Susceptibility of optic nerve head in children with posture-related elevation of intraocular pressure

BACKGROUND/AIMS

This work aimed to investigate changes in optic nerve head (ONH) morphometry based on Bruch membrane opening in children with extensive nocturnal intraocular pressure (IOP) elevations.

METHODS

The course of Bruch membrane opening-based optic nerve head (ONH) morphometry was analysed in thirty-two patients younger than 18 years with evaluable SD-OCT examinations of the ONH and nocturnal posture-dependent IOP elevation above 25 mmHg. Longitudinal changes in neuroretinal rim tissue, as measured by Bruch Membrane opening minimum rim width (BMO-MRW) and peripapillary retinal nerve fiber layer (RNFL) thickness, were assessed.

RESULTS

One year after the 24 h IOP measurement, global BMO-MRW (- 1.61 ± 16.8 µm, n.s.; p = 0.611) and RNFL (+ 0.64 ± 3.17 µm; n.s.; p = 0.292) measurements were not significantly different from the baseline. No significant BMO-MRW reduction (- 3.91 ± 24.3 µm; n.s. p = 0.458) or deviation in RNFL thickness (+ 1.10 ± 3.52 µm) was observed at the four-year follow-up. Absolute IOP values measured in the supine position did not correlate with changes in global BMO-MRW or RNFL thickness.

CONCLUSION

Posture-dependent IOP elevations do not seem to influence retinal nerve fibre layer thickness or Bruch membrane opening-based morphometric data in childhood.

Posture-related fluctuations of intraocular pressure in healthy children with suspicion of glaucoma

PURPOSE

Currently, there are no specific data on the circadian course of intraocular pressure (IOP) in children, especially for IOP measurements in the supine position. The study aimed to characterize the diurnal and nocturnal IOP fluctuations in supine and sitting positions in patients less than 18 years of age.

METHODS

Seventy-nine eyes of 79 patients under 18 years of age with suspicious optic nerve heads or ocular hypertension could be included in this study. All included patients showed an inconspicuous retinal nerve fiber layer thickness and Bruch's membrane minimum rim width by coherence tomography. IOP measurements during the 24-h IOP profile were retrospectively evaluated. Measurements were taken at 10:00, 16:00, 20:00, and 23:00 h in the sitting position and at 6:00 h in the morning in the supine position using iCare rebound tonometry on 2 consecutive days.

RESULTS

Thirty-four of 79 children (43.0%) had peak nocturnal IOP values > 25 mmHg. The mean daily IOP was 18.8 ± 5.6 mmHg, and the mean daily fluctuation was 6.1 ± 4.0 mmHg. At 6 am, supine measurements were elevated to 25.1 ± 8.0 mmHg. Extensive fluctuations with values > 40 mmHg in the nocturnal supine measurement occurred in a relevant share of patients (n = 5).

CONCLUSION

There appear to be relevant diurnal and nocturnal IOP fluctuations in healthy children (< 18 years). Nocturnal IOP measurements in supine patients with risk factors for glaucoma may provide important additional information to identify critical patients for further follow-up.

[Revision of the PRESERFLO® MicroShunt with ologen and mitomycin C]

Bleb failure after implantation of filtering stents (e.g. Preserflo Stent) is a frequent challenge in glaucoma surgery that has occurred in recent years. In the following, a technique for open bleb revision with mitomycin C (0.2 mg/ml) and ologen implantation is presented, which is intended to re-establish the filtration volume lost due to fibrosis and a long-term preservation.

New platelet functional method for identification of pathogenic antibodies in HIT patients

Heparin-induced thrombocytopenia (HIT) is a thrombotic complication of heparin therapy. The most used functional method for HIT diagnosis is serotonin release assay (SRA). A different functional method based on ATP release with luciferin/luciferase long-life and stable luminescent signal is used here, which is shown to be comparable for accuracy with SRA in both negative (patients 4Ts ≤3, and negative for both anti-PF4/heparin immunoassay and SRA) and positive (4Ts >3, and positive for both PF4/heparin antibodies and SRA) patients. Our results show that ATP release is higher in washed platelets activated by sera from positive patients than in platelets activated by sera from negative patients. In conclusion, we demonstrate that ATP release assay is a valid alternative method to SRA for the identification of pathogenic anti-PF4/heparin antibodies.

