Profound Hypotension Research Articles

Oculographic analysis of nystagmus in orthostatic vertigo

Oculographic analysis of nystagmus in orthostatic vertigo

Intraoperative Anaphylaxis Secondary to Intraosseous Gelatin Administration

FloSeal and SurgiFlo Hemostatic Matrices are commonly used in surgical procedures to promote coagulation and minimize blood loss. They are composed of bovine and porcine gelatin matrix, respectively, that can be injected into pedicles to stop osseous bleeding during pedicle screw insertion. This report details 2 pediatric spinal deformity reconstructive surgery patients who experienced intraoperative cardiovascular events after the intraosseous administration of animal-derived gelatin. Case #1 is an 11-year-old female with adolescent idiopathic scoliosis who was undergoing routine posterior spinal instrumentation and fusion. During placement of the fourth pedicle screw, the patient developed profound hypotension, tachycardia, and elevated airway pressures requiring intravenous epinephrine and phenylephrine for hemodynamic support. Surgery was aborted. Postoperative work-up demonstrated a positive ImmunoCAP study for bovine gelatin. Surgery was repeated 1 week later, without the use of FloSeal, and no episodes of hemodynamic instability. Case #2 was a 9-year-old female with juvenile idiopathic scoliosis who was undergoing a growing spine construct. As in Case #1, SurgiFlo was placed into 2 pedicle tracts after which there was profound hypotension, tachycardia, and elevated airway pressures. Resuscitative efforts included intravenous atropine and epinephrine with resolution. Surgery was aborted. Surgery was repeated 2 weeks later, without the use of SurgiFlo, with no episodes of hemodynamic instability. Given that the patient's symptoms were classic for anaphylaxis, and that the timing of the anaphylaxis immediately followed the administration of FloSeal and SurgiFlo we believe that FloSeal and SurgiFlo were the causes of the reactions. These are the first known reported cases of intraoperative anaphylaxis associated with FloSeal and SurgiFlo. On the basis of our experience, in order to avoid intraoperative cardiovascular events, we obtain preoperative ImmunoCAP testing and eliciting a thorough preoperative history about bovine-derived and porcine-derived gelatin products.

Kounis syndrome: ST elevation and anaphylaxis

SummaryWe present a case of sudden, dramatic ST elevation followed by profound hypotension at induction of anaesthesia. This was subsequently confirmed as anaphylaxis with acute coronary involvement (Kounis syndrome) by tryptase and troponin assays. This case illustrates the variable presentation of anaphylaxis, the limitations of our current understanding of this condition and the importance of clinical judgment in balancing the management of two pathologies.

Use of an Impedance Threshold Device to Treat Severe Hypotension in a Pregnant Woman: Case Report and Review of the Literature

BackgroundImpedance threshold device technology harnesses the patient's normal physiological mechanisms to increase circulation during hypotensive crises. We report the first clinical use of one version of this device on a spontaneously breathing hypotensive pregnant woman. ObjectiveThe objective of our study was to report this case to help Emergency Medical Service rescue personnel to noninvasively treat hypotensive but conscious spontaneously breathing patients. Case ReportA 28-year-old woman who was 21 weeks pregnant developed frank syncope at home but recovered spontaneously. When Emergency Medical Service paramedics arrived, her initial blood pressure and heart rate were 115/80 mm Hg and 125 beats/min, respectively. She suddenly complained of feeling anxious and developed profound bradycardia and hypotension, followed by 20 s of asystole. An impedance threshold device (ResQGARDTM) with −7 cmH2O resistance to inspiration was rapidly applied using a facemask. After four spontaneous breaths, blood pressure increased from 62/40 mm Hg to 106/66 mm Hg. She was hemodynamically stable thereafter. ConclusionsIn this case report, the multiple physiological effects of inspiration through −7 cmH2O resistance helped this pregnant hypotensive patient to rapidly and noninvasively restore adequate perfusion and reduced the duration of her hypotensive episode. To our knowledge, this is the first report of this technology in a pregnant hypotensive but spontaneously breathing patient.

