Differential Effect of Targeted Temperature Management Between 32 °C and 36 °C Following Cardiac Arrest According to Initial Severity of Illness: Insights From Two International Data Sets

BACKGROUND

Recent guidelines have emphasized actively avoiding fever to improve outcomes in patients who are comatose following resuscitation from cardiac arrest (ie, out-of-hospital cardiac arrest). However, whether targeted temperature management between 32 °C and 36 °C (TTM32-36) can improve neurologic outcome in some patients remains debated.

RESEARCH QUESTION

Is there an association between the use of TTM32-36 and outcome according to severity assessed at ICU admission using a previously derived risk score?

STUDY DESIGN AND METHODS

Data prospectively collected in the Sudden Death Expertise Center (SDEC) registry (France) between May 2011 and December 2017 and in the Resuscitation Outcomes Consortium Continuous Chest Compressions (ROC-CCC) trial (United States and Canada) between June 2011 and May 2015 were used for this study. Severity at ICU admission was assessed through a modified version of the Cardiac Arrest Hospital Prognosis (mCAHP) score, divided into tertiles of severity. The study explored associations between TTM32-36 and favorable neurologic status at hospital discharge by using multiple logistic regression as well as in tertiles of severity for each data set.

RESULTS

A total of 2,723 patients were analyzed in the SDEC data set and 4,202 patients in the ROC-CCC data set. A favorable neurologic status at hospital discharge occurred in 728 (27%) patients in the French data set and in 1,239 (29%) patients in the North American data set. Among the French data set, TTM32-36 was independently associated with better neurologic outcome in the tertile of patients with low (adjusted OR, 1.63; 95% CI, 1.15-2.30; P = .006) and high (adjusted OR, 1.94; 95% CI, 1.06-3.54; P = .030) severity according to mCAHP at ICU admission. Similar results were observed in the North American data set (adjusted ORs of 1.36 [95% CI, 1.05-1.75; P = .020] and 2.42 [95% CI, 1.38-4.24; P = .002], respectively). No association was observed between TTM32-36 and outcome in the moderate groups of the two data sets.

INTERPRETATION

TTM32-36 was significantly associated with a better outcome in patients with low and high severity at ICU admission assessed according to the mCAHP score. Further studies are needed to evaluate individualized temperature control following out-of-hospital cardiac arrest.

Prehabilitation in hepato-pancreato-biliary surgery: A systematic review and meta-analysis. A necessary step forward evidence-based sample size calculation for future trials

INTRODUCTION

Prehabilitation is defined as preoperative conditioning of patients in order to improve post-operative outcomes. Some studies showed an increase in functional recovery following colorectal surgery, but its effect in hepato-pancreato-biliary (HPB) surgery is unclear. The aim of this study was to realize a systematic literature review and meta-analysis on the current available evidence on prehabilitation in HPB surgery.

MATERIALS AND METHODS

A systematic review and a metanalysis were carried out on prehabilitation (physical, nutritional and psychological interventions) in HPB surgery (2009-2019). Assessed outcomes were postoperative complications, length of stay (LOS), 30-day readmission, and mortality.

MAIN RESULTS

Four studies among the 191 screened were included in this systematic review (3 randomized controlled trials, 1 case-control propensity score study), involving 419 patients (prehabilitation group, n=139; control group, n=280). After pooling, no difference was observed on LOS ((-4.37 days [95% CI: -8.86; 0.13]) or postoperative complications (RR 0.83 [95%CI: 0.62; 1.10]), reported by all the included studies. Two trials reported on readmission rate, but given the high heterogeneity, a meta-analysis was not realized. No deaths were reported among the included studies.

CONCLUSION

No effect of prehabilitation programs in HPB surgery was observed on LOS or postoperative complications rate. Future trials with standardized outcomes of measure, and adequately powered samples calculations are thus required.

PROSPERO REGISTRATION

CRD42020165218.

Retour d’expérience sur la direction médicale de crise à l’Assistance publique–Hôpitaux de Paris pendant la crise Covid-19

Un retour d’expérience sur la direction médicale de crise (DMC) pendant la première phase de l’épidémie de Covid-19 a été effectué à l’Assistance publique–Hôpitaux de Paris (AP–HP), le plus important centre hospitalier universitaire européen. L’AP–HP s’est dotée d’un directeur médical de crise (DMC) AP–HP, de six DMC de groupes hospitaliers (GH) et d’un DMC pour chacun des 39 sites hospitaliers. Le pilotage s’est appuyé sur des réunions quotidiennes de crise AP–HP et de GH, des groupes de travail disciplinaires et des tableaux de bord quotidiens fiabilisés qui ont permis d’optimiser les actions. Des actions innovantes ont été mises en place : cellules de régulation des entrées et des sorties de réanimation, suivi des patients infectés à domicile, traçage des contacts, transferts interrégionaux de patients de réanimation. Les éléments clés de la réussite ont été les relations entre direction générale et DMC, l’articulation entre l’échelon central (AP–HP) et celui des GH, la mobilisation de tous les acteurs vers un objectif unique identifié et la mobilisation de l’ensemble des soignants, y compris les étudiants. Parmi les pistes d’amélioration soulignées, il convient de citer la généralisation des DMC hors AP–HP, conformément à la réglementation, le développement de la connaissance du mode de fonctionnement de crise, l’anticipation de la formation à la gestion de crise, la réalisation d’une information quotidienne de l’ensemble des acteurs des actions menées dans une crise de longue durée et la participation des représentants des usagers. La gestion de la recherche en temps de crise reste à inventer au niveau national, voire européen.

Extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest: a registry study

Aims

Out-of-hospital cardiac arrest (OHCA) without return of spontaneous circulation (ROSC) despite conventional resuscitation is common and has poor outcomes. Adding extracorporeal membrane oxygenation (ECMO) to cardiopulmonary resuscitation (extracorporeal-CPR) is increasingly used in an attempt to improve outcomes.

Methods and results

We analysed a prospective registry of 13 191 OHCAs in the Paris region from May 2011 to January 2018. We compared survival at hospital discharge with and without extracorporeal-CPR and identified factors associated with survival in patients given extracorporeal-CPR. Survival was 8% in 525 patients given extracorporeal-CPR and 9% in 12 666 patients given conventional-CPR (P = 0.91). By adjusted multivariate analysis, extracorporeal-CPR was not associated with hospital survival [odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.8–2.1; P = 0.24]. By conditional logistic regression with matching on a propensity score (including age, sex, occurrence at home, bystander CPR, initial rhythm, collapse-to-CPR time, duration of resuscitation, and ROSC), similar results were found (OR, 0.8; 95% CI, 0.5–1.3; P = 0.41). In the extracorporeal-CPR group, factors associated with hospital survival were initial shockable rhythm (OR, 3.9; 95% CI, 1.5–10.3; P = 0.005), transient ROSC before ECMO (OR, 2.3; 95% CI, 1.1–4.7; P = 0.03), and prehospital ECMO implantation (OR, 2.9; 95% CI, 1.5–5.9; P = 0.002).

Conclusions

In a population-based registry, 4% of OHCAs were treated with extracorporeal-CPR, which was not associated with increased hospital survival. Early ECMO implantation may improve outcomes. The initial rhythm and ROSC may help select patients for extracorporeal-CPR.

Impact of graft preservation solutions for liver transplantation on early cytokine release and postoperative organ dysfunctions. A pilot study

INTRODUCTION

During liver transplantation, graft ischemia-reperfusion injury leads to a systemic inflammatory response producing postoperative organ dysfunctions. The aim of this observational and prospective study was to compare the impact of Solution de conservation des organes et tissus (SCOT) 15 and University of Wisconsin (UW) preservation solutions on early cytokine release, postreperfusion syndrome and postoperative organ dysfunctions.

METHODS

Thirty-seven liver transplantations were included: 21 in UW Group and 16 in SCOT 15 group. Five cytokines were measured in systemic blood after anesthetic induction, 30minutes after unclamping portal vein and on postoperative day 1.

RESULTS

Following unclamping portal vein, cytokines were released in systemic circulation. Systemic cytokine concentrations were higher in UW than in SCOT 15 group: Interleukin-10, Interleukine-6. In SCOT 15 group, significant reduction of postreperfusion syndrome incidence and acute kidney injury were observed. Alanine and aspartate aminotransferase peak concentrations were higher in SCOT 15 group than in UW group. However, from postoperative day 1 to day 10, aminotransferase returned to normal values and did not differ between groups.

CONCLUSIONS

Compared to UW, SCOT 15 decreases systemic cytokine release resulting from graft ischemia-reperfusion injury and reduces incidence of postreperfusion syndrome and postoperative renal failure.

Ultrasound assessment of lung consolidation and reaeration after pleural effusion drainage in patients with Acute Respiratory Distress Syndrome: a pilot study

PURPOSE

The aim of the pilot study was to assess by ultrasound changes in dimensions of lung consolidation and reaeration after drainage of large pleural effusion in patients with acute respiratory distress syndrome (ARDS).

METHODS

Lung ultrasound and blood gas were performed before, 2 hours (H2) and 24 hours (H24) after drainage of pleural effusion. Lung ultrasound aeration score was calculated. Cephalocaudal dimension and diaphragmatic transversal area of lung consolidation were measured.

RESULTS

Ten patients were studied. Median volume of drained effusion was 675 ml at H2 and 895 at H24. Two hours after drainage, dimension of cephalocaudal consolidation and diaphragmatic transversal area decreased significantly. Lung reaeration after drainage occurred mainly in latero-inferior and postero-superior regions. PaO2/FiO2 increased significantly at H24.

CONCLUSIONS

Ultrasound is a useful method to assess lung consolidation after pleural effusion drainage. Drainage of pleural effusion may lead to a decrease of lung consolidation and improvement of lung reaeration.

French survey of the first three-years of liver transplantation activity from uncontrolled donors deceased after cardiac death

OBJECTIVE

To assess the first three years of French activity related to liver transplantation from uncontrolled donation after cardiac death (uDCD).

STUDY DESIGN

Prospective and observational study in the three active centres authorized by the French Biomedicine Agency.

PATIENTS AND METHODS

All patients deceased between 2010 and 2012 after an uncontrolled cardiac arrest admitted to one of three centres (Pitié-Salpêtrière, Saint-Louis or Bicêtre hospitals, AP-HP, Paris, France) and potentially eligible for liver recovery were included. Abdominal normothermic oxygenated recirculation (ANOR) was used for graft preservation.