Mechanical circulatory support in advanced heart failure: single-center experience

BACKGROUND

Currently, ventricular assist device (VAD) or total artificial heart (TAH) mechanical support provides an effective treatment of unstable patients with advanced heart failure. We report our single-center experience with mechanical circulatory support therapy.

METHODS

From March 2002 to December 2012, 107 adult patients (mean age, 56.8 ± 9.9 y; range, 31-76 y) were primarly supported on temporary or long-term VAD or TAH support as treatment for refractory heart failure at our institution. Temporary extracorporeal radial VAD support (group A) was established in 49 patients (45.7%), and long-term paracorporeal and intracorporeal VAD or TAH (group B) in 58 patients (54.2%). Left ventricular (LVAD) support was established in 55 patients (51.4%; n = 33, Heartmate II; n = 6, Heartmate I XVE; n = 4, Heartware HVAD; and n = 12, Centrimag) and biventricular (BVAD/TAH) support (group B) in 28 patients (26.1%; n = 10, Thoratec paracorporeal; n = 2, Heartware HVAD, n = 1, Thoratec implantable; n = 1, Syncardia TAH; and n = 14, Centrimag). The temporary Centrimag was the only device adopted as isolated right ventricular (RVAD) support, and it was inserted in 24 patients (22.4%).

RESULTS

In group A, overall mean support time was 10.2 ± 6.6 days (range, 3-43 d). In group B, LVAD mean support time was 357 ± 352.3 days (range, 1-902 d) and BVAD/TAH support time was 98 ± 82.6 days (range, 8-832 d). In group A, the overall success rate was 55.1% (27 patients). In group B, LVAD overall success rate was 74.4% (32 patients) and BVAD/TAH success rate was 50% (7 patients). Overall heart transplantation rate for both groups was 27.1% (n = 2, group A; n = 27, group B). Overall 1-year and 5-year survivals after heart transplantation were 72.4% (n = 21) and 58.6% (n = 17), respectively.

CONCLUSIONS

Mechanical circulatory support is an effective strategy even in cases of end-stage heart failure according to our experience. Further improvement of VAD and TAH technologies may support their adoption as an encouraging alternative to heart transplantation in the near future.

High rate of colistin resistance among patients with carbapenem-resistant Klebsiella pneumoniae infection accounts for an excess of mortality

Carbapenem-resistant Klebsiella pneumoniae (CR-KP) is becoming a common cause of healthcare-associated infection in Italy, with high morbidity and mortality. Prevalent CR-KP clones and resistance mechanisms vary between regions and over time. Therapeutic approaches and their impact on mortality have to be investigated. We performed a prospective study of patients with CR-KP isolation, hospitalized in nine hospitals of Rome, Italy, from December 2010 to May 2011, to describe the molecular epidemiology, antibiotic treatment and risk factors for mortality. Overall, 97 patients (60% male, median age 69 years) were enrolled. Strains producing blaKPC-3 were identified in 89 patients, blaVIM in three patients and blaCTX-M-15 plus porin defects in the remaining five patients. Inter-hospital spread of two major clones, ST512 and ST258, was found. Overall, 36.1% and 20.4% of strains were also resistant to colistin and tigecycline, respectively. Infection was diagnosed in 91 patients who received appropriate antibiotic treatment, combination therapy and removal of the infectious source in 73.6%, 59.3% and 28.5% of cases, respectively. Overall, 23 different antibiotic regimens were prescribed. In-hospital mortality was 25.8%. Multivariate analysis adjusted for appropriate treatment, combination therapy and infectious-source removal, showed that Charlson comorbidity score, intensive-care unit onset of infection, bacteraemia and infection due to a colistin-resistant CR-KP strain were independent risk factors for mortality. The spread of clones producing K. pneumoniae carbapenemases, mainly ST258, is currently the major cause of CR-KP infection in central Italy. We observed a high rate of resistance to colistin that is independently associated with worse outcome.

