An algorithm for the sedation of patients with obstructive sleep apnea by non-anesthesiologists.

OBJECTIVE: Patients with obstructive sleep apnea (OSA) are at risk for adverse events when moderate sedation is administered by nurse protocols (NAMS) under the guidance of non-anesthesiologists. An algorithm was applied for the appropriate section of patients to receive NAMS and the application of continuous positive airway pressure (CPAP). METHODS: An algorithm was developed for patients with OSA who were scheduled for gastroenterology, radiology, and cardiology procedures using NAMS. Those with normal airways and without contraindications for NAMS were classified as CPAP-independent (CPAP-I; not routinely used) or CPAP-dependent (CPAP-D; always used). CPAP machines were brought in by CPAP-D patients or supplied by the hospital and set at a patient's routine setting or 10 cm H2O if not known. CPAP-D patients for procedures for which CPAP could not be applied were done under anesthesia care. We retrospectively examined this program for the 2008-2018 period. RESULTS: Since the inception of this protocol in 2008, 803 patients with OSA safely underwent procedures using either personal CPAP or CPAP provided by the hospital. CONCLUSIONS: Patients with OSA can safely have NAMS for procedures when CPAP is applied based on a protocol that considers airway evaluation, the procedure, and whether there is dependence upon CPAP.

Respiratory Physiology for the Anesthesiologist.

Respiratory function is fundamental in the practice of anesthesia. Knowledge of basic physiologic principles of respiration assists in the proper implementation of daily actions of induction and maintenance of general anesthesia, delivery of mechanical ventilation, discontinuation of mechanical and pharmacologic support, and return to the preoperative state. The current work provides a review of classic physiology and emphasizes features important to the anesthesiologist. The material is divided in two main sections, gas exchange and respiratory mechanics; each section presents the physiology as the basis of abnormal states. We review the path of oxygen from air to the artery and of carbon dioxide the opposite way, and we have the causes of hypoxemia and of hypercarbia based on these very footpaths. We present the actions of pressure, flow, and volume as the normal determinants of ventilation, and we review the resulting abnormalities in terms of changes of resistance and compliance.

The physiologic basis for goal-directed hemodynamic and fluid therapy: the pivotal role of the venous circulation.

PURPOSE: Understanding cardiovascular physiology should help clinicians to understand the purpose of fluid and drug management during the perioperative period. The purpose of this narrative review is to describe the pivotal role of the venous circulation in goal-directed hemodynamic and fluid therapy. SOURCE: We selected relevant literature that examines the appropriateness of fluid therapy and pharmacologic interventions during the perioperative period. PRINCIPAL FINDINGS: The interaction between the stressed and unstressed intravascular volume (Vs and Vu, respectively) regulates the venous return, which is the main determinant of cardiac output. The lack of hemodynamic response to an intravascular fluid challenge likely results from an unpredictable distribution of infused fluid between the Vs and Vu. Other factors affecting hemodynamic responses include the pharmacodynamics of common vasoactive drugs, which further highlight the complexity of the regulation of venous return during infusion of exogenous catecholamines. The response to even a highly selective agent can result in different hemodynamic effects. Low doses of α-adrenergic agonists constrict veins and may often shift blood from the Vu to the Vs, subsequently increasing the venous return and cardiac output, whereas higher drug doses constrict arteries and usually decrease cardiac output. CONCLUSIONS: The physiologic basis of goal-directed hemodynamic therapy is complex and not necessarily reflected in the information received from hemodynamic monitors. Understanding the physiologic basis of such therapy is a logical step towards its optimal use.

Benefit of using a "bundled" consent for intensive care unit procedures as part of an early family meeting.

PURPOSE: Relatives of patients in the intensive care unit (ICU) are often dissatisfied with family-physician communication. Our prospective preintervention and postintervention study tested the hypothesis that introducing this informed consent process would improve family satisfaction with the ICU process of care. MATERIALS AND METHODS: We developed a consent form that included an introductory explanation of the main ICU interventions and a description of 8 common procedures in a surgical ICU. We administered it early in the ICU course during a scheduled family meeting. The study was a prospective preintervention and postintervention design. RESULTS: The "Family Satisfaction in the Intensive Care Unit" (FS-ICU) score was higher in the intervention than in the control group (95.4±4 vs 78.2±22, P<.001). The nursing perception of satisfaction with care was also higher in the intervention group (95.8±13 vs 71.9±28, P<.001). CONCLUSION: A bundled informed consent resulted in higher family satisfaction with the process of care in ICU.

