Carlos Romero

Effects of Prone Positioning on Lung Protection in Patients with Acute Respiratory Distress Syndrome

RATIONALE Positive end-expiratory pressure (PEEP) and prone positioning may induce lung recruitment and affect alveolar dynamics in acute respiratory distress syndrome (ARDS). Whether there is interdependence between the effects of PEEP and prone positioning on these variables is unknown. OBJECTIVES To determine the effects of high PEEP and prone positioning on lung recruitment, cyclic recruitment/derecruitment, and tidal hyperinflation and how these effects are influenced by lung recruitability. METHODS Mechanically ventilated patients (Vt 6 ml/kg ideal body weight) underwent whole-lung computed tomography (CT) during breath-holding sessions at airway pressures of 5, 15, and 45 cm H2O and Cine-CTs on a fixed thoracic transverse slice at PEEP 5 and 15 cm H2O. CT images were repeated in supine and prone positioning. A recruitment maneuver at 45 cm H2O was performed before each PEEP change. Lung recruitability was defined as the difference in percentage of nonaerated tissue between 5 and 45 cm H2O. Cyclic recruitment/de-recruitment and tidal hyperinflation were determined as tidal changes in percentage of nonaerated and hyperinflated tissue, respectively. MEASUREMENTS AND MAIN RESULTS Twenty-four patients with ARDS were included. Increasing PEEP from 5 to 15 cm H2O decreased nonaerated tissue (501 ± 201 to 322 ± 132 grams; P < 0.001) and increased tidal-hyperinflation (0.41 ± 0.26 to 0.57 ± 0.30%; P = 0.004) in supine. Prone positioning further decreased nonaerated tissue (322 ± 132 to 290 ± 141 grams; P = 0.028) and reduced tidal hyperinflation observed at PEEP 15 in supine patients (0.57 ± 0.30 to 0.41 ± 0.22%). Cyclic recruitment/de-recruitment only decreased when high PEEP and prone positioning were applied together (4.1 ± 1.9 to 2.9 ± 0.9%; P = 0.003), particularly in patients with high lung recruitability. CONCLUSIONS Prone positioning enhances lung recruitment and decreases alveolar instability and hyperinflation observed at high PEEP in patients with ARDS.

Swallowing dysfunction in nonneurologic critically ill patients who require percutaneous dilatational tracheostomy.

BACKGROUND The aim of this study was to determine the incidence of swallowing dysfunction in nonneurologic critically ill patients who require percutaneous dilatational tracheostomy (PDT) for prolonged mechanical ventilation (MV) and to compare the duration of the cannulation period and length of stay in the critical care unit (CCU) in patients with and without swallowing dysfunction. METHODS A total of 40 consecutive patients without neurologic disorders who require PDT for prolonged MV were included. Previous to the tracheostomy decannulation process, an otolaryngologist performed a fiberoptic endoscopic evaluation of swallowing (FEES). We used analysis of variance for the analysis; the results are presented as mean values +/- SD. RESULTS Mean age was 62 +/- 15 years. Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores were 21 +/- 2 and 9 +/- 1, respectively. Time of MV previous to PDT was 20 +/- 11 days, total MV duration was 38 +/- 16 days, and CCU stay was 63 +/- 27 days. The incidence of swallowing dysfunction in this group of patients was 38% (15/40). No difference was found in the age or time period of MV previous to PDT between groups. The time period between FEES to tracheostomy decannulation process was 19 +/- 11 days in patients with swallowing dysfunction vs 2 +/- 4 days in those patients without dysfunction (P < .001). Patients who developed swallowing dysfunction stayed longer in the CCU (69 +/- 23 vs 47 +/- 19 days, P < .01). CONCLUSIONS Nearly 40% of nonneurologic critically ill patients requiring PDT for prolonged MV presented swallowing dysfunction and experienced a significant delay in their tracheostomy decannulation process.