Treatment with daptomycin for Corynebacterium Jeikeium left-sided prosthetic valve endocarditis

Prosthetic valve endocarditis (PVE) is a serious complication with potential fatal consequences, classified as early or late PVE, depending on whether typical symptoms occur within or later than 12 months from surgery. The incidence of early PVE is under 1%, but it carries high morbidity and mortality rates. There are few reported cases in literature of PVE due to Corynebacterium Jeikeium even though it is present in normal skin flora particularly in hospitalized patients. Corynebacterium species are, in fact, recognized as uncommon agents of endocarditis and little is known regarding species-specific risk factors and the outcome in this kind of endocarditis. Described is an unusual case report of a 57-year-old man who had early aortic PVE due to Corynebacterium Jeikeium infection complicated by dehiscence of the prosthesis, complete atrio-ventricular block, perforation of the interventricular septum and septic shock. Prompt diagnosis, choice of daptomycin as antibiotic therapy although it has only been approved by the European Medicine Agency (EMEA) for right-sided endocarditis and timely open heart surgery, resulted in a successful outcome.

An alternative inexpensive treatment for deep sternal wound infections after sternotomy

We present three cases of deep sternal wound infections after sternotomy, with partial dehiscence and instability of sternum, successfully treated with combined therapy based on hyperbaric oxygen (HBO), parenteral and intranasal antibiotics, daily debridements and medications. After a short hospitalization (10 days) to detect involved bacteria, depth of the wounds and choice of right antibiotic therapy, all patients continued the treatment as outpatients, undergoing daily medications and antibiotic therapy before every HBO session. After 3 months the sternal wounds were completely epithelialized. This conservative therapy for deep sternal wound infections can be an alternative and inexpensive approach to surgical treatment. The aggressive surgical approach could be limited for those deep sternal wounds associated with broad dehiscence and instability of sternum, complicated by paradoxical breathing and/or mediastinitis and alteration of respiratory system mechanics.

Successful treatment of a complicated case of neuroleptic malignant syndrome

Neuroleptic malignant syndrome (NMS) is a life-threatening reaction often related to neuroleptic drugs, characterized by rigidity, hyperthermia, altered consciousness, and fluctuating blood pressure. We present a case of NMS that followed a doubled oral dose of a drug compound: tranylcypromine sulfate, a monoamine oxidase inhibitor, and trifluoperazine (neuroleptic). The case was complicated by rhabdomyolisis and disseminated intravascular coagulation. It was treated successfully with dantrolene sodium and generous fluid therapy without using neuromuscular blocking agents or dopamine agonists.

Noninvasive ventilation for treatment of acute respiratory failure in patients undergoing solid organ transplantation: a randomized trial

CONTEXT

Noninvasive ventilation (NIV) has been associated with lower rates of endotracheal intubation in populations of patients with acute respiratory failure.

OBJECTIVE

To compare NIV with standard treatment using supplemental oxygen administration to avoid endotracheal intubation in recipients of solid organ transplantation with acute hypoxemic respiratory failure.

DESIGN AND SETTING

Prospective randomized study conducted at a 14-bed, general intensive care unit of a university hospital.

PATIENTS

Of 238 patients who underwent solid organ transplantation from December 1995 to October 1997, 51 were treated for acute respiratory failure. Of these, 40 were eligible and 20 were randomized to each group.

INTERVENTION

Noninvasive ventilation vs standard treatment with supplemental oxygen administration.

MAIN OUTCOME MEASURES

The need for endotracheal intubation and mechanical ventilation at any time during the study, complications not present on admission, duration of ventilatory assistance, length of hospital stay, and intensive care unit mortality.

RESULTS

The 2 groups were similar at study entry. Within the first hour of treatment, 14 patients (70%) in the NIV group, and 5 patients (25%) in the standard treatment group improved their ratio of the PaO2 to the fraction of inspired oxygen (FIO2). Over time, a sustained improvement in PaO2 to FIO2 was noted in 12 patients (60%) in the NIV group, and in 5 patients (25%) randomized to standard treatment (P = .03). The use of NIV was associated with a significant reduction in the rate of endotracheal intubation (20% vs 70%; P = .002), rate of fatal complications (20% vs 50%; P = .05), length of stay in the intensive care unit by survivors (mean [SD] days, 5.5 [3] vs 9 [4]; P = .03), and intensive care unit mortality (20% vs 50%; P = .05). Hospital mortality did not differ.

CONCLUSIONS

These results indicate that transplantation programs should consider NIV in the treatment of selected recipients of transplantation with acute respiratory failure.