Self-expanding polyurethane polymer improves survival in a model of noncompressible massive abdominal hemorrhage

Intracavitary noncompressible hemorrhage remains a significant cause of preventable death on the battlefield. Two dynamically mixed and percutaneously injected liquids were engineered to create an in situ self-expanding polymer foam to facilitate hemostasis in massive bleeding. We hypothesized that intraperitoneal injection of the polymer could achieve conformal contact with sites of injury and improve survival in swine with lethal hepatoportal injury. High grade hepatoportal injury was created in a closed abdominal cavity, resulting in massive noncoagulopathic, noncompressible hemorrhage. Animals received either standard battlefield fluid resuscitation (control, n = 12) or fluid resuscitation plus intraperitoneal injection of hemostatic foam (polymer, n = 15) and were monitored for 3 hours. Blood loss was quantified, and all hepatoportal injuries were inspected for consistency. Before intervention, all animals initially experienced severe, profound hypotension and near-arrest (mean arterial pressure at 10 minutes, 21 [5.3] mm Hg). Overall survival at 3 hours was 73% in the polymer group and 8% in the control group (p = 0.001). Median survival time was more than 150 minutes in the polymer group versus 23 minutes (19-41.5 minutes) in the control group (p < 0.001), and normalized blood loss in the polymer group was 0.47 (0.30) g/kg per minute versus 3.0 (1.3) g/kg per minute in the controls (p = < 0.001). All hepatoportal injuries were anatomically similar, and the polymer had conformal contact with injured tissues. Intraperitoneal polymer injection during massive noncompressible hemorrhage reduces blood loss and improves survival in a lethal, closed-cavity, hepatoportal injury model. Chronic safety and additional efficacy studies in other models are needed.

Profound Hypotension After Anesthetic Induction with Propofol in Patients Treated with Rifampin

Rifampin is commonly used for the treatment of tuberculosis and staphylococcal infections, as well as for prevention of infection in cardiac valve and bone surgeries. We report a case of profound hypotension after anesthesia induction with propofol in a patient who was treated with two 600 mg doses of rifampin for prophylaxis of infection before surgery. In a retrospective case-control study of 75 patients, we confirmed this potentially serious drug-drug interaction. After rifampin, there was a significant and prolonged arterial blood pressure reduction when patients received propofol, but not thiopental.

Dynamic cerebral autoregulation of the posterior cerebral artery after high level spinal cord injury

It has been reported that those with high level (e.g., &gt;; T5) spinal cord injury (HLSCI) can tolerate profound hypotension in the absence of syncopal symptoms. Altered dynamic cerebral autoregulation (dCA) may help maintain cerebral blood flow (CBF) and improve tolerance to hypotension. In HLSCI, dCA of the posterior cerebral artery (PCA), which is relevant to syncopal episodes due to its supply arising from arteries perfusing the brainstem (i.e., critical region for maintaining consciousness), has not been investigated. Eight complete HLSCI and eight matched controls (AB) were examined in the upright position. Five‐minute long recordings of spontaneously occurring beat‐to‐beat changes in blood pressure (BP; photoplethysmography) as well as velocity in the middle cerebral artery (MCA) and PCA (transcranial Doppler) were recorded. To provide insight into dCA, transfer function analysis was performed to evaluate coherence, gain and phase of the MCA and PCA in the very low (0.02–0.07 Hz) and low (0.07–0.2 Hz) frequency ranges. In HLSCI, BP‐MCAv coherence was reduced by 33% in both the LF and VLF range, while VLF phase was reduced by 63% (P &lt; 0.05). Similarly, BP‐PCAv coherence was reduced by 48% in the LF and 54% in the VLF range (P &lt; 0.01). These results show that CBF regulation is altered in both the MCA and PCA in those with HLSCI.