Higher than recommended amikacin loading doses achieve pharmacokinetic targets without associated toxicity

Antibiotic therapy improves the outcome of severe sepsis and septic shock, however pharmacokinetic properties are altered in this scenario. Amikacin (AMK) is an option to treat community or nosocomial infections, although standard doses might be insufficient in critically ill patients. The aim of this study was to evaluate two AMK dosage regimens in comparison with standard therapy with regard to efficacy in achieving adequate plasma levels as well as safety. In total, 99 patients with severe sepsis or septic shock were randomised to different AMK dose protocols: Group 1, 25 mg/kg/day; Group 2, 30 mg/kg/day; and Group 3, historical standard dose (15 mg/kg/day). Peak plasma concentrations at 1 h (C(max)) were determined. Pharmacokinetics was determined and renal function was monitored to evaluate toxicity. Groups were compared using bilateral T-test. Demographic characteristics of the three groups were comparable. AMK C(max) values were 57.4±9.8, 72.1±18.4 and 35.2±9.4 μg/mL, respectively (P<0.001 between Groups 1 and 2 versus Group 3, and P<0.01 between Group 1 versus Group 2). A C(max)>60 μg/mL was reached by 39%, 76% and 0% of patients in Groups 1, 2 and 3, respectively (P<0.001) and creatinine clearance at Day 28 was 95.6±47.4, 89.7±26.6 and 56.4±18.4 mL/min, respectively. In conclusion, a 30 mg/kg daily dose of AMK presents significantly higher C(max) compared with the other groups, with 76% of patients reaching recommended peak plasma levels with no association with higher nephrotoxicity. Standard doses are insufficient in critically ill patients to reach the recommended C(max).

When to stop septic shock resuscitation: clues from a dynamic perfusion monitoring

BackgroundThe decision of when to stop septic shock resuscitation is a critical but yet a relatively unexplored aspect of care. This is especially relevant since the risks of over-resuscitation with fluid overload or inotropes have been highlighted in recent years. A recent guideline has proposed normalization of central venous oxygen saturation and/or lactate as therapeutic end-points, assuming that these variables are equivalent or interchangeable. However, since the physiological determinants of both are totally different, it is legitimate to challenge the rationale of this proposal. We designed this study to gain more insights into the most appropriate resuscitation goal from a dynamic point of view. Our objective was to compare the normalization rates of these and other potential perfusion-related targets in a cohort of septic shock survivors.MethodsWe designed a prospective, observational clinical study. One hundred and four septic shock patients with hyperlactatemia were included and followed until hospital discharge. The 84 hospital-survivors were kept for final analysis. A multimodal perfusion assessment was performed at baseline, 2, 6, and 24 h of ICU treatment.ResultsSome variables such as central venous oxygen saturation, central venous-arterial pCO2 gradient, and capillary refill time were already normal in more than 70% of survivors at 6 h. Lactate presented a much slower normalization rate decreasing significantly at 6 h compared to that of baseline (4.0 [3.0 to 4.9] vs. 2.7 [2.2 to 3.9] mmol/L; p < 0.01) but with only 52% of patients achieving normality at 24 h. Sublingual microcirculatory variables exhibited the slowest recovery rate with persistent derangements still present in almost 80% of patients at 24 h.ConclusionsPerfusion-related variables exhibit very different normalization rates in septic shock survivors, most of them exhibiting a biphasic response with an initial rapid improvement, followed by a much slower trend thereafter. This fact should be taken into account to determine the most appropriate criteria to stop resuscitation opportunely and avoid the risk of over-resuscitation.