RESULTS

One hundred twenty-six potential uDCD donors were identified as eligible for liver recovery after hospital admission. The main causes of organ recovery failure were technical failure related to ANOR (29 patients, 23%), refusal of consent (39 patients, 31% of potential uDCD donors and 40% of asked relatives) and abnormal hepatic transaminases up to 200 UI.L(-1) during ANOR (24 patients, 19%). Finally, 11 livers were transplanted. Process efficiency was 9% [95% CI: 4-15%]. One-year recipient survival was 82%, [95% CI: 48-98%] and one-year graft survival was 64% [95% CI: 31-89%].

CONCLUSION

Liver transplantation from uDCD donors is achievable in France, despite low process efficiency.

Postoperative pulmonary complications updating

Postoperative pulmonary complications (PPCs) are a major contributor to the overall risk of surgery. PPCs affect the length of hospital stay and are associated with a higher in-hospital mortality. PPCs are even the leading cause of death either in cardiothoracic surgery but also in non-cardiothoracic surgery. Thus, reliable PPCs risk stratification tools are the key issue of clinical decision making in the perioperative period. When the risk is clearly identified related to the patient according the ARISCAT score and/or the type of surgery (mainly thoracic and abdominal), low-cost preemptive interventions improve outcomes and new strategies can be developed to prevent this risk. The EuSOS, PERISCOPE and IMPROVE studies demonstrated this care optimization by risk identification first, then risk stratification and new care (multifaceted) strategies implementation allowing a decrease in PPCs mortality by optimizing the clinical path of the patient and the care resources.

Airway management in obese patient

Oxygenation maintenance is the cornerstone of airway management in the obese patient related to anatomic and pathophysiologic issues. Difficult mask ventilation (DMV) risk is increased in obese patients according recognized predictors (Body Mass Index [BMI]>26 kg/m2, age >55 years, jaw protrusion severely limited, lack of teeth, snoring, beard, Mallampati class III or IV) and should systematically search. Difficult tracheal intubation (DTI) risk may be increased and risk should be assessed in a careful manner. Increased neck circumference and high BMI (>35 kg/m2) should be added to "standard" preoperative airway assessment including:Mallampati class, mouth opening and thyromental distance. In obese patients, preoxygenation is mandatory by 25° head-up position achieving better gas exchange than in supine position. In addition, to prevent early arterial oxygen desaturation related to a reduced functional residual capacity (FRC), atelectasis formation during anesthetic induction and after tracheal intubation, non invasive positive pressure ventilation and application of PEEP throughout this period are recommended. Airway management in obese patients has to consider: the anesthesia technique with maintenance or not of spontaneous ventilation, the available oxygenation technique in case of anticipated DMV, and the appropriate tracheal intubation technique (fiberoptic intubation technique or videolaryngoscope) according to the patient status and will. In unexpected difficult airway, the very first priority is oxygenation and a predefined strategy has to be implemented with oxygenation devices first (supraglottic devices or ILMA). Lastly, the final step of the obese airway management is tracheal extubation and recovery. A strategy with a fully awake patient, without residual paralysis, and a 25° head-up position is mandatory.

A year in review in Minerva Anestesiologica 2013

BACKGROUND

We organized a training program for oral fiber optic intubation (FOI) under conscious sedation. The efficacy of the program was evaluated by comparing the performances of experts and novices.

METHODS

The training procedure was divided into two sessions: a theoretical session on difficult airways, the fiber optic bronchoscope (FOB), remifentanil, topical anesthesia and patient interactions; and a session involving simulations of the FOI technique on dummies. For in vivo FOI, we enrolled patients requiring orotracheal intubation for elective surgery. Electrocardiograms, mean arterial pressure was railroaded over the fiberscope, and tracheal intubati6 and 7) FOIs, respectively, joined the study. To reach ±23 bpm, P=0.02), and RR was decreased (from 16±3 to 12±4 bpm, P<0.05). No differences were recorded between the experts and less-experienced anesthesiologists. The average duration of FOI was 3.3±2.0 min for experts and 4.2±2.4 min for novices (P=0.03). Procedures were successful in both groups, with patients in each group being equally satisfied with the procedures.

CONCLUSION

This study highlights the importance of a structured FOI training program, demonstrating that it is possible to learn to perform FOI proficiently by practicing on dummies.

[Malignant hyperthermia: multifactorial events leading to a crisis]

This case-report focused on the occurrence of a crisis of malignant hyperthermia on a young biker (21 y.o.) victim of a severe traffic accident. This observation gives some key points: the delayed occurrence of the crisis after 4 hours of surgery, the multi-factorial events that triggered the crisis; the choice to perform a quick diagnosis through gene analysis in comparison to the standard tests of caffeine on a muscular biopsy. These different points are discussed with a proposal of algorithm in the situation.