Effects of routine monitoring of delirium in a surgical/trauma intensive care unit.

BACKGROUND: Delirium is prevalent in surgical and trauma intensive care units (ICUs) and carries substantial morbidity. This study tested the hypothesis that daily administration of a diagnostic instrument for delirium in a surgical/trauma ICU decreases the time of institution of pharmacologic therapy and improves related outcomes. METHODS: Controlled trial of two concurrent groups. The Confusion-Assessment Method for ICU was administered daily to all eligible patients admitted to our surgical/trauma ICU for 48 hours or longer. The result was communicated to one of the two preexisting ICU services (intervention service) and not the other (control service). Primary outcome was the time between diagnosis of delirium and pharmacologic treatment. Secondary outcomes included duration of delirium, mechanical ventilation, and ICU stay. RESULTS: Delirium occurred in 98 (35%) of 283 consecutive patients. Time between diagnosis and therapy did not differ between intervention (35 [35] hours) and control (40 [41] hours) groups. There was a difference in the number of delirium days treated in the intervention (73%) versus control (64%) groups (p = 0.035). The intervention group had significantly lower odds to neglect treating delirium when delirium was present (odds ratio, 0.67; 95% confidence interval, 0.45-1.00; p = 0.05). In the subgroup of trauma patients, the odds ratio of negligence was 0.37 (95% confidence interval, 0.14-0.99; p = 0.048), indicating lower probability for trauma patients to be untreated. There was no difference in the average duration of delirium, mechanical ventilation, and ICU stay. CONCLUSION: In our surgical/trauma ICU, daily screening for delirium did not affect the timing of pharmacologic therapy. Although the intervention resulted in a higher number of delirious ICU patients being treated, particularly trauma patients, there was no effect on related outcomes. LEVEL OF EVIDENCE: Therapeutic study, level IV.

The clinical significance of delirium in the intensive care unit.

Delirium is prevalent among intensive care unit patients. It prolongs length of stay, increases costs, and is independently associated with higher mortality rates. While its specific biological pathways are largely unknown, environmental and iatrogenic determinants have been repeatedly recognized. Removal of the known triggers and pharmacologic intervention constitute available therapies. This review focuses on the clinical significance of delirium in critically ill patients, from its prevalence to its long-term impact, the ways that we have to diagnose it, and the available therapeutic options.

Clinical and economic burden of postoperative pulmonary complications: patient safety summit on definition, risk-reducing interventions, and preventive strategies.

OBJECTIVE: Postoperative pulmonary complications are a major contributor to the overall risk of surgery. We convened a patient safety summit to discuss ways to enhance physician awareness of postoperative pulmonary complications, advance postoperative pulmonary complications as a substantive public health concern demanding national attention, recommend strategies to reduce the deleterious impact of postoperative pulmonary complications on clinical outcomes and healthcare costs, and establish an algorithm that will help identify patients who are at increased risk for postoperative pulmonary complications. DATA SOURCES: We conducted PubMed searches for relevant literature on postoperative pulmonary complications in addition to using the summit participants' experience in the management of patients with postoperative pulmonary complications. DATA SYNTHESIS: Postoperative pulmonary complications are common, are associated with increased morbidity and mortality, and adversely affect financial outcomes in health care. A multifaceted approach is necessary to reduce the incidence of postoperative pulmonary complications. Identifying a measurable marker of risk will facilitate the targeted implementation of risk-reduction strategies. CONCLUSIONS: The most practicable marker that identifies patients at highest risk for postoperative pulmonary complications is the need for postoperative mechanical ventilation of a cumulative duration >48 hrs.

Modifying endotracheal tubes to prevent ventilator-associated pneumonia.

PURPOSE OF REVIEW: The endotracheal tube (ETT) is the main avenue leading to airway contamination and subsequent ventilator-associated pneumonia (VAP) during mechanical ventilation. A number of modifications to the ETT are available, aimed at reducing the incidence of VAP. We review here available systems and devices, and clinical data regarding their efficacy. RECENT FINDINGS: Three main modifications of ETTs have been developed: coating with antimicrobials, adding a suction channel for the removal of oro-pharyngeal secretions, and modifying the design of the cuff. Each of these interventions has been shown to limit bacterial colonization of the distal airways and to decrease the incidence of VAP. Data on their ultimate effect on related clinical outcomes are still lacking. SUMMARY: Modifications of ETTs aimed at decreasing the onset of VAP show promising results. However, the lack of a significant effect on outcomes prompts us to use caution before recommending their widespread use.