Fiberoptic bronchoscopy–assisted percutaneous tracheostomy is safe in obese critically ill patients: A prospective and comparative study

BACKGROUND Obesity has reached epidemic proportions worldwide. In Latin America, 10% to 35% of the population is obese. Obese critically ill patients are at greater risk for requiring intubation and prolonged mechanical ventilation; and in some cases, it is necessary to perform a tracheostomy. OBJECTIVE The objective of the study was to compare the incidence of perioperative complications associated with percutaneous tracheostomy (PT) using the fiberoptic bronchoscopy-assisted Ciaglia Blue Rhino technique (Cook Critical Care, Bloomington, IN) in obese vs nonobese critically ill patients. PATIENTS AND METHOD A prospective evaluation was made of 120 patients who underwent PT because of prolonged mechanical ventilation. An analysis of the incidence of operative and early postoperative complications was performed comparing an obese patient group (n = 25) with a nonobese patient group (n = 80). Obesity was defined by a body mass index of at least 30 kg/m(2). RESULTS The 2 groups had no significant differences in their demographic characteristics. The average body mass index for the obese patient group was 38 +/- 9 kg/m(2) vs 22 +/- 3 kg/m(2) for the nonobese patient group (P < .001). The obese patients required 18 +/- 7 days of mechanical ventilation, on average, before PT vs 16 +/- 7 days for the nonobese patients (P = .15). The incidence of operative complications for the obese patients vs nonobese patients was 8% and 7.5%, respectively (P = 1). The incidence of early postoperative complications was 8% for the obese patients vs 2.5% for the nonobese patients (P = .2). CONCLUSION Percutaneous tracheostomy using the fiberoptic bronchoscopy-assisted Ciaglia Blue Rhino technique is safe for obese critically ill patients when performed by an experienced intensivist.

Evolution of peripheral vs metabolic perfusion parameters during septic shock resuscitation. A clinical-physiologic study

PURPOSE Perfusion assessment during septic shock resuscitation is difficult and usually complex determinations. Capillary refill time (CRT) and central-to-toe temperature difference (Tc-toe) have been proposed as objective reproducible parameters to evaluate peripheral perfusion. The comparative evolution of peripheral vs metabolic perfusion parameters in septic shock resuscitation has not been studied. We conducted a prospective observational clinical-physiologic study to address this subject. METHODS Patients with sepsis-related circulatory dysfunction were resuscitated according to a standard local algorithm. Perfusion assessment included serial determinations of metabolic (central venous O(2) saturation [Scvo(2)] and central venous to arterial Pco(2) gradient [P(cv-a)co(2)]) and peripheral perfusion parameters (CRT and Tc-toe, among others). Successful resuscitation was defined as a normal plasma lactate at 24 hours. RESULTS Forty-one patients were included. The presence of normal values for both CRT and Tc-toe considered together at 6 hours was independently associated with a successful resuscitation (P = .02), as compared with the behavior of metabolic parameters. Capillary refill time was the first parameter to be significantly normalized. CONCLUSION Early recovery of peripheral perfusion anticipates a successful resuscitation compared with traditional metabolic parameters in septic shock patients. Our findings support the inclusion of serial peripheral perfusion assessment in multimodal monitoring strategies for septic shock resuscitation.

Extended prone position ventilation in severe acute respiratory distress syndrome: A pilot feasibility study

OBJECTIVES The aim of the study was to evaluate the safety of extended prone position ventilation (PPV) and its impact on respiratory function in patients with severe acute respiratory distress syndrome (ARDS). DESIGN This was a prospective interventional study. SETTING Patients were recruited from a mixed medical-surgical intensive care unit in a university hospital. PATIENTS Fifteen consecutive patients with severe ARDS, previously unresponsive to positive end-expiratory pressure adjustment, were treated with PPV. INTERVENTION Prone position ventilation for 48 hours or until the oxygenation index was 10 or less (extended PPV). RESULTS The elapsed time from the initiation of mechanical ventilation to pronation was 35 +/- 11 hours. Prone position ventilation was continuously maintained for 55 +/- 7 hours. Two patients developed grade II pressure ulcers of small extent. None of the patients experienced life-threatening complications or hemodynamic instability during the procedure. The patients showed a statistically significant improvement in Pao(2)/Fio(2) (92 +/- 12 vs 227 +/- 43, P < .0001) and oxygenation index (22 +/- 5 vs 8 +/- 2, P < .0001), reduction of PaCo(2) (54 +/- 9 vs 39 +/- 4, P < .0001) and plateau pressure (32 +/- 2 vs 27 +/- 3, P < .0001), and increment of the static compliance (21 +/- 3 vs 37 +/- 6, P < .0001) with extended PPV. All the parameters continued to improve significantly while they remained in prone position and did not change upon returning the patients to the supine position. CONCLUSIONS The results obtained suggest that extended PPV is safe and effective in patients with severe ARDS when it is carried out by a trained staff and within an established protocol. Extended PPV is emerging as an effective therapy in the rescue of patients from severe ARDS.