Rapid Respiratory Failure after Heart Transplant

Introduction Strongyloides is a helminthic intestinal parasite that is common in tropical regions. In immunosuppressed individuals it may cause a hyperinfection syndrome with fatal complications. We present one such case. Case Report A 60 year old Hispanic male presents 2 months after heart transplantation (HT) with fatigue. His post transplant course was complicated by recurrent rejection requiring intravenous steroids. His immunosuppression included tacrolimus, mycophenolate mofetil and prednisone. On presentation, he underwent endomyocardial biopsy which demonstrated 1R rejection. Echocardiography revealed normal allograft function. He developed respiratory distress requiring intubation, followed by profound hypotension necessitating vasopressor and broad spectrum antimicrobial support. Due to difficulty with oxygenation, he underwent urgent bronchoscopy. Over the next 72 hours, he became increasingly unstable. On hospital day 4, Papanicolaou staining identified Strongyloides in the bronchoalveolar lavage specimen. [ figure 1 ] Ivermectin 200mg was initiated and on hospital day 7 with the patient continuing to do poorly, albendazole was added. This resulted in improvement in his hemodynamic and respiratory status, however, his mental status failed to recover. Lumbar puncture revealed Strongyloides in the cerebro-spinal fluid. On hospital day 26 life sustaining support was withdrawn and the patient passed away. Summary Atypical symptoms and rapid deterioration in HT patients without a clear cause should prompt an early investigation for strongyloides. Screening of high risk populations, such as those from endemic areas, of both potential donors and recipients should be discussed as pre-treatment may prevent catastrophic complications.

Treatment of acute inferior wall myocardial infarction and ruptured abdominal aortic aneurysm: A hybrid approach

A 64-year-old male patient was admitted to our emergency department with chest pain, profound hypotension and poor general condition. The initial electrocardiogram showed ST-segment elevation in leads DII, DIII and aVF with complete heart block. He was rapidly transferred to the catheterization laboratory for primary percutaneous intervention of the infarct-related artery. Initially, the right femoral artery was used for the arterial access site. During the advancement of the guide-wire, however, an unusual course apart from the route of the abdominal aorta was observed. The wire turned toward the right side of the patient at the level of the kidneys. Contrast injection demonstrated a huge aneurysmal dilation and slight blushing of the contrast agent at this level. The right radial artery was cannulated for the continuation of the procedure. Aortic root and proximal descending aortagraphy showed no aneurysm or dissection however, at the infra-renal level, previously detected huge aneurysmal dilation and slight blushing of the contrast agent were shown again (Movie 1). Meanwhile, a distal total occlusion of the right coronary artery was detected (Movie 2). Time-consuming left coronary system angiography was not performed. After emergent consultation with the department of cardiovascular surgery, a hybrid interventional procedure was decided. Accordingly, a direct bare-metal stent (4.0×12 mm) implantation to the right coronary artery was first performed with achievement of TIMI 3 flow and without administration of a thienopyridine drug or glycoprotein IIb/IIIa inhibitor agent (Movie 3). A single-dose of aspirin (300 mg) given in the emergency room and 5000 IU of unfractionated heparin were the only drugs administrated. After reperfusion, ST-segment resolution and sinus rhythm were obtained. The patient was then referred to operating room and standard aorta-bifemoral bypass surgery with a synthetic aortic Y-graft was applied for the treatment of ruptured abdominal aortic aneurysm. The oral thienopyridine drug, clopidogrel (75 mg/d), and aspirin (300 mg/d) were started after achieving hemostasis at the 3rd day postoperatively. Control angiography was performed at the 30th day postoperatively. Previously deployed stent was patent (Fig. 1a ) and no important stenosis was detected on the left coronary circulation. In addition, patent aorta-bifemoral Y-graft was demonstrated (Fig. 1b).

Anesthetic Management for Resection of Hepatic Paraganglioma Metastatic From the Donor Organ in an Orthotopic Liver Transplant Recipient: A Case Report