The initial management of trauma patients is an especially relevant setting to evaluate professional practice patterns

The initial management of trauma patients in a dedicated location is a crucial step in the treatment of these patients. The characteristics of this phase are such that they meet all the criteria for a professional practice patterns evaluation (PPPE or PPE): formalized protocols, clear-cut timeframes, specific roles of different stakeholders, and multidisciplinary medical and paramedical team. In addition, the expected result of the PPE approach, improved care, will have a direct impact on patient outcomes. This PPE modeled on an audit aims at evaluating the care process based on representative criteria. These criteria should include: the planned structure and organization; the protocols; the strategy and time frames for procedure implementation; the relationships between stakeholders; the results. For each criterion, differences between the expected characteristics and the observed reality are analyzed. The prospective (independent observer or video) and/or retrospective (records, register) collection of data during 20 consecutive encounters should be sufficient to identify dysfunctions and provide guidance on the changes that need to be implemented. The proposed data collection form includes 15 items representative of the five defined criteria. These items often describe departmental choice. The pursuit of quality is defined first in terms of medical and paramedical results, but also in administrative and financial terms. Following the analysis produced by a representative group of actors, a multidisciplinary discussion of the results should be followed by proposals for simple changes approved by everyone. After a few months of implementation, the impact of the proposed improvement measures will be assessed by a new survey. This approach, in addition to improving the quality of care, allows better team stress management and greater work enjoyment.

[Reliability of the pulse contour analysis for cardiac output measurement for assessing the fluid responsiveness]

BACKGROUND

The cardiac output (CO) is classically measured in intensive care unit patients. pulse contour (PC) method allows monitoring of CO.

OBJECTIVE

The aim of the present study was to assess the ability of PC to assess the fluid responsiveness defined as an increase in CO more than or equal to 15% after 500 mL hydroxyethyl starch over 20 minutes.

PATIENTS AND METHODS

In this observational prospective study, patients in shock in whom a PC method was inserted were included. CO was measure using the PC and thermodilution methods before and after a fluid challenge indicated by the physician. The correlation coefficient was measured, the diagram of Bland and Altman was built and the percentage of error (Critchley and Critchley method) was calculated. The ability of PC to diagnose fluid responsiveness was assessed using a receiver operating characteristics (ROC) curve.

RESULTS

Sixty-two fluid challenges were performed in 37 included patients. After fluid challenge, r(2) was 0.05 (P<0.01), the bias between PC and thermodilution was 0.3 ± 1.2L/min and the percentage of error was 36%. The area of the ROC curve was 0.601 [0.468-0.723].

CONCLUSION

In ICU patients with shock, PC cannot replace thermodilution to diagnose fluid responsiveness.

[Aortic thrombi associated with thoracic gunshot wound]

We report the case of a stroke due to a ballistic thoracic traumatism. The vascular injury, provoked by the passage of the bullet, associated to a procoagulating state led to the formation of a thrombus in the ascending aorta. The migration of this thrombus caused a stroke, finally reversible upon medical treatment only.

Airway management in trauma

Maintenance of a patent and prevention of aspiration are essential for the management of the trauma patient, that requires experienced physicians in airway control techniques. Difficulties of the airway control in the trauma setting are increased by the vital failures, the risk of aspiration, the potential cervical spine injury, the combative patient, and the obvious risk of difficult tracheal intubation related to specific injury related to the trauma. Endotracheal intubation remains the gold standard in trauma patient airway management and should be performed via the oral route with a rapid sequence induction and a manual in-line stabilization maneuver, to decrease the risks previously mentioned. Different techniques to control the airway in trauma patients are presented: improvement of the laryngoscopic vision, lighted stylet tracheal intubation, retrograde technique for orotracheal intubation, the laryngeal mask and the intubating laryngeal mask airways, the combitube and cricothyroidotomy. Management of the airway in trauma patients requires regular training in these techniques and the knowledge of complementary techniques allowing tracheal intubation or oxygenation to overcome difficult intubation and to prevent major complications as hypoxemia and aspiration.

An evaluation of capnography monitoring during the apnoea test in brain-dead patients

BACKGROUND AND OBJECTIVE

Diagnosis of brain death usually requires the absence of spontaneous respiratory movements during the apnoea test and an arterial carbon dioxide partial pressure above 60 mmHg. On the other hand, although capnography (end-tidal CO(2)) is currently monitored in intensive care unit patients, it has not been evaluated during the apnoea test in brain-dead patients. Therefore, the aim of this prospective study was first to investigate the usefulness of capnography monitoring, and secondly to evaluate the variation of the carbon dioxide partial pressure-end-tidal CO(2) gradient during the apnoea test in clinically brain-dead patients.

METHODS

After local Ethics Committee approval, 60 clinically brain-dead patients were investigated. End-tidal CO(2) was continuously recorded before, during and after the apnoea test. Arterial blood gases were sampled immediately before and after the apnoea test for calculation of the carbon dioxide partial pressure-end-tidal CO(2) gradient.

RESULTS

The apnoea test was clinically positive in 58 patients, whereas end-tidal CO(2) was equal to 0 during the apnoea. During the 20-min apnoea test, carbon dioxide partial pressure increased from 40 +/- 7 to 97 +/- 19 mmHg (P < 0.001) with a rate of 2.8 +/- 0.9 mmHg min(-1), end-tidal CO(2) increased from 31 +/- 6 to 68 +/- 17 mmHg (P < 0.001) and carbon dioxide partial pressure-end-tidal CO(2) gradient increased from 9 +/- 4 to 29 +/- 10 mmHg (P < 0.001). In two patients, the apnoea test was clinically negative because of the occurrence of spontaneous respiratory movements, whereas capnography showed contemporaneously significant increases in end-tidal CO(2).

CONCLUSIONS

End-tidal CO(2) should be systematically monitored and recorded, at least for medico-legal considerations, during the apnoea test in brain-dead patients. The high variability in the carbon dioxide partial pressure-end-tidal CO(2) gradient increase precludes any extrapolation of the carbon dioxide partial pressure from the end-tidal CO(2) at the end of the apnoea test.