Effects of the implementation of a preventive interventions program on the reduction of medication errors in critically ill adult patients.

PURPOSE Medication errors (MEs) are a major factor limiting the effectiveness and safety of pharmacological therapies in critically ill patients. The purpose was to determine if a preventive interventions program (PIP) is associated with a significant reduction on prevalence of patients with MEs in intensive care unit (ICU). METHODS A prospective before-after study was conducted in a random sample of adult patients in a medical-surgical ICU. Between 2 observational phases, a PIP (bundle of interventions to reduce MEs) was implemented by a multidisciplinary team. Direct observation was used to detect MEs at baseline and postintervention. Each medication process, that is, prescription, transcription, dispensing, preparation, and administration, was compared with what the prescriber ordered; if there was a difference, the error was described and categorized. Medication errors were defined according to the National Coordinating Council for Medication Error Reporting and Prevention. RESULTS A total of 410 medications for 278 patients were evaluated. A 31.7% decrease on the prevalence of patients with MEs (41.9%-28.6%; P < .05) was seen. Main variations occurred in anti-infectives for systemic use and prescription and administration stage. CONCLUSIONS The implementation of PIP by a multidisciplinary team resulted in a significant reduction on the prevalence of patients with ME at an adult ICU.

Successful response to intravenous immunoglobulin as rescue therapy in a patient with Hashimoto's encephalopathy

The authors describe the case of a 61-year-old woman who was admitted to our intensive care unit (ICU) due to impaired consciousness associated with generalised seizures. Her cerebrospinal fluid, electrolytes, acid-base analysis, and common laboratory and toxicology tests were normal. An MRI ruled out the presence of stroke or haemorrhage but showed severe leukoencephalopathy. Parkinsons disease, Creuzfeld–Jacob disease, vascular alterations, cancer, and rheumatological and metabolic diseases were evaluated and excluded. In view of her history of hypothyroidism despite adequate hormonal replacement and clinical behaviour, Hashimotos encephalopathy was considered. Anti-thyroperoxidase levels were above 3000 IU/ml. The patient received 5 g of methylprednisolone followed by prednisone, but after a favourable initial response, returned to a comatose state. However, after administration of intravenous immunoglobulin (IVIG) 2 g/kg, the patient recovered with resolution of neurological symptoms and was discharged from the ICU 4 days after finishing IVIG treatment.

Errores de medicación en pacientes críticos adultos de un hospital universitario: Estudio prospectivo y aleatorio

BACKGROUND Critically ill patients are especially vulnerable to medication errors (ME) due to their severe clinical situation and the complexities of their management. AIM To determine the frequency and characteristics of ME and identify shortcomings in the processes of medication management in an Intensive Care Unit. PATIENTS AND METHODS During a 3 months period, an observational prospective and randomized study was carried out in the ICU of a university hospital. Every step of patients medication management (prescription, transcription, dispensation, preparation and administration) was evaluated by an external trained professional. Steps with higher frequency of ME and their therapeutic groups involved were identified. Medications errors were classified according to the National Coordinating Council for Medication Error Reporting and Prevention. RESULTS In 52 of 124 patients evaluated, 66 ME were found in 194 drugs prescribed. In 34% of prescribed drugs, there was at least 1 ME during its use. Half of ME occurred during medication administration, mainly due to problems in infusion rates and schedule times. Antibacterial drugs had the highest rate of ME. CONCLUSIONS We found a 34% rate of ME per drug prescribed, which is in concordance with international reports. The identification of those steps more prone to ME in the ICU, will allow the implementation of an intervention program to improve the quality and security of medication management.