This is a case report of the anesthetic management for the hepatic resection of a metastatic paraganglioma in a patient with a history of prior orthotopic liver transplantation. Of interest, the metastatic paraganglioma originated from the donor organ. The patient is an 80-year-old woman with multiple medical problems including a history of cryptogenic cirrhosis who underwent successful orthotopic liver transplantation 9 years prior. She later presented with signs and symptoms of catecholamine excess suggestive of a catecholamine-producing tumor (paraganglioma or pheochromocytoma). Elevated urine catecholamine levels and radiographic evidence of a paraganglioma in the transplanted liver metastatic from the donor organ confirmed the diagnosis. Radiofrequency ablation of the tumor and surgical resection was previously attempted without success. We describe the anesthetic management for the successful resection of the metastatic hepatic paraganglioma, which was complicated by profound intraoperative hypertension and hypotension that necessitated the use of multiple vasoactive infusions, extensive surgical blood loss requiring blood transfusion, and difficult glycemic control in an insulin-dependent diabetic patient. The postoperative course is also described. This unique case presented the anesthesia team with challenges specific to both surgery for hepatic resection as well as for catecholamine-secreting tumors. We are not aware of any reports of paragangliomas of either donor or recipient origin involving a transplanted liver, making this the first such report to the best of our knowledge.

Multimodal Approach to Pain Management Following Bipolar Hemiarthroplasty for Femoral Neck Fracture: I’m a Believer!

The multimodal approach to pain management has been enthusiastically embraced in the hope that the undesirable side effects and consequences of traditional reliance on narcotic medications can be overcome. Orthopaedic surgical procedures are painful. Postsurgical pain has well-documented negative consequences, and poorly controlled postoperative pain not only slows recovery but also leads to unacceptable levels of patient dissatisfaction. In the past two decades, techniques of continuous infusion of narcotics partially controlled by the patient either by an intravenous route or through the continuation of the epidural route after surgery has been very successful in helping to manage postoperative pain. Epidural patient-controlled anesthesia is especially attractive for lower-extremity surgery because narcotics can be mixed with local anesthetics, lowering the dose and toxicity of the narcotic while achieving very dramatic pain control. Unfortunately, this excellent control of pain has unwanted consequences. Patients who experience satisfactory pain relief when using epidural patient-controlled anesthesia often require a urinary catheter, experience nausea presumably from the epidural narcotic, and have relatively profound postural hypotension that limits their …

Association between plasma cyclic guanosine monophosphate levels and hemodynamic instability during liver transplantation

The activation of cyclic guanosine monophosphate (cGMP) production in patients with end-stage liver disease (ESLD) has been associated with hemodynamic instability during orthotopic liver transplantation (OLT). The aim of this prospective, observational study was to investigate the involvement of cGMP in the mediation of profound hypotension during liver graft reperfusion. An additional objective was to determine whether preoperative cGMP levels are associated with intraoperative hemodynamic instability. Forty-four consecutive patients undergoing OLT were included in the study. Blood samples for cGMP analysis were obtained from (1) the radial artery before the surgical incision; (2) the radial artery, portal vein, and flush blood during the anhepatic phase; and (3) the radial artery 20 minutes after liver graft reperfusion. On the basis of a statistical analysis, the patients were divided into 2 groups: group 1 (preoperative cGMP level ≥ 0.05 μmol/L) and group 2 (preoperative cGMP level < 0.05 μmol/L). We demonstrated a significant correlation between the preoperative levels of cGMP and the amount of catecholamine required to maintain hemodynamic stability during reperfusion (r = 0.52, P < 0.001), the length of the hospital stay (r = 0.38, P = 0.01), and the length of the intensive care unit (ICU) stay (r = 0.44, P = 0.004). We also demonstrated a significantly higher intraoperative catecholamine requirement (P < 0.001) and a prolonged postoperative ICU stay (P = 0.02) in group 1 patients versus group 2 patients. In conclusion, this study demonstrates increased baseline cGMP production in patients with ESLD, which is significantly associated with severe hypotension during OLT. We suggest that preoperative levels of cGMP correlate with hemodynamic instability during liver graft reperfusion.