Prolonged mivacurium-induced neuromuscular block. Case report

A 38-year-old white male patient was admitted to the hospital for elective surgery. General anesthesia was performed with propofol, alfentanil, nitrous oxide and mivacurium as neuromuscular blocker. Seven months before he had the same surgery without anesthetic problems (he received: propofol, vecuronium bromide, fentanil, nitrous oxide). Neuromuscular monitoring was carried out because the patient was included in a study assessing the clinical effect of mivacurium in microlaryngoscopy surgery. After mivacurium administration the first signs of recovery from neuromuscular block were observed after 255 min. The tracheal tube was withdrawn after 410 min from mivacurium administration, at this time the T1 was 80% of the control values and 7 min later the T1 reached 98%.

Noninvasive ventilation for the treatment of acute respiratory failure in patients with hematologic malignancies: a pilot study

OBJECTIVE

To evaluate treatment with noninvasive ventilation (NIV) by nasal mask as an alternative to endotracheal intubation and conventional mechanical ventilation in patients with hematologic malignancies complicated by acute respiratory failure to decrease the risk of hemorrhagic complications and increase clinical tolerance.

DESIGN

Prospective clinical study.

SETTING

Hematologic and general intensive care unit (ICU), University of Rome "La Sapienza".

PATIENTS

16 consecutive patients with acute respiratory failure complicating hematologic malignancies.

INTERVENTIONS

NIV was delivered via nasal mask by means of a BiPAP ventilator (Respironics, USA); we evaluated the effects on blood gases, respiratory rate, and hemodynamics along with tolerance, complications, and outcome.

MEASUREMENTS AND RESULTS

15 of the 16 patients showed a significant improvement in blood gases and respiratory rate within the first 24 h of treatment. Arterial oxygen tension (PaO2), PaO2/FIO2 (fractional inspired oxygen) ratio, and arterial oxygen saturation significantly improved after 1 h of treatment (43+/-10 vs 88+/-37 mmHg; 87+/-22 vs 175+/-64; 81+/-9 vs 95+/-4%, respectively) and continued to improve in the following 24 h (p < 0.01). Five patients died in the ICU following complications independent of the respiratory failure, while 11 were discharged from the ICU in stable condition after a mean stay of 4.3+/-2.4 days and were discharged in good condition from the hospital.

CONCLUSIONS

NIV by nasal mask proved to be feasible and appropriate for the treatment of respiratory failure in hematologic patients who were at high risk of intubation-related complications.

Comparative evaluation of the cardiorespiratory effects of assist control ventilation vs pressure support ventilation in patients following orthotopic liver transplantation

OBJECTIVE

1) To compare the haemodynamic tolerance of ACV and PSV in patients mechanically ventilated after orthotopic liver transplantation; 2) to compare patients comfort during ACV and PSV.

DESIGN

Prospective randomized cross-over study.

SETTING

General ICU of the University of Rome "La Sapienza".

PATIENTS

Eighteen patients admitted in ICU after orthotopic liver transplantation.

MEASUREMENT AND RESULTS

Haemodynamic, oxygen transport and blood gas data were compared during an ACV and PSV trial (30'). A statistically significant decrease of mean pulmonary and systemic arterial pressure, PCOP, LVSWI, occurred during the PSV trial. PaO2 and DO2I decreased during PSV, but were still in supranormal range; 16 out of 18 patients described PSV as more comfortable.

CONCLUSIONS

ACV and PSV provided a comparable haemodynamic tolerance in our patients, although during PSV the PaO2 was slightly decreased, probably due to decreased mean airway pressure (from 9.3 +/- 1.2 cmH2O during ACV to 6.6 +/- 1 cmH2O during PSV). PSV can be considered as a good alternative to the standard weaning techniques following orthotopic liver transplantation.

Respiratory system mechanics in the early phase of acute respiratory failure due to severe kyphoscoliosis

OBJECTIVE

To evaluate respiratory mechanics in the early phase of decompensation in a group of seven patients with severe kyphoscoliosis (KS) (Cobb angle > 90 degrees) requiring mechanical ventilatory support.

DESIGN

Prospective clinical study with a control group.

SETTING

General intensive care unit at University of Rome "La Sapienza".

PATIENTS

Seven consecutive patients affected by severe KS in the early phase of acute decompensation and a control group of six ASA (American Society of Anesthesiology) 1 subjects who were mechanically ventilated during minor surgery.

