate more closely to intravascular volume changes in pediatric craniofacial patients than MAP. This initial study suggests that NIVA is a potential safe, reliable, non-invasive quantitative method of measuring intravascular volume changes for children undergoing surgery.

Successful utilisation of epidural analgesia for perioperative pain management in a child with sodium voltage-gated channel alpha subunit (SCN1A) gene mutation.

Sodium voltage-gated channel alpha subunit (SCN1A) gene mutation is a rare disorder with a large spectrum of clinical presentations. Little is known regarding anaesthetic and analgesic management of these patients. We present a case of a child with SCN1A gene mutation that was successfully managed with an epidural for perioperative analgesia for an abdominal surgery.

Pediatric Electroconvulsive Therapy: An Anesthesiologist's Perspective.

Proper planning and communication between psychiatry and anesthesiology teams is vital to conferring the greatest therapeutic benefit to children presenting for electroconvulsive therapy while minimizing risk. Anesthesia for the child undergoing electroconvulsive therapy should ideally provide deep hypnosis, ensure muscle relaxation to reduce injury, have minimal effect on seizure dynamics, and allow for rapid recovery to baseline neurologic and cardiopulmonary status. Unique factors for pediatric electroconvulsive therapy include the potential need for preoperative anxiolytic and inhalational induction of anesthesia, which must be weighed against the detrimental effects of anesthetic agents on the evoked seizure quality required for a successful treatment.

Anesthetic considerations for pediatric electroconvulsive therapy.

Electroconvulsive therapy is being used more frequently in the treatment of many chronic and acute psychiatric illnesses in children. The most common psychiatric indications for pediatric electroconvulsive therapy are refractory depression, bipolar disorder, schizophrenia, catatonia, and autism. In addition, a relatively new indication is the treatment of pediatric refractory status epilepticus. The anesthesiologist may be called upon to assist in the care of this challenging and vulnerable patient population. Unique factors for pediatric electroconvulsive therapy include the potential need for preoperative anxiolytic and inhalational induction of anesthesia, which must be weighed against the detrimental effects of anesthetic agents on the evoked seizure quality required for a successful treatment. Dexmedetomidine is likely the most appropriate preoperative anxiolytic as oral benzodiazepines are relatively contraindicated. Methohexital, though becoming less available at many institutions, remains the gold standard for induction of anesthesia for pediatric electroconvulsive therapy though ketamine, propofol, and sevoflurane are becoming increasingly viable options. Proper planning and communication between the multidisciplinary teams involved in the care of children presenting for electroconvulsive therapy treatments is vital to mitigating risks and achieving the greatest therapeutic benefit.