Les polytraumatismes sont plus graves après chute d’une grande hauteur qu’après accident de la voie publique

AIMS

To compare specific features and prognosis of polytrauma victims requiring urgent laparotomy, after a free fall from a height (FFH) or a motor vehicle accident (MVA).

PATIENTS AND METHODS

Urgent laparotomy was performed only in case of massive hemoperitoneum associated with hemodynamic instability. Injury severity score (ISS) and hospital mortality rate were used to determine the severity of trauma.

RESULTS

Two hundred and four patients underwent urgent laparotomy for blunt abdominal trauma: 79 after FFH (intentional defenestration: 65, accident: 14), and 125 after a MVA. Mean ISS was higher after FFH (39 +/- 11) than MVA (35 +/- 12) (P< 0.05). Spine injury and pelvic fractures were more frequent and more severe in FFH patients, with a high incidence of retroperitoneal hemorrhage. Juxta-hepatic veins and inferior vena cava tears usually occurred after FFH. Hospital mortality was 48% (38/79) after FFH and 30% (37/125) after MVA (P< 0.01). Predominant cause of death was associated injuries. The height of the fall was not a prognostic factor, unlike the quality of the landing surface: the mortality dropped from 59% (34/58) when patient fell onto a hard ground, to 19% (4/21) in case of soft landing surface (P< 0.05).

CONCLUSION

Blunt abdominal trauma requiring urgent laparotomy is more severe after FFH than after MVA. The usual cause of death is associated injuries in both groups. Quality of the landing surface is a discriminating factor for mortality after FFH.

What pain scales do nurses use in the postanaesthesia care unit?

BACKGROUND AND OBJECTIVE

The visual analogue scale (VAS) is considered as the gold standard method for postoperative pain assessment. Nevertheless, in some clinical situations, this method may not be reliable. We performed an observational study to assess the use of the VAS and other pain scales by nurses in the postanaesthesia care unit.

METHODS

We studied the reasons for not using the VAS and asked if it may be less appropriate in certain age groups.

RESULTS

Among 600 patients included in the study (16% = 70 yr), nurses used the VAS in 53%, the numerical rating scale in 30%, the verbal rating scale in 12% and the behavioural scale in 5%. In 43% of the assessments, nursed did not use the VAS; the most frequently cited reason was related to their preference for other methods. In 54% of the assessments, the reason for not using the VAS was related to the patients, mainly when they were in too much pain to use it (22%). When the patient was in too much pain, the numerical rating scale was chosen in 54% and the behavioural scale in 27%. There was no difference between young patients and elderly patients.

CONCLUSIONS

Although the VAS is the standard method to assess pain, the nurses preferred using the numerical rating scale, both spontaneously or when VAS assessment was not possible.

Effects of halogenated anaesthetics on diaphragmatic actin-myosin cross-bridge kinetics

BACKGROUND

The effects of halogenated anaesthetics on cross-bridge (CB) kinetics are unclear. As halogenated anaesthetics do not markedly modify the intracellular calcium transient in the diaphragm, we used an isolated rat diaphragm preparation to assess the effects of halothane and isoflurane on CB kinetics.

METHODS

The effects of halothane and isoflurane (1 and 2 minimum alveolar concentration (MAC)) on rat diaphragm muscle strips were studied in vitro (Krebs-Henseleit solution, 29 degrees C, oxygen 95%/carbon dioxide 5%) in tetanus mode (50 Hz). From the force-velocity curve and using A. F. Huxley's equations, we determined the main mechanical and energetic variables and calculated CB kinetics.

RESULTS

At 1 and 2 MAC, isoflurane and halothane induced no significant inotropic effects. Whatever the concentrations tested, halothane and isoflurane did not significantly modify the CB number, the elementary force per CB, the attachment and detachment constants, the duration of the CB cycle and mean CB velocity.

CONCLUSION

In the rat diaphragm at therapeutic concentrations, halogenated anaesthetics do not significantly modify CB mechanical and kinetic properties.

Adjunctive analgesia with intravenous propacetamol does not reduce morphine-related adverse effects

BACKGROUND

Propacetamol is widely used in the management of postoperative pain. It decreases morphine requirements but its effect on the incidence of morphine-related adverse effects remains unknown.

METHODS

Patients (550) were randomly assigned to receive propacetamol or a placebo over the first 24 h after operation in a blinded study. Intravenous morphine titration was performed, after which morphine was administered s.c. every 4 h according to their pain score. Pain was assessed using a visual analogue scale (VAS). The primary end-point was the incidence of morphine-related adverse effects. The main secondary end-points were morphine requirements and VAS score.

RESULTS

After morphine titration, the VAS score and the number of patients with pain relief did not differ between groups. Morphine requirements were decreased in the propacetamol group (21 vs 14.5 mg, P<0.001) but the incidence of morphine-related adverse effects did not differ between groups (42 vs 46%, not significant). In patients with moderate pain (n=395), morphine requirements decreased by 37% (P<0.001) and the percentage of patients requiring no morphine was greater (21 vs 8%, P=0.002) in the propacetamol group. In patients with severe pain (n=155), morphine requirements decreased by 18% (P=0.04) in the propacetamol group and the number of patients who did not require morphine (3 vs 8%) did not differ significantly.