Do Patients with Obstructive Sleep Apnea have an Increased Risk of Desaturation During Induction of Anesthesia for Weight Loss Surgery?

BACKGROUND: Obstructive sleep apnea (OSA) is an independent risk factor to develop perioperative complications during weight loss surgery, but the mechanisms are unclear. It is possible, that patients with OSA have a higher incidence of desaturation during induction of anesthesia. METHODS: We enrolled 100 morbidly obese (body mass index: 53+/-10) adult patients undergoing open bariatric surgery in a prospective study. At least 1 h before induction of anesthesia, peripheral oxygen saturation (SpO(2)) was measured by an oximetry finger probe in the sitting and supine positions, and Mallampati score was taken. Oxygen saturation was recorded also during induction of anesthesia, and nadir values were analyzed, and the STOP-BANG questionnaire was applied. RESULTS: Thirty-six patients presented with clinical suspicion of OSA. Body weight predicted oxygen saturation in the supine and sitting position, prior to induction of anesthesia. Nadir oxygen saturation during induction of anesthesia was considerably higher in patients with clinical suspicion of OSA, a significant finding that persisted as a trend after correction for age, gender and BMI. The Mallampati score was an independent predictor of OSA, even in morbidly obese patients scheduled for weight loss surgery. CONCLUSIONS: Morbidly obese patients presenting for weight loss surgery have a significant risk to desaturate during induction of anesthesia. A history of OSA does not independently increase the risk of desaturation during induction of anesthesia, if the appropriate precautions are being taken.

Bradycardia leading to asystole during dexmedetomidine infusion in an 18 year-old double-lung transplant recipient.

The case of an 18 year-old double-lung transplant recipient recovering from acute respiratory distress syndrome who developed repeated episodes of bradycardia and asystole (maximum duration: 10 sec) during dexmedetomidine administration is presented. Increased baseline vagal tone, paroxysmal coughing spells, and opioid administration were likely contributors to the episodes. Discontinuation of the drug restored regular sinus rhythm. Double-lung transplant recipients may be at especially increased risk for this phenomenon as a result of changes in the autonomic innervation of the heart.

Lateral-horizontal patient position and horizontal orientation of the endotracheal tube to prevent aspiration in adult surgical intensive care unit patients: a feasibility study.

BACKGROUND: Recent data suggest that during mechanical ventilation the lateral-horizontal patient position (in which the endotracheal tube is horizontal) decreases the risk of ventilator-associated pneumonia, compared to the recommended semi-recumbent position (in which the endotracheal tube slopes downward into the trachea). We tested the feasibility of the lateral-horizontal patient position, measured the incidence of aspiration of gastric contents, and watched for any adverse effects related to the lateral-horizontal position. METHODS: Ten adult intensive care unit patients were ventilated for 64 hours in the standard semi-recumbent position, and ten for 12-24 hours in the lateral-horizontal position. Tracheal secretions were collected every 8 hours and every 4 hours, respectively, and tested for pepsin, which is a marker of gastric contents. We also recorded clinical, physiologic, and outcome variables. RESULTS: The patients remained stable during ventilation in the lateral-horizontal position, and no adverse events occurred. Pepsin was detected in the trachea of 7 semi-recumbent patients and in five of the lateral-horizontal patients (P = .32). The number of ventilator-free days was 8 days (range 0-21 days) in the semi-recumbent patients, versus 24 days (range 12-25 days) in the lateral-horizontal patients (P = .04). CONCLUSIONS: Implementing the lateral-horizontal position for 12-24 hours in adult intubated intensive care unit patients is feasible, and our patients had no adverse events. The incidence of aspiration of gastric contents in the lateral-horizontal position seems to be similar to that in the semi-recumbent position.

Comparison of conventional guaiac to four immunochemical methods for fecal occult blood testing: implications for clinical practice in hospital and outpatient settings.

