Ketamine versus hydromorphone patient-controlled analgesia for acute pain in trauma patients.

BACKGROUND: It is unknown whether ketamine administered via patient-controlled analgesia (PCA) provides adequate analgesia while reducing opioid consumption in the traumatically injured patient. Differences in opioid consumption, pain scores, and adverse effects between ketamine and hydromorphone PCA were studied. MATERIALS AND METHODS: This is an investigator-initiated, single-center, double-blinded, randomized, pilot trial conducted from 2014 to 2016 at a level 1 trauma center. Nonintubated trauma patients in intensive care, who were receiving PCA, were randomized to ketamine or hydromorphone PCA plus opioid analgesics for breakthrough pain. RESULTS: Twenty subjects were randomized. There was no difference in median daily breakthrough opioid use (10 [0.63-19.38] mg versus 10 [4.38-22.5] mg, P = 0.55). Subjects in the ketamine group had lower median cumulative opioid use on therapy day 1 than the hydromorphone group (4.6 [2.5-15] mg versus 41.8 [31.8-50] mg, P < 0.001), as well as in the first 48 h (10 [3.3-15] mg versus 48.5 [32.1-67.5] mg, P < 0.001) and first 72 h (10 [4.2-15] mg versus 42.5 [31.7-65.2] mg, P < 0.001) of therapy. Daily oxygen supplementation requirements were lower in the ketamine group (0.5 [0-1.5] L/min versus 2 [0.5-3] L/min, P = 0.020). Hallucinations occurred more frequently in the ketamine group (40% versus 0%, P = 0.090). CONCLUSIONS: Ketamine PCA led to lower cumulative opioid consumption and lower oxygen supplementation requirements, though hallucinations occurred more frequently with use of ketamine. Additional studies are needed to investigate the tolerability of ketamine as an alternative to traditional opioid-based PCA.

Measuring Intangibles: Defining Predictors of Non-Technical Skills in Critical Care Air Transport Team Trainees.

BACKGROUND: Critical Care Air Transport Teams (CCATTs) are integral to the U.S. Air Force aeromedical evacuation paradigm. The current study was conducted to evaluate predictors of nontechnical skills (NOTECHS) in CCATT trainees. METHODS: Sixteen CCATTs were studied over a 6-month period. Team members completed a biographical survey and teams were videotaped during a simulated CCATT mission. Teams and individuals were assigned a "red flag score" using a validated assessment tool for NOTECHS. Salivary cortisol levels were measured at baseline and pre- and postsimulation exercises. RESULTS: 63% of participants reported regular intensive care unit (ICU) experience and 67% had flown real-world CCATT missions. Sixteen simulated missions were reviewed, with 69 crisis events identified. Task saturation was observed in 42% of crisis events. Average team red flag score correlated with task saturation during the simulated missions (odds ratio = 0.5). Daily ICU experience (p < 0.03) and previous deployment (p < 0.04) correlated with NOTECHS performance. Cortisol levels increased from baseline as the result of the simulation (p < 0.01) but did not correlate with red flag scores or biographical data. CONCLUSIONS: Task saturation occurred frequently and correlated with performance of NOTECHS. Previous real-world CCATT experience and daily ICU care correlated with improved performance of NOTECHS.

Oxygen requirement to reverse altitude-induced hypoxemia with continuous flow and pulsed dose oxygen.

BACKGROUND: Hypoxemia secondary to reduced barometric pressure is a complication of ascent to altitude. We designed a study to compare the reversal of hypobaric hypoxemia at 14,000 ft with continuous flow oxygen from a cylinder and pulsed dose oxygen from a portable concentrator. METHODS: There were 30 healthy volunteers who were randomized to one of three study groups, placed in an altitude chamber, and ascended to 14,000 ft. There were 10 subjects in each study group. Subjects breathed room air for 10 min to induce hypoxemia. Oxygen was then delivered via a nasal cannula from a cylinder at 1, 2, or 3 lpm of continuous flow for 10 min. The subjects again breathed room air at altitude for 10 min and were then placed on pulsed dose oxygen and titrated to obtain the continuous flow Spo2 equivalent. Spo2, Etco2, RR, HR, Hgb, and tissue oxygenation (Sto2) were continuously recorded. RESULTS: The 1-lpm group's Spo2 range was 89-99%. The 2-lpm group's Spo2 range was 95-98%, and the 3-lpm group's Spo2 range was 95-99%. The 2-lpm and 3-lpm flows were able to correct hypoxemia in every subject. The mean pulsed dose required to achieve an equivalent Spo2 ranged from 36.8 ml ± 18.9 ml in the 1-lpm arm, and 102.4 ml ± 53.8 in the 3-lpm arm. CONCLUSIONS: Portable oxygen concentrators using pulsed dose technology corrected hypoxemia in every subject. Oxygen concentrators may be an alternative to liquid oxygen or cylinders for use during aeromedical evacuation.