CONCLUSIONS

Although propacetamol induced a small morphine-sparing effect, it did not change the incidence of morphine-related adverse effects in the postoperative period. Moreover, no benefit could be demonstrated in patients with severe postoperative pain.

Is morphine-induced sedation synonymous with analgesia during intravenous morphine titration?

BACKGROUND

Postoperative morphine titration frequently induces sedation. The assumption is made that patients sleep when their pain is relieved. Some patients complain of persistent pain when they awake. We studied the time-course of sedation and analgesia to understand the determinants of patients' sleep during morphine titration.

METHODS

Seventy-three patients requiring morphine titration in a post-anaesthetic care unit after major surgery, were studied. Fifty-two patients slept (Sleep group) and 21 did not (Awake group). When a patient slept during titration, morphine was discontinued. Visual analogue pain scale (VAS), Ramsay score (RS), and the bispectral index (BIS) were recorded at the beginning of titration (STonset), at sleep onset (STsleep), then 5, 10, 20, and 30 min afterwards (ST4).

RESULTS

In the Sleep group, mean (SD) RS increased from 1.7 (0.4) to 2.4 (0.6) (P<0.05 vs STonset) and BIS decreased from 95 (5.0) to 89.8 (10.2) between STonset and STsleep (P<0.05), RS remained stable thereafter. Conversely, RS and BIS remained unaltered in the Awake group. The reduction in VAS was comparable between groups (from 78 (17) to 39 (21), and from 64 (16) to 30.4 (11), respectively). Even though mean (SD) VAS was 39 (21) at ST4 in the Sleep group, 13 patients (25%) maintained a VAS above 50 mm.

CONCLUSION

We observed dissociated effects of morphine on the time-course of sedation and analgesia with sedation occurring first, followed by analgesia. Therefore, morphine-induced sedation should not be considered as an indicator of an appropriate correct level of analgesia during i.v. morphine titration.

Effects of halothane and isoflurane on the contraction, relaxation and energetics of rat diaphragmatic muscle

BACKGROUND

The inotropic effects of halogenated anaesthetics on diaphragmatic muscle remain a matter of debate. Their effects on its relaxation are poorly understood, although diaphragmatic relaxation is recognized as an important physiological process that may interfere with diaphragmatic performance, fatigue and arterial blood flow.

METHODS

The effects of halothane and isoflurane (1 or 2 x minimum alveolar concentration [1 or 2 MAC]) on contraction and relaxation of rat diaphragm muscle strips (n = 40) were studied in vitro from force-velocity curves obtained at various loads from isotonic to isometric conditions. From these curves we determined the peak power output and the curvature. Data are mean (SD) percentage of baseline values.

RESULTS

At I MAC, isoflurane and halothane induced no significant inotropic and lusitropic effects. At 2 MAC, isoflurane induced a negative inotropic effect (active force, 93(5)% of baseline). Halothane and isoflurane induced a significant decrease in the peak power output at 2 MAC (88(8) and 86(9)% of baseline; P < 0.05), without significant changes in the curvature of the force-velocity curve. At 2 MAC isoflurane under high loads and halothane under low loads induced moderate negative lusitropic effects.

CONCLUSION

Halothane and isoflurane induced very moderate inotropic and lusitropic effects, suggesting that the decrease in diaphragm function observed in vivo is not related to a direct effect on diaphragmatic contractility.

Initial imaging assessment of severe blunt trauma

OBJECTIVES

Total body computed tomography (CT) scan is increasingly used in traumatised patients, but the need for an initial rapid imaging assessment beforehand remains unknown. To address this problem, we assessed the value of an initial imaging assessment (chest X-ray, pelvic X-ray, abdominal ultrasonography) in severely traumatised patients in a prospective study.

DESIGN AND SETTING

Prospective study of a cohort in a level 1 trauma centre of an university teaching hospital.

PATIENTS AND INTERVENTIONS

400 patients with severe blunt trauma. Within 30 min of arrival in the hospital, these patients underwent a rapid imaging assessment at the bedside, including chest and pelvic X-ray, and an abdominal ultrasonography. The decision taken for each imaging technique (chest drainage or thoracotomy, pelvic angiography, and laparotomy, respectively) was judged as appropriate or inappropriate.

MEASUREMENTS AND RESULTS

Emergency chest drainage or thoracotomy was performed in 78 cases (78 appropriate), pelvic angiography in 8 cases (5 appropriate) and immediate laparotomy in 48 cases (47 appropriate). Emergency treatment was decided in 108 patients, and the decisions were considered appropriate in 392 (98%, 95% CI: 97%-99%) cases. Three variables (heart rate, systolic arterial pressure and Glasgow Coma Scale) were independent predictors of the need for an emergency decision, but among patients who had none of these criteria, 16% required an emergency decision.

CONCLUSIONS

A simple and rapid initial imaging assessment enabled appropriate emergency decisions before further imaging assessment was performed. We recommend that every patient with severe blunt trauma receive this initial assessment.

Myocardial and coronary effects of propofol in rabbits with compensated cardiac hypertrophy

BACKGROUND

Myocardial effects of propofol have been previously investigated but most studies have been performed in healthy hearts. This study compared the cardiac effects of propofol on isolated normal and hypertrophic rabbits hearts.