Effects of a TREM-Like Transcript 1–Derived Peptide During Hypodynamic Septic Shock in Pigs

The objective of this study was to determine the effects of a TREM (triggering receptor expressed on myeloid cells 1)-like transcript 1-derived peptide (LR12) administration during septic shock in pigs. Two hours after induction of a fecal peritonitis, anesthetized and mechanically ventilated adult male minipigs were randomized to receive LR12 (n = 6) or its vehicle alone (normal saline, n = 5). Two animals were operated and instrumented without the induction of peritonitis and served as controls (sham). Resuscitation was achieved using hydroxyethyl starch (up to 20 mL/kg) and norepinephrine infusion (up to 10 μg/kg per minute). Hemodynamic parameters were continuously recorded. Gas exchange, acid-base status, organ function, and plasma cytokines concentrations were evaluated at regular intervals until 24 h after the onset of peritonitis when animals were killed under anesthesia. Peritonitis induced profound hypotension, myocardial dysfunction, lactic acidosis, coagulation abnormalities, and multiple organ failure. These disorders were largely attenuated by LR12. In particular, cardiovascular failure was dampened as attested by a better mean arterial pressure, cardiac index, cardiac power index, and S(v)O(2), despite lower norepinephrine requirements. LR12, a TREM-like transcript 1-derived peptide, exhibits salutary properties during septic shock in adult minipigs.

An Unusual Cause of Acute Cardiogenic Shock in the Operating Room

A 51-year-old man with a renal carcinoma with inferior vena cava (IVC) invasion was referred to our hospital for the performance of a radical nephrectomy with IVC thrombus excision. To prevent embolism, an IVC filter was implanted the day before surgery below the suprahepatic veins. On nephrectomy completion, the clinical status of the patient started to deteriorate and an unsuccessful attempt was made to excise the IVC thrombus. The patient developed profound refractory hypotension without significant bleeding and worsening splanchnic stasis was noted. A transesophageal echocardiogram was immediately performed in the operating room, revealing a hemispheric mass protruding from the IVC ostium to the right atrium, completely blocking all venous return. Volume depletion was evident by low left and right atrial volumes and increased septum mobility. No other abnormalities were found that could explain the shock, namely ventricular dysfunction or valvular disease. Cardiac surgery consultation was immediately obtained, ultimately deciding to perform a median sternotomy with direct exploration of right atrium. Under cardiopulmonary bypass, a 6-cm long thrombotic mass was identified, involving the IVC filter, blocking all lower body venous return; the removal of the mass reversed the shock. The patient had an uneventful recovery. Adverse outcomes associated with IVC filters are common. Our case highlights the importance of a team approach to rapid changes in hemodynamic status in the operating room, including the surgeon, the anesthesiologist, and the cardiologist. It also emphasizes the pivotal role of transesophageal echocardiogram in the clinical evaluation of severely unstable patients.

Salusins: Potential Use as a Biomarker for Atherosclerotic Cardiovascular Diseases

Human salusin-α and salusin-β are related peptides produced from prosalusin. Bolus injection of salusin-β into rats induces more profound hypotension and bradycardia than salusin-α. Central administration of salusin-β increases blood pressure via release of norepinephrine and arginine-vasopressin. Circulating levels of salusin-α and salusin-β are lower in patients with essential hypertension. Salusin-β exerts more potent mitogenic effects on human vascular smooth muscle cells (VSMCs) and fibroblasts than salusin-α. Salusin-β accelerates inflammatory responses in human endothelial cells and monocyte-endothelial adhesion. Human macrophage foam cell formation is stimulated by salusin-β but suppressed by salusin-α. Chronic salusin-β infusion into apolipoprotein E-deficient mice enhances atherosclerotic lesions; salusin-α infusion reduces lesions. Salusin-β is expressed in proliferative neointimal lesions of porcine coronary arteries after stenting. Salusin-α and salusin-β immunoreactivity have been detected in human coronary atherosclerotic plaques, with dominance of salusin-β in macrophage foam cells, VSMCs, and fibroblasts. Circulating salusin-β levels increase and salusin-α levels decrease in patients with coronary artery disease. These findings suggest that salusin-β and salusin-α may contribute to proatherogenesis and antiatherogenesis, respectively. Increased salusin-β and/or decreased salusin-α levels in circulating blood and vascular tissue are closely linked with atherosclerosis. Salusin-α and salusin-β could be candidate biomarkers and therapeutic targets for atherosclerotic cardiovascular diseases.