MEASUREMENTS AND RESULTS

Respiratory mechanics were evaluated during constant flow-controlled mechanical ventilation at zero end-expiratory pressure with the end-inspiratory and end-expiratory occlusion technique. In five patients who showed increased ohmic resistance (RRSmin), we evaluated the possibility of reversing this increase with a charge dose of 6 mg/kg doxophylline i.v. In four KS patients, in whom a reliable esophageal pressure was confirmed by a positive occlusion test, we separated respiratory system data into lung and chest wall component. All KS patients showed reduced values of respiratory compliance (CRS) and increased respiratory resistance (RRS). The average basal values of CRS were 36 +/- 10 vs 58 +/- 8.5 cmH2O in control patients; RRSmax was 20 +/- 3.1 vs. 4.5 +/- 1.2 cmH2O/1 per s; RRSmin 6.2 +/- 1.2 vs. 2 +/- 0.5 cmH2O/1 per s: delta RRS 14 +/- 2.6 cmH2O vs 2.4 +/- 0.7 cmH2O/1 per s. All KS patients showed low values of intrinsic positive end-expiratory pressure (PEEPi) (1.8 +/- 1.5 cmH2O). Separation of lung and chest-wall mechanics, performed only in four patients, showed a reduction in both lung (66.7 +/- 7.2 ml/cmH2O) and chest wall values (84 +/- 8.2 ml/cmH2O), while both RmaxL and RmaxCW were increased (16.6 +/- 2 and 2.8 +/- 0.4 cmH2O/1 per s, respectively). Infusion of doxophylline did not significantly change respiratory mechanics when evaluated 15, 30, and 45 min after the infusion.

CONCLUSIONS

During acute decompensation, both lung and chest-wall compliance are severely reduced in KS patients: conversely, and, contrary to that in patients with chronic obstructive pulmonary disease, increases in airway resistance and PEEPi seem to play only a secondary role.

Effect of low dose fentanyl-droperidol administration on respiratory drive, respiratory pattern and gas exchange in ASA 1 spontaneously breathing patients

The aim of this study was to investigate the short term effects of low doses of fentanyl and droperidol on central respiratory drive, gas exchanges, respiratory pattern and inspiratory impedance of the respiratory system in a group of ASA 1 patients. Fourteen ASA 1 patients scheduled for minor surgery or endoscopic procedures were enrolled in the study, thirty minutes before the intervention. During spontaneous breathing of air we evaluated, by recording airflow, airway opening pressure and volume, the following variables: Respiratory Rate (RR), Tidal Volume (TV), Total respiratory cycle, Inspiratory and Expiratory Time (Ti, Te), mean inspiratory flow, P0.1, pH, PaO2 and PaCO2. After obtaining basal measurements, droperidol and fentanyl were injected and the above mentioned variables evaluated at 5 min (T1), 10 min (T2), 15 min (T3) intervals. Arterial blood was age, sampled at T3 for blood gas evaluation. The administration of droperidol (0.1 mg/kg) and fentanyl (0.002 mg/kg) significantly reduced P0.1 and Tidal Volume comparing basal with T1 and, T2 values. The other variables did not significantly modify. Two patients showed transient respiratory rhythm abnormalities in the first 180 sec following the administration of droperidol+fentanyl. Our results suggest that, in ASA 1 patients, droperidol+fentanyl preoperative administration, has no significant effects on respiratory pattern, respiratory impedance and gas exchanges: however also at low doses, the association of droperidol+fentanyl can reduce the respiratory center activity, expressed as P0.1, with a consequent reduction in Tidal Volume.

Paralysis has no effect on chest wall and respiratory system mechanics of mechanically ventilated, sedated patients

OBJECTIVE

To evaluate the separate effects of sedation and paralysis on chest wall and respiratory system mechanics of mechanically ventilated, critically ill patients.

SETTING

ICU of the University "La Sapienza" Hospital, Rome.

PATIENTS AND PARTICIPANTS

13 critically ill patients were enrolled in this study. All were affected by disease involving both lungs and chest wall mechanics (ARDS in 4 patients, closed chest trauma without flail chest in 4 patients, cardiogenic pulmonary oedema with fluidic overload in 5 patients).