METHODS

The effects of propofol (10-1,000 microM) on myocardial contractility, relaxation, coronary flow and oxygen consumption were investigated in hearts from rabbits with pressure overload-induced left ventricular hypertrophy (LVH group, n = 20) after aortic abdominal banding and from sham-operated control rabbits (SHAM group, n = 10), using an isolated and erythrocyte-perfused heart model. In addition, to assess the myocardial and coronary effects of propofol in more severe LVH, hearts with a degree of hypertrophy greater than 140% were selected (severe LVH group, n = 7).

RESULTS

The cardiac hypertrophy model induced significant left ventricular hypertrophy (136+/-21%, P < 0.05). The pressure-volume relation showed normal systolic function but an altered diastolic compliance in hypertrophic hearts. Propofol only decreased myocardial contractility and relaxation at supratherapeutic concentrations (> or = 300 microM) in SHAM and LVH groups. The decrease in myocardial performances was not significantly different in SHAM and LVH groups. Propofol induced a significant increase in coronary blood flow which was not significantly different between groups. In severe LVH group, the degree of hypertrophy reached to 157+/-23%. Similarly, the effects of concentrations of propofol were not significantly different from the SHAM group.

CONCLUSIONS

Propofol only decreased myocardial function at supratherapeutic concentrations. The myocardial and coronary effects of propofol were not significantly modified in cardiac hypertrophy.

Minimum alveolar concentration of volatile anesthetics in rats during postnatal maturation

BACKGROUND

Although neonatal rats have become widely used as experimental laboratory animals, minimum alveolar concentration (MAC) values of volatile anesthetics in rats during postnatal maturation remain unknown.

METHODS

We determined MAC values of volatile anesthetics in spontaneously breathing neonatal (2-, 9-, and 30-day-old) and adult Wistar rats exposed to increasing (in 0.1-0.2% steps) concentrations of halothane, isoflurane, or sevoflurane (n = 12-20 in each group), using the tail-clamp technique. MAC and its 95% confidence intervals were calculated using logistic regression and corrected for body temperature (37 degrees C).

RESULTS

In adult rats, inspired MAC values corrected at 37 degrees C were as follows: halothane, 0.88% (confidence interval, 0.82-0.93%); isoflurane, 1.12% (1.07-1.18%); and sevoflurane, 1.97% (1.84-2.10%). In 30-day-old rats, the values were as follows: halothane, 1.14% (1.07-1.20%); isoflurane, 1.67% (1.58-1.76%); and sevoflurane, 2.95% (2.75-3.15%). In 9-day-old rats, inspired MAC values were as follows: halothane, 1.68% (1.58-1.78%); isoflurane, 2.34% (2.21-2.47%); and sevoflurane, 3.74% (3.64-3.86%). In 2-day-old rats, inspired MAC values were as follows: halothane, 1.54% (1.44-1.64%); isoflurane, 1.86% (1.72-2.01%); and sevoflurane, 3.28% (3.09-3.47%).

CONCLUSION

As postnatal age increases, MAC value significantly increases, reaching the greatest value in 9-day-old rats, and decreases thereafter, and at 30 days is still greater than the adult MAC value.

Comparison of the intubating laryngeal mask airway with the fiberoptic intubation in anticipated difficult airway management

BACKGROUND

The intubating laryngeal mask airway (ILMA; Fastrach; Laryngeal Mask Company, Henley-on-Thames, UK) may provide an alternative technique to fiberoptic intubation (FIB) to facilitate the management of the anticipated difficult airway. The authors therefore compared the effectiveness of the ILMA with FIB in patients with anticipated difficult intubation.

METHODS

One hundred patients, with at least one difficult intubation criteria (Mallampati class III or IV, thyromental distance < 65 mm, interincisor distance < 35 mm) were enrolled (FIB group, n = 49; ILMA group, n = 51) in this prospective randomized study. Anesthesia was induced with propofol and maintained with alfentanil and propofol after an efficient mask ventilation has been demonstrated. The success of the technique (within three attempts), the number of attempts, duration of the successful attempt, and adverse events (oxygen saturation < 90%, bleeding) were recorded.

RESULTS

The rate of successful tracheal intubation with ILMA was 94% and comparable with FIB (92%). The number of attempts and the time to succeed were not significantly different between groups. In case of failure of the first technique, the alternative technique always succeeded. Failures in FIB group were related to oxygen desaturation (oxygen saturation < 90%) and bleeding, and to previous cervical radiotherapy in the ILMA group. Adverse events occurred significantly more frequently in FIB group than in ILMA group (18 vs. 0%, P < 0.05).

CONCLUSION

The authors obtained a high success rate and comparable duration of tracheal intubation with ILMA and FIB techniques. In patients with previous cervical radiotherapy, the use of ILMA cannot be recommended. Nevertheless, the use of the ILMA was associated with fewer adverse events.