BACKGROUND: Fecal occult blood testing (FOBT) is one method to screen for colorectal cancer and to assess for gastrointestinal bleeding in hospitalized patients. Differences in the analytical sensitivity among various methods may have significant clinical repercussions. METHODS: We evaluated the analytical performance of 5 different FOBT methods (standard guaiac-based method and four immunochemical methods) using patient samples and spiked stool specimens. RESULTS: The analytical sensitivity measured using spiked stool samples varied from <8 to 1500 ug hemoglobin/gram of stool. In some cases the results differed significantly from the manufacturers reported analytical sensitivity. Analysis of 71 stool samples measured by all 5 methods showed a discrepant result in 31 cases (43.7%). The rate of positive samples varied by method from 8.5% to 42.2%. CONCLUSIONS: These results demonstrate significant differences in the analytical performance among FOBT methods. Careful method validation and selection of a method with appropriate sensitivity is essential when choosing an FOBT method for colorectal cancer screening or for the assessment of gastrointestinal bleeding in the emergency department and hospital inpatients.

Effect of laboratory testing guidelines on the utilization of tests and order entries in a surgical intensive care unit.

OBJECTIVE: Diagnostic testing is frequently overused in the intensive care unit. We devised guidelines to optimize blood tests utilization, and designed this study to quantify their efficacy over time, their safety, and their possible benefits. DESIGN: Laboratory testing guidelines were created by consensus and implemented through repeated staff education. The guidelines included: a) the tests to be obtained daily: complete blood count, serum electrolytes, urea nitrogen, creatinine, and blood glucose concentration; b) the need to discuss laboratory testing at daily patient's rounds; c) the need to provide a written order for all tests. The number of tests performed, corresponding physician orders, and various outcome measures were collected for two 6-month study periods, before and after the first day of implementation of the guidelines. SETTING: Twenty-bed surgical intensive care unit in a tertiary care teaching hospital. PATIENTS: All patients admitted during the two study periods. METHODS: Laboratory tests and related physician orders, demographics, blood products transfusion, and outcomes were collected from hospital databases. In prospectively defined subgroups, additional outcome measures were obtained by ad-hoc chart review. RESULTS: One thousand one hundred seventeen patients were enrolled. After the institution of the guidelines, the number of laboratory tests decreased by 37% (from 64,305 to 40,877), and the number of respective physician orders increased by 38% (from 20,940 to 35,472), p < 0.001. These results were manifest within 1 month, sustained through the study period, and still present at 1 yr. No changes in outcomes or in the rates of selected complications were detected. Red blood cells utilization correlated linearly (r .47) with the number of blood tests performed in both study periods. CONCLUSIONS: Guidelines designed to optimize laboratory tests use in an intensive care unit can produce rapid and long-lasting effects, can be safe, and may affect the number of red blood cell units transfused.

Internally coated endotracheal tubes with silver sulfadiazine in polyurethane to prevent bacterial colonization: a clinical trial.

OBJECTIVE: Coated medical devices have been shown to reduce catheter-related infections. We coated endotracheal tubes (ETT) with silver sulfadiazine (SSD), and tested them in a clinical study to assess the feasibility, safety, and efficacy of preventing bacterial colonization. DESIGN: A prospective, randomized clinical trial, phase I-II. SETTING: Academic intensive care unit (ICU). PARTICIPANTS: Forty-six adult patients expected to need 12-24 h of intubation were randomized into two groups. INTERVENTIONS: Patients were randomized to be intubated with a standard non-coated ETT (St-ETT, n=23; control group), or with a SSD-coated ETT (SSD-ETT, n=23). MEASUREMENTS AND RESULTS: Coating with SSD prevented bacterial colonization of the ETT (frequency of colonization: SSD-ETT 0/23, St-ETT 8/23; p<0.01). No organized bacterial biofilm could be identified on the lumen of any ETT; however, SSD was associated with a thinner mucus layer (in the SSD-ETT secretion deposits ranged from 0 to 200 microm; in the St-ETT deposits ranged between 50 and 700 microm). No difference was observed between the two groups in the tracheobronchial brush samples (frequency of colonization: SSD-ETT 0/23, St-ETT 2/23; p=0.48). No adverse reactions were observed with the implementation of the novel device. CONCLUSION: SSD-ETT can be safely used in preventing bacterial colonization and narrowing of the ETT in patients intubated for up to 24 h (mean intubation time 16 h).