Long lasting neurocardiogenic reflex provoked by emotional trigger

A 53-year-old man presented with a protracted presyncope and profound hypotension and bradycardia due to emotion related vasovagal reaction. Electrocardiogram obtained 20 minutes after the onset of presyncope revealed junctional rhythm at 38 beats per minute (bpm). After supination, clinical symptoms and hemodynamic disturbances immediately resolved. Careful cardiologic evaluation revealed significant stenosed coronary vessels. Maintaining the vertical position may be responsible for persistent bradycardia and hypotension after neurocardiogenic reflex provocation.

Profound Hypotension after an Intradermal Injection of Indigo Carmine for Sentinel Node Mapping

Intradermal injections of indigo carmine for sentinel node mapping are considered safe and no report of an adverse reaction has been published. The authors described two cases of profound hypotension in women that underwent breast-conserving surgery after an intradermal injection of indigo carmine into the periareolar area for sentinel node mapping.

Erroneous blood pressure readings in a patient with Multiple Hereditary Exostoses

SummaryA 15 year old male with Multiple Hereditary Exostoses (MHE) developed what appeared to be profound hypotension shortly after induction of anaesthesia. All other clinical parameters, including skin color, breath sounds, heart rate, peripheral pulses, oxygen saturation and end‐tidal carbon dioxide were normal. When the cuff of the automated blood pressure device was removed and reapplied elsewhere, the blood pressure reading was normal. Examination of the original location of the cuff revealed an exostosis on the medial aspect of the proximal humerus, which had prevented the automated blood pressure device from detecting the pulsation of the artery. Had a preoperative examination of the limb been done, it may have resulted in using a different location for blood pressure monitoring, and prevented the erroneous readings. Additional issues of concern to the anaesthetist in patients with Multiple Hereditary Exostoses are discussed.

Unraveling Pharmacokinetics and Pharmacodynamics in Infants and Children

Our knowledge of the pharmacology of the drugs used in pediatric anesthesia has advanced with a greater understanding of their pharmacokinetics (PK) and pharmacodynamics. This has resulted in a refinement of their uses, broader indications, and alternative methods of delivery. For example, methadone is becoming increasingly popular for spinal surgery, the dosing of etomidate has been clarified and the PK of intravenous acetaminophen from neonates to adults has been revealed. Morphine PK have also been clarified, although pharmacodynamic ethnic differences remain unexplained. The optimal size descriptor to predict correct drug doses in the obese remains controversial. Efforts to reduce adverse effects of individual drugs have spawned investigations into beneficial drug interactions, although combinations such as propofol and ketamine await PK and safety review. The nasal route may be a reasonable alternative to intravenous administration for many drugs. Oral ketamine may serve as a valuable premedication for children suffering burns. Expanded indications can have unfavorable consequences; propofol may cause profound hypotension in neonates.

Haemodynamic effects from aortocaval compression at different angles of lateral tilt in non-labouring term pregnant women

Aortocaval compression (ACC) can result in haemodynamic disturbances and uteroplacental hypoperfusion in parturients. Its detection is difficult because in most patients, sympathetic compensation results in no signs or symptoms. However, profound hypotension may develop after sympathectomy during regional anaesthesia. In this prospective observational study, we aimed to detect ACC by analysing haemodynamic changes in term parturients who were positioned sequentially at different angles of lateral tilt. We studied haemodynamic changes in 157 non-labouring term parturients who were positioned in random order at 0°, 7.5°, 15°, and full left lateral tilt. Cardiac output (CO), stroke volume, and systemic vascular resistance were derived using suprasternal Doppler. Non-invasive arterial pressure (AP) measured in the upper and lower limbs was analysed to detect aortic compression. CO was on average 5% higher when patients were tilted at ≥15° compared with <15°. In a subgroup of patients (n=11), CO decreased by more than 20%, without changes in systolic AP, when they were tilted to <15° which was considered attributable to severe inferior vena caval compression. Only one patient in the supine position had aortic compression with the systolic AP in the upper limb 25 mm Hg higher than the lower limb. Patients with ACC can be identified by the CO changes from serial measurements between supine, 15°, or full lateral tilt. Our findings suggest that in non-labouring parturients, ACC is asymptomatic and can be effectively minimized by the use of a left lateral tilt of 15° or greater.