Accuracy of noninvasive hemoglobin monitoring in patients at risk for hemorrhage.

BACKGROUND: Monitoring for acute blood loss is critical in surgical patients, and delays in identifying hemorrhage can result in poor outcomes. The current standard of care for monitoring patients at risk for bleeding is serial measurement of hemoglobin (Hgb) by standard laboratory complete blood count (CBC). Point-of-care testing (i.e., iSTAT) can be a rapid method of evaluating Hgb, and spectrophotometry-based devices (i.e., Radical-7) offer the advantages of being continuous and noninvasive. We sought to evaluate the accuracy of Radical-7 and iSTAT in measuring Hgb and assessing for blood loss when compared with the criterion standard CBC. METHODS: Adult patients at risk for hemorrhage admitted to the surgical intensive care unit of a tertiary referral, Level I trauma center were eligible for this study. Serial CBC Hgb measurements were drawn as clinically indicated. The Radical-7 device was placed on the patient for noninvasive Hgb measurements (SpHb), and at each CBC measurement, concurrent iSTAT Hgb measurements were obtained. Bland-Altman analysis was used to compare the three methods of measuring Hgb with accuracy defined as measurements within 1.0-g/dL CBC Hgb. Concordance measurements were also performed to compare trends between values. RESULTS: Eighty-eight patients were enrolled and underwent 572 CBC measurements. Bland-Altman analysis of SpHb versus CBC resulted in an estimated bias of 1.49 g/dL, with 95% limits of agreement of -2.2 g/dL to 5.0 g/dL. iSTAT versus CBC resulted in an estimated bias of -0.63 g/dL, with 95% limits of agreement of -3.4 g/dL to 2.2 g/dL. Changes in SpHb had concordance with CBC Hgb 60% of the time, compared with 76% for iSTAT versus CBC CONCLUSION: Radical-7 SpHb was inaccurate when compared with CBC Hgb levels, and serial SpHb achieved concordance with CBC Hgb 60% of the time. As such, the clinical utility of Radical-7 as a rapid, noninvasive predictor of acute hemorrhage may be limited. LEVEL OF EVIDENCE: Diagnostic study, level II; care management, level III.

Major bile duct injury resulting from radiofrequency-assisted hepatectomy.

Radiofrequency parenchymal coagulation of the hepatic parenchyma prior to division is increasingly being used as an adjunct for reducing blood loss during the parenchymal transection phase of hepatectomy. However, recent reports have suggested that radiofrequency techniques result in an increased number of complications and liver damage compared to the clamp-crush technique. We believe this is a first report of a major hilar bile duct injury, a severe complication of RF-assisted hepatectomy, resulting from use of a monopolar device and discusses the merits of bipolar over monopolar RF electrode configuration when used to pre-coagulate liver tissue prior to transection. Our case underscores the need for judicious use of radiofrequency energy devices, particularly for liver resections that involve central transection planes.

Methods of advanced wound management for care of combined traumatic and chemical warfare injuries.

OBJECTIVE: Chemical warfare agents are potential threats to military personnel and civilians. The potential for associated traumatic injuries is significant. Damage control surgery could expose medical personnel to agents contaminating the wounds. The objectives of this study were to demonstrate efficacy of surgical decontamination and assess exposure risk to attending personnel. METHODS: Weanling pigs were randomly assigned to 2 of 4 debridement tools (scalpel, Bovie knife, Fugo Blade, and Versajet Hydrosurgery System). Penetrating traumatic wounds were created over the shoulder and thigh and then exposed to liquid sulfur mustard (HD) for 60 minutes. Excisional debridement of the injuries was performed while vapors over each site were collected. Gas chromatography was used to measure HD in samples of collected vapors. Unbound HD was quantified in presurgical wound swabs, excised tissues, and peripheral tissue biopsies following solvent extraction. RESULTS: Excisional debridement produced agent-free wound beds (surgical decontamination). A significant amount of HD vapor was detected above the surgical fields with each tool. Apart from the Versajet producing significantly lower levels of HD detected over thigh wounds compared with those treated using the scalpel, there were no differences in the amount of agent detected among the tools. All measured levels significantly exceeded established safety limits. Vesicating levels of unbound HD were extracted from excised tissue. There was no measured lateral spreading of HD beyond the surgical margins. CONCLUSIONS: There is significant occupational exposure risk to HD during surgical procedures designed to stabilize agent-contaminated wounds. If appropriate protective measures are taken, surgical decontamination is both effective and safe.