Voluven, a lower substituted novel hydroxyethyl starch (HES 130/0.4), causes fewer effects on coagulation in major orthopedic surgery than HES 200/0.5

Hydroxyethyl starch (HES) solutions are effective plasma volume expanders. Impairment of coagulation occurs with large HES volumes infused perioperatively. Therefore, a lower substituted novel HES (Voluven; Fresenius Kabi, Bad Homburg, Germany) was developed to minimize hemostatic interactions, and was compared with HAES-steril (Fresenius Kabi) (pentastarch) regarding safety and efficacy. We performed a prospective, randomized, double-blinded study in 100 major orthopedic surgery patients. Because the 95% confidence interval (-330 mL; +284 mL) for the treatment contrast Voluven-HAES-steril was entirely included in the predefined equivalence range (+/- 500 mL), comparable efficacy was established. Voluven interfered significantly less than HAES-steril with coagulation factor VIII levels and partial thromboplastin time postoperatively. Total amounts of red blood cells transfused were comparable between the Voluven and HAES-steril groups, but a significantly reduced need for homologous red blood cells was observed in the Voluven group. We conclude that in large-blood-loss surgery, Voluven has a comparable efficacy with HAES-steril and may reduce coagulation impairment, possibly leading to a smaller number of allogeneic blood transfusions.

IMPLICATIONS

Hydroxyethyl starches are common plasma volume expanders, but may interfere with coagulation at large doses. We tested a novel hydroxyethyl starch specification (Voluven; Fresenius Kabi, Bad Homburg, Germany) which was developed to reduce hemostatic interactions while preserving its efficacy in restoring plasma volume in comparison to HAES-steril (pentastarch; Fresenius Kabi) in major orthopedic surgery.

Postoperative titration of intravenous morphine

BACKGROUND AND OBJECTIVE

Intravenous morphine titration is used to obtain postoperative pain relief, but few studies have assessed the appropriate regimen. In a quality programme, we performed a prospective non-randomized study of morphine titration in a postanaesthesia care unit (PACU).

METHODS

Four regimens of morphine titration were studied: every 10 (group 1, n = 400) or 5 min (group 2, n = 400) with a maximum of five intravenous boluses; every 5 min, without any limitation in the number of boluses (groups 3 and 4, n = 400 each); in groups 1, 2, and 3, subcutaneous morphine was administered 4 h after titration. In group 4, administration of subcutaneous morphine was allowed only 2 h after titration. A visual analogue pain scale (VAPS) > 30 mm was required to administer morphine and pain relief was defined as a VAPS < or = 30 mm.

RESULTS

After morphine titration, VAPS was lower and the number of patients with pain relief was greater in patients from groups 3 and 4. Patients from group 4 had the lowest VAPS (26 +/- 17 mm) and the highest percentage of pain relief (73%) at the end of the PACU period. The number of sedated patients increased in groups 3 (62%) and 4 (61%) compared with group 1 (27%). No significant differences in morphine-related adverse effects were observed.

CONCLUSION

Intravenous morphine titration every 5 min with an unlimited number of boluses and early subcutaneous administration provided the best analgesic regimen.

Effects of Dantrolene on Rat Diaphragm Muscle during Postnatal Maturation

Background

Dantrolene is the only known effective treatment for malignant hyperthermia. However, its effects on diaphragm muscle during postnatal maturation remain unknown.

Methods

The effects of dantrolene (10(-8) to 10(-4) M) were investigated in vitro on diaphragm muscle strips in adult rats and in postnatal rats aged 3, 10, and 17 days, and compared with those of ryanodine (10(-8) to 10(-6) M). The authors studied contraction and relaxation under isotonic and isometric conditions (29 degrees C, Krebs-Henseleit solution, tetanic stimulation at 50 Hz). Data are mean +/- SD.

Results

During postnatal maturation, the authors observed a progressive increase in active force developed per cross-sectional area (from 34 +/- 25 to 69 +/- 32 mN/mm2; P &lt; 0.05) and maximum shortening velocity (from 2.9 +/- 0.5 to 4.9 +/- 1.4 Lmax/s; P &lt; 0.05). Dantrolene induced a negative inotropic effect in diaphragm muscles in isotonic and isometric conditions in all groups, but this effect was significantly less marked in the 3-day-old rats compared with older rats. Dantrolene did not induce significant lusitropic effects during postnatal maturation. Developmental changes in the pharmacologic response to dantrolene were more rapid than those of ryanodine.

Conclusion

Dantrolene induced less pronounced negative inotropic effects on the diaphragm in neonatal rats as compared with adult rats. Our study suggests that developmental changes in the pharmacologic response to dantrolene are more rapid than those of ryanodine.

Randomised, placebo-controlled study of the postoperative analgesic effects of ketoprofen after spinal fusion surgery

BACKGROUND

The additive effect of non-steroidal anti-inflammatory drugs administered with propacetamol after major orthopaedic surgery has not been studied. Thus, we performed a prospective, placebo-controlled study to assess the analgesic effects of ketoprofen in patients undergoing spinal fusion surgery and receiving propacetamol.

METHODS

Fifty patients undergoing spinal fusion surgery received either 100 mg of ketoprofen every 8 h or a placebo, postoperatively. All patients received propacetamol and morphine (intravenous titration followed by patient-controlled analgesia (PCA) over 24 h). Pain was assessed using a visual analogue pain scale (VASpi). Data are mean+/-SD.

RESULTS

During morphine titration, ketoprofen did not significantly reduce the dose of morphine (8+/-6 vs 11+/-4 mg, NS) whereas it significantly decreased VASpi (P<0.001). During PCA, ketoprofen significantly reduced morphine consumption (25+/-17 vs 38+/-20 mg, P=0.04) and VASpi (P=0.002). The total postoperative morphine consumption was significantly (33%) reduced with ketoprofen.

CONCLUSION

Ketoprofen reduced morphine requirements and improved postoperative analgesia in patients undergoing major spinal surgery and receiving propacetamol.