MEASUREMENTS AND RESULTS

Respiratory system and chest wall mechanics were evaluated during constant flow controlled mechanical ventilation in basal conditions (i.e. with the patients under apnoic sedation) and after paralysis with pancuronium bromide. In details, we simultaneously recorded airflow, tracheal pressure, esophageal pressure and tidal volume; with the end-inspiratory and end-expiratory airway occlusion technique we could evaluate respiratory system and chest wall elastance and resistances. Lung mechanics was evaluated by subtracting chest wall from respiratory system data. All data obtained in basal conditions (with the patients sedated with thiopental or propofol) and after muscle paralysis were compared using the Student's t test for paired data. The administration of pancuronium bromide to sedated patients induced a complete muscle paralysis without producing significant modification both to the viscoelastic and to the resistive parameters of chest wall and respiratory system.

CONCLUSIONS

This study demonstrates the lack of additive effects of muscle paralysis in mechanically ventilated, sedated patients. Also in view of the possible side effects of muscle paralysis, our results question the usefulness of generalized administration of neuromuscular blocking drugs in mechanically ventilated patients.

A new device to remove obstruction from endotracheal tubes during mechanical ventilation in critically ill patients

OBJECTIVE

To evaluate the efficiency of a new device developed to remove obstructions from endotracheal tubes (ETT) in mechanically ventilated patients.

DESIGN

Open study in mechanically ventilated sedated and paralyzed ICU patients.

SETTING

General ICU and Laboratory of Respiratory Mechanics of the University of Rome "La Sapienza".

PATIENTS

8 consecutive unselected mechanically ventilated, critically ill patients in which a partial obstruction of ETT was suspected on the basis of an increase of the peak inspiratory pressure (> 20%) plus the difficult introduction of a standard suction catheter.

INTERVENTIONS

Obstructions to ETT were removed with an experimental "obstruction remover" (OR) MEASUREMENTS: "In vivo" ETT airflow resistance (0.25; 0.5; 0.75; 11/s) was evaluated before and after use of the OR; the work of breathing necessary to overcome ETT resistance (WOBett) was also evaluated before and after OR use.

RESULTS

The use of OR significantly reduced in all patients the ETT "in vivo" resistance (From 5.5 +/- 2.3 to 2.9 +/- 0.5 cmH2O/l/s at 0.25 l/s, p < 0.05; from 9 +/- 2.4 to 3.8 +/- 0.8 cmH2O/l/s at 0.5 l/s; from 12.2 +/- 3.5 to 5.7 +/- 1.2 cmH2O/l/s at 0.75 l/s; from 16.9 +/- 6 to 9.3 +/- 3.8 cmH2O/l/s at 1 l/s, p < 0.01 respectively). Also the WOBett was significantly reduced after use of the OR (from 0.66 +/- 0.19 to 0.34 +/- 0.08 J/l; p < 0.05).

CONCLUSION

this experimental device can be safely and successfully used to remove obstructions from the ETT lumen, without suspending mechanical ventilation, reducing the need for rapid ETT substitution in emergency and life-threatening situations.

Evaluation of respiratory system resistance in mechanically ventilated patients: the role of the endotracheal tube

OBJECTIVE

To investigate the role played by the endotracheal tube (ETT) in the correct evaluation of respiratory system mechanics with the end inflation occlusion method during constant flow controlled mechanical ventilation.

SETTING

General ICU, university of Rome "La Sapienza".

PATIENTS

12 consecutive patients undergoing controlled mechanical ventilation.

METHODS

We compared the values of minimal resistance of the respiratory system (i.e. airway resistance) (RRS min) obtained: i) subtracting the theoretical value of ETT resistance from the difference between P max and P1, measured on airway pressure tracings obtained from the distal end of the ETT; ii) directly measuring airway pressure 2 cm below the ETT, thus automatically excluding ETT resistance from the data. RESULTS. The values of RRS min obtained by measuring airway pressure below the ETT were significantly lower than those obtained by measuring airway pressure at the distal end of the ETT and subtracting the theoretical ETT resistance (4.5 +/- 2.8 versus 2.5 +/- 1.6 cm H2O/l/s, p < 0.01).

CONCLUSION

When precise measurements of ohmic resistances are required in mechanically ventilated patients, the measurements must be obtained from airways pressure data obtained at tracheal level. The "in vivo" positioning of ETT significantly increases the airflow resistance of the ETT.